/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp

Bug Summary

File:	src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp
Warning:	line 809, column 8 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 IRForTarget.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/liblldbPluginExpressionParser/obj -resource-dir /usr/local/lib/clang/13.0.0 -I /usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/llvm/include -I /usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../include -I /usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/obj -I /usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/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/liblldbPluginExpressionParser/../../../llvm/lldb/include -I /usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source -I /usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/clang/include -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/liblldbPluginExpressionParser/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/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp

/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp

→

1//===-- IRForTarget.cpp ---------------------------------------------------===//
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//===----------------------------------------------------------------------===//

9#include "IRForTarget.h"

11#include "ClangExpressionDeclMap.h"
12#include "ClangUtil.h"

14#include "Plugins/TypeSystem/Clang/TypeSystemClang.h"
15#include "llvm/IR/Constants.h"
16#include "llvm/IR/DataLayout.h"
17#include "llvm/IR/Operator.h"
18#include "llvm/IR/InstrTypes.h"
19#include "llvm/IR/Instructions.h"
20#include "llvm/IR/Intrinsics.h"
21#include "llvm/IR/LegacyPassManager.h"
22#include "llvm/IR/Metadata.h"
23#include "llvm/IR/Module.h"
24#include "llvm/IR/ValueSymbolTable.h"
25#include "llvm/Support/raw_ostream.h"
26#include "llvm/Transforms/IPO.h"

28#include "clang/AST/ASTContext.h"

30#include "lldb/Core/dwarf.h"
31#include "lldb/Expression/IRExecutionUnit.h"
32#include "lldb/Expression/IRInterpreter.h"
33#include "lldb/Symbol/CompilerType.h"
34#include "lldb/Utility/ConstString.h"
35#include "lldb/Utility/DataBufferHeap.h"
36#include "lldb/Utility/Endian.h"
37#include "lldb/Utility/Log.h"
38#include "lldb/Utility/Scalar.h"
39#include "lldb/Utility/StreamString.h"

41#include <map>

43using namespace llvm;

45typedef SmallVector<Instruction *, 2> InstrList;

47IRForTarget::FunctionValueCache::FunctionValueCache(Maker const &maker)
  : m_maker(maker), m_values() {}

50IRForTarget::FunctionValueCache::~FunctionValueCache() = default;

52llvm::Value *
53IRForTarget::FunctionValueCache::GetValue(llvm::Function *function) {
if (!m_values.count(function)) {
  llvm::Value *ret = m_maker(function);
  m_values[function] = ret;
  return ret;
}
return m_values[function];
60}

62static llvm::Value *FindEntryInstruction(llvm::Function *function) {
if (function->empty())
  return nullptr;

return function->getEntryBlock().getFirstNonPHIOrDbg();
67}

69IRForTarget::IRForTarget(lldb_private::ClangExpressionDeclMap *decl_map,
                       bool resolve_vars,
                       lldb_private::IRExecutionUnit &execution_unit,
                       lldb_private::Stream &error_stream,
                       const char *func_name)
  : m_resolve_vars(resolve_vars), m_func_name(func_name),
    m_decl_map(decl_map), m_error_stream(error_stream),
    m_execution_unit(execution_unit),
    m_entry_instruction_finder(FindEntryInstruction) {}

79/* Handy utility functions used at several places in the code */

81static std::string PrintValue(const Value *value, bool truncate = false) {
std::string s;
if (value) {
  raw_string_ostream rso(s);
  value->print(rso);
  rso.flush();
  if (truncate)
    s.resize(s.length() - 1);
}
return s;
91}

93static std::string PrintType(const llvm::Type *type, bool truncate = false) {
std::string s;
raw_string_ostream rso(s);
type->print(rso);
rso.flush();
if (truncate)
  s.resize(s.length() - 1);
return s;
101}

103bool IRForTarget::FixFunctionLinkage(llvm::Function &llvm_function) {
llvm_function.setLinkage(GlobalValue::ExternalLinkage);

return true;
107}

109clang::NamedDecl *IRForTarget::DeclForGlobal(const GlobalValue *global_val,
                                           Module *module) {
NamedMDNode *named_metadata =
    module->getNamedMetadata("clang.global.decl.ptrs");

if (!named_metadata)
  return nullptr;

unsigned num_nodes = named_metadata->getNumOperands();
unsigned node_index;

for (node_index = 0; node_index < num_nodes; ++node_index) {
  llvm::MDNode *metadata_node =
      dyn_cast<llvm::MDNode>(named_metadata->getOperand(node_index));
  if (!metadata_node)
    return nullptr;

  if (metadata_node->getNumOperands() != 2)
    continue;

  if (mdconst::dyn_extract_or_null<GlobalValue>(
          metadata_node->getOperand(0)) != global_val)
    continue;

  ConstantInt *constant_int =
      mdconst::dyn_extract<ConstantInt>(metadata_node->getOperand(1));

  if (!constant_int)
    return nullptr;

  uintptr_t ptr = constant_int->getZExtValue();

  return reinterpret_cast<clang::NamedDecl *>(ptr);
}

return nullptr;
145}

147clang::NamedDecl *IRForTarget::DeclForGlobal(GlobalValue *global_val) {
return DeclForGlobal(global_val, m_module);
149}

151/// Returns true iff the mangled symbol is for a static guard variable.
152static bool isGuardVariableSymbol(llvm::StringRef mangled_symbol,
                                bool check_ms_abi = true) {
bool result = mangled_symbol.startswith("_ZGV"); // Itanium ABI guard variable
if (check_ms_abi)
  result |= mangled_symbol.endswith("@4IA"); // Microsoft ABI
return result;
158}

160bool IRForTarget::CreateResultVariable(llvm::Function &llvm_function) {
lldb_private::Log *log(
    lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS(1u << 8)));

if (!m_resolve_vars)
  return true;

// Find the result variable.  If it doesn't exist, we can give up right here.

ValueSymbolTable &value_symbol_table = m_module->getValueSymbolTable();

llvm::StringRef result_name;
bool found_result = false;

for (StringMapEntry<llvm::Value *> &value_symbol : value_symbol_table) {
  result_name = value_symbol.first();

  // Check if this is a guard variable. It seems this causes some hiccups
  // on Windows, so let's only check for Itanium guard variables.
  bool is_guard_var = isGuardVariableSymbol(result_name, /*MS ABI*/ false);

  if (result_name.contains("$__lldb_expr_result_ptr") && !is_guard_var) {
    found_result = true;
    m_result_is_pointer = true;
    break;
  }

  if (result_name.contains("$__lldb_expr_result") && !is_guard_var) {
    found_result = true;
    m_result_is_pointer = false;
    break;
  }
}

if (!found_result) {
  LLDB_LOG(log, "Couldn't find result variable")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Couldn't find result variable"); } while (0);

  return true;
}

LLDB_LOG(log, "Result name: \"{0}\"", result_name)do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Result name: \"{0}\"", result_name); } while (0);

Value *result_value = m_module->getNamedValue(result_name);

if (!result_value) {
  LLDB_LOG(log, "Result variable had no data")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Result variable had no data"); } while (0);

  m_error_stream.Format("Internal error [IRForTarget]: Result variable's "
                        "name ({0}) exists, but not its definition\n",
                        result_name);

  return false;
}

LLDB_LOG(log, "Found result in the IR: \"{0}\"",do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Found result in the IR: \"{0}\"", PrintValue(result_value
, false)); } while (0)
         PrintValue(result_value, false))do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Found result in the IR: \"{0}\"", PrintValue(result_value
, false)); } while (0);

GlobalVariable *result_global = dyn_cast<GlobalVariable>(result_value);

if (!result_global) {
  LLDB_LOG(log, "Result variable isn't a GlobalVariable")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Result variable isn't a GlobalVariable"); } while
 (0);

  m_error_stream.Format("Internal error [IRForTarget]: Result variable ({0}) "
                        "is defined, but is not a global variable\n",
                        result_name);

  return false;
}

clang::NamedDecl *result_decl = DeclForGlobal(result_global);
if (!result_decl) {
  LLDB_LOG(log, "Result variable doesn't have a corresponding Decl")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Result variable doesn't have a corresponding Decl"
); } while (0);

  m_error_stream.Format("Internal error [IRForTarget]: Result variable ({0}) "
                        "does not have a corresponding Clang entity\n",
                        result_name);

  return false;
}

if (log) {
  std::string decl_desc_str;
  raw_string_ostream decl_desc_stream(decl_desc_str);
  result_decl->print(decl_desc_stream);
  decl_desc_stream.flush();

  LLDB_LOG(log, "Found result decl: \"{0}\"", decl_desc_str)do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Found result decl: \"{0}\"", decl_desc_str); } while
 (0);
}

clang::VarDecl *result_var = dyn_cast<clang::VarDecl>(result_decl);
if (!result_var) {
  LLDB_LOG(log, "Result variable Decl isn't a VarDecl")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Result variable Decl isn't a VarDecl"); } while (
0);

  m_error_stream.Format("Internal error [IRForTarget]: Result variable "
                        "({0})'s corresponding Clang entity isn't a "
                        "variable\n",
                        result_name);

  return false;
}

// Get the next available result name from m_decl_map and create the
// persistent variable for it

// If the result is an Lvalue, it is emitted as a pointer; see
// ASTResultSynthesizer::SynthesizeBodyResult.
if (m_result_is_pointer) {
  clang::QualType pointer_qual_type = result_var->getType();
  const clang::Type *pointer_type = pointer_qual_type.getTypePtr();

  const clang::PointerType *pointer_pointertype =
      pointer_type->getAs<clang::PointerType>();
  const clang::ObjCObjectPointerType *pointer_objcobjpointertype =
      pointer_type->getAs<clang::ObjCObjectPointerType>();

  if (pointer_pointertype) {
    clang::QualType element_qual_type = pointer_pointertype->getPointeeType();

    m_result_type = lldb_private::TypeFromParser(
        m_decl_map->GetTypeSystem()->GetType(element_qual_type));
  } else if (pointer_objcobjpointertype) {
    clang::QualType element_qual_type =
        clang::QualType(pointer_objcobjpointertype->getObjectType(), 0);

    m_result_type = lldb_private::TypeFromParser(
        m_decl_map->GetTypeSystem()->GetType(element_qual_type));
  } else {
    LLDB_LOG(log, "Expected result to have pointer type, but it did not")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Expected result to have pointer type, but it did not"
); } while (0);

    m_error_stream.Format("Internal error [IRForTarget]: Lvalue result ({0}) "
                          "is not a pointer variable\n",
                          result_name);

    return false;
  }
} else {
  m_result_type = lldb_private::TypeFromParser(
      m_decl_map->GetTypeSystem()->GetType(result_var->getType()));
}

lldb::TargetSP target_sp(m_execution_unit.GetTarget());
llvm::Optional<uint64_t> bit_size = m_result_type.GetBitSize(target_sp.get());
if (!bit_size) {
  lldb_private::StreamString type_desc_stream;
  m_result_type.DumpTypeDescription(&type_desc_stream);

