/usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/../../../llvm/lldb/source/Plugins/SymbolFile/NativePDB/PdbAstBuilder.cpp

Bug Summary

File:	src/gnu/usr.bin/clang/liblldbPluginSymbolFile/../../../llvm/lldb/source/Plugins/SymbolFile/NativePDB/PdbAstBuilder.cpp
Warning:	line 1205, column 29 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 PdbAstBuilder.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/liblldbPluginSymbolFile/obj -resource-dir /usr/local/lib/clang/13.0.0 -I /usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/../../../llvm/llvm/include -I /usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/../include -I /usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/obj -I /usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/obj/../include -D NDEBUG -D __STDC_LIMIT_MACROS -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D LLVM_PREFIX="/usr" -I /usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/../../../llvm/lldb/include -I /usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/../../../llvm/lldb/source -I /usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/../../../llvm/clang/include -I /usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/obj/../include/lldb/Plugins -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/liblldbPluginSymbolFile/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/liblldbPluginSymbolFile/../../../llvm/lldb/source/Plugins/SymbolFile/NativePDB/PdbAstBuilder.cpp

/usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/../../../llvm/lldb/source/Plugins/SymbolFile/NativePDB/PdbAstBuilder.cpp

→

1#include "PdbAstBuilder.h"

3#include "llvm/DebugInfo/CodeView/CVTypeVisitor.h"
4#include "llvm/DebugInfo/CodeView/LazyRandomTypeCollection.h"
5#include "llvm/DebugInfo/CodeView/RecordName.h"
6#include "llvm/DebugInfo/CodeView/SymbolDeserializer.h"
7#include "llvm/DebugInfo/CodeView/SymbolRecord.h"
8#include "llvm/DebugInfo/CodeView/SymbolRecordHelpers.h"
9#include "llvm/DebugInfo/CodeView/TypeDeserializer.h"
10#include "llvm/DebugInfo/CodeView/TypeVisitorCallbacks.h"
11#include "llvm/DebugInfo/PDB/Native/DbiStream.h"
12#include "llvm/DebugInfo/PDB/Native/PublicsStream.h"
13#include "llvm/DebugInfo/PDB/Native/SymbolStream.h"
14#include "llvm/DebugInfo/PDB/Native/TpiStream.h"
15#include "llvm/Demangle/MicrosoftDemangle.h"

17#include "Plugins/ExpressionParser/Clang/ClangASTMetadata.h"
18#include "Plugins/ExpressionParser/Clang/ClangUtil.h"
19#include "Plugins/Language/CPlusPlus/MSVCUndecoratedNameParser.h"
20#include "Plugins/TypeSystem/Clang/TypeSystemClang.h"
21#include "lldb/Core/Module.h"
22#include "lldb/Symbol/ObjectFile.h"
23#include "lldb/Utility/LLDBAssert.h"

25#include "PdbUtil.h"
26#include "UdtRecordCompleter.h"

28using namespace lldb_private;
29using namespace lldb_private::npdb;
30using namespace llvm::codeview;
31using namespace llvm::pdb;

33static llvm::Optional<PdbCompilandSymId> FindSymbolScope(PdbIndex &index,
                                                       PdbCompilandSymId id) {
CVSymbol sym = index.ReadSymbolRecord(id);
if (symbolOpensScope(sym.kind())) {
  // If this exact symbol opens a scope, we can just directly access its
  // parent.
  id.offset = getScopeParentOffset(sym);
  // Global symbols have parent offset of 0.  Return llvm::None to indicate
  // this.
  if (id.offset == 0)
    return llvm::None;
  return id;
}

// Otherwise we need to start at the beginning and iterate forward until we
// reach (or pass) this particular symbol
CompilandIndexItem &cii = index.compilands().GetOrCreateCompiland(id.modi);
const CVSymbolArray &syms = cii.m_debug_stream.getSymbolArray();

auto begin = syms.begin();
auto end = syms.at(id.offset);
std::vector<PdbCompilandSymId> scope_stack;

while (begin != end) {
  if (id.offset == begin.offset()) {
    // We have a match!  Return the top of the stack
    if (scope_stack.empty())
      return llvm::None;
    return scope_stack.back();
  }
  if (begin.offset() > id.offset) {
    // We passed it.  We couldn't even find this symbol record.
    lldbassert(false && "Invalid compiland symbol id!")lldb_private::lldb_assert(static_cast<bool>(false &&
 "Invalid compiland symbol id!"), "false && \"Invalid compiland symbol id!\""
, __FUNCTION__, "/usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/../../../llvm/lldb/source/Plugins/SymbolFile/NativePDB/PdbAstBuilder.cpp"
, 65);
    return llvm::None;
  }

  // We haven't found the symbol yet.  Check if we need to open or close the
  // scope stack.
  if (symbolOpensScope(begin->kind())) {
    // We can use the end offset of the scope to determine whether or not
    // we can just outright skip this entire scope.
    uint32_t scope_end = getScopeEndOffset(*begin);
    if (scope_end < id.modi) {
      begin = syms.at(scope_end);
    } else {
      // The symbol we're looking for is somewhere in this scope.
      scope_stack.emplace_back(id.modi, begin.offset());
    }
  } else if (symbolEndsScope(begin->kind())) {
    scope_stack.pop_back();
  }
  ++begin;
}

return llvm::None;
88}

90static clang::TagTypeKind TranslateUdtKind(const TagRecord &cr) {
switch (cr.Kind) {
case TypeRecordKind::Class:
  return clang::TTK_Class;
case TypeRecordKind::Struct:
  return clang::TTK_Struct;
case TypeRecordKind::Union:
  return clang::TTK_Union;
case TypeRecordKind::Interface:
  return clang::TTK_Interface;
case TypeRecordKind::Enum:
  return clang::TTK_Enum;
default:
  lldbassert(false && "Invalid tag record kind!")lldb_private::lldb_assert(static_cast<bool>(false &&
 "Invalid tag record kind!"), "false && \"Invalid tag record kind!\""
, __FUNCTION__, "/usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/../../../llvm/lldb/source/Plugins/SymbolFile/NativePDB/PdbAstBuilder.cpp"
, 103);
  return clang::TTK_Struct;
}
106}

108static bool IsCVarArgsFunction(llvm::ArrayRef<TypeIndex> args) {
if (args.empty())
  return false;
return args.back() == TypeIndex::None();
112}

114static bool
115AnyScopesHaveTemplateParams(llvm::ArrayRef<llvm::ms_demangle::Node *> scopes) {
for (llvm::ms_demangle::Node *n : scopes) {
  auto *idn = static_cast<llvm::ms_demangle::IdentifierNode *>(n);
  if (idn->TemplateParams)
    return true;
}
return false;
122}

124static llvm::Optional<clang::CallingConv>
125TranslateCallingConvention(llvm::codeview::CallingConvention conv) {
using CC = llvm::codeview::CallingConvention;
switch (conv) {

case CC::NearC:
case CC::FarC:
  return clang::CallingConv::CC_C;
case CC::NearPascal:
case CC::FarPascal:
  return clang::CallingConv::CC_X86Pascal;
case CC::NearFast:
case CC::FarFast:
  return clang::CallingConv::CC_X86FastCall;
case CC::NearStdCall:
case CC::FarStdCall:
  return clang::CallingConv::CC_X86StdCall;
case CC::ThisCall:
  return clang::CallingConv::CC_X86ThisCall;
case CC::NearVector:
  return clang::CallingConv::CC_X86VectorCall;
default:
  return llvm::None;
}
148}

150static llvm::Optional<CVTagRecord>
151GetNestedTagDefinition(const NestedTypeRecord &Record,
                     const CVTagRecord &parent, TpiStream &tpi) {
// An LF_NESTTYPE is essentially a nested typedef / using declaration, but it
// is also used to indicate the primary definition of a nested class.  That is
// to say, if you have:
// struct A {
//   struct B {};
//   using C = B;
// };
// Then in the debug info, this will appear as:
// LF_STRUCTURE `A::B` [type index = N]
// LF_STRUCTURE `A`
//   LF_NESTTYPE [name = `B`, index = N]
//   LF_NESTTYPE [name = `C`, index = N]
// In order to accurately reconstruct the decl context hierarchy, we need to
// know which ones are actual definitions and which ones are just aliases.

// If it's a simple type, then this is something like `using foo = int`.
if (Record.Type.isSimple())
  return llvm::None;

CVType cvt = tpi.getType(Record.Type);

if (!IsTagRecord(cvt))
  return llvm::None;

// If it's an inner definition, then treat whatever name we have here as a
// single component of a mangled name.  So we can inject it into the parent's
// mangled name to see if it matches.
CVTagRecord child = CVTagRecord::create(cvt);
std::string qname = std::string(parent.asTag().getUniqueName());
if (qname.size() < 4 || child.asTag().getUniqueName().size() < 4)
  return llvm::None;

// qname[3] is the tag type identifier (struct, class, union, etc).  Since the
// inner tag type is not necessarily the same as the outer tag type, re-write
// it to match the inner tag type.
qname[3] = child.asTag().getUniqueName()[3];
std::string piece;
if (qname[3] == 'W')
  piece = "4";
piece += Record.Name;
piece.push_back('@');
qname.insert(4, std::move(piece));
if (qname != child.asTag().UniqueName)
  return llvm::None;

return std::move(child);
199}

201static bool IsAnonymousNamespaceName(llvm::StringRef name) {
return name == "`anonymous namespace'" || name == "`anonymous-namespace'";
203}

205PdbAstBuilder::PdbAstBuilder(ObjectFile &obj, PdbIndex &index, TypeSystemClang &clang)
  : m_index(index), m_clang(clang) {
BuildParentMap();
208}

210lldb_private::CompilerDeclContext PdbAstBuilder::GetTranslationUnitDecl() {
return ToCompilerDeclContext(*m_clang.GetTranslationUnitDecl());
212}

214std::pair<clang::DeclContext *, std::string>
215PdbAstBuilder::CreateDeclInfoForType(const TagRecord &record, TypeIndex ti) {
// FIXME: Move this to GetDeclContextContainingUID.
if (!record.hasUniqueName())
  return CreateDeclInfoForUndecoratedName(record.Name);

llvm::ms_demangle::Demangler demangler;
StringView sv(record.UniqueName.begin(), record.UniqueName.size());
llvm::ms_demangle::TagTypeNode *ttn = demangler.parseTagUniqueName(sv);
if (demangler.Error)
  return {m_clang.GetTranslationUnitDecl(), std::string(record.UniqueName)};

llvm::ms_demangle::IdentifierNode *idn =
    ttn->QualifiedName->getUnqualifiedIdentifier();
std::string uname = idn->toString(llvm::ms_demangle::OF_NoTagSpecifier);

llvm::ms_demangle::NodeArrayNode *name_components =
    ttn->QualifiedName->Components;
llvm::ArrayRef<llvm::ms_demangle::Node *> scopes(name_components->Nodes,
                                                 name_components->Count - 1);

clang::DeclContext *context = m_clang.GetTranslationUnitDecl();

// If this type doesn't have a parent type in the debug info, then the best we
// can do is to say that it's either a series of namespaces (if the scope is
// non-empty), or the translation unit (if the scope is empty).
auto parent_iter = m_parent_types.find(ti);
if (parent_iter == m_parent_types.end()) {
  if (scopes.empty())
    return {context, uname};

  // If there is no parent in the debug info, but some of the scopes have
  // template params, then this is a case of bad debug info.  See, for
  // example, llvm.org/pr39607.  We don't want to create an ambiguity between
  // a NamespaceDecl and a CXXRecordDecl, so instead we create a class at
  // global scope with the fully qualified name.
  if (AnyScopesHaveTemplateParams(scopes))
    return {context, std::string(record.Name)};

  for (llvm::ms_demangle::Node *scope : scopes) {
    auto *nii = static_cast<llvm::ms_demangle::NamedIdentifierNode *>(scope);
    std::string str = nii->toString();
    context = GetOrCreateNamespaceDecl(str.c_str(), *context);
  }
  return {context, uname};
}

// Otherwise, all we need to do is get the parent type of this type and
// recurse into our lazy type creation / AST reconstruction logic to get an
// LLDB TypeSP for the parent.  This will cause the AST to automatically get
// the right DeclContext created for any parent.
clang::QualType parent_qt = GetOrCreateType(parent_iter->second);

context = clang::TagDecl::castToDeclContext(parent_qt->getAsTagDecl());
return {context, uname};
269}

271void PdbAstBuilder::BuildParentMap() {
LazyRandomTypeCollection &types = m_index.tpi().typeCollection();

llvm::DenseMap<TypeIndex, TypeIndex> forward_to_full;
llvm::DenseMap<TypeIndex, TypeIndex> full_to_forward;

struct RecordIndices {
  TypeIndex forward;
  TypeIndex full;
};

llvm::StringMap<RecordIndices> record_indices;

for (auto ti = types.getFirst(); ti; ti = types.getNext(*ti)) {
  CVType type = types.getType(*ti);
  if (!IsTagRecord(type))
    continue;

  CVTagRecord tag = CVTagRecord::create(type);

  RecordIndices &indices = record_indices[tag.asTag().getUniqueName()];
  if (tag.asTag().isForwardRef())
    indices.forward = *ti;
  else
    indices.full = *ti;

  if (indices.full != TypeIndex::None() &&
      indices.forward != TypeIndex::None()) {
    forward_to_full[indices.forward] = indices.full;
    full_to_forward[indices.full] = indices.forward;
  }

  // We're looking for LF_NESTTYPE records in the field list, so ignore
  // forward references (no field list), and anything without a nested class
  // (since there won't be any LF_NESTTYPE records).
  if (tag.asTag().isForwardRef() || !tag.asTag().containsNestedClass())
    continue;

  struct ProcessTpiStream : public TypeVisitorCallbacks {
    ProcessTpiStream(PdbIndex &index, TypeIndex parent,
                     const CVTagRecord &parent_cvt,
                     llvm::DenseMap<TypeIndex, TypeIndex> &parents)
        : index(index), parents(parents), parent(parent),
          parent_cvt(parent_cvt) {}

    PdbIndex &index;
    llvm::DenseMap<TypeIndex, TypeIndex> &parents;

    unsigned unnamed_type_index = 1;
    TypeIndex parent;
    const CVTagRecord &parent_cvt;

    llvm::Error visitKnownMember(CVMemberRecord &CVR,
                                 NestedTypeRecord &Record) override {
      std::string unnamed_type_name;
      if (Record.Name.empty()) {
        unnamed_type_name =
            llvm::formatv("<unnamed-type-$S{0}>", unnamed_type_index).str();
        Record.Name = unnamed_type_name;
        ++unnamed_type_index;
      }
      llvm::Optional<CVTagRecord> tag =
          GetNestedTagDefinition(Record, parent_cvt, index.tpi());
      if (!tag)
        return llvm::ErrorSuccess();

      parents[Record.Type] = parent;
      return llvm::ErrorSuccess();
    }
  };

  CVType field_list = m_index.tpi().getType(tag.asTag().FieldList);
  ProcessTpiStream process(m_index, *ti, tag, m_parent_types);
  llvm::Error error = visitMemberRecordStream(field_list.data(), process);
  if (error)
    llvm::consumeError(std::move(error));
}

// Now that we know the forward -> full mapping of all type indices, we can
// re-write all the indices.  At the end of this process, we want a mapping
// consisting of fwd -> full and full -> full for all child -> parent indices.
// We can re-write the values in place, but for the keys, we must save them
// off so that we don't modify the map in place while also iterating it.
std::vector<TypeIndex> full_keys;
std::vector<TypeIndex> fwd_keys;
for (auto &entry : m_parent_types) {
  TypeIndex key = entry.first;
  TypeIndex value = entry.second;

  auto iter = forward_to_full.find(value);
  if (iter != forward_to_full.end())
    entry.second = iter->second;

  iter = forward_to_full.find(key);
  if (iter != forward_to_full.end())
    fwd_keys.push_back(key);
  else
    full_keys.push_back(key);
}
for (TypeIndex fwd : fwd_keys) {
  TypeIndex full = forward_to_full[fwd];
  m_parent_types[full] = m_parent_types[fwd];
}
for (TypeIndex full : full_keys) {
  TypeIndex fwd = full_to_forward[full];
  m_parent_types[fwd] = m_parent_types[full];
}

// Now that
380}

382static bool isLocalVariableType(SymbolKind K) {
switch (K) {
case S_REGISTER:
case S_REGREL32:
case S_LOCAL:
  return true;
default:
  break;
}
return false;
392}

394static std::string
395RenderScopeList(llvm::ArrayRef<llvm::ms_demangle::Node *> nodes) {
lldbassert(!nodes.empty())lldb_private::lldb_assert(static_cast<bool>(!nodes.empty
()), "!nodes.empty()", __FUNCTION__, "/usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/../../../llvm/lldb/source/Plugins/SymbolFile/NativePDB/PdbAstBuilder.cpp"
, 396);

std::string result = nodes.front()->toString();
nodes = nodes.drop_front();
while (!nodes.empty()) {
  result += "::";
  result += nodes.front()->toString(llvm::ms_demangle::OF_NoTagSpecifier);
  nodes = nodes.drop_front();
}
return result;
406}

408static llvm::Optional<PublicSym32> FindPublicSym(const SegmentOffset &addr,
                                               SymbolStream &syms,
                                               PublicsStream &publics) {
llvm::FixedStreamArray<ulittle32_t> addr_map = publics.getAddressMap();
auto iter = std::lower_bound(
    addr_map.begin(), addr_map.end(), addr,
    [&](const ulittle32_t &x, const SegmentOffset &y) {
      CVSymbol s1 = syms.readRecord(x);
      lldbassert(s1.kind() == S_PUB32)lldb_private::lldb_assert(static_cast<bool>(s1.kind() ==
 S_PUB32), "s1.kind() == S_PUB32", __FUNCTION__, "/usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/../../../llvm/lldb/source/Plugins/SymbolFile/NativePDB/PdbAstBuilder.cpp"
, 416);
      PublicSym32 p1;
      llvm::cantFail(SymbolDeserializer::deserializeAs<PublicSym32>(s1, p1));
      if (p1.Segment < y.segment)
        return true;
      return p1.Offset < y.offset;
    });
if (iter == addr_map.end())
  return llvm::None;
CVSymbol sym = syms.readRecord(*iter);
lldbassert(sym.kind() == S_PUB32)lldb_private::lldb_assert(static_cast<bool>(sym.kind() ==
 S_PUB32), "sym.kind() == S_PUB32", __FUNCTION__, "/usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/../../../llvm/lldb/source/Plugins/SymbolFile/NativePDB/PdbAstBuilder.cpp"
, 426);
PublicSym32 p;
llvm::cantFail(SymbolDeserializer::deserializeAs<PublicSym32>(sym, p));
if (p.Segment == addr.segment && p.Offset == addr.offset)
  return p;
return llvm::None;
432}

434clang::Decl *PdbAstBuilder::GetOrCreateSymbolForId(PdbCompilandSymId id) {
CVSymbol cvs = m_index.ReadSymbolRecord(id);

if (isLocalVariableType(cvs.kind())) {
  clang::DeclContext *scope = GetParentDeclContext(id);
  clang::Decl *scope_decl = clang::Decl::castFromDeclContext(scope);
  PdbCompilandSymId scope_id(id.modi, m_decl_to_status[scope_decl].uid);
  return GetOrCreateVariableDecl(scope_id, id);
}

switch (cvs.kind()) {
case S_GPROC32:
case S_LPROC32:
  return GetOrCreateFunctionDecl(id);
case S_GDATA32:
case S_LDATA32:
case S_GTHREAD32:
case S_CONSTANT:
  // global variable
  return nullptr;
case S_BLOCK32:
  return GetOrCreateBlockDecl(id);
default:
  return nullptr;
}
459}

461llvm::Optional<CompilerDecl> PdbAstBuilder::GetOrCreateDeclForUid(PdbSymUid uid) {
if (clang::Decl *result = TryGetDecl(uid))
  return ToCompilerDecl(*result);

clang::Decl *result = nullptr;
switch (uid.kind()) {
case PdbSymUidKind::CompilandSym:
  result = GetOrCreateSymbolForId(uid.asCompilandSym());
  break;
case PdbSymUidKind::Type: {
  clang::QualType qt = GetOrCreateType(uid.asTypeSym());
  if (auto *tag = qt->getAsTagDecl()) {
    result = tag;
    break;
  }
  return llvm::None;
}
default:
  return llvm::None;
}
m_uid_to_decl[toOpaqueUid(uid)] = result;
return ToCompilerDecl(*result);
483}

485clang::DeclContext *PdbAstBuilder::GetOrCreateDeclContextForUid(PdbSymUid uid) {
if (uid.kind() == PdbSymUidKind::CompilandSym) {
  if (uid.asCompilandSym().offset == 0)
    return FromCompilerDeclContext(GetTranslationUnitDecl());
}
auto option = GetOrCreateDeclForUid(uid);
if (!option)
  return nullptr;
clang::Decl *decl = FromCompilerDecl(option.getValue());
if (!decl)
  return nullptr;

return clang::Decl::castToDeclContext(decl);
498}

500std::pair<clang::DeclContext *, std::string>
501PdbAstBuilder::CreateDeclInfoForUndecoratedName(llvm::StringRef name) {
MSVCUndecoratedNameParser parser(name);
llvm::ArrayRef<MSVCUndecoratedNameSpecifier> specs = parser.GetSpecifiers();

auto context = FromCompilerDeclContext(GetTranslationUnitDecl());

llvm::StringRef uname = specs.back().GetBaseName();
specs = specs.drop_back();
if (specs.empty())
  return {context, std::string(name)};

llvm::StringRef scope_name = specs.back().GetFullName();

