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2369 lines
86 KiB
2369 lines
86 KiB
//===--- CGBlocks.cpp - Emit LLVM Code for declarations ---------*- C++ -*-===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This contains code to emit blocks.
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//
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//===----------------------------------------------------------------------===//
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#include "CGBlocks.h"
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#include "CGDebugInfo.h"
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#include "CGObjCRuntime.h"
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#include "CodeGenFunction.h"
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#include "CodeGenModule.h"
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#include "clang/AST/DeclObjC.h"
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#include "llvm/ADT/SmallSet.h"
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#include "llvm/IR/CallSite.h"
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#include "llvm/IR/DataLayout.h"
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#include "llvm/IR/Module.h"
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#include <algorithm>
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#include <cstdio>
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using namespace clang;
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using namespace CodeGen;
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CGBlockInfo::CGBlockInfo(const BlockDecl *block, StringRef name)
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: Name(name), CXXThisIndex(0), CanBeGlobal(false), NeedsCopyDispose(false),
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HasCXXObject(false), UsesStret(false), HasCapturedVariableLayout(false),
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LocalAddress(Address::invalid()), StructureType(nullptr), Block(block),
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DominatingIP(nullptr) {
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// Skip asm prefix, if any. 'name' is usually taken directly from
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// the mangled name of the enclosing function.
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if (!name.empty() && name[0] == '\01')
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name = name.substr(1);
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}
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// Anchor the vtable to this translation unit.
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BlockByrefHelpers::~BlockByrefHelpers() {}
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/// Build the given block as a global block.
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static llvm::Constant *buildGlobalBlock(CodeGenModule &CGM,
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const CGBlockInfo &blockInfo,
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llvm::Constant *blockFn);
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/// Build the helper function to copy a block.
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static llvm::Constant *buildCopyHelper(CodeGenModule &CGM,
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const CGBlockInfo &blockInfo) {
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return CodeGenFunction(CGM).GenerateCopyHelperFunction(blockInfo);
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}
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/// Build the helper function to dispose of a block.
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static llvm::Constant *buildDisposeHelper(CodeGenModule &CGM,
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const CGBlockInfo &blockInfo) {
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return CodeGenFunction(CGM).GenerateDestroyHelperFunction(blockInfo);
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}
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/// buildBlockDescriptor - Build the block descriptor meta-data for a block.
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/// buildBlockDescriptor is accessed from 5th field of the Block_literal
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/// meta-data and contains stationary information about the block literal.
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/// Its definition will have 4 (or optinally 6) words.
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/// \code
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/// struct Block_descriptor {
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/// unsigned long reserved;
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/// unsigned long size; // size of Block_literal metadata in bytes.
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/// void *copy_func_helper_decl; // optional copy helper.
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/// void *destroy_func_decl; // optioanl destructor helper.
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/// void *block_method_encoding_address; // @encode for block literal signature.
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/// void *block_layout_info; // encoding of captured block variables.
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/// };
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/// \endcode
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static llvm::Constant *buildBlockDescriptor(CodeGenModule &CGM,
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const CGBlockInfo &blockInfo) {
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ASTContext &C = CGM.getContext();
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llvm::Type *ulong = CGM.getTypes().ConvertType(C.UnsignedLongTy);
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llvm::Type *i8p = nullptr;
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if (CGM.getLangOpts().OpenCL)
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i8p =
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llvm::Type::getInt8PtrTy(
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CGM.getLLVMContext(), C.getTargetAddressSpace(LangAS::opencl_constant));
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else
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i8p = CGM.getTypes().ConvertType(C.VoidPtrTy);
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SmallVector<llvm::Constant*, 6> elements;
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// reserved
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elements.push_back(llvm::ConstantInt::get(ulong, 0));
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// Size
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// FIXME: What is the right way to say this doesn't fit? We should give
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// a user diagnostic in that case. Better fix would be to change the
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// API to size_t.
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elements.push_back(llvm::ConstantInt::get(ulong,
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blockInfo.BlockSize.getQuantity()));
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// Optional copy/dispose helpers.
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if (blockInfo.NeedsCopyDispose) {
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// copy_func_helper_decl
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elements.push_back(buildCopyHelper(CGM, blockInfo));
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// destroy_func_decl
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elements.push_back(buildDisposeHelper(CGM, blockInfo));
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}
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// Signature. Mandatory ObjC-style method descriptor @encode sequence.
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std::string typeAtEncoding =
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CGM.getContext().getObjCEncodingForBlock(blockInfo.getBlockExpr());
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elements.push_back(llvm::ConstantExpr::getBitCast(
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CGM.GetAddrOfConstantCString(typeAtEncoding).getPointer(), i8p));
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// GC layout.
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if (C.getLangOpts().ObjC1) {
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if (CGM.getLangOpts().getGC() != LangOptions::NonGC)
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elements.push_back(CGM.getObjCRuntime().BuildGCBlockLayout(CGM, blockInfo));
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else
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elements.push_back(CGM.getObjCRuntime().BuildRCBlockLayout(CGM, blockInfo));
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}
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else
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elements.push_back(llvm::Constant::getNullValue(i8p));
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llvm::Constant *init = llvm::ConstantStruct::getAnon(elements);
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llvm::GlobalVariable *global =
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new llvm::GlobalVariable(CGM.getModule(), init->getType(), true,
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llvm::GlobalValue::InternalLinkage,
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init, "__block_descriptor_tmp");
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return llvm::ConstantExpr::getBitCast(global, CGM.getBlockDescriptorType());
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}
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/*
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Purely notional variadic template describing the layout of a block.
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template <class _ResultType, class... _ParamTypes, class... _CaptureTypes>
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struct Block_literal {
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/// Initialized to one of:
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/// extern void *_NSConcreteStackBlock[];
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/// extern void *_NSConcreteGlobalBlock[];
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///
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/// In theory, we could start one off malloc'ed by setting
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/// BLOCK_NEEDS_FREE, giving it a refcount of 1, and using
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/// this isa:
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/// extern void *_NSConcreteMallocBlock[];
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struct objc_class *isa;
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/// These are the flags (with corresponding bit number) that the
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/// compiler is actually supposed to know about.
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/// 25. BLOCK_HAS_COPY_DISPOSE - indicates that the block
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/// descriptor provides copy and dispose helper functions
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/// 26. BLOCK_HAS_CXX_OBJ - indicates that there's a captured
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/// object with a nontrivial destructor or copy constructor
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/// 28. BLOCK_IS_GLOBAL - indicates that the block is allocated
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/// as global memory
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/// 29. BLOCK_USE_STRET - indicates that the block function
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/// uses stret, which objc_msgSend needs to know about
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/// 30. BLOCK_HAS_SIGNATURE - indicates that the block has an
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/// @encoded signature string
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/// And we're not supposed to manipulate these:
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/// 24. BLOCK_NEEDS_FREE - indicates that the block has been moved
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/// to malloc'ed memory
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/// 27. BLOCK_IS_GC - indicates that the block has been moved to
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/// to GC-allocated memory
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/// Additionally, the bottom 16 bits are a reference count which
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/// should be zero on the stack.
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int flags;
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/// Reserved; should be zero-initialized.
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int reserved;
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/// Function pointer generated from block literal.
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_ResultType (*invoke)(Block_literal *, _ParamTypes...);
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/// Block description metadata generated from block literal.
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struct Block_descriptor *block_descriptor;
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/// Captured values follow.
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_CapturesTypes captures...;
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};
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*/
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/// The number of fields in a block header.
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const unsigned BlockHeaderSize = 5;
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namespace {
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/// A chunk of data that we actually have to capture in the block.
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struct BlockLayoutChunk {
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CharUnits Alignment;
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CharUnits Size;
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Qualifiers::ObjCLifetime Lifetime;
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const BlockDecl::Capture *Capture; // null for 'this'
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llvm::Type *Type;
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BlockLayoutChunk(CharUnits align, CharUnits size,
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Qualifiers::ObjCLifetime lifetime,
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const BlockDecl::Capture *capture,
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llvm::Type *type)
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: Alignment(align), Size(size), Lifetime(lifetime),
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Capture(capture), Type(type) {}
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/// Tell the block info that this chunk has the given field index.
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void setIndex(CGBlockInfo &info, unsigned index, CharUnits offset) {
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if (!Capture) {
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info.CXXThisIndex = index;
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info.CXXThisOffset = offset;
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} else {
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info.Captures.insert({Capture->getVariable(),
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CGBlockInfo::Capture::makeIndex(index, offset)});
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}
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}
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};
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/// Order by 1) all __strong together 2) next, all byfref together 3) next,
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/// all __weak together. Preserve descending alignment in all situations.
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bool operator<(const BlockLayoutChunk &left, const BlockLayoutChunk &right) {
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if (left.Alignment != right.Alignment)
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return left.Alignment > right.Alignment;
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auto getPrefOrder = [](const BlockLayoutChunk &chunk) {
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if (chunk.Capture && chunk.Capture->isByRef())
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return 1;
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if (chunk.Lifetime == Qualifiers::OCL_Strong)
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return 0;
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if (chunk.Lifetime == Qualifiers::OCL_Weak)
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return 2;
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return 3;
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};
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return getPrefOrder(left) < getPrefOrder(right);
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}
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} // end anonymous namespace
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/// Determines if the given type is safe for constant capture in C++.
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static bool isSafeForCXXConstantCapture(QualType type) {
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const RecordType *recordType =
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type->getBaseElementTypeUnsafe()->getAs<RecordType>();
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// Only records can be unsafe.
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if (!recordType) return true;
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const auto *record = cast<CXXRecordDecl>(recordType->getDecl());
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// Maintain semantics for classes with non-trivial dtors or copy ctors.
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if (!record->hasTrivialDestructor()) return false;
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if (record->hasNonTrivialCopyConstructor()) return false;
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// Otherwise, we just have to make sure there aren't any mutable
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// fields that might have changed since initialization.
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return !record->hasMutableFields();
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}
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/// It is illegal to modify a const object after initialization.
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/// Therefore, if a const object has a constant initializer, we don't
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/// actually need to keep storage for it in the block; we'll just
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/// rematerialize it at the start of the block function. This is
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/// acceptable because we make no promises about address stability of
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/// captured variables.
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static llvm::Constant *tryCaptureAsConstant(CodeGenModule &CGM,
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CodeGenFunction *CGF,
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const VarDecl *var) {
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// Return if this is a function paramter. We shouldn't try to
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// rematerialize default arguments of function parameters.
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if (isa<ParmVarDecl>(var))
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return nullptr;
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QualType type = var->getType();
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// We can only do this if the variable is const.
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if (!type.isConstQualified()) return nullptr;
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// Furthermore, in C++ we have to worry about mutable fields:
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// C++ [dcl.type.cv]p4:
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// Except that any class member declared mutable can be
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// modified, any attempt to modify a const object during its
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// lifetime results in undefined behavior.
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if (CGM.getLangOpts().CPlusPlus && !isSafeForCXXConstantCapture(type))
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return nullptr;
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// If the variable doesn't have any initializer (shouldn't this be
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// invalid?), it's not clear what we should do. Maybe capture as
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// zero?
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const Expr *init = var->getInit();
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if (!init) return nullptr;
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return CGM.EmitConstantInit(*var, CGF);
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}
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/// Get the low bit of a nonzero character count. This is the
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/// alignment of the nth byte if the 0th byte is universally aligned.
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static CharUnits getLowBit(CharUnits v) {
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return CharUnits::fromQuantity(v.getQuantity() & (~v.getQuantity() + 1));
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}
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static void initializeForBlockHeader(CodeGenModule &CGM, CGBlockInfo &info,
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SmallVectorImpl<llvm::Type*> &elementTypes) {
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// The header is basically 'struct { void *; int; int; void *; void *; }'.
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// Assert that that struct is packed.
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assert(CGM.getIntSize() <= CGM.getPointerSize());
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assert(CGM.getIntAlign() <= CGM.getPointerAlign());
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assert((2 * CGM.getIntSize()).isMultipleOf(CGM.getPointerAlign()));
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info.BlockAlign = CGM.getPointerAlign();
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info.BlockSize = 3 * CGM.getPointerSize() + 2 * CGM.getIntSize();
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assert(elementTypes.empty());
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elementTypes.push_back(CGM.VoidPtrTy);
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elementTypes.push_back(CGM.IntTy);
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elementTypes.push_back(CGM.IntTy);
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elementTypes.push_back(CGM.VoidPtrTy);
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elementTypes.push_back(CGM.getBlockDescriptorType());
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assert(elementTypes.size() == BlockHeaderSize);
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}
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/// Compute the layout of the given block. Attempts to lay the block
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/// out with minimal space requirements.
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static void computeBlockInfo(CodeGenModule &CGM, CodeGenFunction *CGF,
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CGBlockInfo &info) {
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ASTContext &C = CGM.getContext();
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const BlockDecl *block = info.getBlockDecl();
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SmallVector<llvm::Type*, 8> elementTypes;
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initializeForBlockHeader(CGM, info, elementTypes);
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if (!block->hasCaptures()) {
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info.StructureType =
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llvm::StructType::get(CGM.getLLVMContext(), elementTypes, true);
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info.CanBeGlobal = true;
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return;
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}
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else if (C.getLangOpts().ObjC1 &&
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CGM.getLangOpts().getGC() == LangOptions::NonGC)
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info.HasCapturedVariableLayout = true;
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// Collect the layout chunks.