  LLDB_LOG(log, "Result type has unknown size")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Result type has unknown size"); } while (0);

  m_error_stream.Printf("Error [IRForTarget]: Size of result type '%s' "
                        "couldn't be determined\n",
                        type_desc_stream.GetData());
  return false;
}

if (log) {
  lldb_private::StreamString type_desc_stream;
  m_result_type.DumpTypeDescription(&type_desc_stream);

  LLDB_LOG(log, "Result decl type: \"{0}\"", type_desc_stream.GetData())do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Result decl type: \"{0}\"", type_desc_stream.GetData
()); } while (0);
}

m_result_name = lldb_private::ConstString("$RESULT_NAME");

LLDB_LOG(log, "Creating a new result global: \"{0}\" with size {1}",do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Creating a new result global: \"{0}\" with size {1}"
, m_result_name, m_result_type.GetByteSize(target_sp.get()).getValueOr
(0)); } while (0)
         m_result_name,do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Creating a new result global: \"{0}\" with size {1}"
, m_result_name, m_result_type.GetByteSize(target_sp.get()).getValueOr
(0)); } while (0)
         m_result_type.GetByteSize(target_sp.get()).getValueOr(0))do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Creating a new result global: \"{0}\" with size {1}"
, m_result_name, m_result_type.GetByteSize(target_sp.get()).getValueOr
(0)); } while (0);

// Construct a new result global and set up its metadata

GlobalVariable *new_result_global = new GlobalVariable(
    (*m_module), result_global->getType()->getElementType(),
    false,                                 /* not constant */
    GlobalValue::ExternalLinkage, nullptr, /* no initializer */
    m_result_name.GetCString());

// It's too late in compilation to create a new VarDecl for this, but we
// don't need to.  We point the metadata at the old VarDecl.  This creates an
// odd anomaly: a variable with a Value whose name is something like $0 and a
// Decl whose name is $__lldb_expr_result.  This condition is handled in
// ClangExpressionDeclMap::DoMaterialize, and the name of the variable is
// fixed up.

ConstantInt *new_constant_int =
    ConstantInt::get(llvm::Type::getInt64Ty(m_module->getContext()),
                     reinterpret_cast<uintptr_t>(result_decl), false);

llvm::Metadata *values[2];
values[0] = ConstantAsMetadata::get(new_result_global);
values[1] = ConstantAsMetadata::get(new_constant_int);

ArrayRef<Metadata *> value_ref(values, 2);

MDNode *persistent_global_md = MDNode::get(m_module->getContext(), value_ref);
NamedMDNode *named_metadata =
    m_module->getNamedMetadata("clang.global.decl.ptrs");
named_metadata->addOperand(persistent_global_md);

LLDB_LOG(log, "Replacing \"{0}\" with \"{1}\"", PrintValue(result_global),do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Replacing \"{0}\" with \"{1}\"", PrintValue(result_global
), PrintValue(new_result_global)); } while (0)
         PrintValue(new_result_global))do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Replacing \"{0}\" with \"{1}\"", PrintValue(result_global
), PrintValue(new_result_global)); } while (0);

if (result_global->use_empty()) {
  // We need to synthesize a store for this variable, because otherwise
  // there's nothing to put into its equivalent persistent variable.

  BasicBlock &entry_block(llvm_function.getEntryBlock());
  Instruction *first_entry_instruction(entry_block.getFirstNonPHIOrDbg());

  if (!first_entry_instruction)
    return false;

  if (!result_global->hasInitializer()) {
    LLDB_LOG(log, "Couldn't find initializer for unused variable")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Couldn't find initializer for unused variable");
 } while (0);

    m_error_stream.Format("Internal error [IRForTarget]: Result variable "
                          "({0}) has no writes and no initializer\n",
                          result_name);

    return false;
  }

  Constant *initializer = result_global->getInitializer();

  StoreInst *synthesized_store =
      new StoreInst(initializer, new_result_global, first_entry_instruction);

  LLDB_LOG(log, "Synthesized result store \"{0}\"\n",do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Synthesized result store \"{0}\"\n", PrintValue(
synthesized_store)); } while (0)
           PrintValue(synthesized_store))do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Synthesized result store \"{0}\"\n", PrintValue(
synthesized_store)); } while (0);
} else {
  result_global->replaceAllUsesWith(new_result_global);
}

if (!m_decl_map->AddPersistentVariable(
        result_decl, m_result_name, m_result_type, true, m_result_is_pointer))
  return false;

result_global->eraseFromParent();

return true;
398}

400bool IRForTarget::RewriteObjCConstString(llvm::GlobalVariable *ns_str,
                                       llvm::GlobalVariable *cstr) {
lldb_private::Log *log(
    lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS(1u << 8)));

Type *ns_str_ty = ns_str->getType();

Type *i8_ptr_ty = Type::getInt8PtrTy(m_module->getContext());
Type *i32_ty = Type::getInt32Ty(m_module->getContext());
Type *i8_ty = Type::getInt8Ty(m_module->getContext());

if (!m_CFStringCreateWithBytes) {
  lldb::addr_t CFStringCreateWithBytes_addr;

  static lldb_private::ConstString g_CFStringCreateWithBytes_str(
      "CFStringCreateWithBytes");

  bool missing_weak = false;
  CFStringCreateWithBytes_addr =
      m_execution_unit.FindSymbol(g_CFStringCreateWithBytes_str, 
                                  missing_weak);
  if (CFStringCreateWithBytes_addr == LLDB_INVALID_ADDRESS0xffffffffffffffffULL || missing_weak) {
    LLDB_LOG(log, "Couldn't find CFStringCreateWithBytes in the target")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Couldn't find CFStringCreateWithBytes in the target"
); } while (0);

    m_error_stream.Printf("Error [IRForTarget]: Rewriting an Objective-C "
                          "constant string requires "
                          "CFStringCreateWithBytes\n");

    return false;
  }

  LLDB_LOG(log, "Found CFStringCreateWithBytes at {0}",do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Found CFStringCreateWithBytes at {0}", CFStringCreateWithBytes_addr
); } while (0)
           CFStringCreateWithBytes_addr)do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Found CFStringCreateWithBytes at {0}", CFStringCreateWithBytes_addr
); } while (0);

  // Build the function type:
  //
  // CFStringRef CFStringCreateWithBytes (
  //   CFAllocatorRef alloc,
  //   const UInt8 *bytes,
  //   CFIndex numBytes,
  //   CFStringEncoding encoding,
  //   Boolean isExternalRepresentation
  // );
  //
  // We make the following substitutions:
  //
  // CFStringRef -> i8*
  // CFAllocatorRef -> i8*
  // UInt8 * -> i8*
  // CFIndex -> long (i32 or i64, as appropriate; we ask the module for its
  // pointer size for now) CFStringEncoding -> i32 Boolean -> i8

  Type *arg_type_array[5];

  arg_type_array[0] = i8_ptr_ty;
  arg_type_array[1] = i8_ptr_ty;
  arg_type_array[2] = m_intptr_ty;
  arg_type_array[3] = i32_ty;
  arg_type_array[4] = i8_ty;

  ArrayRef<Type *> CFSCWB_arg_types(arg_type_array, 5);

  llvm::FunctionType *CFSCWB_ty =
      FunctionType::get(ns_str_ty, CFSCWB_arg_types, false);

  // Build the constant containing the pointer to the function
  PointerType *CFSCWB_ptr_ty = PointerType::getUnqual(CFSCWB_ty);
  Constant *CFSCWB_addr_int =
      ConstantInt::get(m_intptr_ty, CFStringCreateWithBytes_addr, false);
  m_CFStringCreateWithBytes = {
      CFSCWB_ty, ConstantExpr::getIntToPtr(CFSCWB_addr_int, CFSCWB_ptr_ty)};
}

ConstantDataSequential *string_array = nullptr;

if (cstr)
  string_array = dyn_cast<ConstantDataSequential>(cstr->getInitializer());

Constant *alloc_arg = Constant::getNullValue(i8_ptr_ty);
Constant *bytes_arg = cstr ? ConstantExpr::getBitCast(cstr, i8_ptr_ty)
                           : Constant::getNullValue(i8_ptr_ty);
Constant *numBytes_arg = ConstantInt::get(
    m_intptr_ty, cstr ? (string_array->getNumElements() - 1) * string_array->getElementByteSize() : 0, false);
int encoding_flags = 0;
switch (cstr ? string_array->getElementByteSize() : 1) {
case 1:
 encoding_flags = 0x08000100; /* 0x08000100 is kCFStringEncodingUTF8 */
 break;
case 2:
 encoding_flags = 0x0100; /* 0x0100 is kCFStringEncodingUTF16 */
 break;
case 4:
 encoding_flags = 0x0c000100; /* 0x0c000100 is kCFStringEncodingUTF32 */
 break;
default:
 encoding_flags = 0x0600; /* fall back to 0x0600, kCFStringEncodingASCII */
 LLDB_LOG(log, "Encountered an Objective-C constant string with unusual "do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Encountered an Objective-C constant string with unusual "
 "element size {0}", string_array->getElementByteSize()); }
 while (0)
               "element size {0}",do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Encountered an Objective-C constant string with unusual "
 "element size {0}", string_array->getElementByteSize()); }
 while (0)
          string_array->getElementByteSize())do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Encountered an Objective-C constant string with unusual "
 "element size {0}", string_array->getElementByteSize()); }
 while (0);
}
Constant *encoding_arg = ConstantInt::get(i32_ty, encoding_flags, false);
Constant *isExternal_arg =
   ConstantInt::get(i8_ty, 0x0, false); /* 0x0 is false */

Value *argument_array[5];

argument_array[0] = alloc_arg;
argument_array[1] = bytes_arg;
argument_array[2] = numBytes_arg;
argument_array[3] = encoding_arg;
argument_array[4] = isExternal_arg;

ArrayRef<Value *> CFSCWB_arguments(argument_array, 5);

FunctionValueCache CFSCWB_Caller(
   [this, &CFSCWB_arguments](llvm::Function *function) -> llvm::Value * {
     return CallInst::Create(
         m_CFStringCreateWithBytes, CFSCWB_arguments,
         "CFStringCreateWithBytes",
         llvm::cast<Instruction>(
             m_entry_instruction_finder.GetValue(function)));
   });

if (!UnfoldConstant(ns_str, nullptr, CFSCWB_Caller, m_entry_instruction_finder,
                   m_error_stream)) {
 LLDB_LOG(log, "Couldn't replace the NSString with the result of the call")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Couldn't replace the NSString with the result of the call"
); } while (0);

 m_error_stream.Printf("error [IRForTarget internal]: Couldn't replace an "
                       "Objective-C constant string with a dynamic "
                       "string\n");

 return false;
}

ns_str->eraseFromParent();

return true;
537}

539bool IRForTarget::RewriteObjCConstStrings() {
lldb_private::Log *log(
    lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS(1u << 8)));

ValueSymbolTable &value_symbol_table = m_module->getValueSymbolTable();

for (StringMapEntry<llvm::Value *> &value_symbol : value_symbol_table) {
  llvm::StringRef value_name = value_symbol.first();

  if (value_name.contains("_unnamed_cfstring_")) {
    Value *nsstring_value = value_symbol.second;