// It might be a class name, try that first.
std::vector<TypeIndex> types = m_index.tpi().findRecordsByName(scope_name);
while (!types.empty()) {
  clang::QualType qt = GetOrCreateType(types.back());
  clang::TagDecl *tag = qt->getAsTagDecl();
  if (tag)
    return {clang::TagDecl::castToDeclContext(tag), std::string(uname)};
  types.pop_back();
}

// If that fails, treat it as a series of namespaces.
for (const MSVCUndecoratedNameSpecifier &spec : specs) {
  std::string ns_name = spec.GetBaseName().str();
  context = GetOrCreateNamespaceDecl(ns_name.c_str(), *context);
}
return {context, std::string(uname)};
530}

532clang::DeclContext *
533PdbAstBuilder::GetParentDeclContextForSymbol(const CVSymbol &sym) {
if (!SymbolHasAddress(sym))
  return CreateDeclInfoForUndecoratedName(getSymbolName(sym)).first;
SegmentOffset addr = GetSegmentAndOffset(sym);
llvm::Optional<PublicSym32> pub =
    FindPublicSym(addr, m_index.symrecords(), m_index.publics());
if (!pub)
  return CreateDeclInfoForUndecoratedName(getSymbolName(sym)).first;

llvm::ms_demangle::Demangler demangler;
StringView name{pub->Name.begin(), pub->Name.size()};
llvm::ms_demangle::SymbolNode *node = demangler.parse(name);
if (!node)
  return FromCompilerDeclContext(GetTranslationUnitDecl());
llvm::ArrayRef<llvm::ms_demangle::Node *> name_components{
    node->Name->Components->Nodes, node->Name->Components->Count - 1};

if (!name_components.empty()) {
  // Render the current list of scope nodes as a fully qualified name, and
  // look it up in the debug info as a type name.  If we find something,
  // this is a type (which may itself be prefixed by a namespace).  If we
  // don't, this is a list of namespaces.
  std::string qname = RenderScopeList(name_components);
  std::vector<TypeIndex> matches = m_index.tpi().findRecordsByName(qname);
  while (!matches.empty()) {
    clang::QualType qt = GetOrCreateType(matches.back());
    clang::TagDecl *tag = qt->getAsTagDecl();
    if (tag)
      return clang::TagDecl::castToDeclContext(tag);
    matches.pop_back();
  }
}

// It's not a type.  It must be a series of namespaces.
auto context = FromCompilerDeclContext(GetTranslationUnitDecl());
while (!name_components.empty()) {
  std::string ns = name_components.front()->toString();
  context = GetOrCreateNamespaceDecl(ns.c_str(), *context);
  name_components = name_components.drop_front();
}
return context;
574}

576clang::DeclContext *PdbAstBuilder::GetParentDeclContext(PdbSymUid uid) {
// We must do this *without* calling GetOrCreate on the current uid, as
// that would be an infinite recursion.
switch (uid.kind()) {
case PdbSymUidKind::CompilandSym: {
  llvm::Optional<PdbCompilandSymId> scope =
      FindSymbolScope(m_index, uid.asCompilandSym());
  if (scope)
    return GetOrCreateDeclContextForUid(*scope);

  CVSymbol sym = m_index.ReadSymbolRecord(uid.asCompilandSym());
  return GetParentDeclContextForSymbol(sym);
}
case PdbSymUidKind::Type: {
  // It could be a namespace, class, or global.  We don't support nested
  // functions yet.  Anyway, we just need to consult the parent type map.
  PdbTypeSymId type_id = uid.asTypeSym();
  auto iter = m_parent_types.find(type_id.index);
  if (iter == m_parent_types.end())
    return FromCompilerDeclContext(GetTranslationUnitDecl());
  return GetOrCreateDeclContextForUid(PdbTypeSymId(iter->second));
}
case PdbSymUidKind::FieldListMember:
  // In this case the parent DeclContext is the one for the class that this
  // member is inside of.
  break;
case PdbSymUidKind::GlobalSym: {
  // If this refers to a compiland symbol, just recurse in with that symbol.
  // The only other possibilities are S_CONSTANT and S_UDT, in which case we
  // need to parse the undecorated name to figure out the scope, then look
  // that up in the TPI stream.  If it's found, it's a type, othewrise it's
  // a series of namespaces.
  // FIXME: do this.
  CVSymbol global = m_index.ReadSymbolRecord(uid.asGlobalSym());
  switch (global.kind()) {
  case SymbolKind::S_GDATA32:
  case SymbolKind::S_LDATA32:
    return GetParentDeclContextForSymbol(global);
  case SymbolKind::S_PROCREF:
  case SymbolKind::S_LPROCREF: {
    ProcRefSym ref{global.kind()};
    llvm::cantFail(
        SymbolDeserializer::deserializeAs<ProcRefSym>(global, ref));
    PdbCompilandSymId cu_sym_id{ref.modi(), ref.SymOffset};
    return GetParentDeclContext(cu_sym_id);
  }
  case SymbolKind::S_CONSTANT:
  case SymbolKind::S_UDT:
    return CreateDeclInfoForUndecoratedName(getSymbolName(global)).first;
  default:
    break;
  }
  break;
}
default:
  break;
}
return FromCompilerDeclContext(GetTranslationUnitDecl());
634}

636bool PdbAstBuilder::CompleteType(clang::QualType qt) {
clang::TagDecl *tag = qt->getAsTagDecl();
if (!tag)
  return false;

return CompleteTagDecl(*tag);
642}

644bool PdbAstBuilder::CompleteTagDecl(clang::TagDecl &tag) {
// If this is not in our map, it's an error.
auto status_iter = m_decl_to_status.find(&tag);
lldbassert(status_iter != m_decl_to_status.end())lldb_private::lldb_assert(static_cast<bool>(status_iter
 != m_decl_to_status.end()), "status_iter != m_decl_to_status.end()"
, __FUNCTION__, "/usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/../../../llvm/lldb/source/Plugins/SymbolFile/NativePDB/PdbAstBuilder.cpp"
, 647);

// If it's already complete, just return.
DeclStatus &status = status_iter->second;
if (status.resolved)
  return true;

PdbTypeSymId type_id = PdbSymUid(status.uid).asTypeSym();

lldbassert(IsTagRecord(type_id, m_index.tpi()))lldb_private::lldb_assert(static_cast<bool>(IsTagRecord
(type_id, m_index.tpi())), "IsTagRecord(type_id, m_index.tpi())"
, __FUNCTION__, "/usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/../../../llvm/lldb/source/Plugins/SymbolFile/NativePDB/PdbAstBuilder.cpp"
, 656);

clang::QualType tag_qt = m_clang.getASTContext().getTypeDeclType(&tag);
TypeSystemClang::SetHasExternalStorage(tag_qt.getAsOpaquePtr(), false);

TypeIndex tag_ti = type_id.index;
CVType cvt = m_index.tpi().getType(tag_ti);
if (cvt.kind() == LF_MODIFIER)
  tag_ti = LookThroughModifierRecord(cvt);

PdbTypeSymId best_ti = GetBestPossibleDecl(tag_ti, m_index.tpi());
cvt = m_index.tpi().getType(best_ti.index);
lldbassert(IsTagRecord(cvt))lldb_private::lldb_assert(static_cast<bool>(IsTagRecord
(cvt)), "IsTagRecord(cvt)", __FUNCTION__, "/usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/../../../llvm/lldb/source/Plugins/SymbolFile/NativePDB/PdbAstBuilder.cpp"
, 668);

if (IsForwardRefUdt(cvt)) {
  // If we can't find a full decl for this forward ref anywhere in the debug
  // info, then we have no way to complete it.
  return false;
}

TypeIndex field_list_ti = GetFieldListIndex(cvt);
CVType field_list_cvt = m_index.tpi().getType(field_list_ti);
if (field_list_cvt.kind() != LF_FIELDLIST)
  return false;

// Visit all members of this class, then perform any finalization necessary
// to complete the class.
CompilerType ct = ToCompilerType(tag_qt);
UdtRecordCompleter completer(best_ti, ct, tag, *this, m_index);
auto error =
    llvm::codeview::visitMemberRecordStream(field_list_cvt.data(), completer);
completer.complete();

status.resolved = true;
if (!error)
  return true;

llvm::consumeError(std::move(error));
return false;
695}

697clang::QualType PdbAstBuilder::CreateSimpleType(TypeIndex ti) {
if (ti == TypeIndex::NullptrT())
  return GetBasicType(lldb::eBasicTypeNullPtr);

if (ti.getSimpleMode() != SimpleTypeMode::Direct) {
  clang::QualType direct_type = GetOrCreateType(ti.makeDirect());
  return m_clang.getASTContext().getPointerType(direct_type);
}

if (ti.getSimpleKind() == SimpleTypeKind::NotTranslated)
  return {};

lldb::BasicType bt = GetCompilerTypeForSimpleKind(ti.getSimpleKind());
if (bt == lldb::eBasicTypeInvalid)
  return {};

return GetBasicType(bt);
714}

716clang::QualType PdbAstBuilder::CreatePointerType(const PointerRecord &pointer) {
clang::QualType pointee_type = GetOrCreateType(pointer.ReferentType);

// This can happen for pointers to LF_VTSHAPE records, which we shouldn't
// create in the AST.
if (pointee_type.isNull())
  return {};

if (pointer.isPointerToMember()) {
  MemberPointerInfo mpi = pointer.getMemberInfo();
  clang::QualType class_type = GetOrCreateType(mpi.ContainingType);

  return m_clang.getASTContext().getMemberPointerType(
      pointee_type, class_type.getTypePtr());
}

clang::QualType pointer_type;
if (pointer.getMode() == PointerMode::LValueReference)
  pointer_type = m_clang.getASTContext().getLValueReferenceType(pointee_type);
else if (pointer.getMode() == PointerMode::RValueReference)
  pointer_type = m_clang.getASTContext().getRValueReferenceType(pointee_type);
else
  pointer_type = m_clang.getASTContext().getPointerType(pointee_type);

if ((pointer.getOptions() & PointerOptions::Const) != PointerOptions::None)
  pointer_type.addConst();

if ((pointer.getOptions() & PointerOptions::Volatile) != PointerOptions::None)
  pointer_type.addVolatile();

if ((pointer.getOptions() & PointerOptions::Restrict) != PointerOptions::None)
  pointer_type.addRestrict();

return pointer_type;
750}

752clang::QualType
753PdbAstBuilder::CreateModifierType(const ModifierRecord &modifier) {
clang::QualType unmodified_type = GetOrCreateType(modifier.ModifiedType);
if (unmodified_type.isNull())
  return {};

if ((modifier.Modifiers & ModifierOptions::Const) != ModifierOptions::None)
  unmodified_type.addConst();
if ((modifier.Modifiers & ModifierOptions::Volatile) != ModifierOptions::None)
  unmodified_type.addVolatile();

return unmodified_type;
764}

766clang::QualType PdbAstBuilder::CreateRecordType(PdbTypeSymId id,
                                              const TagRecord &record) {
clang::DeclContext *context = nullptr;
std::string uname;
std::tie(context, uname) = CreateDeclInfoForType(record, id.index);
clang::TagTypeKind ttk = TranslateUdtKind(record);
lldb::AccessType access =
    (ttk == clang::TTK_Class) ? lldb::eAccessPrivate : lldb::eAccessPublic;

ClangASTMetadata metadata;
metadata.SetUserID(toOpaqueUid(id));
metadata.SetIsDynamicCXXType(false);

CompilerType ct =
    m_clang.CreateRecordType(context, OptionalClangModuleID(), access, uname,
                             ttk, lldb::eLanguageTypeC_plus_plus, &metadata);

lldbassert(ct.IsValid())lldb_private::lldb_assert(static_cast<bool>(ct.IsValid(
)), "ct.IsValid()", __FUNCTION__, "/usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/../../../llvm/lldb/source/Plugins/SymbolFile/NativePDB/PdbAstBuilder.cpp"
, 783);

TypeSystemClang::StartTagDeclarationDefinition(ct);

// Even if it's possible, don't complete it at this point. Just mark it
// forward resolved, and if/when LLDB needs the full definition, it can
// ask us.
clang::QualType result =
    clang::QualType::getFromOpaquePtr(ct.GetOpaqueQualType());

TypeSystemClang::SetHasExternalStorage(result.getAsOpaquePtr(), true);
return result;
795}

797clang::Decl *PdbAstBuilder::TryGetDecl(PdbSymUid uid) const {
auto iter = m_uid_to_decl.find(toOpaqueUid(uid));
if (iter != m_uid_to_decl.end())
  return iter->second;
return nullptr;
802}

804clang::NamespaceDecl *
805PdbAstBuilder::GetOrCreateNamespaceDecl(const char *name,
                                      clang::DeclContext &context) {
return m_clang.GetUniqueNamespaceDeclaration(
    IsAnonymousNamespaceName(name) ? nullptr : name, &context,
    OptionalClangModuleID());
810}

812clang::BlockDecl *
813PdbAstBuilder::GetOrCreateBlockDecl(PdbCompilandSymId block_id) {
if (clang::Decl *decl = TryGetDecl(block_id))
  return llvm::dyn_cast<clang::BlockDecl>(decl);

clang::DeclContext *scope = GetParentDeclContext(block_id);

clang::BlockDecl *block_decl =
    m_clang.CreateBlockDeclaration(scope, OptionalClangModuleID());
m_uid_to_decl.insert({toOpaqueUid(block_id), block_decl});

DeclStatus status;
status.resolved = true;
status.uid = toOpaqueUid(block_id);
m_decl_to_status.insert({block_decl, status});

return block_decl;
829}

831clang::VarDecl *PdbAstBuilder::CreateVariableDecl(PdbSymUid uid, CVSymbol sym,
                                                clang::DeclContext &scope) {
VariableInfo var_info = GetVariableNameInfo(sym);
clang::QualType qt = GetOrCreateType(var_info.type);

clang::VarDecl *var_decl = m_clang.CreateVariableDeclaration(
    &scope, OptionalClangModuleID(), var_info.name.str().c_str(), qt);

m_uid_to_decl[toOpaqueUid(uid)] = var_decl;
DeclStatus status;
status.resolved = true;
status.uid = toOpaqueUid(uid);
m_decl_to_status.insert({var_decl, status});
return var_decl;
845}

847clang::VarDecl *
848PdbAstBuilder::GetOrCreateVariableDecl(PdbCompilandSymId scope_id,
                                     PdbCompilandSymId var_id) {
if (clang::Decl *decl = TryGetDecl(var_id))
  return llvm::dyn_cast<clang::VarDecl>(decl);

clang::DeclContext *scope = GetOrCreateDeclContextForUid(scope_id);

CVSymbol sym = m_index.ReadSymbolRecord(var_id);
return CreateVariableDecl(PdbSymUid(var_id), sym, *scope);
857}

859clang::VarDecl *PdbAstBuilder::GetOrCreateVariableDecl(PdbGlobalSymId var_id) {
if (clang::Decl *decl = TryGetDecl(var_id))
  return llvm::dyn_cast<clang::VarDecl>(decl);

CVSymbol sym = m_index.ReadSymbolRecord(var_id);
auto context = FromCompilerDeclContext(GetTranslationUnitDecl());
return CreateVariableDecl(PdbSymUid(var_id), sym, *context);
866}

868clang::TypedefNameDecl *
869PdbAstBuilder::GetOrCreateTypedefDecl(PdbGlobalSymId id) {
if (clang::Decl *decl = TryGetDecl(id))
  return llvm::dyn_cast<clang::TypedefNameDecl>(decl);

CVSymbol sym = m_index.ReadSymbolRecord(id);
lldbassert(sym.kind() == S_UDT)lldb_private::lldb_assert(static_cast<bool>(sym.kind() ==
 S_UDT), "sym.kind() == S_UDT", __FUNCTION__, "/usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/../../../llvm/lldb/source/Plugins/SymbolFile/NativePDB/PdbAstBuilder.cpp"
, 874);
UDTSym udt = llvm::cantFail(SymbolDeserializer::deserializeAs<UDTSym>(sym));

clang::DeclContext *scope = GetParentDeclContext(id);

PdbTypeSymId real_type_id{udt.Type, false};
clang::QualType qt = GetOrCreateType(real_type_id);

std::string uname = std::string(DropNameScope(udt.Name));

CompilerType ct = ToCompilerType(qt).CreateTypedef(
    uname.c_str(), ToCompilerDeclContext(*scope), 0);
clang::TypedefNameDecl *tnd = m_clang.GetAsTypedefDecl(ct);
DeclStatus status;
status.resolved = true;
status.uid = toOpaqueUid(id);
m_decl_to_status.insert({tnd, status});
return tnd;
892}

894clang::QualType PdbAstBuilder::GetBasicType(lldb::BasicType type) {
CompilerType ct = m_clang.GetBasicType(type);
return clang::QualType::getFromOpaquePtr(ct.GetOpaqueQualType());
897}

899clang::QualType PdbAstBuilder::CreateType(PdbTypeSymId type) {
if (type.index.isSimple())
  return CreateSimpleType(type.index);

CVType cvt = m_index.tpi().getType(type.index);

if (cvt.kind() == LF_MODIFIER) {
  ModifierRecord modifier;
  llvm::cantFail(
      TypeDeserializer::deserializeAs<ModifierRecord>(cvt, modifier));
  return CreateModifierType(modifier);
}

if (cvt.kind() == LF_POINTER) {
  PointerRecord pointer;
  llvm::cantFail(
      TypeDeserializer::deserializeAs<PointerRecord>(cvt, pointer));
  return CreatePointerType(pointer);
}

if (IsTagRecord(cvt)) {
  CVTagRecord tag = CVTagRecord::create(cvt);
  if (tag.kind() == CVTagRecord::Union)
    return CreateRecordType(type.index, tag.asUnion());
  if (tag.kind() == CVTagRecord::Enum)
    return CreateEnumType(type.index, tag.asEnum());
  return CreateRecordType(type.index, tag.asClass());
}

if (cvt.kind() == LF_ARRAY) {
  ArrayRecord ar;
  llvm::cantFail(TypeDeserializer::deserializeAs<ArrayRecord>(cvt, ar));
  return CreateArrayType(ar);
}

if (cvt.kind() == LF_PROCEDURE) {
  ProcedureRecord pr;
  llvm::cantFail(TypeDeserializer::deserializeAs<ProcedureRecord>(cvt, pr));
  return CreateFunctionType(pr.ArgumentList, pr.ReturnType, pr.CallConv);
}

if (cvt.kind() == LF_MFUNCTION) {
  MemberFunctionRecord mfr;
  llvm::cantFail(
      TypeDeserializer::deserializeAs<MemberFunctionRecord>(cvt, mfr));
  return CreateFunctionType(mfr.ArgumentList, mfr.ReturnType, mfr.CallConv);
}

return {};
948}

950clang::QualType PdbAstBuilder::GetOrCreateType(PdbTypeSymId type) {
lldb::user_id_t uid = toOpaqueUid(type);
auto iter = m_uid_to_type.find(uid);
if (iter != m_uid_to_type.end())
  return iter->second;

PdbTypeSymId best_type = GetBestPossibleDecl(type, m_index.tpi());

clang::QualType qt;
if (best_type.index != type.index) {
  // This is a forward decl.  Call GetOrCreate on the full decl, then map the
  // forward decl id to the full decl QualType.
  clang::QualType qt = GetOrCreateType(best_type);
  m_uid_to_type[toOpaqueUid(type)] = qt;
  return qt;
}

// This is either a full decl, or a forward decl with no matching full decl
// in the debug info.
qt = CreateType(type);
m_uid_to_type[toOpaqueUid(type)] = qt;
if (IsTagRecord(type, m_index.tpi())) {
  clang::TagDecl *tag = qt->getAsTagDecl();
  lldbassert(m_decl_to_status.count(tag) == 0)lldb_private::lldb_assert(static_cast<bool>(m_decl_to_status
.count(tag) == 0), "m_decl_to_status.count(tag) == 0", __FUNCTION__
, "/usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/../../../llvm/lldb/source/Plugins/SymbolFile/NativePDB/PdbAstBuilder.cpp"
, 973);

  DeclStatus &status = m_decl_to_status[tag];
  status.uid = uid;
  status.resolved = false;
}
return qt;
980}