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SmallVector<BlockLayoutChunk, 16> layout;
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layout.reserve(block->capturesCXXThis() +
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(block->capture_end() - block->capture_begin()));
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CharUnits maxFieldAlign;
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// First, 'this'.
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if (block->capturesCXXThis()) {
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assert(CGF && CGF->CurFuncDecl && isa<CXXMethodDecl>(CGF->CurFuncDecl) &&
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"Can't capture 'this' outside a method");
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QualType thisType = cast<CXXMethodDecl>(CGF->CurFuncDecl)->getThisType(C);
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// Theoretically, this could be in a different address space, so
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// don't assume standard pointer size/align.
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llvm::Type *llvmType = CGM.getTypes().ConvertType(thisType);
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std::pair<CharUnits,CharUnits> tinfo
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= CGM.getContext().getTypeInfoInChars(thisType);
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maxFieldAlign = std::max(maxFieldAlign, tinfo.second);
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layout.push_back(BlockLayoutChunk(tinfo.second, tinfo.first,
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Qualifiers::OCL_None,
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nullptr, llvmType));
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}
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// Next, all the block captures.
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for (const auto &CI : block->captures()) {
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const VarDecl *variable = CI.getVariable();
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if (CI.isByRef()) {
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// We have to copy/dispose of the __block reference.
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info.NeedsCopyDispose = true;
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// Just use void* instead of a pointer to the byref type.
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CharUnits align = CGM.getPointerAlign();
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maxFieldAlign = std::max(maxFieldAlign, align);
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layout.push_back(BlockLayoutChunk(align, CGM.getPointerSize(),
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Qualifiers::OCL_None, &CI,
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CGM.VoidPtrTy));
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continue;
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}
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// Otherwise, build a layout chunk with the size and alignment of
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// the declaration.
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if (llvm::Constant *constant = tryCaptureAsConstant(CGM, CGF, variable)) {
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info.Captures[variable] = CGBlockInfo::Capture::makeConstant(constant);
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continue;
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}
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// If we have a lifetime qualifier, honor it for capture purposes.
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// That includes *not* copying it if it's __unsafe_unretained.
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Qualifiers::ObjCLifetime lifetime =
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variable->getType().getObjCLifetime();
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if (lifetime) {
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switch (lifetime) {
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case Qualifiers::OCL_None: llvm_unreachable("impossible");
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case Qualifiers::OCL_ExplicitNone:
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case Qualifiers::OCL_Autoreleasing:
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break;
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case Qualifiers::OCL_Strong:
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case Qualifiers::OCL_Weak:
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info.NeedsCopyDispose = true;
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}
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// Block pointers require copy/dispose. So do Objective-C pointers.
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} else if (variable->getType()->isObjCRetainableType()) {
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// But honor the inert __unsafe_unretained qualifier, which doesn't
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// actually make it into the type system.
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if (variable->getType()->isObjCInertUnsafeUnretainedType()) {
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lifetime = Qualifiers::OCL_ExplicitNone;
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} else {
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info.NeedsCopyDispose = true;
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// used for mrr below.
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lifetime = Qualifiers::OCL_Strong;
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}
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// So do types that require non-trivial copy construction.
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} else if (CI.hasCopyExpr()) {
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info.NeedsCopyDispose = true;
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info.HasCXXObject = true;
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// And so do types with destructors.
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} else if (CGM.getLangOpts().CPlusPlus) {
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if (const CXXRecordDecl *record =
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variable->getType()->getAsCXXRecordDecl()) {
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if (!record->hasTrivialDestructor()) {
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info.HasCXXObject = true;
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info.NeedsCopyDispose = true;
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}
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}
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}
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QualType VT = variable->getType();
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CharUnits size = C.getTypeSizeInChars(VT);
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CharUnits align = C.getDeclAlign(variable);
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maxFieldAlign = std::max(maxFieldAlign, align);
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llvm::Type *llvmType =
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CGM.getTypes().ConvertTypeForMem(VT);
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layout.push_back(BlockLayoutChunk(align, size, lifetime, &CI, llvmType));
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}
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// If that was everything, we're done here.
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if (layout.empty()) {
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info.StructureType =
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llvm::StructType::get(CGM.getLLVMContext(), elementTypes, true);
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info.CanBeGlobal = true;
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return;
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}
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// Sort the layout by alignment. We have to use a stable sort here
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// to get reproducible results. There should probably be an
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// llvm::array_pod_stable_sort.
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std::stable_sort(layout.begin(), layout.end());
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// Needed for blocks layout info.
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info.BlockHeaderForcedGapOffset = info.BlockSize;
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info.BlockHeaderForcedGapSize = CharUnits::Zero();
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CharUnits &blockSize = info.BlockSize;
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info.BlockAlign = std::max(maxFieldAlign, info.BlockAlign);
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// Assuming that the first byte in the header is maximally aligned,
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// get the alignment of the first byte following the header.
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CharUnits endAlign = getLowBit(blockSize);
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// If the end of the header isn't satisfactorily aligned for the
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// maximum thing, look for things that are okay with the header-end
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// alignment, and keep appending them until we get something that's
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// aligned right. This algorithm is only guaranteed optimal if
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// that condition is satisfied at some point; otherwise we can get
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// things like:
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// header // next byte has alignment 4
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// something_with_size_5; // next byte has alignment 1
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// something_with_alignment_8;
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// which has 7 bytes of padding, as opposed to the naive solution
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// which might have less (?).
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if (endAlign < maxFieldAlign) {
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SmallVectorImpl<BlockLayoutChunk>::iterator
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li = layout.begin() + 1, le = layout.end();
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|
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// Look for something that the header end is already
|
|
// satisfactorily aligned for.
|
|
for (; li != le && endAlign < li->Alignment; ++li)
|
|
;
|
|
|
|
// If we found something that's naturally aligned for the end of
|
|
// the header, keep adding things...
|
|
if (li != le) {
|
|
SmallVectorImpl<BlockLayoutChunk>::iterator first = li;
|
|
for (; li != le; ++li) {
|
|
assert(endAlign >= li->Alignment);
|
|
|
|
li->setIndex(info, elementTypes.size(), blockSize);
|
|
elementTypes.push_back(li->Type);
|
|
blockSize += li->Size;
|
|
endAlign = getLowBit(blockSize);
|
|
|
|
// ...until we get to the alignment of the maximum field.
|
|
if (endAlign >= maxFieldAlign) {
|
|
break;
|
|
}
|
|
}
|
|
// Don't re-append everything we just appended.
|
|
layout.erase(first, li);
|
|
}
|
|
}
|
|
|
|
assert(endAlign == getLowBit(blockSize));
|
|
|
|
// At this point, we just have to add padding if the end align still
|
|
// isn't aligned right.
|
|
if (endAlign < maxFieldAlign) {
|
|
CharUnits newBlockSize = blockSize.alignTo(maxFieldAlign);
|
|
CharUnits padding = newBlockSize - blockSize;
|
|
|
|
// If we haven't yet added any fields, remember that there was an
|
|
// initial gap; this need to go into the block layout bit map.
|
|
if (blockSize == info.BlockHeaderForcedGapOffset) {
|
|
info.BlockHeaderForcedGapSize = padding;
|
|
}
|
|
|
|
elementTypes.push_back(llvm::ArrayType::get(CGM.Int8Ty,
|
|
padding.getQuantity()));
|
|
blockSize = newBlockSize;
|
|
endAlign = getLowBit(blockSize); // might be > maxFieldAlign
|
|
}
|
|
|
|
assert(endAlign >= maxFieldAlign);
|
|
assert(endAlign == getLowBit(blockSize));
|
|
// Slam everything else on now. This works because they have
|
|
// strictly decreasing alignment and we expect that size is always a
|
|
// multiple of alignment.
|
|
for (SmallVectorImpl<BlockLayoutChunk>::iterator
|
|
li = layout.begin(), le = layout.end(); li != le; ++li) {
|
|
if (endAlign < li->Alignment) {
|
|
// size may not be multiple of alignment. This can only happen with
|
|
// an over-aligned variable. We will be adding a padding field to
|
|
// make the size be multiple of alignment.
|
|
CharUnits padding = li->Alignment - endAlign;
|
|
elementTypes.push_back(llvm::ArrayType::get(CGM.Int8Ty,
|
|
padding.getQuantity()));
|
|
blockSize += padding;
|
|
endAlign = getLowBit(blockSize);
|
|
}
|
|
assert(endAlign >= li->Alignment);
|
|
li->setIndex(info, elementTypes.size(), blockSize);
|
|
elementTypes.push_back(li->Type);
|
|
blockSize += li->Size;
|
|
endAlign = getLowBit(blockSize);
|
|
}
|
|
|
|
info.StructureType =
|
|
llvm::StructType::get(CGM.getLLVMContext(), elementTypes, true);
|
|
}
|
|
|
|
/// 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.
|
|
static void enterBlockScope(CodeGenFunction &CGF, BlockDecl *block) {
|
|
assert(CGF.HaveInsertPoint());
|
|
|
|
// Allocate the block info and place it at the head of the list.
|
|
CGBlockInfo &blockInfo =
|
|
*new CGBlockInfo(block, CGF.CurFn->getName());
|
|
blockInfo.NextBlockInfo = CGF.FirstBlockInfo;
|
|
CGF.FirstBlockInfo = &blockInfo;
|
|
|
|
// Compute information about the layout, etc., of this block,
|
|
// pushing cleanups as necessary.
|
|
computeBlockInfo(CGF.CGM, &CGF, blockInfo);
|
|
|
|
// Nothing else to do if it can be global.
|
|
if (blockInfo.CanBeGlobal) return;
|
|
|
|
// Make the allocation for the block.
|
|
blockInfo.LocalAddress = CGF.CreateTempAlloca(blockInfo.StructureType,
|
|
blockInfo.BlockAlign, "block");
|
|
|
|
// If there are cleanups to emit, enter them (but inactive).
|
|
if (!blockInfo.NeedsCopyDispose) return;
|
|
|
|
// Walk through the captures (in order) and find the ones not
|
|
// captured by constant.
|
|
for (const auto &CI : block->captures()) {
|
|
// Ignore __block captures; there's nothing special in the
|
|
// on-stack block that we need to do for them.
|
|
if (CI.isByRef()) continue;
|
|
|
|
// Ignore variables that are constant-captured.
|
|
const VarDecl *variable = CI.getVariable();
|
|
CGBlockInfo::Capture &capture = blockInfo.getCapture(variable);
|
|
if (capture.isConstant()) continue;
|
|
|
|
// Ignore objects that aren't destructed.
|
|
QualType::DestructionKind dtorKind =
|
|
variable->getType().isDestructedType();
|
|
if (dtorKind == QualType::DK_none) continue;
|
|
|
|
CodeGenFunction::Destroyer *destroyer;
|
|
|
|
// Block captures count as local values and have imprecise semantics.
|
|
// They also can't be arrays, so need to worry about that.
|
|
if (dtorKind == QualType::DK_objc_strong_lifetime) {
|
|
destroyer = CodeGenFunction::destroyARCStrongImprecise;
|
|
} else {
|
|
destroyer = CGF.getDestroyer(dtorKind);
|
|
}
|
|
|
|
// GEP down to the address.
|
|
Address addr = CGF.Builder.CreateStructGEP(blockInfo.LocalAddress,
|
|
capture.getIndex(),
|
|
capture.getOffset());
|
|
|
|
// We can use that GEP as the dominating IP.
|
|
if (!blockInfo.DominatingIP)
|
|
blockInfo.DominatingIP = cast<llvm::Instruction>(addr.getPointer());
|
|
|
|
CleanupKind cleanupKind = InactiveNormalCleanup;
|
|
bool useArrayEHCleanup = CGF.needsEHCleanup(dtorKind);
|
|
if (useArrayEHCleanup)
|
|
cleanupKind = InactiveNormalAndEHCleanup;
|
|
|
|
CGF.pushDestroy(cleanupKind, addr, variable->getType(),
|
|
destroyer, useArrayEHCleanup);
|
|
|
|
// Remember where that cleanup was.
|
|
capture.setCleanup(CGF.EHStack.stable_begin());
|
|
}
|
|
}
|
|
|
|
/// Enter a full-expression with a non-trivial number of objects to
|
|
/// clean up. This is in this file because, at the moment, the only
|
|
/// kind of cleanup object is a BlockDecl*.
|
|
void CodeGenFunction::enterNonTrivialFullExpression(const ExprWithCleanups *E) {
|
|
assert(E->getNumObjects() != 0);
|
|
ArrayRef<ExprWithCleanups::CleanupObject> cleanups = E->getObjects();
|
|
for (ArrayRef<ExprWithCleanups::CleanupObject>::iterator
|
|
i = cleanups.begin(), e = cleanups.end(); i != e; ++i) {
|
|
enterBlockScope(*this, *i);
|
|
}
|
|
}
|
|
|
|
/// Find the layout for the given block in a linked list and remove it.