    GlobalVariable *nsstring_global =
        dyn_cast<GlobalVariable>(nsstring_value);

    if (!nsstring_global) {
      LLDB_LOG(log, "NSString variable is not a GlobalVariable")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "NSString variable is not a GlobalVariable"); } while
 (0);

      m_error_stream.Printf("Internal error [IRForTarget]: An Objective-C "
                            "constant string is not a global variable\n");

      return false;
    }

    if (!nsstring_global->hasInitializer()) {
      LLDB_LOG(log, "NSString variable does not have an initializer")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "NSString variable does not have an initializer")
; } while (0);

      m_error_stream.Printf("Internal error [IRForTarget]: An Objective-C "
                            "constant string does not have an initializer\n");

      return false;
    }

    ConstantStruct *nsstring_struct =
        dyn_cast<ConstantStruct>(nsstring_global->getInitializer());

    if (!nsstring_struct) {
      LLDB_LOG(log,do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "NSString variable's initializer is not a ConstantStruct"
); } while (0)
               "NSString variable's initializer is not a ConstantStruct")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "NSString variable's initializer is not a ConstantStruct"
); } while (0);

      m_error_stream.Printf("Internal error [IRForTarget]: An Objective-C "
                            "constant string is not a structure constant\n");

      return false;
    }

    // We expect the following structure:
    //
    // struct {
    //   int *isa;
    //   int flags;
    //   char *str;
    //   long length;
    // };

    if (nsstring_struct->getNumOperands() != 4) {

      LLDB_LOG(log,do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "NSString variable's initializer structure has an "
 "unexpected number of members.  Should be 4, is {0}", nsstring_struct
->getNumOperands()); } while (0)
               "NSString variable's initializer structure has an "do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "NSString variable's initializer structure has an "
 "unexpected number of members.  Should be 4, is {0}", nsstring_struct
->getNumOperands()); } while (0)
               "unexpected number of members.  Should be 4, is {0}",do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "NSString variable's initializer structure has an "
 "unexpected number of members.  Should be 4, is {0}", nsstring_struct
->getNumOperands()); } while (0)
               nsstring_struct->getNumOperands())do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "NSString variable's initializer structure has an "
 "unexpected number of members.  Should be 4, is {0}", nsstring_struct
->getNumOperands()); } while (0);

      m_error_stream.Printf("Internal error [IRForTarget]: The struct for an "
                            "Objective-C constant string is not as "
                            "expected\n");

      return false;
    }

    Constant *nsstring_member = nsstring_struct->getOperand(2);

    if (!nsstring_member) {
      LLDB_LOG(log, "NSString initializer's str element was empty")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "NSString initializer's str element was empty"); }
 while (0);

      m_error_stream.Printf("Internal error [IRForTarget]: An Objective-C "
                            "constant string does not have a string "
                            "initializer\n");

      return false;
    }

    ConstantExpr *nsstring_expr = dyn_cast<ConstantExpr>(nsstring_member);

    if (!nsstring_expr) {
      LLDB_LOG(log,do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "NSString initializer's str element is not a ConstantExpr"
); } while (0)
               "NSString initializer's str element is not a ConstantExpr")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "NSString initializer's str element is not a ConstantExpr"
); } while (0);

      m_error_stream.Printf("Internal error [IRForTarget]: An Objective-C "
                            "constant string's string initializer is not "
                            "constant\n");

      return false;
    }

    GlobalVariable *cstr_global = nullptr;

    if (nsstring_expr->getOpcode() == Instruction::GetElementPtr) {
      Constant *nsstring_cstr = nsstring_expr->getOperand(0);
      cstr_global = dyn_cast<GlobalVariable>(nsstring_cstr);
    } else if (nsstring_expr->getOpcode() == Instruction::BitCast) {
      Constant *nsstring_cstr = nsstring_expr->getOperand(0);
      cstr_global = dyn_cast<GlobalVariable>(nsstring_cstr);
    }

    if (!cstr_global) {
      LLDB_LOG(log,do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "NSString initializer's str element is not a GlobalVariable"
); } while (0)
               "NSString initializer's str element is not a GlobalVariable")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "NSString initializer's str element is not a GlobalVariable"
); } while (0);

      m_error_stream.Printf("Internal error [IRForTarget]: Unhandled"
                            "constant string initializer\n");

      return false;
    }

    if (!cstr_global->hasInitializer()) {
      LLDB_LOG(log, "NSString initializer's str element does not have an "do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "NSString initializer's str element does not have an "
 "initializer"); } while (0)
                    "initializer")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "NSString initializer's str element does not have an "
 "initializer"); } while (0);

      m_error_stream.Printf("Internal error [IRForTarget]: An Objective-C "
                            "constant string's string initializer doesn't "
                            "point to initialized data\n");

      return false;
    }

    /*
    if (!cstr_array)
    {
        if (log)
            log->PutCString("NSString initializer's str element is not a
    ConstantArray");

        if (m_error_stream)
            m_error_stream.Printf("Internal error [IRForTarget]: An
    Objective-C constant string's string initializer doesn't point to an
    array\n");

        return false;
    }

    if (!cstr_array->isCString())
    {
        if (log)
            log->PutCString("NSString initializer's str element is not a C
    string array");

        if (m_error_stream)
            m_error_stream.Printf("Internal error [IRForTarget]: An
    Objective-C constant string's string initializer doesn't point to a C
    string\n");

        return false;
    }
    */

    ConstantDataArray *cstr_array =
        dyn_cast<ConstantDataArray>(cstr_global->getInitializer());

    if (cstr_array)
      LLDB_LOG(log, "Found NSString constant {0}, which contains \"{1}\"",do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Found NSString constant {0}, which contains \"{1}\""
, value_name, cstr_array->getAsString()); } while (0)
               value_name, cstr_array->getAsString())do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Found NSString constant {0}, which contains \"{1}\""
, value_name, cstr_array->getAsString()); } while (0);
    else
      LLDB_LOG(log, "Found NSString constant {0}, which contains \"\"",do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Found NSString constant {0}, which contains \"\""
, value_name); } while (0)
               value_name)do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Found NSString constant {0}, which contains \"\""
, value_name); } while (0);

    if (!cstr_array)
      cstr_global = nullptr;

    if (!RewriteObjCConstString(nsstring_global, cstr_global)) {
      LLDB_LOG(log, "Error rewriting the constant string")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Error rewriting the constant string"); } while (
0);

      // We don't print an error message here because RewriteObjCConstString
      // has done so for us.

      return false;
    }
  }
}

for (StringMapEntry<llvm::Value *> &value_symbol : value_symbol_table) {
  llvm::StringRef value_name = value_symbol.first();

  if (value_name == "__CFConstantStringClassReference") {
    GlobalVariable *gv = dyn_cast<GlobalVariable>(value_symbol.second);

    if (!gv) {
      LLDB_LOG(log,do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "__CFConstantStringClassReference is not a global variable"
); } while (0)
               "__CFConstantStringClassReference is not a global variable")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "__CFConstantStringClassReference is not a global variable"
); } while (0);

      m_error_stream.Printf("Internal error [IRForTarget]: Found a "
                            "CFConstantStringClassReference, but it is not a "
                            "global object\n");

      return false;
    }

    gv->eraseFromParent();

    break;
  }
}

return true;
742}

744static bool IsObjCSelectorRef(Value *value) {
GlobalVariable *global_variable = dyn_cast<GlobalVariable>(value);

return !(!global_variable || !global_variable->hasName() ||
         !global_variable->getName().startswith("OBJC_SELECTOR_REFERENCES_"));
749}

751// This function does not report errors; its callers are responsible.
752bool IRForTarget::RewriteObjCSelector(Instruction *selector_load) {
lldb_private::Log *log(
    lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS(1u << 8)));

LoadInst *load = dyn_cast<LoadInst>(selector_load);
15
←
Assuming 'selector_load' is a 'LoadInst'→

if (!load15.1
'load' is non-null
1
'load' is non-null
)
16
←
Taking false branch→
  return false;

// Unpack the message name from the selector.  In LLVM IR, an objc_msgSend
// gets represented as
//
// %tmp     = load i8** @"OBJC_SELECTOR_REFERENCES_" ; <i8*> %call    = call
// i8* (i8*, i8*, ...)* @objc_msgSend(i8* %obj, i8* %tmp, ...) ; <i8*>
//
// where %obj is the object pointer and %tmp is the selector.
//
// @"OBJC_SELECTOR_REFERENCES_" is a pointer to a character array called
// @"\01L_OBJC_llvm_moduleETH_VAR_NAllvm_moduleE_".
// @"\01L_OBJC_llvm_moduleETH_VAR_NAllvm_moduleE_" contains the string.

// Find the pointer's initializer (a ConstantExpr with opcode GetElementPtr)
// and get the string from its target

GlobalVariable *_objc_selector_references_ =
    dyn_cast<GlobalVariable>(load->getPointerOperand());
17
←
Assuming the object is a 'GlobalVariable'→

if (!_objc_selector_references_17.1
'_objc_selector_references_' is non-null
1
'_objc_selector_references_' is non-null
 ||
22
←
Taking false branch→
    !_objc_selector_references_->hasInitializer())
18
←
Calling 'GlobalVariable::hasInitializer'→
21
←
Returning from 'GlobalVariable::hasInitializer'→
  return false;

Constant *osr_initializer = _objc_selector_references_->getInitializer();

ConstantExpr *osr_initializer_expr = dyn_cast<ConstantExpr>(osr_initializer);
23
←
Assuming 'osr_initializer' is a 'ConstantExpr'→

if (!osr_initializer_expr23.1
'osr_initializer_expr' is non-null
1
'osr_initializer_expr' is non-null
 ||
25
←
Taking false branch→
    osr_initializer_expr->getOpcode() != Instruction::GetElementPtr)
24
←
Assuming the condition is false→
  return false;

Value *osr_initializer_base = osr_initializer_expr->getOperand(0);

if (!osr_initializer_base25.1
'osr_initializer_base' is non-null
1
'osr_initializer_base' is non-null
)
26
←
Taking false branch→
  return false;

// Find the string's initializer (a ConstantArray) and get the string from it

GlobalVariable *_objc_meth_var_name_ =
    dyn_cast<GlobalVariable>(osr_initializer_base);
27
←
Assuming 'osr_initializer_base' is a 'GlobalVariable'→

if (!_objc_meth_var_name_27.1
'_objc_meth_var_name_' is non-null
1
'_objc_meth_var_name_' is non-null
 || !_objc_meth_var_name_->hasInitializer())
28
←
Calling 'GlobalVariable::hasInitializer'→
31
←
Returning from 'GlobalVariable::hasInitializer'→
32
←
Taking false branch→
  return false;

Constant *omvn_initializer = _objc_meth_var_name_->getInitializer();