982clang::FunctionDecl *
983PdbAstBuilder::GetOrCreateFunctionDecl(PdbCompilandSymId func_id) {
if (clang::Decl *decl = TryGetDecl(func_id))
  return llvm::dyn_cast<clang::FunctionDecl>(decl);

clang::DeclContext *parent = GetParentDeclContext(PdbSymUid(func_id));
std::string context_name;
if (clang::NamespaceDecl *ns = llvm::dyn_cast<clang::NamespaceDecl>(parent)) {
  context_name = ns->getQualifiedNameAsString();
} else if (clang::TagDecl *tag = llvm::dyn_cast<clang::TagDecl>(parent)) {
  context_name = tag->getQualifiedNameAsString();
}

CVSymbol cvs = m_index.ReadSymbolRecord(func_id);
ProcSym proc(static_cast<SymbolRecordKind>(cvs.kind()));
llvm::cantFail(SymbolDeserializer::deserializeAs<ProcSym>(cvs, proc));

PdbTypeSymId type_id(proc.FunctionType);
clang::QualType qt = GetOrCreateType(type_id);
if (qt.isNull())
  return nullptr;

clang::StorageClass storage = clang::SC_None;
if (proc.Kind == SymbolRecordKind::ProcSym)
  storage = clang::SC_Static;

const clang::FunctionProtoType *func_type =
    llvm::dyn_cast<clang::FunctionProtoType>(qt);

CompilerType func_ct = ToCompilerType(qt);

llvm::StringRef proc_name = proc.Name;
proc_name.consume_front(context_name);
proc_name.consume_front("::");

clang::FunctionDecl *function_decl = m_clang.CreateFunctionDeclaration(
    parent, OptionalClangModuleID(), proc_name, func_ct, storage, false);

lldbassert(m_uid_to_decl.count(toOpaqueUid(func_id)) == 0)lldb_private::lldb_assert(static_cast<bool>(m_uid_to_decl
.count(toOpaqueUid(func_id)) == 0), "m_uid_to_decl.count(toOpaqueUid(func_id)) == 0"
, __FUNCTION__, "/usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/../../../llvm/lldb/source/Plugins/SymbolFile/NativePDB/PdbAstBuilder.cpp"
, 1020);
m_uid_to_decl[toOpaqueUid(func_id)] = function_decl;
DeclStatus status;
status.resolved = true;
status.uid = toOpaqueUid(func_id);
m_decl_to_status.insert({function_decl, status});

CreateFunctionParameters(func_id, *function_decl, func_type->getNumParams());

return function_decl;
1030}

1032void PdbAstBuilder::CreateFunctionParameters(PdbCompilandSymId func_id,
                                           clang::FunctionDecl &function_decl,
                                           uint32_t param_count) {
CompilandIndexItem *cii = m_index.compilands().GetCompiland(func_id.modi);
CVSymbolArray scope =
    cii->m_debug_stream.getSymbolArrayForScope(func_id.offset);

auto begin = scope.begin();
auto end = scope.end();
std::vector<clang::ParmVarDecl *> params;
while (begin != end && param_count > 0) {
  uint32_t record_offset = begin.offset();
  CVSymbol sym = *begin++;

  TypeIndex param_type;
  llvm::StringRef param_name;
  switch (sym.kind()) {
  case S_REGREL32: {
    RegRelativeSym reg(SymbolRecordKind::RegRelativeSym);
    cantFail(SymbolDeserializer::deserializeAs<RegRelativeSym>(sym, reg));
    param_type = reg.Type;
    param_name = reg.Name;
    break;
  }
  case S_REGISTER: {
    RegisterSym reg(SymbolRecordKind::RegisterSym);
    cantFail(SymbolDeserializer::deserializeAs<RegisterSym>(sym, reg));
    param_type = reg.Index;
    param_name = reg.Name;
    break;
  }
  case S_LOCAL: {
    LocalSym local(SymbolRecordKind::LocalSym);
    cantFail(SymbolDeserializer::deserializeAs<LocalSym>(sym, local));
    if ((local.Flags & LocalSymFlags::IsParameter) == LocalSymFlags::None)
      continue;
    param_type = local.Type;
    param_name = local.Name;
    break;
  }
  case S_BLOCK32:
    // All parameters should come before the first block.  If that isn't the
    // case, then perhaps this is bad debug info that doesn't contain
    // information about all parameters.
    return;
  default:
    continue;
  }

  PdbCompilandSymId param_uid(func_id.modi, record_offset);
  clang::QualType qt = GetOrCreateType(param_type);

  CompilerType param_type_ct = m_clang.GetType(qt);
  clang::ParmVarDecl *param = m_clang.CreateParameterDeclaration(
      &function_decl, OptionalClangModuleID(), param_name.str().c_str(),
      param_type_ct, clang::SC_None, true);
  lldbassert(m_uid_to_decl.count(toOpaqueUid(param_uid)) == 0)lldb_private::lldb_assert(static_cast<bool>(m_uid_to_decl
.count(toOpaqueUid(param_uid)) == 0), "m_uid_to_decl.count(toOpaqueUid(param_uid)) == 0"
, __FUNCTION__, "/usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/../../../llvm/lldb/source/Plugins/SymbolFile/NativePDB/PdbAstBuilder.cpp"
, 1088);

  m_uid_to_decl[toOpaqueUid(param_uid)] = param;
  params.push_back(param);
  --param_count;
}

if (!params.empty())
  m_clang.SetFunctionParameters(&function_decl, params);
1097}

1099clang::QualType PdbAstBuilder::CreateEnumType(PdbTypeSymId id,
                                            const EnumRecord &er) {
clang::DeclContext *decl_context = nullptr;
std::string uname;
std::tie(decl_context, uname) = CreateDeclInfoForType(er, id.index);
clang::QualType underlying_type = GetOrCreateType(er.UnderlyingType);

Declaration declaration;
CompilerType enum_ct = m_clang.CreateEnumerationType(
    uname.c_str(), decl_context, OptionalClangModuleID(), declaration,
    ToCompilerType(underlying_type), er.isScoped());

TypeSystemClang::StartTagDeclarationDefinition(enum_ct);
TypeSystemClang::SetHasExternalStorage(enum_ct.GetOpaqueQualType(), true);

return clang::QualType::getFromOpaquePtr(enum_ct.GetOpaqueQualType());
1115}

1117clang::QualType PdbAstBuilder::CreateArrayType(const ArrayRecord &ar) {
clang::QualType element_type = GetOrCreateType(ar.ElementType);

uint64_t element_count =
    ar.Size / GetSizeOfType({ar.ElementType}, m_index.tpi());

CompilerType array_ct = m_clang.CreateArrayType(ToCompilerType(element_type),
                                                element_count, false);
return clang::QualType::getFromOpaquePtr(array_ct.GetOpaqueQualType());
1126}

1128clang::QualType PdbAstBuilder::CreateFunctionType(
  TypeIndex args_type_idx, TypeIndex return_type_idx,
  llvm::codeview::CallingConvention calling_convention) {
TpiStream &stream = m_index.tpi();
CVType args_cvt = stream.getType(args_type_idx);
ArgListRecord args;
llvm::cantFail(
    TypeDeserializer::deserializeAs<ArgListRecord>(args_cvt, args));

llvm::ArrayRef<TypeIndex> arg_indices = llvm::makeArrayRef(args.ArgIndices);
bool is_variadic = IsCVarArgsFunction(arg_indices);
if (is_variadic)
  arg_indices = arg_indices.drop_back();

std::vector<CompilerType> arg_types;
arg_types.reserve(arg_indices.size());

for (TypeIndex arg_index : arg_indices) {
  clang::QualType arg_type = GetOrCreateType(arg_index);
  arg_types.push_back(ToCompilerType(arg_type));
}

clang::QualType return_type = GetOrCreateType(return_type_idx);

llvm::Optional<clang::CallingConv> cc =
    TranslateCallingConvention(calling_convention);
if (!cc)
  return {};

CompilerType return_ct = ToCompilerType(return_type);
CompilerType func_sig_ast_type = m_clang.CreateFunctionType(
    return_ct, arg_types.data(), arg_types.size(), is_variadic, 0, *cc);

return clang::QualType::getFromOpaquePtr(
    func_sig_ast_type.GetOpaqueQualType());
1163}

1165static bool isTagDecl(clang::DeclContext &context) {
return !!llvm::dyn_cast<clang::TagDecl>(&context);
1167}

1169static bool isFunctionDecl(clang::DeclContext &context) {
return !!llvm::dyn_cast<clang::FunctionDecl>(&context);
1171}

1173static bool isBlockDecl(clang::DeclContext &context) {
return !!llvm::dyn_cast<clang::BlockDecl>(&context);
1175}

1177void PdbAstBuilder::ParseAllNamespacesPlusChildrenOf(
  llvm::Optional<llvm::StringRef> parent) {
TypeIndex ti{m_index.tpi().TypeIndexBegin()};
for (const CVType &cvt : m_index.tpi().typeArray()) {
  PdbTypeSymId tid{ti};
  ++ti;

  if (!IsTagRecord(cvt))
5
←
Assuming the condition is false→
6
←
Taking false branch→
    continue;

  CVTagRecord tag = CVTagRecord::create(cvt);

  if (!parent.hasValue()) {
7
←
Calling 'Optional::hasValue'→
12
←
Returning from 'Optional::hasValue'→
13
←
Taking false branch→
    clang::QualType qt = GetOrCreateType(tid);
    CompleteType(qt);
    continue;
  }

  // Call CreateDeclInfoForType unconditionally so that the namespace info
  // gets created.  But only call CreateRecordType if the namespace name
  // matches.
  clang::DeclContext *context = nullptr;
  std::string uname;
  std::tie(context, uname) = CreateDeclInfoForType(tag.asTag(), tid.index);
  if (!context->isNamespace())
14
←
Calling 'DeclContext::isNamespace'→
17
←
Returning from 'DeclContext::isNamespace'→
18
←
Taking false branch→
    continue;

  clang::NamespaceDecl *ns = llvm::dyn_cast<clang::NamespaceDecl>(context);
19
←
Assuming 'context' is not a 'NamespaceDecl'→
20
←
'ns' initialized to a null pointer value→
  std::string actual_ns = ns->getQualifiedNameAsString();
21
←
Called C++ object pointer is null
  if (llvm::StringRef(actual_ns).startswith(*parent)) {
    clang::QualType qt = GetOrCreateType(tid);
    CompleteType(qt);
    continue;
  }
}

uint32_t module_count = m_index.dbi().modules().getModuleCount();
for (uint16_t modi = 0; modi < module_count; ++modi) {
  CompilandIndexItem &cii = m_index.compilands().GetOrCreateCompiland(modi);
  const CVSymbolArray &symbols = cii.m_debug_stream.getSymbolArray();
  auto iter = symbols.begin();
  while (iter != symbols.end()) {
    PdbCompilandSymId sym_id{modi, iter.offset()};

    switch (iter->kind()) {
    case S_GPROC32:
    case S_LPROC32:
      GetOrCreateFunctionDecl(sym_id);
      iter = symbols.at(getScopeEndOffset(*iter));
      break;
    case S_GDATA32:
    case S_GTHREAD32:
    case S_LDATA32:
    case S_LTHREAD32:
      GetOrCreateVariableDecl(PdbCompilandSymId(modi, 0), sym_id);
      ++iter;
      break;
    default:
      ++iter;
      continue;
    }
  }
}
1240}

1242static CVSymbolArray skipFunctionParameters(clang::Decl &decl,
                                          const CVSymbolArray &symbols) {
clang::FunctionDecl *func_decl = llvm::dyn_cast<clang::FunctionDecl>(&decl);
if (!func_decl)
  return symbols;
unsigned int params = func_decl->getNumParams();
if (params == 0)
  return symbols;

CVSymbolArray result = symbols;

while (!result.empty()) {
  if (params == 0)
    return result;

  CVSymbol sym = *result.begin();
  result.drop_front();

  if (!isLocalVariableType(sym.kind()))
    continue;

  --params;
}
return result;
1266}

1268void PdbAstBuilder::ParseBlockChildren(PdbCompilandSymId block_id) {
CVSymbol sym = m_index.ReadSymbolRecord(block_id);
lldbassert(sym.kind() == S_GPROC32 || sym.kind() == S_LPROC32 ||lldb_private::lldb_assert(static_cast<bool>(sym.kind() ==
 S_GPROC32 || sym.kind() == S_LPROC32 || sym.kind() == S_BLOCK32
), "sym.kind() == S_GPROC32 || sym.kind() == S_LPROC32 || sym.kind() == S_BLOCK32"
, __FUNCTION__, "/usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/../../../llvm/lldb/source/Plugins/SymbolFile/NativePDB/PdbAstBuilder.cpp"
, 1271)
           sym.kind() == S_BLOCK32)lldb_private::lldb_assert(static_cast<bool>(sym.kind() ==
 S_GPROC32 || sym.kind() == S_LPROC32 || sym.kind() == S_BLOCK32
), "sym.kind() == S_GPROC32 || sym.kind() == S_LPROC32 || sym.kind() == S_BLOCK32"
, __FUNCTION__, "/usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/../../../llvm/lldb/source/Plugins/SymbolFile/NativePDB/PdbAstBuilder.cpp"
, 1271);
CompilandIndexItem &cii =
    m_index.compilands().GetOrCreateCompiland(block_id.modi);
CVSymbolArray symbols =
    cii.m_debug_stream.getSymbolArrayForScope(block_id.offset);

// Function parameters should already have been created when the function was
// parsed.
if (sym.kind() == S_GPROC32 || sym.kind() == S_LPROC32)
  symbols =
      skipFunctionParameters(*m_uid_to_decl[toOpaqueUid(block_id)], symbols);

auto begin = symbols.begin();
while (begin != symbols.end()) {
  PdbCompilandSymId child_sym_id(block_id.modi, begin.offset());
  GetOrCreateSymbolForId(child_sym_id);
  if (begin->kind() == S_BLOCK32) {
    ParseBlockChildren(child_sym_id);
    begin = symbols.at(getScopeEndOffset(*begin));
  }
  ++begin;
}
1293}

1295void PdbAstBuilder::ParseDeclsForSimpleContext(clang::DeclContext &context) {

clang::Decl *decl = clang::Decl::castFromDeclContext(&context);
lldbassert(decl)lldb_private::lldb_assert(static_cast<bool>(decl), "decl"
, __FUNCTION__, "/usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/../../../llvm/lldb/source/Plugins/SymbolFile/NativePDB/PdbAstBuilder.cpp"
, 1298);

auto iter = m_decl_to_status.find(decl);
lldbassert(iter != m_decl_to_status.end())lldb_private::lldb_assert(static_cast<bool>(iter != m_decl_to_status
.end()), "iter != m_decl_to_status.end()", __FUNCTION__, "/usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/../../../llvm/lldb/source/Plugins/SymbolFile/NativePDB/PdbAstBuilder.cpp"
, 1301);

if (auto *tag = llvm::dyn_cast<clang::TagDecl>(&context)) {
  CompleteTagDecl(*tag);
  return;
}

if (isFunctionDecl(context) || isBlockDecl(context)) {
  PdbCompilandSymId block_id = PdbSymUid(iter->second.uid).asCompilandSym();
  ParseBlockChildren(block_id);
}
1312}

1314void PdbAstBuilder::ParseDeclsForContext(clang::DeclContext &context) {
// Namespaces aren't explicitly represented in the debug info, and the only
// way to parse them is to parse all type info, demangling every single type
// and trying to reconstruct the DeclContext hierarchy this way.  Since this
// is an expensive operation, we have to special case it so that we do other
// work (such as parsing the items that appear within the namespaces) at the
// same time.
if (context.isTranslationUnit()) {
1
Taking false branch→
  ParseAllNamespacesPlusChildrenOf(llvm::None);
  return;
}

if (context.isNamespace()) {
2
←
Taking true branch→
  clang::NamespaceDecl &ns = *llvm::dyn_cast<clang::NamespaceDecl>(&context);
3
←
Assuming the object is a 'NamespaceDecl'→
  std::string qname = ns.getQualifiedNameAsString();
  ParseAllNamespacesPlusChildrenOf(llvm::StringRef{qname});
4
←
Calling 'PdbAstBuilder::ParseAllNamespacesPlusChildrenOf'→
  return;
}

if (isTagDecl(context) || isFunctionDecl(context) || isBlockDecl(context)) {
  ParseDeclsForSimpleContext(context);
  return;
}
1337}

1339CompilerDecl PdbAstBuilder::ToCompilerDecl(clang::Decl &decl) {
return m_clang.GetCompilerDecl(&decl);
1341}

1343CompilerType PdbAstBuilder::ToCompilerType(clang::QualType qt) {
return {&m_clang, qt.getAsOpaquePtr()};
1345}

1347CompilerDeclContext
1348PdbAstBuilder::ToCompilerDeclContext(clang::DeclContext &context) {
return m_clang.CreateDeclContext(&context);
1350}

1352clang::Decl * PdbAstBuilder::FromCompilerDecl(CompilerDecl decl) {
return ClangUtil::GetDecl(decl);
1354}

1356clang::DeclContext *
1357PdbAstBuilder::FromCompilerDeclContext(CompilerDeclContext context) {
return static_cast<clang::DeclContext *>(context.GetOpaqueDeclContext());
1359}

1361void PdbAstBuilder::Dump(Stream &stream) { m_clang.Dump(stream); }

←

/usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/../../../llvm/llvm/include/llvm/ADT/Optional.h