|
|
static CGBlockInfo *findAndRemoveBlockInfo(CGBlockInfo **head,
|
|
const BlockDecl *block) {
|
|
while (true) {
|
|
assert(head && *head);
|
|
CGBlockInfo *cur = *head;
|
|
|
|
// If this is the block we're looking for, splice it out of the list.
|
|
if (cur->getBlockDecl() == block) {
|
|
*head = cur->NextBlockInfo;
|
|
return cur;
|
|
}
|
|
|
|
head = &cur->NextBlockInfo;
|
|
}
|
|
}
|
|
|
|
/// Destroy a chain of block layouts.
|
|
void CodeGenFunction::destroyBlockInfos(CGBlockInfo *head) {
|
|
assert(head && "destroying an empty chain");
|
|
do {
|
|
CGBlockInfo *cur = head;
|
|
head = cur->NextBlockInfo;
|
|
delete cur;
|
|
} while (head != nullptr);
|
|
}
|
|
|
|
/// Emit a block literal expression in the current function.
|
|
llvm::Value *CodeGenFunction::EmitBlockLiteral(const BlockExpr *blockExpr) {
|
|
// If the block has no captures, we won't have a pre-computed
|
|
// layout for it.
|
|
if (!blockExpr->getBlockDecl()->hasCaptures()) {
|
|
CGBlockInfo blockInfo(blockExpr->getBlockDecl(), CurFn->getName());
|
|
computeBlockInfo(CGM, this, blockInfo);
|
|
blockInfo.BlockExpression = blockExpr;
|
|
return EmitBlockLiteral(blockInfo);
|
|
}
|
|
|
|
// Find the block info for this block and take ownership of it.
|
|
std::unique_ptr<CGBlockInfo> blockInfo;
|
|
blockInfo.reset(findAndRemoveBlockInfo(&FirstBlockInfo,
|
|
blockExpr->getBlockDecl()));
|
|
|
|
blockInfo->BlockExpression = blockExpr;
|
|
return EmitBlockLiteral(*blockInfo);
|
|
}
|
|
|
|
llvm::Value *CodeGenFunction::EmitBlockLiteral(const CGBlockInfo &blockInfo) {
|
|
// Using the computed layout, generate the actual block function.
|
|
bool isLambdaConv = blockInfo.getBlockDecl()->isConversionFromLambda();
|
|
llvm::Constant *blockFn
|
|
= CodeGenFunction(CGM, true).GenerateBlockFunction(CurGD, blockInfo,
|
|
LocalDeclMap,
|
|
isLambdaConv);
|
|
blockFn = llvm::ConstantExpr::getBitCast(blockFn, VoidPtrTy);
|
|
|
|
// If there is nothing to capture, we can emit this as a global block.
|
|
if (blockInfo.CanBeGlobal)
|
|
return buildGlobalBlock(CGM, blockInfo, blockFn);
|
|
|
|
// Otherwise, we have to emit this as a local block.
|
|
|
|
llvm::Constant *isa = CGM.getNSConcreteStackBlock();
|
|
isa = llvm::ConstantExpr::getBitCast(isa, VoidPtrTy);
|
|
|
|
// Build the block descriptor.
|
|
llvm::Constant *descriptor = buildBlockDescriptor(CGM, blockInfo);
|
|
|
|
Address blockAddr = blockInfo.LocalAddress;
|
|
assert(blockAddr.isValid() && "block has no address!");
|
|
|
|
// Compute the initial on-stack block flags.
|
|
BlockFlags flags = BLOCK_HAS_SIGNATURE;
|
|
if (blockInfo.HasCapturedVariableLayout) flags |= BLOCK_HAS_EXTENDED_LAYOUT;
|
|
if (blockInfo.NeedsCopyDispose) flags |= BLOCK_HAS_COPY_DISPOSE;
|
|
if (blockInfo.HasCXXObject) flags |= BLOCK_HAS_CXX_OBJ;
|
|
if (blockInfo.UsesStret) flags |= BLOCK_USE_STRET;
|
|
|
|
auto projectField =
|
|
[&](unsigned index, CharUnits offset, const Twine &name) -> Address {
|
|
return Builder.CreateStructGEP(blockAddr, index, offset, name);
|
|
};
|
|
auto storeField =
|
|
[&](llvm::Value *value, unsigned index, CharUnits offset,
|
|
const Twine &name) {
|
|
Builder.CreateStore(value, projectField(index, offset, name));
|
|
};
|
|
|
|
// Initialize the block header.
|
|
{
|
|
// We assume all the header fields are densely packed.
|
|
unsigned index = 0;
|
|
CharUnits offset;
|
|
auto addHeaderField =
|
|
[&](llvm::Value *value, CharUnits size, const Twine &name) {
|
|
storeField(value, index, offset, name);
|
|
offset += size;
|
|
index++;
|
|
};
|
|
|
|
addHeaderField(isa, getPointerSize(), "block.isa");
|
|
addHeaderField(llvm::ConstantInt::get(IntTy, flags.getBitMask()),
|
|
getIntSize(), "block.flags");
|
|
addHeaderField(llvm::ConstantInt::get(IntTy, 0),
|
|
getIntSize(), "block.reserved");
|
|
addHeaderField(blockFn, getPointerSize(), "block.invoke");
|
|
addHeaderField(descriptor, getPointerSize(), "block.descriptor");
|
|
}
|
|
|
|
// Finally, capture all the values into the block.
|
|
const BlockDecl *blockDecl = blockInfo.getBlockDecl();
|
|
|
|
// First, 'this'.
|
|
if (blockDecl->capturesCXXThis()) {
|
|
Address addr = projectField(blockInfo.CXXThisIndex, blockInfo.CXXThisOffset,
|
|
"block.captured-this.addr");
|
|
Builder.CreateStore(LoadCXXThis(), addr);
|
|
}
|
|
|
|
// Next, captured variables.
|
|
for (const auto &CI : blockDecl->captures()) {
|
|
const VarDecl *variable = CI.getVariable();
|
|
const CGBlockInfo::Capture &capture = blockInfo.getCapture(variable);
|
|
|
|
// Ignore constant captures.
|
|
if (capture.isConstant()) continue;
|
|
|
|
QualType type = variable->getType();
|
|
|
|
// This will be a [[type]]*, except that a byref entry will just be
|
|
// an i8**.
|
|
Address blockField =
|
|
projectField(capture.getIndex(), capture.getOffset(), "block.captured");
|
|
|
|
// Compute the address of the thing we're going to move into the
|
|
// block literal.
|
|
Address src = Address::invalid();
|
|
|
|
if (blockDecl->isConversionFromLambda()) {
|
|
// The lambda capture in a lambda's conversion-to-block-pointer is
|
|
// special; we'll simply emit it directly.
|
|
src = Address::invalid();
|
|
} else if (CI.isByRef()) {
|
|
if (BlockInfo && CI.isNested()) {
|
|
// We need to use the capture from the enclosing block.
|
|
const CGBlockInfo::Capture &enclosingCapture =
|
|
BlockInfo->getCapture(variable);
|
|
|
|
// This is a [[type]]*, except that a byref entry wil just be an i8**.
|
|
src = Builder.CreateStructGEP(LoadBlockStruct(),
|
|
enclosingCapture.getIndex(),
|
|
enclosingCapture.getOffset(),
|
|
"block.capture.addr");
|
|
} else {
|
|
auto I = LocalDeclMap.find(variable);
|
|
assert(I != LocalDeclMap.end());
|
|
src = I->second;
|
|
}
|
|
} else {
|
|
DeclRefExpr declRef(const_cast<VarDecl *>(variable),
|
|
/*RefersToEnclosingVariableOrCapture*/ CI.isNested(),
|
|
type.getNonReferenceType(), VK_LValue,
|
|
SourceLocation());
|
|
src = EmitDeclRefLValue(&declRef).getAddress();
|
|
};
|
|
|
|
// For byrefs, we just write the pointer to the byref struct into
|
|
// the block field. There's no need to chase the forwarding
|
|
// pointer at this point, since we're building something that will
|
|
// live a shorter life than the stack byref anyway.
|
|
if (CI.isByRef()) {
|
|
// Get a void* that points to the byref struct.
|
|
llvm::Value *byrefPointer;
|
|
if (CI.isNested())
|
|
byrefPointer = Builder.CreateLoad(src, "byref.capture");
|
|
else
|
|
byrefPointer = Builder.CreateBitCast(src.getPointer(), VoidPtrTy);
|
|
|
|
// Write that void* into the capture field.
|
|
Builder.CreateStore(byrefPointer, blockField);
|
|
|
|
// If we have a copy constructor, evaluate that into the block field.
|
|
} else if (const Expr *copyExpr = CI.getCopyExpr()) {
|
|
if (blockDecl->isConversionFromLambda()) {
|
|
// If we have a lambda conversion, emit the expression
|
|
// directly into the block instead.
|
|
AggValueSlot Slot =
|
|
AggValueSlot::forAddr(blockField, Qualifiers(),
|
|
AggValueSlot::IsDestructed,
|
|
AggValueSlot::DoesNotNeedGCBarriers,
|
|
AggValueSlot::IsNotAliased);
|
|
EmitAggExpr(copyExpr, Slot);
|
|
} else {
|
|
EmitSynthesizedCXXCopyCtor(blockField, src, copyExpr);
|
|
}
|
|
|
|
// If it's a reference variable, copy the reference into the block field.
|
|
} else if (type->isReferenceType()) {
|
|
Builder.CreateStore(src.getPointer(), blockField);
|
|
|
|
// If this is an ARC __strong block-pointer variable, don't do a
|
|
// block copy.
|
|
//
|
|
// TODO: this can be generalized into the normal initialization logic:
|
|
// we should never need to do a block-copy when initializing a local
|
|
// variable, because the local variable's lifetime should be strictly
|
|
// contained within the stack block's.
|
|
} else if (type.getObjCLifetime() == Qualifiers::OCL_Strong &&
|
|
type->isBlockPointerType()) {
|
|
// Load the block and do a simple retain.
|
|
llvm::Value *value = Builder.CreateLoad(src, "block.captured_block");
|
|
value = EmitARCRetainNonBlock(value);
|
|
|
|
// Do a primitive store to the block field.
|
|
Builder.CreateStore(value, blockField);
|
|
|
|
// Otherwise, fake up a POD copy into the block field.
|
|
} else {
|
|
// Fake up a new variable so that EmitScalarInit doesn't think
|
|
// we're referring to the variable in its own initializer.
|
|
ImplicitParamDecl blockFieldPseudoVar(getContext(), /*DC*/ nullptr,
|
|
SourceLocation(), /*name*/ nullptr,
|
|
type);
|
|
|
|
// We use one of these or the other depending on whether the
|
|
// reference is nested.
|
|
DeclRefExpr declRef(const_cast<VarDecl *>(variable),
|
|
/*RefersToEnclosingVariableOrCapture*/ CI.isNested(),
|
|
type, VK_LValue, SourceLocation());
|
|
|
|
ImplicitCastExpr l2r(ImplicitCastExpr::OnStack, type, CK_LValueToRValue,
|
|
&declRef, VK_RValue);
|
|
// FIXME: Pass a specific location for the expr init so that the store is
|
|
// attributed to a reasonable location - otherwise it may be attributed to
|
|
// locations of subexpressions in the initialization.
|
|
EmitExprAsInit(&l2r, &blockFieldPseudoVar,
|
|
MakeAddrLValue(blockField, type, AlignmentSource::Decl),
|
|
/*captured by init*/ false);
|
|
}
|
|
|
|
// Activate the cleanup if layout pushed one.
|
|
if (!CI.isByRef()) {
|
|
EHScopeStack::stable_iterator cleanup = capture.getCleanup();
|
|
if (cleanup.isValid())
|
|
ActivateCleanupBlock(cleanup, blockInfo.DominatingIP);
|
|
}
|
|
}
|
|
|
|
// Cast to the converted block-pointer type, which happens (somewhat
|
|
// unfortunately) to be a pointer to function type.
|
|
llvm::Value *result =
|
|
Builder.CreateBitCast(blockAddr.getPointer(),
|
|
ConvertType(blockInfo.getBlockExpr()->getType()));
|
|
|
|
return result;
|
|
}
|
|
|
|
|
|
llvm::Type *CodeGenModule::getBlockDescriptorType() {
|
|
if (BlockDescriptorType)
|
|
return BlockDescriptorType;
|
|
|
|
llvm::Type *UnsignedLongTy =
|
|
getTypes().ConvertType(getContext().UnsignedLongTy);
|
|
|
|
// struct __block_descriptor {
|
|
// unsigned long reserved;
|
|
// unsigned long block_size;
|
|
//
|
|
// // later, the following will be added
|
|
//
|
|
// struct {
|
|
// void (*copyHelper)();
|
|
// void (*copyHelper)();
|
|
// } helpers; // !!! optional
|
|
//
|
|
// const char *signature; // the block signature
|
|
// const char *layout; // reserved
|
|
// };
|
|
BlockDescriptorType =
|
|
llvm::StructType::create("struct.__block_descriptor",
|
|
UnsignedLongTy, UnsignedLongTy, nullptr);
|
|
|
|
// Now form a pointer to that.
