clang  6.0.0svn
Enumerations | Functions
CGBlocks.cpp File Reference
#include "CGBlocks.h"
#include "CGDebugInfo.h"
#include "CGObjCRuntime.h"
#include "CGOpenCLRuntime.h"
#include "CodeGenFunction.h"
#include "CodeGenModule.h"
#include "ConstantEmitter.h"
#include "TargetInfo.h"
#include "clang/AST/DeclObjC.h"
#include "clang/CodeGen/ConstantInitBuilder.h"
#include "llvm/ADT/SmallSet.h"
#include "llvm/IR/CallSite.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/Module.h"
#include <algorithm>
#include <cstdio>
Include dependency graph for CGBlocks.cpp:

Go to the source code of this file.

Enumerations

enum  BlockCaptureEntityKind
 Represents a type of copy/destroy operation that should be performed for an entity that's captured by a block. More...
 

Functions

static llvm::Constant * buildGlobalBlock (CodeGenModule &CGM, const CGBlockInfo &blockInfo, llvm::Constant *blockFn)
 Build the given block as a global block. More...
 
static llvm::Constant * buildCopyHelper (CodeGenModule &CGM, const CGBlockInfo &blockInfo)
 Build the helper function to copy a block. More...
 
static llvm::Constant * buildDisposeHelper (CodeGenModule &CGM, const CGBlockInfo &blockInfo)
 Build the helper function to dispose of a block. More...
 
static llvm::Constant * buildBlockDescriptor (CodeGenModule &CGM, const CGBlockInfo &blockInfo)
 buildBlockDescriptor - Build the block descriptor meta-data for a block. More...
 
static bool isSafeForCXXConstantCapture (QualType type)
 Determines if the given type is safe for constant capture in C++. More...
 
static llvm::Constant * tryCaptureAsConstant (CodeGenModule &CGM, CodeGenFunction *CGF, const VarDecl *var)
 It is illegal to modify a const object after initialization. More...
 
static CharUnits getLowBit (CharUnits v)
 Get the low bit of a nonzero character count. More...
 
static void initializeForBlockHeader (CodeGenModule &CGM, CGBlockInfo &info, SmallVectorImpl< llvm::Type *> &elementTypes)
 
static QualType getCaptureFieldType (const CodeGenFunction &CGF, const BlockDecl::Capture &CI)
 
static void computeBlockInfo (CodeGenModule &CGM, CodeGenFunction *CGF, CGBlockInfo &info)
 Compute the layout of the given block. More...
 
static void enterBlockScope (CodeGenFunction &CGF, BlockDecl *block)
 Enter the scope of a block. More...
 
static CGBlockInfofindAndRemoveBlockInfo (CGBlockInfo **head, const BlockDecl *block)
 Find the layout for the given block in a linked list and remove it. More...
 
static std::pair< BlockCaptureEntityKind, BlockFieldFlagscomputeCopyInfoForBlockCapture (const BlockDecl::Capture &CI, QualType T, const LangOptions &LangOpts)
 
static void findBlockCapturedManagedEntities (const CGBlockInfo &BlockInfo, const LangOptions &LangOpts, SmallVectorImpl< BlockCaptureManagedEntity > &ManagedCaptures, llvm::function_ref< std::pair< BlockCaptureEntityKind, BlockFieldFlags >(const BlockDecl::Capture &, QualType, const LangOptions &)> Predicate)
 Find the set of block captures that need to be explicitly copied or destroy. More...
 
static std::pair< BlockCaptureEntityKind, BlockFieldFlagscomputeDestroyInfoForBlockCapture (const BlockDecl::Capture &CI, QualType T, const LangOptions &LangOpts)
 
static llvm::Constant * generateByrefCopyHelper (CodeGenFunction &CGF, const BlockByrefInfo &byrefInfo, BlockByrefHelpers &generator)
 
static llvm::Constant * buildByrefCopyHelper (CodeGenModule &CGM, const BlockByrefInfo &byrefInfo, BlockByrefHelpers &generator)
 Build the copy helper for a __block variable. More...
 