→

1//===- Optional.h - Simple variant for passing optional values --*- 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//  This file provides Optional, a template class modeled in the spirit of
10//  OCaml's 'opt' variant.  The idea is to strongly type whether or not
11//  a value can be optional.
12//
13//===----------------------------------------------------------------------===//
14 
15#ifndef LLVM_ADT_OPTIONAL_H
16#define LLVM_ADT_OPTIONAL_H
17 
18#include "llvm/ADT/Hashing.h"
19#include "llvm/ADT/None.h"
20#include "llvm/ADT/STLForwardCompat.h"
21#include "llvm/Support/Compiler.h"
22#include "llvm/Support/type_traits.h"
23#include <cassert>
24#include <memory>
25#include <new>
26#include <utility>
27 
28namespace llvm {
29 
30class raw_ostream;
31 
32namespace optional_detail {
33 
34/// Storage for any type.
35//
36// The specialization condition intentionally uses
37// llvm::is_trivially_copy_constructible instead of
38// std::is_trivially_copy_constructible.  GCC versions prior to 7.4 may
39// instantiate the copy constructor of `T` when
40// std::is_trivially_copy_constructible is instantiated.  This causes
41// compilation to fail if we query the trivially copy constructible property of
42// a class which is not copy constructible.
43//
44// The current implementation of OptionalStorage insists that in order to use
45// the trivial specialization, the value_type must be trivially copy
46// constructible and trivially copy assignable due to =default implementations
47// of the copy/move constructor/assignment.  It does not follow that this is
48// necessarily the case std::is_trivially_copyable is true (hence the expanded
49// specialization condition).
50//
51// The move constructible / assignable conditions emulate the remaining behavior
52// of std::is_trivially_copyable.
53template <typename T, bool = (llvm::is_trivially_copy_constructible<T>::value &&
54                              std::is_trivially_copy_assignable<T>::value &&
55                              (std::is_trivially_move_constructible<T>::value ||
56                               !std::is_move_constructible<T>::value) &&
57                              (std::is_trivially_move_assignable<T>::value ||
58                               !std::is_move_assignable<T>::value))>
59class OptionalStorage {
60  union {
61    char empty;
62    T value;
63  };
64  bool hasVal;
65 
66public:
67  ~OptionalStorage() { reset(); }
68 
69  constexpr OptionalStorage() noexcept : empty(), hasVal(false) {}
70 
71  constexpr OptionalStorage(OptionalStorage const &other) : OptionalStorage() {
72    if (other.hasValue()) {
73      emplace(other.value);
74    }
75  }
76  constexpr OptionalStorage(OptionalStorage &&other) : OptionalStorage() {
77    if (other.hasValue()) {
78      emplace(std::move(other.value));
79    }
80  }
81 
82  template <class... Args>
83  constexpr explicit OptionalStorage(in_place_t, Args &&... args)
84      : value(std::forward<Args>(args)...), hasVal(true) {}
85 
86  void reset() noexcept {
87    if (hasVal) {
88      value.~T();
89      hasVal = false;
90    }
91  }
92 
93  constexpr bool hasValue() const noexcept { return hasVal; }
94 
95  T &getValue() LLVM_LVALUE_FUNCTION& noexcept {
96    assert(hasVal)((void)0);
97    return value;
98  }
99  constexpr T const &getValue() const LLVM_LVALUE_FUNCTION& noexcept {
100    assert(hasVal)((void)0);
101    return value;
102  }
103#if LLVM_HAS_RVALUE_REFERENCE_THIS1
104  T &&getValue() && noexcept {
105    assert(hasVal)((void)0);
106    return std::move(value);
107  }
108#endif
109 
110  template <class... Args> void emplace(Args &&... args) {
111    reset();
112    ::new ((void *)std::addressof(value)) T(std::forward<Args>(args)...);
113    hasVal = true;
114  }
115 
116  OptionalStorage &operator=(T const &y) {
117    if (hasValue()) {
118      value = y;
119    } else {
120      ::new ((void *)std::addressof(value)) T(y);
121      hasVal = true;
122    }
123    return *this;
124  }
125  OptionalStorage &operator=(T &&y) {
126    if (hasValue()) {
127      value = std::move(y);
128    } else {
129      ::new ((void *)std::addressof(value)) T(std::move(y));
130      hasVal = true;
131    }
132    return *this;
133  }
134 
135  OptionalStorage &operator=(OptionalStorage const &other) {
136    if (other.hasValue()) {
137      if (hasValue()) {
138        value = other.value;
139      } else {
140        ::new ((void *)std::addressof(value)) T(other.value);
141        hasVal = true;
142      }
143    } else {
144      reset();
145    }
146    return *this;
147  }
148 
149  OptionalStorage &operator=(OptionalStorage &&other) {
150    if (other.hasValue()) {
151      if (hasValue()) {
152        value = std::move(other.value);
153      } else {
154        ::new ((void *)std::addressof(value)) T(std::move(other.value));
155        hasVal = true;
156      }
157    } else {
158      reset();
159    }
160    return *this;
161  }
162};
163 
164template <typename T> class OptionalStorage<T, true> {
165  union {
166    char empty;
167    T value;
168  };
169  bool hasVal = false;
170 
171public:
172  ~OptionalStorage() = default;
173 
174  constexpr OptionalStorage() noexcept : empty{} {}
175 
176  constexpr OptionalStorage(OptionalStorage const &other) = default;
177  constexpr OptionalStorage(OptionalStorage &&other) = default;
178 
179  OptionalStorage &operator=(OptionalStorage const &other) = default;
180  OptionalStorage &operator=(OptionalStorage &&other) = default;
181 
182  template <class... Args>
183  constexpr explicit OptionalStorage(in_place_t, Args &&... args)
184      : value(std::forward<Args>(args)...), hasVal(true) {}
185 
186  void reset() noexcept {
187    if (hasVal) {
188      value.~T();
189      hasVal = false;
190    }
191  }
192 
193  constexpr bool hasValue() const noexcept { return hasVal; }
9
←
Returning the value 1, which participates in a condition later→
194 
195  T &getValue() LLVM_LVALUE_FUNCTION& noexcept {
196    assert(hasVal)((void)0);
197    return value;
198  }
199  constexpr T const &getValue() const LLVM_LVALUE_FUNCTION& noexcept {
200    assert(hasVal)((void)0);
201    return value;
202  }
203#if LLVM_HAS_RVALUE_REFERENCE_THIS1
204  T &&getValue() && noexcept {
205    assert(hasVal)((void)0);
206    return std::move(value);
207  }
208#endif
209 
210  template <class... Args> void emplace(Args &&... args) {
211    reset();
212    ::new ((void *)std::addressof(value)) T(std::forward<Args>(args)...);
213    hasVal = true;
214  }
215 
216  OptionalStorage &operator=(T const &y) {
217    if (hasValue()) {
218      value = y;
219    } else {
220      ::new ((void *)std::addressof(value)) T(y);
221      hasVal = true;
222    }
223    return *this;
224  }
225  OptionalStorage &operator=(T &&y) {
226    if (hasValue()) {
227      value = std::move(y);
228    } else {
229      ::new ((void *)std::addressof(value)) T(std::move(y));
230      hasVal = true;
231    }
232    return *this;
233  }
234};
235 
236} // namespace optional_detail
237 
238template <typename T> class Optional {
239  optional_detail::OptionalStorage<T> Storage;
240 
241public:
242  using value_type = T;
243 
244  constexpr Optional() {}
245  constexpr Optional(NoneType) {}
246 
247  constexpr Optional(const T &y) : Storage(in_place, y) {}
248  constexpr Optional(const Optional &O) = default;
249 
250  constexpr Optional(T &&y) : Storage(in_place, std::move(y)) {}
251  constexpr Optional(Optional &&O) = default;
252 
253  template <typename... ArgTypes>
254  constexpr Optional(in_place_t, ArgTypes &&...Args)
255      : Storage(in_place, std::forward<ArgTypes>(Args)...) {}
256 
257  Optional &operator=(T &&y) {
258    Storage = std::move(y);
259    return *this;
260  }
261  Optional &operator=(Optional &&O) = default;
262 
263  /// Create a new object by constructing it in place with the given arguments.
264  template <typename... ArgTypes> void emplace(ArgTypes &&... Args) {
265    Storage.emplace(std::forward<ArgTypes>(Args)...);
266  }
267 
268  static constexpr Optional create(const T *y) {
269    return y ? Optional(*y) : Optional();
270  }
271 
272  Optional &operator=(const T &y) {
273    Storage = y;
274    return *this;
275  }
276  Optional &operator=(const Optional &O) = default;
277 
278  void reset() { Storage.reset(); }
279 
280  constexpr const T *getPointer() const { return &Storage.getValue(); }
281  T *getPointer() { return &Storage.getValue(); }
282  constexpr const T &getValue() const LLVM_LVALUE_FUNCTION& {
283    return Storage.getValue();
284  }
285  T &getValue() LLVM_LVALUE_FUNCTION& { return Storage.getValue(); }
286 
287  constexpr explicit operator bool() const { return hasValue(); }
288  constexpr bool hasValue() const { return Storage.hasValue(); }
8
←
Calling 'OptionalStorage::hasValue'→
10
←
Returning from 'OptionalStorage::hasValue'→
11
←
Returning the value 1, which participates in a condition later→
289  constexpr const T *operator->() const { return getPointer(); }
290  T *operator->() { return getPointer(); }
291  constexpr const T &operator*() const LLVM_LVALUE_FUNCTION& {
292    return getValue();
293  }
294  T &operator*() LLVM_LVALUE_FUNCTION& { return getValue(); }
295 
296  template <typename U>
297  constexpr T getValueOr(U &&value) const LLVM_LVALUE_FUNCTION& {
298    return hasValue() ? getValue() : std::forward<U>(value);
299  }
300 
301  /// Apply a function to the value if present; otherwise return None.
302  template <class Function>
303  auto map(const Function &F) const LLVM_LVALUE_FUNCTION&
304      -> Optional<decltype(F(getValue()))> {
305    if (*this) return F(getValue());
306    return None;
307  }
308 
309#if LLVM_HAS_RVALUE_REFERENCE_THIS1
310  T &&getValue() && { return std::move(Storage.getValue()); }
311  T &&operator*() && { return std::move(Storage.getValue()); }
312 
313  template <typename U>
314  T getValueOr(U &&value) && {
315    return hasValue() ? std::move(getValue()) : std::forward<U>(value);
316  }
317 
318  /// Apply a function to the value if present; otherwise return None.
319  template <class Function>
320  auto map(const Function &F) &&
321      -> Optional<decltype(F(std::move(*this).getValue()))> {
322    if (*this) return F(std::move(*this).getValue());
323    return None;
324  }
325#endif
326};
327 
328template <class T> llvm::hash_code hash_value(const Optional<T> &O) {
329  return O ? hash_combine(true, *O) : hash_value(false);
330}
331 
332template <typename T, typename U>
333constexpr bool operator==(const Optional<T> &X, const Optional<U> &Y) {
334  if (X && Y)
335    return *X == *Y;
336  return X.hasValue() == Y.hasValue();
337}
338 
339template <typename T, typename U>
340constexpr bool operator!=(const Optional<T> &X, const Optional<U> &Y) {
341  return !(X == Y);
342}
343 
344template <typename T, typename U>
345constexpr bool operator<(const Optional<T> &X, const Optional<U> &Y) {
346  if (X && Y)
347    return *X < *Y;
348  return X.hasValue() < Y.hasValue();
349}
350 
351template <typename T, typename U>
352constexpr bool operator<=(const Optional<T> &X, const Optional<U> &Y) {
353  return !(Y < X);
354}
355 
356template <typename T, typename U>
357constexpr bool operator>(const Optional<T> &X, const Optional<U> &Y) {
358  return Y < X;
359}
360 
361template <typename T, typename U>
362constexpr bool operator>=(const Optional<T> &X, const Optional<U> &Y) {
363  return !(X < Y);
364}
365 
366template <typename T>
367constexpr bool operator==(const Optional<T> &X, NoneType) {
368  return !X;
369}
370 
371template <typename T>
372constexpr bool operator==(NoneType, const Optional<T> &X) {
373  return X == None;
374}
375 
376template <typename T>
377constexpr bool operator!=(const Optional<T> &X, NoneType) {
378  return !(X == None);
379}
380 
381template <typename T>
382constexpr bool operator!=(NoneType, const Optional<T> &X) {
383  return X != None;
384}
385 
386template <typename T> constexpr bool operator<(const Optional<T> &, NoneType) {
387  return false;
388}
389 
390template <typename T> constexpr bool operator<(NoneType, const Optional<T> &X) {
391  return X.hasValue();
392}
393 
394template <typename T>
395constexpr bool operator<=(const Optional<T> &X, NoneType) {
396  return !(None < X);
397}
398 
399template <typename T>
400constexpr bool operator<=(NoneType, const Optional<T> &X) {
401  return !(X < None);
402}
403 
404template <typename T> constexpr bool operator>(const Optional<T> &X, NoneType) {
405  return None < X;
406}
407 
408template <typename T> constexpr bool operator>(NoneType, const Optional<T> &X) {
409  return X < None;
410}
411 
412template <typename T>
413constexpr bool operator>=(const Optional<T> &X, NoneType) {
414  return None <= X;
415}
416 
417template <typename T>
418constexpr bool operator>=(NoneType, const Optional<T> &X) {
419  return X <= None;
420}
421 
422template <typename T>
423constexpr bool operator==(const Optional<T> &X, const T &Y) {
424  return X && *X == Y;
425}
426 
427template <typename T>
428constexpr bool operator==(const T &X, const Optional<T> &Y) {
429  return Y && X == *Y;
430}
431 
432template <typename T>
433constexpr bool operator!=(const Optional<T> &X, const T &Y) {
434  return !(X == Y);
435}
436 
437template <typename T>
438constexpr bool operator!=(const T &X, const Optional<T> &Y) {
439  return !(X == Y);
440}
441 
442template <typename T>
443constexpr bool operator<(const Optional<T> &X, const T &Y) {
444  return !X || *X < Y;
445}
446 
447template <typename T>
448constexpr bool operator<(const T &X, const Optional<T> &Y) {
449  return Y && X < *Y;
450}
451 
452template <typename T>
453constexpr bool operator<=(const Optional<T> &X, const T &Y) {
454  return !(Y < X);
455}
456 
457template <typename T>
458constexpr bool operator<=(const T &X, const Optional<T> &Y) {
459  return !(Y < X);
460}
461 
462template <typename T>
463constexpr bool operator>(const Optional<T> &X, const T &Y) {
464  return Y < X;
465}
466 
467template <typename T>
468constexpr bool operator>(const T &X, const Optional<T> &Y) {
469  return Y < X;
470}
471 
472template <typename T>
473constexpr bool operator>=(const Optional<T> &X, const T &Y) {
474  return !(X < Y);
475}
476 
477template <typename T>
478constexpr bool operator>=(const T &X, const Optional<T> &Y) {
479  return !(X < Y);
480}
481 
482raw_ostream &operator<<(raw_ostream &OS, NoneType);
483 
484template <typename T, typename = decltype(std::declval<raw_ostream &>()
485                                          << std::declval<const T &>())>
486raw_ostream &operator<<(raw_ostream &OS, const Optional<T> &O) {
487  if (O)
488    OS << *O;
489  else
490    OS << None;
491  return OS;
492}
493 
494} // end namespace llvm
495 
496#endif // LLVM_ADT_OPTIONAL_H

←

/usr/src/gnu/usr.bin/clang/liblldbPluginSymbolFile/../../../llvm/clang/include/clang/AST/DeclBase.h

1//===- DeclBase.h - Base Classes for representing declarations --*- 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//  This file defines the Decl and DeclContext interfaces.
10//
11//===----------------------------------------------------------------------===//

13#ifndef LLVM_CLANG_AST_DECLBASE_H
14#define LLVM_CLANG_AST_DECLBASE_H

16#include "clang/AST/ASTDumperUtils.h"
17#include "clang/AST/AttrIterator.h"
18#include "clang/AST/DeclarationName.h"
19#include "clang/Basic/IdentifierTable.h"
20#include "clang/Basic/LLVM.h"
21#include "clang/Basic/SourceLocation.h"
22#include "clang/Basic/Specifiers.h"
23#include "llvm/ADT/ArrayRef.h"
24#include "llvm/ADT/PointerIntPair.h"
25#include "llvm/ADT/PointerUnion.h"
26#include "llvm/ADT/iterator.h"
27#include "llvm/ADT/iterator_range.h"
28#include "llvm/Support/Casting.h"
29#include "llvm/Support/Compiler.h"
30#include "llvm/Support/PrettyStackTrace.h"
31#include "llvm/Support/VersionTuple.h"
32#include <algorithm>
33#include <cassert>
34#include <cstddef>
35#include <iterator>
36#include <string>
37#include <type_traits>
38#include <utility>

40namespace clang {

42class ASTContext;
43class ASTMutationListener;
44class Attr;
45class BlockDecl;
46class DeclContext;
47class ExternalSourceSymbolAttr;
48class FunctionDecl;
49class FunctionType;
50class IdentifierInfo;
51enum Linkage : unsigned char;
52class LinkageSpecDecl;
53class Module;
54class NamedDecl;
55class ObjCCategoryDecl;
56class ObjCCategoryImplDecl;
57class ObjCContainerDecl;
58class ObjCImplDecl;
59class ObjCImplementationDecl;
60class ObjCInterfaceDecl;
61class ObjCMethodDecl;
62class ObjCProtocolDecl;
63struct PrintingPolicy;
64class RecordDecl;
65class SourceManager;
66class Stmt;
67class StoredDeclsMap;
68class TemplateDecl;
69class TemplateParameterList;
70class TranslationUnitDecl;
71class UsingDirectiveDecl;

73/// Captures the result of checking the availability of a
74/// declaration.
75enum AvailabilityResult {
AR_Available = 0,
AR_NotYetIntroduced,
AR_Deprecated,
AR_Unavailable
80};

82/// Decl - This represents one declaration (or definition), e.g. a variable,
83/// typedef, function, struct, etc.
84///
85/// Note: There are objects tacked on before the *beginning* of Decl
86/// (and its subclasses) in its Decl::operator new(). Proper alignment
87/// of all subclasses (not requiring more than the alignment of Decl) is
88/// asserted in DeclBase.cpp.
89class alignas(8) Decl {
90public:
/// Lists the kind of concrete classes of Decl.
enum Kind {
93#define DECL(DERIVED, BASE) DERIVED,
94#define ABSTRACT_DECL(DECL)
95#define DECL_RANGE(BASE, START, END) \
      first##BASE = START, last##BASE = END,
97#define LAST_DECL_RANGE(BASE, START, END) \
      first##BASE = START, last##BASE = END
99#include "clang/AST/DeclNodes.inc"
};

/// A placeholder type used to construct an empty shell of a
/// decl-derived type that will be filled in later (e.g., by some
/// deserialization method).
struct EmptyShell {};

/// IdentifierNamespace - The different namespaces in which
/// declarations may appear.  According to C99 6.2.3, there are
/// four namespaces, labels, tags, members and ordinary
/// identifiers.  C++ describes lookup completely differently:
/// certain lookups merely "ignore" certain kinds of declarations,
/// usually based on whether the declaration is of a type, etc.
///
/// These are meant as bitmasks, so that searches in
/// C++ can look into the "tag" namespace during ordinary lookup.
///
/// Decl currently provides 15 bits of IDNS bits.
enum IdentifierNamespace {
  /// Labels, declared with 'x:' and referenced with 'goto x'.
  IDNS_Label               = 0x0001,

  /// Tags, declared with 'struct foo;' and referenced with
  /// 'struct foo'.  All tags are also types.  This is what
  /// elaborated-type-specifiers look for in C.
  /// This also contains names that conflict with tags in the
  /// same scope but that are otherwise ordinary names (non-type
  /// template parameters and indirect field declarations).
  IDNS_Tag                 = 0x0002,

  /// Types, declared with 'struct foo', typedefs, etc.
  /// This is what elaborated-type-specifiers look for in C++,
  /// but note that it's ill-formed to find a non-tag.
  IDNS_Type                = 0x0004,

  /// Members, declared with object declarations within tag
  /// definitions.  In C, these can only be found by "qualified"
  /// lookup in member expressions.  In C++, they're found by
  /// normal lookup.
  IDNS_Member              = 0x0008,

  /// Namespaces, declared with 'namespace foo {}'.
  /// Lookup for nested-name-specifiers find these.
  IDNS_Namespace           = 0x0010,

  /// Ordinary names.  In C, everything that's not a label, tag,
  /// member, or function-local extern ends up here.
  IDNS_Ordinary            = 0x0020,

  /// Objective C \@protocol.
  IDNS_ObjCProtocol        = 0x0040,

  /// This declaration is a friend function.  A friend function
  /// declaration is always in this namespace but may also be in
  /// IDNS_Ordinary if it was previously declared.
  IDNS_OrdinaryFriend      = 0x0080,

  /// This declaration is a friend class.  A friend class
  /// declaration is always in this namespace but may also be in
  /// IDNS_Tag|IDNS_Type if it was previously declared.
  IDNS_TagFriend           = 0x0100,

  /// This declaration is a using declaration.  A using declaration
  /// *introduces* a number of other declarations into the current
  /// scope, and those declarations use the IDNS of their targets,
  /// but the actual using declarations go in this namespace.
  IDNS_Using               = 0x0200,

  /// This declaration is a C++ operator declared in a non-class
  /// context.  All such operators are also in IDNS_Ordinary.
  /// C++ lexical operator lookup looks for these.
  IDNS_NonMemberOperator   = 0x0400,

  /// This declaration is a function-local extern declaration of a
  /// variable or function. This may also be IDNS_Ordinary if it
  /// has been declared outside any function. These act mostly like
  /// invisible friend declarations, but are also visible to unqualified
  /// lookup within the scope of the declaring function.
  IDNS_LocalExtern         = 0x0800,

  /// This declaration is an OpenMP user defined reduction construction.
  IDNS_OMPReduction        = 0x1000,

  /// This declaration is an OpenMP user defined mapper.
  IDNS_OMPMapper           = 0x2000,
};

/// ObjCDeclQualifier - 'Qualifiers' written next to the return and
/// parameter types in method declarations.  Other than remembering
/// them and mangling them into the method's signature string, these
/// are ignored by the compiler; they are consumed by certain
/// remote-messaging frameworks.
///
/// in, inout, and out are mutually exclusive and apply only to
/// method parameters.  bycopy and byref are mutually exclusive and
/// apply only to method parameters (?).  oneway applies only to
/// results.  All of these expect their corresponding parameter to
/// have a particular type.  None of this is currently enforced by
/// clang.
///
/// This should be kept in sync with ObjCDeclSpec::ObjCDeclQualifier.
enum ObjCDeclQualifier {
  OBJC_TQ_None = 0x0,
  OBJC_TQ_In = 0x1,
  OBJC_TQ_Inout = 0x2,
  OBJC_TQ_Out = 0x4,
  OBJC_TQ_Bycopy = 0x8,
  OBJC_TQ_Byref = 0x10,
  OBJC_TQ_Oneway = 0x20,

  /// The nullability qualifier is set when the nullability of the
  /// result or parameter was expressed via a context-sensitive
  /// keyword.
  OBJC_TQ_CSNullability = 0x40
};

/// The kind of ownership a declaration has, for visibility purposes.
/// This enumeration is designed such that higher values represent higher
/// levels of name hiding.
enum class ModuleOwnershipKind : unsigned {
  /// This declaration is not owned by a module.
  Unowned,

  /// This declaration has an owning module, but is globally visible
  /// (typically because its owning module is visible and we know that
  /// modules cannot later become hidden in this compilation).
  /// After serialization and deserialization, this will be converted
  /// to VisibleWhenImported.
  Visible,

  /// This declaration has an owning module, and is visible when that
  /// module is imported.
  VisibleWhenImported,

  /// This declaration has an owning module, but is only visible to
  /// lookups that occur within that module.
  ModulePrivate
};

239protected:
/// The next declaration within the same lexical
/// DeclContext. These pointers form the linked list that is
/// traversed via DeclContext's decls_begin()/decls_end().
///
/// The extra two bits are used for the ModuleOwnershipKind.
llvm::PointerIntPair<Decl *, 2, ModuleOwnershipKind> NextInContextAndBits;

247private:
friend class DeclContext;

struct MultipleDC {
  DeclContext *SemanticDC;
  DeclContext *LexicalDC;
};

/// DeclCtx - Holds either a DeclContext* or a MultipleDC*.
/// For declarations that don't contain C++ scope specifiers, it contains
/// the DeclContext where the Decl was declared.
/// For declarations with C++ scope specifiers, it contains a MultipleDC*
/// with the context where it semantically belongs (SemanticDC) and the
/// context where it was lexically declared (LexicalDC).
/// e.g.:
///
///   namespace A {
///      void f(); // SemanticDC == LexicalDC == 'namespace A'
///   }
///   void A::f(); // SemanticDC == namespace 'A'
///                // LexicalDC == global namespace
llvm::PointerUnion<DeclContext*, MultipleDC*> DeclCtx;

bool isInSemaDC() const { return DeclCtx.is<DeclContext*>(); }
bool isOutOfSemaDC() const { return DeclCtx.is<MultipleDC*>(); }