ConstantDataArray *omvn_initializer_array =
34
←
'omvn_initializer_array' initialized to a null pointer value→
    dyn_cast<ConstantDataArray>(omvn_initializer);
33
←
Assuming 'omvn_initializer' is not a 'ConstantDataArray'→

if (!omvn_initializer_array->isString())
35
←
Called C++ object pointer is null
  return false;

std::string omvn_initializer_string =
    std::string(omvn_initializer_array->getAsString());

LLDB_LOG(log, "Found Objective-C selector reference \"{0}\"",do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Found Objective-C selector reference \"{0}\"", omvn_initializer_string
); } while (0)
         omvn_initializer_string)do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Found Objective-C selector reference \"{0}\"", omvn_initializer_string
); } while (0);

// Construct a call to sel_registerName

if (!m_sel_registerName) {
  lldb::addr_t sel_registerName_addr;

  bool missing_weak = false;
  static lldb_private::ConstString g_sel_registerName_str("sel_registerName");
  sel_registerName_addr = m_execution_unit.FindSymbol(g_sel_registerName_str,
                                                      missing_weak);
  if (sel_registerName_addr == LLDB_INVALID_ADDRESS0xffffffffffffffffULL || missing_weak)
    return false;

  LLDB_LOG(log, "Found sel_registerName at {0}", sel_registerName_addr)do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Found sel_registerName at {0}", sel_registerName_addr
); } while (0);

  // Build the function type: struct objc_selector
  // *sel_registerName(uint8_t*)

  // The below code would be "more correct," but in actuality what's required
  // is uint8_t*
  // Type *sel_type = StructType::get(m_module->getContext());
  // Type *sel_ptr_type = PointerType::getUnqual(sel_type);
  Type *sel_ptr_type = Type::getInt8PtrTy(m_module->getContext());

  Type *type_array[1];

  type_array[0] = llvm::Type::getInt8PtrTy(m_module->getContext());

  ArrayRef<Type *> srN_arg_types(type_array, 1);

  llvm::FunctionType *srN_type =
      FunctionType::get(sel_ptr_type, srN_arg_types, false);

  // Build the constant containing the pointer to the function
  PointerType *srN_ptr_ty = PointerType::getUnqual(srN_type);
  Constant *srN_addr_int =
      ConstantInt::get(m_intptr_ty, sel_registerName_addr, false);
  m_sel_registerName = {srN_type,
                        ConstantExpr::getIntToPtr(srN_addr_int, srN_ptr_ty)};
}

Value *argument_array[1];

Constant *omvn_pointer = ConstantExpr::getBitCast(
    _objc_meth_var_name_, Type::getInt8PtrTy(m_module->getContext()));

argument_array[0] = omvn_pointer;

ArrayRef<Value *> srN_arguments(argument_array, 1);

CallInst *srN_call = CallInst::Create(m_sel_registerName, srN_arguments,
                                      "sel_registerName", selector_load);

// Replace the load with the call in all users

selector_load->replaceAllUsesWith(srN_call);

selector_load->eraseFromParent();

return true;
877}

879bool IRForTarget::RewriteObjCSelectors(BasicBlock &basic_block) {
lldb_private::Log *log(
    lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS(1u << 8)));

InstrList selector_loads;

for (Instruction &inst : basic_block) {
  if (LoadInst *load = dyn_cast<LoadInst>(&inst))
    if (IsObjCSelectorRef(load->getPointerOperand()))
      selector_loads.push_back(&inst);
}

for (Instruction *inst : selector_loads) {
13
←
Assuming '__begin1' is not equal to '__end1'→
  if (!RewriteObjCSelector(inst)) {
14
←
Calling 'IRForTarget::RewriteObjCSelector'→
    m_error_stream.Printf("Internal error [IRForTarget]: Couldn't change a "
                          "static reference to an Objective-C selector to a "
                          "dynamic reference\n");

    LLDB_LOG(log, "Couldn't rewrite a reference to an Objective-C selector")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Couldn't rewrite a reference to an Objective-C selector"
); } while (0);

    return false;
  }
}

return true;
904}

906static bool IsObjCClassReference(Value *value) {
GlobalVariable *global_variable = dyn_cast<GlobalVariable>(value);

return !(!global_variable || !global_variable->hasName() ||
         !global_variable->getName().startswith("OBJC_CLASS_REFERENCES_"));
911}

913// This function does not report errors; its callers are responsible.
914bool IRForTarget::RewriteObjCClassReference(Instruction *class_load) {
lldb_private::Log *log(
    lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS(1u << 8)));

LoadInst *load = dyn_cast<LoadInst>(class_load);

if (!load)
  return false;

// Unpack the class name from the reference.  In LLVM IR, a reference to an
// Objective-C class gets represented as
//
// %tmp     = load %struct._objc_class*,
//            %struct._objc_class** @OBJC_CLASS_REFERENCES_, align 4
//
// @"OBJC_CLASS_REFERENCES_ is a bitcast of a character array called
// @OBJC_CLASS_NAME_. @OBJC_CLASS_NAME contains the string.

// Find the pointer's initializer (a ConstantExpr with opcode BitCast) and
// get the string from its target

GlobalVariable *_objc_class_references_ =
    dyn_cast<GlobalVariable>(load->getPointerOperand());

if (!_objc_class_references_ ||
    !_objc_class_references_->hasInitializer())
  return false;

Constant *ocr_initializer = _objc_class_references_->getInitializer();

ConstantExpr *ocr_initializer_expr = dyn_cast<ConstantExpr>(ocr_initializer);

if (!ocr_initializer_expr ||
    ocr_initializer_expr->getOpcode() != Instruction::BitCast)
  return false;

Value *ocr_initializer_base = ocr_initializer_expr->getOperand(0);

if (!ocr_initializer_base)
  return false;

// Find the string's initializer (a ConstantArray) and get the string from it

GlobalVariable *_objc_class_name_ =
    dyn_cast<GlobalVariable>(ocr_initializer_base);

if (!_objc_class_name_ || !_objc_class_name_->hasInitializer())
  return false;

Constant *ocn_initializer = _objc_class_name_->getInitializer();

ConstantDataArray *ocn_initializer_array =
    dyn_cast<ConstantDataArray>(ocn_initializer);

if (!ocn_initializer_array->isString())
  return false;

std::string ocn_initializer_string =
    std::string(ocn_initializer_array->getAsString());

LLDB_LOG(log, "Found Objective-C class reference \"{0}\"",do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Found Objective-C class reference \"{0}\"", ocn_initializer_string
); } while (0)
         ocn_initializer_string)do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Found Objective-C class reference \"{0}\"", ocn_initializer_string
); } while (0);

// Construct a call to objc_getClass

if (!m_objc_getClass) {
  lldb::addr_t objc_getClass_addr;

  bool missing_weak = false;
  static lldb_private::ConstString g_objc_getClass_str("objc_getClass");
  objc_getClass_addr = m_execution_unit.FindSymbol(g_objc_getClass_str,
                                                   missing_weak);
  if (objc_getClass_addr == LLDB_INVALID_ADDRESS0xffffffffffffffffULL || missing_weak)
    return false;

  LLDB_LOG(log, "Found objc_getClass at {0}", objc_getClass_addr)do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Found objc_getClass at {0}", objc_getClass_addr)
; } while (0);

  // Build the function type: %struct._objc_class *objc_getClass(i8*)

  Type *class_type = load->getType();
  Type *type_array[1];
  type_array[0] = llvm::Type::getInt8PtrTy(m_module->getContext());

  ArrayRef<Type *> ogC_arg_types(type_array, 1);

  llvm::FunctionType *ogC_type =
      FunctionType::get(class_type, ogC_arg_types, false);

  // Build the constant containing the pointer to the function
  PointerType *ogC_ptr_ty = PointerType::getUnqual(ogC_type);
  Constant *ogC_addr_int =
      ConstantInt::get(m_intptr_ty, objc_getClass_addr, false);
  m_objc_getClass = {ogC_type,
                     ConstantExpr::getIntToPtr(ogC_addr_int, ogC_ptr_ty)};
}

Value *argument_array[1];

Constant *ocn_pointer = ConstantExpr::getBitCast(
    _objc_class_name_, Type::getInt8PtrTy(m_module->getContext()));

argument_array[0] = ocn_pointer;

ArrayRef<Value *> ogC_arguments(argument_array, 1);

CallInst *ogC_call = CallInst::Create(m_objc_getClass, ogC_arguments,
                                      "objc_getClass", class_load);

// Replace the load with the call in all users

class_load->replaceAllUsesWith(ogC_call);

class_load->eraseFromParent();

return true;
1029}

1031bool IRForTarget::RewriteObjCClassReferences(BasicBlock &basic_block) {
lldb_private::Log *log(
    lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS(1u << 8)));

InstrList class_loads;

for (Instruction &inst : basic_block) {
  if (LoadInst *load = dyn_cast<LoadInst>(&inst))
    if (IsObjCClassReference(load->getPointerOperand()))
      class_loads.push_back(&inst);
}

for (Instruction *inst : class_loads) {
  if (!RewriteObjCClassReference(inst)) {
    m_error_stream.Printf("Internal error [IRForTarget]: Couldn't change a "
                          "static reference to an Objective-C class to a "
                          "dynamic reference\n");

    LLDB_LOG(log, "Couldn't rewrite a reference to an Objective-C class")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Couldn't rewrite a reference to an Objective-C class"
); } while (0);

    return false;
  }
}

return true;
1056}

1058// This function does not report errors; its callers are responsible.
1059bool IRForTarget::RewritePersistentAlloc(llvm::Instruction *persistent_alloc) {
lldb_private::Log *log(
    lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS(1u << 8)));

AllocaInst *alloc = dyn_cast<AllocaInst>(persistent_alloc);

MDNode *alloc_md = alloc->getMetadata("clang.decl.ptr");

if (!alloc_md || !alloc_md->getNumOperands())
  return false;

ConstantInt *constant_int =
    mdconst::dyn_extract<ConstantInt>(alloc_md->getOperand(0));

if (!constant_int)
  return false;

// We attempt to register this as a new persistent variable with the DeclMap.

uintptr_t ptr = constant_int->getZExtValue();

clang::VarDecl *decl = reinterpret_cast<clang::VarDecl *>(ptr);

lldb_private::TypeFromParser result_decl_type(
    m_decl_map->GetTypeSystem()->GetType(decl->getType()));

StringRef decl_name(decl->getName());
lldb_private::ConstString persistent_variable_name(decl_name.data(),
                                                   decl_name.size());
if (!m_decl_map->AddPersistentVariable(decl, persistent_variable_name,
                                       result_decl_type, false, false))
  return false;

GlobalVariable *persistent_global = new GlobalVariable(
    (*m_module), alloc->getType(), false,  /* not constant */
    GlobalValue::ExternalLinkage, nullptr, /* no initializer */
    alloc->getName().str());

// What we're going to do here is make believe this was a regular old
// external variable.  That means we need to make the metadata valid.

NamedMDNode *named_metadata =
    m_module->getOrInsertNamedMetadata("clang.global.decl.ptrs");

llvm::Metadata *values[2];
values[0] = ConstantAsMetadata::get(persistent_global);
values[1] = ConstantAsMetadata::get(constant_int);

ArrayRef<llvm::Metadata *> value_ref(values, 2);

MDNode *persistent_global_md = MDNode::get(m_module->getContext(), value_ref);
named_metadata->addOperand(persistent_global_md);

// Now, since the variable is a pointer variable, we will drop in a load of
// that pointer variable.