static llvm::Constant * generateByrefDisposeHelper (CodeGenFunction &CGF, const BlockByrefInfo &byrefInfo, BlockByrefHelpers &generator)
 Generate code for a __block variable's dispose helper. More...
 
static llvm::Constant * buildByrefDisposeHelper (CodeGenModule &CGM, const BlockByrefInfo &byrefInfo, BlockByrefHelpers &generator)
 Build the dispose helper for a __block variable. More...
 
template<class T >
static T * buildByrefHelpers (CodeGenModule &CGM, const BlockByrefInfo &byrefInfo, T &&generator)
 Lazily build the copy and dispose helpers for a __block variable with the given information. More...
 
static void configureBlocksRuntimeObject (CodeGenModule &CGM, llvm::Constant *C)
 Adjust the declaration of something from the blocks API. More...
 

Enumeration Type Documentation

◆ BlockCaptureEntityKind

Represents a type of copy/destroy operation that should be performed for an entity that's captured by a block.

Definition at line 1512 of file CGBlocks.cpp.

Function Documentation

◆ buildBlockDescriptor()

static llvm::Constant* buildBlockDescriptor ( CodeGenModule CGM,
const CGBlockInfo blockInfo 
)
static

buildBlockDescriptor - Build the block descriptor meta-data for a block.

buildBlockDescriptor is accessed from 5th field of the Block_literal meta-data and contains stationary information about the block literal. Its definition will have 4 (or optinally 6) words.

struct Block_descriptor {
unsigned long reserved;
unsigned long size; // size of Block_literal metadata in bytes.
void *copy_func_helper_decl; // optional copy helper.
void *destroy_func_decl; // optioanl destructor helper.
void *block_method_encoding_address; // @encode for block literal signature.
void *block_layout_info; // encoding of captured block variables.
};

Definition at line 80 of file CGBlocks.cpp.

References clang::CodeGen::ConstantInitBuilderTemplateBase< Traits >::beginStruct(), clang::CodeGen::CGBlockInfo::BlockSize, buildCopyHelper(), buildDisposeHelper(), clang::CodeGen::CGObjCRuntime::BuildGCBlockLayout(), clang::CodeGen::CGObjCRuntime::BuildRCBlockLayout(), clang::CodeGen::CGBlockInfo::Captures, clang::CodeGen::CodeGenTypes::ConvertType(), clang::CodeGen::CGBlockInfo::CXXThisIndex, clang::CodeGen::CGBlockInfo::CXXThisOffset, clang::CodeGen::CodeGenModule::GetAddrOfConstantCString(), clang::CodeGen::CodeGenModule::getBlockDescriptorType(), clang::CodeGen::CGBlockInfo::getBlockExpr(), clang::CodeGen::CodeGenModule::getContext(), clang::CodeGen::CodeGenModule::getLangOpts(), clang::ASTContext::getLangOpts(), clang::CodeGen::CodeGenModule::getLLVMContext(), clang::ASTContext::getObjCEncodingForBlock(), clang::CodeGen::CodeGenModule::getObjCRuntime(), clang::CodeGen::ConstantAddress::getPointer(), clang::CodeGen::CodeGenTypeCache::getPointerAlign(), clang::CharUnits::getQuantity(), clang::ASTContext::getTargetAddressSpace(), clang::CodeGen::CodeGenModule::getTypes(), clang::BlockDecl::Capture::getVariable(), clang::InternalLinkage, clang::CodeGen::CGBlockInfo::Capture::makeIndex(), clang::CodeGen::CGBlockInfo::NeedsCopyDispose, clang::LangOptions::NonGC, clang::Qualifiers::OCL_Strong, clang::Qualifiers::OCL_Weak, clang::opencl_constant, clang::operator<(), clang::CodeGen::Type, clang::ASTContext::UnsignedLongTy, and clang::CodeGen::CodeGenTypeCache::VoidPtrTy.