MultipleDC *getMultipleDC() const {
  return DeclCtx.get<MultipleDC*>();
}

DeclContext *getSemanticDC() const {
  return DeclCtx.get<DeclContext*>();
}

/// Loc - The location of this decl.
SourceLocation Loc;

/// DeclKind - This indicates which class this is.
unsigned DeclKind : 7;

/// InvalidDecl - This indicates a semantic error occurred.
unsigned InvalidDecl :  1;

/// HasAttrs - This indicates whether the decl has attributes or not.
unsigned HasAttrs : 1;

/// Implicit - Whether this declaration was implicitly generated by
/// the implementation rather than explicitly written by the user.
unsigned Implicit : 1;

/// Whether this declaration was "used", meaning that a definition is
/// required.
unsigned Used : 1;

/// Whether this declaration was "referenced".
/// The difference with 'Used' is whether the reference appears in a
/// evaluated context or not, e.g. functions used in uninstantiated templates
/// are regarded as "referenced" but not "used".
unsigned Referenced : 1;

/// Whether this declaration is a top-level declaration (function,
/// global variable, etc.) that is lexically inside an objc container
/// definition.
unsigned TopLevelDeclInObjCContainer : 1;

/// Whether statistic collection is enabled.
static bool StatisticsEnabled;

315protected:
friend class ASTDeclReader;
friend class ASTDeclWriter;
friend class ASTNodeImporter;
friend class ASTReader;
friend class CXXClassMemberWrapper;
friend class LinkageComputer;
template<typename decl_type> friend class Redeclarable;

/// Access - Used by C++ decls for the access specifier.
// NOTE: VC++ treats enums as signed, avoid using the AccessSpecifier enum
unsigned Access : 2;

/// Whether this declaration was loaded from an AST file.
unsigned FromASTFile : 1;

/// IdentifierNamespace - This specifies what IDNS_* namespace this lives in.
unsigned IdentifierNamespace : 14;

/// If 0, we have not computed the linkage of this declaration.
/// Otherwise, it is the linkage + 1.
mutable unsigned CacheValidAndLinkage : 3;

/// Allocate memory for a deserialized declaration.
///
/// This routine must be used to allocate memory for any declaration that is
/// deserialized from a module file.
///
/// \param Size The size of the allocated object.
/// \param Ctx The context in which we will allocate memory.
/// \param ID The global ID of the deserialized declaration.
/// \param Extra The amount of extra space to allocate after the object.
void *operator new(std::size_t Size, const ASTContext &Ctx, unsigned ID,
                   std::size_t Extra = 0);

/// Allocate memory for a non-deserialized declaration.
void *operator new(std::size_t Size, const ASTContext &Ctx,
                   DeclContext *Parent, std::size_t Extra = 0);

354private:
bool AccessDeclContextSanity() const;

/// Get the module ownership kind to use for a local lexical child of \p DC,
/// which may be either a local or (rarely) an imported declaration.
static ModuleOwnershipKind getModuleOwnershipKindForChildOf(DeclContext *DC) {
  if (DC) {
    auto *D = cast<Decl>(DC);
    auto MOK = D->getModuleOwnershipKind();
    if (MOK != ModuleOwnershipKind::Unowned &&
        (!D->isFromASTFile() || D->hasLocalOwningModuleStorage()))
      return MOK;
    // If D is not local and we have no local module storage, then we don't
    // need to track module ownership at all.
  }
  return ModuleOwnershipKind::Unowned;
}

372public:
Decl() = delete;
Decl(const Decl&) = delete;
Decl(Decl &&) = delete;
Decl &operator=(const Decl&) = delete;
Decl &operator=(Decl&&) = delete;

379protected:
Decl(Kind DK, DeclContext *DC, SourceLocation L)
    : NextInContextAndBits(nullptr, getModuleOwnershipKindForChildOf(DC)),
      DeclCtx(DC), Loc(L), DeclKind(DK), InvalidDecl(false), HasAttrs(false),
      Implicit(false), Used(false), Referenced(false),
      TopLevelDeclInObjCContainer(false), Access(AS_none), FromASTFile(0),
      IdentifierNamespace(getIdentifierNamespaceForKind(DK)),
      CacheValidAndLinkage(0) {
  if (StatisticsEnabled) add(DK);
}

Decl(Kind DK, EmptyShell Empty)
    : DeclKind(DK), InvalidDecl(false), HasAttrs(false), Implicit(false),
      Used(false), Referenced(false), TopLevelDeclInObjCContainer(false),
      Access(AS_none), FromASTFile(0),
      IdentifierNamespace(getIdentifierNamespaceForKind(DK)),
      CacheValidAndLinkage(0) {
  if (StatisticsEnabled) add(DK);
}

virtual ~Decl();

/// Update a potentially out-of-date declaration.
void updateOutOfDate(IdentifierInfo &II) const;

Linkage getCachedLinkage() const {
  return Linkage(CacheValidAndLinkage - 1);
}

void setCachedLinkage(Linkage L) const {
  CacheValidAndLinkage = L + 1;
}

bool hasCachedLinkage() const {
  return CacheValidAndLinkage;
}

416public:
/// Source range that this declaration covers.
virtual SourceRange getSourceRange() const LLVM_READONLY__attribute__((__pure__)) {
  return SourceRange(getLocation(), getLocation());
}

SourceLocation getBeginLoc() const LLVM_READONLY__attribute__((__pure__)) {
  return getSourceRange().getBegin();
}

SourceLocation getEndLoc() const LLVM_READONLY__attribute__((__pure__)) {
  return getSourceRange().getEnd();
}

SourceLocation getLocation() const { return Loc; }
void setLocation(SourceLocation L) { Loc = L; }

Kind getKind() const { return static_cast<Kind>(DeclKind); }
const char *getDeclKindName() const;

Decl *getNextDeclInContext() { return NextInContextAndBits.getPointer(); }
const Decl *getNextDeclInContext() const {return NextInContextAndBits.getPointer();}

DeclContext *getDeclContext() {
  if (isInSemaDC())
    return getSemanticDC();
  return getMultipleDC()->SemanticDC;
}
const DeclContext *getDeclContext() const {
  return const_cast<Decl*>(this)->getDeclContext();
}

/// Find the innermost non-closure ancestor of this declaration,
/// walking up through blocks, lambdas, etc.  If that ancestor is
/// not a code context (!isFunctionOrMethod()), returns null.
///
/// A declaration may be its own non-closure context.
Decl *getNonClosureContext();
const Decl *getNonClosureContext() const {
  return const_cast<Decl*>(this)->getNonClosureContext();
}

TranslationUnitDecl *getTranslationUnitDecl();
const TranslationUnitDecl *getTranslationUnitDecl() const {
  return const_cast<Decl*>(this)->getTranslationUnitDecl();
}

bool isInAnonymousNamespace() const;

bool isInStdNamespace() const;

ASTContext &getASTContext() const LLVM_READONLY__attribute__((__pure__));

/// Helper to get the language options from the ASTContext.
/// Defined out of line to avoid depending on ASTContext.h.
const LangOptions &getLangOpts() const LLVM_READONLY__attribute__((__pure__));

void setAccess(AccessSpecifier AS) {
  Access = AS;
  assert(AccessDeclContextSanity())((void)0);
}

AccessSpecifier getAccess() const {
  assert(AccessDeclContextSanity())((void)0);
  return AccessSpecifier(Access);
}

/// Retrieve the access specifier for this declaration, even though
/// it may not yet have been properly set.
AccessSpecifier getAccessUnsafe() const {
  return AccessSpecifier(Access);
}

bool hasAttrs() const { return HasAttrs; }

void setAttrs(const AttrVec& Attrs) {
  return setAttrsImpl(Attrs, getASTContext());
}

AttrVec &getAttrs() {
  return const_cast<AttrVec&>(const_cast<const Decl*>(this)->getAttrs());
}

const AttrVec &getAttrs() const;
void dropAttrs();
void addAttr(Attr *A);

using attr_iterator = AttrVec::const_iterator;
using attr_range = llvm::iterator_range<attr_iterator>;

attr_range attrs() const {
  return attr_range(attr_begin(), attr_end());
}

attr_iterator attr_begin() const {
  return hasAttrs() ? getAttrs().begin() : nullptr;
}
attr_iterator attr_end() const {
  return hasAttrs() ? getAttrs().end() : nullptr;
}

template <typename T>
void dropAttr() {
  if (!HasAttrs) return;

  AttrVec &Vec = getAttrs();
  llvm::erase_if(Vec, [](Attr *A) { return isa<T>(A); });

  if (Vec.empty())
    HasAttrs = false;
}

template <typename T>
llvm::iterator_range<specific_attr_iterator<T>> specific_attrs() const {
  return llvm::make_range(specific_attr_begin<T>(), specific_attr_end<T>());
}

template <typename T>
specific_attr_iterator<T> specific_attr_begin() const {
  return specific_attr_iterator<T>(attr_begin());
}

template <typename T>
specific_attr_iterator<T> specific_attr_end() const {
  return specific_attr_iterator<T>(attr_end());
}

template<typename T> T *getAttr() const {
  return hasAttrs() ? getSpecificAttr<T>(getAttrs()) : nullptr;
}

template<typename T> bool hasAttr() const {
  return hasAttrs() && hasSpecificAttr<T>(getAttrs());
}

/// getMaxAlignment - return the maximum alignment specified by attributes
/// on this decl, 0 if there are none.
unsigned getMaxAlignment() const;

/// setInvalidDecl - Indicates the Decl had a semantic error. This
/// allows for graceful error recovery.
void setInvalidDecl(bool Invalid = true);
bool isInvalidDecl() const { return (bool) InvalidDecl; }

/// isImplicit - Indicates whether the declaration was implicitly
/// generated by the implementation. If false, this declaration
/// was written explicitly in the source code.
bool isImplicit() const { return Implicit; }
void setImplicit(bool I = true) { Implicit = I; }

/// Whether *any* (re-)declaration of the entity was used, meaning that
/// a definition is required.
///
/// \param CheckUsedAttr When true, also consider the "used" attribute
/// (in addition to the "used" bit set by \c setUsed()) when determining
/// whether the function is used.
bool isUsed(bool CheckUsedAttr = true) const;

/// Set whether the declaration is used, in the sense of odr-use.
///
/// This should only be used immediately after creating a declaration.
/// It intentionally doesn't notify any listeners.
void setIsUsed() { getCanonicalDecl()->Used = true; }

/// Mark the declaration used, in the sense of odr-use.
///
/// This notifies any mutation listeners in addition to setting a bit
/// indicating the declaration is used.
void markUsed(ASTContext &C);

/// Whether any declaration of this entity was referenced.
bool isReferenced() const;

/// Whether this declaration was referenced. This should not be relied
/// upon for anything other than debugging.
bool isThisDeclarationReferenced() const { return Referenced; }

void setReferenced(bool R = true) { Referenced = R; }

/// Whether this declaration is a top-level declaration (function,
/// global variable, etc.) that is lexically inside an objc container
/// definition.
bool isTopLevelDeclInObjCContainer() const {
  return TopLevelDeclInObjCContainer;
}

void setTopLevelDeclInObjCContainer(bool V = true) {
  TopLevelDeclInObjCContainer = V;
}

/// Looks on this and related declarations for an applicable
/// external source symbol attribute.
ExternalSourceSymbolAttr *getExternalSourceSymbolAttr() const;

/// Whether this declaration was marked as being private to the
/// module in which it was defined.
bool isModulePrivate() const {
  return getModuleOwnershipKind() == ModuleOwnershipKind::ModulePrivate;
}

/// Return true if this declaration has an attribute which acts as
/// definition of the entity, such as 'alias' or 'ifunc'.
bool hasDefiningAttr() const;

/// Return this declaration's defining attribute if it has one.
const Attr *getDefiningAttr() const;

623protected:
/// Specify that this declaration was marked as being private
/// to the module in which it was defined.
void setModulePrivate() {
  // The module-private specifier has no effect on unowned declarations.
  // FIXME: We should track this in some way for source fidelity.
  if (getModuleOwnershipKind() == ModuleOwnershipKind::Unowned)
    return;
  setModuleOwnershipKind(ModuleOwnershipKind::ModulePrivate);
}

634public:
/// Set the FromASTFile flag. This indicates that this declaration
/// was deserialized and not parsed from source code and enables
/// features such as module ownership information.
void setFromASTFile() {
  FromASTFile = true;
}

/// Set the owning module ID.  This may only be called for
/// deserialized Decls.
void setOwningModuleID(unsigned ID) {
  assert(isFromASTFile() && "Only works on a deserialized declaration")((void)0);
  *((unsigned*)this - 2) = ID;
}

649public:
/// Determine the availability of the given declaration.
///
/// This routine will determine the most restrictive availability of
/// the given declaration (e.g., preferring 'unavailable' to
/// 'deprecated').
///
/// \param Message If non-NULL and the result is not \c
/// AR_Available, will be set to a (possibly empty) message
/// describing why the declaration has not been introduced, is
/// deprecated, or is unavailable.
///
/// \param EnclosingVersion The version to compare with. If empty, assume the
/// deployment target version.
///
/// \param RealizedPlatform If non-NULL and the availability result is found
/// in an available attribute it will set to the platform which is written in
/// the available attribute.
AvailabilityResult
getAvailability(std::string *Message = nullptr,
                VersionTuple EnclosingVersion = VersionTuple(),
                StringRef *RealizedPlatform = nullptr) const;

/// Retrieve the version of the target platform in which this
/// declaration was introduced.
///
/// \returns An empty version tuple if this declaration has no 'introduced'
/// availability attributes, or the version tuple that's specified in the
/// attribute otherwise.
VersionTuple getVersionIntroduced() const;

/// Determine whether this declaration is marked 'deprecated'.
///
/// \param Message If non-NULL and the declaration is deprecated,
/// this will be set to the message describing why the declaration
/// was deprecated (which may be empty).
bool isDeprecated(std::string *Message = nullptr) const {
  return getAvailability(Message) == AR_Deprecated;
}

/// Determine whether this declaration is marked 'unavailable'.
///
/// \param Message If non-NULL and the declaration is unavailable,
/// this will be set to the message describing why the declaration
/// was made unavailable (which may be empty).
bool isUnavailable(std::string *Message = nullptr) const {
  return getAvailability(Message) == AR_Unavailable;
}

/// Determine whether this is a weak-imported symbol.
///
/// Weak-imported symbols are typically marked with the
/// 'weak_import' attribute, but may also be marked with an
/// 'availability' attribute where we're targing a platform prior to
/// the introduction of this feature.
bool isWeakImported() const;

/// Determines whether this symbol can be weak-imported,
/// e.g., whether it would be well-formed to add the weak_import
/// attribute.
///
/// \param IsDefinition Set to \c true to indicate that this
/// declaration cannot be weak-imported because it has a definition.
bool canBeWeakImported(bool &IsDefinition) const;

/// Determine whether this declaration came from an AST file (such as
/// a precompiled header or module) rather than having been parsed.
bool isFromASTFile() const { return FromASTFile; }

/// Retrieve the global declaration ID associated with this
/// declaration, which specifies where this Decl was loaded from.
unsigned getGlobalID() const {
  if (isFromASTFile())
    return *((const unsigned*)this - 1);
  return 0;
}

/// Retrieve the global ID of the module that owns this particular
/// declaration.
unsigned getOwningModuleID() const {
  if (isFromASTFile())
    return *((const unsigned*)this - 2);
  return 0;
}

734private:
Module *getOwningModuleSlow() const;

737protected:
bool hasLocalOwningModuleStorage() const;

740public:
/// Get the imported owning module, if this decl is from an imported
/// (non-local) module.
Module *getImportedOwningModule() const {
  if (!isFromASTFile() || !hasOwningModule())
    return nullptr;

  return getOwningModuleSlow();
}

/// Get the local owning module, if known. Returns nullptr if owner is
/// not yet known or declaration is not from a module.
Module *getLocalOwningModule() const {
  if (isFromASTFile() || !hasOwningModule())
    return nullptr;

  assert(hasLocalOwningModuleStorage() &&((void)0)
         "owned local decl but no local module storage")((void)0);
  return reinterpret_cast<Module *const *>(this)[-1];
}
void setLocalOwningModule(Module *M) {
  assert(!isFromASTFile() && hasOwningModule() &&((void)0)
         hasLocalOwningModuleStorage() &&((void)0)
         "should not have a cached owning module")((void)0);
  reinterpret_cast<Module **>(this)[-1] = M;
}

/// Is this declaration owned by some module?
bool hasOwningModule() const {
  return getModuleOwnershipKind() != ModuleOwnershipKind::Unowned;
}

/// Get the module that owns this declaration (for visibility purposes).
Module *getOwningModule() const {
  return isFromASTFile() ? getImportedOwningModule() : getLocalOwningModule();
}

/// Get the module that owns this declaration for linkage purposes.
/// There only ever is such a module under the C++ Modules TS.
///
/// \param IgnoreLinkage Ignore the linkage of the entity; assume that
/// all declarations in a global module fragment are unowned.
Module *getOwningModuleForLinkage(bool IgnoreLinkage = false) const;

/// Determine whether this declaration is definitely visible to name lookup,
/// independent of whether the owning module is visible.
/// Note: The declaration may be visible even if this returns \c false if the
/// owning module is visible within the query context. This is a low-level
/// helper function; most code should be calling Sema::isVisible() instead.
bool isUnconditionallyVisible() const {
  return (int)getModuleOwnershipKind() <= (int)ModuleOwnershipKind::Visible;
}

/// Set that this declaration is globally visible, even if it came from a
/// module that is not visible.
void setVisibleDespiteOwningModule() {
  if (!isUnconditionallyVisible())
    setModuleOwnershipKind(ModuleOwnershipKind::Visible);
}

/// Get the kind of module ownership for this declaration.
ModuleOwnershipKind getModuleOwnershipKind() const {
  return NextInContextAndBits.getInt();
}

/// Set whether this declaration is hidden from name lookup.
void setModuleOwnershipKind(ModuleOwnershipKind MOK) {
  assert(!(getModuleOwnershipKind() == ModuleOwnershipKind::Unowned &&((void)0)
           MOK != ModuleOwnershipKind::Unowned && !isFromASTFile() &&((void)0)
           !hasLocalOwningModuleStorage()) &&((void)0)
         "no storage available for owning module for this declaration")((void)0);
  NextInContextAndBits.setInt(MOK);
}

unsigned getIdentifierNamespace() const {
  return IdentifierNamespace;
}

bool isInIdentifierNamespace(unsigned NS) const {
  return getIdentifierNamespace() & NS;
}

static unsigned getIdentifierNamespaceForKind(Kind DK);

bool hasTagIdentifierNamespace() const {
  return isTagIdentifierNamespace(getIdentifierNamespace());
}

static bool isTagIdentifierNamespace(unsigned NS) {
  // TagDecls have Tag and Type set and may also have TagFriend.
  return (NS & ~IDNS_TagFriend) == (IDNS_Tag | IDNS_Type);
}

/// getLexicalDeclContext - The declaration context where this Decl was
/// lexically declared (LexicalDC). May be different from
/// getDeclContext() (SemanticDC).
/// e.g.:
///
///   namespace A {
///      void f(); // SemanticDC == LexicalDC == 'namespace A'
///   }
///   void A::f(); // SemanticDC == namespace 'A'
///                // LexicalDC == global namespace
DeclContext *getLexicalDeclContext() {
  if (isInSemaDC())
    return getSemanticDC();
  return getMultipleDC()->LexicalDC;
}
const DeclContext *getLexicalDeclContext() const {
  return const_cast<Decl*>(this)->getLexicalDeclContext();
}

/// Determine whether this declaration is declared out of line (outside its
/// semantic context).
virtual bool isOutOfLine() const;

/// setDeclContext - Set both the semantic and lexical DeclContext
/// to DC.
void setDeclContext(DeclContext *DC);

void setLexicalDeclContext(DeclContext *DC);

/// Determine whether this declaration is a templated entity (whether it is
// within the scope of a template parameter).
bool isTemplated() const;

/// Determine the number of levels of template parameter surrounding this
/// declaration.
unsigned getTemplateDepth() const;

/// isDefinedOutsideFunctionOrMethod - This predicate returns true if this
/// scoped decl is defined outside the current function or method.  This is
/// roughly global variables and functions, but also handles enums (which
/// could be defined inside or outside a function etc).
bool isDefinedOutsideFunctionOrMethod() const {
  return getParentFunctionOrMethod() == nullptr;
}

/// Determine whether a substitution into this declaration would occur as
/// part of a substitution into a dependent local scope. Such a substitution
/// transitively substitutes into all constructs nested within this
/// declaration.
///
/// This recognizes non-defining declarations as well as members of local
/// classes and lambdas:
/// \code
///     template<typename T> void foo() { void bar(); }
///     template<typename T> void foo2() { class ABC { void bar(); }; }
///     template<typename T> inline int x = [](){ return 0; }();
/// \endcode
bool isInLocalScopeForInstantiation() const;