LoadInst *persistent_load =
    new LoadInst(persistent_global->getType()->getPointerElementType(),
                 persistent_global, "", alloc);

LLDB_LOG(log, "Replacing \"{0}\" with \"{1}\"", PrintValue(alloc),do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Replacing \"{0}\" with \"{1}\"", PrintValue(alloc
), PrintValue(persistent_load)); } while (0)
         PrintValue(persistent_load))do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Replacing \"{0}\" with \"{1}\"", PrintValue(alloc
), PrintValue(persistent_load)); } while (0);

alloc->replaceAllUsesWith(persistent_load);
alloc->eraseFromParent();

return true;
1126}

1128bool IRForTarget::RewritePersistentAllocs(llvm::BasicBlock &basic_block) {
if (!m_resolve_vars)
  return true;

lldb_private::Log *log(
    lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS(1u << 8)));

InstrList pvar_allocs;

for (Instruction &inst : basic_block) {

  if (AllocaInst *alloc = dyn_cast<AllocaInst>(&inst)) {
    llvm::StringRef alloc_name = alloc->getName();

    if (alloc_name.startswith("$") && !alloc_name.startswith("$__lldb")) {
      if (alloc_name.find_first_of("0123456789") == 1) {
        LLDB_LOG(log, "Rejecting a numeric persistent variable.")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Rejecting a numeric persistent variable."); } while
 (0);

        m_error_stream.Printf("Error [IRForTarget]: Names starting with $0, "
                              "$1, ... are reserved for use as result "
                              "names\n");

        return false;
      }

      pvar_allocs.push_back(alloc);
    }
  }
}

for (Instruction *inst : pvar_allocs) {
  if (!RewritePersistentAlloc(inst)) {
    m_error_stream.Printf("Internal error [IRForTarget]: Couldn't rewrite "
                          "the creation of a persistent variable\n");

    LLDB_LOG(log, "Couldn't rewrite the creation of a persistent variable")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Couldn't rewrite the creation of a persistent variable"
); } while (0);

    return false;
  }
}

return true;
1170}

1172// This function does not report errors; its callers are responsible.
1173bool IRForTarget::MaybeHandleVariable(Value *llvm_value_ptr) {
lldb_private::Log *log(
    lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS(1u << 8)));

LLDB_LOG(log, "MaybeHandleVariable ({0})", PrintValue(llvm_value_ptr))do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "MaybeHandleVariable ({0})", PrintValue(llvm_value_ptr
)); } while (0);

if (ConstantExpr *constant_expr = dyn_cast<ConstantExpr>(llvm_value_ptr)) {
  switch (constant_expr->getOpcode()) {
  default:
    break;
  case Instruction::GetElementPtr:
  case Instruction::BitCast:
    Value *s = constant_expr->getOperand(0);
    if (!MaybeHandleVariable(s))
      return false;
  }
} else if (GlobalVariable *global_variable =
               dyn_cast<GlobalVariable>(llvm_value_ptr)) {
  if (!GlobalValue::isExternalLinkage(global_variable->getLinkage()))
    return true;

  clang::NamedDecl *named_decl = DeclForGlobal(global_variable);

  if (!named_decl) {
    if (IsObjCSelectorRef(llvm_value_ptr))
      return true;

    if (!global_variable->hasExternalLinkage())
      return true;

    LLDB_LOG(log, "Found global variable \"{0}\" without metadata",do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Found global variable \"{0}\" without metadata",
 global_variable->getName()); } while (0)
             global_variable->getName())do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Found global variable \"{0}\" without metadata",
 global_variable->getName()); } while (0);

    return false;
  }

  llvm::StringRef name(named_decl->getName());

  clang::ValueDecl *value_decl = dyn_cast<clang::ValueDecl>(named_decl);
  if (value_decl == nullptr)
    return false;

  lldb_private::CompilerType compiler_type =
      m_decl_map->GetTypeSystem()->GetType(value_decl->getType());

  const Type *value_type = nullptr;

  if (name.startswith("$")) {
    // The $__lldb_expr_result name indicates the return value has allocated
    // as a static variable.  Per the comment at
    // ASTResultSynthesizer::SynthesizeBodyResult, accesses to this static
    // variable need to be redirected to the result of dereferencing a
    // pointer that is passed in as one of the arguments.
    //
    // Consequently, when reporting the size of the type, we report a pointer
    // type pointing to the type of $__lldb_expr_result, not the type itself.
    //
    // We also do this for any user-declared persistent variables.
    compiler_type = compiler_type.GetPointerType();
    value_type = PointerType::get(global_variable->getType(), 0);
  } else {
    value_type = global_variable->getType();
  }

  auto *target = m_execution_unit.GetTarget().get();
  llvm::Optional<uint64_t> value_size = compiler_type.GetByteSize(target);
  if (!value_size)
    return false;
  llvm::Optional<size_t> opt_alignment =
      compiler_type.GetTypeBitAlign(target);
  if (!opt_alignment)
    return false;
  lldb::offset_t value_alignment = (*opt_alignment + 7ull) / 8ull;

  LLDB_LOG(log,do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Type of \"{0}\" is [clang \"{1}\", llvm \"{2}\"] [size {3}, "
 "align {4}]", name, lldb_private::ClangUtil::GetQualType(compiler_type
).getAsString(), PrintType(value_type), *value_size, value_alignment
); } while (0)
           "Type of \"{0}\" is [clang \"{1}\", llvm \"{2}\"] [size {3}, "do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Type of \"{0}\" is [clang \"{1}\", llvm \"{2}\"] [size {3}, "
 "align {4}]", name, lldb_private::ClangUtil::GetQualType(compiler_type
).getAsString(), PrintType(value_type), *value_size, value_alignment
); } while (0)
           "align {4}]",do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Type of \"{0}\" is [clang \"{1}\", llvm \"{2}\"] [size {3}, "
 "align {4}]", name, lldb_private::ClangUtil::GetQualType(compiler_type
).getAsString(), PrintType(value_type), *value_size, value_alignment
); } while (0)
           name,do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Type of \"{0}\" is [clang \"{1}\", llvm \"{2}\"] [size {3}, "
 "align {4}]", name, lldb_private::ClangUtil::GetQualType(compiler_type
).getAsString(), PrintType(value_type), *value_size, value_alignment
); } while (0)
           lldb_private::ClangUtil::GetQualType(compiler_type).getAsString(),do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Type of \"{0}\" is [clang \"{1}\", llvm \"{2}\"] [size {3}, "
 "align {4}]", name, lldb_private::ClangUtil::GetQualType(compiler_type
).getAsString(), PrintType(value_type), *value_size, value_alignment
); } while (0)
           PrintType(value_type), *value_size, value_alignment)do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Type of \"{0}\" is [clang \"{1}\", llvm \"{2}\"] [size {3}, "
 "align {4}]", name, lldb_private::ClangUtil::GetQualType(compiler_type
).getAsString(), PrintType(value_type), *value_size, value_alignment
); } while (0);

  if (named_decl)
    m_decl_map->AddValueToStruct(named_decl, lldb_private::ConstString(name),
                                 llvm_value_ptr, *value_size,
                                 value_alignment);
} else if (dyn_cast<llvm::Function>(llvm_value_ptr)) {
  LLDB_LOG(log, "Function pointers aren't handled right now")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Function pointers aren't handled right now"); } while
 (0);

  return false;
}

return true;
1265}

1267// This function does not report errors; its callers are responsible.
1268bool IRForTarget::HandleSymbol(Value *symbol) {
lldb_private::Log *log(
    lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS(1u << 8)));

lldb_private::ConstString name(symbol->getName().str().c_str());

lldb::addr_t symbol_addr =
    m_decl_map->GetSymbolAddress(name, lldb::eSymbolTypeAny);

if (symbol_addr == LLDB_INVALID_ADDRESS0xffffffffffffffffULL) {
  LLDB_LOG(log, "Symbol \"{0}\" had no address", name)do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Symbol \"{0}\" had no address", name); } while (
0);

  return false;
}

LLDB_LOG(log, "Found \"{0}\" at {1}", name, symbol_addr)do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Found \"{0}\" at {1}", name, symbol_addr); } while
 (0);

Type *symbol_type = symbol->getType();

Constant *symbol_addr_int = ConstantInt::get(m_intptr_ty, symbol_addr, false);

Value *symbol_addr_ptr =
    ConstantExpr::getIntToPtr(symbol_addr_int, symbol_type);

LLDB_LOG(log, "Replacing {0} with {1}", PrintValue(symbol),do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Replacing {0} with {1}", PrintValue(symbol), PrintValue
(symbol_addr_ptr)); } while (0)
         PrintValue(symbol_addr_ptr))do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Replacing {0} with {1}", PrintValue(symbol), PrintValue
(symbol_addr_ptr)); } while (0);

symbol->replaceAllUsesWith(symbol_addr_ptr);

return true;
1298}

1300bool IRForTarget::MaybeHandleCallArguments(CallInst *Old) {
lldb_private::Log *log(
    lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS(1u << 8)));

LLDB_LOG(log, "MaybeHandleCallArguments({0})", PrintValue(Old))do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "MaybeHandleCallArguments({0})", PrintValue(Old))
; } while (0);

for (unsigned op_index = 0, num_ops = Old->getNumArgOperands();
     op_index < num_ops; ++op_index)
  // conservatively believe that this is a store
  if (!MaybeHandleVariable(Old->getArgOperand(op_index))) {
    m_error_stream.Printf("Internal error [IRForTarget]: Couldn't rewrite "
                          "one of the arguments of a function call.\n");

    return false;
  }

return true;
1317}

1319bool IRForTarget::HandleObjCClass(Value *classlist_reference) {
lldb_private::Log *log(
    lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS(1u << 8)));

GlobalVariable *global_variable =
    dyn_cast<GlobalVariable>(classlist_reference);

if (!global_variable)
  return false;

Constant *initializer = global_variable->getInitializer();

if (!initializer)
  return false;

if (!initializer->hasName())
  return false;

StringRef name(initializer->getName());
lldb_private::ConstString name_cstr(name.str().c_str());
lldb::addr_t class_ptr =
    m_decl_map->GetSymbolAddress(name_cstr, lldb::eSymbolTypeObjCClass);

LLDB_LOG(log, "Found reference to Objective-C class {0} ({1})", name,do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Found reference to Objective-C class {0} ({1})",
 name, (unsigned long long)class_ptr); } while (0)
         (unsigned long long)class_ptr)do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Found reference to Objective-C class {0} ({1})",
 name, (unsigned long long)class_ptr); } while (0);

if (class_ptr == LLDB_INVALID_ADDRESS0xffffffffffffffffULL)
  return false;

if (global_variable->use_empty())
  return false;