|
|
BlockDescriptorType = llvm::PointerType::getUnqual(BlockDescriptorType);
|
|
return BlockDescriptorType;
|
|
}
|
|
|
|
llvm::Type *CodeGenModule::getGenericBlockLiteralType() {
|
|
if (GenericBlockLiteralType)
|
|
return GenericBlockLiteralType;
|
|
|
|
llvm::Type *BlockDescPtrTy = getBlockDescriptorType();
|
|
|
|
// struct __block_literal_generic {
|
|
// void *__isa;
|
|
// int __flags;
|
|
// int __reserved;
|
|
// void (*__invoke)(void *);
|
|
// struct __block_descriptor *__descriptor;
|
|
// };
|
|
GenericBlockLiteralType =
|
|
llvm::StructType::create("struct.__block_literal_generic",
|
|
VoidPtrTy, IntTy, IntTy, VoidPtrTy,
|
|
BlockDescPtrTy, nullptr);
|
|
|
|
return GenericBlockLiteralType;
|
|
}
|
|
|
|
RValue CodeGenFunction::EmitBlockCallExpr(const CallExpr *E,
|
|
ReturnValueSlot ReturnValue) {
|
|
const BlockPointerType *BPT =
|
|
E->getCallee()->getType()->getAs<BlockPointerType>();
|
|
|
|
llvm::Value *Callee = EmitScalarExpr(E->getCallee());
|
|
|
|
// Get a pointer to the generic block literal.
|
|
llvm::Type *BlockLiteralTy =
|
|
llvm::PointerType::getUnqual(CGM.getGenericBlockLiteralType());
|
|
|
|
// Bitcast the callee to a block literal.
|
|
llvm::Value *BlockLiteral =
|
|
Builder.CreateBitCast(Callee, BlockLiteralTy, "block.literal");
|
|
|
|
// Get the function pointer from the literal.
|
|
llvm::Value *FuncPtr =
|
|
Builder.CreateStructGEP(CGM.getGenericBlockLiteralType(), BlockLiteral, 3);
|
|
|
|
BlockLiteral = Builder.CreateBitCast(BlockLiteral, VoidPtrTy);
|
|
|
|
// Add the block literal.
|
|
CallArgList Args;
|
|
Args.add(RValue::get(BlockLiteral), getContext().VoidPtrTy);
|
|
|
|
QualType FnType = BPT->getPointeeType();
|
|
|
|
// And the rest of the arguments.
|
|
EmitCallArgs(Args, FnType->getAs<FunctionProtoType>(), E->arguments());
|
|
|
|
// Load the function.
|
|
llvm::Value *Func = Builder.CreateAlignedLoad(FuncPtr, getPointerAlign());
|
|
|
|
const FunctionType *FuncTy = FnType->castAs<FunctionType>();
|
|
const CGFunctionInfo &FnInfo =
|
|
CGM.getTypes().arrangeBlockFunctionCall(Args, FuncTy);
|
|
|
|
// Cast the function pointer to the right type.
|
|
llvm::Type *BlockFTy = CGM.getTypes().GetFunctionType(FnInfo);
|
|
|
|
llvm::Type *BlockFTyPtr = llvm::PointerType::getUnqual(BlockFTy);
|
|
Func = Builder.CreateBitCast(Func, BlockFTyPtr);
|
|
|
|
// And call the block.
|
|
return EmitCall(FnInfo, Func, ReturnValue, Args);
|
|
}
|
|
|
|
Address CodeGenFunction::GetAddrOfBlockDecl(const VarDecl *variable,
|
|
bool isByRef) {
|
|
assert(BlockInfo && "evaluating block ref without block information?");
|
|
const CGBlockInfo::Capture &capture = BlockInfo->getCapture(variable);
|
|
|
|
// Handle constant captures.
|
|
if (capture.isConstant()) return LocalDeclMap.find(variable)->second;
|
|
|
|
Address addr =
|
|
Builder.CreateStructGEP(LoadBlockStruct(), capture.getIndex(),
|
|
capture.getOffset(), "block.capture.addr");
|
|
|
|
if (isByRef) {
|
|
// addr should be a void** right now. Load, then cast the result
|
|
// to byref*.
|
|
|
|
auto &byrefInfo = getBlockByrefInfo(variable);
|
|
addr = Address(Builder.CreateLoad(addr), byrefInfo.ByrefAlignment);
|
|
|
|
auto byrefPointerType = llvm::PointerType::get(byrefInfo.Type, 0);
|
|
addr = Builder.CreateBitCast(addr, byrefPointerType, "byref.addr");
|
|
|
|
addr = emitBlockByrefAddress(addr, byrefInfo, /*follow*/ true,
|
|
variable->getName());
|
|
}
|
|
|
|
if (auto refType = variable->getType()->getAs<ReferenceType>()) {
|
|
addr = EmitLoadOfReference(addr, refType);
|
|
}
|
|
|
|
return addr;
|
|
}
|
|
|
|
llvm::Constant *
|
|
CodeGenModule::GetAddrOfGlobalBlock(const BlockExpr *blockExpr,
|
|
const char *name) {
|
|
CGBlockInfo blockInfo(blockExpr->getBlockDecl(), name);
|
|
blockInfo.BlockExpression = blockExpr;
|
|
|
|
// Compute information about the layout, etc., of this block.
|
|
computeBlockInfo(*this, nullptr, blockInfo);
|
|
|
|
// Using that metadata, generate the actual block function.
|
|
llvm::Constant *blockFn;
|
|
{
|
|
CodeGenFunction::DeclMapTy LocalDeclMap;
|
|
blockFn = CodeGenFunction(*this).GenerateBlockFunction(GlobalDecl(),
|
|
blockInfo,
|
|
LocalDeclMap,
|
|
false);
|
|
}
|
|
blockFn = llvm::ConstantExpr::getBitCast(blockFn, VoidPtrTy);
|
|
|
|
return buildGlobalBlock(*this, blockInfo, blockFn);
|
|
}
|
|
|
|
static llvm::Constant *buildGlobalBlock(CodeGenModule &CGM,
|
|
const CGBlockInfo &blockInfo,
|
|
llvm::Constant *blockFn) {
|
|
assert(blockInfo.CanBeGlobal);
|
|
|
|
// Generate the constants for the block literal initializer.
|
|
llvm::Constant *fields[BlockHeaderSize];
|
|
|
|
// isa
|
|
fields[0] = CGM.getNSConcreteGlobalBlock();
|
|
|
|
// __flags
|
|
BlockFlags flags = BLOCK_IS_GLOBAL | BLOCK_HAS_SIGNATURE;
|
|
if (blockInfo.UsesStret) flags |= BLOCK_USE_STRET;
|
|
|
|
fields[1] = llvm::ConstantInt::get(CGM.IntTy, flags.getBitMask());
|
|
|
|
// Reserved
|
|
fields[2] = llvm::Constant::getNullValue(CGM.IntTy);
|
|
|
|
// Function
|
|
fields[3] = blockFn;
|
|
|
|
// Descriptor
|
|
fields[4] = buildBlockDescriptor(CGM, blockInfo);
|
|
|
|
llvm::Constant *init = llvm::ConstantStruct::getAnon(fields);
|
|
|
|
llvm::GlobalVariable *literal =
|
|
new llvm::GlobalVariable(CGM.getModule(),
|
|
init->getType(),
|
|
/*constant*/ true,
|
|
llvm::GlobalVariable::InternalLinkage,
|
|
init,
|
|
"__block_literal_global");
|
|
literal->setAlignment(blockInfo.BlockAlign.getQuantity());
|
|
|
|
// Return a constant of the appropriately-casted type.
|
|
llvm::Type *requiredType =
|
|
CGM.getTypes().ConvertType(blockInfo.getBlockExpr()->getType());
|
|
return llvm::ConstantExpr::getBitCast(literal, requiredType);
|
|
}
|
|
|
|
void CodeGenFunction::setBlockContextParameter(const ImplicitParamDecl *D,
|
|
unsigned argNum,
|
|
llvm::Value *arg) {
|
|
assert(BlockInfo && "not emitting prologue of block invocation function?!");
|
|
|
|
llvm::Value *localAddr = nullptr;
|
|
if (CGM.getCodeGenOpts().OptimizationLevel == 0) {
|
|
// Allocate a stack slot to let the debug info survive the RA.
|
|
Address alloc = CreateMemTemp(D->getType(), D->getName() + ".addr");
|
|
Builder.CreateStore(arg, alloc);
|
|
localAddr = Builder.CreateLoad(alloc);
|
|
}
|
|
|
|
if (CGDebugInfo *DI = getDebugInfo()) {
|
|
if (CGM.getCodeGenOpts().getDebugInfo() >=
|
|
codegenoptions::LimitedDebugInfo) {
|
|
DI->setLocation(D->getLocation());
|
|
DI->EmitDeclareOfBlockLiteralArgVariable(*BlockInfo, arg, argNum,
|
|
localAddr, Builder);
|
|
}
|
|
}
|
|
|
|
SourceLocation StartLoc = BlockInfo->getBlockExpr()->getBody()->getLocStart();
|
|
ApplyDebugLocation Scope(*this, StartLoc);
|
|
|
|
// Instead of messing around with LocalDeclMap, just set the value
|
|
// directly as BlockPointer.
|
|
BlockPointer = Builder.CreateBitCast(arg,
|
|
BlockInfo->StructureType->getPointerTo(),
|
|
"block");
|
|
}
|
|
|
|
Address CodeGenFunction::LoadBlockStruct() {
|
|
assert(BlockInfo && "not in a block invocation function!");
|
|
assert(BlockPointer && "no block pointer set!");
|
|
return Address(BlockPointer, BlockInfo->BlockAlign);
|
|
}
|
|
|
|
llvm::Function *
|
|
CodeGenFunction::GenerateBlockFunction(GlobalDecl GD,
|
|
const CGBlockInfo &blockInfo,
|
|
const DeclMapTy &ldm,
|
|
bool IsLambdaConversionToBlock) {
|
|
const BlockDecl *blockDecl = blockInfo.getBlockDecl();
|
|
|
|
CurGD = GD;
|
|
|
|
CurEHLocation = blockInfo.getBlockExpr()->getLocEnd();
|
|
|
|
BlockInfo = &blockInfo;
|
|
|
|
// Arrange for local static and local extern declarations to appear
|
|
// to be local to this function as well, in case they're directly
|
|
// referenced in a block.
|
|
for (DeclMapTy::const_iterator i = ldm.begin(), e = ldm.end(); i != e; ++i) {
|
|
const auto *var = dyn_cast<VarDecl>(i->first);
|
|
if (var && !var->hasLocalStorage())
|
|
setAddrOfLocalVar(var, i->second);
|
|
}
|
|
|
|
// Begin building the function declaration.
|
|
|
|
// Build the argument list.
|
|
FunctionArgList args;
|
|
|
|
// The first argument is the block pointer. Just take it as a void*
|
|
// and cast it later.
|
|
QualType selfTy = getContext().VoidPtrTy;
|
|
IdentifierInfo *II = &CGM.getContext().Idents.get(".block_descriptor");
|
|
|
|
ImplicitParamDecl selfDecl(getContext(), const_cast<BlockDecl*>(blockDecl),
|
|
SourceLocation(), II, selfTy);
|
|
args.push_back(&selfDecl);
|
|
|
|
// Now add the rest of the parameters.
|
|
args.append(blockDecl->param_begin(), blockDecl->param_end());
|
|
|
|
// Create the function declaration.
|
|
const FunctionProtoType *fnType = blockInfo.getBlockExpr()->getFunctionType();
|
|
const CGFunctionInfo &fnInfo =
|
|
CGM.getTypes().arrangeBlockFunctionDeclaration(fnType, args);
|
|
if (CGM.ReturnSlotInterferesWithArgs(fnInfo))
|
|
blockInfo.UsesStret = true;
|
|
|
|
llvm::FunctionType *fnLLVMType = CGM.getTypes().GetFunctionType(fnInfo);
|
|
|
|
StringRef name = CGM.getBlockMangledName(GD, blockDecl);
|
|
llvm::Function *fn = llvm::Function::Create(
|
|
fnLLVMType, llvm::GlobalValue::InternalLinkage, name, &CGM.getModule());
|
|
CGM.SetInternalFunctionAttributes(blockDecl, fn, fnInfo);
|
|
|
|
// Begin generating the function.
|
|
StartFunction(blockDecl, fnType->getReturnType(), fn, fnInfo, args,
|
|
blockDecl->getLocation(),
|
|
blockInfo.getBlockExpr()->getBody()->getLocStart());
|
|
|
|
// Okay. Undo some of what StartFunction did.
|
|
|
|
// At -O0 we generate an explicit alloca for the BlockPointer, so the RA
|
|
// won't delete the dbg.declare intrinsics for captured variables.
|
|
llvm::Value *BlockPointerDbgLoc = BlockPointer;
|
|
if (CGM.getCodeGenOpts().OptimizationLevel == 0) {
|
|
// Allocate a stack slot for it, so we can point the debugger to it
|
|
Address Alloca = CreateTempAlloca(BlockPointer->getType(),
|
|
getPointerAlign(),
|
|
"block.addr");
|
|
// Set the DebugLocation to empty, so the store is recognized as a
|
|
// frame setup instruction by llvm::DwarfDebug::beginFunction().