Referenced by buildGlobalBlock(), and clang::CodeGen::CodeGenFunction::EmitBlockLiteral().

◆ buildByrefCopyHelper()

static llvm::Constant* buildByrefCopyHelper ( CodeGenModule CGM,
const BlockByrefInfo byrefInfo,
BlockByrefHelpers generator 
)
static

Build the copy helper for a __block variable.

Definition at line 2094 of file CGBlocks.cpp.

References generateByrefCopyHelper().

Referenced by buildByrefHelpers().

◆ buildByrefDisposeHelper()

static llvm::Constant* buildByrefDisposeHelper ( CodeGenModule CGM,
const BlockByrefInfo byrefInfo,
BlockByrefHelpers generator 
)
static

Build the dispose helper for a __block variable.

Definition at line 2156 of file CGBlocks.cpp.

References generateByrefDisposeHelper().

Referenced by buildByrefHelpers().

◆ buildByrefHelpers()

template<class T >
static T* buildByrefHelpers ( CodeGenModule CGM,
const BlockByrefInfo byrefInfo,
T &&  generator 
)
static

◆ buildCopyHelper()

static llvm::Constant* buildCopyHelper ( CodeGenModule CGM,
const CGBlockInfo blockInfo 
)
static

Build the helper function to copy a block.

Definition at line 55 of file CGBlocks.cpp.

References clang::CodeGen::CodeGenFunction::GenerateCopyHelperFunction().

Referenced by buildBlockDescriptor().

◆ buildDisposeHelper()

static llvm::Constant* buildDisposeHelper ( CodeGenModule CGM,
const CGBlockInfo blockInfo 
)
static

Build the helper function to dispose of a block.

Definition at line 61 of file CGBlocks.cpp.

References clang::CodeGen::CodeGenFunction::GenerateDestroyHelperFunction().

Referenced by buildBlockDescriptor().

◆ buildGlobalBlock()

static llvm::Constant * buildGlobalBlock ( CodeGenModule CGM,
const CGBlockInfo blockInfo,
llvm::Constant *  blockFn 
)
static

◆ computeBlockInfo()

static void computeBlockInfo ( CodeGenModule CGM,
CodeGenFunction CGF,
CGBlockInfo info 
)
static

Compute the layout of the given block.

Attempts to lay the block out with minimal space requirements.

Definition at line 375 of file CGBlocks.cpp.

References clang::CharUnits::alignTo(), clang::CodeGen::CGBlockInfo::BlockAlign, clang::CodeGen::CGBlockInfo::BlockHeaderForcedGapOffset, clang::CodeGen::CGBlockInfo::BlockHeaderForcedGapSize, clang::CodeGen::CGBlockInfo::BlockSize, clang::CodeGen::CGBlockInfo::CanBeGlobal, clang::BlockDecl::capture_begin(), clang::BlockDecl::capture_end(), clang::CodeGen::CGBlockInfo::Captures, clang::BlockDecl::captures(), clang::BlockDecl::capturesCXXThis(), clang::CodeGen::CodeGenTypes::ConvertType(), clang::CodeGen::CodeGenTypes::ConvertTypeForMem(), clang::CodeGen::CodeGenFunction::CurFuncDecl, clang::Type::getAsCXXRecordDecl(), clang::CodeGen::CGBlockInfo::getBlockDecl(), getCaptureFieldType(), clang::CodeGen::CodeGenModule::getContext(), clang::ASTContext::getDeclAlign(), clang::CodeGen::CodeGenModule::getLangOpts(), clang::ASTContext::getLangOpts(), clang::CodeGen::CodeGenModule::getLLVMContext(), getLowBit(), clang::QualType::getObjCLifetime(), clang::CodeGen::CodeGenTypeCache::getPointerAlign(), clang::CodeGen::CodeGenTypeCache::getPointerSize(), clang::CharUnits::getQuantity(), clang::CodeGen::CodeGenModule::getTargetCodeGenInfo(), clang::CodeGen::TargetCodeGenInfo::getTargetOpenCLBlockHelper(), clang::ValueDecl::getType(), clang::ASTContext::getTypeInfoInChars(), clang::CodeGen::CodeGenModule::getTypes(), clang::ASTContext::getTypeSizeInChars(), clang::CodeGen::CGBlockInfo::HasCapturedVariableLayout, clang::BlockDecl::hasCaptures(), clang::CodeGen::CGBlockInfo::HasCXXObject, initializeForBlockHeader(), clang::CodeGen::CodeGenTypeCache::Int8Ty, clang::Type::isObjCInertUnsafeUnretainedType(), clang::Type::isObjCRetainableType(), clang::CodeGen::CGBlockInfo::Capture::makeConstant(), max(), clang::CodeGen::CGBlockInfo::NeedsCopyDispose, clang::LangOptions::NonGC, clang::Qualifiers::OCL_Autoreleasing, clang::Qualifiers::OCL_ExplicitNone, clang::Qualifiers::OCL_None, clang::Qualifiers::OCL_Strong, clang::Qualifiers::OCL_Weak, clang::CodeGen::CGBlockInfo::StructureType, tryCaptureAsConstant(), clang::CodeGen::Type, clang::CodeGen::CodeGenTypeCache::VoidPtrTy, and clang::CharUnits::Zero().

