/usr/src/gnu/usr.bin/clang/libclangSema/../../../llvm/clang/lib/Sema/SemaCast.cpp

Bug Summary

File:	src/gnu/usr.bin/clang/libclangSema/../../../llvm/clang/lib/Sema/SemaCast.cpp
Warning:	line 1358, column 14 Called C++ object pointer is null

Annotated Source Code

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clang -cc1 -cc1 -triple amd64-unknown-openbsd7.0 -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name SemaCast.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -mrelocation-model static -mframe-pointer=all -relaxed-aliasing -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -fcoverage-compilation-dir=/usr/src/gnu/usr.bin/clang/libclangSema/obj -resource-dir /usr/local/lib/clang/13.0.0 -I /usr/src/gnu/usr.bin/clang/libclangSema/obj/../include/clang/Sema -I /usr/src/gnu/usr.bin/clang/libclangSema/../../../llvm/clang/include -I /usr/src/gnu/usr.bin/clang/libclangSema/../../../llvm/llvm/include -I /usr/src/gnu/usr.bin/clang/libclangSema/../include -I /usr/src/gnu/usr.bin/clang/libclangSema/obj -I /usr/src/gnu/usr.bin/clang/libclangSema/obj/../include -D NDEBUG -D __STDC_LIMIT_MACROS -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D LLVM_PREFIX="/usr" -internal-isystem /usr/include/c++/v1 -internal-isystem /usr/local/lib/clang/13.0.0/include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-comment -std=c++14 -fdeprecated-macro -fdebug-compilation-dir=/usr/src/gnu/usr.bin/clang/libclangSema/obj -ferror-limit 19 -fvisibility-inlines-hidden -fwrapv -stack-protector 2 -fno-rtti -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -fno-builtin-malloc -fno-builtin-calloc -fno-builtin-realloc -fno-builtin-valloc -fno-builtin-free -fno-builtin-strdup -fno-builtin-strndup -analyzer-output=html -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /home/ben/Projects/vmm/scan-build/2022-01-12-194120-40624-1 -x c++ /usr/src/gnu/usr.bin/clang/libclangSema/../../../llvm/clang/lib/Sema/SemaCast.cpp

/usr/src/gnu/usr.bin/clang/libclangSema/../../../llvm/clang/lib/Sema/SemaCast.cpp

→

1//===--- SemaCast.cpp - Semantic Analysis for Casts -----------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9//  This file implements semantic analysis for cast expressions, including
10//  1) C-style casts like '(int) x'
11//  2) C++ functional casts like 'int(x)'
12//  3) C++ named casts like 'static_cast<int>(x)'
13//
14//===----------------------------------------------------------------------===//

16#include "clang/AST/ASTContext.h"
17#include "clang/AST/ASTStructuralEquivalence.h"
18#include "clang/AST/CXXInheritance.h"
19#include "clang/AST/ExprCXX.h"
20#include "clang/AST/ExprObjC.h"
21#include "clang/AST/RecordLayout.h"
22#include "clang/Basic/PartialDiagnostic.h"
23#include "clang/Basic/TargetInfo.h"
24#include "clang/Lex/Preprocessor.h"
25#include "clang/Sema/Initialization.h"
26#include "clang/Sema/SemaInternal.h"
27#include "llvm/ADT/SmallVector.h"
28#include <set>
29using namespace clang;



33enum TryCastResult {
TC_NotApplicable, ///< The cast method is not applicable.
TC_Success,       ///< The cast method is appropriate and successful.
TC_Extension,     ///< The cast method is appropriate and accepted as a
                  ///< language extension.
TC_Failed         ///< The cast method is appropriate, but failed. A
                  ///< diagnostic has been emitted.
40};

42static bool isValidCast(TryCastResult TCR) {
return TCR == TC_Success || TCR == TC_Extension;
44}

46enum CastType {
CT_Const,       ///< const_cast
CT_Static,      ///< static_cast
CT_Reinterpret, ///< reinterpret_cast
CT_Dynamic,     ///< dynamic_cast
CT_CStyle,      ///< (Type)expr
CT_Functional,  ///< Type(expr)
CT_Addrspace    ///< addrspace_cast
54};

56namespace {
struct CastOperation {
  CastOperation(Sema &S, QualType destType, ExprResult src)
    : Self(S), SrcExpr(src), DestType(destType),
      ResultType(destType.getNonLValueExprType(S.Context)),
      ValueKind(Expr::getValueKindForType(destType)),
      Kind(CK_Dependent), IsARCUnbridgedCast(false) {

    // C++ [expr.type]/8.2.2:
    //   If a pr-value initially has the type cv-T, where T is a
    //   cv-unqualified non-class, non-array type, the type of the
    //   expression is adjusted to T prior to any further analysis.
    if (!S.Context.getLangOpts().ObjC && !DestType->isRecordType() &&
        !DestType->isArrayType()) {
      DestType = DestType.getUnqualifiedType();
    }

    if (const BuiltinType *placeholder =
          src.get()->getType()->getAsPlaceholderType()) {
      PlaceholderKind = placeholder->getKind();
    } else {
      PlaceholderKind = (BuiltinType::Kind) 0;
    }
  }

  Sema &Self;
  ExprResult SrcExpr;
  QualType DestType;
  QualType ResultType;
  ExprValueKind ValueKind;
  CastKind Kind;
  BuiltinType::Kind PlaceholderKind;
  CXXCastPath BasePath;
  bool IsARCUnbridgedCast;

  SourceRange OpRange;
  SourceRange DestRange;

  // Top-level semantics-checking routines.
  void CheckConstCast();
  void CheckReinterpretCast();
  void CheckStaticCast();
  void CheckDynamicCast();
  void CheckCXXCStyleCast(bool FunctionalCast, bool ListInitialization);
  void CheckCStyleCast();
  void CheckBuiltinBitCast();
  void CheckAddrspaceCast();

  void updatePartOfExplicitCastFlags(CastExpr *CE) {
    // Walk down from the CE to the OrigSrcExpr, and mark all immediate
    // ImplicitCastExpr's as being part of ExplicitCastExpr. The original CE
    // (which is a ExplicitCastExpr), and the OrigSrcExpr are not touched.
    for (; auto *ICE = dyn_cast<ImplicitCastExpr>(CE->getSubExpr()); CE = ICE)
      ICE->setIsPartOfExplicitCast(true);
  }

  /// Complete an apparently-successful cast operation that yields
  /// the given expression.
  ExprResult complete(CastExpr *castExpr) {
    // If this is an unbridged cast, wrap the result in an implicit
    // cast that yields the unbridged-cast placeholder type.
    if (IsARCUnbridgedCast) {
      castExpr = ImplicitCastExpr::Create(
          Self.Context, Self.Context.ARCUnbridgedCastTy, CK_Dependent,
          castExpr, nullptr, castExpr->getValueKind(),
          Self.CurFPFeatureOverrides());
    }
    updatePartOfExplicitCastFlags(castExpr);
    return castExpr;
  }

  // Internal convenience methods.

  /// Try to handle the given placeholder expression kind.  Return
  /// true if the source expression has the appropriate placeholder
  /// kind.  A placeholder can only be claimed once.
  bool claimPlaceholder(BuiltinType::Kind K) {
    if (PlaceholderKind != K) return false;

    PlaceholderKind = (BuiltinType::Kind) 0;
    return true;
  }

  bool isPlaceholder() const {
    return PlaceholderKind != 0;
  }
  bool isPlaceholder(BuiltinType::Kind K) const {
    return PlaceholderKind == K;
  }

  // Language specific cast restrictions for address spaces.
  void checkAddressSpaceCast(QualType SrcType, QualType DestType);

  void checkCastAlign() {
    Self.CheckCastAlign(SrcExpr.get(), DestType, OpRange);
  }

  void checkObjCConversion(Sema::CheckedConversionKind CCK) {
    assert(Self.getLangOpts().allowsNonTrivialObjCLifetimeQualifiers())((void)0);

    Expr *src = SrcExpr.get();
    if (Self.CheckObjCConversion(OpRange, DestType, src, CCK) ==
        Sema::ACR_unbridged)
      IsARCUnbridgedCast = true;
    SrcExpr = src;
  }

  /// Check for and handle non-overload placeholder expressions.
  void checkNonOverloadPlaceholders() {
    if (!isPlaceholder() || isPlaceholder(BuiltinType::Overload))
      return;

    SrcExpr = Self.CheckPlaceholderExpr(SrcExpr.get());
    if (SrcExpr.isInvalid())
      return;
    PlaceholderKind = (BuiltinType::Kind) 0;
  }
};

void CheckNoDeref(Sema &S, const QualType FromType, const QualType ToType,
                  SourceLocation OpLoc) {
  if (const auto *PtrType = dyn_cast<PointerType>(FromType)) {
    if (PtrType->getPointeeType()->hasAttr(attr::NoDeref)) {
      if (const auto *DestType = dyn_cast<PointerType>(ToType)) {
        if (!DestType->getPointeeType()->hasAttr(attr::NoDeref)) {
          S.Diag(OpLoc, diag::warn_noderef_to_dereferenceable_pointer);
        }
      }
    }
  }
}

struct CheckNoDerefRAII {
  CheckNoDerefRAII(CastOperation &Op) : Op(Op) {}
  ~CheckNoDerefRAII() {
    if (!Op.SrcExpr.isInvalid())
      CheckNoDeref(Op.Self, Op.SrcExpr.get()->getType(), Op.ResultType,
                   Op.OpRange.getBegin());
  }

  CastOperation &Op;
};
198}

200static void DiagnoseCastQual(Sema &Self, const ExprResult &SrcExpr,
                           QualType DestType);

203// The Try functions attempt a specific way of casting. If they succeed, they
204// return TC_Success. If their way of casting is not appropriate for the given
205// arguments, they return TC_NotApplicable and *may* set diag to a diagnostic
206// to emit if no other way succeeds. If their way of casting is appropriate but
207// fails, they return TC_Failed and *must* set diag; they can set it to 0 if
208// they emit a specialized diagnostic.
209// All diagnostics returned by these functions must expect the same three
210// arguments:
211// %0: Cast Type (a value from the CastType enumeration)
212// %1: Source Type
213// %2: Destination Type
214static TryCastResult TryLValueToRValueCast(Sema &Self, Expr *SrcExpr,
                                         QualType DestType, bool CStyle,
                                         CastKind &Kind,
                                         CXXCastPath &BasePath,
                                         unsigned &msg);
219static TryCastResult TryStaticReferenceDowncast(Sema &Self, Expr *SrcExpr,
                                             QualType DestType, bool CStyle,
                                             SourceRange OpRange,
                                             unsigned &msg,
                                             CastKind &Kind,
                                             CXXCastPath &BasePath);
225static TryCastResult TryStaticPointerDowncast(Sema &Self, QualType SrcType,
                                            QualType DestType, bool CStyle,
                                            SourceRange OpRange,
                                            unsigned &msg,
                                            CastKind &Kind,
                                            CXXCastPath &BasePath);
231static TryCastResult TryStaticDowncast(Sema &Self, CanQualType SrcType,
                                     CanQualType DestType, bool CStyle,
                                     SourceRange OpRange,
                                     QualType OrigSrcType,
                                     QualType OrigDestType, unsigned &msg,
                                     CastKind &Kind,
                                     CXXCastPath &BasePath);
238static TryCastResult TryStaticMemberPointerUpcast(Sema &Self, ExprResult &SrcExpr,
                                             QualType SrcType,
                                             QualType DestType,bool CStyle,
                                             SourceRange OpRange,
                                             unsigned &msg,
                                             CastKind &Kind,
                                             CXXCastPath &BasePath);

246static TryCastResult TryStaticImplicitCast(Sema &Self, ExprResult &SrcExpr,
                                         QualType DestType,
                                         Sema::CheckedConversionKind CCK,
                                         SourceRange OpRange,
                                         unsigned &msg, CastKind &Kind,
                                         bool ListInitialization);
252static TryCastResult TryStaticCast(Sema &Self, ExprResult &SrcExpr,
                                 QualType DestType,
                                 Sema::CheckedConversionKind CCK,
                                 SourceRange OpRange,
                                 unsigned &msg, CastKind &Kind,
                                 CXXCastPath &BasePath,
                                 bool ListInitialization);
259static TryCastResult TryConstCast(Sema &Self, ExprResult &SrcExpr,
                                QualType DestType, bool CStyle,
                                unsigned &msg);
262static TryCastResult TryReinterpretCast(Sema &Self, ExprResult &SrcExpr,
                                      QualType DestType, bool CStyle,
                                      SourceRange OpRange, unsigned &msg,
                                      CastKind &Kind);
266static TryCastResult TryAddressSpaceCast(Sema &Self, ExprResult &SrcExpr,
                                       QualType DestType, bool CStyle,
                                       unsigned &msg, CastKind &Kind);

270/// ActOnCXXNamedCast - Parse
271/// {dynamic,static,reinterpret,const,addrspace}_cast's.
272ExprResult
273Sema::ActOnCXXNamedCast(SourceLocation OpLoc, tok::TokenKind Kind,
                      SourceLocation LAngleBracketLoc, Declarator &D,
                      SourceLocation RAngleBracketLoc,
                      SourceLocation LParenLoc, Expr *E,
                      SourceLocation RParenLoc) {

assert(!D.isInvalidType())((void)0);

TypeSourceInfo *TInfo = GetTypeForDeclaratorCast(D, E->getType());
if (D.isInvalidType())
1
Taking false branch→
  return ExprError();

if (getLangOpts().CPlusPlus) {
2
←
Assuming field 'CPlusPlus' is 0→
3
←
Taking false branch→
  // Check that there are no default arguments (C++ only).
  CheckExtraCXXDefaultArguments(D);
}

return BuildCXXNamedCast(OpLoc, Kind, TInfo, E,
4
←
Calling 'Sema::BuildCXXNamedCast'→
                         SourceRange(LAngleBracketLoc, RAngleBracketLoc),
                         SourceRange(LParenLoc, RParenLoc));
293}

295ExprResult
296Sema::BuildCXXNamedCast(SourceLocation OpLoc, tok::TokenKind Kind,
                      TypeSourceInfo *DestTInfo, Expr *E,
                      SourceRange AngleBrackets, SourceRange Parens) {
ExprResult Ex = E;
QualType DestType = DestTInfo->getType();

// If the type is dependent, we won't do the semantic analysis now.
bool TypeDependent =
    DestType->isDependentType() || Ex.get()->isTypeDependent();
5
←
Assuming the condition is false→

CastOperation Op(*this, DestType, E);
Op.OpRange = SourceRange(OpLoc, Parens.getEnd());
Op.DestRange = AngleBrackets;

switch (Kind) {
6
←
Control jumps to 'case kw_static_cast:'  at line 366→
default: llvm_unreachable("Unknown C++ cast!")__builtin_unreachable();

case tok::kw_addrspace_cast:
  if (!TypeDependent) {
    Op.CheckAddrspaceCast();
    if (Op.SrcExpr.isInvalid())
      return ExprError();
  }
  return Op.complete(CXXAddrspaceCastExpr::Create(
      Context, Op.ResultType, Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
      DestTInfo, OpLoc, Parens.getEnd(), AngleBrackets));

case tok::kw_const_cast:
  if (!TypeDependent) {
    Op.CheckConstCast();
    if (Op.SrcExpr.isInvalid())
      return ExprError();
    DiscardMisalignedMemberAddress(DestType.getTypePtr(), E);
  }
  return Op.complete(CXXConstCastExpr::Create(Context, Op.ResultType,
                                Op.ValueKind, Op.SrcExpr.get(), DestTInfo,
                                              OpLoc, Parens.getEnd(),
                                              AngleBrackets));

case tok::kw_dynamic_cast: {
  // dynamic_cast is not supported in C++ for OpenCL.
  if (getLangOpts().OpenCLCPlusPlus) {
    return ExprError(Diag(OpLoc, diag::err_openclcxx_not_supported)
                     << "dynamic_cast");
  }

  if (!TypeDependent) {
    Op.CheckDynamicCast();
    if (Op.SrcExpr.isInvalid())
      return ExprError();
  }
  return Op.complete(CXXDynamicCastExpr::Create(Context, Op.ResultType,
                                  Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
                                                &Op.BasePath, DestTInfo,
                                                OpLoc, Parens.getEnd(),
                                                AngleBrackets));
}
case tok::kw_reinterpret_cast: {
  if (!TypeDependent) {
    Op.CheckReinterpretCast();
    if (Op.SrcExpr.isInvalid())
      return ExprError();
    DiscardMisalignedMemberAddress(DestType.getTypePtr(), E);
  }
  return Op.complete(CXXReinterpretCastExpr::Create(Context, Op.ResultType,
                                  Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
                                                    nullptr, DestTInfo, OpLoc,
                                                    Parens.getEnd(),
                                                    AngleBrackets));
}
case tok::kw_static_cast: {
  if (!TypeDependent) {
7
←
Assuming 'TypeDependent' is false→
8
←
Taking true branch→
    Op.CheckStaticCast();
9
←
Calling 'CastOperation::CheckStaticCast'→
    if (Op.SrcExpr.isInvalid())
      return ExprError();
    DiscardMisalignedMemberAddress(DestType.getTypePtr(), E);
  }

  return Op.complete(CXXStaticCastExpr::Create(
      Context, Op.ResultType, Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
      &Op.BasePath, DestTInfo, CurFPFeatureOverrides(), OpLoc,
      Parens.getEnd(), AngleBrackets));
}
}
380}

382ExprResult Sema::ActOnBuiltinBitCastExpr(SourceLocation KWLoc, Declarator &D,
                                       ExprResult Operand,
                                       SourceLocation RParenLoc) {
assert(!D.isInvalidType())((void)0);

TypeSourceInfo *TInfo = GetTypeForDeclaratorCast(D, Operand.get()->getType());
if (D.isInvalidType())
  return ExprError();

return BuildBuiltinBitCastExpr(KWLoc, TInfo, Operand.get(), RParenLoc);
392}

394ExprResult Sema::BuildBuiltinBitCastExpr(SourceLocation KWLoc,
                                       TypeSourceInfo *TSI, Expr *Operand,
                                       SourceLocation RParenLoc) {
CastOperation Op(*this, TSI->getType(), Operand);
Op.OpRange = SourceRange(KWLoc, RParenLoc);
TypeLoc TL = TSI->getTypeLoc();
Op.DestRange = SourceRange(TL.getBeginLoc(), TL.getEndLoc());

if (!Operand->isTypeDependent() && !TSI->getType()->isDependentType()) {
  Op.CheckBuiltinBitCast();
  if (Op.SrcExpr.isInvalid())
    return ExprError();
}

BuiltinBitCastExpr *BCE =
    new (Context) BuiltinBitCastExpr(Op.ResultType, Op.ValueKind, Op.Kind,
                                     Op.SrcExpr.get(), TSI, KWLoc, RParenLoc);
return Op.complete(BCE);
412}

414/// Try to diagnose a failed overloaded cast.  Returns true if
415/// diagnostics were emitted.
416static bool tryDiagnoseOverloadedCast(Sema &S, CastType CT,
                                    SourceRange range, Expr *src,
                                    QualType destType,
                                    bool listInitialization) {
switch (CT) {
// These cast kinds don't consider user-defined conversions.
case CT_Const:
case CT_Reinterpret:
case CT_Dynamic:
case CT_Addrspace:
  return false;

// These do.
case CT_Static:
case CT_CStyle:
case CT_Functional:
  break;
}

QualType srcType = src->getType();
if (!destType->isRecordType() && !srcType->isRecordType())
  return false;

InitializedEntity entity = InitializedEntity::InitializeTemporary(destType);
InitializationKind initKind
  = (CT == CT_CStyle)? InitializationKind::CreateCStyleCast(range.getBegin(),
                                                    range, listInitialization)
  : (CT == CT_Functional)? InitializationKind::CreateFunctionalCast(range,
                                                           listInitialization)
  : InitializationKind::CreateCast(/*type range?*/ range);
InitializationSequence sequence(S, entity, initKind, src);

assert(sequence.Failed() && "initialization succeeded on second try?")((void)0);
switch (sequence.getFailureKind()) {
default: return false;

case InitializationSequence::FK_ConstructorOverloadFailed:
case InitializationSequence::FK_UserConversionOverloadFailed:
  break;
}

OverloadCandidateSet &candidates = sequence.getFailedCandidateSet();

unsigned msg = 0;
OverloadCandidateDisplayKind howManyCandidates = OCD_AllCandidates;

switch (sequence.getFailedOverloadResult()) {
case OR_Success: llvm_unreachable("successful failed overload")__builtin_unreachable();
case OR_No_Viable_Function:
  if (candidates.empty())
    msg = diag::err_ovl_no_conversion_in_cast;
  else
    msg = diag::err_ovl_no_viable_conversion_in_cast;
  howManyCandidates = OCD_AllCandidates;
  break;

case OR_Ambiguous:
  msg = diag::err_ovl_ambiguous_conversion_in_cast;
  howManyCandidates = OCD_AmbiguousCandidates;
  break;

case OR_Deleted:
  msg = diag::err_ovl_deleted_conversion_in_cast;
  howManyCandidates = OCD_ViableCandidates;
  break;
}

candidates.NoteCandidates(
    PartialDiagnosticAt(range.getBegin(),
                        S.PDiag(msg) << CT << srcType << destType << range
                                     << src->getSourceRange()),
    S, howManyCandidates, src);

return true;
490}

492/// Diagnose a failed cast.
493static void diagnoseBadCast(Sema &S, unsigned msg, CastType castType,
                          SourceRange opRange, Expr *src, QualType destType,
                          bool listInitialization) {
if (msg == diag::err_bad_cxx_cast_generic &&
    tryDiagnoseOverloadedCast(S, castType, opRange, src, destType,
                              listInitialization))
  return;

S.Diag(opRange.getBegin(), msg) << castType
  << src->getType() << destType << opRange << src->getSourceRange();

// Detect if both types are (ptr to) class, and note any incompleteness.
int DifferentPtrness = 0;
QualType From = destType;
if (auto Ptr = From->getAs<PointerType>()) {
  From = Ptr->getPointeeType();
  DifferentPtrness++;
}
QualType To = src->getType();
if (auto Ptr = To->getAs<PointerType>()) {
  To = Ptr->getPointeeType();
  DifferentPtrness--;
}
if (!DifferentPtrness) {
  auto RecFrom = From->getAs<RecordType>();
  auto RecTo = To->getAs<RecordType>();
  if (RecFrom && RecTo) {
    auto DeclFrom = RecFrom->getAsCXXRecordDecl();
    if (!DeclFrom->isCompleteDefinition())
      S.Diag(DeclFrom->getLocation(), diag::note_type_incomplete) << DeclFrom;
    auto DeclTo = RecTo->getAsCXXRecordDecl();
    if (!DeclTo->isCompleteDefinition())
      S.Diag(DeclTo->getLocation(), diag::note_type_incomplete) << DeclTo;
  }
}
528}

530namespace {
531/// The kind of unwrapping we did when determining whether a conversion casts
532/// away constness.
533enum CastAwayConstnessKind {
/// The conversion does not cast away constness.
CACK_None = 0,
/// We unwrapped similar types.
CACK_Similar = 1,
/// We unwrapped dissimilar types with similar representations (eg, a pointer
/// versus an Objective-C object pointer).
CACK_SimilarKind = 2,
/// We unwrapped representationally-unrelated types, such as a pointer versus
/// a pointer-to-member.
CACK_Incoherent = 3,
544};
545}

547/// Unwrap one level of types for CastsAwayConstness.
548///
549/// Like Sema::UnwrapSimilarTypes, this removes one level of indirection from
550/// both types, provided that they're both pointer-like or array-like. Unlike
551/// the Sema function, doesn't care if the unwrapped pieces are related.
552///
553/// This function may remove additional levels as necessary for correctness:
554/// the resulting T1 is unwrapped sufficiently that it is never an array type,
555/// so that its qualifiers can be directly compared to those of T2 (which will
556/// have the combined set of qualifiers from all indermediate levels of T2),
557/// as (effectively) required by [expr.const.cast]p7 replacing T1's qualifiers
558/// with those from T2.
559static CastAwayConstnessKind
560unwrapCastAwayConstnessLevel(ASTContext &Context, QualType &T1, QualType &T2) {
enum { None, Ptr, MemPtr, BlockPtr, Array };
auto Classify = [](QualType T) {
  if (T->isAnyPointerType()) return Ptr;
  if (T->isMemberPointerType()) return MemPtr;
  if (T->isBlockPointerType()) return BlockPtr;
  // We somewhat-arbitrarily don't look through VLA types here. This is at
  // least consistent with the behavior of UnwrapSimilarTypes.
  if (T->isConstantArrayType() || T->isIncompleteArrayType()) return Array;
  return None;
};

auto Unwrap = [&](QualType T) {
  if (auto *AT = Context.getAsArrayType(T))
    return AT->getElementType();
  return T->getPointeeType();
};

CastAwayConstnessKind Kind;

if (T2->isReferenceType()) {
  // Special case: if the destination type is a reference type, unwrap it as
  // the first level. (The source will have been an lvalue expression in this
  // case, so there is no corresponding "reference to" in T1 to remove.) This
  // simulates removing a "pointer to" from both sides.
  T2 = T2->getPointeeType();
  Kind = CastAwayConstnessKind::CACK_Similar;
} else if (Context.UnwrapSimilarTypes(T1, T2)) {
  Kind = CastAwayConstnessKind::CACK_Similar;
} else {
  // Try unwrapping mismatching levels.
  int T1Class = Classify(T1);
  if (T1Class == None)
    return CastAwayConstnessKind::CACK_None;

  int T2Class = Classify(T2);
  if (T2Class == None)
    return CastAwayConstnessKind::CACK_None;

  T1 = Unwrap(T1);
  T2 = Unwrap(T2);
  Kind = T1Class == T2Class ? CastAwayConstnessKind::CACK_SimilarKind
                            : CastAwayConstnessKind::CACK_Incoherent;
}

// We've unwrapped at least one level. If the resulting T1 is a (possibly
// multidimensional) array type, any qualifier on any matching layer of
// T2 is considered to correspond to T1. Decompose down to the element
// type of T1 so that we can compare properly.
while (true) {
  Context.UnwrapSimilarArrayTypes(T1, T2);

  if (Classify(T1) != Array)
    break;

  auto T2Class = Classify(T2);
  if (T2Class == None)
    break;

  if (T2Class != Array)
    Kind = CastAwayConstnessKind::CACK_Incoherent;
  else if (Kind != CastAwayConstnessKind::CACK_Incoherent)
    Kind = CastAwayConstnessKind::CACK_SimilarKind;

  T1 = Unwrap(T1);
  T2 = Unwrap(T2).withCVRQualifiers(T2.getCVRQualifiers());
}

return Kind;
629}

631/// Check if the pointer conversion from SrcType to DestType casts away
632/// constness as defined in C++ [expr.const.cast]. This is used by the cast
633/// checkers. Both arguments must denote pointer (possibly to member) types.
634///
635/// \param CheckCVR Whether to check for const/volatile/restrict qualifiers.
636/// \param CheckObjCLifetime Whether to check Objective-C lifetime qualifiers.
637static CastAwayConstnessKind
638CastsAwayConstness(Sema &Self, QualType SrcType, QualType DestType,
                 bool CheckCVR, bool CheckObjCLifetime,
                 QualType *TheOffendingSrcType = nullptr,
                 QualType *TheOffendingDestType = nullptr,
                 Qualifiers *CastAwayQualifiers = nullptr) {
// If the only checking we care about is for Objective-C lifetime qualifiers,
// and we're not in ObjC mode, there's nothing to check.
if (!CheckCVR && CheckObjCLifetime && !Self.Context.getLangOpts().ObjC)
  return CastAwayConstnessKind::CACK_None;

if (!DestType->isReferenceType()) {
  assert((SrcType->isAnyPointerType() || SrcType->isMemberPointerType() ||((void)0)
          SrcType->isBlockPointerType()) &&((void)0)
         "Source type is not pointer or pointer to member.")((void)0);
  assert((DestType->isAnyPointerType() || DestType->isMemberPointerType() ||((void)0)
          DestType->isBlockPointerType()) &&((void)0)
         "Destination type is not pointer or pointer to member.")((void)0);
}

QualType UnwrappedSrcType = Self.Context.getCanonicalType(SrcType),
         UnwrappedDestType = Self.Context.getCanonicalType(DestType);

// Find the qualifiers. We only care about cvr-qualifiers for the
// purpose of this check, because other qualifiers (address spaces,
// Objective-C GC, etc.) are part of the type's identity.
QualType PrevUnwrappedSrcType = UnwrappedSrcType;
QualType PrevUnwrappedDestType = UnwrappedDestType;
auto WorstKind = CastAwayConstnessKind::CACK_Similar;
bool AllConstSoFar = true;
while (auto Kind = unwrapCastAwayConstnessLevel(
           Self.Context, UnwrappedSrcType, UnwrappedDestType)) {
  // Track the worst kind of unwrap we needed to do before we found a
  // problem.
  if (Kind > WorstKind)
    WorstKind = Kind;

  // Determine the relevant qualifiers at this level.
  Qualifiers SrcQuals, DestQuals;
  Self.Context.getUnqualifiedArrayType(UnwrappedSrcType, SrcQuals);
  Self.Context.getUnqualifiedArrayType(UnwrappedDestType, DestQuals);

  // We do not meaningfully track object const-ness of Objective-C object
  // types. Remove const from the source type if either the source or
  // the destination is an Objective-C object type.
  if (UnwrappedSrcType->isObjCObjectType() ||
      UnwrappedDestType->isObjCObjectType())
    SrcQuals.removeConst();

  if (CheckCVR) {
    Qualifiers SrcCvrQuals =
        Qualifiers::fromCVRMask(SrcQuals.getCVRQualifiers());
    Qualifiers DestCvrQuals =
        Qualifiers::fromCVRMask(DestQuals.getCVRQualifiers());

    if (SrcCvrQuals != DestCvrQuals) {
      if (CastAwayQualifiers)
        *CastAwayQualifiers = SrcCvrQuals - DestCvrQuals;

      // If we removed a cvr-qualifier, this is casting away 'constness'.
      if (!DestCvrQuals.compatiblyIncludes(SrcCvrQuals)) {
        if (TheOffendingSrcType)
          *TheOffendingSrcType = PrevUnwrappedSrcType;
        if (TheOffendingDestType)
          *TheOffendingDestType = PrevUnwrappedDestType;
        return WorstKind;
      }

      // If any prior level was not 'const', this is also casting away
      // 'constness'. We noted the outermost type missing a 'const' already.
      if (!AllConstSoFar)
        return WorstKind;
    }
  }

  if (CheckObjCLifetime &&
      !DestQuals.compatiblyIncludesObjCLifetime(SrcQuals))
    return WorstKind;

  // If we found our first non-const-qualified type, this may be the place
  // where things start to go wrong.
  if (AllConstSoFar && !DestQuals.hasConst()) {
    AllConstSoFar = false;
    if (TheOffendingSrcType)
      *TheOffendingSrcType = PrevUnwrappedSrcType;
    if (TheOffendingDestType)
      *TheOffendingDestType = PrevUnwrappedDestType;
  }

  PrevUnwrappedSrcType = UnwrappedSrcType;
  PrevUnwrappedDestType = UnwrappedDestType;
}

return CastAwayConstnessKind::CACK_None;
731}

733static TryCastResult getCastAwayConstnessCastKind(CastAwayConstnessKind CACK,
                                                unsigned &DiagID) {
switch (CACK) {
case CastAwayConstnessKind::CACK_None:
  llvm_unreachable("did not cast away constness")__builtin_unreachable();

case CastAwayConstnessKind::CACK_Similar:
  // FIXME: Accept these as an extension too?
case CastAwayConstnessKind::CACK_SimilarKind:
  DiagID = diag::err_bad_cxx_cast_qualifiers_away;
  return TC_Failed;

case CastAwayConstnessKind::CACK_Incoherent:
  DiagID = diag::ext_bad_cxx_cast_qualifiers_away_incoherent;
  return TC_Extension;
}

llvm_unreachable("unexpected cast away constness kind")__builtin_unreachable();
751}

753/// CheckDynamicCast - Check that a dynamic_cast\<DestType\>(SrcExpr) is valid.
754/// Refer to C++ 5.2.7 for details. Dynamic casts are used mostly for runtime-
755/// checked downcasts in class hierarchies.
756void CastOperation::CheckDynamicCast() {
CheckNoDerefRAII NoderefCheck(*this);

if (ValueKind == VK_PRValue)
  SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
else if (isPlaceholder())
  SrcExpr = Self.CheckPlaceholderExpr(SrcExpr.get());
if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
  return;

QualType OrigSrcType = SrcExpr.get()->getType();
QualType DestType = Self.Context.getCanonicalType(this->DestType);

// C++ 5.2.7p1: T shall be a pointer or reference to a complete class type,
//   or "pointer to cv void".

QualType DestPointee;
const PointerType *DestPointer = DestType->getAs<PointerType>();
const ReferenceType *DestReference = nullptr;
if (DestPointer) {
  DestPointee = DestPointer->getPointeeType();
} else if ((DestReference = DestType->getAs<ReferenceType>())) {
  DestPointee = DestReference->getPointeeType();
} else {
  Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_ref_or_ptr)
    << this->DestType << DestRange;
  SrcExpr = ExprError();
  return;
}

const RecordType *DestRecord = DestPointee->getAs<RecordType>();
if (DestPointee->isVoidType()) {
  assert(DestPointer && "Reference to void is not possible")((void)0);
} else if (DestRecord) {
  if (Self.RequireCompleteType(OpRange.getBegin(), DestPointee,
                               diag::err_bad_cast_incomplete,
                               DestRange)) {
    SrcExpr = ExprError();
    return;
  }
} else {
  Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_class)
    << DestPointee.getUnqualifiedType() << DestRange;
  SrcExpr = ExprError();
  return;
}

// C++0x 5.2.7p2: If T is a pointer type, v shall be an rvalue of a pointer to
//   complete class type, [...]. If T is an lvalue reference type, v shall be
//   an lvalue of a complete class type, [...]. If T is an rvalue reference
//   type, v shall be an expression having a complete class type, [...]
QualType SrcType = Self.Context.getCanonicalType(OrigSrcType);
QualType SrcPointee;
if (DestPointer) {
  if (const PointerType *SrcPointer = SrcType->getAs<PointerType>()) {
    SrcPointee = SrcPointer->getPointeeType();
  } else {
    Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_ptr)
        << OrigSrcType << this->DestType << SrcExpr.get()->getSourceRange();
    SrcExpr = ExprError();
    return;
  }
} else if (DestReference->isLValueReferenceType()) {
  if (!SrcExpr.get()->isLValue()) {
    Self.Diag(OpRange.getBegin(), diag::err_bad_cxx_cast_rvalue)
      << CT_Dynamic << OrigSrcType << this->DestType << OpRange;
  }
  SrcPointee = SrcType;
} else {
  // If we're dynamic_casting from a prvalue to an rvalue reference, we need
  // to materialize the prvalue before we bind the reference to it.
  if (SrcExpr.get()->isPRValue())
    SrcExpr = Self.CreateMaterializeTemporaryExpr(
        SrcType, SrcExpr.get(), /*IsLValueReference*/ false);
  SrcPointee = SrcType;
}

const RecordType *SrcRecord = SrcPointee->getAs<RecordType>();
if (SrcRecord) {
  if (Self.RequireCompleteType(OpRange.getBegin(), SrcPointee,
                               diag::err_bad_cast_incomplete,
                               SrcExpr.get())) {
    SrcExpr = ExprError();
    return;
  }
} else {
  Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_class)
    << SrcPointee.getUnqualifiedType() << SrcExpr.get()->getSourceRange();
  SrcExpr = ExprError();
  return;
}

assert((DestPointer || DestReference) &&((void)0)
  "Bad destination non-ptr/ref slipped through.")((void)0);
assert((DestRecord || DestPointee->isVoidType()) &&((void)0)
  "Bad destination pointee slipped through.")((void)0);
assert(SrcRecord && "Bad source pointee slipped through.")((void)0);

// C++ 5.2.7p1: The dynamic_cast operator shall not cast away constness.
if (!DestPointee.isAtLeastAsQualifiedAs(SrcPointee)) {
  Self.Diag(OpRange.getBegin(), diag::err_bad_cxx_cast_qualifiers_away)
    << CT_Dynamic << OrigSrcType << this->DestType << OpRange;
  SrcExpr = ExprError();
  return;
}

// C++ 5.2.7p3: If the type of v is the same as the required result type,
//   [except for cv].
if (DestRecord == SrcRecord) {
  Kind = CK_NoOp;
  return;
}

// C++ 5.2.7p5
// Upcasts are resolved statically.
if (DestRecord &&
    Self.IsDerivedFrom(OpRange.getBegin(), SrcPointee, DestPointee)) {
  if (Self.CheckDerivedToBaseConversion(SrcPointee, DestPointee,
                                         OpRange.getBegin(), OpRange,
                                         &BasePath)) {
    SrcExpr = ExprError();
    return;
  }

  Kind = CK_DerivedToBase;
  return;
}

// C++ 5.2.7p6: Otherwise, v shall be [polymorphic].
const RecordDecl *SrcDecl = SrcRecord->getDecl()->getDefinition();
assert(SrcDecl && "Definition missing")((void)0);
if (!cast<CXXRecordDecl>(SrcDecl)->isPolymorphic()) {
  Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_polymorphic)
    << SrcPointee.getUnqualifiedType() << SrcExpr.get()->getSourceRange();
  SrcExpr = ExprError();
}

// dynamic_cast is not available with -fno-rtti.
// As an exception, dynamic_cast to void* is available because it doesn't
// use RTTI.
if (!Self.getLangOpts().RTTI && !DestPointee->isVoidType()) {
  Self.Diag(OpRange.getBegin(), diag::err_no_dynamic_cast_with_fno_rtti);
  SrcExpr = ExprError();
  return;
}

// Warns when dynamic_cast is used with RTTI data disabled.
if (!Self.getLangOpts().RTTIData) {
  bool MicrosoftABI =
      Self.getASTContext().getTargetInfo().getCXXABI().isMicrosoft();
  bool isClangCL = Self.getDiagnostics().getDiagnosticOptions().getFormat() ==
                   DiagnosticOptions::MSVC;
  if (MicrosoftABI || !DestPointee->isVoidType())
    Self.Diag(OpRange.getBegin(),
              diag::warn_no_dynamic_cast_with_rtti_disabled)
        << isClangCL;
}

// Done. Everything else is run-time checks.
Kind = CK_Dynamic;
916}

918/// CheckConstCast - Check that a const_cast\<DestType\>(SrcExpr) is valid.
919/// Refer to C++ 5.2.11 for details. const_cast is typically used in code
920/// like this:
921/// const char *str = "literal";
922/// legacy_function(const_cast\<char*\>(str));
923void CastOperation::CheckConstCast() {
CheckNoDerefRAII NoderefCheck(*this);

if (ValueKind == VK_PRValue)
  SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
else if (isPlaceholder())
  SrcExpr = Self.CheckPlaceholderExpr(SrcExpr.get());
if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
  return;

unsigned msg = diag::err_bad_cxx_cast_generic;
auto TCR = TryConstCast(Self, SrcExpr, DestType, /*CStyle*/ false, msg);
if (TCR != TC_Success && msg != 0) {
  Self.Diag(OpRange.getBegin(), msg) << CT_Const
    << SrcExpr.get()->getType() << DestType << OpRange;
}
if (!isValidCast(TCR))
  SrcExpr = ExprError();
941}

943void CastOperation::CheckAddrspaceCast() {
unsigned msg = diag::err_bad_cxx_cast_generic;
auto TCR =
    TryAddressSpaceCast(Self, SrcExpr, DestType, /*CStyle*/ false, msg, Kind);
if (TCR != TC_Success && msg != 0) {
  Self.Diag(OpRange.getBegin(), msg)
      << CT_Addrspace << SrcExpr.get()->getType() << DestType << OpRange;
}
if (!isValidCast(TCR))
  SrcExpr = ExprError();
953}

955/// Check that a reinterpret_cast\<DestType\>(SrcExpr) is not used as upcast
956/// or downcast between respective pointers or references.
957static void DiagnoseReinterpretUpDownCast(Sema &Self, const Expr *SrcExpr,
                                        QualType DestType,
                                        SourceRange OpRange) {
QualType SrcType = SrcExpr->getType();
// When casting from pointer or reference, get pointee type; use original
// type otherwise.
const CXXRecordDecl *SrcPointeeRD = SrcType->getPointeeCXXRecordDecl();
const CXXRecordDecl *SrcRD =
  SrcPointeeRD ? SrcPointeeRD : SrcType->getAsCXXRecordDecl();

// Examining subobjects for records is only possible if the complete and
// valid definition is available.  Also, template instantiation is not
// allowed here.
if (!SrcRD || !SrcRD->isCompleteDefinition() || SrcRD->isInvalidDecl())
  return;

const CXXRecordDecl *DestRD = DestType->getPointeeCXXRecordDecl();

if (!DestRD || !DestRD->isCompleteDefinition() || DestRD->isInvalidDecl())
  return;

enum {
  ReinterpretUpcast,
  ReinterpretDowncast
} ReinterpretKind;

CXXBasePaths BasePaths;

if (SrcRD->isDerivedFrom(DestRD, BasePaths))
  ReinterpretKind = ReinterpretUpcast;
else if (DestRD->isDerivedFrom(SrcRD, BasePaths))
  ReinterpretKind = ReinterpretDowncast;
else
  return;

bool VirtualBase = true;
bool NonZeroOffset = false;
for (CXXBasePaths::const_paths_iterator I = BasePaths.begin(),
                                        E = BasePaths.end();
     I != E; ++I) {
  const CXXBasePath &Path = *I;
  CharUnits Offset = CharUnits::Zero();
  bool IsVirtual = false;
  for (CXXBasePath::const_iterator IElem = Path.begin(), EElem = Path.end();
       IElem != EElem; ++IElem) {
    IsVirtual = IElem->Base->isVirtual();
    if (IsVirtual)
      break;
    const CXXRecordDecl *BaseRD = IElem->Base->getType()->getAsCXXRecordDecl();
    assert(BaseRD && "Base type should be a valid unqualified class type")((void)0);
    // Don't check if any base has invalid declaration or has no definition
    // since it has no layout info.
    const CXXRecordDecl *Class = IElem->Class,
                        *ClassDefinition = Class->getDefinition();
    if (Class->isInvalidDecl() || !ClassDefinition ||
        !ClassDefinition->isCompleteDefinition())
      return;

    const ASTRecordLayout &DerivedLayout =
        Self.Context.getASTRecordLayout(Class);
    Offset += DerivedLayout.getBaseClassOffset(BaseRD);
  }
  if (!IsVirtual) {
    // Don't warn if any path is a non-virtually derived base at offset zero.
    if (Offset.isZero())
      return;
    // Offset makes sense only for non-virtual bases.
    else
      NonZeroOffset = true;
  }
  VirtualBase = VirtualBase && IsVirtual;
}

(void) NonZeroOffset; // Silence set but not used warning.
assert((VirtualBase || NonZeroOffset) &&((void)0)
       "Should have returned if has non-virtual base with zero offset")((void)0);

QualType BaseType =
    ReinterpretKind == ReinterpretUpcast? DestType : SrcType;
QualType DerivedType =
    ReinterpretKind == ReinterpretUpcast? SrcType : DestType;

SourceLocation BeginLoc = OpRange.getBegin();
Self.Diag(BeginLoc, diag::warn_reinterpret_different_from_static)
  << DerivedType << BaseType << !VirtualBase << int(ReinterpretKind)
  << OpRange;
Self.Diag(BeginLoc, diag::note_reinterpret_updowncast_use_static)
  << int(ReinterpretKind)
  << FixItHint::CreateReplacement(BeginLoc, "static_cast");
1046}

1048static bool argTypeIsABIEquivalent(QualType SrcType, QualType DestType,
                                 ASTContext &Context) {
if (SrcType->isPointerType() && DestType->isPointerType())
  return true;

// Allow integral type mismatch if their size are equal.
if (SrcType->isIntegralType(Context) && DestType->isIntegralType(Context))
  if (Context.getTypeInfoInChars(SrcType).Width ==
      Context.getTypeInfoInChars(DestType).Width)
    return true;

return Context.hasSameUnqualifiedType(SrcType, DestType);
1060}

1062static bool checkCastFunctionType(Sema &Self, const ExprResult &SrcExpr,
                                QualType DestType) {
if (Self.Diags.isIgnored(diag::warn_cast_function_type,
                         SrcExpr.get()->getExprLoc()))
  return true;

QualType SrcType = SrcExpr.get()->getType();
const FunctionType *SrcFTy = nullptr;
const FunctionType *DstFTy = nullptr;
if (((SrcType->isBlockPointerType() || SrcType->isFunctionPointerType()) &&
     DestType->isFunctionPointerType()) ||
    (SrcType->isMemberFunctionPointerType() &&
     DestType->isMemberFunctionPointerType())) {
  SrcFTy = SrcType->getPointeeType()->castAs<FunctionType>();
  DstFTy = DestType->getPointeeType()->castAs<FunctionType>();
} else if (SrcType->isFunctionType() && DestType->isFunctionReferenceType()) {
  SrcFTy = SrcType->castAs<FunctionType>();
  DstFTy = DestType.getNonReferenceType()->castAs<FunctionType>();
} else {
  return true;
}
assert(SrcFTy && DstFTy)((void)0);

auto IsVoidVoid = [](const FunctionType *T) {
  if (!T->getReturnType()->isVoidType())
    return false;
  if (const auto *PT = T->getAs<FunctionProtoType>())
    return !PT->isVariadic() && PT->getNumParams() == 0;
  return false;
};

// Skip if either function type is void(*)(void)
if (IsVoidVoid(SrcFTy) || IsVoidVoid(DstFTy))
  return true;

// Check return type.
if (!argTypeIsABIEquivalent(SrcFTy->getReturnType(), DstFTy->getReturnType(),
                            Self.Context))
  return false;

// Check if either has unspecified number of parameters
if (SrcFTy->isFunctionNoProtoType() || DstFTy->isFunctionNoProtoType())
  return true;

// Check parameter types.

const auto *SrcFPTy = cast<FunctionProtoType>(SrcFTy);
const auto *DstFPTy = cast<FunctionProtoType>(DstFTy);

// In a cast involving function types with a variable argument list only the
// types of initial arguments that are provided are considered.
unsigned NumParams = SrcFPTy->getNumParams();
unsigned DstNumParams = DstFPTy->getNumParams();
if (NumParams > DstNumParams) {
  if (!DstFPTy->isVariadic())
    return false;
  NumParams = DstNumParams;
} else if (NumParams < DstNumParams) {
  if (!SrcFPTy->isVariadic())
    return false;
}

for (unsigned i = 0; i < NumParams; ++i)
  if (!argTypeIsABIEquivalent(SrcFPTy->getParamType(i),
                              DstFPTy->getParamType(i), Self.Context))
    return false;

return true;
1130}

1132/// CheckReinterpretCast - Check that a reinterpret_cast\<DestType\>(SrcExpr) is
1133/// valid.
1134/// Refer to C++ 5.2.10 for details. reinterpret_cast is typically used in code
1135/// like this:
1136/// char *bytes = reinterpret_cast\<char*\>(int_ptr);
1137void CastOperation::CheckReinterpretCast() {
if (ValueKind == VK_PRValue && !isPlaceholder(BuiltinType::Overload))
  SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
else
  checkNonOverloadPlaceholders();
if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
  return;

unsigned msg = diag::err_bad_cxx_cast_generic;
TryCastResult tcr =
  TryReinterpretCast(Self, SrcExpr, DestType,
                     /*CStyle*/false, OpRange, msg, Kind);
if (tcr != TC_Success && msg != 0) {
  if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
    return;
  if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
    //FIXME: &f<int>; is overloaded and resolvable
    Self.Diag(OpRange.getBegin(), diag::err_bad_reinterpret_cast_overload)
      << OverloadExpr::find(SrcExpr.get()).Expression->getName()
      << DestType << OpRange;
    Self.NoteAllOverloadCandidates(SrcExpr.get());

  } else {
    diagnoseBadCast(Self, msg, CT_Reinterpret, OpRange, SrcExpr.get(),
                    DestType, /*listInitialization=*/false);
  }
}

if (isValidCast(tcr)) {
  if (Self.getLangOpts().allowsNonTrivialObjCLifetimeQualifiers())
    checkObjCConversion(Sema::CCK_OtherCast);
  DiagnoseReinterpretUpDownCast(Self, SrcExpr.get(), DestType, OpRange);

  if (!checkCastFunctionType(Self, SrcExpr, DestType))
    Self.Diag(OpRange.getBegin(), diag::warn_cast_function_type)
        << SrcExpr.get()->getType() << DestType << OpRange;
} else {
  SrcExpr = ExprError();
}
1176}


1179/// CheckStaticCast - Check that a static_cast\<DestType\>(SrcExpr) is valid.
1180/// Refer to C++ 5.2.9 for details. Static casts are mostly used for making
1181/// implicit conversions explicit and getting rid of data loss warnings.
1182void CastOperation::CheckStaticCast() {
CheckNoDerefRAII NoderefCheck(*this);

if (isPlaceholder()) {
10
←
Taking false branch→
  checkNonOverloadPlaceholders();
  if (SrcExpr.isInvalid())
    return;
}

// This test is outside everything else because it's the only case where
// a non-lvalue-reference target type does not lead to decay.
// C++ 5.2.9p4: Any expression can be explicitly converted to type "cv void".
if (DestType->isVoidType()) {
11
←
Taking false branch→
  Kind = CK_ToVoid;

  if (claimPlaceholder(BuiltinType::Overload)) {
    Self.ResolveAndFixSingleFunctionTemplateSpecialization(SrcExpr,
              false, // Decay Function to ptr
              true, // Complain
              OpRange, DestType, diag::err_bad_static_cast_overload);
    if (SrcExpr.isInvalid())
      return;
  }

  SrcExpr = Self.IgnoredValueConversions(SrcExpr.get());
  return;
}

if (ValueKind == VK_PRValue && !DestType->isRecordType() &&
12
←
Assuming field 'ValueKind' is not equal to VK_PRValue→
    !isPlaceholder(BuiltinType::Overload)) {
  SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
  if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
    return;
}

unsigned msg = diag::err_bad_cxx_cast_generic;
TryCastResult tcr
  = TryStaticCast(Self, SrcExpr, DestType, Sema::CCK_OtherCast, OpRange, msg,
13
←
Calling 'TryStaticCast'→
                  Kind, BasePath, /*ListInitialization=*/false);
if (tcr != TC_Success && msg != 0) {
  if (SrcExpr.isInvalid())
    return;
  if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
    OverloadExpr* oe = OverloadExpr::find(SrcExpr.get()).Expression;
    Self.Diag(OpRange.getBegin(), diag::err_bad_static_cast_overload)
      << oe->getName() << DestType << OpRange
      << oe->getQualifierLoc().getSourceRange();
    Self.NoteAllOverloadCandidates(SrcExpr.get());
  } else {
    diagnoseBadCast(Self, msg, CT_Static, OpRange, SrcExpr.get(), DestType,
                    /*listInitialization=*/false);
  }
}

if (isValidCast(tcr)) {
  if (Kind == CK_BitCast)
    checkCastAlign();
  if (Self.getLangOpts().allowsNonTrivialObjCLifetimeQualifiers())
    checkObjCConversion(Sema::CCK_OtherCast);
} else {
  SrcExpr = ExprError();
}
1244}

1246static bool IsAddressSpaceConversion(QualType SrcType, QualType DestType) {
auto *SrcPtrType = SrcType->getAs<PointerType>();
if (!SrcPtrType)
  return false;
auto *DestPtrType = DestType->getAs<PointerType>();
if (!DestPtrType)
  return false;
return SrcPtrType->getPointeeType().getAddressSpace() !=
       DestPtrType->getPointeeType().getAddressSpace();
1255}

1257/// TryStaticCast - Check if a static cast can be performed, and do so if
1258/// possible. If @p CStyle, ignore access restrictions on hierarchy casting
1259/// and casting away constness.
1260static TryCastResult TryStaticCast(Sema &Self, ExprResult &SrcExpr,
                                 QualType DestType,
                                 Sema::CheckedConversionKind CCK,
                                 SourceRange OpRange, unsigned &msg,
                                 CastKind &Kind, CXXCastPath &BasePath,
                                 bool ListInitialization) {
// Determine whether we have the semantics of a C-style cast.
bool CStyle
  = (CCK13.1
'CCK' is not equal to CCK_CStyleCast
1
'CCK' is not equal to CCK_CStyleCast
 == Sema::CCK_CStyleCast || CCK == Sema::CCK_FunctionalCast);

// The order the tests is not entirely arbitrary. There is one conversion
// that can be handled in two different ways. Given:
// struct A {};
// struct B : public A {
//   B(); B(const A&);
// };
// const A &a = B();
// the cast static_cast<const B&>(a) could be seen as either a static
// reference downcast, or an explicit invocation of the user-defined
// conversion using B's conversion constructor.
// DR 427 specifies that the downcast is to be applied here.