|
|
auto NL = ApplyDebugLocation::CreateEmpty(*this);
|
|
Builder.CreateStore(BlockPointer, Alloca);
|
|
BlockPointerDbgLoc = Alloca.getPointer();
|
|
}
|
|
|
|
// If we have a C++ 'this' reference, go ahead and force it into
|
|
// existence now.
|
|
if (blockDecl->capturesCXXThis()) {
|
|
Address addr =
|
|
Builder.CreateStructGEP(LoadBlockStruct(), blockInfo.CXXThisIndex,
|
|
blockInfo.CXXThisOffset, "block.captured-this");
|
|
CXXThisValue = Builder.CreateLoad(addr, "this");
|
|
}
|
|
|
|
// Also force all the constant captures.
|
|
for (const auto &CI : blockDecl->captures()) {
|
|
const VarDecl *variable = CI.getVariable();
|
|
const CGBlockInfo::Capture &capture = blockInfo.getCapture(variable);
|
|
if (!capture.isConstant()) continue;
|
|
|
|
CharUnits align = getContext().getDeclAlign(variable);
|
|
Address alloca =
|
|
CreateMemTemp(variable->getType(), align, "block.captured-const");
|
|
|
|
Builder.CreateStore(capture.getConstant(), alloca);
|
|
|
|
setAddrOfLocalVar(variable, alloca);
|
|
}
|
|
|
|
// Save a spot to insert the debug information for all the DeclRefExprs.
|
|
llvm::BasicBlock *entry = Builder.GetInsertBlock();
|
|
llvm::BasicBlock::iterator entry_ptr = Builder.GetInsertPoint();
|
|
--entry_ptr;
|
|
|
|
if (IsLambdaConversionToBlock)
|
|
EmitLambdaBlockInvokeBody();
|
|
else {
|
|
PGO.assignRegionCounters(GlobalDecl(blockDecl), fn);
|
|
incrementProfileCounter(blockDecl->getBody());
|
|
EmitStmt(blockDecl->getBody());
|
|
}
|
|
|
|
// Remember where we were...
|
|
llvm::BasicBlock *resume = Builder.GetInsertBlock();
|
|
|
|
// Go back to the entry.
|
|
++entry_ptr;
|
|
Builder.SetInsertPoint(entry, entry_ptr);
|
|
|
|
// Emit debug information for all the DeclRefExprs.
|
|
// FIXME: also for 'this'
|
|
if (CGDebugInfo *DI = getDebugInfo()) {
|
|
for (const auto &CI : blockDecl->captures()) {
|
|
const VarDecl *variable = CI.getVariable();
|
|
DI->EmitLocation(Builder, variable->getLocation());
|
|
|
|
if (CGM.getCodeGenOpts().getDebugInfo() >=
|
|
codegenoptions::LimitedDebugInfo) {
|
|
const CGBlockInfo::Capture &capture = blockInfo.getCapture(variable);
|
|
if (capture.isConstant()) {
|
|
auto addr = LocalDeclMap.find(variable)->second;
|
|
DI->EmitDeclareOfAutoVariable(variable, addr.getPointer(),
|
|
Builder);
|
|
continue;
|
|
}
|
|
|
|
DI->EmitDeclareOfBlockDeclRefVariable(
|
|
variable, BlockPointerDbgLoc, Builder, blockInfo,
|
|
entry_ptr == entry->end() ? nullptr : &*entry_ptr);
|
|
}
|
|
}
|
|
// Recover location if it was changed in the above loop.
|
|
DI->EmitLocation(Builder,
|
|
cast<CompoundStmt>(blockDecl->getBody())->getRBracLoc());
|
|
}
|
|
|
|
// And resume where we left off.
|
|
if (resume == nullptr)
|
|
Builder.ClearInsertionPoint();
|
|
else
|
|
Builder.SetInsertPoint(resume);
|
|
|
|
FinishFunction(cast<CompoundStmt>(blockDecl->getBody())->getRBracLoc());
|
|
|
|
return fn;
|
|
}
|
|
|
|
/*
|
|
notes.push_back(HelperInfo());
|
|
HelperInfo ¬e = notes.back();
|
|
note.index = capture.getIndex();
|
|
note.RequiresCopying = (ci->hasCopyExpr() || BlockRequiresCopying(type));
|
|
note.cxxbar_import = ci->getCopyExpr();
|
|
|
|
if (ci->isByRef()) {
|
|
note.flag = BLOCK_FIELD_IS_BYREF;
|
|
if (type.isObjCGCWeak())
|
|
note.flag |= BLOCK_FIELD_IS_WEAK;
|
|
} else if (type->isBlockPointerType()) {
|
|
note.flag = BLOCK_FIELD_IS_BLOCK;
|
|
} else {
|
|
note.flag = BLOCK_FIELD_IS_OBJECT;
|
|
}
|
|
*/
|
|
|
|
/// Generate the copy-helper function for a block closure object:
|
|
/// static void block_copy_helper(block_t *dst, block_t *src);
|
|
/// The runtime will have previously initialized 'dst' by doing a
|
|
/// bit-copy of 'src'.
|
|
///
|
|
/// Note that this copies an entire block closure object to the heap;
|
|
/// it should not be confused with a 'byref copy helper', which moves
|
|
/// the contents of an individual __block variable to the heap.
|
|
llvm::Constant *
|
|
CodeGenFunction::GenerateCopyHelperFunction(const CGBlockInfo &blockInfo) {
|
|
ASTContext &C = getContext();
|
|
|
|
FunctionArgList args;
|
|
ImplicitParamDecl dstDecl(getContext(), nullptr, SourceLocation(), nullptr,
|
|
C.VoidPtrTy);
|
|
args.push_back(&dstDecl);
|
|
ImplicitParamDecl srcDecl(getContext(), nullptr, SourceLocation(), nullptr,
|
|
C.VoidPtrTy);
|
|
args.push_back(&srcDecl);
|
|
|
|
const CGFunctionInfo &FI =
|
|
CGM.getTypes().arrangeBuiltinFunctionDeclaration(C.VoidTy, args);
|
|
|
|
// FIXME: it would be nice if these were mergeable with things with
|
|
// identical semantics.
|
|
llvm::FunctionType *LTy = CGM.getTypes().GetFunctionType(FI);
|
|
|
|
llvm::Function *Fn =
|
|
llvm::Function::Create(LTy, llvm::GlobalValue::InternalLinkage,
|
|
"__copy_helper_block_", &CGM.getModule());
|
|
|
|
IdentifierInfo *II
|
|
= &CGM.getContext().Idents.get("__copy_helper_block_");
|
|
|
|
FunctionDecl *FD = FunctionDecl::Create(C,
|
|
C.getTranslationUnitDecl(),
|
|
SourceLocation(),
|
|
SourceLocation(), II, C.VoidTy,
|
|
nullptr, SC_Static,
|
|
false,
|
|
false);
|
|
|
|
CGM.SetInternalFunctionAttributes(nullptr, Fn, FI);
|
|
|
|
auto NL = ApplyDebugLocation::CreateEmpty(*this);
|
|
StartFunction(FD, C.VoidTy, Fn, FI, args);
|
|
// Create a scope with an artificial location for the body of this function.
|
|
auto AL = ApplyDebugLocation::CreateArtificial(*this);
|
|
llvm::Type *structPtrTy = blockInfo.StructureType->getPointerTo();
|
|
|
|
Address src = GetAddrOfLocalVar(&srcDecl);
|
|
src = Address(Builder.CreateLoad(src), blockInfo.BlockAlign);
|
|
src = Builder.CreateBitCast(src, structPtrTy, "block.source");
|
|
|
|
Address dst = GetAddrOfLocalVar(&dstDecl);
|
|
dst = Address(Builder.CreateLoad(dst), blockInfo.BlockAlign);
|
|
dst = Builder.CreateBitCast(dst, structPtrTy, "block.dest");
|
|
|
|
const BlockDecl *blockDecl = blockInfo.getBlockDecl();
|
|
|
|
for (const auto &CI : blockDecl->captures()) {
|
|
const VarDecl *variable = CI.getVariable();
|
|
QualType type = variable->getType();
|
|
|
|
const CGBlockInfo::Capture &capture = blockInfo.getCapture(variable);
|
|
if (capture.isConstant()) continue;
|
|
|
|
const Expr *copyExpr = CI.getCopyExpr();
|
|
BlockFieldFlags flags;
|
|
|
|
bool useARCWeakCopy = false;
|
|
bool useARCStrongCopy = false;
|
|
|
|
if (copyExpr) {
|
|
assert(!CI.isByRef());
|
|
// don't bother computing flags
|
|
|
|
} else if (CI.isByRef()) {
|
|
flags = BLOCK_FIELD_IS_BYREF;
|
|
if (type.isObjCGCWeak())
|
|
flags |= BLOCK_FIELD_IS_WEAK;
|
|
|
|
} else if (type->isObjCRetainableType()) {
|
|
flags = BLOCK_FIELD_IS_OBJECT;
|
|
bool isBlockPointer = type->isBlockPointerType();
|
|
if (isBlockPointer)
|
|
flags = BLOCK_FIELD_IS_BLOCK;
|
|
|
|
// Special rules for ARC captures:
|
|
Qualifiers qs = type.getQualifiers();
|
|
|
|
// We need to register __weak direct captures with the runtime.
|
|
if (qs.getObjCLifetime() == Qualifiers::OCL_Weak) {
|
|
useARCWeakCopy = true;
|
|
|
|
// We need to retain the copied value for __strong direct captures.
|
|
} else if (qs.getObjCLifetime() == Qualifiers::OCL_Strong) {
|
|
// If it's a block pointer, we have to copy the block and
|
|
// assign that to the destination pointer, so we might as
|
|
// well use _Block_object_assign. Otherwise we can avoid that.
|
|
if (!isBlockPointer)
|
|
useARCStrongCopy = true;
|
|
|
|
// Non-ARC captures of retainable pointers are strong and
|
|
// therefore require a call to _Block_object_assign.
|
|
} else if (!qs.getObjCLifetime() && !getLangOpts().ObjCAutoRefCount) {
|
|
// fall through
|
|
|
|
// Otherwise the memcpy is fine.
|
|
} else {
|
|
continue;
|
|
}
|
|
|
|
// For all other types, the memcpy is fine.
|
|
} else {
|
|
continue;
|
|
}
|
|
|
|
unsigned index = capture.getIndex();
|
|
Address srcField = Builder.CreateStructGEP(src, index, capture.getOffset());
|
|
Address dstField = Builder.CreateStructGEP(dst, index, capture.getOffset());
|
|
|
|
// If there's an explicit copy expression, we do that.
|
|
if (copyExpr) {
|
|
EmitSynthesizedCXXCopyCtor(dstField, srcField, copyExpr);
|
|
} else if (useARCWeakCopy) {
|
|
EmitARCCopyWeak(dstField, srcField);
|
|
} else {
|
|
llvm::Value *srcValue = Builder.CreateLoad(srcField, "blockcopy.src");
|
|
if (useARCStrongCopy) {
|
|
// At -O0, store null into the destination field (so that the
|
|
// storeStrong doesn't over-release) and then call storeStrong.
|
|
// This is a workaround to not having an initStrong call.
|
|
if (CGM.getCodeGenOpts().OptimizationLevel == 0) {
|
|
auto *ty = cast<llvm::PointerType>(srcValue->getType());
|
|
llvm::Value *null = llvm::ConstantPointerNull::get(ty);
|
|
Builder.CreateStore(null, dstField);
|
|
EmitARCStoreStrongCall(dstField, srcValue, true);
|
|
|
|
// With optimization enabled, take advantage of the fact that
|
|
// the blocks runtime guarantees a memcpy of the block data, and
|
|
// just emit a retain of the src field.
|
|
} else {
|
|
EmitARCRetainNonBlock(srcValue);
|
|
|
|
// We don't need this anymore, so kill it. It's not quite
|
|
// worth the annoyance to avoid creating it in the first place.
|
|
cast<llvm::Instruction>(dstField.getPointer())->eraseFromParent();
|
|
}
|
|
} else {
|
|
srcValue = Builder.CreateBitCast(srcValue, VoidPtrTy);
|
|
llvm::Value *dstAddr =
|
|
Builder.CreateBitCast(dstField.getPointer(), VoidPtrTy);
|
|
llvm::Value *args[] = {
|
|
dstAddr, srcValue, llvm::ConstantInt::get(Int32Ty, flags.getBitMask())
|
|
};
|
|
|
|
bool copyCanThrow = false;
|
|
if (CI.isByRef() && variable->getType()->getAsCXXRecordDecl()) {
|
|
const Expr *copyExpr =
|
|
CGM.getContext().getBlockVarCopyInits(variable);
|
|
if (copyExpr) {
|
|
copyCanThrow = true; // FIXME: reuse the noexcept logic
|
|
}
|
|
}
|
|
|
|
if (copyCanThrow) {
|
|
EmitRuntimeCallOrInvoke(CGM.getBlockObjectAssign(), args);
|
|
} else {
|
|
EmitNounwindRuntimeCall(CGM.getBlockObjectAssign(), args);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
FinishFunction();
|
|
|
|
return llvm::ConstantExpr::getBitCast(Fn, VoidPtrTy);
|
|
}
|
|
|
|
/// Generate the destroy-helper function for a block closure object:
|
|
/// static void block_destroy_helper(block_t *theBlock);
|
|
///
|
|
/// Note that this destroys a heap-allocated block closure object;
|
|
/// it should not be confused with a 'byref destroy helper', which
|
|
/// destroys the heap-allocated contents of an individual __block
|
|
/// variable.