Referenced by clang::CodeGen::CodeGenFunction::EmitBlockLiteral(), enterBlockScope(), and clang::CodeGen::CodeGenModule::GetAddrOfGlobalBlock().

◆ computeCopyInfoForBlockCapture()

static std::pair<BlockCaptureEntityKind, BlockFieldFlags> computeCopyInfoForBlockCapture ( const BlockDecl::Capture CI,
QualType  T,
const LangOptions LangOpts 
)
static

◆ computeDestroyInfoForBlockCapture()

static std::pair<BlockCaptureEntityKind, BlockFieldFlags> computeDestroyInfoForBlockCapture ( const BlockDecl::Capture CI,
QualType  T,
const LangOptions LangOpts 
)
static

◆ configureBlocksRuntimeObject()

static void configureBlocksRuntimeObject ( CodeGenModule CGM,
llvm::Constant *  C 
)
static

◆ enterBlockScope()

static void enterBlockScope ( CodeGenFunction CGF,
BlockDecl block 
)
static

Enter the scope of a block.

This should be run at the entrance to a full-expression so that the block's cleanups are pushed at the right place in the stack.

Definition at line 621 of file CGBlocks.cpp.

References clang::CodeGen::CodeGenFunction::Builder, clang::BlockDecl::captures(), clang::CodeGen::CGBlockInfo::CGBlockInfo(), clang::CodeGen::CodeGenFunction::CGM, computeBlockInfo(), clang::CodeGen::CGBuilderTy::CreateStructGEP(), clang::CodeGen::CodeGenFunction::CreateTempAlloca(), clang::CodeGen::CodeGenFunction::CurFn, clang::CodeGen::CodeGenFunction::destroyARCStrongImprecise, clang::QualType::DK_none, clang::QualType::DK_objc_strong_lifetime, clang::CodeGen::CodeGenFunction::EHStack, clang::CodeGen::CodeGenFunction::emitARCIntrinsicUse, clang::CodeGen::CodeGenFunction::FirstBlockInfo, getCaptureFieldType(), clang::CodeGen::CodeGenModule::getCodeGenOpts(), clang::CodeGen::CodeGenFunction::getDestroyer(), clang::CodeGen::CGBlockInfo::Capture::getIndex(), clang::CodeGen::CodeGenModule::getLangOpts(), clang::QualType::getObjCLifetime(), clang::CodeGen::CGBlockInfo::Capture::getOffset(), clang::CodeGen::Address::getPointer(), clang::CodeGen::CodeGenFunction::HaveInsertPoint(), clang::CodeGen::InactiveNormalAndEHCleanup, clang::CodeGen::InactiveNormalCleanup, clang::CodeGen::CGBlockInfo::Capture::isConstant(), clang::QualType::isConstQualified(), clang::QualType::isDestructedType(), clang::CodeGen::CodeGenFunction::needsEHCleanup(), clang::Qualifiers::OCL_Strong, clang::CodeGen::CodeGenFunction::pushDestroy(), clang::CodeGen::CGBlockInfo::Capture::setCleanup(), and clang::CodeGen::EHScopeStack::stable_begin().