// C++ 5.2.9p4: Any expression can be explicitly converted to type "cv void".
// Done outside this function.

TryCastResult tcr;

// C++ 5.2.9p5, reference downcast.
// See the function for details.
// DR 427 specifies that this is to be applied before paragraph 2.
tcr = TryStaticReferenceDowncast(Self, SrcExpr.get(), DestType, CStyle,
                                 OpRange, msg, Kind, BasePath);
if (tcr13.2
'tcr' is equal to TC_NotApplicable
2
'tcr' is equal to TC_NotApplicable
 != TC_NotApplicable)
14
←
Taking false branch→
  return tcr;

// C++11 [expr.static.cast]p3:
//   A glvalue of type "cv1 T1" can be cast to type "rvalue reference to cv2
//   T2" if "cv2 T2" is reference-compatible with "cv1 T1".
tcr = TryLValueToRValueCast(Self, SrcExpr.get(), DestType, CStyle, Kind,
                            BasePath, msg);
if (tcr14.1
'tcr' is equal to TC_NotApplicable
1
'tcr' is equal to TC_NotApplicable
 != TC_NotApplicable)
15
←
Taking false branch→
  return tcr;

// C++ 5.2.9p2: An expression e can be explicitly converted to a type T
//   [...] if the declaration "T t(e);" is well-formed, [...].
tcr = TryStaticImplicitCast(Self, SrcExpr, DestType, CCK, OpRange, msg,
                            Kind, ListInitialization);
if (SrcExpr.isInvalid())
16
←
Assuming the condition is false→
17
←
Taking false branch→
  return TC_Failed;
if (tcr17.1
'tcr' is equal to TC_NotApplicable
1
'tcr' is equal to TC_NotApplicable
 != TC_NotApplicable)
18
←
Taking false branch→
  return tcr;

// C++ 5.2.9p6: May apply the reverse of any standard conversion, except
// lvalue-to-rvalue, array-to-pointer, function-to-pointer, and boolean
// conversions, subject to further restrictions.
// Also, C++ 5.2.9p1 forbids casting away constness, which makes reversal
// of qualification conversions impossible.
// In the CStyle case, the earlier attempt to const_cast should have taken
// care of reverse qualification conversions.

QualType SrcType = Self.Context.getCanonicalType(SrcExpr.get()->getType());

// C++0x 5.2.9p9: A value of a scoped enumeration type can be explicitly
// converted to an integral type. [...] A value of a scoped enumeration type
// can also be explicitly converted to a floating-point type [...].
if (const EnumType *Enum19.1
'Enum' is null
1
'Enum' is null
 = SrcType->getAs<EnumType>()) {
19
←
Assuming the object is not a 'EnumType'→
20
←
Taking false branch→
  if (Enum->getDecl()->isScoped()) {
    if (DestType->isBooleanType()) {
      Kind = CK_IntegralToBoolean;
      return TC_Success;
    } else if (DestType->isIntegralType(Self.Context)) {
      Kind = CK_IntegralCast;
      return TC_Success;
    } else if (DestType->isRealFloatingType()) {
      Kind = CK_IntegralToFloating;
      return TC_Success;
    }
  }
}

// Reverse integral promotion/conversion. All such conversions are themselves
// again integral promotions or conversions and are thus already handled by
// p2 (TryDirectInitialization above).
// (Note: any data loss warnings should be suppressed.)
// The exception is the reverse of enum->integer, i.e. integer->enum (and
// enum->enum). See also C++ 5.2.9p7.
// The same goes for reverse floating point promotion/conversion and
// floating-integral conversions. Again, only floating->enum is relevant.
if (DestType->isEnumeralType()) {
21
←
Calling 'Type::isEnumeralType'→
24
←
Returning from 'Type::isEnumeralType'→
25
←
Taking true branch→
  if (Self.RequireCompleteType(OpRange.getBegin(), DestType,
26
←
Assuming the condition is false→
27
←
Taking false branch→
                               diag::err_bad_cast_incomplete)) {
    SrcExpr = ExprError();
    return TC_Failed;
  }
  if (SrcType->isIntegralOrEnumerationType()) {
28
←
Calling 'Type::isIntegralOrEnumerationType'→
38
←
Returning from 'Type::isIntegralOrEnumerationType'→
39
←
Taking true branch→
    // [expr.static.cast]p10 If the enumeration type has a fixed underlying
    // type, the value is first converted to that type by integral conversion
    const EnumType *Enum = DestType->getAs<EnumType>();
40
←
Assuming the object is not a 'EnumType'→
41
←
'Enum' initialized to a null pointer value→
    Kind = Enum->getDecl()->isFixed() &&
42
←
Called C++ object pointer is null
                   Enum->getDecl()->getIntegerType()->isBooleanType()
               ? CK_IntegralToBoolean
               : CK_IntegralCast;
    return TC_Success;
  } else if (SrcType->isRealFloatingType())   {
    Kind = CK_FloatingToIntegral;
    return TC_Success;
  }
}

// Reverse pointer upcast. C++ 4.10p3 specifies pointer upcast.
// C++ 5.2.9p8 additionally disallows a cast path through virtual inheritance.
tcr = TryStaticPointerDowncast(Self, SrcType, DestType, CStyle, OpRange, msg,
                               Kind, BasePath);
if (tcr != TC_NotApplicable)
  return tcr;

// Reverse member pointer conversion. C++ 4.11 specifies member pointer
// conversion. C++ 5.2.9p9 has additional information.
// DR54's access restrictions apply here also.
tcr = TryStaticMemberPointerUpcast(Self, SrcExpr, SrcType, DestType, CStyle,
                                   OpRange, msg, Kind, BasePath);
if (tcr != TC_NotApplicable)
  return tcr;

// Reverse pointer conversion to void*. C++ 4.10.p2 specifies conversion to
// void*. C++ 5.2.9p10 specifies additional restrictions, which really is
// just the usual constness stuff.
if (const PointerType *SrcPointer = SrcType->getAs<PointerType>()) {
  QualType SrcPointee = SrcPointer->getPointeeType();
  if (SrcPointee->isVoidType()) {
    if (const PointerType *DestPointer = DestType->getAs<PointerType>()) {
      QualType DestPointee = DestPointer->getPointeeType();
      if (DestPointee->isIncompleteOrObjectType()) {
        // This is definitely the intended conversion, but it might fail due
        // to a qualifier violation. Note that we permit Objective-C lifetime
        // and GC qualifier mismatches here.
        if (!CStyle) {
          Qualifiers DestPointeeQuals = DestPointee.getQualifiers();
          Qualifiers SrcPointeeQuals = SrcPointee.getQualifiers();
          DestPointeeQuals.removeObjCGCAttr();
          DestPointeeQuals.removeObjCLifetime();
          SrcPointeeQuals.removeObjCGCAttr();
          SrcPointeeQuals.removeObjCLifetime();
          if (DestPointeeQuals != SrcPointeeQuals &&
              !DestPointeeQuals.compatiblyIncludes(SrcPointeeQuals)) {
            msg = diag::err_bad_cxx_cast_qualifiers_away;
            return TC_Failed;
          }
        }
        Kind = IsAddressSpaceConversion(SrcType, DestType)
                   ? CK_AddressSpaceConversion
                   : CK_BitCast;
        return TC_Success;
      }

      // Microsoft permits static_cast from 'pointer-to-void' to
      // 'pointer-to-function'.
      if (!CStyle && Self.getLangOpts().MSVCCompat &&
          DestPointee->isFunctionType()) {
        Self.Diag(OpRange.getBegin(), diag::ext_ms_cast_fn_obj) << OpRange;
        Kind = CK_BitCast;
        return TC_Success;
      }
    }
    else if (DestType->isObjCObjectPointerType()) {
      // allow both c-style cast and static_cast of objective-c pointers as
      // they are pervasive.
      Kind = CK_CPointerToObjCPointerCast;
      return TC_Success;
    }
    else if (CStyle && DestType->isBlockPointerType()) {
      // allow c-style cast of void * to block pointers.
      Kind = CK_AnyPointerToBlockPointerCast;
      return TC_Success;
    }
  }
}
// Allow arbitrary objective-c pointer conversion with static casts.
if (SrcType->isObjCObjectPointerType() &&
    DestType->isObjCObjectPointerType()) {
  Kind = CK_BitCast;
  return TC_Success;
}
// Allow ns-pointer to cf-pointer conversion in either direction
// with static casts.
if (!CStyle &&
    Self.CheckTollFreeBridgeStaticCast(DestType, SrcExpr.get(), Kind))
  return TC_Success;

// See if it looks like the user is trying to convert between
// related record types, and select a better diagnostic if so.
if (auto SrcPointer = SrcType->getAs<PointerType>())
  if (auto DestPointer = DestType->getAs<PointerType>())
    if (SrcPointer->getPointeeType()->getAs<RecordType>() &&
        DestPointer->getPointeeType()->getAs<RecordType>())
     msg = diag::err_bad_cxx_cast_unrelated_class;

if (SrcType->isMatrixType() && DestType->isMatrixType()) {
  if (Self.CheckMatrixCast(OpRange, DestType, SrcType, Kind)) {
    SrcExpr = ExprError();
    return TC_Failed;
  }
  return TC_Success;
}

// We tried everything. Everything! Nothing works! :-(
return TC_NotApplicable;
1467}

1469/// Tests whether a conversion according to N2844 is valid.
1470TryCastResult TryLValueToRValueCast(Sema &Self, Expr *SrcExpr,
                                  QualType DestType, bool CStyle,
                                  CastKind &Kind, CXXCastPath &BasePath,
                                  unsigned &msg) {
// C++11 [expr.static.cast]p3:
//   A glvalue of type "cv1 T1" can be cast to type "rvalue reference to
//   cv2 T2" if "cv2 T2" is reference-compatible with "cv1 T1".
const RValueReferenceType *R = DestType->getAs<RValueReferenceType>();
if (!R)
  return TC_NotApplicable;

if (!SrcExpr->isGLValue())
  return TC_NotApplicable;

// Because we try the reference downcast before this function, from now on
// this is the only cast possibility, so we issue an error if we fail now.
// FIXME: Should allow casting away constness if CStyle.
QualType FromType = SrcExpr->getType();
QualType ToType = R->getPointeeType();
if (CStyle) {
  FromType = FromType.getUnqualifiedType();
  ToType = ToType.getUnqualifiedType();
}

Sema::ReferenceConversions RefConv;
Sema::ReferenceCompareResult RefResult = Self.CompareReferenceRelationship(
    SrcExpr->getBeginLoc(), ToType, FromType, &RefConv);
if (RefResult != Sema::Ref_Compatible) {
  if (CStyle || RefResult == Sema::Ref_Incompatible)
    return TC_NotApplicable;
  // Diagnose types which are reference-related but not compatible here since
  // we can provide better diagnostics. In these cases forwarding to
  // [expr.static.cast]p4 should never result in a well-formed cast.
  msg = SrcExpr->isLValue() ? diag::err_bad_lvalue_to_rvalue_cast
                            : diag::err_bad_rvalue_to_rvalue_cast;
  return TC_Failed;
}

if (RefConv & Sema::ReferenceConversions::DerivedToBase) {
  Kind = CK_DerivedToBase;
  CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
                     /*DetectVirtual=*/true);
  if (!Self.IsDerivedFrom(SrcExpr->getBeginLoc(), SrcExpr->getType(),
                          R->getPointeeType(), Paths))
    return TC_NotApplicable;

  Self.BuildBasePathArray(Paths, BasePath);
} else
  Kind = CK_NoOp;

return TC_Success;
1521}

1523/// Tests whether a conversion according to C++ 5.2.9p5 is valid.
1524TryCastResult
1525TryStaticReferenceDowncast(Sema &Self, Expr *SrcExpr, QualType DestType,
                         bool CStyle, SourceRange OpRange,
                         unsigned &msg, CastKind &Kind,
                         CXXCastPath &BasePath) {
// C++ 5.2.9p5: An lvalue of type "cv1 B", where B is a class type, can be
//   cast to type "reference to cv2 D", where D is a class derived from B,
//   if a valid standard conversion from "pointer to D" to "pointer to B"
//   exists, cv2 >= cv1, and B is not a virtual base class of D.
// In addition, DR54 clarifies that the base must be accessible in the
// current context. Although the wording of DR54 only applies to the pointer
// variant of this rule, the intent is clearly for it to apply to the this
// conversion as well.

const ReferenceType *DestReference = DestType->getAs<ReferenceType>();
if (!DestReference) {
  return TC_NotApplicable;
}
bool RValueRef = DestReference->isRValueReferenceType();
if (!RValueRef && !SrcExpr->isLValue()) {
  // We know the left side is an lvalue reference, so we can suggest a reason.
  msg = diag::err_bad_cxx_cast_rvalue;
  return TC_NotApplicable;
}

QualType DestPointee = DestReference->getPointeeType();

// FIXME: If the source is a prvalue, we should issue a warning (because the
// cast always has undefined behavior), and for AST consistency, we should
// materialize a temporary.
return TryStaticDowncast(Self,
                         Self.Context.getCanonicalType(SrcExpr->getType()),
                         Self.Context.getCanonicalType(DestPointee), CStyle,
                         OpRange, SrcExpr->getType(), DestType, msg, Kind,
                         BasePath);
1559}

1561/// Tests whether a conversion according to C++ 5.2.9p8 is valid.
1562TryCastResult
1563TryStaticPointerDowncast(Sema &Self, QualType SrcType, QualType DestType,
                       bool CStyle, SourceRange OpRange,
                       unsigned &msg, CastKind &Kind,
                       CXXCastPath &BasePath) {
// C++ 5.2.9p8: An rvalue of type "pointer to cv1 B", where B is a class
//   type, can be converted to an rvalue of type "pointer to cv2 D", where D
//   is a class derived from B, if a valid standard conversion from "pointer
//   to D" to "pointer to B" exists, cv2 >= cv1, and B is not a virtual base
//   class of D.
// In addition, DR54 clarifies that the base must be accessible in the
// current context.

const PointerType *DestPointer = DestType->getAs<PointerType>();
if (!DestPointer) {
  return TC_NotApplicable;
}

const PointerType *SrcPointer = SrcType->getAs<PointerType>();
if (!SrcPointer) {
  msg = diag::err_bad_static_cast_pointer_nonpointer;
  return TC_NotApplicable;
}

return TryStaticDowncast(Self,
                 Self.Context.getCanonicalType(SrcPointer->getPointeeType()),
                Self.Context.getCanonicalType(DestPointer->getPointeeType()),
                         CStyle, OpRange, SrcType, DestType, msg, Kind,
                         BasePath);
1591}

1593/// TryStaticDowncast - Common functionality of TryStaticReferenceDowncast and
1594/// TryStaticPointerDowncast. Tests whether a static downcast from SrcType to
1595/// DestType is possible and allowed.
1596TryCastResult
1597TryStaticDowncast(Sema &Self, CanQualType SrcType, CanQualType DestType,
                bool CStyle, SourceRange OpRange, QualType OrigSrcType,
                QualType OrigDestType, unsigned &msg,
                CastKind &Kind, CXXCastPath &BasePath) {
// We can only work with complete types. But don't complain if it doesn't work
if (!Self.isCompleteType(OpRange.getBegin(), SrcType) ||
    !Self.isCompleteType(OpRange.getBegin(), DestType))
  return TC_NotApplicable;

// Downcast can only happen in class hierarchies, so we need classes.
if (!DestType->getAs<RecordType>() || !SrcType->getAs<RecordType>()) {
  return TC_NotApplicable;
}

CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
                   /*DetectVirtual=*/true);
if (!Self.IsDerivedFrom(OpRange.getBegin(), DestType, SrcType, Paths)) {
  return TC_NotApplicable;
}

// Target type does derive from source type. Now we're serious. If an error
// appears now, it's not ignored.
// This may not be entirely in line with the standard. Take for example:
// struct A {};
// struct B : virtual A {
//   B(A&);
// };
//
// void f()
// {
//   (void)static_cast<const B&>(*((A*)0));
// }
// As far as the standard is concerned, p5 does not apply (A is virtual), so
// p2 should be used instead - "const B& t(*((A*)0));" is perfectly valid.
// However, both GCC and Comeau reject this example, and accepting it would
// mean more complex code if we're to preserve the nice error message.
// FIXME: Being 100% compliant here would be nice to have.

// Must preserve cv, as always, unless we're in C-style mode.
if (!CStyle && !DestType.isAtLeastAsQualifiedAs(SrcType)) {
  msg = diag::err_bad_cxx_cast_qualifiers_away;
  return TC_Failed;
}

if (Paths.isAmbiguous(SrcType.getUnqualifiedType())) {
  // This code is analoguous to that in CheckDerivedToBaseConversion, except
  // that it builds the paths in reverse order.
  // To sum up: record all paths to the base and build a nice string from
  // them. Use it to spice up the error message.
  if (!Paths.isRecordingPaths()) {
    Paths.clear();
    Paths.setRecordingPaths(true);
    Self.IsDerivedFrom(OpRange.getBegin(), DestType, SrcType, Paths);
  }
  std::string PathDisplayStr;
  std::set<unsigned> DisplayedPaths;
  for (clang::CXXBasePath &Path : Paths) {
    if (DisplayedPaths.insert(Path.back().SubobjectNumber).second) {
      // We haven't displayed a path to this particular base
      // class subobject yet.
      PathDisplayStr += "\n    ";
      for (CXXBasePathElement &PE : llvm::reverse(Path))
        PathDisplayStr += PE.Base->getType().getAsString() + " -> ";
      PathDisplayStr += QualType(DestType).getAsString();
    }
  }

  Self.Diag(OpRange.getBegin(), diag::err_ambiguous_base_to_derived_cast)
    << QualType(SrcType).getUnqualifiedType()
    << QualType(DestType).getUnqualifiedType()
    << PathDisplayStr << OpRange;
  msg = 0;
  return TC_Failed;
}

if (Paths.getDetectedVirtual() != nullptr) {
  QualType VirtualBase(Paths.getDetectedVirtual(), 0);
  Self.Diag(OpRange.getBegin(), diag::err_static_downcast_via_virtual)
    << OrigSrcType << OrigDestType << VirtualBase << OpRange;
  msg = 0;
  return TC_Failed;
}

if (!CStyle) {
  switch (Self.CheckBaseClassAccess(OpRange.getBegin(),
                                    SrcType, DestType,
                                    Paths.front(),
                              diag::err_downcast_from_inaccessible_base)) {
  case Sema::AR_accessible:
  case Sema::AR_delayed:     // be optimistic
  case Sema::AR_dependent:   // be optimistic
    break;

  case Sema::AR_inaccessible:
    msg = 0;
    return TC_Failed;
  }
}

Self.BuildBasePathArray(Paths, BasePath);
Kind = CK_BaseToDerived;
return TC_Success;
1699}

1701/// TryStaticMemberPointerUpcast - Tests whether a conversion according to
1702/// C++ 5.2.9p9 is valid:
1703///
1704///   An rvalue of type "pointer to member of D of type cv1 T" can be
1705///   converted to an rvalue of type "pointer to member of B of type cv2 T",
1706///   where B is a base class of D [...].
1707///
1708TryCastResult
1709TryStaticMemberPointerUpcast(Sema &Self, ExprResult &SrcExpr, QualType SrcType,
                           QualType DestType, bool CStyle,
                           SourceRange OpRange,
                           unsigned &msg, CastKind &Kind,
                           CXXCastPath &BasePath) {
const MemberPointerType *DestMemPtr = DestType->getAs<MemberPointerType>();
if (!DestMemPtr)
  return TC_NotApplicable;

bool WasOverloadedFunction = false;
DeclAccessPair FoundOverload;
if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
  if (FunctionDecl *Fn
        = Self.ResolveAddressOfOverloadedFunction(SrcExpr.get(), DestType, false,
                                                  FoundOverload)) {
    CXXMethodDecl *M = cast<CXXMethodDecl>(Fn);
    SrcType = Self.Context.getMemberPointerType(Fn->getType(),
                    Self.Context.getTypeDeclType(M->getParent()).getTypePtr());
    WasOverloadedFunction = true;
  }
}

const MemberPointerType *SrcMemPtr = SrcType->getAs<MemberPointerType>();
if (!SrcMemPtr) {
  msg = diag::err_bad_static_cast_member_pointer_nonmp;
  return TC_NotApplicable;
}

// Lock down the inheritance model right now in MS ABI, whether or not the
// pointee types are the same.
if (Self.Context.getTargetInfo().getCXXABI().isMicrosoft()) {
  (void)Self.isCompleteType(OpRange.getBegin(), SrcType);
  (void)Self.isCompleteType(OpRange.getBegin(), DestType);
}

// T == T, modulo cv
if (!Self.Context.hasSameUnqualifiedType(SrcMemPtr->getPointeeType(),
                                         DestMemPtr->getPointeeType()))
  return TC_NotApplicable;

// B base of D
QualType SrcClass(SrcMemPtr->getClass(), 0);
QualType DestClass(DestMemPtr->getClass(), 0);
CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
                /*DetectVirtual=*/true);
if (!Self.IsDerivedFrom(OpRange.getBegin(), SrcClass, DestClass, Paths))
  return TC_NotApplicable;

// B is a base of D. But is it an allowed base? If not, it's a hard error.
if (Paths.isAmbiguous(Self.Context.getCanonicalType(DestClass))) {
  Paths.clear();
  Paths.setRecordingPaths(true);
  bool StillOkay =
      Self.IsDerivedFrom(OpRange.getBegin(), SrcClass, DestClass, Paths);
  assert(StillOkay)((void)0);
  (void)StillOkay;
  std::string PathDisplayStr = Self.getAmbiguousPathsDisplayString(Paths);
  Self.Diag(OpRange.getBegin(), diag::err_ambiguous_memptr_conv)
    << 1 << SrcClass << DestClass << PathDisplayStr << OpRange;
  msg = 0;
  return TC_Failed;
}

if (const RecordType *VBase = Paths.getDetectedVirtual()) {
  Self.Diag(OpRange.getBegin(), diag::err_memptr_conv_via_virtual)
    << SrcClass << DestClass << QualType(VBase, 0) << OpRange;
  msg = 0;
  return TC_Failed;
}

if (!CStyle) {
  switch (Self.CheckBaseClassAccess(OpRange.getBegin(),
                                    DestClass, SrcClass,
                                    Paths.front(),
                                    diag::err_upcast_to_inaccessible_base)) {
  case Sema::AR_accessible:
  case Sema::AR_delayed:
  case Sema::AR_dependent:
    // Optimistically assume that the delayed and dependent cases
    // will work out.
    break;

  case Sema::AR_inaccessible:
    msg = 0;
    return TC_Failed;
  }
}

if (WasOverloadedFunction) {
  // Resolve the address of the overloaded function again, this time
  // allowing complaints if something goes wrong.
  FunctionDecl *Fn = Self.ResolveAddressOfOverloadedFunction(SrcExpr.get(),
                                                             DestType,
                                                             true,
                                                             FoundOverload);
  if (!Fn) {
    msg = 0;
    return TC_Failed;
  }

  SrcExpr = Self.FixOverloadedFunctionReference(SrcExpr, FoundOverload, Fn);
  if (!SrcExpr.isUsable()) {
    msg = 0;
    return TC_Failed;
  }
}

Self.BuildBasePathArray(Paths, BasePath);
Kind = CK_DerivedToBaseMemberPointer;
return TC_Success;
1819}

1821/// TryStaticImplicitCast - Tests whether a conversion according to C++ 5.2.9p2
1822/// is valid:
1823///
1824///   An expression e can be explicitly converted to a type T using a
1825///   @c static_cast if the declaration "T t(e);" is well-formed [...].
1826TryCastResult
1827TryStaticImplicitCast(Sema &Self, ExprResult &SrcExpr, QualType DestType,
                    Sema::CheckedConversionKind CCK,
                    SourceRange OpRange, unsigned &msg,
                    CastKind &Kind, bool ListInitialization) {
if (DestType->isRecordType()) {
  if (Self.RequireCompleteType(OpRange.getBegin(), DestType,
                               diag::err_bad_cast_incomplete) ||
      Self.RequireNonAbstractType(OpRange.getBegin(), DestType,
                                  diag::err_allocation_of_abstract_type)) {
    msg = 0;
    return TC_Failed;
  }
}

InitializedEntity Entity = InitializedEntity::InitializeTemporary(DestType);
InitializationKind InitKind
  = (CCK == Sema::CCK_CStyleCast)
      ? InitializationKind::CreateCStyleCast(OpRange.getBegin(), OpRange,
                                             ListInitialization)
  : (CCK == Sema::CCK_FunctionalCast)
      ? InitializationKind::CreateFunctionalCast(OpRange, ListInitialization)
  : InitializationKind::CreateCast(OpRange);
Expr *SrcExprRaw = SrcExpr.get();
// FIXME: Per DR242, we should check for an implicit conversion sequence
// or for a constructor that could be invoked by direct-initialization
// here, not for an initialization sequence.
InitializationSequence InitSeq(Self, Entity, InitKind, SrcExprRaw);

// At this point of CheckStaticCast, if the destination is a reference,
// or the expression is an overload expression this has to work.
// There is no other way that works.
// On the other hand, if we're checking a C-style cast, we've still got
// the reinterpret_cast way.
bool CStyle
  = (CCK == Sema::CCK_CStyleCast || CCK == Sema::CCK_FunctionalCast);
if (InitSeq.Failed() && (CStyle || !DestType->isReferenceType()))
  return TC_NotApplicable;

ExprResult Result = InitSeq.Perform(Self, Entity, InitKind, SrcExprRaw);
if (Result.isInvalid()) {
  msg = 0;
  return TC_Failed;
}

if (InitSeq.isConstructorInitialization())
  Kind = CK_ConstructorConversion;
else
  Kind = CK_NoOp;

SrcExpr = Result;
return TC_Success;
1878}

1880/// TryConstCast - See if a const_cast from source to destination is allowed,
1881/// and perform it if it is.
1882static TryCastResult TryConstCast(Sema &Self, ExprResult &SrcExpr,
                                QualType DestType, bool CStyle,
                                unsigned &msg) {
DestType = Self.Context.getCanonicalType(DestType);
QualType SrcType = SrcExpr.get()->getType();
bool NeedToMaterializeTemporary = false;

if (const ReferenceType *DestTypeTmp =DestType->getAs<ReferenceType>()) {
  // C++11 5.2.11p4:
  //   if a pointer to T1 can be explicitly converted to the type "pointer to
  //   T2" using a const_cast, then the following conversions can also be
  //   made:
  //    -- an lvalue of type T1 can be explicitly converted to an lvalue of
  //       type T2 using the cast const_cast<T2&>;
  //    -- a glvalue of type T1 can be explicitly converted to an xvalue of
  //       type T2 using the cast const_cast<T2&&>; and
  //    -- if T1 is a class type, a prvalue of type T1 can be explicitly
  //       converted to an xvalue of type T2 using the cast const_cast<T2&&>.

  if (isa<LValueReferenceType>(DestTypeTmp) && !SrcExpr.get()->isLValue()) {
    // Cannot const_cast non-lvalue to lvalue reference type. But if this
    // is C-style, static_cast might find a way, so we simply suggest a
    // message and tell the parent to keep searching.
    msg = diag::err_bad_cxx_cast_rvalue;
    return TC_NotApplicable;
  }

  if (isa<RValueReferenceType>(DestTypeTmp) && SrcExpr.get()->isPRValue()) {
    if (!SrcType->isRecordType()) {
      // Cannot const_cast non-class prvalue to rvalue reference type. But if
      // this is C-style, static_cast can do this.
      msg = diag::err_bad_cxx_cast_rvalue;
      return TC_NotApplicable;
    }

    // Materialize the class prvalue so that the const_cast can bind a
    // reference to it.
    NeedToMaterializeTemporary = true;
  }

  // It's not completely clear under the standard whether we can
  // const_cast bit-field gl-values.  Doing so would not be
  // intrinsically complicated, but for now, we say no for
  // consistency with other compilers and await the word of the
  // committee.
  if (SrcExpr.get()->refersToBitField()) {
    msg = diag::err_bad_cxx_cast_bitfield;
    return TC_NotApplicable;
  }

  DestType = Self.Context.getPointerType(DestTypeTmp->getPointeeType());
  SrcType = Self.Context.getPointerType(SrcType);
}

// C++ 5.2.11p5: For a const_cast involving pointers to data members [...]
//   the rules for const_cast are the same as those used for pointers.

if (!DestType->isPointerType() &&
    !DestType->isMemberPointerType() &&
    !DestType->isObjCObjectPointerType()) {
  // Cannot cast to non-pointer, non-reference type. Note that, if DestType
  // was a reference type, we converted it to a pointer above.
  // The status of rvalue references isn't entirely clear, but it looks like
  // conversion to them is simply invalid.
  // C++ 5.2.11p3: For two pointer types [...]
  if (!CStyle)
    msg = diag::err_bad_const_cast_dest;
  return TC_NotApplicable;
}
if (DestType->isFunctionPointerType() ||
    DestType->isMemberFunctionPointerType()) {
  // Cannot cast direct function pointers.
  // C++ 5.2.11p2: [...] where T is any object type or the void type [...]
  // T is the ultimate pointee of source and target type.
  if (!CStyle)
    msg = diag::err_bad_const_cast_dest;
  return TC_NotApplicable;
}

// C++ [expr.const.cast]p3:
//   "For two similar types T1 and T2, [...]"
//
// We only allow a const_cast to change cvr-qualifiers, not other kinds of
// type qualifiers. (Likewise, we ignore other changes when determining
// whether a cast casts away constness.)
if (!Self.Context.hasCvrSimilarType(SrcType, DestType))
  return TC_NotApplicable;

if (NeedToMaterializeTemporary)
  // This is a const_cast from a class prvalue to an rvalue reference type.
  // Materialize a temporary to store the result of the conversion.
  SrcExpr = Self.CreateMaterializeTemporaryExpr(SrcExpr.get()->getType(),
                                                SrcExpr.get(),
                                                /*IsLValueReference*/ false);

return TC_Success;
1978}

1980// Checks for undefined behavior in reinterpret_cast.
1981// The cases that is checked for is:
1982// *reinterpret_cast<T*>(&a)
1983// reinterpret_cast<T&>(a)
1984// where accessing 'a' as type 'T' will result in undefined behavior.
1985void Sema::CheckCompatibleReinterpretCast(QualType SrcType, QualType DestType,
                                        bool IsDereference,
                                        SourceRange Range) {
unsigned DiagID = IsDereference ?
                      diag::warn_pointer_indirection_from_incompatible_type :
                      diag::warn_undefined_reinterpret_cast;

if (Diags.isIgnored(DiagID, Range.getBegin()))
  return;

QualType SrcTy, DestTy;
if (IsDereference) {
  if (!SrcType->getAs<PointerType>() || !DestType->getAs<PointerType>()) {
    return;
  }
  SrcTy = SrcType->getPointeeType();
  DestTy = DestType->getPointeeType();
} else {
  if (!DestType->getAs<ReferenceType>()) {
    return;
  }
  SrcTy = SrcType;
  DestTy = DestType->getPointeeType();
}

// Cast is compatible if the types are the same.
if (Context.hasSameUnqualifiedType(DestTy, SrcTy)) {
  return;
}
// or one of the types is a char or void type
if (DestTy->isAnyCharacterType() || DestTy->isVoidType() ||
    SrcTy->isAnyCharacterType() || SrcTy->isVoidType()) {
  return;
}
// or one of the types is a tag type.
if (SrcTy->getAs<TagType>() || DestTy->getAs<TagType>()) {
  return;
}

// FIXME: Scoped enums?
if ((SrcTy->isUnsignedIntegerType() && DestTy->isSignedIntegerType()) ||
    (SrcTy->isSignedIntegerType() && DestTy->isUnsignedIntegerType())) {
  if (Context.getTypeSize(DestTy) == Context.getTypeSize(SrcTy)) {
    return;
  }
}

Diag(Range.getBegin(), DiagID) << SrcType << DestType << Range;
2033}

2035static void DiagnoseCastOfObjCSEL(Sema &Self, const ExprResult &SrcExpr,
                                QualType DestType) {
QualType SrcType = SrcExpr.get()->getType();
if (Self.Context.hasSameType(SrcType, DestType))
  return;
if (const PointerType *SrcPtrTy = SrcType->getAs<PointerType>())
  if (SrcPtrTy->isObjCSelType()) {
    QualType DT = DestType;
    if (isa<PointerType>(DestType))
      DT = DestType->getPointeeType();
    if (!DT.getUnqualifiedType()->isVoidType())
      Self.Diag(SrcExpr.get()->getExprLoc(),
                diag::warn_cast_pointer_from_sel)
      << SrcType << DestType << SrcExpr.get()->getSourceRange();
  }
2050}

2052/// Diagnose casts that change the calling convention of a pointer to a function
2053/// defined in the current TU.
2054static void DiagnoseCallingConvCast(Sema &Self, const ExprResult &SrcExpr,
                                  QualType DstType, SourceRange OpRange) {
// Check if this cast would change the calling convention of a function
// pointer type.
QualType SrcType = SrcExpr.get()->getType();
if (Self.Context.hasSameType(SrcType, DstType) ||
    !SrcType->isFunctionPointerType() || !DstType->isFunctionPointerType())
  return;
const auto *SrcFTy =
    SrcType->castAs<PointerType>()->getPointeeType()->castAs<FunctionType>();
const auto *DstFTy =
    DstType->castAs<PointerType>()->getPointeeType()->castAs<FunctionType>();
CallingConv SrcCC = SrcFTy->getCallConv();
CallingConv DstCC = DstFTy->getCallConv();
if (SrcCC == DstCC)
  return;

// We have a calling convention cast. Check if the source is a pointer to a
// known, specific function that has already been defined.
Expr *Src = SrcExpr.get()->IgnoreParenImpCasts();
if (auto *UO = dyn_cast<UnaryOperator>(Src))
  if (UO->getOpcode() == UO_AddrOf)
    Src = UO->getSubExpr()->IgnoreParenImpCasts();
auto *DRE = dyn_cast<DeclRefExpr>(Src);
if (!DRE)
  return;
auto *FD = dyn_cast<FunctionDecl>(DRE->getDecl());
if (!FD)
  return;

// Only warn if we are casting from the default convention to a non-default
// convention. This can happen when the programmer forgot to apply the calling
// convention to the function declaration and then inserted this cast to
// satisfy the type system.
CallingConv DefaultCC = Self.getASTContext().getDefaultCallingConvention(
    FD->isVariadic(), FD->isCXXInstanceMember());
if (DstCC == DefaultCC || SrcCC != DefaultCC)
  return;

// Diagnose this cast, as it is probably bad.
StringRef SrcCCName = FunctionType::getNameForCallConv(SrcCC);
StringRef DstCCName = FunctionType::getNameForCallConv(DstCC);
Self.Diag(OpRange.getBegin(), diag::warn_cast_calling_conv)
    << SrcCCName << DstCCName << OpRange;

// The checks above are cheaper than checking if the diagnostic is enabled.
// However, it's worth checking if the warning is enabled before we construct
// a fixit.
if (Self.Diags.isIgnored(diag::warn_cast_calling_conv, OpRange.getBegin()))
  return;

// Try to suggest a fixit to change the calling convention of the function
// whose address was taken. Try to use the latest macro for the convention.
// For example, users probably want to write "WINAPI" instead of "__stdcall"
// to match the Windows header declarations.
SourceLocation NameLoc = FD->getFirstDecl()->getNameInfo().getLoc();
Preprocessor &PP = Self.getPreprocessor();
SmallVector<TokenValue, 6> AttrTokens;
SmallString<64> CCAttrText;
llvm::raw_svector_ostream OS(CCAttrText);
if (Self.getLangOpts().MicrosoftExt) {
  // __stdcall or __vectorcall
  OS << "__" << DstCCName;
  IdentifierInfo *II = PP.getIdentifierInfo(OS.str());
  AttrTokens.push_back(II->isKeyword(Self.getLangOpts())
                           ? TokenValue(II->getTokenID())
                           : TokenValue(II));
} else {
  // __attribute__((stdcall)) or __attribute__((vectorcall))
  OS << "__attribute__((" << DstCCName << "))";
  AttrTokens.push_back(tok::kw___attribute);
  AttrTokens.push_back(tok::l_paren);
  AttrTokens.push_back(tok::l_paren);
  IdentifierInfo *II = PP.getIdentifierInfo(DstCCName);
  AttrTokens.push_back(II->isKeyword(Self.getLangOpts())
                           ? TokenValue(II->getTokenID())
                           : TokenValue(II));
  AttrTokens.push_back(tok::r_paren);
  AttrTokens.push_back(tok::r_paren);
}
StringRef AttrSpelling = PP.getLastMacroWithSpelling(NameLoc, AttrTokens);
if (!AttrSpelling.empty())
  CCAttrText = AttrSpelling;
OS << ' ';
Self.Diag(NameLoc, diag::note_change_calling_conv_fixit)
    << FD << DstCCName << FixItHint::CreateInsertion(NameLoc, CCAttrText);
2140}

2142static void checkIntToPointerCast(bool CStyle, const SourceRange &OpRange,
                                const Expr *SrcExpr, QualType DestType,
                                Sema &Self) {
QualType SrcType = SrcExpr->getType();

// Not warning on reinterpret_cast, boolean, constant expressions, etc
// are not explicit design choices, but consistent with GCC's behavior.
// Feel free to modify them if you've reason/evidence for an alternative.
if (CStyle && SrcType->isIntegralType(Self.Context)
    && !SrcType->isBooleanType()
    && !SrcType->isEnumeralType()
    && !SrcExpr->isIntegerConstantExpr(Self.Context)
    && Self.Context.getTypeSize(DestType) >
       Self.Context.getTypeSize(SrcType)) {
  // Separate between casts to void* and non-void* pointers.
  // Some APIs use (abuse) void* for something like a user context,
  // and often that value is an integer even if it isn't a pointer itself.
  // Having a separate warning flag allows users to control the warning
  // for their workflow.
  unsigned Diag = DestType->isVoidPointerType() ?
                    diag::warn_int_to_void_pointer_cast
                  : diag::warn_int_to_pointer_cast;
  Self.Diag(OpRange.getBegin(), Diag) << SrcType << DestType << OpRange;
}
2166}

2168static bool fixOverloadedReinterpretCastExpr(Sema &Self, QualType DestType,
                                           ExprResult &Result) {
// We can only fix an overloaded reinterpret_cast if
// - it is a template with explicit arguments that resolves to an lvalue
//   unambiguously, or
// - it is the only function in an overload set that may have its address
//   taken.