SmallVector<LoadInst *, 2> load_instructions;

for (llvm::User *u : global_variable->users()) {
  if (LoadInst *load_instruction = dyn_cast<LoadInst>(u))
    load_instructions.push_back(load_instruction);
}

if (load_instructions.empty())
  return false;

Constant *class_addr = ConstantInt::get(m_intptr_ty, (uint64_t)class_ptr);

for (LoadInst *load_instruction : load_instructions) {
  Constant *class_bitcast =
      ConstantExpr::getIntToPtr(class_addr, load_instruction->getType());

  load_instruction->replaceAllUsesWith(class_bitcast);

  load_instruction->eraseFromParent();
}

return true;
1373}

1375bool IRForTarget::RemoveCXAAtExit(BasicBlock &basic_block) {
std::vector<CallInst *> calls_to_remove;

for (Instruction &inst : basic_block) {
  CallInst *call = dyn_cast<CallInst>(&inst);

  // MaybeHandleCallArguments handles error reporting; we are silent here
  if (!call)
    continue;

  bool remove = false;

  llvm::Function *func = call->getCalledFunction();

  if (func && func->getName() == "__cxa_atexit")
    remove = true;

  llvm::Value *val = call->getCalledOperand();

  if (val && val->getName() == "__cxa_atexit")
    remove = true;

  if (remove)
    calls_to_remove.push_back(call);
}

for (CallInst *ci : calls_to_remove)
  ci->eraseFromParent();

return true;
1405}

1407bool IRForTarget::ResolveCalls(BasicBlock &basic_block) {
// Prepare the current basic block for execution in the remote process

for (Instruction &inst : basic_block) {
  CallInst *call = dyn_cast<CallInst>(&inst);

  // MaybeHandleCallArguments handles error reporting; we are silent here
  if (call && !MaybeHandleCallArguments(call))
    return false;
}

return true;
1419}

1421bool IRForTarget::ResolveExternals(Function &llvm_function) {
lldb_private::Log *log(
    lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS(1u << 8)));

for (GlobalVariable &global_var : m_module->globals()) {
  llvm::StringRef global_name = global_var.getName();

  LLDB_LOG(log, "Examining {0}, DeclForGlobalValue returns {1}", global_name,do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Examining {0}, DeclForGlobalValue returns {1}", global_name
, static_cast<void *>(DeclForGlobal(&global_var)));
 } while (0)
           static_cast<void *>(DeclForGlobal(&global_var)))do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Examining {0}, DeclForGlobalValue returns {1}", global_name
, static_cast<void *>(DeclForGlobal(&global_var)));
 } while (0);

  if (global_name.startswith("OBJC_IVAR")) {
    if (!HandleSymbol(&global_var)) {
      m_error_stream.Format("Error [IRForTarget]: Couldn't find Objective-C "
                            "indirect ivar symbol {0}\n",
                            global_name);

      return false;
    }
  } else if (global_name.contains("OBJC_CLASSLIST_REFERENCES_$")) {
    if (!HandleObjCClass(&global_var)) {
      m_error_stream.Printf("Error [IRForTarget]: Couldn't resolve the class "
                            "for an Objective-C static method call\n");

      return false;
    }
  } else if (global_name.contains("OBJC_CLASSLIST_SUP_REFS_$")) {
    if (!HandleObjCClass(&global_var)) {
      m_error_stream.Printf("Error [IRForTarget]: Couldn't resolve the class "
                            "for an Objective-C static method call\n");

      return false;
    }
  } else if (DeclForGlobal(&global_var)) {
    if (!MaybeHandleVariable(&global_var)) {
      m_error_stream.Format("Internal error [IRForTarget]: Couldn't rewrite "
                            "external variable {0}\n",
                            global_name);

      return false;
    }
  }
}

return true;
1465}

1467static bool isGuardVariableRef(Value *V) {
Constant *Old = dyn_cast<Constant>(V);

if (!Old)
  return false;

if (auto CE = dyn_cast<ConstantExpr>(V)) {
  if (CE->getOpcode() != Instruction::BitCast)
    return false;

  Old = CE->getOperand(0);
}

GlobalVariable *GV = dyn_cast<GlobalVariable>(Old);

if (!GV || !GV->hasName() || !isGuardVariableSymbol(GV->getName()))
  return false;

return true;
1486}

1488void IRForTarget::TurnGuardLoadIntoZero(llvm::Instruction *guard_load) {
Constant *zero(Constant::getNullValue(guard_load->getType()));
guard_load->replaceAllUsesWith(zero);
guard_load->eraseFromParent();
1492}

1494static void ExciseGuardStore(Instruction *guard_store) {
guard_store->eraseFromParent();
1496}

1498bool IRForTarget::RemoveGuards(BasicBlock &basic_block) {
// Eliminate any reference to guard variables found.

InstrList guard_loads;
InstrList guard_stores;

for (Instruction &inst : basic_block) {

  if (LoadInst *load = dyn_cast<LoadInst>(&inst))
    if (isGuardVariableRef(load->getPointerOperand()))
      guard_loads.push_back(&inst);

  if (StoreInst *store = dyn_cast<StoreInst>(&inst))
    if (isGuardVariableRef(store->getPointerOperand()))
      guard_stores.push_back(&inst);
}

for (Instruction *inst : guard_loads)
  TurnGuardLoadIntoZero(inst);

for (Instruction *inst : guard_stores)
  ExciseGuardStore(inst);

return true;
1522}

1524// This function does not report errors; its callers are responsible.
1525bool IRForTarget::UnfoldConstant(Constant *old_constant,
                               llvm::Function *llvm_function,
                               FunctionValueCache &value_maker,
                               FunctionValueCache &entry_instruction_finder,
                               lldb_private::Stream &error_stream) {
SmallVector<User *, 16> users;

// We do this because the use list might change, invalidating our iterator.
// Much better to keep a work list ourselves.
for (llvm::User *u : old_constant->users())
  users.push_back(u);

for (size_t i = 0; i < users.size(); ++i) {
  User *user = users[i];

  if (Constant *constant = dyn_cast<Constant>(user)) {
    // synthesize a new non-constant equivalent of the constant

    if (ConstantExpr *constant_expr = dyn_cast<ConstantExpr>(constant)) {
      switch (constant_expr->getOpcode()) {
      default:
        error_stream.Printf("error [IRForTarget internal]: Unhandled "
                            "constant expression type: \"%s\"",
                            PrintValue(constant_expr).c_str());
        return false;
      case Instruction::BitCast: {
        FunctionValueCache bit_cast_maker(
            [&value_maker, &entry_instruction_finder, old_constant,
             constant_expr](llvm::Function *function) -> llvm::Value * {
              // UnaryExpr
              //   OperandList[0] is value

              if (constant_expr->getOperand(0) != old_constant)
                return constant_expr;

              return new BitCastInst(
                  value_maker.GetValue(function), constant_expr->getType(),
                  "", llvm::cast<Instruction>(
                          entry_instruction_finder.GetValue(function)));
            });

        if (!UnfoldConstant(constant_expr, llvm_function, bit_cast_maker,
                            entry_instruction_finder, error_stream))
          return false;
      } break;
      case Instruction::GetElementPtr: {
        // GetElementPtrConstantExpr
        //   OperandList[0] is base
        //   OperandList[1]... are indices

        FunctionValueCache get_element_pointer_maker(
            [&value_maker, &entry_instruction_finder, old_constant,
             constant_expr](llvm::Function *function) -> llvm::Value * {
              auto *gep = cast<llvm::GEPOperator>(constant_expr);
              Value *ptr = gep->getPointerOperand();

              if (ptr == old_constant)
                ptr = value_maker.GetValue(function);

              std::vector<Value *> index_vector;
              for (Value *operand : gep->indices()) {
                if (operand == old_constant)
                  operand = value_maker.GetValue(function);

                index_vector.push_back(operand);
              }

              ArrayRef<Value *> indices(index_vector);

              return GetElementPtrInst::Create(
                  gep->getSourceElementType(), ptr, indices, "",
                  llvm::cast<Instruction>(
                      entry_instruction_finder.GetValue(function)));
            });

        if (!UnfoldConstant(constant_expr, llvm_function,
                            get_element_pointer_maker,
                            entry_instruction_finder, error_stream))
          return false;
      } break;
      }
    } else {
      error_stream.Printf(
          "error [IRForTarget internal]: Unhandled constant type: \"%s\"",
          PrintValue(constant).c_str());
      return false;
    }
  } else {
    if (Instruction *inst = llvm::dyn_cast<Instruction>(user)) {
      if (llvm_function && inst->getParent()->getParent() != llvm_function) {
        error_stream.PutCString("error: Capturing non-local variables in "
                                "expressions is unsupported.\n");
        return false;
      }
      inst->replaceUsesOfWith(
          old_constant, value_maker.GetValue(inst->getParent()->getParent()));
    } else {
      error_stream.Printf(
          "error [IRForTarget internal]: Unhandled non-constant type: \"%s\"",
          PrintValue(user).c_str());
      return false;
    }
  }
}

if (!isa<GlobalValue>(old_constant)) {
  old_constant->destroyConstant();
}

return true;
1635}

1637bool IRForTarget::ReplaceVariables(Function &llvm_function) {
if (!m_resolve_vars)
  return true;

lldb_private::Log *log(
    lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS(1u << 8)));

m_decl_map->DoStructLayout();

LLDB_LOG(log, "Element arrangement:")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Element arrangement:"); } while (0);

uint32_t num_elements;
uint32_t element_index;

size_t size;
lldb::offset_t alignment;

if (!m_decl_map->GetStructInfo(num_elements, size, alignment))
  return false;

Function::arg_iterator iter(llvm_function.arg_begin());

if (iter == llvm_function.arg_end()) {
  m_error_stream.Printf("Internal error [IRForTarget]: Wrapper takes no "
                        "arguments (should take at least a struct pointer)");

  return false;
}

Argument *argument = &*iter;

if (argument->getName().equals("this")) {
  ++iter;

  if (iter == llvm_function.arg_end()) {
    m_error_stream.Printf("Internal error [IRForTarget]: Wrapper takes only "
                          "'this' argument (should take a struct pointer "
                          "too)");

    return false;
  }

  argument = &*iter;
} else if (argument->getName().equals("self")) {
  ++iter;

  if (iter == llvm_function.arg_end()) {
    m_error_stream.Printf("Internal error [IRForTarget]: Wrapper takes only "
                          "'self' argument (should take '_cmd' and a struct "
                          "pointer too)");

    return false;
  }

  if (!iter->getName().equals("_cmd")) {
    m_error_stream.Format("Internal error [IRForTarget]: Wrapper takes '{0}' "
                          "after 'self' argument (should take '_cmd')",
                          iter->getName());

    return false;
  }

  ++iter;

  if (iter == llvm_function.arg_end()) {
    m_error_stream.Printf("Internal error [IRForTarget]: Wrapper takes only "
                          "'self' and '_cmd' arguments (should take a struct "
                          "pointer too)");

    return false;
  }

  argument = &*iter;
}

if (!argument->getName().equals("$__lldb_arg")) {
  m_error_stream.Format("Internal error [IRForTarget]: Wrapper takes an "
                        "argument named '{0}' instead of the struct pointer",
                        argument->getName());

  return false;
}

LLDB_LOG(log, "Arg: \"{0}\"", PrintValue(argument))do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Arg: \"{0}\"", PrintValue(argument)); } while (0
);