/// If this decl is defined inside a function/method/block it returns
/// the corresponding DeclContext, otherwise it returns null.
const DeclContext *getParentFunctionOrMethod() const;
DeclContext *getParentFunctionOrMethod() {
  return const_cast<DeclContext*>(
                  const_cast<const Decl*>(this)->getParentFunctionOrMethod());
}

/// Retrieves the "canonical" declaration of the given declaration.
virtual Decl *getCanonicalDecl() { return this; }
const Decl *getCanonicalDecl() const {
  return const_cast<Decl*>(this)->getCanonicalDecl();
}

/// Whether this particular Decl is a canonical one.
bool isCanonicalDecl() const { return getCanonicalDecl() == this; }

909protected:
/// Returns the next redeclaration or itself if this is the only decl.
///
/// Decl subclasses that can be redeclared should override this method so that
/// Decl::redecl_iterator can iterate over them.
virtual Decl *getNextRedeclarationImpl() { return this; }

/// Implementation of getPreviousDecl(), to be overridden by any
/// subclass that has a redeclaration chain.
virtual Decl *getPreviousDeclImpl() { return nullptr; }

/// Implementation of getMostRecentDecl(), to be overridden by any
/// subclass that has a redeclaration chain.
virtual Decl *getMostRecentDeclImpl() { return this; }

924public:
/// Iterates through all the redeclarations of the same decl.
class redecl_iterator {
  /// Current - The current declaration.
  Decl *Current = nullptr;
  Decl *Starter;

public:
  using value_type = Decl *;
  using reference = const value_type &;
  using pointer = const value_type *;
  using iterator_category = std::forward_iterator_tag;
  using difference_type = std::ptrdiff_t;

  redecl_iterator() = default;
  explicit redecl_iterator(Decl *C) : Current(C), Starter(C) {}

  reference operator*() const { return Current; }
  value_type operator->() const { return Current; }

  redecl_iterator& operator++() {
    assert(Current && "Advancing while iterator has reached end")((void)0);
    // Get either previous decl or latest decl.
    Decl *Next = Current->getNextRedeclarationImpl();
    assert(Next && "Should return next redeclaration or itself, never null!")((void)0);
    Current = (Next != Starter) ? Next : nullptr;
    return *this;
  }

  redecl_iterator operator++(int) {
    redecl_iterator tmp(*this);
    ++(*this);
    return tmp;
  }

  friend bool operator==(redecl_iterator x, redecl_iterator y) {
    return x.Current == y.Current;
  }

  friend bool operator!=(redecl_iterator x, redecl_iterator y) {
    return x.Current != y.Current;
  }
};

using redecl_range = llvm::iterator_range<redecl_iterator>;

/// Returns an iterator range for all the redeclarations of the same
/// decl. It will iterate at least once (when this decl is the only one).
redecl_range redecls() const {
  return redecl_range(redecls_begin(), redecls_end());
}

redecl_iterator redecls_begin() const {
  return redecl_iterator(const_cast<Decl *>(this));
}

redecl_iterator redecls_end() const { return redecl_iterator(); }

/// Retrieve the previous declaration that declares the same entity
/// as this declaration, or NULL if there is no previous declaration.
Decl *getPreviousDecl() { return getPreviousDeclImpl(); }

/// Retrieve the previous declaration that declares the same entity
/// as this declaration, or NULL if there is no previous declaration.
const Decl *getPreviousDecl() const {
  return const_cast<Decl *>(this)->getPreviousDeclImpl();
}

/// True if this is the first declaration in its redeclaration chain.
bool isFirstDecl() const {
  return getPreviousDecl() == nullptr;
}

/// Retrieve the most recent declaration that declares the same entity
/// as this declaration (which may be this declaration).
Decl *getMostRecentDecl() { return getMostRecentDeclImpl(); }

/// Retrieve the most recent declaration that declares the same entity
/// as this declaration (which may be this declaration).
const Decl *getMostRecentDecl() const {
  return const_cast<Decl *>(this)->getMostRecentDeclImpl();
}

/// getBody - If this Decl represents a declaration for a body of code,
///  such as a function or method definition, this method returns the
///  top-level Stmt* of that body.  Otherwise this method returns null.
virtual Stmt* getBody() const { return nullptr; }

/// Returns true if this \c Decl represents a declaration for a body of
/// code, such as a function or method definition.
/// Note that \c hasBody can also return true if any redeclaration of this
/// \c Decl represents a declaration for a body of code.
virtual bool hasBody() const { return getBody() != nullptr; }

/// getBodyRBrace - Gets the right brace of the body, if a body exists.
/// This works whether the body is a CompoundStmt or a CXXTryStmt.
SourceLocation getBodyRBrace() const;

// global temp stats (until we have a per-module visitor)
static void add(Kind k);
static void EnableStatistics();
static void PrintStats();

/// isTemplateParameter - Determines whether this declaration is a
/// template parameter.
bool isTemplateParameter() const;

/// isTemplateParameter - Determines whether this declaration is a
/// template parameter pack.
bool isTemplateParameterPack() const;

/// Whether this declaration is a parameter pack.
bool isParameterPack() const;

/// returns true if this declaration is a template
bool isTemplateDecl() const;

/// Whether this declaration is a function or function template.
bool isFunctionOrFunctionTemplate() const {
  return (DeclKind >= Decl::firstFunction &&
          DeclKind <= Decl::lastFunction) ||
         DeclKind == FunctionTemplate;
}

/// If this is a declaration that describes some template, this
/// method returns that template declaration.
///
/// Note that this returns nullptr for partial specializations, because they
/// are not modeled as TemplateDecls. Use getDescribedTemplateParams to handle
/// those cases.
TemplateDecl *getDescribedTemplate() const;

/// If this is a declaration that describes some template or partial
/// specialization, this returns the corresponding template parameter list.
const TemplateParameterList *getDescribedTemplateParams() const;

/// Returns the function itself, or the templated function if this is a
/// function template.
FunctionDecl *getAsFunction() LLVM_READONLY__attribute__((__pure__));

const FunctionDecl *getAsFunction() const {
  return const_cast<Decl *>(this)->getAsFunction();
}

/// Changes the namespace of this declaration to reflect that it's
/// a function-local extern declaration.
///
/// These declarations appear in the lexical context of the extern
/// declaration, but in the semantic context of the enclosing namespace
/// scope.
void setLocalExternDecl() {
  Decl *Prev = getPreviousDecl();
  IdentifierNamespace &= ~IDNS_Ordinary;

  // It's OK for the declaration to still have the "invisible friend" flag or
  // the "conflicts with tag declarations in this scope" flag for the outer
  // scope.
  assert((IdentifierNamespace & ~(IDNS_OrdinaryFriend | IDNS_Tag)) == 0 &&((void)0)
         "namespace is not ordinary")((void)0);

  IdentifierNamespace |= IDNS_LocalExtern;
  if (Prev && Prev->getIdentifierNamespace() & IDNS_Ordinary)
    IdentifierNamespace |= IDNS_Ordinary;
}

/// Determine whether this is a block-scope declaration with linkage.
/// This will either be a local variable declaration declared 'extern', or a
/// local function declaration.
bool isLocalExternDecl() {
  return IdentifierNamespace & IDNS_LocalExtern;
}

/// Changes the namespace of this declaration to reflect that it's
/// the object of a friend declaration.
///
/// These declarations appear in the lexical context of the friending
/// class, but in the semantic context of the actual entity.  This property
/// applies only to a specific decl object;  other redeclarations of the
/// same entity may not (and probably don't) share this property.
void setObjectOfFriendDecl(bool PerformFriendInjection = false) {
  unsigned OldNS = IdentifierNamespace;
  assert((OldNS & (IDNS_Tag | IDNS_Ordinary |((void)0)
                   IDNS_TagFriend | IDNS_OrdinaryFriend |((void)0)
                   IDNS_LocalExtern | IDNS_NonMemberOperator)) &&((void)0)
         "namespace includes neither ordinary nor tag")((void)0);
  assert(!(OldNS & ~(IDNS_Tag | IDNS_Ordinary | IDNS_Type |((void)0)
                     IDNS_TagFriend | IDNS_OrdinaryFriend |((void)0)
                     IDNS_LocalExtern | IDNS_NonMemberOperator)) &&((void)0)
         "namespace includes other than ordinary or tag")((void)0);

  Decl *Prev = getPreviousDecl();
  IdentifierNamespace &= ~(IDNS_Ordinary | IDNS_Tag | IDNS_Type);

  if (OldNS & (IDNS_Tag | IDNS_TagFriend)) {
    IdentifierNamespace |= IDNS_TagFriend;
    if (PerformFriendInjection ||
        (Prev && Prev->getIdentifierNamespace() & IDNS_Tag))
      IdentifierNamespace |= IDNS_Tag | IDNS_Type;
  }

  if (OldNS & (IDNS_Ordinary | IDNS_OrdinaryFriend |
               IDNS_LocalExtern | IDNS_NonMemberOperator)) {
    IdentifierNamespace |= IDNS_OrdinaryFriend;
    if (PerformFriendInjection ||
        (Prev && Prev->getIdentifierNamespace() & IDNS_Ordinary))
      IdentifierNamespace |= IDNS_Ordinary;
  }
}

enum FriendObjectKind {
  FOK_None,      ///< Not a friend object.
  FOK_Declared,  ///< A friend of a previously-declared entity.
  FOK_Undeclared ///< A friend of a previously-undeclared entity.
};

/// Determines whether this declaration is the object of a
/// friend declaration and, if so, what kind.
///
/// There is currently no direct way to find the associated FriendDecl.
FriendObjectKind getFriendObjectKind() const {
  unsigned mask =
      (IdentifierNamespace & (IDNS_TagFriend | IDNS_OrdinaryFriend));
  if (!mask) return FOK_None;
  return (IdentifierNamespace & (IDNS_Tag | IDNS_Ordinary) ? FOK_Declared
                                                           : FOK_Undeclared);
}

/// Specifies that this declaration is a C++ overloaded non-member.
void setNonMemberOperator() {
  assert(getKind() == Function || getKind() == FunctionTemplate)((void)0);
  assert((IdentifierNamespace & IDNS_Ordinary) &&((void)0)
         "visible non-member operators should be in ordinary namespace")((void)0);
  IdentifierNamespace |= IDNS_NonMemberOperator;
}

static bool classofKind(Kind K) { return true; }
static DeclContext *castToDeclContext(const Decl *);
static Decl *castFromDeclContext(const DeclContext *);

void print(raw_ostream &Out, unsigned Indentation = 0,
           bool PrintInstantiation = false) const;
void print(raw_ostream &Out, const PrintingPolicy &Policy,
           unsigned Indentation = 0, bool PrintInstantiation = false) const;
static void printGroup(Decl** Begin, unsigned NumDecls,
                       raw_ostream &Out, const PrintingPolicy &Policy,
                       unsigned Indentation = 0);

// Debuggers don't usually respect default arguments.
void dump() const;

// Same as dump(), but forces color printing.
void dumpColor() const;

void dump(raw_ostream &Out, bool Deserialize = false,
          ASTDumpOutputFormat OutputFormat = ADOF_Default) const;

/// \return Unique reproducible object identifier
int64_t getID() const;

/// Looks through the Decl's underlying type to extract a FunctionType
/// when possible. Will return null if the type underlying the Decl does not
/// have a FunctionType.
const FunctionType *getFunctionType(bool BlocksToo = true) const;

1188private:
void setAttrsImpl(const AttrVec& Attrs, ASTContext &Ctx);
void setDeclContextsImpl(DeclContext *SemaDC, DeclContext *LexicalDC,
                         ASTContext &Ctx);

1193protected:
ASTMutationListener *getASTMutationListener() const;
1195};

1197/// Determine whether two declarations declare the same entity.
1198inline bool declaresSameEntity(const Decl *D1, const Decl *D2) {
if (!D1 || !D2)
  return false;

if (D1 == D2)
  return true;

return D1->getCanonicalDecl() == D2->getCanonicalDecl();
1206}

1208/// PrettyStackTraceDecl - If a crash occurs, indicate that it happened when
1209/// doing something to a specific decl.
1210class PrettyStackTraceDecl : public llvm::PrettyStackTraceEntry {
const Decl *TheDecl;
SourceLocation Loc;
SourceManager &SM;
const char *Message;

1216public:
PrettyStackTraceDecl(const Decl *theDecl, SourceLocation L,
                     SourceManager &sm, const char *Msg)
    : TheDecl(theDecl), Loc(L), SM(sm), Message(Msg) {}

void print(raw_ostream &OS) const override;
1222};
1223} // namespace clang

1225// Required to determine the layout of the PointerUnion<NamedDecl*> before
1226// seeing the NamedDecl definition being first used in DeclListNode::operator*.
1227namespace llvm {
template <> struct PointerLikeTypeTraits<::clang::NamedDecl *> {
  static inline void *getAsVoidPointer(::clang::NamedDecl *P) { return P; }
  static inline ::clang::NamedDecl *getFromVoidPointer(void *P) {
    return static_cast<::clang::NamedDecl *>(P);
  }
  static constexpr int NumLowBitsAvailable = 3;
};
1235}

1237namespace clang {
1238/// A list storing NamedDecls in the lookup tables.
1239class DeclListNode {
friend class ASTContext; // allocate, deallocate nodes.
friend class StoredDeclsList;
1242public:
using Decls = llvm::PointerUnion<NamedDecl*, DeclListNode*>;
class iterator {
  friend class DeclContextLookupResult;
  friend class StoredDeclsList;

  Decls Ptr;
  iterator(Decls Node) : Ptr(Node) { }
public:
  using difference_type = ptrdiff_t;
  using value_type = NamedDecl*;
  using pointer = void;
  using reference = value_type;
  using iterator_category = std::forward_iterator_tag;

  iterator() = default;

  reference operator*() const {
    assert(Ptr && "dereferencing end() iterator")((void)0);
    if (DeclListNode *CurNode = Ptr.dyn_cast<DeclListNode*>())
      return CurNode->D;
    return Ptr.get<NamedDecl*>();
  }
  void operator->() const { } // Unsupported.
  bool operator==(const iterator &X) const { return Ptr == X.Ptr; }
  bool operator!=(const iterator &X) const { return Ptr != X.Ptr; }
  inline iterator &operator++() { // ++It
    assert(!Ptr.isNull() && "Advancing empty iterator")((void)0);

    if (DeclListNode *CurNode = Ptr.dyn_cast<DeclListNode*>())
      Ptr = CurNode->Rest;
    else
      Ptr = nullptr;
    return *this;
  }
  iterator operator++(int) { // It++
    iterator temp = *this;
    ++(*this);
    return temp;
  }
  // Enables the pattern for (iterator I =..., E = I.end(); I != E; ++I)
  iterator end() { return iterator(); }
};
1285private:
NamedDecl *D = nullptr;
Decls Rest = nullptr;
DeclListNode(NamedDecl *ND) : D(ND) {}
1289};

1291/// The results of name lookup within a DeclContext.
1292class DeclContextLookupResult {
using Decls = DeclListNode::Decls;

/// When in collection form, this is what the Data pointer points to.
Decls Result;

1298public:
DeclContextLookupResult() = default;
DeclContextLookupResult(Decls Result) : Result(Result) {}

using iterator = DeclListNode::iterator;
using const_iterator = iterator;
using reference = iterator::reference;

iterator begin() { return iterator(Result); }
iterator end() { return iterator(); }
const_iterator begin() const {
  return const_cast<DeclContextLookupResult*>(this)->begin();
}
const_iterator end() const { return iterator(); }

bool empty() const { return Result.isNull();  }
bool isSingleResult() const { return Result.dyn_cast<NamedDecl*>(); }
reference front() const { return *begin(); }

// Find the first declaration of the given type in the list. Note that this
// is not in general the earliest-declared declaration, and should only be
// used when it's not possible for there to be more than one match or where
// it doesn't matter which one is found.
template<class T> T *find_first() const {
  for (auto *D : *this)
    if (T *Decl = dyn_cast<T>(D))
      return Decl;

  return nullptr;
}
1328};

1330/// DeclContext - This is used only as base class of specific decl types that
1331/// can act as declaration contexts. These decls are (only the top classes
1332/// that directly derive from DeclContext are mentioned, not their subclasses):
1333///
1334///   TranslationUnitDecl
1335///   ExternCContext
1336///   NamespaceDecl
1337///   TagDecl
1338///   OMPDeclareReductionDecl
1339///   OMPDeclareMapperDecl
1340///   FunctionDecl
1341///   ObjCMethodDecl
1342///   ObjCContainerDecl
1343///   LinkageSpecDecl
1344///   ExportDecl
1345///   BlockDecl
1346///   CapturedDecl
1347class DeclContext {
/// For makeDeclVisibleInContextImpl
friend class ASTDeclReader;
/// For reconcileExternalVisibleStorage, CreateStoredDeclsMap,
/// hasNeedToReconcileExternalVisibleStorage
friend class ExternalASTSource;
/// For CreateStoredDeclsMap
friend class DependentDiagnostic;
/// For hasNeedToReconcileExternalVisibleStorage,
/// hasLazyLocalLexicalLookups, hasLazyExternalLexicalLookups
friend class ASTWriter;

// We use uint64_t in the bit-fields below since some bit-fields
// cross the unsigned boundary and this breaks the packing.

/// Stores the bits used by DeclContext.
/// If modified NumDeclContextBit, the ctor of DeclContext and the accessor
/// methods in DeclContext should be updated appropriately.
class DeclContextBitfields {
  friend class DeclContext;
  /// DeclKind - This indicates which class this is.
  uint64_t DeclKind : 7;

  /// Whether this declaration context also has some external
  /// storage that contains additional declarations that are lexically
  /// part of this context.
  mutable uint64_t ExternalLexicalStorage : 1;

  /// Whether this declaration context also has some external
  /// storage that contains additional declarations that are visible
  /// in this context.
  mutable uint64_t ExternalVisibleStorage : 1;

  /// Whether this declaration context has had externally visible
  /// storage added since the last lookup. In this case, \c LookupPtr's
  /// invariant may not hold and needs to be fixed before we perform
  /// another lookup.
  mutable uint64_t NeedToReconcileExternalVisibleStorage : 1;

  /// If \c true, this context may have local lexical declarations
  /// that are missing from the lookup table.
  mutable uint64_t HasLazyLocalLexicalLookups : 1;

  /// If \c true, the external source may have lexical declarations
  /// that are missing from the lookup table.
  mutable uint64_t HasLazyExternalLexicalLookups : 1;

  /// If \c true, lookups should only return identifier from
  /// DeclContext scope (for example TranslationUnit). Used in
  /// LookupQualifiedName()
  mutable uint64_t UseQualifiedLookup : 1;
};

/// Number of bits in DeclContextBitfields.
enum { NumDeclContextBits = 13 };

/// Stores the bits used by TagDecl.
/// If modified NumTagDeclBits and the accessor
/// methods in TagDecl should be updated appropriately.
class TagDeclBitfields {
  friend class TagDecl;
  /// For the bits in DeclContextBitfields
  uint64_t : NumDeclContextBits;

  /// The TagKind enum.
  uint64_t TagDeclKind : 3;

  /// True if this is a definition ("struct foo {};"), false if it is a
  /// declaration ("struct foo;").  It is not considered a definition
  /// until the definition has been fully processed.
  uint64_t IsCompleteDefinition : 1;

  /// True if this is currently being defined.
  uint64_t IsBeingDefined : 1;

  /// True if this tag declaration is "embedded" (i.e., defined or declared
  /// for the very first time) in the syntax of a declarator.
  uint64_t IsEmbeddedInDeclarator : 1;

  /// True if this tag is free standing, e.g. "struct foo;".
  uint64_t IsFreeStanding : 1;

  /// Indicates whether it is possible for declarations of this kind
  /// to have an out-of-date definition.
  ///
  /// This option is only enabled when modules are enabled.
  uint64_t MayHaveOutOfDateDef : 1;

  /// Has the full definition of this type been required by a use somewhere in
  /// the TU.
  uint64_t IsCompleteDefinitionRequired : 1;
};

/// Number of non-inherited bits in TagDeclBitfields.
enum { NumTagDeclBits = 9 };

/// Stores the bits used by EnumDecl.
/// If modified NumEnumDeclBit and the accessor
/// methods in EnumDecl should be updated appropriately.
class EnumDeclBitfields {
  friend class EnumDecl;
  /// For the bits in DeclContextBitfields.
  uint64_t : NumDeclContextBits;
  /// For the bits in TagDeclBitfields.
  uint64_t : NumTagDeclBits;

  /// Width in bits required to store all the non-negative
  /// enumerators of this enum.
  uint64_t NumPositiveBits : 8;

  /// Width in bits required to store all the negative
  /// enumerators of this enum.
  uint64_t NumNegativeBits : 8;

  /// True if this tag declaration is a scoped enumeration. Only
  /// possible in C++11 mode.
  uint64_t IsScoped : 1;

  /// If this tag declaration is a scoped enum,
  /// then this is true if the scoped enum was declared using the class
  /// tag, false if it was declared with the struct tag. No meaning is
  /// associated if this tag declaration is not a scoped enum.
  uint64_t IsScopedUsingClassTag : 1;