Expr *E = Result.get();
// TODO: what if this fails because of DiagnoseUseOfDecl or something
// like it?
if (Self.ResolveAndFixSingleFunctionTemplateSpecialization(
        Result,
        Expr::getValueKindForType(DestType) ==
            VK_PRValue // Convert Fun to Ptr
        ) &&
    Result.isUsable())
  return true;

// No guarantees that ResolveAndFixSingleFunctionTemplateSpecialization
// preserves Result.
Result = E;
if (!Self.resolveAndFixAddressOfSingleOverloadCandidate(
        Result, /*DoFunctionPointerConversion=*/true))
  return false;
return Result.isUsable();
2194}

2196static TryCastResult TryReinterpretCast(Sema &Self, ExprResult &SrcExpr,
                                      QualType DestType, bool CStyle,
                                      SourceRange OpRange,
                                      unsigned &msg,
                                      CastKind &Kind) {
bool IsLValueCast = false;

DestType = Self.Context.getCanonicalType(DestType);
QualType SrcType = SrcExpr.get()->getType();

// Is the source an overloaded name? (i.e. &foo)
// If so, reinterpret_cast generally can not help us here (13.4, p1, bullet 5)
if (SrcType == Self.Context.OverloadTy) {
  ExprResult FixedExpr = SrcExpr;
  if (!fixOverloadedReinterpretCastExpr(Self, DestType, FixedExpr))
    return TC_NotApplicable;

  assert(FixedExpr.isUsable() && "Invalid result fixing overloaded expr")((void)0);
  SrcExpr = FixedExpr;
  SrcType = SrcExpr.get()->getType();
}

if (const ReferenceType *DestTypeTmp = DestType->getAs<ReferenceType>()) {
  if (!SrcExpr.get()->isGLValue()) {
    // Cannot cast non-glvalue to (lvalue or rvalue) reference type. See the
    // similar comment in const_cast.
    msg = diag::err_bad_cxx_cast_rvalue;
    return TC_NotApplicable;
  }

  if (!CStyle) {
    Self.CheckCompatibleReinterpretCast(SrcType, DestType,
                                        /*IsDereference=*/false, OpRange);
  }

  // C++ 5.2.10p10: [...] a reference cast reinterpret_cast<T&>(x) has the
  //   same effect as the conversion *reinterpret_cast<T*>(&x) with the
  //   built-in & and * operators.

  const char *inappropriate = nullptr;
  switch (SrcExpr.get()->getObjectKind()) {
  case OK_Ordinary:
    break;
  case OK_BitField:
    msg = diag::err_bad_cxx_cast_bitfield;
    return TC_NotApplicable;
    // FIXME: Use a specific diagnostic for the rest of these cases.
  case OK_VectorComponent: inappropriate = "vector element";      break;
  case OK_MatrixComponent:
    inappropriate = "matrix element";
    break;
  case OK_ObjCProperty:    inappropriate = "property expression"; break;
  case OK_ObjCSubscript:   inappropriate = "container subscripting expression";
                           break;
  }
  if (inappropriate) {
    Self.Diag(OpRange.getBegin(), diag::err_bad_reinterpret_cast_reference)
        << inappropriate << DestType
        << OpRange << SrcExpr.get()->getSourceRange();
    msg = 0; SrcExpr = ExprError();
    return TC_NotApplicable;
  }

  // This code does this transformation for the checked types.
  DestType = Self.Context.getPointerType(DestTypeTmp->getPointeeType());
  SrcType = Self.Context.getPointerType(SrcType);

  IsLValueCast = true;
}

// Canonicalize source for comparison.
SrcType = Self.Context.getCanonicalType(SrcType);

const MemberPointerType *DestMemPtr = DestType->getAs<MemberPointerType>(),
                        *SrcMemPtr = SrcType->getAs<MemberPointerType>();
if (DestMemPtr && SrcMemPtr) {
  // C++ 5.2.10p9: An rvalue of type "pointer to member of X of type T1"
  //   can be explicitly converted to an rvalue of type "pointer to member
  //   of Y of type T2" if T1 and T2 are both function types or both object
  //   types.
  if (DestMemPtr->isMemberFunctionPointer() !=
      SrcMemPtr->isMemberFunctionPointer())
    return TC_NotApplicable;

  if (Self.Context.getTargetInfo().getCXXABI().isMicrosoft()) {
    // We need to determine the inheritance model that the class will use if
    // haven't yet.
    (void)Self.isCompleteType(OpRange.getBegin(), SrcType);
    (void)Self.isCompleteType(OpRange.getBegin(), DestType);
  }

  // Don't allow casting between member pointers of different sizes.
  if (Self.Context.getTypeSize(DestMemPtr) !=
      Self.Context.getTypeSize(SrcMemPtr)) {
    msg = diag::err_bad_cxx_cast_member_pointer_size;
    return TC_Failed;
  }

  // C++ 5.2.10p2: The reinterpret_cast operator shall not cast away
  //   constness.
  // A reinterpret_cast followed by a const_cast can, though, so in C-style,
  // we accept it.
  if (auto CACK =
          CastsAwayConstness(Self, SrcType, DestType, /*CheckCVR=*/!CStyle,
                             /*CheckObjCLifetime=*/CStyle))
    return getCastAwayConstnessCastKind(CACK, msg);

  // A valid member pointer cast.
  assert(!IsLValueCast)((void)0);
  Kind = CK_ReinterpretMemberPointer;
  return TC_Success;
}

// See below for the enumeral issue.
if (SrcType->isNullPtrType() && DestType->isIntegralType(Self.Context)) {
  // C++0x 5.2.10p4: A pointer can be explicitly converted to any integral
  //   type large enough to hold it. A value of std::nullptr_t can be
  //   converted to an integral type; the conversion has the same meaning
  //   and validity as a conversion of (void*)0 to the integral type.
  if (Self.Context.getTypeSize(SrcType) >
      Self.Context.getTypeSize(DestType)) {
    msg = diag::err_bad_reinterpret_cast_small_int;
    return TC_Failed;
  }
  Kind = CK_PointerToIntegral;
  return TC_Success;
}

// Allow reinterpret_casts between vectors of the same size and
// between vectors and integers of the same size.
bool destIsVector = DestType->isVectorType();
bool srcIsVector = SrcType->isVectorType();
if (srcIsVector || destIsVector) {
  // Allow bitcasting between SVE VLATs and VLSTs, and vice-versa.
  if (Self.isValidSveBitcast(SrcType, DestType)) {
    Kind = CK_BitCast;
    return TC_Success;
  }

  // The non-vector type, if any, must have integral type.  This is
  // the same rule that C vector casts use; note, however, that enum
  // types are not integral in C++.
  if ((!destIsVector && !DestType->isIntegralType(Self.Context)) ||
      (!srcIsVector && !SrcType->isIntegralType(Self.Context)))
    return TC_NotApplicable;

  // The size we want to consider is eltCount * eltSize.
  // That's exactly what the lax-conversion rules will check.
  if (Self.areLaxCompatibleVectorTypes(SrcType, DestType)) {
    Kind = CK_BitCast;
    return TC_Success;
  }

  if (Self.LangOpts.OpenCL && !CStyle) {
    if (DestType->isExtVectorType() || SrcType->isExtVectorType()) {
      // FIXME: Allow for reinterpret cast between 3 and 4 element vectors
      if (Self.areVectorTypesSameSize(SrcType, DestType)) {
        Kind = CK_BitCast;
        return TC_Success;
      }
    }
  }

  // Otherwise, pick a reasonable diagnostic.
  if (!destIsVector)
    msg = diag::err_bad_cxx_cast_vector_to_scalar_different_size;
  else if (!srcIsVector)
    msg = diag::err_bad_cxx_cast_scalar_to_vector_different_size;
  else
    msg = diag::err_bad_cxx_cast_vector_to_vector_different_size;

  return TC_Failed;
}

if (SrcType == DestType) {
  // C++ 5.2.10p2 has a note that mentions that, subject to all other
  // restrictions, a cast to the same type is allowed so long as it does not
  // cast away constness. In C++98, the intent was not entirely clear here,
  // since all other paragraphs explicitly forbid casts to the same type.
  // C++11 clarifies this case with p2.
  //
  // The only allowed types are: integral, enumeration, pointer, or
  // pointer-to-member types.  We also won't restrict Obj-C pointers either.
  Kind = CK_NoOp;
  TryCastResult Result = TC_NotApplicable;
  if (SrcType->isIntegralOrEnumerationType() ||
      SrcType->isAnyPointerType() ||
      SrcType->isMemberPointerType() ||
      SrcType->isBlockPointerType()) {
    Result = TC_Success;
  }
  return Result;
}

bool destIsPtr = DestType->isAnyPointerType() ||
                 DestType->isBlockPointerType();
bool srcIsPtr = SrcType->isAnyPointerType() ||
                SrcType->isBlockPointerType();
if (!destIsPtr && !srcIsPtr) {
  // Except for std::nullptr_t->integer and lvalue->reference, which are
  // handled above, at least one of the two arguments must be a pointer.
  return TC_NotApplicable;
}

if (DestType->isIntegralType(Self.Context)) {
  assert(srcIsPtr && "One type must be a pointer")((void)0);
  // C++ 5.2.10p4: A pointer can be explicitly converted to any integral
  //   type large enough to hold it; except in Microsoft mode, where the
  //   integral type size doesn't matter (except we don't allow bool).
  if ((Self.Context.getTypeSize(SrcType) >
       Self.Context.getTypeSize(DestType))) {
    bool MicrosoftException =
        Self.getLangOpts().MicrosoftExt && !DestType->isBooleanType();
    if (MicrosoftException) {
      unsigned Diag = SrcType->isVoidPointerType()
                          ? diag::warn_void_pointer_to_int_cast
                          : diag::warn_pointer_to_int_cast;
      Self.Diag(OpRange.getBegin(), Diag) << SrcType << DestType << OpRange;
    } else {
      msg = diag::err_bad_reinterpret_cast_small_int;
      return TC_Failed;
    }
  }
  Kind = CK_PointerToIntegral;
  return TC_Success;
}

if (SrcType->isIntegralOrEnumerationType()) {
  assert(destIsPtr && "One type must be a pointer")((void)0);
  checkIntToPointerCast(CStyle, OpRange, SrcExpr.get(), DestType, Self);
  // C++ 5.2.10p5: A value of integral or enumeration type can be explicitly
  //   converted to a pointer.
  // C++ 5.2.10p9: [Note: ...a null pointer constant of integral type is not
  //   necessarily converted to a null pointer value.]
  Kind = CK_IntegralToPointer;
  return TC_Success;
}

if (!destIsPtr || !srcIsPtr) {
  // With the valid non-pointer conversions out of the way, we can be even
  // more stringent.
  return TC_NotApplicable;
}

// Cannot convert between block pointers and Objective-C object pointers.
if ((SrcType->isBlockPointerType() && DestType->isObjCObjectPointerType()) ||
    (DestType->isBlockPointerType() && SrcType->isObjCObjectPointerType()))
  return TC_NotApplicable;

// C++ 5.2.10p2: The reinterpret_cast operator shall not cast away constness.
// The C-style cast operator can.
TryCastResult SuccessResult = TC_Success;
if (auto CACK =
        CastsAwayConstness(Self, SrcType, DestType, /*CheckCVR=*/!CStyle,
                           /*CheckObjCLifetime=*/CStyle))
  SuccessResult = getCastAwayConstnessCastKind(CACK, msg);

if (IsAddressSpaceConversion(SrcType, DestType)) {
  Kind = CK_AddressSpaceConversion;
  assert(SrcType->isPointerType() && DestType->isPointerType())((void)0);
  if (!CStyle &&
      !DestType->getPointeeType().getQualifiers().isAddressSpaceSupersetOf(
          SrcType->getPointeeType().getQualifiers())) {
    SuccessResult = TC_Failed;
  }
} else if (IsLValueCast) {
  Kind = CK_LValueBitCast;
} else if (DestType->isObjCObjectPointerType()) {
  Kind = Self.PrepareCastToObjCObjectPointer(SrcExpr);
} else if (DestType->isBlockPointerType()) {
  if (!SrcType->isBlockPointerType()) {
    Kind = CK_AnyPointerToBlockPointerCast;
  } else {
    Kind = CK_BitCast;
  }
} else {
  Kind = CK_BitCast;
}

// Any pointer can be cast to an Objective-C pointer type with a C-style
// cast.
if (CStyle && DestType->isObjCObjectPointerType()) {
  return SuccessResult;
}
if (CStyle)
  DiagnoseCastOfObjCSEL(Self, SrcExpr, DestType);

DiagnoseCallingConvCast(Self, SrcExpr, DestType, OpRange);

// Not casting away constness, so the only remaining check is for compatible
// pointer categories.

if (SrcType->isFunctionPointerType()) {
  if (DestType->isFunctionPointerType()) {
    // C++ 5.2.10p6: A pointer to a function can be explicitly converted to
    // a pointer to a function of a different type.
    return SuccessResult;
  }

  // C++0x 5.2.10p8: Converting a pointer to a function into a pointer to
  //   an object type or vice versa is conditionally-supported.
  // Compilers support it in C++03 too, though, because it's necessary for
  // casting the return value of dlsym() and GetProcAddress().
  // FIXME: Conditionally-supported behavior should be configurable in the
  // TargetInfo or similar.
  Self.Diag(OpRange.getBegin(),
            Self.getLangOpts().CPlusPlus11 ?
              diag::warn_cxx98_compat_cast_fn_obj : diag::ext_cast_fn_obj)
    << OpRange;
  return SuccessResult;
}

if (DestType->isFunctionPointerType()) {
  // See above.
  Self.Diag(OpRange.getBegin(),
            Self.getLangOpts().CPlusPlus11 ?
              diag::warn_cxx98_compat_cast_fn_obj : diag::ext_cast_fn_obj)
    << OpRange;
  return SuccessResult;
}

// Diagnose address space conversion in nested pointers.
QualType DestPtee = DestType->getPointeeType().isNull()
                        ? DestType->getPointeeType()
                        : DestType->getPointeeType()->getPointeeType();
QualType SrcPtee = SrcType->getPointeeType().isNull()
                       ? SrcType->getPointeeType()
                       : SrcType->getPointeeType()->getPointeeType();
while (!DestPtee.isNull() && !SrcPtee.isNull()) {
  if (DestPtee.getAddressSpace() != SrcPtee.getAddressSpace()) {
    Self.Diag(OpRange.getBegin(),
              diag::warn_bad_cxx_cast_nested_pointer_addr_space)
        << CStyle << SrcType << DestType << SrcExpr.get()->getSourceRange();
    break;
  }
  DestPtee = DestPtee->getPointeeType();
  SrcPtee = SrcPtee->getPointeeType();
}

// C++ 5.2.10p7: A pointer to an object can be explicitly converted to
//   a pointer to an object of different type.
// Void pointers are not specified, but supported by every compiler out there.
// So we finish by allowing everything that remains - it's got to be two
// object pointers.
return SuccessResult;
2541}

2543static TryCastResult TryAddressSpaceCast(Sema &Self, ExprResult &SrcExpr,
                                       QualType DestType, bool CStyle,
                                       unsigned &msg, CastKind &Kind) {
if (!Self.getLangOpts().OpenCL)
  // FIXME: As compiler doesn't have any information about overlapping addr
  // spaces at the moment we have to be permissive here.
  return TC_NotApplicable;
// Even though the logic below is general enough and can be applied to
// non-OpenCL mode too, we fast-path above because no other languages
// define overlapping address spaces currently.
auto SrcType = SrcExpr.get()->getType();
// FIXME: Should this be generalized to references? The reference parameter
// however becomes a reference pointee type here and therefore rejected.
// Perhaps this is the right behavior though according to C++.
auto SrcPtrType = SrcType->getAs<PointerType>();
if (!SrcPtrType)
  return TC_NotApplicable;
auto DestPtrType = DestType->getAs<PointerType>();
if (!DestPtrType)
  return TC_NotApplicable;
auto SrcPointeeType = SrcPtrType->getPointeeType();
auto DestPointeeType = DestPtrType->getPointeeType();
if (!DestPointeeType.isAddressSpaceOverlapping(SrcPointeeType)) {
  msg = diag::err_bad_cxx_cast_addr_space_mismatch;
  return TC_Failed;
}
auto SrcPointeeTypeWithoutAS =
    Self.Context.removeAddrSpaceQualType(SrcPointeeType.getCanonicalType());
auto DestPointeeTypeWithoutAS =
    Self.Context.removeAddrSpaceQualType(DestPointeeType.getCanonicalType());
if (Self.Context.hasSameType(SrcPointeeTypeWithoutAS,
                             DestPointeeTypeWithoutAS)) {
  Kind = SrcPointeeType.getAddressSpace() == DestPointeeType.getAddressSpace()
             ? CK_NoOp
             : CK_AddressSpaceConversion;
  return TC_Success;
} else {
  return TC_NotApplicable;
}
2582}

2584void CastOperation::checkAddressSpaceCast(QualType SrcType, QualType DestType) {
// In OpenCL only conversions between pointers to objects in overlapping
// addr spaces are allowed. v2.0 s6.5.5 - Generic addr space overlaps
// with any named one, except for constant.

// Converting the top level pointee addrspace is permitted for compatible
// addrspaces (such as 'generic int *' to 'local int *' or vice versa), but
// if any of the nested pointee addrspaces differ, we emit a warning
// regardless of addrspace compatibility. This makes
//   local int ** p;
//   return (generic int **) p;
// warn even though local -> generic is permitted.
if (Self.getLangOpts().OpenCL) {
  const Type *DestPtr, *SrcPtr;
  bool Nested = false;
  unsigned DiagID = diag::err_typecheck_incompatible_address_space;
  DestPtr = Self.getASTContext().getCanonicalType(DestType.getTypePtr()),
  SrcPtr  = Self.getASTContext().getCanonicalType(SrcType.getTypePtr());

  while (isa<PointerType>(DestPtr) && isa<PointerType>(SrcPtr)) {
    const PointerType *DestPPtr = cast<PointerType>(DestPtr);
    const PointerType *SrcPPtr = cast<PointerType>(SrcPtr);
    QualType DestPPointee = DestPPtr->getPointeeType();
    QualType SrcPPointee = SrcPPtr->getPointeeType();
    if (Nested
            ? DestPPointee.getAddressSpace() != SrcPPointee.getAddressSpace()
            : !DestPPointee.isAddressSpaceOverlapping(SrcPPointee)) {
      Self.Diag(OpRange.getBegin(), DiagID)
          << SrcType << DestType << Sema::AA_Casting
          << SrcExpr.get()->getSourceRange();
      if (!Nested)
        SrcExpr = ExprError();
      return;
    }

    DestPtr = DestPPtr->getPointeeType().getTypePtr();
    SrcPtr = SrcPPtr->getPointeeType().getTypePtr();
    Nested = true;
    DiagID = diag::ext_nested_pointer_qualifier_mismatch;
  }
}
2625}

2627bool Sema::ShouldSplatAltivecScalarInCast(const VectorType *VecTy) {
bool SrcCompatXL = this->getLangOpts().getAltivecSrcCompat() ==
                   LangOptions::AltivecSrcCompatKind::XL;
VectorType::VectorKind VKind = VecTy->getVectorKind();

if ((VKind == VectorType::AltiVecVector) ||
    (SrcCompatXL && ((VKind == VectorType::AltiVecBool) ||
                     (VKind == VectorType::AltiVecPixel)))) {
  return true;
}
return false;
2638}

2640void CastOperation::CheckCXXCStyleCast(bool FunctionalStyle,
                                     bool ListInitialization) {
assert(Self.getLangOpts().CPlusPlus)((void)0);

// Handle placeholders.
if (isPlaceholder()) {
  // C-style casts can resolve __unknown_any types.
  if (claimPlaceholder(BuiltinType::UnknownAny)) {
    SrcExpr = Self.checkUnknownAnyCast(DestRange, DestType,
                                       SrcExpr.get(), Kind,
                                       ValueKind, BasePath);
    return;
  }

  checkNonOverloadPlaceholders();
  if (SrcExpr.isInvalid())
    return;
}

// C++ 5.2.9p4: Any expression can be explicitly converted to type "cv void".
// This test is outside everything else because it's the only case where
// a non-lvalue-reference target type does not lead to decay.
if (DestType->isVoidType()) {
  Kind = CK_ToVoid;

  if (claimPlaceholder(BuiltinType::Overload)) {
    Self.ResolveAndFixSingleFunctionTemplateSpecialization(
                SrcExpr, /* Decay Function to ptr */ false,
                /* Complain */ true, DestRange, DestType,
                diag::err_bad_cstyle_cast_overload);
    if (SrcExpr.isInvalid())
      return;
  }

  SrcExpr = Self.IgnoredValueConversions(SrcExpr.get());
  return;
}

// If the type is dependent, we won't do any other semantic analysis now.
if (DestType->isDependentType() || SrcExpr.get()->isTypeDependent() ||
    SrcExpr.get()->isValueDependent()) {
  assert(Kind == CK_Dependent)((void)0);
  return;
}

if (ValueKind == VK_PRValue && !DestType->isRecordType() &&
    !isPlaceholder(BuiltinType::Overload)) {
  SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
  if (SrcExpr.isInvalid())
    return;
}

// AltiVec vector initialization with a single literal.
if (const VectorType *vecTy = DestType->getAs<VectorType>())
  if (Self.ShouldSplatAltivecScalarInCast(vecTy) &&
      (SrcExpr.get()->getType()->isIntegerType() ||
       SrcExpr.get()->getType()->isFloatingType())) {
    Kind = CK_VectorSplat;
    SrcExpr = Self.prepareVectorSplat(DestType, SrcExpr.get());
    return;
  }

// C++ [expr.cast]p5: The conversions performed by
//   - a const_cast,
//   - a static_cast,
//   - a static_cast followed by a const_cast,
//   - a reinterpret_cast, or
//   - a reinterpret_cast followed by a const_cast,
//   can be performed using the cast notation of explicit type conversion.
//   [...] If a conversion can be interpreted in more than one of the ways
//   listed above, the interpretation that appears first in the list is used,
//   even if a cast resulting from that interpretation is ill-formed.
// In plain language, this means trying a const_cast ...
// Note that for address space we check compatibility after const_cast.
unsigned msg = diag::err_bad_cxx_cast_generic;
TryCastResult tcr = TryConstCast(Self, SrcExpr, DestType,
                                 /*CStyle*/ true, msg);
if (SrcExpr.isInvalid())
  return;
if (isValidCast(tcr))
  Kind = CK_NoOp;

Sema::CheckedConversionKind CCK =
    FunctionalStyle ? Sema::CCK_FunctionalCast : Sema::CCK_CStyleCast;
if (tcr == TC_NotApplicable) {
  tcr = TryAddressSpaceCast(Self, SrcExpr, DestType, /*CStyle*/ true, msg,
                            Kind);
  if (SrcExpr.isInvalid())
    return;

  if (tcr == TC_NotApplicable) {
    // ... or if that is not possible, a static_cast, ignoring const and
    // addr space, ...
    tcr = TryStaticCast(Self, SrcExpr, DestType, CCK, OpRange, msg, Kind,
                        BasePath, ListInitialization);
    if (SrcExpr.isInvalid())
      return;

    if (tcr == TC_NotApplicable) {
      // ... and finally a reinterpret_cast, ignoring const and addr space.
      tcr = TryReinterpretCast(Self, SrcExpr, DestType, /*CStyle*/ true,
                               OpRange, msg, Kind);
      if (SrcExpr.isInvalid())
        return;
    }
  }
}

if (Self.getLangOpts().allowsNonTrivialObjCLifetimeQualifiers() &&
    isValidCast(tcr))
  checkObjCConversion(CCK);

if (tcr != TC_Success && msg != 0) {
  if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
    DeclAccessPair Found;
    FunctionDecl *Fn = Self.ResolveAddressOfOverloadedFunction(SrcExpr.get(),
                              DestType,
                              /*Complain*/ true,
                              Found);
    if (Fn) {
      // If DestType is a function type (not to be confused with the function
      // pointer type), it will be possible to resolve the function address,
      // but the type cast should be considered as failure.
      OverloadExpr *OE = OverloadExpr::find(SrcExpr.get()).Expression;
      Self.Diag(OpRange.getBegin(), diag::err_bad_cstyle_cast_overload)
        << OE->getName() << DestType << OpRange
        << OE->getQualifierLoc().getSourceRange();
      Self.NoteAllOverloadCandidates(SrcExpr.get());
    }
  } else {
    diagnoseBadCast(Self, msg, (FunctionalStyle ? CT_Functional : CT_CStyle),
                    OpRange, SrcExpr.get(), DestType, ListInitialization);
  }
}

if (isValidCast(tcr)) {
  if (Kind == CK_BitCast)
    checkCastAlign();

  if (!checkCastFunctionType(Self, SrcExpr, DestType))
    Self.Diag(OpRange.getBegin(), diag::warn_cast_function_type)
        << SrcExpr.get()->getType() << DestType << OpRange;

} else {
  SrcExpr = ExprError();
}
2786}

2788/// DiagnoseBadFunctionCast - Warn whenever a function call is cast to a
2789///  non-matching type. Such as enum function call to int, int call to
2790/// pointer; etc. Cast to 'void' is an exception.
2791static void DiagnoseBadFunctionCast(Sema &Self, const ExprResult &SrcExpr,
                                QualType DestType) {
if (Self.Diags.isIgnored(diag::warn_bad_function_cast,
                         SrcExpr.get()->getExprLoc()))
  return;

if (!isa<CallExpr>(SrcExpr.get()))
  return;

QualType SrcType = SrcExpr.get()->getType();
if (DestType.getUnqualifiedType()->isVoidType())
  return;
if ((SrcType->isAnyPointerType() || SrcType->isBlockPointerType())
    && (DestType->isAnyPointerType() || DestType->isBlockPointerType()))
  return;
if (SrcType->isIntegerType() && DestType->isIntegerType() &&
    (SrcType->isBooleanType() == DestType->isBooleanType()) &&
    (SrcType->isEnumeralType() == DestType->isEnumeralType()))
  return;
if (SrcType->isRealFloatingType() && DestType->isRealFloatingType())
  return;
if (SrcType->isEnumeralType() && DestType->isEnumeralType())
  return;
if (SrcType->isComplexType() && DestType->isComplexType())
  return;
if (SrcType->isComplexIntegerType() && DestType->isComplexIntegerType())
  return;
if (SrcType->isFixedPointType() && DestType->isFixedPointType())
  return;

Self.Diag(SrcExpr.get()->getExprLoc(),
          diag::warn_bad_function_cast)
          << SrcType << DestType << SrcExpr.get()->getSourceRange();
2824}

2826/// Check the semantics of a C-style cast operation, in C.
2827void CastOperation::CheckCStyleCast() {
assert(!Self.getLangOpts().CPlusPlus)((void)0);

// C-style casts can resolve __unknown_any types.
if (claimPlaceholder(BuiltinType::UnknownAny)) {
  SrcExpr = Self.checkUnknownAnyCast(DestRange, DestType,
                                     SrcExpr.get(), Kind,
                                     ValueKind, BasePath);
  return;
}

// C99 6.5.4p2: the cast type needs to be void or scalar and the expression
// type needs to be scalar.
if (DestType->isVoidType()) {
  // We don't necessarily do lvalue-to-rvalue conversions on this.
  SrcExpr = Self.IgnoredValueConversions(SrcExpr.get());
  if (SrcExpr.isInvalid())
    return;

  // Cast to void allows any expr type.
  Kind = CK_ToVoid;
  return;
}

// If the type is dependent, we won't do any other semantic analysis now.
if (Self.getASTContext().isDependenceAllowed() &&
    (DestType->isDependentType() || SrcExpr.get()->isTypeDependent() ||
     SrcExpr.get()->isValueDependent())) {
  assert((DestType->containsErrors() || SrcExpr.get()->containsErrors() ||((void)0)
          SrcExpr.get()->containsErrors()) &&((void)0)
         "should only occur in error-recovery path.")((void)0);
  assert(Kind == CK_Dependent)((void)0);
  return;
}

// Overloads are allowed with C extensions, so we need to support them.
if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
  DeclAccessPair DAP;
  if (FunctionDecl *FD = Self.ResolveAddressOfOverloadedFunction(
          SrcExpr.get(), DestType, /*Complain=*/true, DAP))
    SrcExpr = Self.FixOverloadedFunctionReference(SrcExpr.get(), DAP, FD);
  else
    return;
  assert(SrcExpr.isUsable())((void)0);
}
SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
if (SrcExpr.isInvalid())
  return;
QualType SrcType = SrcExpr.get()->getType();

assert(!SrcType->isPlaceholderType())((void)0);

checkAddressSpaceCast(SrcType, DestType);
if (SrcExpr.isInvalid())
  return;

if (Self.RequireCompleteType(OpRange.getBegin(), DestType,
                             diag::err_typecheck_cast_to_incomplete)) {
  SrcExpr = ExprError();
  return;
}

// Allow casting a sizeless built-in type to itself.
if (DestType->isSizelessBuiltinType() &&
    Self.Context.hasSameUnqualifiedType(DestType, SrcType)) {
  Kind = CK_NoOp;
  return;
}

// Allow bitcasting between compatible SVE vector types.
if ((SrcType->isVectorType() || DestType->isVectorType()) &&
    Self.isValidSveBitcast(SrcType, DestType)) {
  Kind = CK_BitCast;
  return;
}

if (!DestType->isScalarType() && !DestType->isVectorType() &&
    !DestType->isMatrixType()) {
  const RecordType *DestRecordTy = DestType->getAs<RecordType>();

  if (DestRecordTy && Self.Context.hasSameUnqualifiedType(DestType, SrcType)){
    // GCC struct/union extension: allow cast to self.
    Self.Diag(OpRange.getBegin(), diag::ext_typecheck_cast_nonscalar)
      << DestType << SrcExpr.get()->getSourceRange();
    Kind = CK_NoOp;
    return;
  }

  // GCC's cast to union extension.
  if (DestRecordTy && DestRecordTy->getDecl()->isUnion()) {
    RecordDecl *RD = DestRecordTy->getDecl();
    if (CastExpr::getTargetFieldForToUnionCast(RD, SrcType)) {
      Self.Diag(OpRange.getBegin(), diag::ext_typecheck_cast_to_union)
        << SrcExpr.get()->getSourceRange();
      Kind = CK_ToUnion;
      return;
    } else {
      Self.Diag(OpRange.getBegin(), diag::err_typecheck_cast_to_union_no_type)
        << SrcType << SrcExpr.get()->getSourceRange();
      SrcExpr = ExprError();
      return;
    }
  }

  // OpenCL v2.0 s6.13.10 - Allow casts from '0' to event_t type.
  if (Self.getLangOpts().OpenCL && DestType->isEventT()) {
    Expr::EvalResult Result;
    if (SrcExpr.get()->EvaluateAsInt(Result, Self.Context)) {
      llvm::APSInt CastInt = Result.Val.getInt();
      if (0 == CastInt) {
        Kind = CK_ZeroToOCLOpaqueType;
        return;
      }
      Self.Diag(OpRange.getBegin(),
                diag::err_opencl_cast_non_zero_to_event_t)
                << toString(CastInt, 10) << SrcExpr.get()->getSourceRange();
      SrcExpr = ExprError();
      return;
    }
  }

  // Reject any other conversions to non-scalar types.
  Self.Diag(OpRange.getBegin(), diag::err_typecheck_cond_expect_scalar)
    << DestType << SrcExpr.get()->getSourceRange();
  SrcExpr = ExprError();
  return;
}

// The type we're casting to is known to be a scalar, a vector, or a matrix.

// Require the operand to be a scalar, a vector, or a matrix.
if (!SrcType->isScalarType() && !SrcType->isVectorType() &&
    !SrcType->isMatrixType()) {
  Self.Diag(SrcExpr.get()->getExprLoc(),
            diag::err_typecheck_expect_scalar_operand)
    << SrcType << SrcExpr.get()->getSourceRange();
  SrcExpr = ExprError();
  return;
}

if (DestType->isExtVectorType()) {
  SrcExpr = Self.CheckExtVectorCast(OpRange, DestType, SrcExpr.get(), Kind);
  return;
}

if (DestType->getAs<MatrixType>() || SrcType->getAs<MatrixType>()) {
  if (Self.CheckMatrixCast(OpRange, DestType, SrcType, Kind))
    SrcExpr = ExprError();
  return;
}

if (const VectorType *DestVecTy = DestType->getAs<VectorType>()) {
  if (Self.ShouldSplatAltivecScalarInCast(DestVecTy) &&
      (SrcType->isIntegerType() || SrcType->isFloatingType())) {
    Kind = CK_VectorSplat;
    SrcExpr = Self.prepareVectorSplat(DestType, SrcExpr.get());
  } else if (Self.CheckVectorCast(OpRange, DestType, SrcType, Kind)) {
    SrcExpr = ExprError();
  }
  return;
}

if (SrcType->isVectorType()) {
  if (Self.CheckVectorCast(OpRange, SrcType, DestType, Kind))
    SrcExpr = ExprError();
  return;
}

// The source and target types are both scalars, i.e.
//   - arithmetic types (fundamental, enum, and complex)
//   - all kinds of pointers
// Note that member pointers were filtered out with C++, above.

if (isa<ObjCSelectorExpr>(SrcExpr.get())) {
  Self.Diag(SrcExpr.get()->getExprLoc(), diag::err_cast_selector_expr);
  SrcExpr = ExprError();
  return;
}

// Can't cast to or from bfloat
if (DestType->isBFloat16Type() && !SrcType->isBFloat16Type()) {
  Self.Diag(SrcExpr.get()->getExprLoc(), diag::err_cast_to_bfloat16)
      << SrcExpr.get()->getSourceRange();
  SrcExpr = ExprError();
  return;
}
if (SrcType->isBFloat16Type() && !DestType->isBFloat16Type()) {
  Self.Diag(SrcExpr.get()->getExprLoc(), diag::err_cast_from_bfloat16)
      << SrcExpr.get()->getSourceRange();
  SrcExpr = ExprError();
  return;
}

// If either type is a pointer, the other type has to be either an
// integer or a pointer.
if (!DestType->isArithmeticType()) {
  if (!SrcType->isIntegralType(Self.Context) && SrcType->isArithmeticType()) {
    Self.Diag(SrcExpr.get()->getExprLoc(),
              diag::err_cast_pointer_from_non_pointer_int)
      << SrcType << SrcExpr.get()->getSourceRange();
    SrcExpr = ExprError();
    return;
  }
  checkIntToPointerCast(/* CStyle */ true, OpRange, SrcExpr.get(), DestType,
                        Self);
} else if (!SrcType->isArithmeticType()) {
  if (!DestType->isIntegralType(Self.Context) &&
      DestType->isArithmeticType()) {
    Self.Diag(SrcExpr.get()->getBeginLoc(),
              diag::err_cast_pointer_to_non_pointer_int)
        << DestType << SrcExpr.get()->getSourceRange();
    SrcExpr = ExprError();
    return;
  }

  if ((Self.Context.getTypeSize(SrcType) >
       Self.Context.getTypeSize(DestType)) &&
      !DestType->isBooleanType()) {
    // C 6.3.2.3p6: Any pointer type may be converted to an integer type.
    // Except as previously specified, the result is implementation-defined.
    // If the result cannot be represented in the integer type, the behavior
    // is undefined. The result need not be in the range of values of any
    // integer type.
    unsigned Diag;
    if (SrcType->isVoidPointerType())
      Diag = DestType->isEnumeralType() ? diag::warn_void_pointer_to_enum_cast
                                        : diag::warn_void_pointer_to_int_cast;
    else if (DestType->isEnumeralType())
      Diag = diag::warn_pointer_to_enum_cast;
    else
      Diag = diag::warn_pointer_to_int_cast;
    Self.Diag(OpRange.getBegin(), Diag) << SrcType << DestType << OpRange;
  }
}

if (Self.getLangOpts().OpenCL && !Self.getOpenCLOptions().isAvailableOption(
                                     "cl_khr_fp16", Self.getLangOpts())) {
  if (DestType->isHalfType()) {
    Self.Diag(SrcExpr.get()->getBeginLoc(), diag::err_opencl_cast_to_half)
        << DestType << SrcExpr.get()->getSourceRange();
    SrcExpr = ExprError();
    return;
  }
}

// ARC imposes extra restrictions on casts.
if (Self.getLangOpts().allowsNonTrivialObjCLifetimeQualifiers()) {
  checkObjCConversion(Sema::CCK_CStyleCast);
  if (SrcExpr.isInvalid())
    return;

  const PointerType *CastPtr = DestType->getAs<PointerType>();
  if (Self.getLangOpts().ObjCAutoRefCount && CastPtr) {
    if (const PointerType *ExprPtr = SrcType->getAs<PointerType>()) {
      Qualifiers CastQuals = CastPtr->getPointeeType().getQualifiers();
      Qualifiers ExprQuals = ExprPtr->getPointeeType().getQualifiers();
      if (CastPtr->getPointeeType()->isObjCLifetimeType() &&
          ExprPtr->getPointeeType()->isObjCLifetimeType() &&
          !CastQuals.compatiblyIncludesObjCLifetime(ExprQuals)) {
        Self.Diag(SrcExpr.get()->getBeginLoc(),
                  diag::err_typecheck_incompatible_ownership)
            << SrcType << DestType << Sema::AA_Casting
            << SrcExpr.get()->getSourceRange();
        return;
      }
    }
  }
  else if (!Self.CheckObjCARCUnavailableWeakConversion(DestType, SrcType)) {
    Self.Diag(SrcExpr.get()->getBeginLoc(),
              diag::err_arc_convesion_of_weak_unavailable)
        << 1 << SrcType << DestType << SrcExpr.get()->getSourceRange();
    SrcExpr = ExprError();
    return;
  }
}

if (!checkCastFunctionType(Self, SrcExpr, DestType))
  Self.Diag(OpRange.getBegin(), diag::warn_cast_function_type)
      << SrcType << DestType << OpRange;

DiagnoseCastOfObjCSEL(Self, SrcExpr, DestType);
DiagnoseCallingConvCast(Self, SrcExpr, DestType, OpRange);
DiagnoseBadFunctionCast(Self, SrcExpr, DestType);
Kind = Self.PrepareScalarCast(SrcExpr, DestType);
if (SrcExpr.isInvalid())
  return;

if (Kind == CK_BitCast)
  checkCastAlign();
3116}

3118void CastOperation::CheckBuiltinBitCast() {
QualType SrcType = SrcExpr.get()->getType();

if (Self.RequireCompleteType(OpRange.getBegin(), DestType,
                             diag::err_typecheck_cast_to_incomplete) ||
    Self.RequireCompleteType(OpRange.getBegin(), SrcType,
                             diag::err_incomplete_type)) {
  SrcExpr = ExprError();
  return;
}

if (SrcExpr.get()->isPRValue())
  SrcExpr = Self.CreateMaterializeTemporaryExpr(SrcType, SrcExpr.get(),
                                                /*IsLValueReference=*/false);

CharUnits DestSize = Self.Context.getTypeSizeInChars(DestType);
CharUnits SourceSize = Self.Context.getTypeSizeInChars(SrcType);
if (DestSize != SourceSize) {
  Self.Diag(OpRange.getBegin(), diag::err_bit_cast_type_size_mismatch)
      << (int)SourceSize.getQuantity() << (int)DestSize.getQuantity();
  SrcExpr = ExprError();
  return;
}

if (!DestType.isTriviallyCopyableType(Self.Context)) {
  Self.Diag(OpRange.getBegin(), diag::err_bit_cast_non_trivially_copyable)
      << 1;
  SrcExpr = ExprError();
  return;
}

if (!SrcType.isTriviallyCopyableType(Self.Context)) {
  Self.Diag(OpRange.getBegin(), diag::err_bit_cast_non_trivially_copyable)
      << 0;
  SrcExpr = ExprError();
  return;
}

Kind = CK_LValueToRValueBitCast;
3157}

3159/// DiagnoseCastQual - Warn whenever casts discards a qualifiers, be it either
3160/// const, volatile or both.
3161static void DiagnoseCastQual(Sema &Self, const ExprResult &SrcExpr,
                           QualType DestType) {
if (SrcExpr.isInvalid())
  return;

QualType SrcType = SrcExpr.get()->getType();
if (!((SrcType->isAnyPointerType() && DestType->isAnyPointerType()) ||
      DestType->isLValueReferenceType()))
  return;

QualType TheOffendingSrcType, TheOffendingDestType;
Qualifiers CastAwayQualifiers;
if (CastsAwayConstness(Self, SrcType, DestType, true, false,
                       &TheOffendingSrcType, &TheOffendingDestType,
                       &CastAwayQualifiers) !=
    CastAwayConstnessKind::CACK_Similar)
  return;

// FIXME: 'restrict' is not properly handled here.
int qualifiers = -1;
if (CastAwayQualifiers.hasConst() && CastAwayQualifiers.hasVolatile()) {
  qualifiers = 0;
} else if (CastAwayQualifiers.hasConst()) {
  qualifiers = 1;
} else if (CastAwayQualifiers.hasVolatile()) {
  qualifiers = 2;
}
// This is a variant of int **x; const int **y = (const int **)x;
if (qualifiers == -1)
  Self.Diag(SrcExpr.get()->getBeginLoc(), diag::warn_cast_qual2)
      << SrcType << DestType;
else
  Self.Diag(SrcExpr.get()->getBeginLoc(), diag::warn_cast_qual)
      << TheOffendingSrcType << TheOffendingDestType << qualifiers;
3195}

3197ExprResult Sema::BuildCStyleCastExpr(SourceLocation LPLoc,
                                   TypeSourceInfo *CastTypeInfo,
                                   SourceLocation RPLoc,
                                   Expr *CastExpr) {
CastOperation Op(*this, CastTypeInfo->getType(), CastExpr);
Op.DestRange = CastTypeInfo->getTypeLoc().getSourceRange();
Op.OpRange = SourceRange(LPLoc, CastExpr->getEndLoc());

if (getLangOpts().CPlusPlus) {
  Op.CheckCXXCStyleCast(/*FunctionalCast=*/ false,
                        isa<InitListExpr>(CastExpr));
} else {
  Op.CheckCStyleCast();
}

if (Op.SrcExpr.isInvalid())
  return ExprError();

// -Wcast-qual
DiagnoseCastQual(Op.Self, Op.SrcExpr, Op.DestType);

return Op.complete(CStyleCastExpr::Create(
    Context, Op.ResultType, Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
    &Op.BasePath, CurFPFeatureOverrides(), CastTypeInfo, LPLoc, RPLoc));
3221}

3223ExprResult Sema::BuildCXXFunctionalCastExpr(TypeSourceInfo *CastTypeInfo,
                                          QualType Type,
                                          SourceLocation LPLoc,
                                          Expr *CastExpr,
                                          SourceLocation RPLoc) {
assert(LPLoc.isValid() && "List-initialization shouldn't get here.")((void)0);
CastOperation Op(*this, Type, CastExpr);
Op.DestRange = CastTypeInfo->getTypeLoc().getSourceRange();
Op.OpRange = SourceRange(Op.DestRange.getBegin(), CastExpr->getEndLoc());

Op.CheckCXXCStyleCast(/*FunctionalCast=*/true, /*ListInit=*/false);
if (Op.SrcExpr.isInvalid())
  return ExprError();

auto *SubExpr = Op.SrcExpr.get();
if (auto *BindExpr = dyn_cast<CXXBindTemporaryExpr>(SubExpr))
  SubExpr = BindExpr->getSubExpr();
if (auto *ConstructExpr = dyn_cast<CXXConstructExpr>(SubExpr))
  ConstructExpr->setParenOrBraceRange(SourceRange(LPLoc, RPLoc));

return Op.complete(CXXFunctionalCastExpr::Create(
    Context, Op.ResultType, Op.ValueKind, CastTypeInfo, Op.Kind,
    Op.SrcExpr.get(), &Op.BasePath, CurFPFeatureOverrides(), LPLoc, RPLoc));
3246}

←

/usr/src/gnu/usr.bin/clang/libclangSema/../../../llvm/clang/include/clang/AST/Type.h

1//===- Type.h - C Language Family Type Representation -----------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9/// \file
10/// C Language Family Type Representation
11///
12/// This file defines the clang::Type interface and subclasses, used to
13/// represent types for languages in the C family.
14//
15//===----------------------------------------------------------------------===//

17#ifndef LLVM_CLANG_AST_TYPE_H
18#define LLVM_CLANG_AST_TYPE_H

20#include "clang/AST/DependenceFlags.h"
21#include "clang/AST/NestedNameSpecifier.h"
22#include "clang/AST/TemplateName.h"
23#include "clang/Basic/AddressSpaces.h"
24#include "clang/Basic/AttrKinds.h"
25#include "clang/Basic/Diagnostic.h"
26#include "clang/Basic/ExceptionSpecificationType.h"
27#include "clang/Basic/LLVM.h"
28#include "clang/Basic/Linkage.h"
29#include "clang/Basic/PartialDiagnostic.h"
30#include "clang/Basic/SourceLocation.h"
31#include "clang/Basic/Specifiers.h"
32#include "clang/Basic/Visibility.h"
33#include "llvm/ADT/APInt.h"
34#include "llvm/ADT/APSInt.h"
35#include "llvm/ADT/ArrayRef.h"
36#include "llvm/ADT/FoldingSet.h"
37#include "llvm/ADT/None.h"
38#include "llvm/ADT/Optional.h"
39#include "llvm/ADT/PointerIntPair.h"
40#include "llvm/ADT/PointerUnion.h"
41#include "llvm/ADT/StringRef.h"
42#include "llvm/ADT/Twine.h"
43#include "llvm/ADT/iterator_range.h"
44#include "llvm/Support/Casting.h"
45#include "llvm/Support/Compiler.h"
46#include "llvm/Support/ErrorHandling.h"
47#include "llvm/Support/PointerLikeTypeTraits.h"
48#include "llvm/Support/TrailingObjects.h"
49#include "llvm/Support/type_traits.h"
50#include <cassert>
51#include <cstddef>
52#include <cstdint>
53#include <cstring>
54#include <string>
55#include <type_traits>
56#include <utility>

58namespace clang {

60class ExtQuals;
61class QualType;
62class ConceptDecl;
63class TagDecl;
64class TemplateParameterList;
65class Type;

67enum {
TypeAlignmentInBits = 4,
TypeAlignment = 1 << TypeAlignmentInBits
70};

72namespace serialization {
template <class T> class AbstractTypeReader;
template <class T> class AbstractTypeWriter;
75}

77} // namespace clang

79namespace llvm {

template <typename T>
struct PointerLikeTypeTraits;
template<>
struct PointerLikeTypeTraits< ::clang::Type*> {
  static inline void *getAsVoidPointer(::clang::Type *P) { return P; }

  static inline ::clang::Type *getFromVoidPointer(void *P) {
    return static_cast< ::clang::Type*>(P);
  }

  static constexpr int NumLowBitsAvailable = clang::TypeAlignmentInBits;
};

template<>
struct PointerLikeTypeTraits< ::clang::ExtQuals*> {
  static inline void *getAsVoidPointer(::clang::ExtQuals *P) { return P; }

  static inline ::clang::ExtQuals *getFromVoidPointer(void *P) {
    return static_cast< ::clang::ExtQuals*>(P);
  }

  static constexpr int NumLowBitsAvailable = clang::TypeAlignmentInBits;
};

105} // namespace llvm

107namespace clang {

109class ASTContext;
110template <typename> class CanQual;
111class CXXRecordDecl;
112class DeclContext;
113class EnumDecl;
114class Expr;
115class ExtQualsTypeCommonBase;
116class FunctionDecl;
117class IdentifierInfo;
118class NamedDecl;
119class ObjCInterfaceDecl;
120class ObjCProtocolDecl;
121class ObjCTypeParamDecl;
122struct PrintingPolicy;
123class RecordDecl;
124class Stmt;
125class TagDecl;
126class TemplateArgument;
127class TemplateArgumentListInfo;
128class TemplateArgumentLoc;
129class TemplateTypeParmDecl;
130class TypedefNameDecl;
131class UnresolvedUsingTypenameDecl;

133using CanQualType = CanQual<Type>;

135// Provide forward declarations for all of the *Type classes.
136#define TYPE(Class, Base) class Class##Type;
137#include "clang/AST/TypeNodes.inc"

139/// The collection of all-type qualifiers we support.
140/// Clang supports five independent qualifiers:
141/// * C99: const, volatile, and restrict
142/// * MS: __unaligned
143/// * Embedded C (TR18037): address spaces
144/// * Objective C: the GC attributes (none, weak, or strong)
145class Qualifiers {
146public:
enum TQ { // NOTE: These flags must be kept in sync with DeclSpec::TQ.
  Const    = 0x1,
  Restrict = 0x2,
  Volatile = 0x4,
  CVRMask = Const | Volatile | Restrict
};

enum GC {
  GCNone = 0,
  Weak,
  Strong
};

enum ObjCLifetime {
  /// There is no lifetime qualification on this type.
  OCL_None,

  /// This object can be modified without requiring retains or
  /// releases.
  OCL_ExplicitNone,

  /// Assigning into this object requires the old value to be
  /// released and the new value to be retained.  The timing of the
  /// release of the old value is inexact: it may be moved to
  /// immediately after the last known point where the value is
  /// live.
  OCL_Strong,

  /// Reading or writing from this object requires a barrier call.
  OCL_Weak,

  /// Assigning into this object requires a lifetime extension.
  OCL_Autoreleasing
};

enum {
  /// The maximum supported address space number.
  /// 23 bits should be enough for anyone.
  MaxAddressSpace = 0x7fffffu,

  /// The width of the "fast" qualifier mask.
  FastWidth = 3,

  /// The fast qualifier mask.
  FastMask = (1 << FastWidth) - 1
};

/// Returns the common set of qualifiers while removing them from
/// the given sets.
static Qualifiers removeCommonQualifiers(Qualifiers &L, Qualifiers &R) {
  // If both are only CVR-qualified, bit operations are sufficient.
  if (!(L.Mask & ~CVRMask) && !(R.Mask & ~CVRMask)) {
    Qualifiers Q;
    Q.Mask = L.Mask & R.Mask;
    L.Mask &= ~Q.Mask;
    R.Mask &= ~Q.Mask;
    return Q;
  }

  Qualifiers Q;
  unsigned CommonCRV = L.getCVRQualifiers() & R.getCVRQualifiers();
  Q.addCVRQualifiers(CommonCRV);
  L.removeCVRQualifiers(CommonCRV);
  R.removeCVRQualifiers(CommonCRV);

  if (L.getObjCGCAttr() == R.getObjCGCAttr()) {
    Q.setObjCGCAttr(L.getObjCGCAttr());
    L.removeObjCGCAttr();
    R.removeObjCGCAttr();
  }

  if (L.getObjCLifetime() == R.getObjCLifetime()) {
    Q.setObjCLifetime(L.getObjCLifetime());
    L.removeObjCLifetime();
    R.removeObjCLifetime();
  }

  if (L.getAddressSpace() == R.getAddressSpace()) {
    Q.setAddressSpace(L.getAddressSpace());
    L.removeAddressSpace();
    R.removeAddressSpace();
  }
  return Q;
}

static Qualifiers fromFastMask(unsigned Mask) {
  Qualifiers Qs;
  Qs.addFastQualifiers(Mask);
  return Qs;
}

static Qualifiers fromCVRMask(unsigned CVR) {
  Qualifiers Qs;
  Qs.addCVRQualifiers(CVR);
  return Qs;
}

static Qualifiers fromCVRUMask(unsigned CVRU) {
  Qualifiers Qs;
  Qs.addCVRUQualifiers(CVRU);
  return Qs;
}

// Deserialize qualifiers from an opaque representation.
static Qualifiers fromOpaqueValue(unsigned opaque) {
  Qualifiers Qs;
  Qs.Mask = opaque;
  return Qs;
}