|
|
llvm::Constant *
|
|
CodeGenFunction::GenerateDestroyHelperFunction(const CGBlockInfo &blockInfo) {
|
|
ASTContext &C = getContext();
|
|
|
|
FunctionArgList args;
|
|
ImplicitParamDecl srcDecl(getContext(), nullptr, SourceLocation(), nullptr,
|
|
C.VoidPtrTy);
|
|
args.push_back(&srcDecl);
|
|
|
|
const CGFunctionInfo &FI =
|
|
CGM.getTypes().arrangeBuiltinFunctionDeclaration(C.VoidTy, args);
|
|
|
|
// FIXME: We'd like to put these into a mergable by content, with
|
|
// internal linkage.
|
|
llvm::FunctionType *LTy = CGM.getTypes().GetFunctionType(FI);
|
|
|
|
llvm::Function *Fn =
|
|
llvm::Function::Create(LTy, llvm::GlobalValue::InternalLinkage,
|
|
"__destroy_helper_block_", &CGM.getModule());
|
|
|
|
IdentifierInfo *II
|
|
= &CGM.getContext().Idents.get("__destroy_helper_block_");
|
|
|
|
FunctionDecl *FD = FunctionDecl::Create(C, C.getTranslationUnitDecl(),
|
|
SourceLocation(),
|
|
SourceLocation(), II, C.VoidTy,
|
|
nullptr, SC_Static,
|
|
false, false);
|
|
|
|
CGM.SetInternalFunctionAttributes(nullptr, Fn, FI);
|
|
|
|
// Create a scope with an artificial location for the body of this function.
|
|
auto NL = ApplyDebugLocation::CreateEmpty(*this);
|
|
StartFunction(FD, C.VoidTy, Fn, FI, args);
|
|
auto AL = ApplyDebugLocation::CreateArtificial(*this);
|
|
|
|
llvm::Type *structPtrTy = blockInfo.StructureType->getPointerTo();
|
|
|
|
Address src = GetAddrOfLocalVar(&srcDecl);
|
|
src = Address(Builder.CreateLoad(src), blockInfo.BlockAlign);
|
|
src = Builder.CreateBitCast(src, structPtrTy, "block");
|
|
|
|
const BlockDecl *blockDecl = blockInfo.getBlockDecl();
|
|
|
|
CodeGenFunction::RunCleanupsScope cleanups(*this);
|
|
|
|
for (const auto &CI : blockDecl->captures()) {
|
|
const VarDecl *variable = CI.getVariable();
|
|
QualType type = variable->getType();
|
|
|
|
const CGBlockInfo::Capture &capture = blockInfo.getCapture(variable);
|
|
if (capture.isConstant()) continue;
|
|
|
|
BlockFieldFlags flags;
|
|
const CXXDestructorDecl *dtor = nullptr;
|
|
|
|
bool useARCWeakDestroy = false;
|
|
bool useARCStrongDestroy = false;
|
|
|
|
if (CI.isByRef()) {
|
|
flags = BLOCK_FIELD_IS_BYREF;
|
|
if (type.isObjCGCWeak())
|
|
flags |= BLOCK_FIELD_IS_WEAK;
|
|
} else if (const CXXRecordDecl *record = type->getAsCXXRecordDecl()) {
|
|
if (record->hasTrivialDestructor())
|
|
continue;
|
|
dtor = record->getDestructor();
|
|
} else if (type->isObjCRetainableType()) {
|
|
flags = BLOCK_FIELD_IS_OBJECT;
|
|
if (type->isBlockPointerType())
|
|
flags = BLOCK_FIELD_IS_BLOCK;
|
|
|
|
// Special rules for ARC captures.
|
|
Qualifiers qs = type.getQualifiers();
|
|
|
|
// Use objc_storeStrong for __strong direct captures; the
|
|
// dynamic tools really like it when we do this.
|
|
if (qs.getObjCLifetime() == Qualifiers::OCL_Strong) {
|
|
useARCStrongDestroy = true;
|
|
|
|
// Support __weak direct captures.
|
|
} else if (qs.getObjCLifetime() == Qualifiers::OCL_Weak) {
|
|
useARCWeakDestroy = true;
|
|
|
|
// Non-ARC captures are strong, and we need to use _Block_object_dispose.
|
|
} else if (!qs.hasObjCLifetime() && !getLangOpts().ObjCAutoRefCount) {
|
|
// fall through
|
|
|
|
// Otherwise, we have nothing to do.
|
|
} else {
|
|
continue;
|
|
}
|
|
} else {
|
|
continue;
|
|
}
|
|
|
|
Address srcField =
|
|
Builder.CreateStructGEP(src, capture.getIndex(), capture.getOffset());
|
|
|
|
// If there's an explicit copy expression, we do that.
|
|
if (dtor) {
|
|
PushDestructorCleanup(dtor, srcField);
|
|
|
|
// If this is a __weak capture, emit the release directly.
|
|
} else if (useARCWeakDestroy) {
|
|
EmitARCDestroyWeak(srcField);
|
|
|
|
// Destroy strong objects with a call if requested.
|
|
} else if (useARCStrongDestroy) {
|
|
EmitARCDestroyStrong(srcField, ARCImpreciseLifetime);
|
|
|
|
// Otherwise we call _Block_object_dispose. It wouldn't be too
|
|
// hard to just emit this as a cleanup if we wanted to make sure
|
|
// that things were done in reverse.
|
|
} else {
|
|
llvm::Value *value = Builder.CreateLoad(srcField);
|
|
value = Builder.CreateBitCast(value, VoidPtrTy);
|
|
BuildBlockRelease(value, flags);
|
|
}
|
|
}
|
|
|
|
cleanups.ForceCleanup();
|
|
|
|
FinishFunction();
|
|
|
|
return llvm::ConstantExpr::getBitCast(Fn, VoidPtrTy);
|
|
}
|
|
|
|
namespace {
|
|
|
|
/// Emits the copy/dispose helper functions for a __block object of id type.
|
|
class ObjectByrefHelpers final : public BlockByrefHelpers {
|
|
BlockFieldFlags Flags;
|
|
|
|
public:
|
|
ObjectByrefHelpers(CharUnits alignment, BlockFieldFlags flags)
|
|
: BlockByrefHelpers(alignment), Flags(flags) {}
|
|
|
|
void emitCopy(CodeGenFunction &CGF, Address destField,
|
|
Address srcField) override {
|
|
destField = CGF.Builder.CreateBitCast(destField, CGF.VoidPtrTy);
|
|
|
|
srcField = CGF.Builder.CreateBitCast(srcField, CGF.VoidPtrPtrTy);
|
|
llvm::Value *srcValue = CGF.Builder.CreateLoad(srcField);
|
|
|
|
unsigned flags = (Flags | BLOCK_BYREF_CALLER).getBitMask();
|
|
|
|
llvm::Value *flagsVal = llvm::ConstantInt::get(CGF.Int32Ty, flags);
|
|
llvm::Value *fn = CGF.CGM.getBlockObjectAssign();
|
|
|
|
llvm::Value *args[] = { destField.getPointer(), srcValue, flagsVal };
|
|
CGF.EmitNounwindRuntimeCall(fn, args);
|
|
}
|
|
|
|
void emitDispose(CodeGenFunction &CGF, Address field) override {
|
|
field = CGF.Builder.CreateBitCast(field, CGF.Int8PtrTy->getPointerTo(0));
|
|
llvm::Value *value = CGF.Builder.CreateLoad(field);
|
|
|
|
CGF.BuildBlockRelease(value, Flags | BLOCK_BYREF_CALLER);
|
|
}
|
|
|
|
void profileImpl(llvm::FoldingSetNodeID &id) const override {
|
|
id.AddInteger(Flags.getBitMask());
|
|
}
|
|
};
|
|
|
|
/// Emits the copy/dispose helpers for an ARC __block __weak variable.
|
|
class ARCWeakByrefHelpers final : public BlockByrefHelpers {
|
|
public:
|
|
ARCWeakByrefHelpers(CharUnits alignment) : BlockByrefHelpers(alignment) {}
|
|
|
|
void emitCopy(CodeGenFunction &CGF, Address destField,
|
|
Address srcField) override {
|
|
CGF.EmitARCMoveWeak(destField, srcField);
|
|
}
|
|
|
|
void emitDispose(CodeGenFunction &CGF, Address field) override {
|
|
CGF.EmitARCDestroyWeak(field);
|
|
}
|
|
|
|
void profileImpl(llvm::FoldingSetNodeID &id) const override {
|
|
// 0 is distinguishable from all pointers and byref flags
|
|
id.AddInteger(0);
|
|
}
|
|
};
|
|
|
|
/// Emits the copy/dispose helpers for an ARC __block __strong variable
|
|
/// that's not of block-pointer type.
|
|
class ARCStrongByrefHelpers final : public BlockByrefHelpers {
|
|
public:
|
|
ARCStrongByrefHelpers(CharUnits alignment) : BlockByrefHelpers(alignment) {}
|
|
|
|
void emitCopy(CodeGenFunction &CGF, Address destField,
|
|
Address srcField) override {
|
|
// Do a "move" by copying the value and then zeroing out the old
|
|
// variable.
|
|
|
|
llvm::Value *value = CGF.Builder.CreateLoad(srcField);
|
|
|
|
llvm::Value *null =
|
|
llvm::ConstantPointerNull::get(cast<llvm::PointerType>(value->getType()));
|
|
|
|
if (CGF.CGM.getCodeGenOpts().OptimizationLevel == 0) {
|
|
CGF.Builder.CreateStore(null, destField);
|
|
CGF.EmitARCStoreStrongCall(destField, value, /*ignored*/ true);
|
|
CGF.EmitARCStoreStrongCall(srcField, null, /*ignored*/ true);
|
|
return;
|
|
}
|
|
CGF.Builder.CreateStore(value, destField);
|
|
CGF.Builder.CreateStore(null, srcField);
|
|
}
|
|
|
|
void emitDispose(CodeGenFunction &CGF, Address field) override {
|
|
CGF.EmitARCDestroyStrong(field, ARCImpreciseLifetime);
|
|
}
|
|
|
|
void profileImpl(llvm::FoldingSetNodeID &id) const override {
|
|
// 1 is distinguishable from all pointers and byref flags
|
|
id.AddInteger(1);
|
|
}
|
|
};
|
|
|
|
/// Emits the copy/dispose helpers for an ARC __block __strong
|
|
/// variable that's of block-pointer type.
|
|
class ARCStrongBlockByrefHelpers final : public BlockByrefHelpers {
|
|
public:
|
|
ARCStrongBlockByrefHelpers(CharUnits alignment)
|
|
: BlockByrefHelpers(alignment) {}
|
|
|
|
void emitCopy(CodeGenFunction &CGF, Address destField,
|
|
Address srcField) override {
|
|
// Do the copy with objc_retainBlock; that's all that
|
|
// _Block_object_assign would do anyway, and we'd have to pass the
|
|
// right arguments to make sure it doesn't get no-op'ed.
|
|
llvm::Value *oldValue = CGF.Builder.CreateLoad(srcField);
|
|
llvm::Value *copy = CGF.EmitARCRetainBlock(oldValue, /*mandatory*/ true);
|
|
CGF.Builder.CreateStore(copy, destField);
|
|
}
|
|
|
|
void emitDispose(CodeGenFunction &CGF, Address field) override {
|
|
CGF.EmitARCDestroyStrong(field, ARCImpreciseLifetime);
|
|
}
|
|
|
|
void profileImpl(llvm::FoldingSetNodeID &id) const override {
|
|
// 2 is distinguishable from all pointers and byref flags
|
|
id.AddInteger(2);
|
|
}
|
|
};
|
|
|
|
/// Emits the copy/dispose helpers for a __block variable with a
|
|
/// nontrivial copy constructor or destructor.