  /// True if this is an enumeration with fixed underlying type. Only
  /// possible in C++11, Microsoft extensions, or Objective C mode.
  uint64_t IsFixed : 1;

  /// True if a valid hash is stored in ODRHash.
  uint64_t HasODRHash : 1;
};

/// Number of non-inherited bits in EnumDeclBitfields.
enum { NumEnumDeclBits = 20 };

/// Stores the bits used by RecordDecl.
/// If modified NumRecordDeclBits and the accessor
/// methods in RecordDecl should be updated appropriately.
class RecordDeclBitfields {
  friend class RecordDecl;
  /// For the bits in DeclContextBitfields.
  uint64_t : NumDeclContextBits;
  /// For the bits in TagDeclBitfields.
  uint64_t : NumTagDeclBits;

  /// This is true if this struct ends with a flexible
  /// array member (e.g. int X[]) or if this union contains a struct that does.
  /// If so, this cannot be contained in arrays or other structs as a member.
  uint64_t HasFlexibleArrayMember : 1;

  /// Whether this is the type of an anonymous struct or union.
  uint64_t AnonymousStructOrUnion : 1;

  /// This is true if this struct has at least one member
  /// containing an Objective-C object pointer type.
  uint64_t HasObjectMember : 1;

  /// This is true if struct has at least one member of
  /// 'volatile' type.
  uint64_t HasVolatileMember : 1;

  /// Whether the field declarations of this record have been loaded
  /// from external storage. To avoid unnecessary deserialization of
  /// methods/nested types we allow deserialization of just the fields
  /// when needed.
  mutable uint64_t LoadedFieldsFromExternalStorage : 1;

  /// Basic properties of non-trivial C structs.
  uint64_t NonTrivialToPrimitiveDefaultInitialize : 1;
  uint64_t NonTrivialToPrimitiveCopy : 1;
  uint64_t NonTrivialToPrimitiveDestroy : 1;

  /// The following bits indicate whether this is or contains a C union that
  /// is non-trivial to default-initialize, destruct, or copy. These bits
  /// imply the associated basic non-triviality predicates declared above.
  uint64_t HasNonTrivialToPrimitiveDefaultInitializeCUnion : 1;
  uint64_t HasNonTrivialToPrimitiveDestructCUnion : 1;
  uint64_t HasNonTrivialToPrimitiveCopyCUnion : 1;

  /// Indicates whether this struct is destroyed in the callee.
  uint64_t ParamDestroyedInCallee : 1;

  /// Represents the way this type is passed to a function.
  uint64_t ArgPassingRestrictions : 2;
};

/// Number of non-inherited bits in RecordDeclBitfields.
enum { NumRecordDeclBits = 14 };

/// Stores the bits used by OMPDeclareReductionDecl.
/// If modified NumOMPDeclareReductionDeclBits and the accessor
/// methods in OMPDeclareReductionDecl should be updated appropriately.
class OMPDeclareReductionDeclBitfields {
  friend class OMPDeclareReductionDecl;
  /// For the bits in DeclContextBitfields
  uint64_t : NumDeclContextBits;

  /// Kind of initializer,
  /// function call or omp_priv<init_expr> initializtion.
  uint64_t InitializerKind : 2;
};

/// Number of non-inherited bits in OMPDeclareReductionDeclBitfields.
enum { NumOMPDeclareReductionDeclBits = 2 };

/// Stores the bits used by FunctionDecl.
/// If modified NumFunctionDeclBits and the accessor
/// methods in FunctionDecl and CXXDeductionGuideDecl
/// (for IsCopyDeductionCandidate) should be updated appropriately.
class FunctionDeclBitfields {
  friend class FunctionDecl;
  /// For IsCopyDeductionCandidate
  friend class CXXDeductionGuideDecl;
  /// For the bits in DeclContextBitfields.
  uint64_t : NumDeclContextBits;

  uint64_t SClass : 3;
  uint64_t IsInline : 1;
  uint64_t IsInlineSpecified : 1;

  uint64_t IsVirtualAsWritten : 1;
  uint64_t IsPure : 1;
  uint64_t HasInheritedPrototype : 1;
  uint64_t HasWrittenPrototype : 1;
  uint64_t IsDeleted : 1;
  /// Used by CXXMethodDecl
  uint64_t IsTrivial : 1;

  /// This flag indicates whether this function is trivial for the purpose of
  /// calls. This is meaningful only when this function is a copy/move
  /// constructor or a destructor.
  uint64_t IsTrivialForCall : 1;

  uint64_t IsDefaulted : 1;
  uint64_t IsExplicitlyDefaulted : 1;
  uint64_t HasDefaultedFunctionInfo : 1;
  uint64_t HasImplicitReturnZero : 1;
  uint64_t IsLateTemplateParsed : 1;

  /// Kind of contexpr specifier as defined by ConstexprSpecKind.
  uint64_t ConstexprKind : 2;
  uint64_t InstantiationIsPending : 1;

  /// Indicates if the function uses __try.
  uint64_t UsesSEHTry : 1;

  /// Indicates if the function was a definition
  /// but its body was skipped.
  uint64_t HasSkippedBody : 1;

  /// Indicates if the function declaration will
  /// have a body, once we're done parsing it.
  uint64_t WillHaveBody : 1;

  /// Indicates that this function is a multiversioned
  /// function using attribute 'target'.
  uint64_t IsMultiVersion : 1;

  /// [C++17] Only used by CXXDeductionGuideDecl. Indicates that
  /// the Deduction Guide is the implicitly generated 'copy
  /// deduction candidate' (is used during overload resolution).
  uint64_t IsCopyDeductionCandidate : 1;

  /// Store the ODRHash after first calculation.
  uint64_t HasODRHash : 1;

  /// Indicates if the function uses Floating Point Constrained Intrinsics
  uint64_t UsesFPIntrin : 1;
};

/// Number of non-inherited bits in FunctionDeclBitfields.
enum { NumFunctionDeclBits = 27 };

/// Stores the bits used by CXXConstructorDecl. If modified
/// NumCXXConstructorDeclBits and the accessor
/// methods in CXXConstructorDecl should be updated appropriately.
class CXXConstructorDeclBitfields {
  friend class CXXConstructorDecl;
  /// For the bits in DeclContextBitfields.
  uint64_t : NumDeclContextBits;
  /// For the bits in FunctionDeclBitfields.
  uint64_t : NumFunctionDeclBits;

  /// 24 bits to fit in the remaining available space.
  /// Note that this makes CXXConstructorDeclBitfields take
  /// exactly 64 bits and thus the width of NumCtorInitializers
  /// will need to be shrunk if some bit is added to NumDeclContextBitfields,
  /// NumFunctionDeclBitfields or CXXConstructorDeclBitfields.
  uint64_t NumCtorInitializers : 21;
  uint64_t IsInheritingConstructor : 1;

  /// Whether this constructor has a trail-allocated explicit specifier.
  uint64_t HasTrailingExplicitSpecifier : 1;
  /// If this constructor does't have a trail-allocated explicit specifier.
  /// Whether this constructor is explicit specified.
  uint64_t IsSimpleExplicit : 1;
};

/// Number of non-inherited bits in CXXConstructorDeclBitfields.
enum {
  NumCXXConstructorDeclBits = 64 - NumDeclContextBits - NumFunctionDeclBits
};

/// Stores the bits used by ObjCMethodDecl.
/// If modified NumObjCMethodDeclBits and the accessor
/// methods in ObjCMethodDecl should be updated appropriately.
class ObjCMethodDeclBitfields {
  friend class ObjCMethodDecl;

  /// For the bits in DeclContextBitfields.
  uint64_t : NumDeclContextBits;

  /// The conventional meaning of this method; an ObjCMethodFamily.
  /// This is not serialized; instead, it is computed on demand and
  /// cached.
  mutable uint64_t Family : ObjCMethodFamilyBitWidth;

  /// instance (true) or class (false) method.
  uint64_t IsInstance : 1;
  uint64_t IsVariadic : 1;

  /// True if this method is the getter or setter for an explicit property.
  uint64_t IsPropertyAccessor : 1;

  /// True if this method is a synthesized property accessor stub.
  uint64_t IsSynthesizedAccessorStub : 1;

  /// Method has a definition.
  uint64_t IsDefined : 1;

  /// Method redeclaration in the same interface.
  uint64_t IsRedeclaration : 1;

  /// Is redeclared in the same interface.
  mutable uint64_t HasRedeclaration : 1;

  /// \@required/\@optional
  uint64_t DeclImplementation : 2;

  /// in, inout, etc.
  uint64_t objcDeclQualifier : 7;

  /// Indicates whether this method has a related result type.
  uint64_t RelatedResultType : 1;

  /// Whether the locations of the selector identifiers are in a
  /// "standard" position, a enum SelectorLocationsKind.
  uint64_t SelLocsKind : 2;

  /// Whether this method overrides any other in the class hierarchy.
  ///
  /// A method is said to override any method in the class's
  /// base classes, its protocols, or its categories' protocols, that has
  /// the same selector and is of the same kind (class or instance).
  /// A method in an implementation is not considered as overriding the same
  /// method in the interface or its categories.
  uint64_t IsOverriding : 1;

  /// Indicates if the method was a definition but its body was skipped.
  uint64_t HasSkippedBody : 1;
};

/// Number of non-inherited bits in ObjCMethodDeclBitfields.
enum { NumObjCMethodDeclBits = 24 };

/// Stores the bits used by ObjCContainerDecl.
/// If modified NumObjCContainerDeclBits and the accessor
/// methods in ObjCContainerDecl should be updated appropriately.
class ObjCContainerDeclBitfields {
  friend class ObjCContainerDecl;
  /// For the bits in DeclContextBitfields
  uint32_t : NumDeclContextBits;

  // Not a bitfield but this saves space.
  // Note that ObjCContainerDeclBitfields is full.
  SourceLocation AtStart;
};

/// Number of non-inherited bits in ObjCContainerDeclBitfields.
/// Note that here we rely on the fact that SourceLocation is 32 bits
/// wide. We check this with the static_assert in the ctor of DeclContext.
enum { NumObjCContainerDeclBits = 64 - NumDeclContextBits };

/// Stores the bits used by LinkageSpecDecl.
/// If modified NumLinkageSpecDeclBits and the accessor
/// methods in LinkageSpecDecl should be updated appropriately.
class LinkageSpecDeclBitfields {
  friend class LinkageSpecDecl;
  /// For the bits in DeclContextBitfields.
  uint64_t : NumDeclContextBits;

  /// The language for this linkage specification with values
  /// in the enum LinkageSpecDecl::LanguageIDs.
  uint64_t Language : 3;

  /// True if this linkage spec has braces.
  /// This is needed so that hasBraces() returns the correct result while the
  /// linkage spec body is being parsed.  Once RBraceLoc has been set this is
  /// not used, so it doesn't need to be serialized.
  uint64_t HasBraces : 1;
};

/// Number of non-inherited bits in LinkageSpecDeclBitfields.
enum { NumLinkageSpecDeclBits = 4 };

/// Stores the bits used by BlockDecl.
/// If modified NumBlockDeclBits and the accessor
/// methods in BlockDecl should be updated appropriately.
class BlockDeclBitfields {
  friend class BlockDecl;
  /// For the bits in DeclContextBitfields.
  uint64_t : NumDeclContextBits;

  uint64_t IsVariadic : 1;
  uint64_t CapturesCXXThis : 1;
  uint64_t BlockMissingReturnType : 1;
  uint64_t IsConversionFromLambda : 1;

  /// A bit that indicates this block is passed directly to a function as a
  /// non-escaping parameter.
  uint64_t DoesNotEscape : 1;

  /// A bit that indicates whether it's possible to avoid coying this block to
  /// the heap when it initializes or is assigned to a local variable with
  /// automatic storage.
  uint64_t CanAvoidCopyToHeap : 1;
};

/// Number of non-inherited bits in BlockDeclBitfields.
enum { NumBlockDeclBits = 5 };

/// Pointer to the data structure used to lookup declarations
/// within this context (or a DependentStoredDeclsMap if this is a
/// dependent context). We maintain the invariant that, if the map
/// contains an entry for a DeclarationName (and we haven't lazily
/// omitted anything), then it contains all relevant entries for that
/// name (modulo the hasExternalDecls() flag).
mutable StoredDeclsMap *LookupPtr = nullptr;

1786protected:
/// This anonymous union stores the bits belonging to DeclContext and classes
/// deriving from it. The goal is to use otherwise wasted
/// space in DeclContext to store data belonging to derived classes.
/// The space saved is especially significient when pointers are aligned
/// to 8 bytes. In this case due to alignment requirements we have a
/// little less than 8 bytes free in DeclContext which we can use.
/// We check that none of the classes in this union is larger than
/// 8 bytes with static_asserts in the ctor of DeclContext.
union {
  DeclContextBitfields DeclContextBits;
  TagDeclBitfields TagDeclBits;
  EnumDeclBitfields EnumDeclBits;
  RecordDeclBitfields RecordDeclBits;
  OMPDeclareReductionDeclBitfields OMPDeclareReductionDeclBits;
  FunctionDeclBitfields FunctionDeclBits;
  CXXConstructorDeclBitfields CXXConstructorDeclBits;
  ObjCMethodDeclBitfields ObjCMethodDeclBits;
  ObjCContainerDeclBitfields ObjCContainerDeclBits;
  LinkageSpecDeclBitfields LinkageSpecDeclBits;
  BlockDeclBitfields BlockDeclBits;

  static_assert(sizeof(DeclContextBitfields) <= 8,
                "DeclContextBitfields is larger than 8 bytes!");
  static_assert(sizeof(TagDeclBitfields) <= 8,
                "TagDeclBitfields is larger than 8 bytes!");
  static_assert(sizeof(EnumDeclBitfields) <= 8,
                "EnumDeclBitfields is larger than 8 bytes!");
  static_assert(sizeof(RecordDeclBitfields) <= 8,
                "RecordDeclBitfields is larger than 8 bytes!");
  static_assert(sizeof(OMPDeclareReductionDeclBitfields) <= 8,
                "OMPDeclareReductionDeclBitfields is larger than 8 bytes!");
  static_assert(sizeof(FunctionDeclBitfields) <= 8,
                "FunctionDeclBitfields is larger than 8 bytes!");
  static_assert(sizeof(CXXConstructorDeclBitfields) <= 8,
                "CXXConstructorDeclBitfields is larger than 8 bytes!");
  static_assert(sizeof(ObjCMethodDeclBitfields) <= 8,
                "ObjCMethodDeclBitfields is larger than 8 bytes!");
  static_assert(sizeof(ObjCContainerDeclBitfields) <= 8,
                "ObjCContainerDeclBitfields is larger than 8 bytes!");
  static_assert(sizeof(LinkageSpecDeclBitfields) <= 8,
                "LinkageSpecDeclBitfields is larger than 8 bytes!");
  static_assert(sizeof(BlockDeclBitfields) <= 8,
                "BlockDeclBitfields is larger than 8 bytes!");
};

/// FirstDecl - The first declaration stored within this declaration
/// context.
mutable Decl *FirstDecl = nullptr;

/// LastDecl - The last declaration stored within this declaration
/// context. FIXME: We could probably cache this value somewhere
/// outside of the DeclContext, to reduce the size of DeclContext by
/// another pointer.
mutable Decl *LastDecl = nullptr;

/// Build up a chain of declarations.
///
/// \returns the first/last pair of declarations.
static std::pair<Decl *, Decl *>
BuildDeclChain(ArrayRef<Decl*> Decls, bool FieldsAlreadyLoaded);

DeclContext(Decl::Kind K);

1850public:
~DeclContext();

Decl::Kind getDeclKind() const {
  return static_cast<Decl::Kind>(DeclContextBits.DeclKind);
}

const char *getDeclKindName() const;

/// getParent - Returns the containing DeclContext.
DeclContext *getParent() {
  return cast<Decl>(this)->getDeclContext();
}
const DeclContext *getParent() const {
  return const_cast<DeclContext*>(this)->getParent();
}

/// getLexicalParent - Returns the containing lexical DeclContext. May be
/// different from getParent, e.g.:
///
///   namespace A {
///      struct S;
///   }
///   struct A::S {}; // getParent() == namespace 'A'
///                   // getLexicalParent() == translation unit
///
DeclContext *getLexicalParent() {
  return cast<Decl>(this)->getLexicalDeclContext();
}
const DeclContext *getLexicalParent() const {
  return const_cast<DeclContext*>(this)->getLexicalParent();
}

DeclContext *getLookupParent();

const DeclContext *getLookupParent() const {
  return const_cast<DeclContext*>(this)->getLookupParent();
}

ASTContext &getParentASTContext() const {
  return cast<Decl>(this)->getASTContext();
}

bool isClosure() const { return getDeclKind() == Decl::Block; }

/// Return this DeclContext if it is a BlockDecl. Otherwise, return the
/// innermost enclosing BlockDecl or null if there are no enclosing blocks.
const BlockDecl *getInnermostBlockDecl() const;

bool isObjCContainer() const {
  switch (getDeclKind()) {
  case Decl::ObjCCategory:
  case Decl::ObjCCategoryImpl:
  case Decl::ObjCImplementation:
  case Decl::ObjCInterface:
  case Decl::ObjCProtocol:
    return true;
  default:
    return false;
  }
}

bool isFunctionOrMethod() const {
  switch (getDeclKind()) {
  case Decl::Block:
  case Decl::Captured:
  case Decl::ObjCMethod:
    return true;
  default:
    return getDeclKind() >= Decl::firstFunction &&
           getDeclKind() <= Decl::lastFunction;
  }
}

/// Test whether the context supports looking up names.
bool isLookupContext() const {
  return !isFunctionOrMethod() && getDeclKind() != Decl::LinkageSpec &&
         getDeclKind() != Decl::Export;
}

bool isFileContext() const {
  return getDeclKind() == Decl::TranslationUnit ||
         getDeclKind() == Decl::Namespace;
}

bool isTranslationUnit() const {
  return getDeclKind() == Decl::TranslationUnit;
}

bool isRecord() const {
  return getDeclKind() >= Decl::firstRecord &&
         getDeclKind() <= Decl::lastRecord;
}

bool isNamespace() const { return getDeclKind() == Decl::Namespace; }
15
←
Assuming the condition is true→
16
←
Returning the value 1, which participates in a condition later→

bool isStdNamespace() const;

bool isInlineNamespace() const;

/// Determines whether this context is dependent on a
/// template parameter.
bool isDependentContext() const;

/// isTransparentContext - Determines whether this context is a
/// "transparent" context, meaning that the members declared in this
/// context are semantically declared in the nearest enclosing
/// non-transparent (opaque) context but are lexically declared in
/// this context. For example, consider the enumerators of an
/// enumeration type:
/// @code
/// enum E {
///   Val1
/// };
/// @endcode
/// Here, E is a transparent context, so its enumerator (Val1) will
/// appear (semantically) that it is in the same context of E.
/// Examples of transparent contexts include: enumerations (except for
/// C++0x scoped enums), and C++ linkage specifications.
bool isTransparentContext() const;

/// Determines whether this context or some of its ancestors is a
/// linkage specification context that specifies C linkage.
bool isExternCContext() const;

/// Retrieve the nearest enclosing C linkage specification context.
const LinkageSpecDecl *getExternCContext() const;

/// Determines whether this context or some of its ancestors is a
/// linkage specification context that specifies C++ linkage.
bool isExternCXXContext() const;

/// Determine whether this declaration context is equivalent
/// to the declaration context DC.
bool Equals(const DeclContext *DC) const {
  return DC && this->getPrimaryContext() == DC->getPrimaryContext();
}

/// Determine whether this declaration context encloses the
/// declaration context DC.
bool Encloses(const DeclContext *DC) const;

/// Find the nearest non-closure ancestor of this context,
/// i.e. the innermost semantic parent of this context which is not
/// a closure.  A context may be its own non-closure ancestor.
Decl *getNonClosureAncestor();
const Decl *getNonClosureAncestor() const {
  return const_cast<DeclContext*>(this)->getNonClosureAncestor();
}

/// getPrimaryContext - There may be many different
/// declarations of the same entity (including forward declarations
/// of classes, multiple definitions of namespaces, etc.), each with
/// a different set of declarations. This routine returns the
/// "primary" DeclContext structure, which will contain the
/// information needed to perform name lookup into this context.
DeclContext *getPrimaryContext();
const DeclContext *getPrimaryContext() const {
  return const_cast<DeclContext*>(this)->getPrimaryContext();
}

/// getRedeclContext - Retrieve the context in which an entity conflicts with
/// other entities of the same name, or where it is a redeclaration if the
/// two entities are compatible. This skips through transparent contexts.
DeclContext *getRedeclContext();
const DeclContext *getRedeclContext() const {
  return const_cast<DeclContext *>(this)->getRedeclContext();
}

/// Retrieve the nearest enclosing namespace context.
DeclContext *getEnclosingNamespaceContext();
const DeclContext *getEnclosingNamespaceContext() const {
  return const_cast<DeclContext *>(this)->getEnclosingNamespaceContext();
}