// Serialize these qualifiers into an opaque representation.
unsigned getAsOpaqueValue() const {
  return Mask;
}

bool hasConst() const { return Mask & Const; }
bool hasOnlyConst() const { return Mask == Const; }
void removeConst() { Mask &= ~Const; }
void addConst() { Mask |= Const; }

bool hasVolatile() const { return Mask & Volatile; }
bool hasOnlyVolatile() const { return Mask == Volatile; }
void removeVolatile() { Mask &= ~Volatile; }
void addVolatile() { Mask |= Volatile; }

bool hasRestrict() const { return Mask & Restrict; }
bool hasOnlyRestrict() const { return Mask == Restrict; }
void removeRestrict() { Mask &= ~Restrict; }
void addRestrict() { Mask |= Restrict; }

bool hasCVRQualifiers() const { return getCVRQualifiers(); }
unsigned getCVRQualifiers() const { return Mask & CVRMask; }
unsigned getCVRUQualifiers() const { return Mask & (CVRMask | UMask); }

void setCVRQualifiers(unsigned mask) {
  assert(!(mask & ~CVRMask) && "bitmask contains non-CVR bits")((void)0);
  Mask = (Mask & ~CVRMask) | mask;
}
void removeCVRQualifiers(unsigned mask) {
  assert(!(mask & ~CVRMask) && "bitmask contains non-CVR bits")((void)0);
  Mask &= ~mask;
}
void removeCVRQualifiers() {
  removeCVRQualifiers(CVRMask);
}
void addCVRQualifiers(unsigned mask) {
  assert(!(mask & ~CVRMask) && "bitmask contains non-CVR bits")((void)0);
  Mask |= mask;
}
void addCVRUQualifiers(unsigned mask) {
  assert(!(mask & ~CVRMask & ~UMask) && "bitmask contains non-CVRU bits")((void)0);
  Mask |= mask;
}

bool hasUnaligned() const { return Mask & UMask; }
void setUnaligned(bool flag) {
  Mask = (Mask & ~UMask) | (flag ? UMask : 0);
}
void removeUnaligned() { Mask &= ~UMask; }
void addUnaligned() { Mask |= UMask; }

bool hasObjCGCAttr() const { return Mask & GCAttrMask; }
GC getObjCGCAttr() const { return GC((Mask & GCAttrMask) >> GCAttrShift); }
void setObjCGCAttr(GC type) {
  Mask = (Mask & ~GCAttrMask) | (type << GCAttrShift);
}
void removeObjCGCAttr() { setObjCGCAttr(GCNone); }
void addObjCGCAttr(GC type) {
  assert(type)((void)0);
  setObjCGCAttr(type);
}
Qualifiers withoutObjCGCAttr() const {
  Qualifiers qs = *this;
  qs.removeObjCGCAttr();
  return qs;
}
Qualifiers withoutObjCLifetime() const {
  Qualifiers qs = *this;
  qs.removeObjCLifetime();
  return qs;
}
Qualifiers withoutAddressSpace() const {
  Qualifiers qs = *this;
  qs.removeAddressSpace();
  return qs;
}

bool hasObjCLifetime() const { return Mask & LifetimeMask; }
ObjCLifetime getObjCLifetime() const {
  return ObjCLifetime((Mask & LifetimeMask) >> LifetimeShift);
}
void setObjCLifetime(ObjCLifetime type) {
  Mask = (Mask & ~LifetimeMask) | (type << LifetimeShift);
}
void removeObjCLifetime() { setObjCLifetime(OCL_None); }
void addObjCLifetime(ObjCLifetime type) {
  assert(type)((void)0);
  assert(!hasObjCLifetime())((void)0);
  Mask |= (type << LifetimeShift);
}

/// True if the lifetime is neither None or ExplicitNone.
bool hasNonTrivialObjCLifetime() const {
  ObjCLifetime lifetime = getObjCLifetime();
  return (lifetime > OCL_ExplicitNone);
}

/// True if the lifetime is either strong or weak.
bool hasStrongOrWeakObjCLifetime() const {
  ObjCLifetime lifetime = getObjCLifetime();
  return (lifetime == OCL_Strong || lifetime == OCL_Weak);
}

bool hasAddressSpace() const { return Mask & AddressSpaceMask; }
LangAS getAddressSpace() const {
  return static_cast<LangAS>(Mask >> AddressSpaceShift);
}
bool hasTargetSpecificAddressSpace() const {
  return isTargetAddressSpace(getAddressSpace());
}
/// Get the address space attribute value to be printed by diagnostics.
unsigned getAddressSpaceAttributePrintValue() const {
  auto Addr = getAddressSpace();
  // This function is not supposed to be used with language specific
  // address spaces. If that happens, the diagnostic message should consider
  // printing the QualType instead of the address space value.
  assert(Addr == LangAS::Default || hasTargetSpecificAddressSpace())((void)0);
  if (Addr != LangAS::Default)
    return toTargetAddressSpace(Addr);
  // TODO: The diagnostic messages where Addr may be 0 should be fixed
  // since it cannot differentiate the situation where 0 denotes the default
  // address space or user specified __attribute__((address_space(0))).
  return 0;
}
void setAddressSpace(LangAS space) {
  assert((unsigned)space <= MaxAddressSpace)((void)0);
  Mask = (Mask & ~AddressSpaceMask)
       | (((uint32_t) space) << AddressSpaceShift);
}
void removeAddressSpace() { setAddressSpace(LangAS::Default); }
void addAddressSpace(LangAS space) {
  assert(space != LangAS::Default)((void)0);
  setAddressSpace(space);
}

// Fast qualifiers are those that can be allocated directly
// on a QualType object.
bool hasFastQualifiers() const { return getFastQualifiers(); }
unsigned getFastQualifiers() const { return Mask & FastMask; }
void setFastQualifiers(unsigned mask) {
  assert(!(mask & ~FastMask) && "bitmask contains non-fast qualifier bits")((void)0);
  Mask = (Mask & ~FastMask) | mask;
}
void removeFastQualifiers(unsigned mask) {
  assert(!(mask & ~FastMask) && "bitmask contains non-fast qualifier bits")((void)0);
  Mask &= ~mask;
}
void removeFastQualifiers() {
  removeFastQualifiers(FastMask);
}
void addFastQualifiers(unsigned mask) {
  assert(!(mask & ~FastMask) && "bitmask contains non-fast qualifier bits")((void)0);
  Mask |= mask;
}

/// Return true if the set contains any qualifiers which require an ExtQuals
/// node to be allocated.
bool hasNonFastQualifiers() const { return Mask & ~FastMask; }
Qualifiers getNonFastQualifiers() const {
  Qualifiers Quals = *this;
  Quals.setFastQualifiers(0);
  return Quals;
}

/// Return true if the set contains any qualifiers.
bool hasQualifiers() const { return Mask; }
bool empty() const { return !Mask; }

/// Add the qualifiers from the given set to this set.
void addQualifiers(Qualifiers Q) {
  // If the other set doesn't have any non-boolean qualifiers, just
  // bit-or it in.
  if (!(Q.Mask & ~CVRMask))
    Mask |= Q.Mask;
  else {
    Mask |= (Q.Mask & CVRMask);
    if (Q.hasAddressSpace())
      addAddressSpace(Q.getAddressSpace());
    if (Q.hasObjCGCAttr())
      addObjCGCAttr(Q.getObjCGCAttr());
    if (Q.hasObjCLifetime())
      addObjCLifetime(Q.getObjCLifetime());
  }
}

/// Remove the qualifiers from the given set from this set.
void removeQualifiers(Qualifiers Q) {
  // If the other set doesn't have any non-boolean qualifiers, just
  // bit-and the inverse in.
  if (!(Q.Mask & ~CVRMask))
    Mask &= ~Q.Mask;
  else {
    Mask &= ~(Q.Mask & CVRMask);
    if (getObjCGCAttr() == Q.getObjCGCAttr())
      removeObjCGCAttr();
    if (getObjCLifetime() == Q.getObjCLifetime())
      removeObjCLifetime();
    if (getAddressSpace() == Q.getAddressSpace())
      removeAddressSpace();
  }
}

/// Add the qualifiers from the given set to this set, given that
/// they don't conflict.
void addConsistentQualifiers(Qualifiers qs) {
  assert(getAddressSpace() == qs.getAddressSpace() ||((void)0)
         !hasAddressSpace() || !qs.hasAddressSpace())((void)0);
  assert(getObjCGCAttr() == qs.getObjCGCAttr() ||((void)0)
         !hasObjCGCAttr() || !qs.hasObjCGCAttr())((void)0);
  assert(getObjCLifetime() == qs.getObjCLifetime() ||((void)0)
         !hasObjCLifetime() || !qs.hasObjCLifetime())((void)0);
  Mask |= qs.Mask;
}

/// Returns true if address space A is equal to or a superset of B.
/// OpenCL v2.0 defines conversion rules (OpenCLC v2.0 s6.5.5) and notion of
/// overlapping address spaces.
/// CL1.1 or CL1.2:
///   every address space is a superset of itself.
/// CL2.0 adds:
///   __generic is a superset of any address space except for __constant.
static bool isAddressSpaceSupersetOf(LangAS A, LangAS B) {
  // Address spaces must match exactly.
  return A == B ||
         // Otherwise in OpenCLC v2.0 s6.5.5: every address space except
         // for __constant can be used as __generic.
         (A == LangAS::opencl_generic && B != LangAS::opencl_constant) ||
         // We also define global_device and global_host address spaces,
         // to distinguish global pointers allocated on host from pointers
         // allocated on device, which are a subset of __global.
         (A == LangAS::opencl_global && (B == LangAS::opencl_global_device ||
                                         B == LangAS::opencl_global_host)) ||
         (A == LangAS::sycl_global && (B == LangAS::sycl_global_device ||
                                       B == LangAS::sycl_global_host)) ||
         // Consider pointer size address spaces to be equivalent to default.
         ((isPtrSizeAddressSpace(A) || A == LangAS::Default) &&
          (isPtrSizeAddressSpace(B) || B == LangAS::Default)) ||
         // Default is a superset of SYCL address spaces.
         (A == LangAS::Default &&
          (B == LangAS::sycl_private || B == LangAS::sycl_local ||
           B == LangAS::sycl_global || B == LangAS::sycl_global_device ||
           B == LangAS::sycl_global_host));
}

/// Returns true if the address space in these qualifiers is equal to or
/// a superset of the address space in the argument qualifiers.
bool isAddressSpaceSupersetOf(Qualifiers other) const {
  return isAddressSpaceSupersetOf(getAddressSpace(), other.getAddressSpace());
}

/// Determines if these qualifiers compatibly include another set.
/// Generally this answers the question of whether an object with the other
/// qualifiers can be safely used as an object with these qualifiers.
bool compatiblyIncludes(Qualifiers other) const {
  return isAddressSpaceSupersetOf(other) &&
         // ObjC GC qualifiers can match, be added, or be removed, but can't
         // be changed.
         (getObjCGCAttr() == other.getObjCGCAttr() || !hasObjCGCAttr() ||
          !other.hasObjCGCAttr()) &&
         // ObjC lifetime qualifiers must match exactly.
         getObjCLifetime() == other.getObjCLifetime() &&
         // CVR qualifiers may subset.
         (((Mask & CVRMask) | (other.Mask & CVRMask)) == (Mask & CVRMask)) &&
         // U qualifier may superset.
         (!other.hasUnaligned() || hasUnaligned());
}

/// Determines if these qualifiers compatibly include another set of
/// qualifiers from the narrow perspective of Objective-C ARC lifetime.
///
/// One set of Objective-C lifetime qualifiers compatibly includes the other
/// if the lifetime qualifiers match, or if both are non-__weak and the
/// including set also contains the 'const' qualifier, or both are non-__weak
/// and one is None (which can only happen in non-ARC modes).
bool compatiblyIncludesObjCLifetime(Qualifiers other) const {
  if (getObjCLifetime() == other.getObjCLifetime())
    return true;

  if (getObjCLifetime() == OCL_Weak || other.getObjCLifetime() == OCL_Weak)
    return false;

  if (getObjCLifetime() == OCL_None || other.getObjCLifetime() == OCL_None)
    return true;

  return hasConst();
}

/// Determine whether this set of qualifiers is a strict superset of
/// another set of qualifiers, not considering qualifier compatibility.
bool isStrictSupersetOf(Qualifiers Other) const;

bool operator==(Qualifiers Other) const { return Mask == Other.Mask; }
bool operator!=(Qualifiers Other) const { return Mask != Other.Mask; }

explicit operator bool() const { return hasQualifiers(); }

Qualifiers &operator+=(Qualifiers R) {
  addQualifiers(R);
  return *this;
}

// Union two qualifier sets.  If an enumerated qualifier appears
// in both sets, use the one from the right.
friend Qualifiers operator+(Qualifiers L, Qualifiers R) {
  L += R;
  return L;
}

Qualifiers &operator-=(Qualifiers R) {
  removeQualifiers(R);
  return *this;
}

/// Compute the difference between two qualifier sets.
friend Qualifiers operator-(Qualifiers L, Qualifiers R) {
  L -= R;
  return L;
}

std::string getAsString() const;
std::string getAsString(const PrintingPolicy &Policy) const;

static std::string getAddrSpaceAsString(LangAS AS);

bool isEmptyWhenPrinted(const PrintingPolicy &Policy) const;
void print(raw_ostream &OS, const PrintingPolicy &Policy,
           bool appendSpaceIfNonEmpty = false) const;

void Profile(llvm::FoldingSetNodeID &ID) const {
  ID.AddInteger(Mask);
}

589private:
// bits:     |0 1 2|3|4 .. 5|6  ..  8|9   ...   31|
//           |C R V|U|GCAttr|Lifetime|AddressSpace|
uint32_t Mask = 0;

static const uint32_t UMask = 0x8;
static const uint32_t UShift = 3;
static const uint32_t GCAttrMask = 0x30;
static const uint32_t GCAttrShift = 4;
static const uint32_t LifetimeMask = 0x1C0;
static const uint32_t LifetimeShift = 6;
static const uint32_t AddressSpaceMask =
    ~(CVRMask | UMask | GCAttrMask | LifetimeMask);
static const uint32_t AddressSpaceShift = 9;
603};

605/// A std::pair-like structure for storing a qualified type split
606/// into its local qualifiers and its locally-unqualified type.
607struct SplitQualType {
/// The locally-unqualified type.
const Type *Ty = nullptr;

/// The local qualifiers.
Qualifiers Quals;

SplitQualType() = default;
SplitQualType(const Type *ty, Qualifiers qs) : Ty(ty), Quals(qs) {}

SplitQualType getSingleStepDesugaredType() const; // end of this file

// Make std::tie work.
std::pair<const Type *,Qualifiers> asPair() const {
  return std::pair<const Type *, Qualifiers>(Ty, Quals);
}

friend bool operator==(SplitQualType a, SplitQualType b) {
  return a.Ty == b.Ty && a.Quals == b.Quals;
}
friend bool operator!=(SplitQualType a, SplitQualType b) {
  return a.Ty != b.Ty || a.Quals != b.Quals;
}
630};

632/// The kind of type we are substituting Objective-C type arguments into.
633///
634/// The kind of substitution affects the replacement of type parameters when
635/// no concrete type information is provided, e.g., when dealing with an
636/// unspecialized type.
637enum class ObjCSubstitutionContext {
/// An ordinary type.
Ordinary,

/// The result type of a method or function.
Result,

/// The parameter type of a method or function.
Parameter,

/// The type of a property.
Property,

/// The superclass of a type.
Superclass,
652};

654/// A (possibly-)qualified type.
655///
656/// For efficiency, we don't store CV-qualified types as nodes on their
657/// own: instead each reference to a type stores the qualifiers.  This
658/// greatly reduces the number of nodes we need to allocate for types (for
659/// example we only need one for 'int', 'const int', 'volatile int',
660/// 'const volatile int', etc).
661///
662/// As an added efficiency bonus, instead of making this a pair, we
663/// just store the two bits we care about in the low bits of the
664/// pointer.  To handle the packing/unpacking, we make QualType be a
665/// simple wrapper class that acts like a smart pointer.  A third bit
666/// indicates whether there are extended qualifiers present, in which
667/// case the pointer points to a special structure.
668class QualType {
friend class QualifierCollector;

// Thankfully, these are efficiently composable.
llvm::PointerIntPair<llvm::PointerUnion<const Type *, const ExtQuals *>,
                     Qualifiers::FastWidth> Value;

const ExtQuals *getExtQualsUnsafe() const {
  return Value.getPointer().get<const ExtQuals*>();
}

const Type *getTypePtrUnsafe() const {
  return Value.getPointer().get<const Type*>();
}

const ExtQualsTypeCommonBase *getCommonPtr() const {
  assert(!isNull() && "Cannot retrieve a NULL type pointer")((void)0);
  auto CommonPtrVal = reinterpret_cast<uintptr_t>(Value.getOpaqueValue());
  CommonPtrVal &= ~(uintptr_t)((1 << TypeAlignmentInBits) - 1);
  return reinterpret_cast<ExtQualsTypeCommonBase*>(CommonPtrVal);
}

690public:
QualType() = default;
QualType(const Type *Ptr, unsigned Quals) : Value(Ptr, Quals) {}
QualType(const ExtQuals *Ptr, unsigned Quals) : Value(Ptr, Quals) {}

unsigned getLocalFastQualifiers() const { return Value.getInt(); }
void setLocalFastQualifiers(unsigned Quals) { Value.setInt(Quals); }

/// Retrieves a pointer to the underlying (unqualified) type.
///
/// This function requires that the type not be NULL. If the type might be
/// NULL, use the (slightly less efficient) \c getTypePtrOrNull().
const Type *getTypePtr() const;

const Type *getTypePtrOrNull() const;

/// Retrieves a pointer to the name of the base type.
const IdentifierInfo *getBaseTypeIdentifier() const;

/// Divides a QualType into its unqualified type and a set of local
/// qualifiers.
SplitQualType split() const;

void *getAsOpaquePtr() const { return Value.getOpaqueValue(); }

static QualType getFromOpaquePtr(const void *Ptr) {
  QualType T;
  T.Value.setFromOpaqueValue(const_cast<void*>(Ptr));
  return T;
}

const Type &operator*() const {
  return *getTypePtr();
}

const Type *operator->() const {
  return getTypePtr();
}

bool isCanonical() const;
bool isCanonicalAsParam() const;

/// Return true if this QualType doesn't point to a type yet.
bool isNull() const {
  return Value.getPointer().isNull();
}

/// Determine whether this particular QualType instance has the
/// "const" qualifier set, without looking through typedefs that may have
/// added "const" at a different level.
bool isLocalConstQualified() const {
  return (getLocalFastQualifiers() & Qualifiers::Const);
}

/// Determine whether this type is const-qualified.
bool isConstQualified() const;

/// Determine whether this particular QualType instance has the
/// "restrict" qualifier set, without looking through typedefs that may have
/// added "restrict" at a different level.
bool isLocalRestrictQualified() const {
  return (getLocalFastQualifiers() & Qualifiers::Restrict);
}

/// Determine whether this type is restrict-qualified.
bool isRestrictQualified() const;

/// Determine whether this particular QualType instance has the
/// "volatile" qualifier set, without looking through typedefs that may have
/// added "volatile" at a different level.
bool isLocalVolatileQualified() const {
  return (getLocalFastQualifiers() & Qualifiers::Volatile);
}

/// Determine whether this type is volatile-qualified.
bool isVolatileQualified() const;

/// Determine whether this particular QualType instance has any
/// qualifiers, without looking through any typedefs that might add
/// qualifiers at a different level.
bool hasLocalQualifiers() const {
  return getLocalFastQualifiers() || hasLocalNonFastQualifiers();
}

/// Determine whether this type has any qualifiers.
bool hasQualifiers() const;

/// Determine whether this particular QualType instance has any
/// "non-fast" qualifiers, e.g., those that are stored in an ExtQualType
/// instance.
bool hasLocalNonFastQualifiers() const {
  return Value.getPointer().is<const ExtQuals*>();
}

/// Retrieve the set of qualifiers local to this particular QualType
/// instance, not including any qualifiers acquired through typedefs or
/// other sugar.
Qualifiers getLocalQualifiers() const;

/// Retrieve the set of qualifiers applied to this type.
Qualifiers getQualifiers() const;

/// Retrieve the set of CVR (const-volatile-restrict) qualifiers
/// local to this particular QualType instance, not including any qualifiers
/// acquired through typedefs or other sugar.
unsigned getLocalCVRQualifiers() const {
  return getLocalFastQualifiers();
}

/// Retrieve the set of CVR (const-volatile-restrict) qualifiers
/// applied to this type.
unsigned getCVRQualifiers() const;

bool isConstant(const ASTContext& Ctx) const {
  return QualType::isConstant(*this, Ctx);
}

/// Determine whether this is a Plain Old Data (POD) type (C++ 3.9p10).
bool isPODType(const ASTContext &Context) const;

/// Return true if this is a POD type according to the rules of the C++98
/// standard, regardless of the current compilation's language.
bool isCXX98PODType(const ASTContext &Context) const;

/// Return true if this is a POD type according to the more relaxed rules
/// of the C++11 standard, regardless of the current compilation's language.
/// (C++0x [basic.types]p9). Note that, unlike
/// CXXRecordDecl::isCXX11StandardLayout, this takes DRs into account.
bool isCXX11PODType(const ASTContext &Context) const;

/// Return true if this is a trivial type per (C++0x [basic.types]p9)
bool isTrivialType(const ASTContext &Context) const;

/// Return true if this is a trivially copyable type (C++0x [basic.types]p9)
bool isTriviallyCopyableType(const ASTContext &Context) const;


/// Returns true if it is a class and it might be dynamic.
bool mayBeDynamicClass() const;

/// Returns true if it is not a class or if the class might not be dynamic.
bool mayBeNotDynamicClass() const;

// Don't promise in the API that anything besides 'const' can be
// easily added.

/// Add the `const` type qualifier to this QualType.
void addConst() {
  addFastQualifiers(Qualifiers::Const);
}
QualType withConst() const {
  return withFastQualifiers(Qualifiers::Const);
}

/// Add the `volatile` type qualifier to this QualType.
void addVolatile() {
  addFastQualifiers(Qualifiers::Volatile);
}
QualType withVolatile() const {
  return withFastQualifiers(Qualifiers::Volatile);
}

/// Add the `restrict` qualifier to this QualType.
void addRestrict() {
  addFastQualifiers(Qualifiers::Restrict);
}
QualType withRestrict() const {
  return withFastQualifiers(Qualifiers::Restrict);
}

QualType withCVRQualifiers(unsigned CVR) const {
  return withFastQualifiers(CVR);
}

void addFastQualifiers(unsigned TQs) {
  assert(!(TQs & ~Qualifiers::FastMask)((void)0)
         && "non-fast qualifier bits set in mask!")((void)0);
  Value.setInt(Value.getInt() | TQs);
}

void removeLocalConst();
void removeLocalVolatile();
void removeLocalRestrict();
void removeLocalCVRQualifiers(unsigned Mask);

void removeLocalFastQualifiers() { Value.setInt(0); }
void removeLocalFastQualifiers(unsigned Mask) {
  assert(!(Mask & ~Qualifiers::FastMask) && "mask has non-fast qualifiers")((void)0);
  Value.setInt(Value.getInt() & ~Mask);
}

// Creates a type with the given qualifiers in addition to any
// qualifiers already on this type.
QualType withFastQualifiers(unsigned TQs) const {
  QualType T = *this;
  T.addFastQualifiers(TQs);
  return T;
}

// Creates a type with exactly the given fast qualifiers, removing
// any existing fast qualifiers.
QualType withExactLocalFastQualifiers(unsigned TQs) const {
  return withoutLocalFastQualifiers().withFastQualifiers(TQs);
}

// Removes fast qualifiers, but leaves any extended qualifiers in place.
QualType withoutLocalFastQualifiers() const {
  QualType T = *this;
  T.removeLocalFastQualifiers();
  return T;
}

QualType getCanonicalType() const;

/// Return this type with all of the instance-specific qualifiers
/// removed, but without removing any qualifiers that may have been applied
/// through typedefs.
QualType getLocalUnqualifiedType() const { return QualType(getTypePtr(), 0); }

/// Retrieve the unqualified variant of the given type,
/// removing as little sugar as possible.
///
/// This routine looks through various kinds of sugar to find the
/// least-desugared type that is unqualified. For example, given:
///
/// \code
/// typedef int Integer;
/// typedef const Integer CInteger;
/// typedef CInteger DifferenceType;
/// \endcode
///
/// Executing \c getUnqualifiedType() on the type \c DifferenceType will
/// desugar until we hit the type \c Integer, which has no qualifiers on it.
///
/// The resulting type might still be qualified if it's sugar for an array
/// type.  To strip qualifiers even from within a sugared array type, use
/// ASTContext::getUnqualifiedArrayType.
inline QualType getUnqualifiedType() const;

/// Retrieve the unqualified variant of the given type, removing as little
/// sugar as possible.
///
/// Like getUnqualifiedType(), but also returns the set of
/// qualifiers that were built up.
///
/// The resulting type might still be qualified if it's sugar for an array
/// type.  To strip qualifiers even from within a sugared array type, use
/// ASTContext::getUnqualifiedArrayType.
inline SplitQualType getSplitUnqualifiedType() const;

/// Determine whether this type is more qualified than the other
/// given type, requiring exact equality for non-CVR qualifiers.
bool isMoreQualifiedThan(QualType Other) const;

/// Determine whether this type is at least as qualified as the other
/// given type, requiring exact equality for non-CVR qualifiers.
bool isAtLeastAsQualifiedAs(QualType Other) const;

QualType getNonReferenceType() const;

/// Determine the type of a (typically non-lvalue) expression with the
/// specified result type.
///
/// This routine should be used for expressions for which the return type is
/// explicitly specified (e.g., in a cast or call) and isn't necessarily
/// an lvalue. It removes a top-level reference (since there are no
/// expressions of reference type) and deletes top-level cvr-qualifiers
/// from non-class types (in C++) or all types (in C).
QualType getNonLValueExprType(const ASTContext &Context) const;

/// Remove an outer pack expansion type (if any) from this type. Used as part
/// of converting the type of a declaration to the type of an expression that
/// references that expression. It's meaningless for an expression to have a
/// pack expansion type.
QualType getNonPackExpansionType() const;

/// Return the specified type with any "sugar" removed from
/// the type.  This takes off typedefs, typeof's etc.  If the outer level of
/// the type is already concrete, it returns it unmodified.  This is similar
/// to getting the canonical type, but it doesn't remove *all* typedefs.  For
/// example, it returns "T*" as "T*", (not as "int*"), because the pointer is
/// concrete.
///
/// Qualifiers are left in place.
QualType getDesugaredType(const ASTContext &Context) const {
  return getDesugaredType(*this, Context);
}

SplitQualType getSplitDesugaredType() const {
  return getSplitDesugaredType(*this);
}

/// Return the specified type with one level of "sugar" removed from
/// the type.
///
/// This routine takes off the first typedef, typeof, etc. If the outer level
/// of the type is already concrete, it returns it unmodified.
QualType getSingleStepDesugaredType(const ASTContext &Context) const {
  return getSingleStepDesugaredTypeImpl(*this, Context);
}

/// Returns the specified type after dropping any
/// outer-level parentheses.
QualType IgnoreParens() const {
  if (isa<ParenType>(*this))
    return QualType::IgnoreParens(*this);
  return *this;
}

/// Indicate whether the specified types and qualifiers are identical.
friend bool operator==(const QualType &LHS, const QualType &RHS) {
  return LHS.Value == RHS.Value;
}
friend bool operator!=(const QualType &LHS, const QualType &RHS) {
  return LHS.Value != RHS.Value;
}
friend bool operator<(const QualType &LHS, const QualType &RHS) {
  return LHS.Value < RHS.Value;
}

static std::string getAsString(SplitQualType split,
                               const PrintingPolicy &Policy) {
  return getAsString(split.Ty, split.Quals, Policy);
}
static std::string getAsString(const Type *ty, Qualifiers qs,
                               const PrintingPolicy &Policy);

std::string getAsString() const;
std::string getAsString(const PrintingPolicy &Policy) const;

void print(raw_ostream &OS, const PrintingPolicy &Policy,
           const Twine &PlaceHolder = Twine(),
           unsigned Indentation = 0) const;

static void print(SplitQualType split, raw_ostream &OS,
                  const PrintingPolicy &policy, const Twine &PlaceHolder,
                  unsigned Indentation = 0) {
  return print(split.Ty, split.Quals, OS, policy, PlaceHolder, Indentation);
}

static void print(const Type *ty, Qualifiers qs,
                  raw_ostream &OS, const PrintingPolicy &policy,
                  const Twine &PlaceHolder,
                  unsigned Indentation = 0);

void getAsStringInternal(std::string &Str,
                         const PrintingPolicy &Policy) const;

static void getAsStringInternal(SplitQualType split, std::string &out,
                                const PrintingPolicy &policy) {
  return getAsStringInternal(split.Ty, split.Quals, out, policy);
}

static void getAsStringInternal(const Type *ty, Qualifiers qs,
                                std::string &out,
                                const PrintingPolicy &policy);

class StreamedQualTypeHelper {
  const QualType &T;
  const PrintingPolicy &Policy;
  const Twine &PlaceHolder;
  unsigned Indentation;

public:
  StreamedQualTypeHelper(const QualType &T, const PrintingPolicy &Policy,
                         const Twine &PlaceHolder, unsigned Indentation)
      : T(T), Policy(Policy), PlaceHolder(PlaceHolder),
        Indentation(Indentation) {}

  friend raw_ostream &operator<<(raw_ostream &OS,
                                 const StreamedQualTypeHelper &SQT) {
    SQT.T.print(OS, SQT.Policy, SQT.PlaceHolder, SQT.Indentation);
    return OS;
  }
};

StreamedQualTypeHelper stream(const PrintingPolicy &Policy,
                              const Twine &PlaceHolder = Twine(),
                              unsigned Indentation = 0) const {
  return StreamedQualTypeHelper(*this, Policy, PlaceHolder, Indentation);
}

void dump(const char *s) const;
void dump() const;
void dump(llvm::raw_ostream &OS, const ASTContext &Context) const;

void Profile(llvm::FoldingSetNodeID &ID) const {
  ID.AddPointer(getAsOpaquePtr());
}

/// Check if this type has any address space qualifier.
inline bool hasAddressSpace() const;

/// Return the address space of this type.
inline LangAS getAddressSpace() const;

/// Returns true if address space qualifiers overlap with T address space
/// qualifiers.
/// OpenCL C defines conversion rules for pointers to different address spaces
/// and notion of overlapping address spaces.
/// CL1.1 or CL1.2:
///   address spaces overlap iff they are they same.
/// OpenCL C v2.0 s6.5.5 adds:
///   __generic overlaps with any address space except for __constant.
bool isAddressSpaceOverlapping(QualType T) const {
  Qualifiers Q = getQualifiers();
  Qualifiers TQ = T.getQualifiers();
  // Address spaces overlap if at least one of them is a superset of another
  return Q.isAddressSpaceSupersetOf(TQ) || TQ.isAddressSpaceSupersetOf(Q);
}

/// Returns gc attribute of this type.
inline Qualifiers::GC getObjCGCAttr() const;

/// true when Type is objc's weak.
bool isObjCGCWeak() const {
  return getObjCGCAttr() == Qualifiers::Weak;
}

/// true when Type is objc's strong.
bool isObjCGCStrong() const {
  return getObjCGCAttr() == Qualifiers::Strong;
}

/// Returns lifetime attribute of this type.
Qualifiers::ObjCLifetime getObjCLifetime() const {
  return getQualifiers().getObjCLifetime();
}

bool hasNonTrivialObjCLifetime() const {
  return getQualifiers().hasNonTrivialObjCLifetime();
}

bool hasStrongOrWeakObjCLifetime() const {
  return getQualifiers().hasStrongOrWeakObjCLifetime();
}

// true when Type is objc's weak and weak is enabled but ARC isn't.
bool isNonWeakInMRRWithObjCWeak(const ASTContext &Context) const;

enum PrimitiveDefaultInitializeKind {
  /// The type does not fall into any of the following categories. Note that
  /// this case is zero-valued so that values of this enum can be used as a
  /// boolean condition for non-triviality.
  PDIK_Trivial,

  /// The type is an Objective-C retainable pointer type that is qualified
  /// with the ARC __strong qualifier.
  PDIK_ARCStrong,

  /// The type is an Objective-C retainable pointer type that is qualified
  /// with the ARC __weak qualifier.
  PDIK_ARCWeak,

  /// The type is a struct containing a field whose type is not PCK_Trivial.
  PDIK_Struct
};

/// Functions to query basic properties of non-trivial C struct types.

/// Check if this is a non-trivial type that would cause a C struct
/// transitively containing this type to be non-trivial to default initialize
/// and return the kind.
PrimitiveDefaultInitializeKind
isNonTrivialToPrimitiveDefaultInitialize() const;

enum PrimitiveCopyKind {
  /// The type does not fall into any of the following categories. Note that
  /// this case is zero-valued so that values of this enum can be used as a
  /// boolean condition for non-triviality.
  PCK_Trivial,

  /// The type would be trivial except that it is volatile-qualified. Types
  /// that fall into one of the other non-trivial cases may additionally be
  /// volatile-qualified.
  PCK_VolatileTrivial,

  /// The type is an Objective-C retainable pointer type that is qualified
  /// with the ARC __strong qualifier.
  PCK_ARCStrong,

  /// The type is an Objective-C retainable pointer type that is qualified
  /// with the ARC __weak qualifier.
  PCK_ARCWeak,

  /// The type is a struct containing a field whose type is neither
  /// PCK_Trivial nor PCK_VolatileTrivial.
  /// Note that a C++ struct type does not necessarily match this; C++ copying
  /// semantics are too complex to express here, in part because they depend
  /// on the exact constructor or assignment operator that is chosen by
  /// overload resolution to do the copy.
  PCK_Struct
};

/// Check if this is a non-trivial type that would cause a C struct
/// transitively containing this type to be non-trivial to copy and return the
/// kind.
PrimitiveCopyKind isNonTrivialToPrimitiveCopy() const;

/// Check if this is a non-trivial type that would cause a C struct
/// transitively containing this type to be non-trivial to destructively
/// move and return the kind. Destructive move in this context is a C++-style
/// move in which the source object is placed in a valid but unspecified state
/// after it is moved, as opposed to a truly destructive move in which the
/// source object is placed in an uninitialized state.
PrimitiveCopyKind isNonTrivialToPrimitiveDestructiveMove() const;

enum DestructionKind {
  DK_none,
  DK_cxx_destructor,
  DK_objc_strong_lifetime,
  DK_objc_weak_lifetime,
  DK_nontrivial_c_struct
};

/// Returns a nonzero value if objects of this type require
/// non-trivial work to clean up after.  Non-zero because it's
/// conceivable that qualifiers (objc_gc(weak)?) could make
/// something require destruction.
DestructionKind isDestructedType() const {
  return isDestructedTypeImpl(*this);
}

/// Check if this is or contains a C union that is non-trivial to
/// default-initialize, which is a union that has a member that is non-trivial
/// to default-initialize. If this returns true,
/// isNonTrivialToPrimitiveDefaultInitialize returns PDIK_Struct.
bool hasNonTrivialToPrimitiveDefaultInitializeCUnion() const;

/// Check if this is or contains a C union that is non-trivial to destruct,
/// which is a union that has a member that is non-trivial to destruct. If
/// this returns true, isDestructedType returns DK_nontrivial_c_struct.
bool hasNonTrivialToPrimitiveDestructCUnion() const;

/// Check if this is or contains a C union that is non-trivial to copy, which
/// is a union that has a member that is non-trivial to copy. If this returns
/// true, isNonTrivialToPrimitiveCopy returns PCK_Struct.
bool hasNonTrivialToPrimitiveCopyCUnion() const;

/// Determine whether expressions of the given type are forbidden
/// from being lvalues in C.
///
/// The expression types that are forbidden to be lvalues are:
///   - 'void', but not qualified void
///   - function types
///
/// The exact rule here is C99 6.3.2.1:
///   An lvalue is an expression with an object type or an incomplete
///   type other than void.
bool isCForbiddenLValueType() const;

/// Substitute type arguments for the Objective-C type parameters used in the
/// subject type.
///
/// \param ctx ASTContext in which the type exists.
///
/// \param typeArgs The type arguments that will be substituted for the
/// Objective-C type parameters in the subject type, which are generally
/// computed via \c Type::getObjCSubstitutions. If empty, the type
/// parameters will be replaced with their bounds or id/Class, as appropriate
/// for the context.
///
/// \param context The context in which the subject type was written.
///
/// \returns the resulting type.
QualType substObjCTypeArgs(ASTContext &ctx,
                           ArrayRef<QualType> typeArgs,
                           ObjCSubstitutionContext context) const;

/// Substitute type arguments from an object type for the Objective-C type
/// parameters used in the subject type.
///
/// This operation combines the computation of type arguments for
/// substitution (\c Type::getObjCSubstitutions) with the actual process of
/// substitution (\c QualType::substObjCTypeArgs) for the convenience of
/// callers that need to perform a single substitution in isolation.
///
/// \param objectType The type of the object whose member type we're
/// substituting into. For example, this might be the receiver of a message
/// or the base of a property access.
///
/// \param dc The declaration context from which the subject type was
/// retrieved, which indicates (for example) which type parameters should
/// be substituted.
///
/// \param context The context in which the subject type was written.
///
/// \returns the subject type after replacing all of the Objective-C type
/// parameters with their corresponding arguments.
QualType substObjCMemberType(QualType objectType,
                             const DeclContext *dc,
                             ObjCSubstitutionContext context) const;

/// Strip Objective-C "__kindof" types from the given type.
QualType stripObjCKindOfType(const ASTContext &ctx) const;

/// Remove all qualifiers including _Atomic.
QualType getAtomicUnqualifiedType() const;

1289private:
// These methods are implemented in a separate translation unit;
// "static"-ize them to avoid creating temporary QualTypes in the
// caller.
static bool isConstant(QualType T, const ASTContext& Ctx);
static QualType getDesugaredType(QualType T, const ASTContext &Context);
static SplitQualType getSplitDesugaredType(QualType T);
static SplitQualType getSplitUnqualifiedTypeImpl(QualType type);
static QualType getSingleStepDesugaredTypeImpl(QualType type,
                                               const ASTContext &C);
static QualType IgnoreParens(QualType T);
static DestructionKind isDestructedTypeImpl(QualType type);

/// Check if \param RD is or contains a non-trivial C union.
static bool hasNonTrivialToPrimitiveDefaultInitializeCUnion(const RecordDecl *RD);
static bool hasNonTrivialToPrimitiveDestructCUnion(const RecordDecl *RD);
static bool hasNonTrivialToPrimitiveCopyCUnion(const RecordDecl *RD);
1306};

1308} // namespace clang

1310namespace llvm {

1312/// Implement simplify_type for QualType, so that we can dyn_cast from QualType
1313/// to a specific Type class.
1314template<> struct simplify_type< ::clang::QualType> {
using SimpleType = const ::clang::Type *;

static SimpleType getSimplifiedValue(::clang::QualType Val) {
  return Val.getTypePtr();
}
1320};

1322// Teach SmallPtrSet that QualType is "basically a pointer".
1323template<>
1324struct PointerLikeTypeTraits<clang::QualType> {
static inline void *getAsVoidPointer(clang::QualType P) {
  return P.getAsOpaquePtr();
}

static inline clang::QualType getFromVoidPointer(void *P) {
  return clang::QualType::getFromOpaquePtr(P);
}

// Various qualifiers go in low bits.
static constexpr int NumLowBitsAvailable = 0;
1335};

1337} // namespace llvm

1339namespace clang {

1341/// Base class that is common to both the \c ExtQuals and \c Type
1342/// classes, which allows \c QualType to access the common fields between the
1343/// two.
1344class ExtQualsTypeCommonBase {
friend class ExtQuals;
friend class QualType;
friend class Type;

/// The "base" type of an extended qualifiers type (\c ExtQuals) or
/// a self-referential pointer (for \c Type).
///
/// This pointer allows an efficient mapping from a QualType to its
/// underlying type pointer.
const Type *const BaseType;

/// The canonical type of this type.  A QualType.
QualType CanonicalType;

ExtQualsTypeCommonBase(const Type *baseType, QualType canon)
    : BaseType(baseType), CanonicalType(canon) {}
1361};

1363/// We can encode up to four bits in the low bits of a
1364/// type pointer, but there are many more type qualifiers that we want
1365/// to be able to apply to an arbitrary type.  Therefore we have this
1366/// struct, intended to be heap-allocated and used by QualType to
1367/// store qualifiers.
1368///
1369/// The current design tags the 'const', 'restrict', and 'volatile' qualifiers
1370/// in three low bits on the QualType pointer; a fourth bit records whether
1371/// the pointer is an ExtQuals node. The extended qualifiers (address spaces,
1372/// Objective-C GC attributes) are much more rare.
1373class ExtQuals : public ExtQualsTypeCommonBase, public llvm::FoldingSetNode {
// NOTE: changing the fast qualifiers should be straightforward as
// long as you don't make 'const' non-fast.
// 1. Qualifiers:
//    a) Modify the bitmasks (Qualifiers::TQ and DeclSpec::TQ).
//       Fast qualifiers must occupy the low-order bits.
//    b) Update Qualifiers::FastWidth and FastMask.
// 2. QualType:
//    a) Update is{Volatile,Restrict}Qualified(), defined inline.
//    b) Update remove{Volatile,Restrict}, defined near the end of
//       this header.
// 3. ASTContext:
//    a) Update get{Volatile,Restrict}Type.

/// The immutable set of qualifiers applied by this node. Always contains
/// extended qualifiers.
Qualifiers Quals;

ExtQuals *this_() { return this; }

1393public:
ExtQuals(const Type *baseType, QualType canon, Qualifiers quals)
    : ExtQualsTypeCommonBase(baseType,
                             canon.isNull() ? QualType(this_(), 0) : canon),
      Quals(quals) {
  assert(Quals.hasNonFastQualifiers()((void)0)
         && "ExtQuals created with no fast qualifiers")((void)0);
  assert(!Quals.hasFastQualifiers()((void)0)
         && "ExtQuals created with fast qualifiers")((void)0);
}

Qualifiers getQualifiers() const { return Quals; }

bool hasObjCGCAttr() const { return Quals.hasObjCGCAttr(); }
Qualifiers::GC getObjCGCAttr() const { return Quals.getObjCGCAttr(); }

bool hasObjCLifetime() const { return Quals.hasObjCLifetime(); }
Qualifiers::ObjCLifetime getObjCLifetime() const {
  return Quals.getObjCLifetime();
}

bool hasAddressSpace() const { return Quals.hasAddressSpace(); }
LangAS getAddressSpace() const { return Quals.getAddressSpace(); }

const Type *getBaseType() const { return BaseType; }

1419public:
void Profile(llvm::FoldingSetNodeID &ID) const {
  Profile(ID, getBaseType(), Quals);
}

static void Profile(llvm::FoldingSetNodeID &ID,
                    const Type *BaseType,
                    Qualifiers Quals) {
  assert(!Quals.hasFastQualifiers() && "fast qualifiers in ExtQuals hash!")((void)0);
  ID.AddPointer(BaseType);
  Quals.Profile(ID);
}
1431};

1433/// The kind of C++11 ref-qualifier associated with a function type.
1434/// This determines whether a member function's "this" object can be an
1435/// lvalue, rvalue, or neither.
1436enum RefQualifierKind {
/// No ref-qualifier was provided.
RQ_None = 0,

/// An lvalue ref-qualifier was provided (\c &).
RQ_LValue,

/// An rvalue ref-qualifier was provided (\c &&).
RQ_RValue
1445};

1447/// Which keyword(s) were used to create an AutoType.
1448enum class AutoTypeKeyword {
/// auto
Auto,

/// decltype(auto)
DecltypeAuto,

/// __auto_type (GNU extension)
GNUAutoType
1457};

1459/// The base class of the type hierarchy.
1460///
1461/// A central concept with types is that each type always has a canonical
1462/// type.  A canonical type is the type with any typedef names stripped out
1463/// of it or the types it references.  For example, consider:
1464///
1465///  typedef int  foo;
1466///  typedef foo* bar;
1467///    'int *'    'foo *'    'bar'
1468///
1469/// There will be a Type object created for 'int'.  Since int is canonical, its
1470/// CanonicalType pointer points to itself.  There is also a Type for 'foo' (a
1471/// TypedefType).  Its CanonicalType pointer points to the 'int' Type.  Next
1472/// there is a PointerType that represents 'int*', which, like 'int', is
1473/// canonical.  Finally, there is a PointerType type for 'foo*' whose canonical
1474/// type is 'int*', and there is a TypedefType for 'bar', whose canonical type
1475/// is also 'int*'.
1476///
1477/// Non-canonical types are useful for emitting diagnostics, without losing
1478/// information about typedefs being used.  Canonical types are useful for type
1479/// comparisons (they allow by-pointer equality tests) and useful for reasoning
1480/// about whether something has a particular form (e.g. is a function type),
1481/// because they implicitly, recursively, strip all typedefs out of a type.
1482///
1483/// Types, once created, are immutable.
1484///
1485class alignas(8) Type : public ExtQualsTypeCommonBase {
1486public:
enum TypeClass {
1488#define TYPE(Class, Base) Class,
1489#define LAST_TYPE(Class) TypeLast = Class
1490#define ABSTRACT_TYPE(Class, Base)
1491#include "clang/AST/TypeNodes.inc"
};

1494private:
/// Bitfields required by the Type class.
class TypeBitfields {
  friend class Type;
  template <class T> friend class TypePropertyCache;

  /// TypeClass bitfield - Enum that specifies what subclass this belongs to.
  unsigned TC : 8;

  /// Store information on the type dependency.
  unsigned Dependence : llvm::BitWidth<TypeDependence>;

  /// True if the cache (i.e. the bitfields here starting with
  /// 'Cache') is valid.
  mutable unsigned CacheValid : 1;

  /// Linkage of this type.
  mutable unsigned CachedLinkage : 3;

  /// Whether this type involves and local or unnamed types.
  mutable unsigned CachedLocalOrUnnamed : 1;

  /// Whether this type comes from an AST file.
  mutable unsigned FromAST : 1;

  bool isCacheValid() const {
    return CacheValid;
  }

  Linkage getLinkage() const {
    assert(isCacheValid() && "getting linkage from invalid cache")((void)0);
    return static_cast<Linkage>(CachedLinkage);
  }

  bool hasLocalOrUnnamedType() const {
    assert(isCacheValid() && "getting linkage from invalid cache")((void)0);
    return CachedLocalOrUnnamed;
  }
};
enum { NumTypeBits = 8 + llvm::BitWidth<TypeDependence> + 6 };

1535protected:
// These classes allow subclasses to somewhat cleanly pack bitfields
// into Type.

class ArrayTypeBitfields {
  friend class ArrayType;

  unsigned : NumTypeBits;

  /// CVR qualifiers from declarations like
  /// 'int X[static restrict 4]'. For function parameters only.
  unsigned IndexTypeQuals : 3;

  /// Storage class qualifiers from declarations like
  /// 'int X[static restrict 4]'. For function parameters only.
  /// Actually an ArrayType::ArraySizeModifier.
  unsigned SizeModifier : 3;
};

class ConstantArrayTypeBitfields {
  friend class ConstantArrayType;

  unsigned : NumTypeBits + 3 + 3;

  /// Whether we have a stored size expression.
  unsigned HasStoredSizeExpr : 1;
};

class BuiltinTypeBitfields {
  friend class BuiltinType;

  unsigned : NumTypeBits;

  /// The kind (BuiltinType::Kind) of builtin type this is.
  unsigned Kind : 8;
};

/// FunctionTypeBitfields store various bits belonging to FunctionProtoType.
/// Only common bits are stored here. Additional uncommon bits are stored
/// in a trailing object after FunctionProtoType.
class FunctionTypeBitfields {
  friend class FunctionProtoType;
  friend class FunctionType;

  unsigned : NumTypeBits;

  /// Extra information which affects how the function is called, like
  /// regparm and the calling convention.
  unsigned ExtInfo : 13;

  /// The ref-qualifier associated with a \c FunctionProtoType.
  ///
  /// This is a value of type \c RefQualifierKind.
  unsigned RefQualifier : 2;

  /// Used only by FunctionProtoType, put here to pack with the
  /// other bitfields.
  /// The qualifiers are part of FunctionProtoType because...
  ///
  /// C++ 8.3.5p4: The return type, the parameter type list and the
  /// cv-qualifier-seq, [...], are part of the function type.
  unsigned FastTypeQuals : Qualifiers::FastWidth;
  /// Whether this function has extended Qualifiers.
  unsigned HasExtQuals : 1;

  /// The number of parameters this function has, not counting '...'.
  /// According to [implimits] 8 bits should be enough here but this is
  /// somewhat easy to exceed with metaprogramming and so we would like to
  /// keep NumParams as wide as reasonably possible.
  unsigned NumParams : 16;