|
|
class CXXByrefHelpers final : public BlockByrefHelpers {
|
|
QualType VarType;
|
|
const Expr *CopyExpr;
|
|
|
|
public:
|
|
CXXByrefHelpers(CharUnits alignment, QualType type,
|
|
const Expr *copyExpr)
|
|
: BlockByrefHelpers(alignment), VarType(type), CopyExpr(copyExpr) {}
|
|
|
|
bool needsCopy() const override { return CopyExpr != nullptr; }
|
|
void emitCopy(CodeGenFunction &CGF, Address destField,
|
|
Address srcField) override {
|
|
if (!CopyExpr) return;
|
|
CGF.EmitSynthesizedCXXCopyCtor(destField, srcField, CopyExpr);
|
|
}
|
|
|
|
void emitDispose(CodeGenFunction &CGF, Address field) override {
|
|
EHScopeStack::stable_iterator cleanupDepth = CGF.EHStack.stable_begin();
|
|
CGF.PushDestructorCleanup(VarType, field);
|
|
CGF.PopCleanupBlocks(cleanupDepth);
|
|
}
|
|
|
|
void profileImpl(llvm::FoldingSetNodeID &id) const override {
|
|
id.AddPointer(VarType.getCanonicalType().getAsOpaquePtr());
|
|
}
|
|
};
|
|
} // end anonymous namespace
|
|
|
|
static llvm::Constant *
|
|
generateByrefCopyHelper(CodeGenFunction &CGF, const BlockByrefInfo &byrefInfo,
|
|
BlockByrefHelpers &generator) {
|
|
ASTContext &Context = CGF.getContext();
|
|
|
|
QualType R = Context.VoidTy;
|
|
|
|
FunctionArgList args;
|
|
ImplicitParamDecl dst(CGF.getContext(), nullptr, SourceLocation(), nullptr,
|
|
Context.VoidPtrTy);
|
|
args.push_back(&dst);
|
|
|
|
ImplicitParamDecl src(CGF.getContext(), nullptr, SourceLocation(), nullptr,
|
|
Context.VoidPtrTy);
|
|
args.push_back(&src);
|
|
|
|
const CGFunctionInfo &FI =
|
|
CGF.CGM.getTypes().arrangeBuiltinFunctionDeclaration(R, args);
|
|
|
|
llvm::FunctionType *LTy = CGF.CGM.getTypes().GetFunctionType(FI);
|
|
|
|
// FIXME: We'd like to put these into a mergable by content, with
|
|
// internal linkage.
|
|
llvm::Function *Fn =
|
|
llvm::Function::Create(LTy, llvm::GlobalValue::InternalLinkage,
|
|
"__Block_byref_object_copy_", &CGF.CGM.getModule());
|
|
|
|
IdentifierInfo *II
|
|
= &Context.Idents.get("__Block_byref_object_copy_");
|
|
|
|
FunctionDecl *FD = FunctionDecl::Create(Context,
|
|
Context.getTranslationUnitDecl(),
|
|
SourceLocation(),
|
|
SourceLocation(), II, R, nullptr,
|
|
SC_Static,
|
|
false, false);
|
|
|
|
CGF.CGM.SetInternalFunctionAttributes(nullptr, Fn, FI);
|
|
|
|
CGF.StartFunction(FD, R, Fn, FI, args);
|
|
|
|
if (generator.needsCopy()) {
|
|
llvm::Type *byrefPtrType = byrefInfo.Type->getPointerTo(0);
|
|
|
|
// dst->x
|
|
Address destField = CGF.GetAddrOfLocalVar(&dst);
|
|
destField = Address(CGF.Builder.CreateLoad(destField),
|
|
byrefInfo.ByrefAlignment);
|
|
destField = CGF.Builder.CreateBitCast(destField, byrefPtrType);
|
|
destField = CGF.emitBlockByrefAddress(destField, byrefInfo, false,
|
|
"dest-object");
|
|
|
|
// src->x
|
|
Address srcField = CGF.GetAddrOfLocalVar(&src);
|
|
srcField = Address(CGF.Builder.CreateLoad(srcField),
|
|
byrefInfo.ByrefAlignment);
|
|
srcField = CGF.Builder.CreateBitCast(srcField, byrefPtrType);
|
|
srcField = CGF.emitBlockByrefAddress(srcField, byrefInfo, false,
|
|
"src-object");
|
|
|
|
generator.emitCopy(CGF, destField, srcField);
|
|
}
|
|
|
|
CGF.FinishFunction();
|
|
|
|
return llvm::ConstantExpr::getBitCast(Fn, CGF.Int8PtrTy);
|
|
}
|
|
|
|
/// Build the copy helper for a __block variable.
|
|
static llvm::Constant *buildByrefCopyHelper(CodeGenModule &CGM,
|
|
const BlockByrefInfo &byrefInfo,
|
|
BlockByrefHelpers &generator) {
|
|
CodeGenFunction CGF(CGM);
|
|
return generateByrefCopyHelper(CGF, byrefInfo, generator);
|
|
}
|
|
|
|
/// Generate code for a __block variable's dispose helper.
|
|
static llvm::Constant *
|
|
generateByrefDisposeHelper(CodeGenFunction &CGF,
|
|
const BlockByrefInfo &byrefInfo,
|
|
BlockByrefHelpers &generator) {
|
|
ASTContext &Context = CGF.getContext();
|
|
QualType R = Context.VoidTy;
|
|
|
|
FunctionArgList args;
|
|
ImplicitParamDecl src(CGF.getContext(), nullptr, SourceLocation(), nullptr,
|
|
Context.VoidPtrTy);
|
|
args.push_back(&src);
|
|
|
|
const CGFunctionInfo &FI =
|
|
CGF.CGM.getTypes().arrangeBuiltinFunctionDeclaration(R, args);
|
|
|
|
llvm::FunctionType *LTy = CGF.CGM.getTypes().GetFunctionType(FI);
|
|
|
|
// FIXME: We'd like to put these into a mergable by content, with
|
|
// internal linkage.
|
|
llvm::Function *Fn =
|
|
llvm::Function::Create(LTy, llvm::GlobalValue::InternalLinkage,
|
|
"__Block_byref_object_dispose_",
|
|
&CGF.CGM.getModule());
|
|
|
|
IdentifierInfo *II
|
|
= &Context.Idents.get("__Block_byref_object_dispose_");
|
|
|
|
FunctionDecl *FD = FunctionDecl::Create(Context,
|
|
Context.getTranslationUnitDecl(),
|
|
SourceLocation(),
|
|
SourceLocation(), II, R, nullptr,
|
|
SC_Static,
|
|
false, false);
|
|
|
|
CGF.CGM.SetInternalFunctionAttributes(nullptr, Fn, FI);
|
|
|
|
CGF.StartFunction(FD, R, Fn, FI, args);
|
|
|
|
if (generator.needsDispose()) {
|
|
Address addr = CGF.GetAddrOfLocalVar(&src);
|
|
addr = Address(CGF.Builder.CreateLoad(addr), byrefInfo.ByrefAlignment);
|
|
auto byrefPtrType = byrefInfo.Type->getPointerTo(0);
|
|
addr = CGF.Builder.CreateBitCast(addr, byrefPtrType);
|
|
addr = CGF.emitBlockByrefAddress(addr, byrefInfo, false, "object");
|
|
|
|
generator.emitDispose(CGF, addr);
|
|
}
|
|
|
|
CGF.FinishFunction();
|
|
|
|
return llvm::ConstantExpr::getBitCast(Fn, CGF.Int8PtrTy);
|
|
}
|
|
|
|
/// Build the dispose helper for a __block variable.
|
|
static llvm::Constant *buildByrefDisposeHelper(CodeGenModule &CGM,
|
|
const BlockByrefInfo &byrefInfo,
|
|
BlockByrefHelpers &generator) {
|
|
CodeGenFunction CGF(CGM);
|
|
return generateByrefDisposeHelper(CGF, byrefInfo, generator);
|
|
}
|
|
|
|
/// Lazily build the copy and dispose helpers for a __block variable
|
|
/// with the given information.
|
|
template <class T>
|
|
static T *buildByrefHelpers(CodeGenModule &CGM, const BlockByrefInfo &byrefInfo,
|
|
T &&generator) {
|
|
llvm::FoldingSetNodeID id;
|
|
generator.Profile(id);
|
|
|
|
void *insertPos;
|
|
BlockByrefHelpers *node
|
|
= CGM.ByrefHelpersCache.FindNodeOrInsertPos(id, insertPos);
|
|
if (node) return static_cast<T*>(node);
|
|
|
|
generator.CopyHelper = buildByrefCopyHelper(CGM, byrefInfo, generator);
|
|
generator.DisposeHelper = buildByrefDisposeHelper(CGM, byrefInfo, generator);
|
|
|
|
T *copy = new (CGM.getContext()) T(std::move(generator));
|
|
CGM.ByrefHelpersCache.InsertNode(copy, insertPos);
|
|
return copy;
|
|
}
|
|
|
|
/// Build the copy and dispose helpers for the given __block variable
|
|
/// emission. Places the helpers in the global cache. Returns null
|
|
/// if no helpers are required.
|
|
BlockByrefHelpers *
|
|
CodeGenFunction::buildByrefHelpers(llvm::StructType &byrefType,
|
|
const AutoVarEmission &emission) {
|
|
const VarDecl &var = *emission.Variable;
|
|
QualType type = var.getType();
|
|
|
|
auto &byrefInfo = getBlockByrefInfo(&var);
|
|
|
|
// The alignment we care about for the purposes of uniquing byref
|
|
// helpers is the alignment of the actual byref value field.
|
|
CharUnits valueAlignment =
|
|
byrefInfo.ByrefAlignment.alignmentAtOffset(byrefInfo.FieldOffset);
|
|
|
|
if (const CXXRecordDecl *record = type->getAsCXXRecordDecl()) {
|
|
const Expr *copyExpr = CGM.getContext().getBlockVarCopyInits(&var);
|
|
if (!copyExpr && record->hasTrivialDestructor()) return nullptr;
|
|
|
|
return ::buildByrefHelpers(
|
|
CGM, byrefInfo, CXXByrefHelpers(valueAlignment, type, copyExpr));
|
|
}
|
|
|
|
// Otherwise, if we don't have a retainable type, there's nothing to do.
|
|
// that the runtime does extra copies.
|
|
if (!type->isObjCRetainableType()) return nullptr;
|
|
|
|
Qualifiers qs = type.getQualifiers();
|
|
|
|
// If we have lifetime, that dominates.
|
|
if (Qualifiers::ObjCLifetime lifetime = qs.getObjCLifetime()) {
|
|
switch (lifetime) {
|
|
case Qualifiers::OCL_None: llvm_unreachable("impossible");
|
|
|
|
// These are just bits as far as the runtime is concerned.
|
|
case Qualifiers::OCL_ExplicitNone:
|
|
case Qualifiers::OCL_Autoreleasing:
|
|
return nullptr;
|
|
|
|
// Tell the runtime that this is ARC __weak, called by the
|
|
// byref routines.
|
|
case Qualifiers::OCL_Weak:
|
|
return ::buildByrefHelpers(CGM, byrefInfo,
|
|
ARCWeakByrefHelpers(valueAlignment));
|
|
|
|
// ARC __strong __block variables need to be retained.
|
|
case Qualifiers::OCL_Strong:
|
|
// Block pointers need to be copied, and there's no direct
|
|
// transfer possible.
|
|
if (type->isBlockPointerType()) {
|
|
return ::buildByrefHelpers(CGM, byrefInfo,
|
|
ARCStrongBlockByrefHelpers(valueAlignment));
|
|
|
|
// Otherwise, we transfer ownership of the retain from the stack
|
|
// to the heap.
|
|
} else {
|
|
return ::buildByrefHelpers(CGM, byrefInfo,
|
|
ARCStrongByrefHelpers(valueAlignment));
|
|
}
|
|
}
|
|
llvm_unreachable("fell out of lifetime switch!");
|
|
}
|
|
|
|
BlockFieldFlags flags;
|
|
if (type->isBlockPointerType()) {
|
|
flags |= BLOCK_FIELD_IS_BLOCK;
|
|
} else if (CGM.getContext().isObjCNSObjectType(type) ||
|
|
type->isObjCObjectPointerType()) {
|
|
flags |= BLOCK_FIELD_IS_OBJECT;
|
|
} else {
|
|
return nullptr;
|
|
}
|
|
|
|
if (type.isObjCGCWeak())
|
|
flags |= BLOCK_FIELD_IS_WEAK;
|
|
|
|
return ::buildByrefHelpers(CGM, byrefInfo,
|
|
ObjectByrefHelpers(valueAlignment, flags));
|
|
}
|
|
|
|
Address CodeGenFunction::emitBlockByrefAddress(Address baseAddr,
|
|
const VarDecl *var,
|
|
bool followForward) {
|
|
auto &info = getBlockByrefInfo(var);
|
|
return emitBlockByrefAddress(baseAddr, info, followForward, var->getName());
|
|
}
|
|
|
|
Address CodeGenFunction::emitBlockByrefAddress(Address baseAddr,
|
|
const BlockByrefInfo &info,
|
|
bool followForward,
|
|
const llvm::Twine &name) {
|
|
// Chase the forwarding address if requested.