BasicBlock &entry_block(llvm_function.getEntryBlock());
Instruction *FirstEntryInstruction(entry_block.getFirstNonPHIOrDbg());

if (!FirstEntryInstruction) {
  m_error_stream.Printf("Internal error [IRForTarget]: Couldn't find the "
                        "first instruction in the wrapper for use in "
                        "rewriting");

  return false;
}

LLVMContext &context(m_module->getContext());
IntegerType *offset_type(Type::getInt32Ty(context));

if (!offset_type) {
  m_error_stream.Printf(
      "Internal error [IRForTarget]: Couldn't produce an offset type");

  return false;
}

for (element_index = 0; element_index < num_elements; ++element_index) {
  const clang::NamedDecl *decl = nullptr;
  Value *value = nullptr;
  lldb::offset_t offset;
  lldb_private::ConstString name;

  if (!m_decl_map->GetStructElement(decl, value, offset, name,
                                    element_index)) {
    m_error_stream.Printf(
        "Internal error [IRForTarget]: Structure information is incomplete");

    return false;
  }

  LLDB_LOG(log, "  \"{0}\" (\"{1}\") placed at {2}", name,do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "  \"{0}\" (\"{1}\") placed at {2}", name, decl->
getNameAsString(), offset); } while (0)
           decl->getNameAsString(), offset)do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "  \"{0}\" (\"{1}\") placed at {2}", name, decl->
getNameAsString(), offset); } while (0);

  if (value) {
    LLDB_LOG(log, "    Replacing [{0}]", PrintValue(value))do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "    Replacing [{0}]", PrintValue(value)); } while
 (0);

    FunctionValueCache body_result_maker(
        [this, name, offset_type, offset, argument,
         value](llvm::Function *function) -> llvm::Value * {
          // Per the comment at ASTResultSynthesizer::SynthesizeBodyResult,
          // in cases where the result variable is an rvalue, we have to
          // synthesize a dereference of the appropriate structure entry in
          // order to produce the static variable that the AST thinks it is
          // accessing.

          llvm::Instruction *entry_instruction = llvm::cast<Instruction>(
              m_entry_instruction_finder.GetValue(function));

          ConstantInt *offset_int(
              ConstantInt::get(offset_type, offset, true));
          GetElementPtrInst *get_element_ptr = GetElementPtrInst::Create(
              argument->getType()->getPointerElementType(), argument,
              offset_int, "", entry_instruction);

          if (name == m_result_name && !m_result_is_pointer) {
            BitCastInst *bit_cast = new BitCastInst(
                get_element_ptr, value->getType()->getPointerTo(), "",
                entry_instruction);

            LoadInst *load =
                new LoadInst(bit_cast->getType()->getPointerElementType(),
                             bit_cast, "", entry_instruction);

            return load;
          } else {
            BitCastInst *bit_cast = new BitCastInst(
                get_element_ptr, value->getType(), "", entry_instruction);

            return bit_cast;
          }
        });

    if (Constant *constant = dyn_cast<Constant>(value)) {
      if (!UnfoldConstant(constant, &llvm_function, body_result_maker,
                          m_entry_instruction_finder, m_error_stream)) {
        return false;
      }
    } else if (Instruction *instruction = dyn_cast<Instruction>(value)) {
      if (instruction->getParent()->getParent() != &llvm_function) {
        m_error_stream.PutCString("error: Capturing non-local variables in "
                                  "expressions is unsupported.\n");
        return false;
      }
      value->replaceAllUsesWith(
          body_result_maker.GetValue(instruction->getParent()->getParent()));
    } else {
      LLDB_LOG(log, "Unhandled non-constant type: \"{0}\"",do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Unhandled non-constant type: \"{0}\"", PrintValue
(value)); } while (0)
               PrintValue(value))do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Unhandled non-constant type: \"{0}\"", PrintValue
(value)); } while (0);
      return false;
    }

    if (GlobalVariable *var = dyn_cast<GlobalVariable>(value))
      var->eraseFromParent();
  }
}

LLDB_LOG(log, "Total structure [align {0}, size {1}]", (int64_t)alignment,do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Total structure [align {0}, size {1}]", (int64_t
)alignment, (uint64_t)size); } while (0)
         (uint64_t)size)do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Total structure [align {0}, size {1}]", (int64_t
)alignment, (uint64_t)size); } while (0);

return true;
1827}

1829bool IRForTarget::runOnModule(Module &llvm_module) {
lldb_private::Log *log(
    lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS(1u << 8)));

m_module = &llvm_module;
m_target_data = std::make_unique<DataLayout>(m_module);
m_intptr_ty = llvm::Type::getIntNTy(m_module->getContext(),
                                    m_target_data->getPointerSizeInBits());

if (log) {
1
Assuming 'log' is null→
2
←
Taking false branch→
  std::string s;
  raw_string_ostream oss(s);

  m_module->print(oss, nullptr);

  oss.flush();

  LLDB_LOG(log, "Module as passed in to IRForTarget: \n\"{0}\"", s)do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Module as passed in to IRForTarget: \n\"{0}\"", s
); } while (0);
}

Function *const main_function =
    m_func_name.IsEmpty() ? nullptr
3
←
'?' condition is false→
                          : m_module->getFunction(m_func_name.GetStringRef());

if (!m_func_name.IsEmpty() && !main_function) {
4
←
Assuming 'main_function' is non-null→
5
←
Taking false branch→
  LLDB_LOG(log, "Couldn't find \"{0}()\" in the module", m_func_name)do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Couldn't find \"{0}()\" in the module", m_func_name
); } while (0);

  m_error_stream.Format("Internal error [IRForTarget]: Couldn't find wrapper "
                        "'{0}' in the module",
                        m_func_name);

  return false;
}

if (main_function5.1
'main_function' is non-null
1
'main_function' is non-null
) {
6
←
Taking true branch→
  if (!FixFunctionLinkage(*main_function)) {
7
←
Taking false branch→
    LLDB_LOG(log, "Couldn't fix the linkage for the function")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Couldn't fix the linkage for the function"); } while
 (0);

    return false;
  }
}

llvm::Type *int8_ty = Type::getInt8Ty(m_module->getContext());

m_reloc_placeholder = new llvm::GlobalVariable(
    (*m_module), int8_ty, false /* IsConstant */,
    GlobalVariable::InternalLinkage, Constant::getNullValue(int8_ty),
    "reloc_placeholder", nullptr /* InsertBefore */,
    GlobalVariable::NotThreadLocal /* ThreadLocal */, 0 /* AddressSpace */);

////////////////////////////////////////////////////////////
// Replace $__lldb_expr_result with a persistent variable
//

if (main_function7.1
'main_function' is non-null
1
'main_function' is non-null
) {
8
←
Taking true branch→
  if (!CreateResultVariable(*main_function)) {
9
←
Assuming the condition is false→
10
←
Taking false branch→
    LLDB_LOG(log, "CreateResultVariable() failed")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "CreateResultVariable() failed"); } while (0);

    // CreateResultVariable() reports its own errors, so we don't do so here

    return false;
  }
}

if (log10.1
'log' is null
1
'log' is null
 && log->GetVerbose()) {
  std::string s;
  raw_string_ostream oss(s);

  m_module->print(oss, nullptr);

  oss.flush();

  LLDB_LOG(log, "Module after creating the result variable: \n\"{0}\"", s)do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Module after creating the result variable: \n\"{0}\""
, s); } while (0);
}

for (llvm::Function &function : *m_module) {
  for (BasicBlock &bb : function) {
    if (!RemoveGuards(bb)) {
      LLDB_LOG(log, "RemoveGuards() failed")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "RemoveGuards() failed"); } while (0);

      // RemoveGuards() reports its own errors, so we don't do so here

      return false;
    }

    if (!RewritePersistentAllocs(bb)) {
      LLDB_LOG(log, "RewritePersistentAllocs() failed")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "RewritePersistentAllocs() failed"); } while (0);

      // RewritePersistentAllocs() reports its own errors, so we don't do so
      // here

      return false;
    }

    if (!RemoveCXAAtExit(bb)) {
      LLDB_LOG(log, "RemoveCXAAtExit() failed")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "RemoveCXAAtExit() failed"); } while (0);

      // RemoveCXAAtExit() reports its own errors, so we don't do so here

      return false;
    }
  }
}

///////////////////////////////////////////////////////////////////////////////
// Fix all Objective-C constant strings to use NSStringWithCString:encoding:
//

if (!RewriteObjCConstStrings()) {
11
←
Taking false branch→
  LLDB_LOG(log, "RewriteObjCConstStrings() failed")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "RewriteObjCConstStrings() failed"); } while (0);

  // RewriteObjCConstStrings() reports its own errors, so we don't do so here

  return false;
}

for (llvm::Function &function : *m_module) {
  for (llvm::BasicBlock &bb : function) {
    if (!RewriteObjCSelectors(bb)) {
12
←
Calling 'IRForTarget::RewriteObjCSelectors'→
      LLDB_LOG(log, "RewriteObjCSelectors() failed")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "RewriteObjCSelectors() failed"); } while (0);

      // RewriteObjCSelectors() reports its own errors, so we don't do so
      // here

      return false;
    }

    if (!RewriteObjCClassReferences(bb)) {
      LLDB_LOG(log, "RewriteObjCClassReferences() failed")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "RewriteObjCClassReferences() failed"); } while (
0);

      // RewriteObjCClasses() reports its own errors, so we don't do so here

      return false;
    }
  }
}

for (llvm::Function &function : *m_module) {
  for (BasicBlock &bb : function) {
    if (!ResolveCalls(bb)) {
      LLDB_LOG(log, "ResolveCalls() failed")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "ResolveCalls() failed"); } while (0);

      // ResolveCalls() reports its own errors, so we don't do so here

      return false;
    }
  }
}

////////////////////////////////////////////////////////////////////////
// Run function-level passes that only make sense on the main function
//

if (main_function) {
  if (!ResolveExternals(*main_function)) {
    LLDB_LOG(log, "ResolveExternals() failed")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "ResolveExternals() failed"); } while (0);

    // ResolveExternals() reports its own errors, so we don't do so here

    return false;
  }

  if (!ReplaceVariables(*main_function)) {
    LLDB_LOG(log, "ReplaceVariables() failed")do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "ReplaceVariables() failed"); } while (0);

    // ReplaceVariables() reports its own errors, so we don't do so here

    return false;
  }
}

if (log && log->GetVerbose()) {
  std::string s;
  raw_string_ostream oss(s);

  m_module->print(oss, nullptr);

  oss.flush();

  LLDB_LOG(log, "Module after preparing for execution: \n\"{0}\"", s)do { ::lldb_private::Log *log_private = (log); if (log_private
) log_private->Format("/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp"
, __func__, "Module after preparing for execution: \n\"{0}\""
, s); } while (0);
}

return true;
2012}

←

/usr/src/gnu/usr.bin/clang/liblldbPluginExpressionParser/../../../llvm/llvm/include/llvm/IR/GlobalVariable.h