  /// The type of exception specification this function has.
  unsigned ExceptionSpecType : 4;

  /// Whether this function has extended parameter information.
  unsigned HasExtParameterInfos : 1;

  /// Whether the function is variadic.
  unsigned Variadic : 1;

  /// Whether this function has a trailing return type.
  unsigned HasTrailingReturn : 1;
};

class ObjCObjectTypeBitfields {
  friend class ObjCObjectType;

  unsigned : NumTypeBits;

  /// The number of type arguments stored directly on this object type.
  unsigned NumTypeArgs : 7;

  /// The number of protocols stored directly on this object type.
  unsigned NumProtocols : 6;

  /// Whether this is a "kindof" type.
  unsigned IsKindOf : 1;
};

class ReferenceTypeBitfields {
  friend class ReferenceType;

  unsigned : NumTypeBits;

  /// True if the type was originally spelled with an lvalue sigil.
  /// This is never true of rvalue references but can also be false
  /// on lvalue references because of C++0x [dcl.typedef]p9,
  /// as follows:
  ///
  ///   typedef int &ref;    // lvalue, spelled lvalue
  ///   typedef int &&rvref; // rvalue
  ///   ref &a;              // lvalue, inner ref, spelled lvalue
  ///   ref &&a;             // lvalue, inner ref
  ///   rvref &a;            // lvalue, inner ref, spelled lvalue
  ///   rvref &&a;           // rvalue, inner ref
  unsigned SpelledAsLValue : 1;

  /// True if the inner type is a reference type.  This only happens
  /// in non-canonical forms.
  unsigned InnerRef : 1;
};

class TypeWithKeywordBitfields {
  friend class TypeWithKeyword;

  unsigned : NumTypeBits;

  /// An ElaboratedTypeKeyword.  8 bits for efficient access.
  unsigned Keyword : 8;
};

enum { NumTypeWithKeywordBits = 8 };

class ElaboratedTypeBitfields {
  friend class ElaboratedType;

  unsigned : NumTypeBits;
  unsigned : NumTypeWithKeywordBits;

  /// Whether the ElaboratedType has a trailing OwnedTagDecl.
  unsigned HasOwnedTagDecl : 1;
};

class VectorTypeBitfields {
  friend class VectorType;
  friend class DependentVectorType;

  unsigned : NumTypeBits;

  /// The kind of vector, either a generic vector type or some
  /// target-specific vector type such as for AltiVec or Neon.
  unsigned VecKind : 3;
  /// The number of elements in the vector.
  uint32_t NumElements;
};

class AttributedTypeBitfields {
  friend class AttributedType;

  unsigned : NumTypeBits;

  /// An AttributedType::Kind
  unsigned AttrKind : 32 - NumTypeBits;
};

class AutoTypeBitfields {
  friend class AutoType;

  unsigned : NumTypeBits;

  /// Was this placeholder type spelled as 'auto', 'decltype(auto)',
  /// or '__auto_type'?  AutoTypeKeyword value.
  unsigned Keyword : 2;

  /// The number of template arguments in the type-constraints, which is
  /// expected to be able to hold at least 1024 according to [implimits].
  /// However as this limit is somewhat easy to hit with template
  /// metaprogramming we'd prefer to keep it as large as possible.
  /// At the moment it has been left as a non-bitfield since this type
  /// safely fits in 64 bits as an unsigned, so there is no reason to
  /// introduce the performance impact of a bitfield.
  unsigned NumArgs;
};

class SubstTemplateTypeParmPackTypeBitfields {
  friend class SubstTemplateTypeParmPackType;

  unsigned : NumTypeBits;

  /// The number of template arguments in \c Arguments, which is
  /// expected to be able to hold at least 1024 according to [implimits].
  /// However as this limit is somewhat easy to hit with template
  /// metaprogramming we'd prefer to keep it as large as possible.
  /// At the moment it has been left as a non-bitfield since this type
  /// safely fits in 64 bits as an unsigned, so there is no reason to
  /// introduce the performance impact of a bitfield.
  unsigned NumArgs;
};

class TemplateSpecializationTypeBitfields {
  friend class TemplateSpecializationType;

  unsigned : NumTypeBits;

  /// Whether this template specialization type is a substituted type alias.
  unsigned TypeAlias : 1;

  /// The number of template arguments named in this class template
  /// specialization, which is expected to be able to hold at least 1024
  /// according to [implimits]. However, as this limit is somewhat easy to
  /// hit with template metaprogramming we'd prefer to keep it as large
  /// as possible. At the moment it has been left as a non-bitfield since
  /// this type safely fits in 64 bits as an unsigned, so there is no reason
  /// to introduce the performance impact of a bitfield.
  unsigned NumArgs;
};

class DependentTemplateSpecializationTypeBitfields {
  friend class DependentTemplateSpecializationType;

  unsigned : NumTypeBits;
  unsigned : NumTypeWithKeywordBits;

  /// The number of template arguments named in this class template
  /// specialization, which is expected to be able to hold at least 1024
  /// according to [implimits]. However, as this limit is somewhat easy to
  /// hit with template metaprogramming we'd prefer to keep it as large
  /// as possible. At the moment it has been left as a non-bitfield since
  /// this type safely fits in 64 bits as an unsigned, so there is no reason
  /// to introduce the performance impact of a bitfield.
  unsigned NumArgs;
};

class PackExpansionTypeBitfields {
  friend class PackExpansionType;

  unsigned : NumTypeBits;

  /// The number of expansions that this pack expansion will
  /// generate when substituted (+1), which is expected to be able to
  /// hold at least 1024 according to [implimits]. However, as this limit
  /// is somewhat easy to hit with template metaprogramming we'd prefer to
  /// keep it as large as possible. At the moment it has been left as a
  /// non-bitfield since this type safely fits in 64 bits as an unsigned, so
  /// there is no reason to introduce the performance impact of a bitfield.
  ///
  /// This field will only have a non-zero value when some of the parameter
  /// packs that occur within the pattern have been substituted but others
  /// have not.
  unsigned NumExpansions;
};

union {
  TypeBitfields TypeBits;
  ArrayTypeBitfields ArrayTypeBits;
  ConstantArrayTypeBitfields ConstantArrayTypeBits;
  AttributedTypeBitfields AttributedTypeBits;
  AutoTypeBitfields AutoTypeBits;
  BuiltinTypeBitfields BuiltinTypeBits;
  FunctionTypeBitfields FunctionTypeBits;
  ObjCObjectTypeBitfields ObjCObjectTypeBits;
  ReferenceTypeBitfields ReferenceTypeBits;
  TypeWithKeywordBitfields TypeWithKeywordBits;
  ElaboratedTypeBitfields ElaboratedTypeBits;
  VectorTypeBitfields VectorTypeBits;
  SubstTemplateTypeParmPackTypeBitfields SubstTemplateTypeParmPackTypeBits;
  TemplateSpecializationTypeBitfields TemplateSpecializationTypeBits;
  DependentTemplateSpecializationTypeBitfields
    DependentTemplateSpecializationTypeBits;
  PackExpansionTypeBitfields PackExpansionTypeBits;
};

1807private:
template <class T> friend class TypePropertyCache;

/// Set whether this type comes from an AST file.
void setFromAST(bool V = true) const {
  TypeBits.FromAST = V;
}

1815protected:
friend class ASTContext;

Type(TypeClass tc, QualType canon, TypeDependence Dependence)
    : ExtQualsTypeCommonBase(this,
                             canon.isNull() ? QualType(this_(), 0) : canon) {
  static_assert(sizeof(*this) <= 8 + sizeof(ExtQualsTypeCommonBase),
                "changing bitfields changed sizeof(Type)!");
  static_assert(alignof(decltype(*this)) % sizeof(void *) == 0,
                "Insufficient alignment!");
  TypeBits.TC = tc;
  TypeBits.Dependence = static_cast<unsigned>(Dependence);
  TypeBits.CacheValid = false;
  TypeBits.CachedLocalOrUnnamed = false;
  TypeBits.CachedLinkage = NoLinkage;
  TypeBits.FromAST = false;
}

// silence VC++ warning C4355: 'this' : used in base member initializer list
Type *this_() { return this; }

void setDependence(TypeDependence D) {
  TypeBits.Dependence = static_cast<unsigned>(D);
}

void addDependence(TypeDependence D) { setDependence(getDependence() | D); }

1842public:
friend class ASTReader;
friend class ASTWriter;
template <class T> friend class serialization::AbstractTypeReader;
template <class T> friend class serialization::AbstractTypeWriter;

Type(const Type &) = delete;
Type(Type &&) = delete;
Type &operator=(const Type &) = delete;
Type &operator=(Type &&) = delete;

TypeClass getTypeClass() const { return static_cast<TypeClass>(TypeBits.TC); }

/// Whether this type comes from an AST file.
bool isFromAST() const { return TypeBits.FromAST; }

/// Whether this type is or contains an unexpanded parameter
/// pack, used to support C++0x variadic templates.
///
/// A type that contains a parameter pack shall be expanded by the
/// ellipsis operator at some point. For example, the typedef in the
/// following example contains an unexpanded parameter pack 'T':
///
/// \code
/// template<typename ...T>
/// struct X {
///   typedef T* pointer_types; // ill-formed; T is a parameter pack.
/// };
/// \endcode
///
/// Note that this routine does not specify which
bool containsUnexpandedParameterPack() const {
  return getDependence() & TypeDependence::UnexpandedPack;
}

/// Determines if this type would be canonical if it had no further
/// qualification.
bool isCanonicalUnqualified() const {
  return CanonicalType == QualType(this, 0);
}

/// Pull a single level of sugar off of this locally-unqualified type.
/// Users should generally prefer SplitQualType::getSingleStepDesugaredType()
/// or QualType::getSingleStepDesugaredType(const ASTContext&).
QualType getLocallyUnqualifiedSingleStepDesugaredType() const;

/// As an extension, we classify types as one of "sized" or "sizeless";
/// every type is one or the other.  Standard types are all sized;
/// sizeless types are purely an extension.
///
/// Sizeless types contain data with no specified size, alignment,
/// or layout.
bool isSizelessType() const;
bool isSizelessBuiltinType() const;

/// Determines if this is a sizeless type supported by the
/// 'arm_sve_vector_bits' type attribute, which can be applied to a single
/// SVE vector or predicate, excluding tuple types such as svint32x4_t.
bool isVLSTBuiltinType() const;

/// Returns the representative type for the element of an SVE builtin type.
/// This is used to represent fixed-length SVE vectors created with the
/// 'arm_sve_vector_bits' type attribute as VectorType.
QualType getSveEltType(const ASTContext &Ctx) const;

/// Types are partitioned into 3 broad categories (C99 6.2.5p1):
/// object types, function types, and incomplete types.

/// Return true if this is an incomplete type.
/// A type that can describe objects, but which lacks information needed to
/// determine its size (e.g. void, or a fwd declared struct). Clients of this
/// routine will need to determine if the size is actually required.
///
/// Def If non-null, and the type refers to some kind of declaration
/// that can be completed (such as a C struct, C++ class, or Objective-C
/// class), will be set to the declaration.
bool isIncompleteType(NamedDecl **Def = nullptr) const;

/// Return true if this is an incomplete or object
/// type, in other words, not a function type.
bool isIncompleteOrObjectType() const {
  return !isFunctionType();
}

/// Determine whether this type is an object type.
bool isObjectType() const {
  // C++ [basic.types]p8:
  //   An object type is a (possibly cv-qualified) type that is not a
  //   function type, not a reference type, and not a void type.
  return !isReferenceType() && !isFunctionType() && !isVoidType();
}

/// Return true if this is a literal type
/// (C++11 [basic.types]p10)
bool isLiteralType(const ASTContext &Ctx) const;

/// Determine if this type is a structural type, per C++20 [temp.param]p7.
bool isStructuralType() const;

/// Test if this type is a standard-layout type.
/// (C++0x [basic.type]p9)
bool isStandardLayoutType() const;

/// Helper methods to distinguish type categories. All type predicates
/// operate on the canonical type, ignoring typedefs and qualifiers.

/// Returns true if the type is a builtin type.
bool isBuiltinType() const;

/// Test for a particular builtin type.
bool isSpecificBuiltinType(unsigned K) const;

/// Test for a type which does not represent an actual type-system type but
/// is instead used as a placeholder for various convenient purposes within
/// Clang.  All such types are BuiltinTypes.
bool isPlaceholderType() const;
const BuiltinType *getAsPlaceholderType() const;

/// Test for a specific placeholder type.
bool isSpecificPlaceholderType(unsigned K) const;

/// Test for a placeholder type other than Overload; see
/// BuiltinType::isNonOverloadPlaceholderType.
bool isNonOverloadPlaceholderType() const;

/// isIntegerType() does *not* include complex integers (a GCC extension).
/// isComplexIntegerType() can be used to test for complex integers.
bool isIntegerType() const;     // C99 6.2.5p17 (int, char, bool, enum)
bool isEnumeralType() const;

/// Determine whether this type is a scoped enumeration type.
bool isScopedEnumeralType() const;
bool isBooleanType() const;
bool isCharType() const;
bool isWideCharType() const;
bool isChar8Type() const;
bool isChar16Type() const;
bool isChar32Type() const;
bool isAnyCharacterType() const;
bool isIntegralType(const ASTContext &Ctx) const;

/// Determine whether this type is an integral or enumeration type.
bool isIntegralOrEnumerationType() const;

/// Determine whether this type is an integral or unscoped enumeration type.
bool isIntegralOrUnscopedEnumerationType() const;
bool isUnscopedEnumerationType() const;

/// Floating point categories.
bool isRealFloatingType() const; // C99 6.2.5p10 (float, double, long double)
/// isComplexType() does *not* include complex integers (a GCC extension).
/// isComplexIntegerType() can be used to test for complex integers.
bool isComplexType() const;      // C99 6.2.5p11 (complex)
bool isAnyComplexType() const;   // C99 6.2.5p11 (complex) + Complex Int.
bool isFloatingType() const;     // C99 6.2.5p11 (real floating + complex)
bool isHalfType() const;         // OpenCL 6.1.1.1, NEON (IEEE 754-2008 half)
bool isFloat16Type() const;      // C11 extension ISO/IEC TS 18661
bool isBFloat16Type() const;
bool isFloat128Type() const;
bool isRealType() const;         // C99 6.2.5p17 (real floating + integer)
bool isArithmeticType() const;   // C99 6.2.5p18 (integer + floating)
bool isVoidType() const;         // C99 6.2.5p19
bool isScalarType() const;       // C99 6.2.5p21 (arithmetic + pointers)
bool isAggregateType() const;
bool isFundamentalType() const;
bool isCompoundType() const;

// Type Predicates: Check to see if this type is structurally the specified
// type, ignoring typedefs and qualifiers.
bool isFunctionType() const;
bool isFunctionNoProtoType() const { return getAs<FunctionNoProtoType>(); }
bool isFunctionProtoType() const { return getAs<FunctionProtoType>(); }
bool isPointerType() const;
bool isAnyPointerType() const;   // Any C pointer or ObjC object pointer
bool isBlockPointerType() const;
bool isVoidPointerType() const;
bool isReferenceType() const;
bool isLValueReferenceType() const;
bool isRValueReferenceType() const;
bool isObjectPointerType() const;
bool isFunctionPointerType() const;
bool isFunctionReferenceType() const;
bool isMemberPointerType() const;
bool isMemberFunctionPointerType() const;
bool isMemberDataPointerType() const;
bool isArrayType() const;
bool isConstantArrayType() const;
bool isIncompleteArrayType() const;
bool isVariableArrayType() const;
bool isDependentSizedArrayType() const;
bool isRecordType() const;
bool isClassType() const;
bool isStructureType() const;
bool isObjCBoxableRecordType() const;
bool isInterfaceType() const;
bool isStructureOrClassType() const;
bool isUnionType() const;
bool isComplexIntegerType() const;            // GCC _Complex integer type.
bool isVectorType() const;                    // GCC vector type.
bool isExtVectorType() const;                 // Extended vector type.
bool isMatrixType() const;                    // Matrix type.
bool isConstantMatrixType() const;            // Constant matrix type.
bool isDependentAddressSpaceType() const;     // value-dependent address space qualifier
bool isObjCObjectPointerType() const;         // pointer to ObjC object
bool isObjCRetainableType() const;            // ObjC object or block pointer
bool isObjCLifetimeType() const;              // (array of)* retainable type
bool isObjCIndirectLifetimeType() const;      // (pointer to)* lifetime type
bool isObjCNSObjectType() const;              // __attribute__((NSObject))
bool isObjCIndependentClassType() const;      // __attribute__((objc_independent_class))
// FIXME: change this to 'raw' interface type, so we can used 'interface' type
// for the common case.
bool isObjCObjectType() const;                // NSString or typeof(*(id)0)
bool isObjCQualifiedInterfaceType() const;    // NSString<foo>
bool isObjCQualifiedIdType() const;           // id<foo>
bool isObjCQualifiedClassType() const;        // Class<foo>
bool isObjCObjectOrInterfaceType() const;
bool isObjCIdType() const;                    // id
bool isDecltypeType() const;
/// Was this type written with the special inert-in-ARC __unsafe_unretained
/// qualifier?
///
/// This approximates the answer to the following question: if this
/// translation unit were compiled in ARC, would this type be qualified
/// with __unsafe_unretained?
bool isObjCInertUnsafeUnretainedType() const {
  return hasAttr(attr::ObjCInertUnsafeUnretained);
}

/// Whether the type is Objective-C 'id' or a __kindof type of an
/// object type, e.g., __kindof NSView * or __kindof id
/// <NSCopying>.
///
/// \param bound Will be set to the bound on non-id subtype types,
/// which will be (possibly specialized) Objective-C class type, or
/// null for 'id.
bool isObjCIdOrObjectKindOfType(const ASTContext &ctx,
                                const ObjCObjectType *&bound) const;

bool isObjCClassType() const;                 // Class

/// Whether the type is Objective-C 'Class' or a __kindof type of an
/// Class type, e.g., __kindof Class <NSCopying>.
///
/// Unlike \c isObjCIdOrObjectKindOfType, there is no relevant bound
/// here because Objective-C's type system cannot express "a class
/// object for a subclass of NSFoo".
bool isObjCClassOrClassKindOfType() const;

bool isBlockCompatibleObjCPointerType(ASTContext &ctx) const;
bool isObjCSelType() const;                 // Class
bool isObjCBuiltinType() const;               // 'id' or 'Class'
bool isObjCARCBridgableType() const;
bool isCARCBridgableType() const;
bool isTemplateTypeParmType() const;          // C++ template type parameter
bool isNullPtrType() const;                   // C++11 std::nullptr_t
bool isNothrowT() const;                      // C++   std::nothrow_t
bool isAlignValT() const;                     // C++17 std::align_val_t
bool isStdByteType() const;                   // C++17 std::byte
bool isAtomicType() const;                    // C11 _Atomic()
bool isUndeducedAutoType() const;             // C++11 auto or
                                              // C++14 decltype(auto)
bool isTypedefNameType() const;               // typedef or alias template

2105#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
bool is##Id##Type() const;
2107#include "clang/Basic/OpenCLImageTypes.def"

bool isImageType() const;                     // Any OpenCL image type

bool isSamplerT() const;                      // OpenCL sampler_t
bool isEventT() const;                        // OpenCL event_t
bool isClkEventT() const;                     // OpenCL clk_event_t
bool isQueueT() const;                        // OpenCL queue_t
bool isReserveIDT() const;                    // OpenCL reserve_id_t

2117#define EXT_OPAQUE_TYPE(ExtType, Id, Ext) \
bool is##Id##Type() const;
2119#include "clang/Basic/OpenCLExtensionTypes.def"
// Type defined in cl_intel_device_side_avc_motion_estimation OpenCL extension
bool isOCLIntelSubgroupAVCType() const;
bool isOCLExtOpaqueType() const;              // Any OpenCL extension type

bool isPipeType() const;                      // OpenCL pipe type
bool isExtIntType() const;                    // Extended Int Type
bool isOpenCLSpecificType() const;            // Any OpenCL specific type

/// Determines if this type, which must satisfy
/// isObjCLifetimeType(), is implicitly __unsafe_unretained rather
/// than implicitly __strong.
bool isObjCARCImplicitlyUnretainedType() const;

/// Check if the type is the CUDA device builtin surface type.
bool isCUDADeviceBuiltinSurfaceType() const;
/// Check if the type is the CUDA device builtin texture type.
bool isCUDADeviceBuiltinTextureType() const;

/// Return the implicit lifetime for this type, which must not be dependent.
Qualifiers::ObjCLifetime getObjCARCImplicitLifetime() const;

enum ScalarTypeKind {
  STK_CPointer,
  STK_BlockPointer,
  STK_ObjCObjectPointer,
  STK_MemberPointer,
  STK_Bool,
  STK_Integral,
  STK_Floating,
  STK_IntegralComplex,
  STK_FloatingComplex,
  STK_FixedPoint
};

/// Given that this is a scalar type, classify it.
ScalarTypeKind getScalarTypeKind() const;

TypeDependence getDependence() const {
  return static_cast<TypeDependence>(TypeBits.Dependence);
}

/// Whether this type is an error type.
bool containsErrors() const {
  return getDependence() & TypeDependence::Error;
}

/// Whether this type is a dependent type, meaning that its definition
/// somehow depends on a template parameter (C++ [temp.dep.type]).
bool isDependentType() const {
  return getDependence() & TypeDependence::Dependent;
}

/// Determine whether this type is an instantiation-dependent type,
/// meaning that the type involves a template parameter (even if the
/// definition does not actually depend on the type substituted for that
/// template parameter).
bool isInstantiationDependentType() const {
  return getDependence() & TypeDependence::Instantiation;
}

/// Determine whether this type is an undeduced type, meaning that
/// it somehow involves a C++11 'auto' type or similar which has not yet been
/// deduced.
bool isUndeducedType() const;

/// Whether this type is a variably-modified type (C99 6.7.5).
bool isVariablyModifiedType() const {
  return getDependence() & TypeDependence::VariablyModified;
}

/// Whether this type involves a variable-length array type
/// with a definite size.
bool hasSizedVLAType() const;

/// Whether this type is or contains a local or unnamed type.
bool hasUnnamedOrLocalType() const;

bool isOverloadableType() const;

/// Determine wither this type is a C++ elaborated-type-specifier.
bool isElaboratedTypeSpecifier() const;

bool canDecayToPointerType() const;

/// Whether this type is represented natively as a pointer.  This includes
/// pointers, references, block pointers, and Objective-C interface,
/// qualified id, and qualified interface types, as well as nullptr_t.
bool hasPointerRepresentation() const;

/// Whether this type can represent an objective pointer type for the
/// purpose of GC'ability
bool hasObjCPointerRepresentation() const;

/// Determine whether this type has an integer representation
/// of some sort, e.g., it is an integer type or a vector.
bool hasIntegerRepresentation() const;

/// Determine whether this type has an signed integer representation
/// of some sort, e.g., it is an signed integer type or a vector.
bool hasSignedIntegerRepresentation() const;

/// Determine whether this type has an unsigned integer representation
/// of some sort, e.g., it is an unsigned integer type or a vector.
bool hasUnsignedIntegerRepresentation() const;

/// Determine whether this type has a floating-point representation
/// of some sort, e.g., it is a floating-point type or a vector thereof.
bool hasFloatingRepresentation() const;

// Type Checking Functions: Check to see if this type is structurally the
// specified type, ignoring typedefs and qualifiers, and return a pointer to
// the best type we can.
const RecordType *getAsStructureType() const;
/// NOTE: getAs*ArrayType are methods on ASTContext.
const RecordType *getAsUnionType() const;
const ComplexType *getAsComplexIntegerType() const; // GCC complex int type.
const ObjCObjectType *getAsObjCInterfaceType() const;

// The following is a convenience method that returns an ObjCObjectPointerType
// for object declared using an interface.
const ObjCObjectPointerType *getAsObjCInterfacePointerType() const;
const ObjCObjectPointerType *getAsObjCQualifiedIdType() const;
const ObjCObjectPointerType *getAsObjCQualifiedClassType() const;
const ObjCObjectType *getAsObjCQualifiedInterfaceType() const;

/// Retrieves the CXXRecordDecl that this type refers to, either
/// because the type is a RecordType or because it is the injected-class-name
/// type of a class template or class template partial specialization.
CXXRecordDecl *getAsCXXRecordDecl() const;

/// Retrieves the RecordDecl this type refers to.
RecordDecl *getAsRecordDecl() const;

/// Retrieves the TagDecl that this type refers to, either
/// because the type is a TagType or because it is the injected-class-name
/// type of a class template or class template partial specialization.
TagDecl *getAsTagDecl() const;

/// If this is a pointer or reference to a RecordType, return the
/// CXXRecordDecl that the type refers to.
///
/// If this is not a pointer or reference, or the type being pointed to does
/// not refer to a CXXRecordDecl, returns NULL.
const CXXRecordDecl *getPointeeCXXRecordDecl() const;

/// Get the DeducedType whose type will be deduced for a variable with
/// an initializer of this type. This looks through declarators like pointer
/// types, but not through decltype or typedefs.
DeducedType *getContainedDeducedType() const;

/// Get the AutoType whose type will be deduced for a variable with
/// an initializer of this type. This looks through declarators like pointer
/// types, but not through decltype or typedefs.
AutoType *getContainedAutoType() const {
  return dyn_cast_or_null<AutoType>(getContainedDeducedType());
}

/// Determine whether this type was written with a leading 'auto'
/// corresponding to a trailing return type (possibly for a nested
/// function type within a pointer to function type or similar).
bool hasAutoForTrailingReturnType() const;

/// Member-template getAs<specific type>'.  Look through sugar for
/// an instance of \<specific type>.   This scheme will eventually
/// replace the specific getAsXXXX methods above.
///
/// There are some specializations of this member template listed
/// immediately following this class.
template <typename T> const T *getAs() const;

/// Member-template getAsAdjusted<specific type>. Look through specific kinds
/// of sugar (parens, attributes, etc) for an instance of \<specific type>.
/// This is used when you need to walk over sugar nodes that represent some
/// kind of type adjustment from a type that was written as a \<specific type>
/// to another type that is still canonically a \<specific type>.
template <typename T> const T *getAsAdjusted() const;

/// A variant of getAs<> for array types which silently discards
/// qualifiers from the outermost type.
const ArrayType *getAsArrayTypeUnsafe() const;

/// Member-template castAs<specific type>.  Look through sugar for
/// the underlying instance of \<specific type>.
///
/// This method has the same relationship to getAs<T> as cast<T> has
/// to dyn_cast<T>; which is to say, the underlying type *must*
/// have the intended type, and this method will never return null.
template <typename T> const T *castAs() const;

/// A variant of castAs<> for array type which silently discards
/// qualifiers from the outermost type.
const ArrayType *castAsArrayTypeUnsafe() const;

/// Determine whether this type had the specified attribute applied to it
/// (looking through top-level type sugar).
bool hasAttr(attr::Kind AK) const;

/// Get the base element type of this type, potentially discarding type
/// qualifiers.  This should never be used when type qualifiers
/// are meaningful.
const Type *getBaseElementTypeUnsafe() const;

/// If this is an array type, return the element type of the array,
/// potentially with type qualifiers missing.
/// This should never be used when type qualifiers are meaningful.
const Type *getArrayElementTypeNoTypeQual() const;

/// If this is a pointer type, return the pointee type.
/// If this is an array type, return the array element type.
/// This should never be used when type qualifiers are meaningful.
const Type *getPointeeOrArrayElementType() const;

/// If this is a pointer, ObjC object pointer, or block
/// pointer, this returns the respective pointee.
QualType getPointeeType() const;

/// Return the specified type with any "sugar" removed from the type,
/// removing any typedefs, typeofs, etc., as well as any qualifiers.
const Type *getUnqualifiedDesugaredType() const;

/// More type predicates useful for type checking/promotion
bool isPromotableIntegerType() const; // C99 6.3.1.1p2

/// Return true if this is an integer type that is
/// signed, according to C99 6.2.5p4 [char, signed char, short, int, long..],
/// or an enum decl which has a signed representation.
bool isSignedIntegerType() const;

/// Return true if this is an integer type that is
/// unsigned, according to C99 6.2.5p6 [which returns true for _Bool],
/// or an enum decl which has an unsigned representation.
bool isUnsignedIntegerType() const;

/// Determines whether this is an integer type that is signed or an
/// enumeration types whose underlying type is a signed integer type.
bool isSignedIntegerOrEnumerationType() const;

/// Determines whether this is an integer type that is unsigned or an
/// enumeration types whose underlying type is a unsigned integer type.
bool isUnsignedIntegerOrEnumerationType() const;

/// Return true if this is a fixed point type according to
/// ISO/IEC JTC1 SC22 WG14 N1169.
bool isFixedPointType() const;

/// Return true if this is a fixed point or integer type.
bool isFixedPointOrIntegerType() const;

/// Return true if this is a saturated fixed point type according to
/// ISO/IEC JTC1 SC22 WG14 N1169. This type can be signed or unsigned.
bool isSaturatedFixedPointType() const;

/// Return true if this is a saturated fixed point type according to
/// ISO/IEC JTC1 SC22 WG14 N1169. This type can be signed or unsigned.
bool isUnsaturatedFixedPointType() const;

/// Return true if this is a fixed point type that is signed according
/// to ISO/IEC JTC1 SC22 WG14 N1169. This type can also be saturated.
bool isSignedFixedPointType() const;

/// Return true if this is a fixed point type that is unsigned according
/// to ISO/IEC JTC1 SC22 WG14 N1169. This type can also be saturated.
bool isUnsignedFixedPointType() const;

/// Return true if this is not a variable sized type,
/// according to the rules of C99 6.7.5p3.  It is not legal to call this on
/// incomplete types.
bool isConstantSizeType() const;

/// Returns true if this type can be represented by some
/// set of type specifiers.
bool isSpecifierType() const;

/// Determine the linkage of this type.
Linkage getLinkage() const;

/// Determine the visibility of this type.
Visibility getVisibility() const {
  return getLinkageAndVisibility().getVisibility();
}

/// Return true if the visibility was explicitly set is the code.
bool isVisibilityExplicit() const {
  return getLinkageAndVisibility().isVisibilityExplicit();
}

/// Determine the linkage and visibility of this type.
LinkageInfo getLinkageAndVisibility() const;

/// True if the computed linkage is valid. Used for consistency
/// checking. Should always return true.
bool isLinkageValid() const;

/// Determine the nullability of the given type.
///
/// Note that nullability is only captured as sugar within the type
/// system, not as part of the canonical type, so nullability will
/// be lost by canonicalization and desugaring.
Optional<NullabilityKind> getNullability(const ASTContext &context) const;

/// Determine whether the given type can have a nullability
/// specifier applied to it, i.e., if it is any kind of pointer type.
///
/// \param ResultIfUnknown The value to return if we don't yet know whether
///        this type can have nullability because it is dependent.
bool canHaveNullability(bool ResultIfUnknown = true) const;

/// Retrieve the set of substitutions required when accessing a member
/// of the Objective-C receiver type that is declared in the given context.
///
/// \c *this is the type of the object we're operating on, e.g., the
/// receiver for a message send or the base of a property access, and is
/// expected to be of some object or object pointer type.
///
/// \param dc The declaration context for which we are building up a
/// substitution mapping, which should be an Objective-C class, extension,
/// category, or method within.
///
/// \returns an array of type arguments that can be substituted for
/// the type parameters of the given declaration context in any type described
/// within that context, or an empty optional to indicate that no
/// substitution is required.
Optional<ArrayRef<QualType>>
getObjCSubstitutions(const DeclContext *dc) const;

/// Determines if this is an ObjC interface type that may accept type
/// parameters.
bool acceptsObjCTypeParams() const;

const char *getTypeClassName() const;

QualType getCanonicalTypeInternal() const {
  return CanonicalType;
}

CanQualType getCanonicalTypeUnqualified() const; // in CanonicalType.h
void dump() const;
void dump(llvm::raw_ostream &OS, const ASTContext &Context) const;
2458};

2460/// This will check for a TypedefType by removing any existing sugar
2461/// until it reaches a TypedefType or a non-sugared type.
2462template <> const TypedefType *Type::getAs() const;

2464/// This will check for a TemplateSpecializationType by removing any
2465/// existing sugar until it reaches a TemplateSpecializationType or a
2466/// non-sugared type.
2467template <> const TemplateSpecializationType *Type::getAs() const;

2469/// This will check for an AttributedType by removing any existing sugar
2470/// until it reaches an AttributedType or a non-sugared type.
2471template <> const AttributedType *Type::getAs() const;

2473// We can do canonical leaf types faster, because we don't have to
2474// worry about preserving child type decoration.
2475#define TYPE(Class, Base)
2476#define LEAF_TYPE(Class) \
2477template <> inline const Class##Type *Type::getAs() const { \
return dyn_cast<Class##Type>(CanonicalType); \
2479} \
2480template <> inline const Class##Type *Type::castAs() const { \
return cast<Class##Type>(CanonicalType); \
2482}
2483#include "clang/AST/TypeNodes.inc"

2485/// This class is used for builtin types like 'int'.  Builtin
2486/// types are always canonical and have a literal name field.
2487class BuiltinType : public Type {
2488public:
enum Kind {
2490// OpenCL image types
2491#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) Id,
2492#include "clang/Basic/OpenCLImageTypes.def"
2493// OpenCL extension types
2494#define EXT_OPAQUE_TYPE(ExtType, Id, Ext) Id,
2495#include "clang/Basic/OpenCLExtensionTypes.def"
2496// SVE Types
2497#define SVE_TYPE(Name, Id, SingletonId) Id,
2498#include "clang/Basic/AArch64SVEACLETypes.def"
2499// PPC MMA Types
2500#define PPC_VECTOR_TYPE(Name, Id, Size) Id,
2501#include "clang/Basic/PPCTypes.def"
2502// RVV Types
2503#define RVV_TYPE(Name, Id, SingletonId) Id,
2504#include "clang/Basic/RISCVVTypes.def"
2505// All other builtin types
2506#define BUILTIN_TYPE(Id, SingletonId) Id,
2507#define LAST_BUILTIN_TYPE(Id) LastKind = Id
2508#include "clang/AST/BuiltinTypes.def"
};

2511private:
friend class ASTContext; // ASTContext creates these.

BuiltinType(Kind K)
    : Type(Builtin, QualType(),
           K == Dependent ? TypeDependence::DependentInstantiation
                          : TypeDependence::None) {
  BuiltinTypeBits.Kind = K;
}

2521public:
Kind getKind() const { return static_cast<Kind>(BuiltinTypeBits.Kind); }
StringRef getName(const PrintingPolicy &Policy) const;

const char *getNameAsCString(const PrintingPolicy &Policy) const {
  // The StringRef is null-terminated.
  StringRef str = getName(Policy);
  assert(!str.empty() && str.data()[str.size()] == '\0')((void)0);
  return str.data();
}

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

bool isInteger() const {
  return getKind() >= Bool && getKind() <= Int128;
}

bool isSignedInteger() const {
  return getKind() >= Char_S && getKind() <= Int128;
}

bool isUnsignedInteger() const {
  return getKind() >= Bool && getKind() <= UInt128;
}

bool isFloatingPoint() const {
  return getKind() >= Half && getKind() <= Float128;
}

/// Determines whether the given kind corresponds to a placeholder type.
static bool isPlaceholderTypeKind(Kind K) {
  return K >= Overload;
}

/// Determines whether this type is a placeholder type, i.e. a type
/// which cannot appear in arbitrary positions in a fully-formed
/// expression.
bool isPlaceholderType() const {
  return isPlaceholderTypeKind(getKind());
}

/// Determines whether this type is a placeholder type other than
/// Overload.  Most placeholder types require only syntactic
/// information about their context in order to be resolved (e.g.
/// whether it is a call expression), which means they can (and
/// should) be resolved in an earlier "phase" of analysis.
/// Overload expressions sometimes pick up further information
/// from their context, like whether the context expects a
/// specific function-pointer type, and so frequently need
/// special treatment.
bool isNonOverloadPlaceholderType() const {
  return getKind() > Overload;
}

static bool classof(const Type *T) { return T->getTypeClass() == Builtin; }
2577};

2579/// Complex values, per C99 6.2.5p11.  This supports the C99 complex
2580/// types (_Complex float etc) as well as the GCC integer complex extensions.
2581class ComplexType : public Type, public llvm::FoldingSetNode {
friend class ASTContext; // ASTContext creates these.

QualType ElementType;

ComplexType(QualType Element, QualType CanonicalPtr)
    : Type(Complex, CanonicalPtr, Element->getDependence()),
      ElementType(Element) {}

2590public:
QualType getElementType() const { return ElementType; }

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, getElementType());
}

static void Profile(llvm::FoldingSetNodeID &ID, QualType Element) {
  ID.AddPointer(Element.getAsOpaquePtr());
}

static bool classof(const Type *T) { return T->getTypeClass() == Complex; }
2605};

2607/// Sugar for parentheses used when specifying types.
2608class ParenType : public Type, public llvm::FoldingSetNode {
friend class ASTContext; // ASTContext creates these.

QualType Inner;

ParenType(QualType InnerType, QualType CanonType)
    : Type(Paren, CanonType, InnerType->getDependence()), Inner(InnerType) {}

2616public:
QualType getInnerType() const { return Inner; }

bool isSugared() const { return true; }
QualType desugar() const { return getInnerType(); }

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, getInnerType());
}

static void Profile(llvm::FoldingSetNodeID &ID, QualType Inner) {
  Inner.Profile(ID);
}

static bool classof(const Type *T) { return T->getTypeClass() == Paren; }
2631};

2633/// PointerType - C99 6.7.5.1 - Pointer Declarators.
2634class PointerType : public Type, public llvm::FoldingSetNode {
friend class ASTContext; // ASTContext creates these.

QualType PointeeType;

PointerType(QualType Pointee, QualType CanonicalPtr)
    : Type(Pointer, CanonicalPtr, Pointee->getDependence()),
      PointeeType(Pointee) {}

2643public:
QualType getPointeeType() const { return PointeeType; }

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, getPointeeType());
}

static void Profile(llvm::FoldingSetNodeID &ID, QualType Pointee) {
  ID.AddPointer(Pointee.getAsOpaquePtr());
}

static bool classof(const Type *T) { return T->getTypeClass() == Pointer; }
2658};

2660/// Represents a type which was implicitly adjusted by the semantic
2661/// engine for arbitrary reasons.  For example, array and function types can
2662/// decay, and function types can have their calling conventions adjusted.
2663class AdjustedType : public Type, public llvm::FoldingSetNode {
QualType OriginalTy;
QualType AdjustedTy;

2667protected:
friend class ASTContext; // ASTContext creates these.

AdjustedType(TypeClass TC, QualType OriginalTy, QualType AdjustedTy,
             QualType CanonicalPtr)
    : Type(TC, CanonicalPtr, OriginalTy->getDependence()),
      OriginalTy(OriginalTy), AdjustedTy(AdjustedTy) {}

2675public:
QualType getOriginalType() const { return OriginalTy; }
QualType getAdjustedType() const { return AdjustedTy; }

bool isSugared() const { return true; }
QualType desugar() const { return AdjustedTy; }

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, OriginalTy, AdjustedTy);
}

static void Profile(llvm::FoldingSetNodeID &ID, QualType Orig, QualType New) {
  ID.AddPointer(Orig.getAsOpaquePtr());
  ID.AddPointer(New.getAsOpaquePtr());
}

static bool classof(const Type *T) {
  return T->getTypeClass() == Adjusted || T->getTypeClass() == Decayed;
}
2694};

2696/// Represents a pointer type decayed from an array or function type.
2697class DecayedType : public AdjustedType {
friend class ASTContext; // ASTContext creates these.

inline
DecayedType(QualType OriginalType, QualType Decayed, QualType Canonical);

2703public:
QualType getDecayedType() const { return getAdjustedType(); }

inline QualType getPointeeType() const;

static bool classof(const Type *T) { return T->getTypeClass() == Decayed; }
2709};

2711/// Pointer to a block type.
2712/// This type is to represent types syntactically represented as
2713/// "void (^)(int)", etc. Pointee is required to always be a function type.
2714class BlockPointerType : public Type, public llvm::FoldingSetNode {
friend class ASTContext; // ASTContext creates these.

// Block is some kind of pointer type
QualType PointeeType;

BlockPointerType(QualType Pointee, QualType CanonicalCls)
    : Type(BlockPointer, CanonicalCls, Pointee->getDependence()),
      PointeeType(Pointee) {}

2724public:
// Get the pointee type. Pointee is required to always be a function type.
QualType getPointeeType() const { return PointeeType; }

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

void Profile(llvm::FoldingSetNodeID &ID) {
    Profile(ID, getPointeeType());
}

static void Profile(llvm::FoldingSetNodeID &ID, QualType Pointee) {
    ID.AddPointer(Pointee.getAsOpaquePtr());
}

static bool classof(const Type *T) {
  return T->getTypeClass() == BlockPointer;
}
2742};

2744/// Base for LValueReferenceType and RValueReferenceType
2745class ReferenceType : public Type, public llvm::FoldingSetNode {
QualType PointeeType;

2748protected:
ReferenceType(TypeClass tc, QualType Referencee, QualType CanonicalRef,
              bool SpelledAsLValue)
    : Type(tc, CanonicalRef, Referencee->getDependence()),
      PointeeType(Referencee) {
  ReferenceTypeBits.SpelledAsLValue = SpelledAsLValue;
  ReferenceTypeBits.InnerRef = Referencee->isReferenceType();
}

2757public:
bool isSpelledAsLValue() const { return ReferenceTypeBits.SpelledAsLValue; }
bool isInnerRef() const { return ReferenceTypeBits.InnerRef; }

QualType getPointeeTypeAsWritten() const { return PointeeType; }

QualType getPointeeType() const {
  // FIXME: this might strip inner qualifiers; okay?
  const ReferenceType *T = this;
  while (T->isInnerRef())
    T = T->PointeeType->castAs<ReferenceType>();
  return T->PointeeType;
}

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, PointeeType, isSpelledAsLValue());
}

static void Profile(llvm::FoldingSetNodeID &ID,
                    QualType Referencee,
                    bool SpelledAsLValue) {
  ID.AddPointer(Referencee.getAsOpaquePtr());
  ID.AddBoolean(SpelledAsLValue);
}

static bool classof(const Type *T) {
  return T->getTypeClass() == LValueReference ||
         T->getTypeClass() == RValueReference;
}
2786};

2788/// An lvalue reference type, per C++11 [dcl.ref].
2789class LValueReferenceType : public ReferenceType {
friend class ASTContext; // ASTContext creates these

LValueReferenceType(QualType Referencee, QualType CanonicalRef,
                    bool SpelledAsLValue)
    : ReferenceType(LValueReference, Referencee, CanonicalRef,
                    SpelledAsLValue) {}

2797public:
bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

static bool classof(const Type *T) {
  return T->getTypeClass() == LValueReference;
}
2804};

2806/// An rvalue reference type, per C++11 [dcl.ref].
2807class RValueReferenceType : public ReferenceType {
friend class ASTContext; // ASTContext creates these

RValueReferenceType(QualType Referencee, QualType CanonicalRef)
     : ReferenceType(RValueReference, Referencee, CanonicalRef, false) {}

2813public:
bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

static bool classof(const Type *T) {
  return T->getTypeClass() == RValueReference;
}
2820};

2822/// A pointer to member type per C++ 8.3.3 - Pointers to members.
2823///
2824/// This includes both pointers to data members and pointer to member functions.
2825class MemberPointerType : public Type, public llvm::FoldingSetNode {
friend class ASTContext; // ASTContext creates these.

QualType PointeeType;

/// The class of which the pointee is a member. Must ultimately be a
/// RecordType, but could be a typedef or a template parameter too.
const Type *Class;

MemberPointerType(QualType Pointee, const Type *Cls, QualType CanonicalPtr)
    : Type(MemberPointer, CanonicalPtr,
           (Cls->getDependence() & ~TypeDependence::VariablyModified) |
               Pointee->getDependence()),
      PointeeType(Pointee), Class(Cls) {}

2840public:
QualType getPointeeType() const { return PointeeType; }

/// Returns true if the member type (i.e. the pointee type) is a
/// function type rather than a data-member type.
bool isMemberFunctionPointer() const {
  return PointeeType->isFunctionProtoType();
}

/// Returns true if the member type (i.e. the pointee type) is a
/// data type rather than a function type.
bool isMemberDataPointer() const {
  return !PointeeType->isFunctionProtoType();
}

const Type *getClass() const { return Class; }
CXXRecordDecl *getMostRecentCXXRecordDecl() const;

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, getPointeeType(), getClass());
}

static void Profile(llvm::FoldingSetNodeID &ID, QualType Pointee,
                    const Type *Class) {
  ID.AddPointer(Pointee.getAsOpaquePtr());
  ID.AddPointer(Class);
}

static bool classof(const Type *T) {
  return T->getTypeClass() == MemberPointer;
}
2874};

2876/// Represents an array type, per C99 6.7.5.2 - Array Declarators.
2877class ArrayType : public Type, public llvm::FoldingSetNode {
2878public:
/// Capture whether this is a normal array (e.g. int X[4])
/// an array with a static size (e.g. int X[static 4]), or an array
/// with a star size (e.g. int X[*]).
/// 'static' is only allowed on function parameters.
enum ArraySizeModifier {
  Normal, Static, Star
};

2887private:
/// The element type of the array.
QualType ElementType;

2891protected:
friend class ASTContext; // ASTContext creates these.

ArrayType(TypeClass tc, QualType et, QualType can, ArraySizeModifier sm,
          unsigned tq, const Expr *sz = nullptr);

2897public:
QualType getElementType() const { return ElementType; }

ArraySizeModifier getSizeModifier() const {
  return ArraySizeModifier(ArrayTypeBits.SizeModifier);
}

Qualifiers getIndexTypeQualifiers() const {
  return Qualifiers::fromCVRMask(getIndexTypeCVRQualifiers());
}

unsigned getIndexTypeCVRQualifiers() const {
  return ArrayTypeBits.IndexTypeQuals;
}

static bool classof(const Type *T) {
  return T->getTypeClass() == ConstantArray ||
         T->getTypeClass() == VariableArray ||
         T->getTypeClass() == IncompleteArray ||
         T->getTypeClass() == DependentSizedArray;
}
2918};

2920/// Represents the canonical version of C arrays with a specified constant size.
2921/// For example, the canonical type for 'int A[4 + 4*100]' is a
2922/// ConstantArrayType where the element type is 'int' and the size is 404.
2923class ConstantArrayType final
  : public ArrayType,
    private llvm::TrailingObjects<ConstantArrayType, const Expr *> {
friend class ASTContext; // ASTContext creates these.
friend TrailingObjects;

llvm::APInt Size; // Allows us to unique the type.

ConstantArrayType(QualType et, QualType can, const llvm::APInt &size,
                  const Expr *sz, ArraySizeModifier sm, unsigned tq)
    : ArrayType(ConstantArray, et, can, sm, tq, sz), Size(size) {
  ConstantArrayTypeBits.HasStoredSizeExpr = sz != nullptr;
  if (ConstantArrayTypeBits.HasStoredSizeExpr) {
    assert(!can.isNull() && "canonical constant array should not have size")((void)0);
    *getTrailingObjects<const Expr*>() = sz;
  }
}

unsigned numTrailingObjects(OverloadToken<const Expr*>) const {
  return ConstantArrayTypeBits.HasStoredSizeExpr;
}

2945public:
const llvm::APInt &getSize() const { return Size; }
const Expr *getSizeExpr() const {
  return ConstantArrayTypeBits.HasStoredSizeExpr
             ? *getTrailingObjects<const Expr *>()
             : nullptr;
}
bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

/// Determine the number of bits required to address a member of
// an array with the given element type and number of elements.
static unsigned getNumAddressingBits(const ASTContext &Context,
                                     QualType ElementType,
                                     const llvm::APInt &NumElements);

/// Determine the maximum number of active bits that an array's size
/// can require, which limits the maximum size of the array.
static unsigned getMaxSizeBits(const ASTContext &Context);

void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Ctx) {
  Profile(ID, Ctx, getElementType(), getSize(), getSizeExpr(),
          getSizeModifier(), getIndexTypeCVRQualifiers());
}

static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Ctx,
                    QualType ET, const llvm::APInt &ArraySize,
                    const Expr *SizeExpr, ArraySizeModifier SizeMod,
                    unsigned TypeQuals);

static bool classof(const Type *T) {
  return T->getTypeClass() == ConstantArray;
}
2978};

2980/// Represents a C array with an unspecified size.  For example 'int A[]' has
2981/// an IncompleteArrayType where the element type is 'int' and the size is
2982/// unspecified.
2983class IncompleteArrayType : public ArrayType {
friend class ASTContext; // ASTContext creates these.