◆ findAndRemoveBlockInfo()

static CGBlockInfo* findAndRemoveBlockInfo ( CGBlockInfo **  head,
const BlockDecl block 
)
static

Find the layout for the given block in a linked list and remove it.

Definition at line 716 of file CGBlocks.cpp.

References clang::CodeGen::CGBlockInfo::getBlockDecl(), and clang::CodeGen::CGBlockInfo::NextBlockInfo.

Referenced by clang::CodeGen::CodeGenFunction::EmitBlockLiteral().

◆ findBlockCapturedManagedEntities()

static void findBlockCapturedManagedEntities ( const CGBlockInfo BlockInfo,
const LangOptions LangOpts,
SmallVectorImpl< BlockCaptureManagedEntity > &  ManagedCaptures,
llvm::function_ref< std::pair< BlockCaptureEntityKind, BlockFieldFlags >(const BlockDecl::Capture &, QualType, const LangOptions &)>  Predicate 
)
static

◆ generateByrefCopyHelper()

static llvm::Constant* generateByrefCopyHelper ( CodeGenFunction CGF,
const BlockByrefInfo byrefInfo,
BlockByrefHelpers generator 
)
static

Definition at line 2026 of file CGBlocks.cpp.

Referenced by buildByrefCopyHelper().

◆ generateByrefDisposeHelper()

static llvm::Constant* generateByrefDisposeHelper ( CodeGenFunction CGF,
const BlockByrefInfo byrefInfo,
BlockByrefHelpers generator 
)
static

Generate code for a __block variable's dispose helper.

Definition at line 2103 of file CGBlocks.cpp.

Referenced by buildByrefDisposeHelper().

◆ getCaptureFieldType()

static QualType getCaptureFieldType ( const CodeGenFunction CGF,
const BlockDecl::Capture CI 
)
static

◆ getLowBit()

static CharUnits getLowBit ( CharUnits  v)
static

Get the low bit of a nonzero character count.

This is the alignment of the nth byte if the 0th byte is universally aligned.

Definition at line 301 of file CGBlocks.cpp.

References clang::CharUnits::fromQuantity(), and clang::CharUnits::getQuantity().

Referenced by computeBlockInfo().

◆ initializeForBlockHeader()

static void initializeForBlockHeader ( CodeGenModule CGM,
CGBlockInfo info,
SmallVectorImpl< llvm::Type *> &  elementTypes 
)
static

◆ isSafeForCXXConstantCapture()

static bool isSafeForCXXConstantCapture ( QualType  type)
static

Determines if the given type is safe for constant capture in C++.

Definition at line 245 of file CGBlocks.cpp.

References clang::Type::getAs(), clang::Type::getBaseElementTypeUnsafe(), clang::RecordType::getDecl(), and clang::ast_matchers::recordType.

Referenced by tryCaptureAsConstant().

◆ tryCaptureAsConstant()

static llvm::Constant* tryCaptureAsConstant ( CodeGenModule CGM,
CodeGenFunction CGF,
const VarDecl var 
)
static

It is illegal to modify a const object after initialization.

Therefore, if a const object has a constant initializer, we don't actually need to keep storage for it in the block; we'll just rematerialize it at the start of the block function. This is acceptable because we make no promises about address stability of captured variables.

Definition at line 269 of file CGBlocks.cpp.

References clang::VarDecl::getInit(), clang::CodeGen::CodeGenModule::getLangOpts(), clang::ValueDecl::getType(), clang::QualType::isConstQualified(), isSafeForCXXConstantCapture(), and clang::CodeGen::ConstantEmitter::tryEmitAbstractForInitializer().

Referenced by computeBlockInfo().