/// Retrieve the outermost lexically enclosing record context.
RecordDecl *getOuterLexicalRecordContext();
const RecordDecl *getOuterLexicalRecordContext() const {
  return const_cast<DeclContext *>(this)->getOuterLexicalRecordContext();
}

/// Test if this context is part of the enclosing namespace set of
/// the context NS, as defined in C++0x [namespace.def]p9. If either context
/// isn't a namespace, this is equivalent to Equals().
///
/// The enclosing namespace set of a namespace is the namespace and, if it is
/// inline, its enclosing namespace, recursively.
bool InEnclosingNamespaceSetOf(const DeclContext *NS) const;

/// Collects all of the declaration contexts that are semantically
/// connected to this declaration context.
///
/// For declaration contexts that have multiple semantically connected but
/// syntactically distinct contexts, such as C++ namespaces, this routine
/// retrieves the complete set of such declaration contexts in source order.
/// For example, given:
///
/// \code
/// namespace N {
///   int x;
/// }
/// namespace N {
///   int y;
/// }
/// \endcode
///
/// The \c Contexts parameter will contain both definitions of N.
///
/// \param Contexts Will be cleared and set to the set of declaration
/// contexts that are semanticaly connected to this declaration context,
/// in source order, including this context (which may be the only result,
/// for non-namespace contexts).
void collectAllContexts(SmallVectorImpl<DeclContext *> &Contexts);

/// decl_iterator - Iterates through the declarations stored
/// within this context.
class decl_iterator {
  /// Current - The current declaration.
  Decl *Current = nullptr;

public:
  using value_type = Decl *;
  using reference = const value_type &;
  using pointer = const value_type *;
  using iterator_category = std::forward_iterator_tag;
  using difference_type = std::ptrdiff_t;

  decl_iterator() = default;
  explicit decl_iterator(Decl *C) : Current(C) {}

  reference operator*() const { return Current; }

  // This doesn't meet the iterator requirements, but it's convenient
  value_type operator->() const { return Current; }

  decl_iterator& operator++() {
    Current = Current->getNextDeclInContext();
    return *this;
  }

  decl_iterator operator++(int) {
    decl_iterator tmp(*this);
    ++(*this);
    return tmp;
  }

  friend bool operator==(decl_iterator x, decl_iterator y) {
    return x.Current == y.Current;
  }

  friend bool operator!=(decl_iterator x, decl_iterator y) {
    return x.Current != y.Current;
  }
};

using decl_range = llvm::iterator_range<decl_iterator>;

/// decls_begin/decls_end - Iterate over the declarations stored in
/// this context.
decl_range decls() const { return decl_range(decls_begin(), decls_end()); }
decl_iterator decls_begin() const;
decl_iterator decls_end() const { return decl_iterator(); }
bool decls_empty() const;

/// noload_decls_begin/end - Iterate over the declarations stored in this
/// context that are currently loaded; don't attempt to retrieve anything
/// from an external source.
decl_range noload_decls() const {
  return decl_range(noload_decls_begin(), noload_decls_end());
}
decl_iterator noload_decls_begin() const { return decl_iterator(FirstDecl); }
decl_iterator noload_decls_end() const { return decl_iterator(); }

/// specific_decl_iterator - Iterates over a subrange of
/// declarations stored in a DeclContext, providing only those that
/// are of type SpecificDecl (or a class derived from it). This
/// iterator is used, for example, to provide iteration over just
/// the fields within a RecordDecl (with SpecificDecl = FieldDecl).
template<typename SpecificDecl>
class specific_decl_iterator {
  /// Current - The current, underlying declaration iterator, which
  /// will either be NULL or will point to a declaration of
  /// type SpecificDecl.
  DeclContext::decl_iterator Current;

  /// SkipToNextDecl - Advances the current position up to the next
  /// declaration of type SpecificDecl that also meets the criteria
  /// required by Acceptable.
  void SkipToNextDecl() {
    while (*Current && !isa<SpecificDecl>(*Current))
      ++Current;
  }

public:
  using value_type = SpecificDecl *;
  // TODO: Add reference and pointer types (with some appropriate proxy type)
  // if we ever have a need for them.
  using reference = void;
  using pointer = void;
  using difference_type =
      std::iterator_traits<DeclContext::decl_iterator>::difference_type;
  using iterator_category = std::forward_iterator_tag;

  specific_decl_iterator() = default;

  /// specific_decl_iterator - Construct a new iterator over a
  /// subset of the declarations the range [C,
  /// end-of-declarations). If A is non-NULL, it is a pointer to a
  /// member function of SpecificDecl that should return true for
  /// all of the SpecificDecl instances that will be in the subset
  /// of iterators. For example, if you want Objective-C instance
  /// methods, SpecificDecl will be ObjCMethodDecl and A will be
  /// &ObjCMethodDecl::isInstanceMethod.
  explicit specific_decl_iterator(DeclContext::decl_iterator C) : Current(C) {
    SkipToNextDecl();
  }

  value_type operator*() const { return cast<SpecificDecl>(*Current); }

  // This doesn't meet the iterator requirements, but it's convenient
  value_type operator->() const { return **this; }

  specific_decl_iterator& operator++() {
    ++Current;
    SkipToNextDecl();
    return *this;
  }

  specific_decl_iterator operator++(int) {
    specific_decl_iterator tmp(*this);
    ++(*this);
    return tmp;
  }

  friend bool operator==(const specific_decl_iterator& x,
                         const specific_decl_iterator& y) {
    return x.Current == y.Current;
  }

  friend bool operator!=(const specific_decl_iterator& x,
                         const specific_decl_iterator& y) {
    return x.Current != y.Current;
  }
};

/// Iterates over a filtered subrange of declarations stored
/// in a DeclContext.
///
/// This iterator visits only those declarations that are of type
/// SpecificDecl (or a class derived from it) and that meet some
/// additional run-time criteria. This iterator is used, for
/// example, to provide access to the instance methods within an
/// Objective-C interface (with SpecificDecl = ObjCMethodDecl and
/// Acceptable = ObjCMethodDecl::isInstanceMethod).
template<typename SpecificDecl, bool (SpecificDecl::*Acceptable)() const>
class filtered_decl_iterator {
  /// Current - The current, underlying declaration iterator, which
  /// will either be NULL or will point to a declaration of
  /// type SpecificDecl.
  DeclContext::decl_iterator Current;

  /// SkipToNextDecl - Advances the current position up to the next
  /// declaration of type SpecificDecl that also meets the criteria
  /// required by Acceptable.
  void SkipToNextDecl() {
    while (*Current &&
           (!isa<SpecificDecl>(*Current) ||
            (Acceptable && !(cast<SpecificDecl>(*Current)->*Acceptable)())))
      ++Current;
  }

public:
  using value_type = SpecificDecl *;
  // TODO: Add reference and pointer types (with some appropriate proxy type)
  // if we ever have a need for them.
  using reference = void;
  using pointer = void;
  using difference_type =
      std::iterator_traits<DeclContext::decl_iterator>::difference_type;
  using iterator_category = std::forward_iterator_tag;

  filtered_decl_iterator() = default;

  /// filtered_decl_iterator - Construct a new iterator over a
  /// subset of the declarations the range [C,
  /// end-of-declarations). If A is non-NULL, it is a pointer to a
  /// member function of SpecificDecl that should return true for
  /// all of the SpecificDecl instances that will be in the subset
  /// of iterators. For example, if you want Objective-C instance
  /// methods, SpecificDecl will be ObjCMethodDecl and A will be
  /// &ObjCMethodDecl::isInstanceMethod.
  explicit filtered_decl_iterator(DeclContext::decl_iterator C) : Current(C) {
    SkipToNextDecl();
  }

  value_type operator*() const { return cast<SpecificDecl>(*Current); }
  value_type operator->() const { return cast<SpecificDecl>(*Current); }

  filtered_decl_iterator& operator++() {
    ++Current;
    SkipToNextDecl();
    return *this;
  }

  filtered_decl_iterator operator++(int) {
    filtered_decl_iterator tmp(*this);
    ++(*this);
    return tmp;
  }

  friend bool operator==(const filtered_decl_iterator& x,
                         const filtered_decl_iterator& y) {
    return x.Current == y.Current;
  }

  friend bool operator!=(const filtered_decl_iterator& x,
                         const filtered_decl_iterator& y) {
    return x.Current != y.Current;
  }
};

/// Add the declaration D into this context.
///
/// This routine should be invoked when the declaration D has first
/// been declared, to place D into the context where it was
/// (lexically) defined. Every declaration must be added to one
/// (and only one!) context, where it can be visited via
/// [decls_begin(), decls_end()). Once a declaration has been added
/// to its lexical context, the corresponding DeclContext owns the
/// declaration.
///
/// If D is also a NamedDecl, it will be made visible within its
/// semantic context via makeDeclVisibleInContext.
void addDecl(Decl *D);

/// Add the declaration D into this context, but suppress
/// searches for external declarations with the same name.
///
/// Although analogous in function to addDecl, this removes an
/// important check.  This is only useful if the Decl is being
/// added in response to an external search; in all other cases,
/// addDecl() is the right function to use.
/// See the ASTImporter for use cases.
void addDeclInternal(Decl *D);

/// Add the declaration D to this context without modifying
/// any lookup tables.
///
/// This is useful for some operations in dependent contexts where
/// the semantic context might not be dependent;  this basically
/// only happens with friends.
void addHiddenDecl(Decl *D);

/// Removes a declaration from this context.
void removeDecl(Decl *D);

/// Checks whether a declaration is in this context.
bool containsDecl(Decl *D) const;

/// Checks whether a declaration is in this context.
/// This also loads the Decls from the external source before the check.
bool containsDeclAndLoad(Decl *D) const;

using lookup_result = DeclContextLookupResult;
using lookup_iterator = lookup_result::iterator;

/// lookup - Find the declarations (if any) with the given Name in
/// this context. Returns a range of iterators that contains all of
/// the declarations with this name, with object, function, member,
/// and enumerator names preceding any tag name. Note that this
/// routine will not look into parent contexts.
lookup_result lookup(DeclarationName Name) const;

/// Find the declarations with the given name that are visible
/// within this context; don't attempt to retrieve anything from an
/// external source.
lookup_result noload_lookup(DeclarationName Name);

/// A simplistic name lookup mechanism that performs name lookup
/// into this declaration context without consulting the external source.
///
/// This function should almost never be used, because it subverts the
/// usual relationship between a DeclContext and the external source.
/// See the ASTImporter for the (few, but important) use cases.
///
/// FIXME: This is very inefficient; replace uses of it with uses of
/// noload_lookup.
void localUncachedLookup(DeclarationName Name,
                         SmallVectorImpl<NamedDecl *> &Results);

/// Makes a declaration visible within this context.
///
/// This routine makes the declaration D visible to name lookup
/// within this context and, if this is a transparent context,
/// within its parent contexts up to the first enclosing
/// non-transparent context. Making a declaration visible within a
/// context does not transfer ownership of a declaration, and a
/// declaration can be visible in many contexts that aren't its
/// lexical context.
///
/// If D is a redeclaration of an existing declaration that is
/// visible from this context, as determined by
/// NamedDecl::declarationReplaces, the previous declaration will be
/// replaced with D.
void makeDeclVisibleInContext(NamedDecl *D);

/// all_lookups_iterator - An iterator that provides a view over the results
/// of looking up every possible name.
class all_lookups_iterator;

using lookups_range = llvm::iterator_range<all_lookups_iterator>;

lookups_range lookups() const;
// Like lookups(), but avoids loading external declarations.
// If PreserveInternalState, avoids building lookup data structures too.
lookups_range noload_lookups(bool PreserveInternalState) const;

/// Iterators over all possible lookups within this context.
all_lookups_iterator lookups_begin() const;
all_lookups_iterator lookups_end() const;

/// Iterators over all possible lookups within this context that are
/// currently loaded; don't attempt to retrieve anything from an external
/// source.
all_lookups_iterator noload_lookups_begin() const;
all_lookups_iterator noload_lookups_end() const;

struct udir_iterator;

using udir_iterator_base =
    llvm::iterator_adaptor_base<udir_iterator, lookup_iterator,
                                typename lookup_iterator::iterator_category,
                                UsingDirectiveDecl *>;

struct udir_iterator : udir_iterator_base {
  udir_iterator(lookup_iterator I) : udir_iterator_base(I) {}

  UsingDirectiveDecl *operator*() const;
};

using udir_range = llvm::iterator_range<udir_iterator>;

udir_range using_directives() const;

// These are all defined in DependentDiagnostic.h.
class ddiag_iterator;

using ddiag_range = llvm::iterator_range<DeclContext::ddiag_iterator>;

inline ddiag_range ddiags() const;

// Low-level accessors

/// Mark that there are external lexical declarations that we need
/// to include in our lookup table (and that are not available as external
/// visible lookups). These extra lookup results will be found by walking
/// the lexical declarations of this context. This should be used only if
/// setHasExternalLexicalStorage() has been called on any decl context for
/// which this is the primary context.
void setMustBuildLookupTable() {
  assert(this == getPrimaryContext() &&((void)0)
         "should only be called on primary context")((void)0);
  DeclContextBits.HasLazyExternalLexicalLookups = true;
}

/// Retrieve the internal representation of the lookup structure.
/// This may omit some names if we are lazily building the structure.
StoredDeclsMap *getLookupPtr() const { return LookupPtr; }

/// Ensure the lookup structure is fully-built and return it.
StoredDeclsMap *buildLookup();

/// Whether this DeclContext has external storage containing
/// additional declarations that are lexically in this context.
bool hasExternalLexicalStorage() const {
  return DeclContextBits.ExternalLexicalStorage;
}

/// State whether this DeclContext has external storage for
/// declarations lexically in this context.
void setHasExternalLexicalStorage(bool ES = true) const {
  DeclContextBits.ExternalLexicalStorage = ES;
}

/// Whether this DeclContext has external storage containing
/// additional declarations that are visible in this context.
bool hasExternalVisibleStorage() const {
  return DeclContextBits.ExternalVisibleStorage;
}

/// State whether this DeclContext has external storage for
/// declarations visible in this context.
void setHasExternalVisibleStorage(bool ES = true) const {
  DeclContextBits.ExternalVisibleStorage = ES;
  if (ES && LookupPtr)
    DeclContextBits.NeedToReconcileExternalVisibleStorage = true;
}

/// Determine whether the given declaration is stored in the list of
/// declarations lexically within this context.
bool isDeclInLexicalTraversal(const Decl *D) const {
  return D && (D->NextInContextAndBits.getPointer() || D == FirstDecl ||
               D == LastDecl);
}

bool setUseQualifiedLookup(bool use = true) const {
  bool old_value = DeclContextBits.UseQualifiedLookup;
  DeclContextBits.UseQualifiedLookup = use;
  return old_value;
}

bool shouldUseQualifiedLookup() const {
  return DeclContextBits.UseQualifiedLookup;
}

static bool classof(const Decl *D);
static bool classof(const DeclContext *D) { return true; }

void dumpDeclContext() const;
void dumpLookups() const;
void dumpLookups(llvm::raw_ostream &OS, bool DumpDecls = false,
                 bool Deserialize = false) const;

2473private:
/// Whether this declaration context has had externally visible
/// storage added since the last lookup. In this case, \c LookupPtr's
/// invariant may not hold and needs to be fixed before we perform
/// another lookup.
bool hasNeedToReconcileExternalVisibleStorage() const {
  return DeclContextBits.NeedToReconcileExternalVisibleStorage;
}

/// State that this declaration context has had externally visible
/// storage added since the last lookup. In this case, \c LookupPtr's
/// invariant may not hold and needs to be fixed before we perform
/// another lookup.
void setNeedToReconcileExternalVisibleStorage(bool Need = true) const {
  DeclContextBits.NeedToReconcileExternalVisibleStorage = Need;
}

/// If \c true, this context may have local lexical declarations
/// that are missing from the lookup table.
bool hasLazyLocalLexicalLookups() const {
  return DeclContextBits.HasLazyLocalLexicalLookups;
}

/// If \c true, this context may have local lexical declarations
/// that are missing from the lookup table.
void setHasLazyLocalLexicalLookups(bool HasLLLL = true) const {
  DeclContextBits.HasLazyLocalLexicalLookups = HasLLLL;
}

/// If \c true, the external source may have lexical declarations
/// that are missing from the lookup table.
bool hasLazyExternalLexicalLookups() const {
  return DeclContextBits.HasLazyExternalLexicalLookups;
}

/// If \c true, the external source may have lexical declarations
/// that are missing from the lookup table.
void setHasLazyExternalLexicalLookups(bool HasLELL = true) const {
  DeclContextBits.HasLazyExternalLexicalLookups = HasLELL;
}

void reconcileExternalVisibleStorage() const;
bool LoadLexicalDeclsFromExternalStorage() const;

/// Makes a declaration visible within this context, but
/// suppresses searches for external declarations with the same
/// name.
///
/// Analogous to makeDeclVisibleInContext, but for the exclusive
/// use of addDeclInternal().
void makeDeclVisibleInContextInternal(NamedDecl *D);

StoredDeclsMap *CreateStoredDeclsMap(ASTContext &C) const;

void loadLazyLocalLexicalLookups();
void buildLookupImpl(DeclContext *DCtx, bool Internal);
void makeDeclVisibleInContextWithFlags(NamedDecl *D, bool Internal,
                                       bool Rediscoverable);
void makeDeclVisibleInContextImpl(NamedDecl *D, bool Internal);
2532};

2534inline bool Decl::isTemplateParameter() const {
return getKind() == TemplateTypeParm || getKind() == NonTypeTemplateParm ||
       getKind() == TemplateTemplateParm;
2537}

2539// Specialization selected when ToTy is not a known subclass of DeclContext.
2540template <class ToTy,
        bool IsKnownSubtype = ::std::is_base_of<DeclContext, ToTy>::value>
2542struct cast_convert_decl_context {
static const ToTy *doit(const DeclContext *Val) {
  return static_cast<const ToTy*>(Decl::castFromDeclContext(Val));
}

static ToTy *doit(DeclContext *Val) {
  return static_cast<ToTy*>(Decl::castFromDeclContext(Val));
}
2550};

2552// Specialization selected when ToTy is a known subclass of DeclContext.
2553template <class ToTy>
2554struct cast_convert_decl_context<ToTy, true> {
static const ToTy *doit(const DeclContext *Val) {
  return static_cast<const ToTy*>(Val);
}

static ToTy *doit(DeclContext *Val) {
  return static_cast<ToTy*>(Val);
}
2562};

2564} // namespace clang

2566namespace llvm {

2568/// isa<T>(DeclContext*)
2569template <typename To>
2570struct isa_impl<To, ::clang::DeclContext> {
static bool doit(const ::clang::DeclContext &Val) {
  return To::classofKind(Val.getDeclKind());
}
2574};

2576/// cast<T>(DeclContext*)
2577template<class ToTy>
2578struct cast_convert_val<ToTy,
                      const ::clang::DeclContext,const ::clang::DeclContext> {
static const ToTy &doit(const ::clang::DeclContext &Val) {
  return *::clang::cast_convert_decl_context<ToTy>::doit(&Val);
}
2583};

2585template<class ToTy>
2586struct cast_convert_val<ToTy, ::clang::DeclContext, ::clang::DeclContext> {
static ToTy &doit(::clang::DeclContext &Val) {
  return *::clang::cast_convert_decl_context<ToTy>::doit(&Val);
}
2590};

2592template<class ToTy>
2593struct cast_convert_val<ToTy,
                   const ::clang::DeclContext*, const ::clang::DeclContext*> {
static const ToTy *doit(const ::clang::DeclContext *Val) {
  return ::clang::cast_convert_decl_context<ToTy>::doit(Val);
}
2598};

2600template<class ToTy>
2601struct cast_convert_val<ToTy, ::clang::DeclContext*, ::clang::DeclContext*> {
static ToTy *doit(::clang::DeclContext *Val) {
  return ::clang::cast_convert_decl_context<ToTy>::doit(Val);
}
2605};

2607/// Implement cast_convert_val for Decl -> DeclContext conversions.
2608template<class FromTy>
2609struct cast_convert_val< ::clang::DeclContext, FromTy, FromTy> {
static ::clang::DeclContext &doit(const FromTy &Val) {
  return *FromTy::castToDeclContext(&Val);
}
2613};

2615template<class FromTy>
2616struct cast_convert_val< ::clang::DeclContext, FromTy*, FromTy*> {
static ::clang::DeclContext *doit(const FromTy *Val) {
  return FromTy::castToDeclContext(Val);
}
2620};

2622template<class FromTy>
2623struct cast_convert_val< const ::clang::DeclContext, FromTy, FromTy> {
static const ::clang::DeclContext &doit(const FromTy &Val) {
  return *FromTy::castToDeclContext(&Val);
}
2627};

2629template<class FromTy>
2630struct cast_convert_val< const ::clang::DeclContext, FromTy*, FromTy*> {
static const ::clang::DeclContext *doit(const FromTy *Val) {
  return FromTy::castToDeclContext(Val);
}
2634};

2636} // namespace llvm

2638#endif // LLVM_CLANG_AST_DECLBASE_H