IncompleteArrayType(QualType et, QualType can,
                    ArraySizeModifier sm, unsigned tq)
    : ArrayType(IncompleteArray, et, can, sm, tq) {}

2990public:
friend class StmtIteratorBase;

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

static bool classof(const Type *T) {
  return T->getTypeClass() == IncompleteArray;
}

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, getElementType(), getSizeModifier(),
          getIndexTypeCVRQualifiers());
}

static void Profile(llvm::FoldingSetNodeID &ID, QualType ET,
                    ArraySizeModifier SizeMod, unsigned TypeQuals) {
  ID.AddPointer(ET.getAsOpaquePtr());
  ID.AddInteger(SizeMod);
  ID.AddInteger(TypeQuals);
}
3011};

3013/// Represents a C array with a specified size that is not an
3014/// integer-constant-expression.  For example, 'int s[x+foo()]'.
3015/// Since the size expression is an arbitrary expression, we store it as such.
3016///
3017/// Note: VariableArrayType's aren't uniqued (since the expressions aren't) and
3018/// should not be: two lexically equivalent variable array types could mean
3019/// different things, for example, these variables do not have the same type
3020/// dynamically:
3021///
3022/// void foo(int x) {
3023///   int Y[x];
3024///   ++x;
3025///   int Z[x];
3026/// }
3027class VariableArrayType : public ArrayType {
friend class ASTContext; // ASTContext creates these.

/// An assignment-expression. VLA's are only permitted within
/// a function block.
Stmt *SizeExpr;

/// The range spanned by the left and right array brackets.
SourceRange Brackets;

VariableArrayType(QualType et, QualType can, Expr *e,
                  ArraySizeModifier sm, unsigned tq,
                  SourceRange brackets)
    : ArrayType(VariableArray, et, can, sm, tq, e),
      SizeExpr((Stmt*) e), Brackets(brackets) {}

3043public:
friend class StmtIteratorBase;

Expr *getSizeExpr() const {
  // We use C-style casts instead of cast<> here because we do not wish
  // to have a dependency of Type.h on Stmt.h/Expr.h.
  return (Expr*) SizeExpr;
}

SourceRange getBracketsRange() const { return Brackets; }
SourceLocation getLBracketLoc() const { return Brackets.getBegin(); }
SourceLocation getRBracketLoc() const { return Brackets.getEnd(); }

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

static bool classof(const Type *T) {
  return T->getTypeClass() == VariableArray;
}

void Profile(llvm::FoldingSetNodeID &ID) {
  llvm_unreachable("Cannot unique VariableArrayTypes.")__builtin_unreachable();
}
3066};

3068/// Represents an array type in C++ whose size is a value-dependent expression.
3069///
3070/// For example:
3071/// \code
3072/// template<typename T, int Size>
3073/// class array {
3074///   T data[Size];
3075/// };
3076/// \endcode
3077///
3078/// For these types, we won't actually know what the array bound is
3079/// until template instantiation occurs, at which point this will
3080/// become either a ConstantArrayType or a VariableArrayType.
3081class DependentSizedArrayType : public ArrayType {
friend class ASTContext; // ASTContext creates these.

const ASTContext &Context;

/// An assignment expression that will instantiate to the
/// size of the array.
///
/// The expression itself might be null, in which case the array
/// type will have its size deduced from an initializer.
Stmt *SizeExpr;

/// The range spanned by the left and right array brackets.
SourceRange Brackets;

DependentSizedArrayType(const ASTContext &Context, QualType et, QualType can,
                        Expr *e, ArraySizeModifier sm, unsigned tq,
                        SourceRange brackets);

3100public:
friend class StmtIteratorBase;

Expr *getSizeExpr() const {
  // We use C-style casts instead of cast<> here because we do not wish
  // to have a dependency of Type.h on Stmt.h/Expr.h.
  return (Expr*) SizeExpr;
}

SourceRange getBracketsRange() const { return Brackets; }
SourceLocation getLBracketLoc() const { return Brackets.getBegin(); }
SourceLocation getRBracketLoc() const { return Brackets.getEnd(); }

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

static bool classof(const Type *T) {
  return T->getTypeClass() == DependentSizedArray;
}

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, Context, getElementType(),
          getSizeModifier(), getIndexTypeCVRQualifiers(), getSizeExpr());
}

static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
                    QualType ET, ArraySizeModifier SizeMod,
                    unsigned TypeQuals, Expr *E);
3128};

3130/// Represents an extended address space qualifier where the input address space
3131/// value is dependent. Non-dependent address spaces are not represented with a
3132/// special Type subclass; they are stored on an ExtQuals node as part of a QualType.
3133///
3134/// For example:
3135/// \code
3136/// template<typename T, int AddrSpace>
3137/// class AddressSpace {
3138///   typedef T __attribute__((address_space(AddrSpace))) type;
3139/// }
3140/// \endcode
3141class DependentAddressSpaceType : public Type, public llvm::FoldingSetNode {
friend class ASTContext;

const ASTContext &Context;
Expr *AddrSpaceExpr;
QualType PointeeType;
SourceLocation loc;

DependentAddressSpaceType(const ASTContext &Context, QualType PointeeType,
                          QualType can, Expr *AddrSpaceExpr,
                          SourceLocation loc);

3153public:
Expr *getAddrSpaceExpr() const { return AddrSpaceExpr; }
QualType getPointeeType() const { return PointeeType; }
SourceLocation getAttributeLoc() const { return loc; }

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

static bool classof(const Type *T) {
  return T->getTypeClass() == DependentAddressSpace;
}

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, Context, getPointeeType(), getAddrSpaceExpr());
}

static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
                    QualType PointeeType, Expr *AddrSpaceExpr);
3171};

3173/// Represents an extended vector type where either the type or size is
3174/// dependent.
3175///
3176/// For example:
3177/// \code
3178/// template<typename T, int Size>
3179/// class vector {
3180///   typedef T __attribute__((ext_vector_type(Size))) type;
3181/// }
3182/// \endcode
3183class DependentSizedExtVectorType : public Type, public llvm::FoldingSetNode {
friend class ASTContext;

const ASTContext &Context;
Expr *SizeExpr;

/// The element type of the array.
QualType ElementType;

SourceLocation loc;

DependentSizedExtVectorType(const ASTContext &Context, QualType ElementType,
                            QualType can, Expr *SizeExpr, SourceLocation loc);

3197public:
Expr *getSizeExpr() const { return SizeExpr; }
QualType getElementType() const { return ElementType; }
SourceLocation getAttributeLoc() const { return loc; }

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

static bool classof(const Type *T) {
  return T->getTypeClass() == DependentSizedExtVector;
}

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, Context, getElementType(), getSizeExpr());
}

static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
                    QualType ElementType, Expr *SizeExpr);
3215};


3218/// Represents a GCC generic vector type. This type is created using
3219/// __attribute__((vector_size(n)), where "n" specifies the vector size in
3220/// bytes; or from an Altivec __vector or vector declaration.
3221/// Since the constructor takes the number of vector elements, the
3222/// client is responsible for converting the size into the number of elements.
3223class VectorType : public Type, public llvm::FoldingSetNode {
3224public:
enum VectorKind {
  /// not a target-specific vector type
  GenericVector,

  /// is AltiVec vector
  AltiVecVector,

  /// is AltiVec 'vector Pixel'
  AltiVecPixel,

  /// is AltiVec 'vector bool ...'
  AltiVecBool,

  /// is ARM Neon vector
  NeonVector,

  /// is ARM Neon polynomial vector
  NeonPolyVector,

  /// is AArch64 SVE fixed-length data vector
  SveFixedLengthDataVector,

  /// is AArch64 SVE fixed-length predicate vector
  SveFixedLengthPredicateVector
};

3251protected:
friend class ASTContext; // ASTContext creates these.

/// The element type of the vector.
QualType ElementType;

VectorType(QualType vecType, unsigned nElements, QualType canonType,
           VectorKind vecKind);

VectorType(TypeClass tc, QualType vecType, unsigned nElements,
           QualType canonType, VectorKind vecKind);

3263public:
QualType getElementType() const { return ElementType; }
unsigned getNumElements() const { return VectorTypeBits.NumElements; }

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

VectorKind getVectorKind() const {
  return VectorKind(VectorTypeBits.VecKind);
}

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, getElementType(), getNumElements(),
          getTypeClass(), getVectorKind());
}

static void Profile(llvm::FoldingSetNodeID &ID, QualType ElementType,
                    unsigned NumElements, TypeClass TypeClass,
                    VectorKind VecKind) {
  ID.AddPointer(ElementType.getAsOpaquePtr());
  ID.AddInteger(NumElements);
  ID.AddInteger(TypeClass);
  ID.AddInteger(VecKind);
}

static bool classof(const Type *T) {
  return T->getTypeClass() == Vector || T->getTypeClass() == ExtVector;
}
3291};

3293/// Represents a vector type where either the type or size is dependent.
3294////
3295/// For example:
3296/// \code
3297/// template<typename T, int Size>
3298/// class vector {
3299///   typedef T __attribute__((vector_size(Size))) type;
3300/// }
3301/// \endcode
3302class DependentVectorType : public Type, public llvm::FoldingSetNode {
friend class ASTContext;

const ASTContext &Context;
QualType ElementType;
Expr *SizeExpr;
SourceLocation Loc;

DependentVectorType(const ASTContext &Context, QualType ElementType,
                         QualType CanonType, Expr *SizeExpr,
                         SourceLocation Loc, VectorType::VectorKind vecKind);

3314public:
Expr *getSizeExpr() const { return SizeExpr; }
QualType getElementType() const { return ElementType; }
SourceLocation getAttributeLoc() const { return Loc; }
VectorType::VectorKind getVectorKind() const {
  return VectorType::VectorKind(VectorTypeBits.VecKind);
}

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

static bool classof(const Type *T) {
  return T->getTypeClass() == DependentVector;
}

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, Context, getElementType(), getSizeExpr(), getVectorKind());
}

static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
                    QualType ElementType, const Expr *SizeExpr,
                    VectorType::VectorKind VecKind);
3336};

3338/// ExtVectorType - Extended vector type. This type is created using
3339/// __attribute__((ext_vector_type(n)), where "n" is the number of elements.
3340/// Unlike vector_size, ext_vector_type is only allowed on typedef's. This
3341/// class enables syntactic extensions, like Vector Components for accessing
3342/// points (as .xyzw), colors (as .rgba), and textures (modeled after OpenGL
3343/// Shading Language).
3344class ExtVectorType : public VectorType {
friend class ASTContext; // ASTContext creates these.

ExtVectorType(QualType vecType, unsigned nElements, QualType canonType)
    : VectorType(ExtVector, vecType, nElements, canonType, GenericVector) {}

3350public:
static int getPointAccessorIdx(char c) {
  switch (c) {
  default: return -1;
  case 'x': case 'r': return 0;
  case 'y': case 'g': return 1;
  case 'z': case 'b': return 2;
  case 'w': case 'a': return 3;
  }
}

static int getNumericAccessorIdx(char c) {
  switch (c) {
    default: return -1;
    case '0': return 0;
    case '1': return 1;
    case '2': return 2;
    case '3': return 3;
    case '4': return 4;
    case '5': return 5;
    case '6': return 6;
    case '7': return 7;
    case '8': return 8;
    case '9': return 9;
    case 'A':
    case 'a': return 10;
    case 'B':
    case 'b': return 11;
    case 'C':
    case 'c': return 12;
    case 'D':
    case 'd': return 13;
    case 'E':
    case 'e': return 14;
    case 'F':
    case 'f': return 15;
  }
}

static int getAccessorIdx(char c, bool isNumericAccessor) {
  if (isNumericAccessor)
    return getNumericAccessorIdx(c);
  else
    return getPointAccessorIdx(c);
}

bool isAccessorWithinNumElements(char c, bool isNumericAccessor) const {
  if (int idx = getAccessorIdx(c, isNumericAccessor)+1)
    return unsigned(idx-1) < getNumElements();
  return false;
}

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

static bool classof(const Type *T) {
  return T->getTypeClass() == ExtVector;
}
3408};

3410/// Represents a matrix type, as defined in the Matrix Types clang extensions.
3411/// __attribute__((matrix_type(rows, columns))), where "rows" specifies
3412/// number of rows and "columns" specifies the number of columns.
3413class MatrixType : public Type, public llvm::FoldingSetNode {
3414protected:
friend class ASTContext;

/// The element type of the matrix.
QualType ElementType;

MatrixType(QualType ElementTy, QualType CanonElementTy);

MatrixType(TypeClass TypeClass, QualType ElementTy, QualType CanonElementTy,
           const Expr *RowExpr = nullptr, const Expr *ColumnExpr = nullptr);

3425public:
/// Returns type of the elements being stored in the matrix
QualType getElementType() const { return ElementType; }

/// Valid elements types are the following:
/// * an integer type (as in C2x 6.2.5p19), but excluding enumerated types
///   and _Bool
/// * the standard floating types float or double
/// * a half-precision floating point type, if one is supported on the target
static bool isValidElementType(QualType T) {
  return T->isDependentType() ||
         (T->isRealType() && !T->isBooleanType() && !T->isEnumeralType());
}

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

static bool classof(const Type *T) {
  return T->getTypeClass() == ConstantMatrix ||
         T->getTypeClass() == DependentSizedMatrix;
}
3446};

3448/// Represents a concrete matrix type with constant number of rows and columns
3449class ConstantMatrixType final : public MatrixType {
3450protected:
friend class ASTContext;

/// The element type of the matrix.
// FIXME: Appears to be unused? There is also MatrixType::ElementType...
QualType ElementType;

/// Number of rows and columns.
unsigned NumRows;
unsigned NumColumns;

static constexpr unsigned MaxElementsPerDimension = (1 << 20) - 1;

ConstantMatrixType(QualType MatrixElementType, unsigned NRows,
                   unsigned NColumns, QualType CanonElementType);

ConstantMatrixType(TypeClass typeClass, QualType MatrixType, unsigned NRows,
                   unsigned NColumns, QualType CanonElementType);

3469public:
/// Returns the number of rows in the matrix.
unsigned getNumRows() const { return NumRows; }

/// Returns the number of columns in the matrix.
unsigned getNumColumns() const { return NumColumns; }

/// Returns the number of elements required to embed the matrix into a vector.
unsigned getNumElementsFlattened() const {
  return getNumRows() * getNumColumns();
}

/// Returns true if \p NumElements is a valid matrix dimension.
static constexpr bool isDimensionValid(size_t NumElements) {
  return NumElements > 0 && NumElements <= MaxElementsPerDimension;
}

/// Returns the maximum number of elements per dimension.
static constexpr unsigned getMaxElementsPerDimension() {
  return MaxElementsPerDimension;
}

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, getElementType(), getNumRows(), getNumColumns(),
          getTypeClass());
}

static void Profile(llvm::FoldingSetNodeID &ID, QualType ElementType,
                    unsigned NumRows, unsigned NumColumns,
                    TypeClass TypeClass) {
  ID.AddPointer(ElementType.getAsOpaquePtr());
  ID.AddInteger(NumRows);
  ID.AddInteger(NumColumns);
  ID.AddInteger(TypeClass);
}

static bool classof(const Type *T) {
  return T->getTypeClass() == ConstantMatrix;
}
3508};

3510/// Represents a matrix type where the type and the number of rows and columns
3511/// is dependent on a template.
3512class DependentSizedMatrixType final : public MatrixType {
friend class ASTContext;

const ASTContext &Context;
Expr *RowExpr;
Expr *ColumnExpr;

SourceLocation loc;

DependentSizedMatrixType(const ASTContext &Context, QualType ElementType,
                         QualType CanonicalType, Expr *RowExpr,
                         Expr *ColumnExpr, SourceLocation loc);

3525public:
QualType getElementType() const { return ElementType; }
Expr *getRowExpr() const { return RowExpr; }
Expr *getColumnExpr() const { return ColumnExpr; }
SourceLocation getAttributeLoc() const { return loc; }

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

static bool classof(const Type *T) {
  return T->getTypeClass() == DependentSizedMatrix;
}

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, Context, getElementType(), getRowExpr(), getColumnExpr());
}

static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
                    QualType ElementType, Expr *RowExpr, Expr *ColumnExpr);
3544};

3546/// FunctionType - C99 6.7.5.3 - Function Declarators.  This is the common base
3547/// class of FunctionNoProtoType and FunctionProtoType.
3548class FunctionType : public Type {
// The type returned by the function.
QualType ResultType;

3552public:
/// Interesting information about a specific parameter that can't simply
/// be reflected in parameter's type. This is only used by FunctionProtoType
/// but is in FunctionType to make this class available during the
/// specification of the bases of FunctionProtoType.
///
/// It makes sense to model language features this way when there's some
/// sort of parameter-specific override (such as an attribute) that
/// affects how the function is called.  For example, the ARC ns_consumed
/// attribute changes whether a parameter is passed at +0 (the default)
/// or +1 (ns_consumed).  This must be reflected in the function type,
/// but isn't really a change to the parameter type.
///
/// One serious disadvantage of modelling language features this way is
/// that they generally do not work with language features that attempt
/// to destructure types.  For example, template argument deduction will
/// not be able to match a parameter declared as
///   T (*)(U)
/// against an argument of type
///   void (*)(__attribute__((ns_consumed)) id)
/// because the substitution of T=void, U=id into the former will
/// not produce the latter.
class ExtParameterInfo {
  enum {
    ABIMask = 0x0F,
    IsConsumed = 0x10,
    HasPassObjSize = 0x20,
    IsNoEscape = 0x40,
  };
  unsigned char Data = 0;

public:
  ExtParameterInfo() = default;

  /// Return the ABI treatment of this parameter.
  ParameterABI getABI() const { return ParameterABI(Data & ABIMask); }
  ExtParameterInfo withABI(ParameterABI kind) const {
    ExtParameterInfo copy = *this;
    copy.Data = (copy.Data & ~ABIMask) | unsigned(kind);
    return copy;
  }

  /// Is this parameter considered "consumed" by Objective-C ARC?
  /// Consumed parameters must have retainable object type.
  bool isConsumed() const { return (Data & IsConsumed); }
  ExtParameterInfo withIsConsumed(bool consumed) const {
    ExtParameterInfo copy = *this;
    if (consumed)
      copy.Data |= IsConsumed;
    else
      copy.Data &= ~IsConsumed;
    return copy;
  }

  bool hasPassObjectSize() const { return Data & HasPassObjSize; }
  ExtParameterInfo withHasPassObjectSize() const {
    ExtParameterInfo Copy = *this;
    Copy.Data |= HasPassObjSize;
    return Copy;
  }

  bool isNoEscape() const { return Data & IsNoEscape; }
  ExtParameterInfo withIsNoEscape(bool NoEscape) const {
    ExtParameterInfo Copy = *this;
    if (NoEscape)
      Copy.Data |= IsNoEscape;
    else
      Copy.Data &= ~IsNoEscape;
    return Copy;
  }

  unsigned char getOpaqueValue() const { return Data; }
  static ExtParameterInfo getFromOpaqueValue(unsigned char data) {
    ExtParameterInfo result;
    result.Data = data;
    return result;
  }

  friend bool operator==(ExtParameterInfo lhs, ExtParameterInfo rhs) {
    return lhs.Data == rhs.Data;
  }

  friend bool operator!=(ExtParameterInfo lhs, ExtParameterInfo rhs) {
    return lhs.Data != rhs.Data;
  }
};

/// A class which abstracts out some details necessary for
/// making a call.
///
/// It is not actually used directly for storing this information in
/// a FunctionType, although FunctionType does currently use the
/// same bit-pattern.
///
// If you add a field (say Foo), other than the obvious places (both,
// constructors, compile failures), what you need to update is
// * Operator==
// * getFoo
// * withFoo
// * functionType. Add Foo, getFoo.
// * ASTContext::getFooType
// * ASTContext::mergeFunctionTypes
// * FunctionNoProtoType::Profile
// * FunctionProtoType::Profile
// * TypePrinter::PrintFunctionProto
// * AST read and write
// * Codegen
class ExtInfo {
  friend class FunctionType;

  // Feel free to rearrange or add bits, but if you go over 16, you'll need to
  // adjust the Bits field below, and if you add bits, you'll need to adjust
  // Type::FunctionTypeBitfields::ExtInfo as well.

  // |  CC  |noreturn|produces|nocallersavedregs|regparm|nocfcheck|cmsenscall|
  // |0 .. 4|   5    |    6   |       7         |8 .. 10|    11   |    12    |
  //
  // regparm is either 0 (no regparm attribute) or the regparm value+1.
  enum { CallConvMask = 0x1F };
  enum { NoReturnMask = 0x20 };
  enum { ProducesResultMask = 0x40 };
  enum { NoCallerSavedRegsMask = 0x80 };
  enum {
    RegParmMask =  0x700,
    RegParmOffset = 8
  };
  enum { NoCfCheckMask = 0x800 };
  enum { CmseNSCallMask = 0x1000 };
  uint16_t Bits = CC_C;

  ExtInfo(unsigned Bits) : Bits(static_cast<uint16_t>(Bits)) {}

public:
  // Constructor with no defaults. Use this when you know that you
  // have all the elements (when reading an AST file for example).
  ExtInfo(bool noReturn, bool hasRegParm, unsigned regParm, CallingConv cc,
          bool producesResult, bool noCallerSavedRegs, bool NoCfCheck,
          bool cmseNSCall) {
    assert((!hasRegParm || regParm < 7) && "Invalid regparm value")((void)0);
    Bits = ((unsigned)cc) | (noReturn ? NoReturnMask : 0) |
           (producesResult ? ProducesResultMask : 0) |
           (noCallerSavedRegs ? NoCallerSavedRegsMask : 0) |
           (hasRegParm ? ((regParm + 1) << RegParmOffset) : 0) |
           (NoCfCheck ? NoCfCheckMask : 0) |
           (cmseNSCall ? CmseNSCallMask : 0);
  }

  // Constructor with all defaults. Use when for example creating a
  // function known to use defaults.
  ExtInfo() = default;

  // Constructor with just the calling convention, which is an important part
  // of the canonical type.
  ExtInfo(CallingConv CC) : Bits(CC) {}

  bool getNoReturn() const { return Bits & NoReturnMask; }
  bool getProducesResult() const { return Bits & ProducesResultMask; }
  bool getCmseNSCall() const { return Bits & CmseNSCallMask; }
  bool getNoCallerSavedRegs() const { return Bits & NoCallerSavedRegsMask; }
  bool getNoCfCheck() const { return Bits & NoCfCheckMask; }
  bool getHasRegParm() const { return ((Bits & RegParmMask) >> RegParmOffset) != 0; }

  unsigned getRegParm() const {
    unsigned RegParm = (Bits & RegParmMask) >> RegParmOffset;
    if (RegParm > 0)
      --RegParm;
    return RegParm;
  }

  CallingConv getCC() const { return CallingConv(Bits & CallConvMask); }

  bool operator==(ExtInfo Other) const {
    return Bits == Other.Bits;
  }
  bool operator!=(ExtInfo Other) const {
    return Bits != Other.Bits;
  }

  // Note that we don't have setters. That is by design, use
  // the following with methods instead of mutating these objects.

  ExtInfo withNoReturn(bool noReturn) const {
    if (noReturn)
      return ExtInfo(Bits | NoReturnMask);
    else
      return ExtInfo(Bits & ~NoReturnMask);
  }

  ExtInfo withProducesResult(bool producesResult) const {
    if (producesResult)
      return ExtInfo(Bits | ProducesResultMask);
    else
      return ExtInfo(Bits & ~ProducesResultMask);
  }

  ExtInfo withCmseNSCall(bool cmseNSCall) const {
    if (cmseNSCall)
      return ExtInfo(Bits | CmseNSCallMask);
    else
      return ExtInfo(Bits & ~CmseNSCallMask);
  }

  ExtInfo withNoCallerSavedRegs(bool noCallerSavedRegs) const {
    if (noCallerSavedRegs)
      return ExtInfo(Bits | NoCallerSavedRegsMask);
    else
      return ExtInfo(Bits & ~NoCallerSavedRegsMask);
  }

  ExtInfo withNoCfCheck(bool noCfCheck) const {
    if (noCfCheck)
      return ExtInfo(Bits | NoCfCheckMask);
    else
      return ExtInfo(Bits & ~NoCfCheckMask);
  }

  ExtInfo withRegParm(unsigned RegParm) const {
    assert(RegParm < 7 && "Invalid regparm value")((void)0);
    return ExtInfo((Bits & ~RegParmMask) |
                   ((RegParm + 1) << RegParmOffset));
  }

  ExtInfo withCallingConv(CallingConv cc) const {
    return ExtInfo((Bits & ~CallConvMask) | (unsigned) cc);
  }

  void Profile(llvm::FoldingSetNodeID &ID) const {
    ID.AddInteger(Bits);
  }
};

/// A simple holder for a QualType representing a type in an
/// exception specification. Unfortunately needed by FunctionProtoType
/// because TrailingObjects cannot handle repeated types.
struct ExceptionType { QualType Type; };

/// A simple holder for various uncommon bits which do not fit in
/// FunctionTypeBitfields. Aligned to alignof(void *) to maintain the
/// alignment of subsequent objects in TrailingObjects. You must update
/// hasExtraBitfields in FunctionProtoType after adding extra data here.
struct alignas(void *) FunctionTypeExtraBitfields {
  /// The number of types in the exception specification.
  /// A whole unsigned is not needed here and according to
  /// [implimits] 8 bits would be enough here.
  unsigned NumExceptionType;
};

3799protected:
FunctionType(TypeClass tc, QualType res, QualType Canonical,
             TypeDependence Dependence, ExtInfo Info)
    : Type(tc, Canonical, Dependence), ResultType(res) {
  FunctionTypeBits.ExtInfo = Info.Bits;
}

Qualifiers getFastTypeQuals() const {
  return Qualifiers::fromFastMask(FunctionTypeBits.FastTypeQuals);
}

3810public:
QualType getReturnType() const { return ResultType; }

bool getHasRegParm() const { return getExtInfo().getHasRegParm(); }
unsigned getRegParmType() const { return getExtInfo().getRegParm(); }

/// Determine whether this function type includes the GNU noreturn
/// attribute. The C++11 [[noreturn]] attribute does not affect the function
/// type.
bool getNoReturnAttr() const { return getExtInfo().getNoReturn(); }

bool getCmseNSCallAttr() const { return getExtInfo().getCmseNSCall(); }
CallingConv getCallConv() const { return getExtInfo().getCC(); }
ExtInfo getExtInfo() const { return ExtInfo(FunctionTypeBits.ExtInfo); }

static_assert((~Qualifiers::FastMask & Qualifiers::CVRMask) == 0,
              "Const, volatile and restrict are assumed to be a subset of "
              "the fast qualifiers.");

bool isConst() const { return getFastTypeQuals().hasConst(); }
bool isVolatile() const { return getFastTypeQuals().hasVolatile(); }
bool isRestrict() const { return getFastTypeQuals().hasRestrict(); }

/// Determine the type of an expression that calls a function of
/// this type.
QualType getCallResultType(const ASTContext &Context) const {
  return getReturnType().getNonLValueExprType(Context);
}

static StringRef getNameForCallConv(CallingConv CC);

static bool classof(const Type *T) {
  return T->getTypeClass() == FunctionNoProto ||
         T->getTypeClass() == FunctionProto;
}
3845};

3847/// Represents a K&R-style 'int foo()' function, which has
3848/// no information available about its arguments.
3849class FunctionNoProtoType : public FunctionType, public llvm::FoldingSetNode {
friend class ASTContext; // ASTContext creates these.

FunctionNoProtoType(QualType Result, QualType Canonical, ExtInfo Info)
    : FunctionType(FunctionNoProto, Result, Canonical,
                   Result->getDependence() &
                       ~(TypeDependence::DependentInstantiation |
                         TypeDependence::UnexpandedPack),
                   Info) {}

3859public:
// No additional state past what FunctionType provides.

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, getReturnType(), getExtInfo());
}

static void Profile(llvm::FoldingSetNodeID &ID, QualType ResultType,
                    ExtInfo Info) {
  Info.Profile(ID);
  ID.AddPointer(ResultType.getAsOpaquePtr());
}

static bool classof(const Type *T) {
  return T->getTypeClass() == FunctionNoProto;
}
3878};

3880/// Represents a prototype with parameter type info, e.g.
3881/// 'int foo(int)' or 'int foo(void)'.  'void' is represented as having no
3882/// parameters, not as having a single void parameter. Such a type can have
3883/// an exception specification, but this specification is not part of the
3884/// canonical type. FunctionProtoType has several trailing objects, some of
3885/// which optional. For more information about the trailing objects see
3886/// the first comment inside FunctionProtoType.
3887class FunctionProtoType final
  : public FunctionType,
    public llvm::FoldingSetNode,
    private llvm::TrailingObjects<
        FunctionProtoType, QualType, SourceLocation,
        FunctionType::FunctionTypeExtraBitfields, FunctionType::ExceptionType,
        Expr *, FunctionDecl *, FunctionType::ExtParameterInfo, Qualifiers> {
friend class ASTContext; // ASTContext creates these.
friend TrailingObjects;

// FunctionProtoType is followed by several trailing objects, some of
// which optional. They are in order:
//
// * An array of getNumParams() QualType holding the parameter types.
//   Always present. Note that for the vast majority of FunctionProtoType,
//   these will be the only trailing objects.
//
// * Optionally if the function is variadic, the SourceLocation of the
//   ellipsis.
//
// * Optionally if some extra data is stored in FunctionTypeExtraBitfields
//   (see FunctionTypeExtraBitfields and FunctionTypeBitfields):
//   a single FunctionTypeExtraBitfields. Present if and only if
//   hasExtraBitfields() is true.
//
// * Optionally exactly one of:
//   * an array of getNumExceptions() ExceptionType,
//   * a single Expr *,
//   * a pair of FunctionDecl *,
//   * a single FunctionDecl *
//   used to store information about the various types of exception
//   specification. See getExceptionSpecSize for the details.
//
// * Optionally an array of getNumParams() ExtParameterInfo holding
//   an ExtParameterInfo for each of the parameters. Present if and
//   only if hasExtParameterInfos() is true.
//
// * Optionally a Qualifiers object to represent extra qualifiers that can't
//   be represented by FunctionTypeBitfields.FastTypeQuals. Present if and only
//   if hasExtQualifiers() is true.
//
// The optional FunctionTypeExtraBitfields has to be before the data
// related to the exception specification since it contains the number
// of exception types.
//
// We put the ExtParameterInfos last.  If all were equal, it would make
// more sense to put these before the exception specification, because
// it's much easier to skip past them compared to the elaborate switch
// required to skip the exception specification.  However, all is not
// equal; ExtParameterInfos are used to model very uncommon features,
// and it's better not to burden the more common paths.

3939public:
/// Holds information about the various types of exception specification.
/// ExceptionSpecInfo is not stored as such in FunctionProtoType but is
/// used to group together the various bits of information about the
/// exception specification.
struct ExceptionSpecInfo {
  /// The kind of exception specification this is.
  ExceptionSpecificationType Type = EST_None;

  /// Explicitly-specified list of exception types.
  ArrayRef<QualType> Exceptions;

  /// Noexcept expression, if this is a computed noexcept specification.
  Expr *NoexceptExpr = nullptr;

  /// The function whose exception specification this is, for
  /// EST_Unevaluated and EST_Uninstantiated.
  FunctionDecl *SourceDecl = nullptr;

  /// The function template whose exception specification this is instantiated
  /// from, for EST_Uninstantiated.
  FunctionDecl *SourceTemplate = nullptr;

  ExceptionSpecInfo() = default;

  ExceptionSpecInfo(ExceptionSpecificationType EST) : Type(EST) {}
};

/// Extra information about a function prototype. ExtProtoInfo is not
/// stored as such in FunctionProtoType but is used to group together
/// the various bits of extra information about a function prototype.
struct ExtProtoInfo {
  FunctionType::ExtInfo ExtInfo;
  bool Variadic : 1;
  bool HasTrailingReturn : 1;
  Qualifiers TypeQuals;
  RefQualifierKind RefQualifier = RQ_None;
  ExceptionSpecInfo ExceptionSpec;
  const ExtParameterInfo *ExtParameterInfos = nullptr;
  SourceLocation EllipsisLoc;

  ExtProtoInfo() : Variadic(false), HasTrailingReturn(false) {}

  ExtProtoInfo(CallingConv CC)
      : ExtInfo(CC), Variadic(false), HasTrailingReturn(false) {}

  ExtProtoInfo withExceptionSpec(const ExceptionSpecInfo &ESI) {
    ExtProtoInfo Result(*this);
    Result.ExceptionSpec = ESI;
    return Result;
  }
};

3992private:
unsigned numTrailingObjects(OverloadToken<QualType>) const {
  return getNumParams();
}

unsigned numTrailingObjects(OverloadToken<SourceLocation>) const {
  return isVariadic();
}

unsigned numTrailingObjects(OverloadToken<FunctionTypeExtraBitfields>) const {
  return hasExtraBitfields();
}

unsigned numTrailingObjects(OverloadToken<ExceptionType>) const {
  return getExceptionSpecSize().NumExceptionType;
}

unsigned numTrailingObjects(OverloadToken<Expr *>) const {
  return getExceptionSpecSize().NumExprPtr;
}

unsigned numTrailingObjects(OverloadToken<FunctionDecl *>) const {
  return getExceptionSpecSize().NumFunctionDeclPtr;
}

unsigned numTrailingObjects(OverloadToken<ExtParameterInfo>) const {
  return hasExtParameterInfos() ? getNumParams() : 0;
}

/// Determine whether there are any argument types that
/// contain an unexpanded parameter pack.
static bool containsAnyUnexpandedParameterPack(const QualType *ArgArray,
                                               unsigned numArgs) {
  for (unsigned Idx = 0; Idx < numArgs; ++Idx)
    if (ArgArray[Idx]->containsUnexpandedParameterPack())
      return true;

  return false;
}

FunctionProtoType(QualType result, ArrayRef<QualType> params,
                  QualType canonical, const ExtProtoInfo &epi);

/// This struct is returned by getExceptionSpecSize and is used to
/// translate an ExceptionSpecificationType to the number and kind
/// of trailing objects related to the exception specification.
struct ExceptionSpecSizeHolder {
  unsigned NumExceptionType;
  unsigned NumExprPtr;
  unsigned NumFunctionDeclPtr;
};

/// Return the number and kind of trailing objects
/// related to the exception specification.
static ExceptionSpecSizeHolder
getExceptionSpecSize(ExceptionSpecificationType EST, unsigned NumExceptions) {
  switch (EST) {
  case EST_None:
  case EST_DynamicNone:
  case EST_MSAny:
  case EST_BasicNoexcept:
  case EST_Unparsed:
  case EST_NoThrow:
    return {0, 0, 0};

  case EST_Dynamic:
    return {NumExceptions, 0, 0};

  case EST_DependentNoexcept:
  case EST_NoexceptFalse:
  case EST_NoexceptTrue:
    return {0, 1, 0};

  case EST_Uninstantiated:
    return {0, 0, 2};

  case EST_Unevaluated:
    return {0, 0, 1};
  }
  llvm_unreachable("bad exception specification kind")__builtin_unreachable();
}

/// Return the number and kind of trailing objects
/// related to the exception specification.
ExceptionSpecSizeHolder getExceptionSpecSize() const {
  return getExceptionSpecSize(getExceptionSpecType(), getNumExceptions());
}

/// Whether the trailing FunctionTypeExtraBitfields is present.
static bool hasExtraBitfields(ExceptionSpecificationType EST) {
  // If the exception spec type is EST_Dynamic then we have > 0 exception
  // types and the exact number is stored in FunctionTypeExtraBitfields.
  return EST == EST_Dynamic;
}

/// Whether the trailing FunctionTypeExtraBitfields is present.
bool hasExtraBitfields() const {
  return hasExtraBitfields(getExceptionSpecType());
}

bool hasExtQualifiers() const {
  return FunctionTypeBits.HasExtQuals;
}

4096public:
unsigned getNumParams() const { return FunctionTypeBits.NumParams; }

QualType getParamType(unsigned i) const {
  assert(i < getNumParams() && "invalid parameter index")((void)0);
  return param_type_begin()[i];
}

ArrayRef<QualType> getParamTypes() const {
  return llvm::makeArrayRef(param_type_begin(), param_type_end());
}

ExtProtoInfo getExtProtoInfo() const {
  ExtProtoInfo EPI;
  EPI.ExtInfo = getExtInfo();
  EPI.Variadic = isVariadic();
  EPI.EllipsisLoc = getEllipsisLoc();
  EPI.HasTrailingReturn = hasTrailingReturn();
  EPI.ExceptionSpec = getExceptionSpecInfo();
  EPI.TypeQuals = getMethodQuals();
  EPI.RefQualifier = getRefQualifier();
  EPI.ExtParameterInfos = getExtParameterInfosOrNull();
  return EPI;
}

/// Get the kind of exception specification on this function.
ExceptionSpecificationType getExceptionSpecType() const {
  return static_cast<ExceptionSpecificationType>(
      FunctionTypeBits.ExceptionSpecType);
}

/// Return whether this function has any kind of exception spec.
bool hasExceptionSpec() const { return getExceptionSpecType() != EST_None; }

/// Return whether this function has a dynamic (throw) exception spec.
bool hasDynamicExceptionSpec() const {
  return isDynamicExceptionSpec(getExceptionSpecType());
}

/// Return whether this function has a noexcept exception spec.
bool hasNoexceptExceptionSpec() const {
  return isNoexceptExceptionSpec(getExceptionSpecType());
}

/// Return whether this function has a dependent exception spec.
bool hasDependentExceptionSpec() const;

/// Return whether this function has an instantiation-dependent exception
/// spec.
bool hasInstantiationDependentExceptionSpec() const;

/// Return all the available information about this type's exception spec.
ExceptionSpecInfo getExceptionSpecInfo() const {
  ExceptionSpecInfo Result;
  Result.Type = getExceptionSpecType();
  if (Result.Type == EST_Dynamic) {
    Result.Exceptions = exceptions();
  } else if (isComputedNoexcept(Result.Type)) {
    Result.NoexceptExpr = getNoexceptExpr();
  } else if (Result.Type == EST_Uninstantiated) {
    Result.SourceDecl = getExceptionSpecDecl();
    Result.SourceTemplate = getExceptionSpecTemplate();
  } else if (Result.Type == EST_Unevaluated) {
    Result.SourceDecl = getExceptionSpecDecl();
  }
  return Result;
}

/// Return the number of types in the exception specification.
unsigned getNumExceptions() const {
  return getExceptionSpecType() == EST_Dynamic
             ? getTrailingObjects<FunctionTypeExtraBitfields>()
                   ->NumExceptionType
             : 0;
}

/// Return the ith exception type, where 0 <= i < getNumExceptions().
QualType getExceptionType(unsigned i) const {
  assert(i < getNumExceptions() && "Invalid exception number!")((void)0);
  return exception_begin()[i];
}

/// Return the expression inside noexcept(expression), or a null pointer
/// if there is none (because the exception spec is not of this form).
Expr *getNoexceptExpr() const {
  if (!isComputedNoexcept(getExceptionSpecType()))
    return nullptr;
  return *getTrailingObjects<Expr *>();
}

/// If this function type has an exception specification which hasn't
/// been determined yet (either because it has not been evaluated or because
/// it has not been instantiated), this is the function whose exception
/// specification is represented by this type.
FunctionDecl *getExceptionSpecDecl() const {
  if (getExceptionSpecType() != EST_Uninstantiated &&
      getExceptionSpecType() != EST_Unevaluated)
    return nullptr;
  return getTrailingObjects<FunctionDecl *>()[0];
}

/// If this function type has an uninstantiated exception
/// specification, this is the function whose exception specification
/// should be instantiated to find the exception specification for
/// this type.
FunctionDecl *getExceptionSpecTemplate() const {
  if (getExceptionSpecType() != EST_Uninstantiated)
    return nullptr;
  return getTrailingObjects<FunctionDecl *>()[1];
}

/// Determine whether this function type has a non-throwing exception
/// specification.
CanThrowResult canThrow() const;

/// Determine whether this function type has a non-throwing exception
/// specification. If this depends on template arguments, returns
/// \c ResultIfDependent.
bool isNothrow(bool ResultIfDependent = false) const {
  return ResultIfDependent ? canThrow() != CT_Can : canThrow() == CT_Cannot;
}

/// Whether this function prototype is variadic.
bool isVariadic() const { return FunctionTypeBits.Variadic; }

SourceLocation getEllipsisLoc() const {
  return isVariadic() ? *getTrailingObjects<SourceLocation>()
                      : SourceLocation();
}

/// Determines whether this function prototype contains a
/// parameter pack at the end.
///
/// A function template whose last parameter is a parameter pack can be
/// called with an arbitrary number of arguments, much like a variadic
/// function.
bool isTemplateVariadic() const;

/// Whether this function prototype has a trailing return type.
bool hasTrailingReturn() const { return FunctionTypeBits.HasTrailingReturn; }

Qualifiers getMethodQuals() const {
  if (hasExtQualifiers())
    return *getTrailingObjects<Qualifiers>();
  else
    return getFastTypeQuals();
}

/// Retrieve the ref-qualifier associated with this function type.
RefQualifierKind getRefQualifier() const {
  return static_cast<RefQualifierKind>(FunctionTypeBits.RefQualifier);
}

using param_type_iterator = const QualType *;
using param_type_range = llvm::iterator_range<param_type_iterator>;

param_type_range param_types() const {
  return param_type_range(param_type_begin(), param_type_end());
}

param_type_iterator param_type_begin() const {
  return getTrailingObjects<QualType>();
}

param_type_iterator param_type_end() const {
  return param_type_begin() + getNumParams();
}

using exception_iterator = const QualType *;

ArrayRef<QualType> exceptions() const {
  return llvm::makeArrayRef(exception_begin(), exception_end());
}

exception_iterator exception_begin() const {
  return reinterpret_cast<exception_iterator>(
      getTrailingObjects<ExceptionType>());
}

exception_iterator exception_end() const {
  return exception_begin() + getNumExceptions();
}

/// Is there any interesting extra information for any of the parameters
/// of this function type?
bool hasExtParameterInfos() const {
  return FunctionTypeBits.HasExtParameterInfos;
}

ArrayRef<ExtParameterInfo> getExtParameterInfos() const {
  assert(hasExtParameterInfos())((void)0);
  return ArrayRef<ExtParameterInfo>(getTrailingObjects<ExtParameterInfo>(),
                                    getNumParams());
}

/// Return a pointer to the beginning of the array of extra parameter
/// information, if present, or else null if none of the parameters
/// carry it.  This is equivalent to getExtProtoInfo().ExtParameterInfos.
const ExtParameterInfo *getExtParameterInfosOrNull() const {
  if (!hasExtParameterInfos())
    return nullptr;
  return getTrailingObjects<ExtParameterInfo>();
}

ExtParameterInfo getExtParameterInfo(unsigned I) const {
  assert(I < getNumParams() && "parameter index out of range")((void)0);
  if (hasExtParameterInfos())
    return getTrailingObjects<ExtParameterInfo>()[I];
  return ExtParameterInfo();
}

ParameterABI getParameterABI(unsigned I) const {
  assert(I < getNumParams() && "parameter index out of range")((void)0);
  if (hasExtParameterInfos())
    return getTrailingObjects<ExtParameterInfo>()[I].getABI();
  return ParameterABI::Ordinary;
}

bool isParamConsumed(unsigned I) const {
  assert(I < getNumParams() && "parameter index out of range")((void)0);
  if (hasExtParameterInfos())
    return getTrailingObjects<ExtParameterInfo>()[I].isConsumed();
  return false;
}

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

void printExceptionSpecification(raw_ostream &OS,
                                 const PrintingPolicy &Policy) const;

static bool classof(const Type *T) {
  return T->getTypeClass() == FunctionProto;
}

void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Ctx);
static void Profile(llvm::FoldingSetNodeID &ID, QualType Result,
                    param_type_iterator ArgTys, unsigned NumArgs,
                    const ExtProtoInfo &EPI, const ASTContext &Context,
                    bool Canonical);
4336};

4338/// Represents the dependent type named by a dependently-scoped
4339/// typename using declaration, e.g.
4340///   using typename Base<T>::foo;
4341///
4342/// Template instantiation turns these into the underlying type.
4343class UnresolvedUsingType : public Type {
friend class ASTContext; // ASTContext creates these.

UnresolvedUsingTypenameDecl *Decl;

UnresolvedUsingType(const UnresolvedUsingTypenameDecl *D)
    : Type(UnresolvedUsing, QualType(),
           TypeDependence::DependentInstantiation),
      Decl(const_cast<UnresolvedUsingTypenameDecl *>(D)) {}

4353public:
UnresolvedUsingTypenameDecl *getDecl() const { return Decl; }

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

static bool classof(const Type *T) {
  return T->getTypeClass() == UnresolvedUsing;
}

void Profile(llvm::FoldingSetNodeID &ID) {
  return Profile(ID, Decl);
}

static void Profile(llvm::FoldingSetNodeID &ID,
                    UnresolvedUsingTypenameDecl *D) {
  ID.AddPointer(D);
}
4371};

4373class TypedefType : public Type {
TypedefNameDecl *Decl;

4376private:
friend class ASTContext; // ASTContext creates these.

TypedefType(TypeClass tc, const TypedefNameDecl *D, QualType underlying,
            QualType can);

4382public:
TypedefNameDecl *getDecl() const { return Decl; }

bool isSugared() const { return true; }
QualType desugar() const;

static bool classof(const Type *T) { return T->getTypeClass() == Typedef; }
4389};

4391/// Sugar type that represents a type that was qualified by a qualifier written
4392/// as a macro invocation.
4393class MacroQualifiedType : public Type {
friend class ASTContext; // ASTContext creates these.

QualType UnderlyingTy;
const IdentifierInfo *MacroII;

MacroQualifiedType(QualType UnderlyingTy, QualType CanonTy,
                   const IdentifierInfo *MacroII)
    : Type(MacroQualified, CanonTy, UnderlyingTy->getDependence()),
      UnderlyingTy(UnderlyingTy), MacroII(MacroII) {
  assert(isa<AttributedType>(UnderlyingTy) &&((void)0)
         "Expected a macro qualified type to only wrap attributed types.")((void)0);
}

4407public:
const IdentifierInfo *getMacroIdentifier() const { return MacroII; }
QualType getUnderlyingType() const { return UnderlyingTy; }

/// Return this attributed type's modified type with no qualifiers attached to
/// it.
QualType getModifiedType() const;

bool isSugared() const { return true; }
QualType desugar() const;

static bool classof(const Type *T) {
  return T->getTypeClass() == MacroQualified;
}
4421};

4423/// Represents a `typeof` (or __typeof__) expression (a GCC extension).
4424class TypeOfExprType : public Type {
Expr *TOExpr;

4427protected:
friend class ASTContext; // ASTContext creates these.