1//===-- llvm/GlobalVariable.h - GlobalVariable class ------------*- 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 contains the declaration of the GlobalVariable class, which
10// represents a single global variable (or constant) in the VM.
11//
12// Global variables are constant pointers that refer to hunks of space that are
13// allocated by either the VM, or by the linker in a static compiler.  A global
14// variable may have an initial value, which is copied into the executables .data
15// area.  Global Constants are required to have initializers.
16//
17//===----------------------------------------------------------------------===//

19#ifndef LLVM_IR_GLOBALVARIABLE_H
20#define LLVM_IR_GLOBALVARIABLE_H

22#include "llvm/ADT/Twine.h"
23#include "llvm/ADT/ilist_node.h"
24#include "llvm/IR/Attributes.h"
25#include "llvm/IR/GlobalObject.h"
26#include "llvm/IR/OperandTraits.h"
27#include "llvm/IR/Value.h"
28#include <cassert>
29#include <cstddef>

31namespace llvm {

33class Constant;
34class Module;

36template <typename ValueSubClass> class SymbolTableListTraits;
37class DIGlobalVariable;
38class DIGlobalVariableExpression;

40class GlobalVariable : public GlobalObject, public ilist_node<GlobalVariable> {
friend class SymbolTableListTraits<GlobalVariable>;

AttributeSet Attrs;
bool isConstantGlobal : 1;                   // Is this a global constant?
bool isExternallyInitializedConstant : 1;    // Is this a global whose value
                                             // can change from its initial
                                             // value before global
                                             // initializers are run?

50public:
/// GlobalVariable ctor - If a parent module is specified, the global is
/// automatically inserted into the end of the specified modules global list.
GlobalVariable(Type *Ty, bool isConstant, LinkageTypes Linkage,
               Constant *Initializer = nullptr, const Twine &Name = "",
               ThreadLocalMode = NotThreadLocal, unsigned AddressSpace = 0,
               bool isExternallyInitialized = false);
/// GlobalVariable ctor - This creates a global and inserts it before the
/// specified other global.
GlobalVariable(Module &M, Type *Ty, bool isConstant, LinkageTypes Linkage,
               Constant *Initializer, const Twine &Name = "",
               GlobalVariable *InsertBefore = nullptr,
               ThreadLocalMode = NotThreadLocal,
               Optional<unsigned> AddressSpace = None,
               bool isExternallyInitialized = false);
GlobalVariable(const GlobalVariable &) = delete;
GlobalVariable &operator=(const GlobalVariable &) = delete;

~GlobalVariable() {
  dropAllReferences();
}

// allocate space for exactly one operand
void *operator new(size_t s) {
  return User::operator new(s, 1);
}

// delete space for exactly one operand as created in the corresponding new operator
void operator delete(void *ptr){
  assert(ptr != nullptr && "must not be nullptr")((void)0);
  User *Obj = static_cast<User *>(ptr);
  // Number of operands can be set to 0 after construction and initialization. Make sure
  // that number of operands is reset to 1, as this is needed in User::operator delete
  Obj->setGlobalVariableNumOperands(1);
  User::operator delete(Obj);
}

/// Provide fast operand accessors
DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value)public: inline Value *getOperand(unsigned) const; inline void
 setOperand(unsigned, Value*); inline op_iterator op_begin();
 inline const_op_iterator op_begin() const; inline op_iterator
 op_end(); inline const_op_iterator op_end() const; protected
: template <int> inline Use &Op(); template <int
> inline const Use &Op() const; public: inline unsigned
 getNumOperands() const;

/// Definitions have initializers, declarations don't.
///
inline bool hasInitializer() const { return !isDeclaration(); }
19
←
Assuming the condition is true→
20
←
Returning the value 1, which participates in a condition later→
29
←
Assuming the condition is true→
30
←
Returning the value 1, which participates in a condition later→

/// hasDefinitiveInitializer - Whether the global variable has an initializer,
/// and any other instances of the global (this can happen due to weak
/// linkage) are guaranteed to have the same initializer.
///
/// Note that if you want to transform a global, you must use
/// hasUniqueInitializer() instead, because of the *_odr linkage type.
///
/// Example:
///
/// @a = global SomeType* null - Initializer is both definitive and unique.
///
/// @b = global weak SomeType* null - Initializer is neither definitive nor
/// unique.
///
/// @c = global weak_odr SomeType* null - Initializer is definitive, but not
/// unique.
inline bool hasDefinitiveInitializer() const {
  return hasInitializer() &&
    // The initializer of a global variable may change to something arbitrary
    // at link time.
    !isInterposable() &&
    // The initializer of a global variable with the externally_initialized
    // marker may change at runtime before C++ initializers are evaluated.
    !isExternallyInitialized();
}

/// hasUniqueInitializer - Whether the global variable has an initializer, and
/// any changes made to the initializer will turn up in the final executable.
inline bool hasUniqueInitializer() const {
  return
      // We need to be sure this is the definition that will actually be used
      isStrongDefinitionForLinker() &&
      // It is not safe to modify initializers of global variables with the
      // external_initializer marker since the value may be changed at runtime
      // before C++ initializers are evaluated.
      !isExternallyInitialized();
}

/// getInitializer - Return the initializer for this global variable.  It is
/// illegal to call this method if the global is external, because we cannot
/// tell what the value is initialized to!
///
inline const Constant *getInitializer() const {
  assert(hasInitializer() && "GV doesn't have initializer!")((void)0);
  return static_cast<Constant*>(Op<0>().get());
}
inline Constant *getInitializer() {
  assert(hasInitializer() && "GV doesn't have initializer!")((void)0);
  return static_cast<Constant*>(Op<0>().get());
}
/// setInitializer - Sets the initializer for this global variable, removing
/// any existing initializer if InitVal==NULL.  If this GV has type T*, the
/// initializer must have type T.
void setInitializer(Constant *InitVal);

/// If the value is a global constant, its value is immutable throughout the
/// runtime execution of the program.  Assigning a value into the constant
/// leads to undefined behavior.
///
bool isConstant() const { return isConstantGlobal; }
void setConstant(bool Val) { isConstantGlobal = Val; }

bool isExternallyInitialized() const {
  return isExternallyInitializedConstant;
}
void setExternallyInitialized(bool Val) {
  isExternallyInitializedConstant = Val;
}

/// copyAttributesFrom - copy all additional attributes (those not needed to
/// create a GlobalVariable) from the GlobalVariable Src to this one.
void copyAttributesFrom(const GlobalVariable *Src);

/// removeFromParent - This method unlinks 'this' from the containing module,
/// but does not delete it.
///
void removeFromParent();

/// eraseFromParent - This method unlinks 'this' from the containing module
/// and deletes it.
///
void eraseFromParent();

/// Drop all references in preparation to destroy the GlobalVariable. This
/// drops not only the reference to the initializer but also to any metadata.
void dropAllReferences();

/// Attach a DIGlobalVariableExpression.
void addDebugInfo(DIGlobalVariableExpression *GV);

/// Fill the vector with all debug info attachements.
void getDebugInfo(SmallVectorImpl<DIGlobalVariableExpression *> &GVs) const;

/// Add attribute to this global.
void addAttribute(Attribute::AttrKind Kind) {
  Attrs = Attrs.addAttribute(getContext(), Kind);
}

/// Add attribute to this global.
void addAttribute(StringRef Kind, StringRef Val = StringRef()) {
  Attrs = Attrs.addAttribute(getContext(), Kind, Val);
}

/// Return true if the attribute exists.
bool hasAttribute(Attribute::AttrKind Kind) const {
  return Attrs.hasAttribute(Kind);
}

/// Return true if the attribute exists.
bool hasAttribute(StringRef Kind) const {
  return Attrs.hasAttribute(Kind);
}

/// Return true if any attributes exist.
bool hasAttributes() const {
  return Attrs.hasAttributes();
}

/// Return the attribute object.
Attribute getAttribute(Attribute::AttrKind Kind) const {
  return Attrs.getAttribute(Kind);
}

/// Return the attribute object.
Attribute getAttribute(StringRef Kind) const {
  return Attrs.getAttribute(Kind);
}

/// Return the attribute set for this global
AttributeSet getAttributes() const {
  return Attrs;
}

/// Return attribute set as list with index.
/// FIXME: This may not be required once ValueEnumerators
/// in bitcode-writer can enumerate attribute-set.
AttributeList getAttributesAsList(unsigned index) const {
  if (!hasAttributes())
    return AttributeList();
  std::pair<unsigned, AttributeSet> AS[1] = {{index, Attrs}};
  return AttributeList::get(getContext(), AS);
}

/// Set attribute list for this global
void setAttributes(AttributeSet A) {
  Attrs = A;
}

/// Check if section name is present
bool hasImplicitSection() const {
  return getAttributes().hasAttribute("bss-section") ||
         getAttributes().hasAttribute("data-section") ||
         getAttributes().hasAttribute("relro-section") ||
         getAttributes().hasAttribute("rodata-section");
}

// Methods for support type inquiry through isa, cast, and dyn_cast:
static bool classof(const Value *V) {
  return V->getValueID() == Value::GlobalVariableVal;
}
254};

256template <>
257struct OperandTraits<GlobalVariable> :
public OptionalOperandTraits<GlobalVariable> {
259};

261DEFINE_TRANSPARENT_OPERAND_ACCESSORS(GlobalVariable, Value)GlobalVariable::op_iterator GlobalVariable::op_begin() { return
 OperandTraits<GlobalVariable>::op_begin(this); } GlobalVariable
::const_op_iterator GlobalVariable::op_begin() const { return
 OperandTraits<GlobalVariable>::op_begin(const_cast<
GlobalVariable*>(this)); } GlobalVariable::op_iterator GlobalVariable
::op_end() { return OperandTraits<GlobalVariable>::op_end
(this); } GlobalVariable::const_op_iterator GlobalVariable::op_end
() const { return OperandTraits<GlobalVariable>::op_end
(const_cast<GlobalVariable*>(this)); } Value *GlobalVariable
::getOperand(unsigned i_nocapture) const { ((void)0); return cast_or_null
<Value>( OperandTraits<GlobalVariable>::op_begin(
const_cast<GlobalVariable*>(this))[i_nocapture].get());
 } void GlobalVariable::setOperand(unsigned i_nocapture, Value
 *Val_nocapture) { ((void)0); OperandTraits<GlobalVariable
>::op_begin(this)[i_nocapture] = Val_nocapture; } unsigned
 GlobalVariable::getNumOperands() const { return OperandTraits
<GlobalVariable>::operands(this); } template <int Idx_nocapture
> Use &GlobalVariable::Op() { return this->OpFrom<
Idx_nocapture>(this); } template <int Idx_nocapture>
 const Use &GlobalVariable::Op() const { return this->
OpFrom<Idx_nocapture>(this); }

263} // end namespace llvm

265#endif // LLVM_IR_GLOBALVARIABLE_H