TypeOfExprType(Expr *E, QualType can = QualType());

4432public:
Expr *getUnderlyingExpr() const { return TOExpr; }

/// Remove a single level of sugar.
QualType desugar() const;

/// Returns whether this type directly provides sugar.
bool isSugared() const;

static bool classof(const Type *T) { return T->getTypeClass() == TypeOfExpr; }
4442};

4444/// Internal representation of canonical, dependent
4445/// `typeof(expr)` types.
4446///
4447/// This class is used internally by the ASTContext to manage
4448/// canonical, dependent types, only. Clients will only see instances
4449/// of this class via TypeOfExprType nodes.
4450class DependentTypeOfExprType
: public TypeOfExprType, public llvm::FoldingSetNode {
const ASTContext &Context;

4454public:
DependentTypeOfExprType(const ASTContext &Context, Expr *E)
    : TypeOfExprType(E), Context(Context) {}

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, Context, getUnderlyingExpr());
}

static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
                    Expr *E);
4464};

4466/// Represents `typeof(type)`, a GCC extension.
4467class TypeOfType : public Type {
friend class ASTContext; // ASTContext creates these.

QualType TOType;

TypeOfType(QualType T, QualType can)
    : Type(TypeOf, can, T->getDependence()), TOType(T) {
  assert(!isa<TypedefType>(can) && "Invalid canonical type")((void)0);
}

4477public:
QualType getUnderlyingType() const { return TOType; }

/// Remove a single level of sugar.
QualType desugar() const { return getUnderlyingType(); }

/// Returns whether this type directly provides sugar.
bool isSugared() const { return true; }

static bool classof(const Type *T) { return T->getTypeClass() == TypeOf; }
4487};

4489/// Represents the type `decltype(expr)` (C++11).
4490class DecltypeType : public Type {
Expr *E;
QualType UnderlyingType;

4494protected:
friend class ASTContext; // ASTContext creates these.

DecltypeType(Expr *E, QualType underlyingType, QualType can = QualType());

4499public:
Expr *getUnderlyingExpr() const { return E; }
QualType getUnderlyingType() const { return UnderlyingType; }

/// Remove a single level of sugar.
QualType desugar() const;

/// Returns whether this type directly provides sugar.
bool isSugared() const;

static bool classof(const Type *T) { return T->getTypeClass() == Decltype; }
4510};

4512/// Internal representation of canonical, dependent
4513/// decltype(expr) types.
4514///
4515/// This class is used internally by the ASTContext to manage
4516/// canonical, dependent types, only. Clients will only see instances
4517/// of this class via DecltypeType nodes.
4518class DependentDecltypeType : public DecltypeType, public llvm::FoldingSetNode {
const ASTContext &Context;

4521public:
DependentDecltypeType(const ASTContext &Context, Expr *E);

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, Context, getUnderlyingExpr());
}

static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
                    Expr *E);
4530};

4532/// A unary type transform, which is a type constructed from another.
4533class UnaryTransformType : public Type {
4534public:
enum UTTKind {
  EnumUnderlyingType
};

4539private:
/// The untransformed type.
QualType BaseType;

/// The transformed type if not dependent, otherwise the same as BaseType.
QualType UnderlyingType;

UTTKind UKind;

4548protected:
friend class ASTContext;

UnaryTransformType(QualType BaseTy, QualType UnderlyingTy, UTTKind UKind,
                   QualType CanonicalTy);

4554public:
bool isSugared() const { return !isDependentType(); }
QualType desugar() const { return UnderlyingType; }

QualType getUnderlyingType() const { return UnderlyingType; }
QualType getBaseType() const { return BaseType; }

UTTKind getUTTKind() const { return UKind; }

static bool classof(const Type *T) {
  return T->getTypeClass() == UnaryTransform;
}
4566};

4568/// Internal representation of canonical, dependent
4569/// __underlying_type(type) types.
4570///
4571/// This class is used internally by the ASTContext to manage
4572/// canonical, dependent types, only. Clients will only see instances
4573/// of this class via UnaryTransformType nodes.
4574class DependentUnaryTransformType : public UnaryTransformType,
                                  public llvm::FoldingSetNode {
4576public:
DependentUnaryTransformType(const ASTContext &C, QualType BaseType,
                            UTTKind UKind);

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, getBaseType(), getUTTKind());
}

static void Profile(llvm::FoldingSetNodeID &ID, QualType BaseType,
                    UTTKind UKind) {
  ID.AddPointer(BaseType.getAsOpaquePtr());
  ID.AddInteger((unsigned)UKind);
}
4589};

4591class TagType : public Type {
friend class ASTReader;
template <class T> friend class serialization::AbstractTypeReader;

/// Stores the TagDecl associated with this type. The decl may point to any
/// TagDecl that declares the entity.
TagDecl *decl;

4599protected:
TagType(TypeClass TC, const TagDecl *D, QualType can);

4602public:
TagDecl *getDecl() const;

/// Determines whether this type is in the process of being defined.
bool isBeingDefined() const;

static bool classof(const Type *T) {
  return T->getTypeClass() == Enum || T->getTypeClass() == Record;
}
4611};

4613/// A helper class that allows the use of isa/cast/dyncast
4614/// to detect TagType objects of structs/unions/classes.
4615class RecordType : public TagType {
4616protected:
friend class ASTContext; // ASTContext creates these.

explicit RecordType(const RecordDecl *D)
    : TagType(Record, reinterpret_cast<const TagDecl*>(D), QualType()) {}
explicit RecordType(TypeClass TC, RecordDecl *D)
    : TagType(TC, reinterpret_cast<const TagDecl*>(D), QualType()) {}

4624public:
RecordDecl *getDecl() const {
  return reinterpret_cast<RecordDecl*>(TagType::getDecl());
}

/// Recursively check all fields in the record for const-ness. If any field
/// is declared const, return true. Otherwise, return false.
bool hasConstFields() const;

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

static bool classof(const Type *T) { return T->getTypeClass() == Record; }
4637};

4639/// A helper class that allows the use of isa/cast/dyncast
4640/// to detect TagType objects of enums.
4641class EnumType : public TagType {
friend class ASTContext; // ASTContext creates these.

explicit EnumType(const EnumDecl *D)
    : TagType(Enum, reinterpret_cast<const TagDecl*>(D), QualType()) {}

4647public:
EnumDecl *getDecl() const {
  return reinterpret_cast<EnumDecl*>(TagType::getDecl());
}

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

static bool classof(const Type *T) { return T->getTypeClass() == Enum; }
4656};

4658/// An attributed type is a type to which a type attribute has been applied.
4659///
4660/// The "modified type" is the fully-sugared type to which the attributed
4661/// type was applied; generally it is not canonically equivalent to the
4662/// attributed type. The "equivalent type" is the minimally-desugared type
4663/// which the type is canonically equivalent to.
4664///
4665/// For example, in the following attributed type:
4666///     int32_t __attribute__((vector_size(16)))
4667///   - the modified type is the TypedefType for int32_t
4668///   - the equivalent type is VectorType(16, int32_t)
4669///   - the canonical type is VectorType(16, int)
4670class AttributedType : public Type, public llvm::FoldingSetNode {
4671public:
using Kind = attr::Kind;

4674private:
friend class ASTContext; // ASTContext creates these

QualType ModifiedType;
QualType EquivalentType;

AttributedType(QualType canon, attr::Kind attrKind, QualType modified,
               QualType equivalent)
    : Type(Attributed, canon, equivalent->getDependence()),
      ModifiedType(modified), EquivalentType(equivalent) {
  AttributedTypeBits.AttrKind = attrKind;
}

4687public:
Kind getAttrKind() const {
  return static_cast<Kind>(AttributedTypeBits.AttrKind);
}

QualType getModifiedType() const { return ModifiedType; }
QualType getEquivalentType() const { return EquivalentType; }

bool isSugared() const { return true; }
QualType desugar() const { return getEquivalentType(); }

/// Does this attribute behave like a type qualifier?
///
/// A type qualifier adjusts a type to provide specialized rules for
/// a specific object, like the standard const and volatile qualifiers.
/// This includes attributes controlling things like nullability,
/// address spaces, and ARC ownership.  The value of the object is still
/// largely described by the modified type.
///
/// In contrast, many type attributes "rewrite" their modified type to
/// produce a fundamentally different type, not necessarily related in any
/// formalizable way to the original type.  For example, calling convention
/// and vector attributes are not simple type qualifiers.
///
/// Type qualifiers are often, but not always, reflected in the canonical
/// type.
bool isQualifier() const;

bool isMSTypeSpec() const;

bool isCallingConv() const;

llvm::Optional<NullabilityKind> getImmediateNullability() const;

/// Retrieve the attribute kind corresponding to the given
/// nullability kind.
static Kind getNullabilityAttrKind(NullabilityKind kind) {
  switch (kind) {
  case NullabilityKind::NonNull:
    return attr::TypeNonNull;

  case NullabilityKind::Nullable:
    return attr::TypeNullable;

  case NullabilityKind::NullableResult:
    return attr::TypeNullableResult;

  case NullabilityKind::Unspecified:
    return attr::TypeNullUnspecified;
  }
  llvm_unreachable("Unknown nullability kind.")__builtin_unreachable();
}

/// Strip off the top-level nullability annotation on the given
/// type, if it's there.
///
/// \param T The type to strip. If the type is exactly an
/// AttributedType specifying nullability (without looking through
/// type sugar), the nullability is returned and this type changed
/// to the underlying modified type.
///
/// \returns the top-level nullability, if present.
static Optional<NullabilityKind> stripOuterNullability(QualType &T);

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, getAttrKind(), ModifiedType, EquivalentType);
}

static void Profile(llvm::FoldingSetNodeID &ID, Kind attrKind,
                    QualType modified, QualType equivalent) {
  ID.AddInteger(attrKind);
  ID.AddPointer(modified.getAsOpaquePtr());
  ID.AddPointer(equivalent.getAsOpaquePtr());
}

static bool classof(const Type *T) {
  return T->getTypeClass() == Attributed;
}
4765};

4767class TemplateTypeParmType : public Type, public llvm::FoldingSetNode {
friend class ASTContext; // ASTContext creates these

// Helper data collector for canonical types.
struct CanonicalTTPTInfo {
  unsigned Depth : 15;
  unsigned ParameterPack : 1;
  unsigned Index : 16;
};

union {
  // Info for the canonical type.
  CanonicalTTPTInfo CanTTPTInfo;

  // Info for the non-canonical type.
  TemplateTypeParmDecl *TTPDecl;
};

/// Build a non-canonical type.
TemplateTypeParmType(TemplateTypeParmDecl *TTPDecl, QualType Canon)
    : Type(TemplateTypeParm, Canon,
           TypeDependence::DependentInstantiation |
               (Canon->getDependence() & TypeDependence::UnexpandedPack)),
      TTPDecl(TTPDecl) {}

/// Build the canonical type.
TemplateTypeParmType(unsigned D, unsigned I, bool PP)
    : Type(TemplateTypeParm, QualType(this, 0),
           TypeDependence::DependentInstantiation |
               (PP ? TypeDependence::UnexpandedPack : TypeDependence::None)) {
  CanTTPTInfo.Depth = D;
  CanTTPTInfo.Index = I;
  CanTTPTInfo.ParameterPack = PP;
}

const CanonicalTTPTInfo& getCanTTPTInfo() const {
  QualType Can = getCanonicalTypeInternal();
  return Can->castAs<TemplateTypeParmType>()->CanTTPTInfo;
}

4807public:
unsigned getDepth() const { return getCanTTPTInfo().Depth; }
unsigned getIndex() const { return getCanTTPTInfo().Index; }
bool isParameterPack() const { return getCanTTPTInfo().ParameterPack; }

TemplateTypeParmDecl *getDecl() const {
  return isCanonicalUnqualified() ? nullptr : TTPDecl;
}

IdentifierInfo *getIdentifier() const;

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, getDepth(), getIndex(), isParameterPack(), getDecl());
}

static void Profile(llvm::FoldingSetNodeID &ID, unsigned Depth,
                    unsigned Index, bool ParameterPack,
                    TemplateTypeParmDecl *TTPDecl) {
  ID.AddInteger(Depth);
  ID.AddInteger(Index);
  ID.AddBoolean(ParameterPack);
  ID.AddPointer(TTPDecl);
}

static bool classof(const Type *T) {
  return T->getTypeClass() == TemplateTypeParm;
}
4837};

4839/// Represents the result of substituting a type for a template
4840/// type parameter.
4841///
4842/// Within an instantiated template, all template type parameters have
4843/// been replaced with these.  They are used solely to record that a
4844/// type was originally written as a template type parameter;
4845/// therefore they are never canonical.
4846class SubstTemplateTypeParmType : public Type, public llvm::FoldingSetNode {
friend class ASTContext;

// The original type parameter.
const TemplateTypeParmType *Replaced;

SubstTemplateTypeParmType(const TemplateTypeParmType *Param, QualType Canon)
    : Type(SubstTemplateTypeParm, Canon, Canon->getDependence()),
      Replaced(Param) {}

4856public:
/// Gets the template parameter that was substituted for.
const TemplateTypeParmType *getReplacedParameter() const {
  return Replaced;
}

/// Gets the type that was substituted for the template
/// parameter.
QualType getReplacementType() const {
  return getCanonicalTypeInternal();
}

bool isSugared() const { return true; }
QualType desugar() const { return getReplacementType(); }

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, getReplacedParameter(), getReplacementType());
}

static void Profile(llvm::FoldingSetNodeID &ID,
                    const TemplateTypeParmType *Replaced,
                    QualType Replacement) {
  ID.AddPointer(Replaced);
  ID.AddPointer(Replacement.getAsOpaquePtr());
}

static bool classof(const Type *T) {
  return T->getTypeClass() == SubstTemplateTypeParm;
}
4885};

4887/// Represents the result of substituting a set of types for a template
4888/// type parameter pack.
4889///
4890/// When a pack expansion in the source code contains multiple parameter packs
4891/// and those parameter packs correspond to different levels of template
4892/// parameter lists, this type node is used to represent a template type
4893/// parameter pack from an outer level, which has already had its argument pack
4894/// substituted but that still lives within a pack expansion that itself
4895/// could not be instantiated. When actually performing a substitution into
4896/// that pack expansion (e.g., when all template parameters have corresponding
4897/// arguments), this type will be replaced with the \c SubstTemplateTypeParmType
4898/// at the current pack substitution index.
4899class SubstTemplateTypeParmPackType : public Type, public llvm::FoldingSetNode {
friend class ASTContext;

/// The original type parameter.
const TemplateTypeParmType *Replaced;

/// A pointer to the set of template arguments that this
/// parameter pack is instantiated with.
const TemplateArgument *Arguments;

SubstTemplateTypeParmPackType(const TemplateTypeParmType *Param,
                              QualType Canon,
                              const TemplateArgument &ArgPack);

4913public:
IdentifierInfo *getIdentifier() const { return Replaced->getIdentifier(); }

/// Gets the template parameter that was substituted for.
const TemplateTypeParmType *getReplacedParameter() const {
  return Replaced;
}

unsigned getNumArgs() const {
  return SubstTemplateTypeParmPackTypeBits.NumArgs;
}

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

TemplateArgument getArgumentPack() const;

void Profile(llvm::FoldingSetNodeID &ID);
static void Profile(llvm::FoldingSetNodeID &ID,
                    const TemplateTypeParmType *Replaced,
                    const TemplateArgument &ArgPack);

static bool classof(const Type *T) {
  return T->getTypeClass() == SubstTemplateTypeParmPack;
}
4938};

4940/// Common base class for placeholders for types that get replaced by
4941/// placeholder type deduction: C++11 auto, C++14 decltype(auto), C++17 deduced
4942/// class template types, and constrained type names.
4943///
4944/// These types are usually a placeholder for a deduced type. However, before
4945/// the initializer is attached, or (usually) if the initializer is
4946/// type-dependent, there is no deduced type and the type is canonical. In
4947/// the latter case, it is also a dependent type.
4948class DeducedType : public Type {
4949protected:
DeducedType(TypeClass TC, QualType DeducedAsType,
            TypeDependence ExtraDependence)
    : Type(TC,
           // FIXME: Retain the sugared deduced type?
           DeducedAsType.isNull() ? QualType(this, 0)
                                  : DeducedAsType.getCanonicalType(),
           ExtraDependence | (DeducedAsType.isNull()
                                  ? TypeDependence::None
                                  : DeducedAsType->getDependence() &
                                        ~TypeDependence::VariablyModified)) {}

4961public:
bool isSugared() const { return !isCanonicalUnqualified(); }
QualType desugar() const { return getCanonicalTypeInternal(); }

/// Get the type deduced for this placeholder type, or null if it's
/// either not been deduced or was deduced to a dependent type.
QualType getDeducedType() const {
  return !isCanonicalUnqualified() ? getCanonicalTypeInternal() : QualType();
}
bool isDeduced() const {
  return !isCanonicalUnqualified() || isDependentType();
}

static bool classof(const Type *T) {
  return T->getTypeClass() == Auto ||
         T->getTypeClass() == DeducedTemplateSpecialization;
}
4978};

4980/// Represents a C++11 auto or C++14 decltype(auto) type, possibly constrained
4981/// by a type-constraint.
4982class alignas(8) AutoType : public DeducedType, public llvm::FoldingSetNode {
friend class ASTContext; // ASTContext creates these

ConceptDecl *TypeConstraintConcept;

AutoType(QualType DeducedAsType, AutoTypeKeyword Keyword,
         TypeDependence ExtraDependence, ConceptDecl *CD,
         ArrayRef<TemplateArgument> TypeConstraintArgs);

const TemplateArgument *getArgBuffer() const {
  return reinterpret_cast<const TemplateArgument*>(this+1);
}

TemplateArgument *getArgBuffer() {
  return reinterpret_cast<TemplateArgument*>(this+1);
}

4999public:
/// Retrieve the template arguments.
const TemplateArgument *getArgs() const {
  return getArgBuffer();
}

/// Retrieve the number of template arguments.
unsigned getNumArgs() const {
  return AutoTypeBits.NumArgs;
}

const TemplateArgument &getArg(unsigned Idx) const; // in TemplateBase.h

ArrayRef<TemplateArgument> getTypeConstraintArguments() const {
  return {getArgs(), getNumArgs()};
}

ConceptDecl *getTypeConstraintConcept() const {
  return TypeConstraintConcept;
}

bool isConstrained() const {
  return TypeConstraintConcept != nullptr;
}

bool isDecltypeAuto() const {
  return getKeyword() == AutoTypeKeyword::DecltypeAuto;
}

AutoTypeKeyword getKeyword() const {
  return (AutoTypeKeyword)AutoTypeBits.Keyword;
}

void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context) {
  Profile(ID, Context, getDeducedType(), getKeyword(), isDependentType(),
          getTypeConstraintConcept(), getTypeConstraintArguments());
}

static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
                    QualType Deduced, AutoTypeKeyword Keyword,
                    bool IsDependent, ConceptDecl *CD,
                    ArrayRef<TemplateArgument> Arguments);

static bool classof(const Type *T) {
  return T->getTypeClass() == Auto;
}
5045};

5047/// Represents a C++17 deduced template specialization type.
5048class DeducedTemplateSpecializationType : public DeducedType,
                                        public llvm::FoldingSetNode {
friend class ASTContext; // ASTContext creates these

/// The name of the template whose arguments will be deduced.
TemplateName Template;

DeducedTemplateSpecializationType(TemplateName Template,
                                  QualType DeducedAsType,
                                  bool IsDeducedAsDependent)
    : DeducedType(DeducedTemplateSpecialization, DeducedAsType,
                  toTypeDependence(Template.getDependence()) |
                      (IsDeducedAsDependent
                           ? TypeDependence::DependentInstantiation
                           : TypeDependence::None)),
      Template(Template) {}

5065public:
/// Retrieve the name of the template that we are deducing.
TemplateName getTemplateName() const { return Template;}

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, getTemplateName(), getDeducedType(), isDependentType());
}

static void Profile(llvm::FoldingSetNodeID &ID, TemplateName Template,
                    QualType Deduced, bool IsDependent) {
  Template.Profile(ID);
  ID.AddPointer(Deduced.getAsOpaquePtr());
  ID.AddBoolean(IsDependent);
}

static bool classof(const Type *T) {
  return T->getTypeClass() == DeducedTemplateSpecialization;
}
5083};

5085/// Represents a type template specialization; the template
5086/// must be a class template, a type alias template, or a template
5087/// template parameter.  A template which cannot be resolved to one of
5088/// these, e.g. because it is written with a dependent scope
5089/// specifier, is instead represented as a
5090/// @c DependentTemplateSpecializationType.
5091///
5092/// A non-dependent template specialization type is always "sugar",
5093/// typically for a \c RecordType.  For example, a class template
5094/// specialization type of \c vector<int> will refer to a tag type for
5095/// the instantiation \c std::vector<int, std::allocator<int>>
5096///
5097/// Template specializations are dependent if either the template or
5098/// any of the template arguments are dependent, in which case the
5099/// type may also be canonical.
5100///
5101/// Instances of this type are allocated with a trailing array of
5102/// TemplateArguments, followed by a QualType representing the
5103/// non-canonical aliased type when the template is a type alias
5104/// template.
5105class alignas(8) TemplateSpecializationType
  : public Type,
    public llvm::FoldingSetNode {
friend class ASTContext; // ASTContext creates these

/// The name of the template being specialized.  This is
/// either a TemplateName::Template (in which case it is a
/// ClassTemplateDecl*, a TemplateTemplateParmDecl*, or a
/// TypeAliasTemplateDecl*), a
/// TemplateName::SubstTemplateTemplateParmPack, or a
/// TemplateName::SubstTemplateTemplateParm (in which case the
/// replacement must, recursively, be one of these).
TemplateName Template;

TemplateSpecializationType(TemplateName T,
                           ArrayRef<TemplateArgument> Args,
                           QualType Canon,
                           QualType Aliased);

5124public:
/// Determine whether any of the given template arguments are dependent.
///
/// The converted arguments should be supplied when known; whether an
/// argument is dependent can depend on the conversions performed on it
/// (for example, a 'const int' passed as a template argument might be
/// dependent if the parameter is a reference but non-dependent if the
/// parameter is an int).
///
/// Note that the \p Args parameter is unused: this is intentional, to remind
/// the caller that they need to pass in the converted arguments, not the
/// specified arguments.
static bool
anyDependentTemplateArguments(ArrayRef<TemplateArgumentLoc> Args,
                              ArrayRef<TemplateArgument> Converted);
static bool
anyDependentTemplateArguments(const TemplateArgumentListInfo &,
                              ArrayRef<TemplateArgument> Converted);
static bool anyInstantiationDependentTemplateArguments(
    ArrayRef<TemplateArgumentLoc> Args);

/// True if this template specialization type matches a current
/// instantiation in the context in which it is found.
bool isCurrentInstantiation() const {
  return isa<InjectedClassNameType>(getCanonicalTypeInternal());
}

/// Determine if this template specialization type is for a type alias
/// template that has been substituted.
///
/// Nearly every template specialization type whose template is an alias
/// template will be substituted. However, this is not the case when
/// the specialization contains a pack expansion but the template alias
/// does not have a corresponding parameter pack, e.g.,
///
/// \code
/// template<typename T, typename U, typename V> struct S;
/// template<typename T, typename U> using A = S<T, int, U>;
/// template<typename... Ts> struct X {
///   typedef A<Ts...> type; // not a type alias
/// };
/// \endcode
bool isTypeAlias() const { return TemplateSpecializationTypeBits.TypeAlias; }

/// Get the aliased type, if this is a specialization of a type alias
/// template.
QualType getAliasedType() const {
  assert(isTypeAlias() && "not a type alias template specialization")((void)0);
  return *reinterpret_cast<const QualType*>(end());
}

using iterator = const TemplateArgument *;

iterator begin() const { return getArgs(); }
iterator end() const; // defined inline in TemplateBase.h

/// Retrieve the name of the template that we are specializing.
TemplateName getTemplateName() const { return Template; }

/// Retrieve the template arguments.
const TemplateArgument *getArgs() const {
  return reinterpret_cast<const TemplateArgument *>(this + 1);
}

/// Retrieve the number of template arguments.
unsigned getNumArgs() const {
  return TemplateSpecializationTypeBits.NumArgs;
}

/// Retrieve a specific template argument as a type.
/// \pre \c isArgType(Arg)
const TemplateArgument &getArg(unsigned Idx) const; // in TemplateBase.h

ArrayRef<TemplateArgument> template_arguments() const {
  return {getArgs(), getNumArgs()};
}

bool isSugared() const {
  return !isDependentType() || isCurrentInstantiation() || isTypeAlias();
}

QualType desugar() const {
  return isTypeAlias() ? getAliasedType() : getCanonicalTypeInternal();
}

void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Ctx) {
  Profile(ID, Template, template_arguments(), Ctx);
  if (isTypeAlias())
    getAliasedType().Profile(ID);
}

static void Profile(llvm::FoldingSetNodeID &ID, TemplateName T,
                    ArrayRef<TemplateArgument> Args,
                    const ASTContext &Context);

static bool classof(const Type *T) {
  return T->getTypeClass() == TemplateSpecialization;
}
5222};

5224/// Print a template argument list, including the '<' and '>'
5225/// enclosing the template arguments.
5226void printTemplateArgumentList(raw_ostream &OS,
                             ArrayRef<TemplateArgument> Args,
                             const PrintingPolicy &Policy,
                             const TemplateParameterList *TPL = nullptr);

5231void printTemplateArgumentList(raw_ostream &OS,
                             ArrayRef<TemplateArgumentLoc> Args,
                             const PrintingPolicy &Policy,
                             const TemplateParameterList *TPL = nullptr);

5236void printTemplateArgumentList(raw_ostream &OS,
                             const TemplateArgumentListInfo &Args,
                             const PrintingPolicy &Policy,
                             const TemplateParameterList *TPL = nullptr);

5241/// The injected class name of a C++ class template or class
5242/// template partial specialization.  Used to record that a type was
5243/// spelled with a bare identifier rather than as a template-id; the
5244/// equivalent for non-templated classes is just RecordType.
5245///
5246/// Injected class name types are always dependent.  Template
5247/// instantiation turns these into RecordTypes.
5248///
5249/// Injected class name types are always canonical.  This works
5250/// because it is impossible to compare an injected class name type
5251/// with the corresponding non-injected template type, for the same
5252/// reason that it is impossible to directly compare template
5253/// parameters from different dependent contexts: injected class name
5254/// types can only occur within the scope of a particular templated
5255/// declaration, and within that scope every template specialization
5256/// will canonicalize to the injected class name (when appropriate
5257/// according to the rules of the language).
5258class InjectedClassNameType : public Type {
friend class ASTContext; // ASTContext creates these.
friend class ASTNodeImporter;
friend class ASTReader; // FIXME: ASTContext::getInjectedClassNameType is not
                        // currently suitable for AST reading, too much
                        // interdependencies.
template <class T> friend class serialization::AbstractTypeReader;

CXXRecordDecl *Decl;

/// The template specialization which this type represents.
/// For example, in
///   template <class T> class A { ... };
/// this is A<T>, whereas in
///   template <class X, class Y> class A<B<X,Y> > { ... };
/// this is A<B<X,Y> >.
///
/// It is always unqualified, always a template specialization type,
/// and always dependent.
QualType InjectedType;

InjectedClassNameType(CXXRecordDecl *D, QualType TST)
    : Type(InjectedClassName, QualType(),
           TypeDependence::DependentInstantiation),
      Decl(D), InjectedType(TST) {
  assert(isa<TemplateSpecializationType>(TST))((void)0);
  assert(!TST.hasQualifiers())((void)0);
  assert(TST->isDependentType())((void)0);
}

5288public:
QualType getInjectedSpecializationType() const { return InjectedType; }

const TemplateSpecializationType *getInjectedTST() const {
  return cast<TemplateSpecializationType>(InjectedType.getTypePtr());
}

TemplateName getTemplateName() const {
  return getInjectedTST()->getTemplateName();
}

CXXRecordDecl *getDecl() const;

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

static bool classof(const Type *T) {
  return T->getTypeClass() == InjectedClassName;
}
5307};

5309/// The kind of a tag type.
5310enum TagTypeKind {
/// The "struct" keyword.
TTK_Struct,

/// The "__interface" keyword.
TTK_Interface,

/// The "union" keyword.
TTK_Union,

/// The "class" keyword.
TTK_Class,

/// The "enum" keyword.
TTK_Enum
5325};

5327/// The elaboration keyword that precedes a qualified type name or
5328/// introduces an elaborated-type-specifier.
5329enum ElaboratedTypeKeyword {
/// The "struct" keyword introduces the elaborated-type-specifier.
ETK_Struct,

/// The "__interface" keyword introduces the elaborated-type-specifier.
ETK_Interface,

/// The "union" keyword introduces the elaborated-type-specifier.
ETK_Union,

/// The "class" keyword introduces the elaborated-type-specifier.
ETK_Class,

/// The "enum" keyword introduces the elaborated-type-specifier.
ETK_Enum,

/// The "typename" keyword precedes the qualified type name, e.g.,
/// \c typename T::type.
ETK_Typename,

/// No keyword precedes the qualified type name.
ETK_None
5351};

5353/// A helper class for Type nodes having an ElaboratedTypeKeyword.
5354/// The keyword in stored in the free bits of the base class.
5355/// Also provides a few static helpers for converting and printing
5356/// elaborated type keyword and tag type kind enumerations.
5357class TypeWithKeyword : public Type {
5358protected:
TypeWithKeyword(ElaboratedTypeKeyword Keyword, TypeClass tc,
                QualType Canonical, TypeDependence Dependence)
    : Type(tc, Canonical, Dependence) {
  TypeWithKeywordBits.Keyword = Keyword;
}

5365public:
ElaboratedTypeKeyword getKeyword() const {
  return static_cast<ElaboratedTypeKeyword>(TypeWithKeywordBits.Keyword);
}

/// Converts a type specifier (DeclSpec::TST) into an elaborated type keyword.
static ElaboratedTypeKeyword getKeywordForTypeSpec(unsigned TypeSpec);

/// Converts a type specifier (DeclSpec::TST) into a tag type kind.
/// It is an error to provide a type specifier which *isn't* a tag kind here.
static TagTypeKind getTagTypeKindForTypeSpec(unsigned TypeSpec);

/// Converts a TagTypeKind into an elaborated type keyword.
static ElaboratedTypeKeyword getKeywordForTagTypeKind(TagTypeKind Tag);

/// Converts an elaborated type keyword into a TagTypeKind.
/// It is an error to provide an elaborated type keyword
/// which *isn't* a tag kind here.
static TagTypeKind getTagTypeKindForKeyword(ElaboratedTypeKeyword Keyword);

static bool KeywordIsTagTypeKind(ElaboratedTypeKeyword Keyword);

static StringRef getKeywordName(ElaboratedTypeKeyword Keyword);

static StringRef getTagTypeKindName(TagTypeKind Kind) {
  return getKeywordName(getKeywordForTagTypeKind(Kind));
}

class CannotCastToThisType {};
static CannotCastToThisType classof(const Type *);
5395};

5397/// Represents a type that was referred to using an elaborated type
5398/// keyword, e.g., struct S, or via a qualified name, e.g., N::M::type,
5399/// or both.
5400///
5401/// This type is used to keep track of a type name as written in the
5402/// source code, including tag keywords and any nested-name-specifiers.
5403/// The type itself is always "sugar", used to express what was written
5404/// in the source code but containing no additional semantic information.
5405class ElaboratedType final
  : public TypeWithKeyword,
    public llvm::FoldingSetNode,
    private llvm::TrailingObjects<ElaboratedType, TagDecl *> {
friend class ASTContext; // ASTContext creates these
friend TrailingObjects;

/// The nested name specifier containing the qualifier.
NestedNameSpecifier *NNS;

/// The type that this qualified name refers to.
QualType NamedType;

/// The (re)declaration of this tag type owned by this occurrence is stored
/// as a trailing object if there is one. Use getOwnedTagDecl to obtain
/// it, or obtain a null pointer if there is none.

ElaboratedType(ElaboratedTypeKeyword Keyword, NestedNameSpecifier *NNS,
               QualType NamedType, QualType CanonType, TagDecl *OwnedTagDecl)
    : TypeWithKeyword(Keyword, Elaborated, CanonType,
                      // Any semantic dependence on the qualifier will have
                      // been incorporated into NamedType. We still need to
                      // track syntactic (instantiation / error / pack)
                      // dependence on the qualifier.
                      NamedType->getDependence() |
                          (NNS ? toSyntacticDependence(
                                     toTypeDependence(NNS->getDependence()))
                               : TypeDependence::None)),
      NNS(NNS), NamedType(NamedType) {
  ElaboratedTypeBits.HasOwnedTagDecl = false;
  if (OwnedTagDecl) {
    ElaboratedTypeBits.HasOwnedTagDecl = true;
    *getTrailingObjects<TagDecl *>() = OwnedTagDecl;
  }
  assert(!(Keyword == ETK_None && NNS == nullptr) &&((void)0)
         "ElaboratedType cannot have elaborated type keyword "((void)0)
         "and name qualifier both null.")((void)0);
}

5444public:
/// Retrieve the qualification on this type.
NestedNameSpecifier *getQualifier() const { return NNS; }

/// Retrieve the type named by the qualified-id.
QualType getNamedType() const { return NamedType; }

/// Remove a single level of sugar.
QualType desugar() const { return getNamedType(); }

/// Returns whether this type directly provides sugar.
bool isSugared() const { return true; }

/// Return the (re)declaration of this type owned by this occurrence of this
/// type, or nullptr if there is none.
TagDecl *getOwnedTagDecl() const {
  return ElaboratedTypeBits.HasOwnedTagDecl ? *getTrailingObjects<TagDecl *>()
                                            : nullptr;
}

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, getKeyword(), NNS, NamedType, getOwnedTagDecl());
}

static void Profile(llvm::FoldingSetNodeID &ID, ElaboratedTypeKeyword Keyword,
                    NestedNameSpecifier *NNS, QualType NamedType,
                    TagDecl *OwnedTagDecl) {
  ID.AddInteger(Keyword);
  ID.AddPointer(NNS);
  NamedType.Profile(ID);
  ID.AddPointer(OwnedTagDecl);
}

static bool classof(const Type *T) { return T->getTypeClass() == Elaborated; }
5478};

5480/// Represents a qualified type name for which the type name is
5481/// dependent.
5482///
5483/// DependentNameType represents a class of dependent types that involve a
5484/// possibly dependent nested-name-specifier (e.g., "T::") followed by a
5485/// name of a type. The DependentNameType may start with a "typename" (for a
5486/// typename-specifier), "class", "struct", "union", or "enum" (for a
5487/// dependent elaborated-type-specifier), or nothing (in contexts where we
5488/// know that we must be referring to a type, e.g., in a base class specifier).
5489/// Typically the nested-name-specifier is dependent, but in MSVC compatibility
5490/// mode, this type is used with non-dependent names to delay name lookup until
5491/// instantiation.
5492class DependentNameType : public TypeWithKeyword, public llvm::FoldingSetNode {
friend class ASTContext; // ASTContext creates these

/// The nested name specifier containing the qualifier.
NestedNameSpecifier *NNS;

/// The type that this typename specifier refers to.
const IdentifierInfo *Name;

DependentNameType(ElaboratedTypeKeyword Keyword, NestedNameSpecifier *NNS,
                  const IdentifierInfo *Name, QualType CanonType)
    : TypeWithKeyword(Keyword, DependentName, CanonType,
                      TypeDependence::DependentInstantiation |
                          toTypeDependence(NNS->getDependence())),
      NNS(NNS), Name(Name) {}

5508public:
/// Retrieve the qualification on this type.
NestedNameSpecifier *getQualifier() const { return NNS; }

/// Retrieve the type named by the typename specifier as an identifier.
///
/// This routine will return a non-NULL identifier pointer when the
/// form of the original typename was terminated by an identifier,
/// e.g., "typename T::type".
const IdentifierInfo *getIdentifier() const {
  return Name;
}

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, getKeyword(), NNS, Name);
}

static void Profile(llvm::FoldingSetNodeID &ID, ElaboratedTypeKeyword Keyword,
                    NestedNameSpecifier *NNS, const IdentifierInfo *Name) {
  ID.AddInteger(Keyword);
  ID.AddPointer(NNS);
  ID.AddPointer(Name);
}

static bool classof(const Type *T) {
  return T->getTypeClass() == DependentName;
}
5538};

5540/// Represents a template specialization type whose template cannot be
5541/// resolved, e.g.
5542///   A<T>::template B<T>
5543class alignas(8) DependentTemplateSpecializationType
  : public TypeWithKeyword,
    public llvm::FoldingSetNode {
friend class ASTContext; // ASTContext creates these

/// The nested name specifier containing the qualifier.
NestedNameSpecifier *NNS;

/// The identifier of the template.
const IdentifierInfo *Name;

DependentTemplateSpecializationType(ElaboratedTypeKeyword Keyword,
                                    NestedNameSpecifier *NNS,
                                    const IdentifierInfo *Name,
                                    ArrayRef<TemplateArgument> Args,
                                    QualType Canon);

const TemplateArgument *getArgBuffer() const {
  return reinterpret_cast<const TemplateArgument*>(this+1);
}

TemplateArgument *getArgBuffer() {
  return reinterpret_cast<TemplateArgument*>(this+1);
}

5568public:
NestedNameSpecifier *getQualifier() const { return NNS; }
const IdentifierInfo *getIdentifier() const { return Name; }

/// Retrieve the template arguments.
const TemplateArgument *getArgs() const {
  return getArgBuffer();
}

/// Retrieve the number of template arguments.
unsigned getNumArgs() const {
  return DependentTemplateSpecializationTypeBits.NumArgs;
}

const TemplateArgument &getArg(unsigned Idx) const; // in TemplateBase.h

ArrayRef<TemplateArgument> template_arguments() const {
  return {getArgs(), getNumArgs()};
}

using iterator = const TemplateArgument *;

iterator begin() const { return getArgs(); }
iterator end() const; // inline in TemplateBase.h

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context) {
  Profile(ID, Context, getKeyword(), NNS, Name, {getArgs(), getNumArgs()});
}

static void Profile(llvm::FoldingSetNodeID &ID,
                    const ASTContext &Context,
                    ElaboratedTypeKeyword Keyword,
                    NestedNameSpecifier *Qualifier,
                    const IdentifierInfo *Name,
                    ArrayRef<TemplateArgument> Args);

static bool classof(const Type *T) {
  return T->getTypeClass() == DependentTemplateSpecialization;
}
5610};

5612/// Represents a pack expansion of types.
5613///
5614/// Pack expansions are part of C++11 variadic templates. A pack
5615/// expansion contains a pattern, which itself contains one or more
5616/// "unexpanded" parameter packs. When instantiated, a pack expansion
5617/// produces a series of types, each instantiated from the pattern of
5618/// the expansion, where the Ith instantiation of the pattern uses the
5619/// Ith arguments bound to each of the unexpanded parameter packs. The
5620/// pack expansion is considered to "expand" these unexpanded
5621/// parameter packs.
5622///
5623/// \code
5624/// template<typename ...Types> struct tuple;
5625///
5626/// template<typename ...Types>
5627/// struct tuple_of_references {
5628///   typedef tuple<Types&...> type;
5629/// };
5630/// \endcode
5631///
5632/// Here, the pack expansion \c Types&... is represented via a
5633/// PackExpansionType whose pattern is Types&.
5634class PackExpansionType : public Type, public llvm::FoldingSetNode {
friend class ASTContext; // ASTContext creates these

/// The pattern of the pack expansion.
QualType Pattern;

PackExpansionType(QualType Pattern, QualType Canon,
                  Optional<unsigned> NumExpansions)
    : Type(PackExpansion, Canon,
           (Pattern->getDependence() | TypeDependence::Dependent |
            TypeDependence::Instantiation) &
               ~TypeDependence::UnexpandedPack),
      Pattern(Pattern) {
  PackExpansionTypeBits.NumExpansions =
      NumExpansions ? *NumExpansions + 1 : 0;
}

5651public:
/// Retrieve the pattern of this pack expansion, which is the
/// type that will be repeatedly instantiated when instantiating the
/// pack expansion itself.
QualType getPattern() const { return Pattern; }

/// Retrieve the number of expansions that this pack expansion will
/// generate, if known.
Optional<unsigned> getNumExpansions() const {
  if (PackExpansionTypeBits.NumExpansions)
    return PackExpansionTypeBits.NumExpansions - 1;
  return None;
}

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, getPattern(), getNumExpansions());
}

static void Profile(llvm::FoldingSetNodeID &ID, QualType Pattern,
                    Optional<unsigned> NumExpansions) {
  ID.AddPointer(Pattern.getAsOpaquePtr());
  ID.AddBoolean(NumExpansions.hasValue());
  if (NumExpansions)
    ID.AddInteger(*NumExpansions);
}

static bool classof(const Type *T) {
  return T->getTypeClass() == PackExpansion;
}
5683};

5685/// This class wraps the list of protocol qualifiers. For types that can
5686/// take ObjC protocol qualifers, they can subclass this class.
5687template <class T>
5688class ObjCProtocolQualifiers {
5689protected:
ObjCProtocolQualifiers() = default;

ObjCProtocolDecl * const *getProtocolStorage() const {
  return const_cast<ObjCProtocolQualifiers*>(this)->getProtocolStorage();
}

ObjCProtocolDecl **getProtocolStorage() {
  return static_cast<T*>(this)->getProtocolStorageImpl();
}

void setNumProtocols(unsigned N) {
  static_cast<T*>(this)->setNumProtocolsImpl(N);
}

void initialize(ArrayRef<ObjCProtocolDecl *> protocols) {
  setNumProtocols(protocols.size());
  assert(getNumProtocols() == protocols.size() &&((void)0)
         "bitfield overflow in protocol count")((void)0);
  if (!protocols.empty())
    memcpy(getProtocolStorage(), protocols.data(),
           protocols.size() * sizeof(ObjCProtocolDecl*));
}

5713public:
using qual_iterator = ObjCProtocolDecl * const *;
using qual_range = llvm::iterator_range<qual_iterator>;

qual_range quals() const { return qual_range(qual_begin(), qual_end()); }
qual_iterator qual_begin() const { return getProtocolStorage(); }
qual_iterator qual_end() const { return qual_begin() + getNumProtocols(); }

bool qual_empty() const { return getNumProtocols() == 0; }

/// Return the number of qualifying protocols in this type, or 0 if
/// there are none.
unsigned getNumProtocols() const {
  return static_cast<const T*>(this)->getNumProtocolsImpl();
}

/// Fetch a protocol by index.
ObjCProtocolDecl *getProtocol(unsigned I) const {
  assert(I < getNumProtocols() && "Out-of-range protocol access")((void)0);
  return qual_begin()[I];
}

/// Retrieve all of the protocol qualifiers.
ArrayRef<ObjCProtocolDecl *> getProtocols() const {
  return ArrayRef<ObjCProtocolDecl *>(qual_begin(), getNumProtocols());
}
5739};

5741/// Represents a type parameter type in Objective C. It can take
5742/// a list of protocols.
5743class ObjCTypeParamType : public Type,
                        public ObjCProtocolQualifiers<ObjCTypeParamType>,
                        public llvm::FoldingSetNode {
friend class ASTContext;
friend class ObjCProtocolQualifiers<ObjCTypeParamType>;

/// The number of protocols stored on this type.
unsigned NumProtocols : 6;

ObjCTypeParamDecl *OTPDecl;

/// The protocols are stored after the ObjCTypeParamType node. In the
/// canonical type, the list of protocols are sorted alphabetically
/// and uniqued.
ObjCProtocolDecl **getProtocolStorageImpl();

/// Return the number of qualifying protocols in this interface type,
/// or 0 if there are none.
unsigned getNumProtocolsImpl() const {
  return NumProtocols;
}

void setNumProtocolsImpl(unsigned N) {
  NumProtocols = N;
}

ObjCTypeParamType(const ObjCTypeParamDecl *D,
                  QualType can,
                  ArrayRef<ObjCProtocolDecl *> protocols);

5773public:
bool isSugared() const { return true; }
QualType desugar() const { return getCanonicalTypeInternal(); }

static bool classof(const Type *T) {
  return T->getTypeClass() == ObjCTypeParam;
}

void Profile(llvm::FoldingSetNodeID &ID);
static void Profile(llvm::FoldingSetNodeID &ID,
                    const ObjCTypeParamDecl *OTPDecl,
                    QualType CanonicalType,
                    ArrayRef<ObjCProtocolDecl *> protocols);

ObjCTypeParamDecl *getDecl() const { return OTPDecl; }
5788};

5790/// Represents a class type in Objective C.
5791///
5792/// Every Objective C type is a combination of a base type, a set of
5793/// type arguments (optional, for parameterized classes) and a list of
5794/// protocols.
5795///
5796/// Given the following declarations:
5797/// \code
5798///   \@class C<T>;
5799///   \@protocol P;
5800/// \endcode
5801///
5802/// 'C' is an ObjCInterfaceType C.  It is sugar for an ObjCObjectType
5803/// with base C and no protocols.
5804///
5805/// 'C<P>' is an unspecialized ObjCObjectType with base C and protocol list [P].
5806/// 'C<C*>' is a specialized ObjCObjectType with type arguments 'C*' and no
5807/// protocol list.
5808/// 'C<C*><P>' is a specialized ObjCObjectType with base C, type arguments 'C*',
5809/// and protocol list [P].
5810///
5811/// 'id' is a TypedefType which is sugar for an ObjCObjectPointerType whose
5812/// pointee is an ObjCObjectType with base BuiltinType::ObjCIdType
5813/// and no protocols.
5814///
5815/// 'id<P>' is an ObjCObjectPointerType whose pointee is an ObjCObjectType
5816/// with base BuiltinType::ObjCIdType and protocol list [P].  Eventually
5817/// this should get its own sugar class to better represent the source.
5818class ObjCObjectType : public Type,
                     public ObjCProtocolQualifiers<ObjCObjectType> {
friend class ObjCProtocolQualifiers<ObjCObjectType>;

// ObjCObjectType.NumTypeArgs - the number of type arguments stored
// after the ObjCObjectPointerType node.
// ObjCObjectType.NumProtocols - the number of protocols stored
// after the type arguments of ObjCObjectPointerType node.
//
// These protocols are those written directly on the type.  If
// protocol qualifiers ever become additive, the iterators will need
// to get kindof complicated.
//
// In the canonical object type, these are sorted alphabetically
// and uniqued.

/// Either a BuiltinType or an InterfaceType or sugar for either.
QualType BaseType;

/// Cached superclass type.
mutable llvm::PointerIntPair<const ObjCObjectType *, 1, bool>
  CachedSuperClassType;

QualType *getTypeArgStorage();
const QualType *getTypeArgStorage() const {
  return const_cast<ObjCObjectType *>(this)->getTypeArgStorage();
}

ObjCProtocolDecl **getProtocolStorageImpl();
/// Return the number of qualifying protocols in this interface type,
/// or 0 if there are none.
unsigned getNumProtocolsImpl() const {
  return ObjCObjectTypeBits.NumProtocols;
}
void setNumProtocolsImpl(unsigned N) {
  ObjCObjectTypeBits.NumProtocols = N;
}

5856protected:
enum Nonce_ObjCInterface { Nonce_ObjCInterface };

ObjCObjectType(QualType Canonical, QualType Base,
               ArrayRef<QualType> typeArgs,
               ArrayRef<ObjCProtocolDecl *> protocols,
               bool isKindOf);

ObjCObjectType(enum Nonce_ObjCInterface)
    : Type(ObjCInterface, QualType(), TypeDependence::None),
      BaseType(QualType(this_(), 0)) {
  ObjCObjectTypeBits.NumProtocols = 0;
  ObjCObjectTypeBits.NumTypeArgs = 0;
  ObjCObjectTypeBits.IsKindOf = 0;
}

void computeSuperClassTypeSlow() const;

5874public:
/// Gets the base type of this object type.  This is always (possibly
/// sugar for) one of:
///  - the 'id' builtin type (as opposed to the 'id' type visible to the
///    user, which is a typedef for an ObjCObjectPointerType)
///  - the 'Class' builtin type (same caveat)
///  - an ObjCObjectType (currently always an ObjCInterfaceType)
QualType getBaseType() const { return BaseType; }

bool isObjCId() const {
  return getBaseType()->isSpecificBuiltinType(BuiltinType::ObjCId);
}

bool isObjCClass() const {
  return getBaseType()->isSpecificBuiltinType(BuiltinType::ObjCClass);
}

bool isObjCUnqualifiedId() const { return qual_empty() && isObjCId(); }
bool isObjCUnqualifiedClass() const { return qual_empty() && isObjCClass(); }
bool isObjCUnqualifiedIdOrClass() const {
  if (!qual_empty()) return false;
  if (const BuiltinType *T = getBaseType()->getAs<BuiltinType>())
    return T->getKind() == BuiltinType::ObjCId ||
           T->getKind() == BuiltinType::ObjCClass;
  return false;
}
bool isObjCQualifiedId() const { return !qual_empty() && isObjCId(); }
bool isObjCQualifiedClass() const { return !qual_empty() && isObjCClass(); }

/// Gets the interface declaration for this object type, if the base type
/// really is an interface.
ObjCInterfaceDecl *getInterface() const;

/// Determine whether this object type is "specialized", meaning
/// that it has type arguments.
bool isSpecialized() const;

/// Determine whether this object type was written with type arguments.
bool isSpecializedAsWritten() const {
  return ObjCObjectTypeBits.NumTypeArgs > 0;
}

/// Determine whether this object type is "unspecialized", meaning
/// that it has no type arguments.
bool isUnspecialized() const { return !isSpecialized(); }

/// Determine whether this object type is "unspecialized" as
/// written, meaning that it has no type arguments.
bool isUnspecializedAsWritten() const { return !isSpecializedAsWritten(); }

/// Retrieve the type arguments of this object type (semantically).
ArrayRef<QualType> getTypeArgs() const;

/// Retrieve the type arguments of this object type as they were
/// written.
ArrayRef<QualType> getTypeArgsAsWritten() const {
  return llvm::makeArrayRef(getTypeArgStorage(),
                            ObjCObjectTypeBits.NumTypeArgs);
}

/// Whether this is a "__kindof" type as written.
bool isKindOfTypeAsWritten() const { return ObjCObjectTypeBits.IsKindOf; }

/// Whether this ia a "__kindof" type (semantically).
bool isKindOfType() const;

/// Retrieve the type of the superclass of this object type.
///
/// This operation substitutes any type arguments into the
/// superclass of the current class type, potentially producing a
/// specialization of the superclass type. Produces a null type if
/// there is no superclass.
QualType getSuperClassType() const {
  if (!CachedSuperClassType.getInt())
    computeSuperClassTypeSlow();

  assert(CachedSuperClassType.getInt() && "Superclass not set?")((void)0);
  return QualType(CachedSuperClassType.getPointer(), 0);
}

/// Strip off the Objective-C "kindof" type and (with it) any
/// protocol qualifiers.
QualType stripObjCKindOfTypeAndQuals(const ASTContext &ctx) const;

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

static bool classof(const Type *T) {
  return T->getTypeClass() == ObjCObject ||
         T->getTypeClass() == ObjCInterface;
}
5965};

5967/// A class providing a concrete implementation
5968/// of ObjCObjectType, so as to not increase the footprint of
5969/// ObjCInterfaceType.  Code outside of ASTContext and the core type
5970/// system should not reference this type.
5971class ObjCObjectTypeImpl : public ObjCObjectType, public llvm::FoldingSetNode {
friend class ASTContext;

// If anyone adds fields here, ObjCObjectType::getProtocolStorage()
// will need to be modified.

ObjCObjectTypeImpl(QualType Canonical, QualType Base,
                   ArrayRef<QualType> typeArgs,
                   ArrayRef<ObjCProtocolDecl *> protocols,
                   bool isKindOf)
    : ObjCObjectType(Canonical, Base, typeArgs, protocols, isKindOf) {}

5983public:
void Profile(llvm::FoldingSetNodeID &ID);
static void Profile(llvm::FoldingSetNodeID &ID,
                    QualType Base,
                    ArrayRef<QualType> typeArgs,
                    ArrayRef<ObjCProtocolDecl *> protocols,
                    bool isKindOf);
5990};

5992inline QualType *ObjCObjectType::getTypeArgStorage() {
return reinterpret_cast<QualType *>(static_cast<ObjCObjectTypeImpl*>(this)+1);
5994}

5996inline ObjCProtocolDecl **ObjCObjectType::getProtocolStorageImpl() {
  return reinterpret_cast<ObjCProtocolDecl**>(
           getTypeArgStorage() + ObjCObjectTypeBits.NumTypeArgs);
5999}

6001inline ObjCProtocolDecl **ObjCTypeParamType::getProtocolStorageImpl() {
  return reinterpret_cast<ObjCProtocolDecl**>(
           static_cast<ObjCTypeParamType*>(this)+1);
6004}

6006/// Interfaces are the core concept in Objective-C for object oriented design.
6007/// They basically correspond to C++ classes.  There are two kinds of interface
6008/// types: normal interfaces like `NSString`, and qualified interfaces, which
6009/// are qualified with a protocol list like `NSString<NSCopyable, NSAmazing>`.
6010///
6011/// ObjCInterfaceType guarantees the following properties when considered
6012/// as a subtype of its superclass, ObjCObjectType:
6013///   - There are no protocol qualifiers.  To reinforce this, code which
6014///     tries to invoke the protocol methods via an ObjCInterfaceType will
6015///     fail to compile.
6016///   - It is its own base type.  That is, if T is an ObjCInterfaceType*,
6017///     T->getBaseType() == QualType(T, 0).
6018class ObjCInterfaceType : public ObjCObjectType {
friend class ASTContext; // ASTContext creates these.
friend class ASTReader;
friend class ObjCInterfaceDecl;
template <class T> friend class serialization::AbstractTypeReader;

mutable ObjCInterfaceDecl *Decl;

ObjCInterfaceType(const ObjCInterfaceDecl *D)
    : ObjCObjectType(Nonce_ObjCInterface),
      Decl(const_cast<ObjCInterfaceDecl*>(D)) {}

6030public:
/// Get the declaration of this interface.
ObjCInterfaceDecl *getDecl() const { return Decl; }

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

static bool classof(const Type *T) {
  return T->getTypeClass() == ObjCInterface;
}

// Nonsense to "hide" certain members of ObjCObjectType within this
// class.  People asking for protocols on an ObjCInterfaceType are
// not going to get what they want: ObjCInterfaceTypes are
// guaranteed to have no protocols.
enum {
  qual_iterator,
  qual_begin,
  qual_end,
  getNumProtocols,
  getProtocol
};
6052};

6054inline ObjCInterfaceDecl *ObjCObjectType::getInterface() const {
QualType baseType = getBaseType();
while (const auto *ObjT = baseType->getAs<ObjCObjectType>()) {
  if (const auto *T = dyn_cast<ObjCInterfaceType>(ObjT))
    return T->getDecl();

  baseType = ObjT->getBaseType();
}

return nullptr;
6064}

6066/// Represents a pointer to an Objective C object.
6067///
6068/// These are constructed from pointer declarators when the pointee type is
6069/// an ObjCObjectType (or sugar for one).  In addition, the 'id' and 'Class'
6070/// types are typedefs for these, and the protocol-qualified types 'id<P>'
6071/// and 'Class<P>' are translated into these.
6072///
6073/// Pointers to pointers to Objective C objects are still PointerTypes;
6074/// only the first level of pointer gets it own type implementation.
6075class ObjCObjectPointerType : public Type, public llvm::FoldingSetNode {
friend class ASTContext; // ASTContext creates these.

QualType PointeeType;

ObjCObjectPointerType(QualType Canonical, QualType Pointee)
    : Type(ObjCObjectPointer, Canonical, Pointee->getDependence()),
      PointeeType(Pointee) {}

6084public:
/// Gets the type pointed to by this ObjC pointer.
/// The result will always be an ObjCObjectType or sugar thereof.
QualType getPointeeType() const { return PointeeType; }

/// Gets the type pointed to by this ObjC pointer.  Always returns non-null.
///
/// This method is equivalent to getPointeeType() except that
/// it discards any typedefs (or other sugar) between this
/// type and the "outermost" object type.  So for:
/// \code
///   \@class A; \@protocol P; \@protocol Q;
///   typedef A<P> AP;
///   typedef A A1;
///   typedef A1<P> A1P;
///   typedef A1P<Q> A1PQ;
/// \endcode
/// For 'A*', getObjectType() will return 'A'.
/// For 'A<P>*', getObjectType() will return 'A<P>'.
/// For 'AP*', getObjectType() will return 'A<P>'.
/// For 'A1*', getObjectType() will return 'A'.
/// For 'A1<P>*', getObjectType() will return 'A1<P>'.
/// For 'A1P*', getObjectType() will return 'A1<P>'.
/// For 'A1PQ*', getObjectType() will return 'A1<Q>', because
///   adding protocols to a protocol-qualified base discards the
///   old qualifiers (for now).  But if it didn't, getObjectType()
///   would return 'A1P<Q>' (and we'd have to make iterating over
///   qualifiers more complicated).
const ObjCObjectType *getObjectType() const {
  return PointeeType->castAs<ObjCObjectType>();
}

/// If this pointer points to an Objective C
/// \@interface type, gets the type for that interface.  Any protocol
/// qualifiers on the interface are ignored.
///
/// \return null if the base type for this pointer is 'id' or 'Class'
const ObjCInterfaceType *getInterfaceType() const;

/// If this pointer points to an Objective \@interface
/// type, gets the declaration for that interface.
///
/// \return null if the base type for this pointer is 'id' or 'Class'
ObjCInterfaceDecl *getInterfaceDecl() const {
  return getObjectType()->getInterface();
}

/// True if this is equivalent to the 'id' type, i.e. if
/// its object type is the primitive 'id' type with no protocols.
bool isObjCIdType() const {
  return getObjectType()->isObjCUnqualifiedId();
}

/// True if this is equivalent to the 'Class' type,
/// i.e. if its object tive is the primitive 'Class' type with no protocols.
bool isObjCClassType() const {
  return getObjectType()->isObjCUnqualifiedClass();
}

/// True if this is equivalent to the 'id' or 'Class' type,
bool isObjCIdOrClassType() const {
  return getObjectType()->isObjCUnqualifiedIdOrClass();
}

/// True if this is equivalent to 'id<P>' for some non-empty set of
/// protocols.
bool isObjCQualifiedIdType() const {
  return getObjectType()->isObjCQualifiedId();
}

/// True if this is equivalent to 'Class<P>' for some non-empty set of
/// protocols.
bool isObjCQualifiedClassType() const {
  return getObjectType()->isObjCQualifiedClass();
}

/// Whether this is a "__kindof" type.
bool isKindOfType() const { return getObjectType()->isKindOfType(); }

/// Whether this type is specialized, meaning that it has type arguments.
bool isSpecialized() const { return getObjectType()->isSpecialized(); }

/// Whether this type is specialized, meaning that it has type arguments.
bool isSpecializedAsWritten() const {
  return getObjectType()->isSpecializedAsWritten();
}

/// Whether this type is unspecialized, meaning that is has no type arguments.
bool isUnspecialized() const { return getObjectType()->isUnspecialized(); }

/// Determine whether this object type is "unspecialized" as
/// written, meaning that it has no type arguments.
bool isUnspecializedAsWritten() const { return !isSpecializedAsWritten(); }

/// Retrieve the type arguments for this type.
ArrayRef<QualType> getTypeArgs() const {
  return getObjectType()->getTypeArgs();
}

/// Retrieve the type arguments for this type.
ArrayRef<QualType> getTypeArgsAsWritten() const {
  return getObjectType()->getTypeArgsAsWritten();
}

/// An iterator over the qualifiers on the object type.  Provided
/// for convenience.  This will always iterate over the full set of
/// protocols on a type, not just those provided directly.
using qual_iterator = ObjCObjectType::qual_iterator;
using qual_range = llvm::iterator_range<qual_iterator>;

qual_range quals() const { return qual_range(qual_begin(), qual_end()); }

qual_iterator qual_begin() const {
  return getObjectType()->qual_begin();
}

qual_iterator qual_end() const {
  return getObjectType()->qual_end();
}

bool qual_empty() const { return getObjectType()->qual_empty(); }

/// Return the number of qualifying protocols on the object type.
unsigned getNumProtocols() const {
  return getObjectType()->getNumProtocols();
}

/// Retrieve a qualifying protocol by index on the object type.
ObjCProtocolDecl *getProtocol(unsigned I) const {
  return getObjectType()->getProtocol(I);
}

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

/// Retrieve the type of the superclass of this object pointer type.
///
/// This operation substitutes any type arguments into the
/// superclass of the current class type, potentially producing a
/// pointer to a specialization of the superclass type. Produces a
/// null type if there is no superclass.
QualType getSuperClassType() const;

/// Strip off the Objective-C "kindof" type and (with it) any
/// protocol qualifiers.
const ObjCObjectPointerType *stripObjCKindOfTypeAndQuals(
                               const ASTContext &ctx) const;

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, getPointeeType());
}

static void Profile(llvm::FoldingSetNodeID &ID, QualType T) {
  ID.AddPointer(T.getAsOpaquePtr());
}

static bool classof(const Type *T) {
  return T->getTypeClass() == ObjCObjectPointer;
}
6243};

6245class AtomicType : public Type, public llvm::FoldingSetNode {
friend class ASTContext; // ASTContext creates these.

QualType ValueType;

AtomicType(QualType ValTy, QualType Canonical)
    : Type(Atomic, Canonical, ValTy->getDependence()), ValueType(ValTy) {}

6253public:
/// Gets the type contained by this atomic type, i.e.
/// the type returned by performing an atomic load of this atomic type.
QualType getValueType() const { return ValueType; }

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, getValueType());
}

static void Profile(llvm::FoldingSetNodeID &ID, QualType T) {
  ID.AddPointer(T.getAsOpaquePtr());
}

static bool classof(const Type *T) {
  return T->getTypeClass() == Atomic;
}
6272};

6274/// PipeType - OpenCL20.
6275class PipeType : public Type, public llvm::FoldingSetNode {
friend class ASTContext; // ASTContext creates these.

QualType ElementType;
bool isRead;

PipeType(QualType elemType, QualType CanonicalPtr, bool isRead)
    : Type(Pipe, CanonicalPtr, elemType->getDependence()),
      ElementType(elemType), isRead(isRead) {}

6285public:
QualType getElementType() const { return ElementType; }

bool isSugared() const { return false; }

QualType desugar() const { return QualType(this, 0); }

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, getElementType(), isReadOnly());
}

static void Profile(llvm::FoldingSetNodeID &ID, QualType T, bool isRead) {
  ID.AddPointer(T.getAsOpaquePtr());
  ID.AddBoolean(isRead);
}

static bool classof(const Type *T) {
  return T->getTypeClass() == Pipe;
}

bool isReadOnly() const { return isRead; }
6306};

6308/// A fixed int type of a specified bitwidth.
6309class ExtIntType final : public Type, public llvm::FoldingSetNode {
friend class ASTContext;
unsigned IsUnsigned : 1;
unsigned NumBits : 24;

6314protected:
ExtIntType(bool isUnsigned, unsigned NumBits);

6317public:
bool isUnsigned() const { return IsUnsigned; }
bool isSigned() const { return !IsUnsigned; }
unsigned getNumBits() const { return NumBits; }

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, isUnsigned(), getNumBits());
}

static void Profile(llvm::FoldingSetNodeID &ID, bool IsUnsigned,
                    unsigned NumBits) {
  ID.AddBoolean(IsUnsigned);
  ID.AddInteger(NumBits);
}

static bool classof(const Type *T) { return T->getTypeClass() == ExtInt; }
6336};

6338class DependentExtIntType final : public Type, public llvm::FoldingSetNode {
friend class ASTContext;
const ASTContext &Context;
llvm::PointerIntPair<Expr*, 1, bool> ExprAndUnsigned;

6343protected:
DependentExtIntType(const ASTContext &Context, bool IsUnsigned,
                    Expr *NumBits);

6347public:
bool isUnsigned() const;
bool isSigned() const { return !isUnsigned(); }
Expr *getNumBitsExpr() const;

bool isSugared() const { return false; }
QualType desugar() const { return QualType(this, 0); }

void Profile(llvm::FoldingSetNodeID &ID) {
  Profile(ID, Context, isUnsigned(), getNumBitsExpr());
}
static void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
                    bool IsUnsigned, Expr *NumBitsExpr);

static bool classof(const Type *T) {
  return T->getTypeClass() == DependentExtInt;
}
6364};

6366/// A qualifier set is used to build a set of qualifiers.
6367class QualifierCollector : public Qualifiers {
6368public:
QualifierCollector(Qualifiers Qs = Qualifiers()) : Qualifiers(Qs) {}

/// Collect any qualifiers on the given type and return an
/// unqualified type.  The qualifiers are assumed to be consistent
/// with those already in the type.
const Type *strip(QualType type) {
  addFastQualifiers(type.getLocalFastQualifiers());
  if (!type.hasLocalNonFastQualifiers())
    return type.getTypePtrUnsafe();

  const ExtQuals *extQuals = type.getExtQualsUnsafe();
  addConsistentQualifiers(extQuals->getQualifiers());
  return extQuals->getBaseType();
}

/// Apply the collected qualifiers to the given type.
QualType apply(const ASTContext &Context, QualType QT) const;

/// Apply the collected qualifiers to the given type.
QualType apply(const ASTContext &Context, const Type* T) const;
6389};

6391/// A container of type source information.
6392///
6393/// A client can read the relevant info using TypeLoc wrappers, e.g:
6394/// @code
6395/// TypeLoc TL = TypeSourceInfo->getTypeLoc();
6396/// TL.getBeginLoc().print(OS, SrcMgr);
6397/// @endcode
6398class alignas(8) TypeSourceInfo {
// Contains a memory block after the class, used for type source information,
// allocated by ASTContext.
friend class ASTContext;

QualType Ty;

TypeSourceInfo(QualType ty) : Ty(ty) {}

6407public:
/// Return the type wrapped by this type source info.
QualType getType() const { return Ty; }

/// Return the TypeLoc wrapper for the type source info.
TypeLoc getTypeLoc() const; // implemented in TypeLoc.h

/// Override the type stored in this TypeSourceInfo. Use with caution!
void overrideType(QualType T) { Ty = T; }
6416};

6418// Inline function definitions.

6420inline SplitQualType SplitQualType::getSingleStepDesugaredType() const {
SplitQualType desugar =
  Ty->getLocallyUnqualifiedSingleStepDesugaredType().split();
desugar.Quals.addConsistentQualifiers(Quals);
return desugar;
6425}

6427inline const Type *QualType::getTypePtr() const {
return getCommonPtr()->BaseType;
6429}

6431inline const Type *QualType::getTypePtrOrNull() const {
return (isNull() ? nullptr : getCommonPtr()->BaseType);
6433}

6435inline SplitQualType QualType::split() const {
if (!hasLocalNonFastQualifiers())
  return SplitQualType(getTypePtrUnsafe(),
                       Qualifiers::fromFastMask(getLocalFastQualifiers()));

const ExtQuals *eq = getExtQualsUnsafe();
Qualifiers qs = eq->getQualifiers();
qs.addFastQualifiers(getLocalFastQualifiers());
return SplitQualType(eq->getBaseType(), qs);
6444}

6446inline Qualifiers QualType::getLocalQualifiers() const {
Qualifiers Quals;
if (hasLocalNonFastQualifiers())
  Quals = getExtQualsUnsafe()->getQualifiers();
Quals.addFastQualifiers(getLocalFastQualifiers());
return Quals;
6452}

6454inline Qualifiers QualType::getQualifiers() const {
Qualifiers quals = getCommonPtr()->CanonicalType.getLocalQualifiers();
quals.addFastQualifiers(getLocalFastQualifiers());
return quals;
6458}

6460inline unsigned QualType::getCVRQualifiers() const {
unsigned cvr = getCommonPtr()->CanonicalType.getLocalCVRQualifiers();
cvr |= getLocalCVRQualifiers();
return cvr;
6464}

6466inline QualType QualType::getCanonicalType() const {
QualType canon = getCommonPtr()->CanonicalType;
return canon.withFastQualifiers(getLocalFastQualifiers());
6469}

6471inline bool QualType::isCanonical() const {
return getTypePtr()->isCanonicalUnqualified();
6473}

6475inline bool QualType::isCanonicalAsParam() const {
if (!isCanonical()) return false;
if (hasLocalQualifiers()) return false;

const Type *T = getTypePtr();
if (T->isVariablyModifiedType() && T->hasSizedVLAType())
  return false;

return !isa<FunctionType>(T) && !isa<ArrayType>(T);
6484}

6486inline bool QualType::isConstQualified() const {
return isLocalConstQualified() ||
       getCommonPtr()->CanonicalType.isLocalConstQualified();
6489}

6491inline bool QualType::isRestrictQualified() const {
return isLocalRestrictQualified() ||
       getCommonPtr()->CanonicalType.isLocalRestrictQualified();
6494}


6497inline bool QualType::isVolatileQualified() const {
return isLocalVolatileQualified() ||
       getCommonPtr()->CanonicalType.isLocalVolatileQualified();
6500}

6502inline bool QualType::hasQualifiers() const {
return hasLocalQualifiers() ||
       getCommonPtr()->CanonicalType.hasLocalQualifiers();
6505}

6507inline QualType QualType::getUnqualifiedType() const {
if (!getTypePtr()->getCanonicalTypeInternal().hasLocalQualifiers())
  return QualType(getTypePtr(), 0);

return QualType(getSplitUnqualifiedTypeImpl(*this).Ty, 0);
6512}

6514inline SplitQualType QualType::getSplitUnqualifiedType() const {
if (!getTypePtr()->getCanonicalTypeInternal().hasLocalQualifiers())
  return split();

return getSplitUnqualifiedTypeImpl(*this);
6519}

6521inline void QualType::removeLocalConst() {
removeLocalFastQualifiers(Qualifiers::Const);
6523}

6525inline void QualType::removeLocalRestrict() {
removeLocalFastQualifiers(Qualifiers::Restrict);
6527}

6529inline void QualType::removeLocalVolatile() {
removeLocalFastQualifiers(Qualifiers::Volatile);
6531}

6533inline void QualType::removeLocalCVRQualifiers(unsigned Mask) {
assert(!(Mask & ~Qualifiers::CVRMask) && "mask has non-CVR bits")((void)0);
static_assert((int)Qualifiers::CVRMask == (int)Qualifiers::FastMask,
              "Fast bits differ from CVR bits!");

// Fast path: we don't need to touch the slow qualifiers.
removeLocalFastQualifiers(Mask);
6540}

6542/// Check if this type has any address space qualifier.
6543inline bool QualType::hasAddressSpace() const {
return getQualifiers().hasAddressSpace();
6545}

6547/// Return the address space of this type.
6548inline LangAS QualType::getAddressSpace() const {
return getQualifiers().getAddressSpace();
6550}

6552/// Return the gc attribute of this type.
6553inline Qualifiers::GC QualType::getObjCGCAttr() const {
return getQualifiers().getObjCGCAttr();
6555}

6557inline bool QualType::hasNonTrivialToPrimitiveDefaultInitializeCUnion() const {
if (auto *RD = getTypePtr()->getBaseElementTypeUnsafe()->getAsRecordDecl())
  return hasNonTrivialToPrimitiveDefaultInitializeCUnion(RD);
return false;
6561}

6563inline bool QualType::hasNonTrivialToPrimitiveDestructCUnion() const {
if (auto *RD = getTypePtr()->getBaseElementTypeUnsafe()->getAsRecordDecl())
  return hasNonTrivialToPrimitiveDestructCUnion(RD);
return false;
6567}

6569inline bool QualType::hasNonTrivialToPrimitiveCopyCUnion() const {
if (auto *RD = getTypePtr()->getBaseElementTypeUnsafe()->getAsRecordDecl())
  return hasNonTrivialToPrimitiveCopyCUnion(RD);
return false;
6573}

6575inline FunctionType::ExtInfo getFunctionExtInfo(const Type &t) {
if (const auto *PT = t.getAs<PointerType>()) {
  if (const auto *FT = PT->getPointeeType()->getAs<FunctionType>())
    return FT->getExtInfo();
} else if (const auto *FT = t.getAs<FunctionType>())
  return FT->getExtInfo();

return FunctionType::ExtInfo();
6583}

6585inline FunctionType::ExtInfo getFunctionExtInfo(QualType t) {
return getFunctionExtInfo(*t);
6587}

6589/// Determine whether this type is more
6590/// qualified than the Other type. For example, "const volatile int"
6591/// is more qualified than "const int", "volatile int", and
6592/// "int". However, it is not more qualified than "const volatile
6593/// int".
6594inline bool QualType::isMoreQualifiedThan(QualType other) const {
Qualifiers MyQuals = getQualifiers();
Qualifiers OtherQuals = other.getQualifiers();
return (MyQuals != OtherQuals && MyQuals.compatiblyIncludes(OtherQuals));
6598}

6600/// Determine whether this type is at last
6601/// as qualified as the Other type. For example, "const volatile
6602/// int" is at least as qualified as "const int", "volatile int",
6603/// "int", and "const volatile int".
6604inline bool QualType::isAtLeastAsQualifiedAs(QualType other) const {
Qualifiers OtherQuals = other.getQualifiers();

// Ignore __unaligned qualifier if this type is a void.
if (getUnqualifiedType()->isVoidType())
  OtherQuals.removeUnaligned();

return getQualifiers().compatiblyIncludes(OtherQuals);
6612}

6614/// If Type is a reference type (e.g., const
6615/// int&), returns the type that the reference refers to ("const
6616/// int"). Otherwise, returns the type itself. This routine is used
6617/// throughout Sema to implement C++ 5p6:
6618///
6619///   If an expression initially has the type "reference to T" (8.3.2,
6620///   8.5.3), the type is adjusted to "T" prior to any further
6621///   analysis, the expression designates the object or function
6622///   denoted by the reference, and the expression is an lvalue.
6623inline QualType QualType::getNonReferenceType() const {
if (const auto *RefType = (*this)->getAs<ReferenceType>())
  return RefType->getPointeeType();
else
  return *this;
6628}

6630inline bool QualType::isCForbiddenLValueType() const {
return ((getTypePtr()->isVoidType() && !hasQualifiers()) ||
        getTypePtr()->isFunctionType());
6633}

6635/// Tests whether the type is categorized as a fundamental type.
6636///
6637/// \returns True for types specified in C++0x [basic.fundamental].
6638inline bool Type::isFundamentalType() const {
return isVoidType() ||
       isNullPtrType() ||
       // FIXME: It's really annoying that we don't have an
       // 'isArithmeticType()' which agrees with the standard definition.
       (isArithmeticType() && !isEnumeralType());
6644}

6646/// Tests whether the type is categorized as a compound type.
6647///
6648/// \returns True for types specified in C++0x [basic.compound].
6649inline bool Type::isCompoundType() const {
// C++0x [basic.compound]p1:
//   Compound types can be constructed in the following ways:
//    -- arrays of objects of a given type [...];
return isArrayType() ||
//    -- functions, which have parameters of given types [...];
       isFunctionType() ||
//    -- pointers to void or objects or functions [...];
       isPointerType() ||
//    -- references to objects or functions of a given type. [...]
       isReferenceType() ||
//    -- classes containing a sequence of objects of various types, [...];
       isRecordType() ||
//    -- unions, which are classes capable of containing objects of different
//               types at different times;
       isUnionType() ||
//    -- enumerations, which comprise a set of named constant values. [...];
       isEnumeralType() ||
//    -- pointers to non-static class members, [...].
       isMemberPointerType();
6669}

6671inline bool Type::isFunctionType() const {
return isa<FunctionType>(CanonicalType);
6673}

6675inline bool Type::isPointerType() const {
return isa<PointerType>(CanonicalType);
6677}

6679inline bool Type::isAnyPointerType() const {
return isPointerType() || isObjCObjectPointerType();
6681}

6683inline bool Type::isBlockPointerType() const {
return isa<BlockPointerType>(CanonicalType);
6685}

6687inline bool Type::isReferenceType() const {
return isa<ReferenceType>(CanonicalType);
6689}

6691inline bool Type::isLValueReferenceType() const {
return isa<LValueReferenceType>(CanonicalType);
6693}

6695inline bool Type::isRValueReferenceType() const {
return isa<RValueReferenceType>(CanonicalType);
6697}

6699inline bool Type::isObjectPointerType() const {
// Note: an "object pointer type" is not the same thing as a pointer to an
// object type; rather, it is a pointer to an object type or a pointer to cv
// void.
if (const auto *T = getAs<PointerType>())
  return !T->getPointeeType()->isFunctionType();
else
  return false;
6707}

6709inline bool Type::isFunctionPointerType() const {
if (const auto *T = getAs<PointerType>())
  return T->getPointeeType()->isFunctionType();
else
  return false;
6714}

6716inline bool Type::isFunctionReferenceType() const {
if (const auto *T = getAs<ReferenceType>())
  return T->getPointeeType()->isFunctionType();
else
  return false;
6721}

6723inline bool Type::isMemberPointerType() const {
return isa<MemberPointerType>(CanonicalType);
6725}

6727inline bool Type::isMemberFunctionPointerType() const {
if (const auto *T = getAs<MemberPointerType>())
  return T->isMemberFunctionPointer();
else
  return false;
6732}

6734inline bool Type::isMemberDataPointerType() const {
if (const auto *T = getAs<MemberPointerType>())
  return T->isMemberDataPointer();
else
  return false;
6739}

6741inline bool Type::isArrayType() const {
return isa<ArrayType>(CanonicalType);
6743}

6745inline bool Type::isConstantArrayType() const {
return isa<ConstantArrayType>(CanonicalType);
6747}

6749inline bool Type::isIncompleteArrayType() const {
return isa<IncompleteArrayType>(CanonicalType);
6751}

6753inline bool Type::isVariableArrayType() const {
return isa<VariableArrayType>(CanonicalType);
6755}

6757inline bool Type::isDependentSizedArrayType() const {
return isa<DependentSizedArrayType>(CanonicalType);
6759}

6761inline bool Type::isBuiltinType() const {
return isa<BuiltinType>(CanonicalType);
6763}

6765inline bool Type::isRecordType() const {
return isa<RecordType>(CanonicalType);
6767}

6769inline bool Type::isEnumeralType() const {
return isa<EnumType>(CanonicalType);
22
←
Assuming field 'CanonicalType' is a 'EnumType'→
23
←
Returning the value 1, which participates in a condition later→
6771}

6773inline bool Type::isAnyComplexType() const {
return isa<ComplexType>(CanonicalType);
6775}

6777inline bool Type::isVectorType() const {
return isa<VectorType>(CanonicalType);
6779}

6781inline bool Type::isExtVectorType() const {
return isa<ExtVectorType>(CanonicalType);
6783}

6785inline bool Type::isMatrixType() const {
return isa<MatrixType>(CanonicalType);
6787}

6789inline bool Type::isConstantMatrixType() const {
return isa<ConstantMatrixType>(CanonicalType);
6791}

6793inline bool Type::isDependentAddressSpaceType() const {
return isa<DependentAddressSpaceType>(CanonicalType);
6795}

6797inline bool Type::isObjCObjectPointerType() const {
return isa<ObjCObjectPointerType>(CanonicalType);
6799}

6801inline bool Type::isObjCObjectType() const {
return isa<ObjCObjectType>(CanonicalType);
6803}

6805inline bool Type::isObjCObjectOrInterfaceType() const {
return isa<ObjCInterfaceType>(CanonicalType) ||
  isa<ObjCObjectType>(CanonicalType);
6808}

6810inline bool Type::isAtomicType() const {
return isa<AtomicType>(CanonicalType);
6812}

6814inline bool Type::isUndeducedAutoType() const {
return isa<AutoType>(CanonicalType);
6816}

6818inline bool Type::isObjCQualifiedIdType() const {
if (const auto *OPT = getAs<ObjCObjectPointerType>())
  return OPT->isObjCQualifiedIdType();
return false;
6822}

6824inline bool Type::isObjCQualifiedClassType() const {
if (const auto *OPT = getAs<ObjCObjectPointerType>())
  return OPT->isObjCQualifiedClassType();
return false;
6828}

6830inline bool Type::isObjCIdType() const {
if (const auto *OPT = getAs<ObjCObjectPointerType>())
  return OPT->isObjCIdType();
return false;
6834}

6836inline bool Type::isObjCClassType() const {
if (const auto *OPT = getAs<ObjCObjectPointerType>())
  return OPT->isObjCClassType();
return false;
6840}

6842inline bool Type::isObjCSelType() const {
if (const auto *OPT = getAs<PointerType>())
  return OPT->getPointeeType()->isSpecificBuiltinType(BuiltinType::ObjCSel);
return false;
6846}

6848inline bool Type::isObjCBuiltinType() const {
return isObjCIdType() || isObjCClassType() || isObjCSelType();
6850}

6852inline bool Type::isDecltypeType() const {
return isa<DecltypeType>(this);
6854}

6856#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
inline bool Type::is##Id##Type() const { \
  return isSpecificBuiltinType(BuiltinType::Id); \
}
6860#include "clang/Basic/OpenCLImageTypes.def"

6862inline bool Type::isSamplerT() const {
return isSpecificBuiltinType(BuiltinType::OCLSampler);
6864}

6866inline bool Type::isEventT() const {
return isSpecificBuiltinType(BuiltinType::OCLEvent);
6868}

6870inline bool Type::isClkEventT() const {
return isSpecificBuiltinType(BuiltinType::OCLClkEvent);
6872}

6874inline bool Type::isQueueT() const {
return isSpecificBuiltinType(BuiltinType::OCLQueue);
6876}

6878inline bool Type::isReserveIDT() const {
return isSpecificBuiltinType(BuiltinType::OCLReserveID);
6880}

6882inline bool Type::isImageType() const {
6883#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) is##Id##Type() ||
return
6885#include "clang/Basic/OpenCLImageTypes.def"
    false; // end boolean or operation
6887}

6889inline bool Type::isPipeType() const {
return isa<PipeType>(CanonicalType);
6891}

6893inline bool Type::isExtIntType() const {
return isa<ExtIntType>(CanonicalType);
34
←
Assuming field 'CanonicalType' is a 'ExtIntType'→
35
←
Returning the value 1, which participates in a condition later→
6895}

6897#define EXT_OPAQUE_TYPE(ExtType, Id, Ext) \
inline bool Type::is##Id##Type() const { \
  return isSpecificBuiltinType(BuiltinType::Id); \
}
6901#include "clang/Basic/OpenCLExtensionTypes.def"

6903inline bool Type::isOCLIntelSubgroupAVCType() const {
6904#define INTEL_SUBGROUP_AVC_TYPE(ExtType, Id) \
isOCLIntelSubgroupAVC##Id##Type() ||
return
6907#include "clang/Basic/OpenCLExtensionTypes.def"
  false; // end of boolean or operation
6909}

6911inline bool Type::isOCLExtOpaqueType() const {
6912#define EXT_OPAQUE_TYPE(ExtType, Id, Ext) is##Id##Type() ||
return
6914#include "clang/Basic/OpenCLExtensionTypes.def"
  false; // end of boolean or operation
6916}

6918inline bool Type::isOpenCLSpecificType() const {
return isSamplerT() || isEventT() || isImageType() || isClkEventT() ||
       isQueueT() || isReserveIDT() || isPipeType() || isOCLExtOpaqueType();
6921}

6923inline bool Type::isTemplateTypeParmType() const {
return isa<TemplateTypeParmType>(CanonicalType);
6925}

6927inline bool Type::isSpecificBuiltinType(unsigned K) const {
if (const BuiltinType *BT = getAs<BuiltinType>()) {
  return BT->getKind() == static_cast<BuiltinType::Kind>(K);
}
return false;
6932}

6934inline bool Type::isPlaceholderType() const {
if (const auto *BT = dyn_cast<BuiltinType>(this))
  return BT->isPlaceholderType();
return false;
6938}

6940inline const BuiltinType *Type::getAsPlaceholderType() const {
if (const auto *BT = dyn_cast<BuiltinType>(this))
  if (BT->isPlaceholderType())
    return BT;
return nullptr;
6945}

6947inline bool Type::isSpecificPlaceholderType(unsigned K) const {
assert(BuiltinType::isPlaceholderTypeKind((BuiltinType::Kind) K))((void)0);
return isSpecificBuiltinType(K);
6950}

6952inline bool Type::isNonOverloadPlaceholderType() const {
if (const auto *BT = dyn_cast<BuiltinType>(this))
  return BT->isNonOverloadPlaceholderType();
return false;
6956}

6958inline bool Type::isVoidType() const {
return isSpecificBuiltinType(BuiltinType::Void);
6960}

6962inline bool Type::isHalfType() const {
// FIXME: Should we allow complex __fp16? Probably not.
return isSpecificBuiltinType(BuiltinType::Half);
6965}

6967inline bool Type::isFloat16Type() const {
return isSpecificBuiltinType(BuiltinType::Float16);
6969}

6971inline bool Type::isBFloat16Type() const {
return isSpecificBuiltinType(BuiltinType::BFloat16);
6973}

6975inline bool Type::isFloat128Type() const {
return isSpecificBuiltinType(BuiltinType::Float128);
6977}

6979inline bool Type::isNullPtrType() const {
return isSpecificBuiltinType(BuiltinType::NullPtr);
6981}

6983bool IsEnumDeclComplete(EnumDecl *);
6984bool IsEnumDeclScoped(EnumDecl *);

6986inline bool Type::isIntegerType() const {
if (const auto *BT = dyn_cast<BuiltinType>(CanonicalType))
  return BT->getKind() >= BuiltinType::Bool &&
         BT->getKind() <= BuiltinType::Int128;
if (const EnumType *ET = dyn_cast<EnumType>(CanonicalType)) {
  // Incomplete enum types are not treated as integer types.
  // FIXME: In C++, enum types are never integer types.
  return IsEnumDeclComplete(ET->getDecl()) &&
    !IsEnumDeclScoped(ET->getDecl());
}
return isExtIntType();
6997}

6999inline bool Type::isFixedPointType() const {
if (const auto *BT = dyn_cast<BuiltinType>(CanonicalType)) {
  return BT->getKind() >= BuiltinType::ShortAccum &&
         BT->getKind() <= BuiltinType::SatULongFract;
}
return false;
7005}

7007inline bool Type::isFixedPointOrIntegerType() const {
return isFixedPointType() || isIntegerType();
7009}

7011inline bool Type::isSaturatedFixedPointType() const {
if (const auto *BT = dyn_cast<BuiltinType>(CanonicalType)) {
  return BT->getKind() >= BuiltinType::SatShortAccum &&
         BT->getKind() <= BuiltinType::SatULongFract;
}
return false;
7017}

7019inline bool Type::isUnsaturatedFixedPointType() const {
return isFixedPointType() && !isSaturatedFixedPointType();
7021}

7023inline bool Type::isSignedFixedPointType() const {
if (const auto *BT = dyn_cast<BuiltinType>(CanonicalType)) {
  return ((BT->getKind() >= BuiltinType::ShortAccum &&
           BT->getKind() <= BuiltinType::LongAccum) ||
          (BT->getKind() >= BuiltinType::ShortFract &&
           BT->getKind() <= BuiltinType::LongFract) ||
          (BT->getKind() >= BuiltinType::SatShortAccum &&
           BT->getKind() <= BuiltinType::SatLongAccum) ||
          (BT->getKind() >= BuiltinType::SatShortFract &&
           BT->getKind() <= BuiltinType::SatLongFract));
}
return false;
7035}

7037inline bool Type::isUnsignedFixedPointType() const {
return isFixedPointType() && !isSignedFixedPointType();
7039}

7041inline bool Type::isScalarType() const {
if (const auto *BT = dyn_cast<BuiltinType>(CanonicalType))
  return BT->getKind() > BuiltinType::Void &&
         BT->getKind() <= BuiltinType::NullPtr;
if (const EnumType *ET = dyn_cast<EnumType>(CanonicalType))
  // Enums are scalar types, but only if they are defined.  Incomplete enums
  // are not treated as scalar types.
  return IsEnumDeclComplete(ET->getDecl());
return isa<PointerType>(CanonicalType) ||
       isa<BlockPointerType>(CanonicalType) ||
       isa<MemberPointerType>(CanonicalType) ||
       isa<ComplexType>(CanonicalType) ||
       isa<ObjCObjectPointerType>(CanonicalType) ||
       isExtIntType();
7055}

7057inline bool Type::isIntegralOrEnumerationType() const {
if (const auto *BT = dyn_cast<BuiltinType>(CanonicalType))
29
←
Assuming 'BT' is null→
30
←
Taking false branch→
  return BT->getKind() >= BuiltinType::Bool &&
         BT->getKind() <= BuiltinType::Int128;

// Check for a complete enum type; incomplete enum types are not properly an
// enumeration type in the sense required here.
if (const auto *ET = dyn_cast<EnumType>(CanonicalType))
31
←
Assuming 'ET' is null→
32
←
Taking false branch→
  return IsEnumDeclComplete(ET->getDecl());

return isExtIntType();
33
←
Calling 'Type::isExtIntType'→
36
←
Returning from 'Type::isExtIntType'→
37
←
Returning the value 1, which participates in a condition later→
7068}

7070inline bool Type::isBooleanType() const {
if (const auto *BT = dyn_cast<BuiltinType>(CanonicalType))
  return BT->getKind() == BuiltinType::Bool;
return false;
7074}

7076inline bool Type::isUndeducedType() const {
auto *DT = getContainedDeducedType();
return DT && !DT->isDeduced();
7079}

7081/// Determines whether this is a type for which one can define
7082/// an overloaded operator.
7083inline bool Type::isOverloadableType() const {
return isDependentType() || isRecordType() || isEnumeralType();
7085}

7087/// Determines whether this type is written as a typedef-name.
7088inline bool Type::isTypedefNameType() const {
if (getAs<TypedefType>())
  return true;
if (auto *TST = getAs<TemplateSpecializationType>())
  return TST->isTypeAlias();
return false;
7094}

7096/// Determines whether this type can decay to a pointer type.
7097inline bool Type::canDecayToPointerType() const {
return isFunctionType() || isArrayType();
7099}

7101inline bool Type::hasPointerRepresentation() const {
return (isPointerType() || isReferenceType() || isBlockPointerType() ||
        isObjCObjectPointerType() || isNullPtrType());
7104}

7106inline bool Type::hasObjCPointerRepresentation() const {
return isObjCObjectPointerType();
7108}

7110inline const Type *Type::getBaseElementTypeUnsafe() const {
const Type *type = this;
while (const ArrayType *arrayType = type->getAsArrayTypeUnsafe())
  type = arrayType->getElementType().getTypePtr();
return type;
7115}

7117inline const Type *Type::getPointeeOrArrayElementType() const {
const Type *type = this;
if (type->isAnyPointerType())
  return type->getPointeeType().getTypePtr();
else if (type->isArrayType())
  return type->getBaseElementTypeUnsafe();
return type;
7124}
7125/// Insertion operator for partial diagnostics. This allows sending adress
7126/// spaces into a diagnostic with <<.
7127inline const StreamingDiagnostic &operator<<(const StreamingDiagnostic &PD,
                                           LangAS AS) {
PD.AddTaggedVal(static_cast<std::underlying_type_t<LangAS>>(AS),
                DiagnosticsEngine::ArgumentKind::ak_addrspace);
return PD;
7132}

7134/// Insertion operator for partial diagnostics. This allows sending Qualifiers
7135/// into a diagnostic with <<.
7136inline const StreamingDiagnostic &operator<<(const StreamingDiagnostic &PD,
                                           Qualifiers Q) {
PD.AddTaggedVal(Q.getAsOpaqueValue(),
                DiagnosticsEngine::ArgumentKind::ak_qual);
return PD;
7141}

7143/// Insertion operator for partial diagnostics.  This allows sending QualType's
7144/// into a diagnostic with <<.
7145inline const StreamingDiagnostic &operator<<(const StreamingDiagnostic &PD,
                                           QualType T) {
PD.AddTaggedVal(reinterpret_cast<intptr_t>(T.getAsOpaquePtr()),
                DiagnosticsEngine::ak_qualtype);
return PD;
7150}

7152// Helper class template that is used by Type::getAs to ensure that one does
7153// not try to look through a qualified type to get to an array type.
7154template <typename T>
7155using TypeIsArrayType =
  std::integral_constant<bool, std::is_same<T, ArrayType>::value ||
                                   std::is_base_of<ArrayType, T>::value>;

7159// Member-template getAs<specific type>'.
7160template <typename T> const T *Type::getAs() const {
static_assert(!TypeIsArrayType<T>::value,
              "ArrayType cannot be used with getAs!");

// If this is directly a T type, return it.
if (const auto *Ty = dyn_cast<T>(this))
  return Ty;

// If the canonical form of this type isn't the right kind, reject it.
if (!isa<T>(CanonicalType))
  return nullptr;

// If this is a typedef for the type, strip the typedef off without
// losing all typedef information.
return cast<T>(getUnqualifiedDesugaredType());
7175}

7177template <typename T> const T *Type::getAsAdjusted() const {
static_assert(!TypeIsArrayType<T>::value, "ArrayType cannot be used with getAsAdjusted!");

// If this is directly a T type, return it.
if (const auto *Ty = dyn_cast<T>(this))
  return Ty;

// If the canonical form of this type isn't the right kind, reject it.
if (!isa<T>(CanonicalType))
  return nullptr;

// Strip off type adjustments that do not modify the underlying nature of the
// type.
const Type *Ty = this;
while (Ty) {
  if (const auto *A = dyn_cast<AttributedType>(Ty))
    Ty = A->getModifiedType().getTypePtr();
  else if (const auto *E = dyn_cast<ElaboratedType>(Ty))
    Ty = E->desugar().getTypePtr();
  else if (const auto *P = dyn_cast<ParenType>(Ty))
    Ty = P->desugar().getTypePtr();
  else if (const auto *A = dyn_cast<AdjustedType>(Ty))
    Ty = A->desugar().getTypePtr();
  else if (const auto *M = dyn_cast<MacroQualifiedType>(Ty))
    Ty = M->desugar().getTypePtr();
  else
    break;
}

// Just because the canonical type is correct does not mean we can use cast<>,
// since we may not have stripped off all the sugar down to the base type.
return dyn_cast<T>(Ty);
7209}

7211inline const ArrayType *Type::getAsArrayTypeUnsafe() const {
// If this is directly an array type, return it.
if (const auto *arr = dyn_cast<ArrayType>(this))
  return arr;

// If the canonical form of this type isn't the right kind, reject it.
if (!isa<ArrayType>(CanonicalType))
  return nullptr;

// If this is a typedef for the type, strip the typedef off without
// losing all typedef information.
return cast<ArrayType>(getUnqualifiedDesugaredType());
7223}

7225template <typename T> const T *Type::castAs() const {
static_assert(!TypeIsArrayType<T>::value,
              "ArrayType cannot be used with castAs!");

if (const auto *ty = dyn_cast<T>(this)) return ty;
assert(isa<T>(CanonicalType))((void)0);
return cast<T>(getUnqualifiedDesugaredType());
7232}

7234inline const ArrayType *Type::castAsArrayTypeUnsafe() const {
assert(isa<ArrayType>(CanonicalType))((void)0);
if (const auto *arr = dyn_cast<ArrayType>(this)) return arr;
return cast<ArrayType>(getUnqualifiedDesugaredType());
7238}

7240DecayedType::DecayedType(QualType OriginalType, QualType DecayedPtr,
                       QualType CanonicalPtr)
  : AdjustedType(Decayed, OriginalType, DecayedPtr, CanonicalPtr) {
7243#ifndef NDEBUG1
QualType Adjusted = getAdjustedType();
(void)AttributedType::stripOuterNullability(Adjusted);
assert(isa<PointerType>(Adjusted))((void)0);
7247#endif
7248}

7250QualType DecayedType::getPointeeType() const {
QualType Decayed = getDecayedType();
(void)AttributedType::stripOuterNullability(Decayed);
return cast<PointerType>(Decayed)->getPointeeType();
7254}

7256// Get the decimal string representation of a fixed point type, represented
7257// as a scaled integer.
7258// TODO: At some point, we should change the arguments to instead just accept an
7259// APFixedPoint instead of APSInt and scale.
7260void FixedPointValueToString(SmallVectorImpl<char> &Str, llvm::APSInt Val,
                           unsigned Scale);

7263} // namespace clang

7265#endif // LLVM_CLANG_AST_TYPE_H