|
|
if (followForward) {
|
|
Address forwardingAddr =
|
|
Builder.CreateStructGEP(baseAddr, 1, getPointerSize(), "forwarding");
|
|
baseAddr = Address(Builder.CreateLoad(forwardingAddr), info.ByrefAlignment);
|
|
}
|
|
|
|
return Builder.CreateStructGEP(baseAddr, info.FieldIndex,
|
|
info.FieldOffset, name);
|
|
}
|
|
|
|
/// BuildByrefInfo - This routine changes a __block variable declared as T x
|
|
/// into:
|
|
///
|
|
/// struct {
|
|
/// void *__isa;
|
|
/// void *__forwarding;
|
|
/// int32_t __flags;
|
|
/// int32_t __size;
|
|
/// void *__copy_helper; // only if needed
|
|
/// void *__destroy_helper; // only if needed
|
|
/// void *__byref_variable_layout;// only if needed
|
|
/// char padding[X]; // only if needed
|
|
/// T x;
|
|
/// } x
|
|
///
|
|
const BlockByrefInfo &CodeGenFunction::getBlockByrefInfo(const VarDecl *D) {
|
|
auto it = BlockByrefInfos.find(D);
|
|
if (it != BlockByrefInfos.end())
|
|
return it->second;
|
|
|
|
llvm::StructType *byrefType =
|
|
llvm::StructType::create(getLLVMContext(),
|
|
"struct.__block_byref_" + D->getNameAsString());
|
|
|
|
QualType Ty = D->getType();
|
|
|
|
CharUnits size;
|
|
SmallVector<llvm::Type *, 8> types;
|
|
|
|
// void *__isa;
|
|
types.push_back(Int8PtrTy);
|
|
size += getPointerSize();
|
|
|
|
// void *__forwarding;
|
|
types.push_back(llvm::PointerType::getUnqual(byrefType));
|
|
size += getPointerSize();
|
|
|
|
// int32_t __flags;
|
|
types.push_back(Int32Ty);
|
|
size += CharUnits::fromQuantity(4);
|
|
|
|
// int32_t __size;
|
|
types.push_back(Int32Ty);
|
|
size += CharUnits::fromQuantity(4);
|
|
|
|
// Note that this must match *exactly* the logic in buildByrefHelpers.
|
|
bool hasCopyAndDispose = getContext().BlockRequiresCopying(Ty, D);
|
|
if (hasCopyAndDispose) {
|
|
/// void *__copy_helper;
|
|
types.push_back(Int8PtrTy);
|
|
size += getPointerSize();
|
|
|
|
/// void *__destroy_helper;
|
|
types.push_back(Int8PtrTy);
|
|
size += getPointerSize();
|
|
}
|
|
|
|
bool HasByrefExtendedLayout = false;
|
|
Qualifiers::ObjCLifetime Lifetime;
|
|
if (getContext().getByrefLifetime(Ty, Lifetime, HasByrefExtendedLayout) &&
|
|
HasByrefExtendedLayout) {
|
|
/// void *__byref_variable_layout;
|
|
types.push_back(Int8PtrTy);
|
|
size += CharUnits::fromQuantity(PointerSizeInBytes);
|
|
}
|
|
|
|
// T x;
|
|
llvm::Type *varTy = ConvertTypeForMem(Ty);
|
|
|
|
bool packed = false;
|
|
CharUnits varAlign = getContext().getDeclAlign(D);
|
|
CharUnits varOffset = size.alignTo(varAlign);
|
|
|
|
// We may have to insert padding.
|
|
if (varOffset != size) {
|
|
llvm::Type *paddingTy =
|
|
llvm::ArrayType::get(Int8Ty, (varOffset - size).getQuantity());
|
|
|
|
types.push_back(paddingTy);
|
|
size = varOffset;
|
|
|
|
// Conversely, we might have to prevent LLVM from inserting padding.
|
|
} else if (CGM.getDataLayout().getABITypeAlignment(varTy)
|
|
> varAlign.getQuantity()) {
|
|
packed = true;
|
|
}
|
|
types.push_back(varTy);
|
|
|
|
byrefType->setBody(types, packed);
|
|
|
|
BlockByrefInfo info;
|
|
info.Type = byrefType;
|
|
info.FieldIndex = types.size() - 1;
|
|
info.FieldOffset = varOffset;
|
|
info.ByrefAlignment = std::max(varAlign, getPointerAlign());
|
|
|
|
auto pair = BlockByrefInfos.insert({D, info});
|
|
assert(pair.second && "info was inserted recursively?");
|
|
return pair.first->second;
|
|
}
|
|
|
|
/// Initialize the structural components of a __block variable, i.e.
|
|
/// everything but the actual object.
|
|
void CodeGenFunction::emitByrefStructureInit(const AutoVarEmission &emission) {
|
|
// Find the address of the local.
|
|
Address addr = emission.Addr;
|
|
|
|
// That's an alloca of the byref structure type.
|
|
llvm::StructType *byrefType = cast<llvm::StructType>(
|
|
cast<llvm::PointerType>(addr.getPointer()->getType())->getElementType());
|
|
|
|
unsigned nextHeaderIndex = 0;
|
|
CharUnits nextHeaderOffset;
|
|
auto storeHeaderField = [&](llvm::Value *value, CharUnits fieldSize,
|
|
const Twine &name) {
|
|
auto fieldAddr = Builder.CreateStructGEP(addr, nextHeaderIndex,
|
|
nextHeaderOffset, name);
|
|
Builder.CreateStore(value, fieldAddr);
|
|
|
|
nextHeaderIndex++;
|
|
nextHeaderOffset += fieldSize;
|
|
};
|
|
|
|
// Build the byref helpers if necessary. This is null if we don't need any.
|
|
BlockByrefHelpers *helpers = buildByrefHelpers(*byrefType, emission);
|
|
|
|
const VarDecl &D = *emission.Variable;
|
|
QualType type = D.getType();
|
|
|
|
bool HasByrefExtendedLayout;
|
|
Qualifiers::ObjCLifetime ByrefLifetime;
|
|
bool ByRefHasLifetime =
|
|
getContext().getByrefLifetime(type, ByrefLifetime, HasByrefExtendedLayout);
|
|
|
|
llvm::Value *V;
|
|
|
|
// Initialize the 'isa', which is just 0 or 1.
|
|
int isa = 0;
|
|
if (type.isObjCGCWeak())
|
|
isa = 1;
|
|
V = Builder.CreateIntToPtr(Builder.getInt32(isa), Int8PtrTy, "isa");
|
|
storeHeaderField(V, getPointerSize(), "byref.isa");
|
|
|
|
// Store the address of the variable into its own forwarding pointer.
|
|
storeHeaderField(addr.getPointer(), getPointerSize(), "byref.forwarding");
|
|
|
|
// Blocks ABI:
|
|
// c) the flags field is set to either 0 if no helper functions are
|
|
// needed or BLOCK_BYREF_HAS_COPY_DISPOSE if they are,
|
|
BlockFlags flags;
|
|
if (helpers) flags |= BLOCK_BYREF_HAS_COPY_DISPOSE;
|
|
if (ByRefHasLifetime) {
|
|
if (HasByrefExtendedLayout) flags |= BLOCK_BYREF_LAYOUT_EXTENDED;
|
|
else switch (ByrefLifetime) {
|
|
case Qualifiers::OCL_Strong:
|
|
flags |= BLOCK_BYREF_LAYOUT_STRONG;
|
|
break;
|
|
case Qualifiers::OCL_Weak:
|
|
flags |= BLOCK_BYREF_LAYOUT_WEAK;
|
|
break;
|
|
case Qualifiers::OCL_ExplicitNone:
|
|
flags |= BLOCK_BYREF_LAYOUT_UNRETAINED;
|
|
break;
|
|
case Qualifiers::OCL_None:
|
|
if (!type->isObjCObjectPointerType() && !type->isBlockPointerType())
|
|
flags |= BLOCK_BYREF_LAYOUT_NON_OBJECT;
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
if (CGM.getLangOpts().ObjCGCBitmapPrint) {
|
|
printf("\n Inline flag for BYREF variable layout (%d):", flags.getBitMask());
|
|
if (flags & BLOCK_BYREF_HAS_COPY_DISPOSE)
|
|
printf(" BLOCK_BYREF_HAS_COPY_DISPOSE");
|
|
if (flags & BLOCK_BYREF_LAYOUT_MASK) {
|
|
BlockFlags ThisFlag(flags.getBitMask() & BLOCK_BYREF_LAYOUT_MASK);
|
|
if (ThisFlag == BLOCK_BYREF_LAYOUT_EXTENDED)
|
|
printf(" BLOCK_BYREF_LAYOUT_EXTENDED");
|
|
if (ThisFlag == BLOCK_BYREF_LAYOUT_STRONG)
|
|
printf(" BLOCK_BYREF_LAYOUT_STRONG");
|
|
if (ThisFlag == BLOCK_BYREF_LAYOUT_WEAK)
|
|
printf(" BLOCK_BYREF_LAYOUT_WEAK");
|
|
if (ThisFlag == BLOCK_BYREF_LAYOUT_UNRETAINED)
|
|
printf(" BLOCK_BYREF_LAYOUT_UNRETAINED");
|
|
if (ThisFlag == BLOCK_BYREF_LAYOUT_NON_OBJECT)
|
|
printf(" BLOCK_BYREF_LAYOUT_NON_OBJECT");
|
|
}
|
|
printf("\n");
|
|
}
|
|
}
|
|
storeHeaderField(llvm::ConstantInt::get(IntTy, flags.getBitMask()),
|
|
getIntSize(), "byref.flags");
|
|
|
|
CharUnits byrefSize = CGM.GetTargetTypeStoreSize(byrefType);
|
|
V = llvm::ConstantInt::get(IntTy, byrefSize.getQuantity());
|
|
storeHeaderField(V, getIntSize(), "byref.size");
|
|
|
|
if (helpers) {
|
|
storeHeaderField(helpers->CopyHelper, getPointerSize(),
|
|
"byref.copyHelper");
|
|
storeHeaderField(helpers->DisposeHelper, getPointerSize(),
|
|
"byref.disposeHelper");
|
|
}
|
|
|
|
if (ByRefHasLifetime && HasByrefExtendedLayout) {
|
|
auto layoutInfo = CGM.getObjCRuntime().BuildByrefLayout(CGM, type);
|
|
storeHeaderField(layoutInfo, getPointerSize(), "byref.layout");
|
|
}
|
|
}
|
|
|
|
void CodeGenFunction::BuildBlockRelease(llvm::Value *V, BlockFieldFlags flags) {
|
|
llvm::Value *F = CGM.getBlockObjectDispose();
|
|
llvm::Value *args[] = {
|
|
Builder.CreateBitCast(V, Int8PtrTy),
|
|
llvm::ConstantInt::get(Int32Ty, flags.getBitMask())
|
|
};
|
|
EmitNounwindRuntimeCall(F, args); // FIXME: throwing destructors?
|
|
}
|
|
|
|
namespace {
|
|
/// Release a __block variable.
|
|
struct CallBlockRelease final : EHScopeStack::Cleanup {
|
|
llvm::Value *Addr;
|
|
CallBlockRelease(llvm::Value *Addr) : Addr(Addr) {}
|
|
|
|
void Emit(CodeGenFunction &CGF, Flags flags) override {
|
|
// Should we be passing FIELD_IS_WEAK here?
|
|
CGF.BuildBlockRelease(Addr, BLOCK_FIELD_IS_BYREF);
|
|
}
|
|
};
|
|
} // end anonymous namespace
|
|
|
|
/// Enter a cleanup to destroy a __block variable. Note that this
|
|
/// cleanup should be a no-op if the variable hasn't left the stack
|
|
/// yet; if a cleanup is required for the variable itself, that needs
|
|
/// to be done externally.
|
|
void CodeGenFunction::enterByrefCleanup(const AutoVarEmission &emission) {
|
|
// We don't enter this cleanup if we're in pure-GC mode.
|
|
if (CGM.getLangOpts().getGC() == LangOptions::GCOnly)
|
|
return;
|
|
|
|
EHStack.pushCleanup<CallBlockRelease>(NormalAndEHCleanup,
|
|
emission.Addr.getPointer());
|
|
}
|
|
|
|
/// Adjust the declaration of something from the blocks API.
|
|
static void configureBlocksRuntimeObject(CodeGenModule &CGM,
|
|
llvm::Constant *C) {
|
|
auto *GV = cast<llvm::GlobalValue>(C->stripPointerCasts());
|
|
|
|
if (CGM.getTarget().getTriple().isOSBinFormatCOFF()) {
|
|
IdentifierInfo &II = CGM.getContext().Idents.get(C->getName());
|
|
TranslationUnitDecl *TUDecl = CGM.getContext().getTranslationUnitDecl();
|
|
DeclContext *DC = TranslationUnitDecl::castToDeclContext(TUDecl);
|
|
|
|
assert((isa<llvm::Function>(C->stripPointerCasts()) ||
|
|
isa<llvm::GlobalVariable>(C->stripPointerCasts())) &&
|
|
"expected Function or GlobalVariable");
|
|
|
|
const NamedDecl *ND = nullptr;
|
|
for (const auto &Result : DC->lookup(&II))
|
|
if ((ND = dyn_cast<FunctionDecl>(Result)) ||
|
|
(ND = dyn_cast<VarDecl>(Result)))
|
|
break;
|
|
|
|
// TODO: support static blocks runtime
|
|
if (GV->isDeclaration() && (!ND || !ND->hasAttr<DLLExportAttr>())) {
|
|
GV->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass);
|
|
GV->setLinkage(llvm::GlobalValue::ExternalLinkage);
|
|
} else {
|
|
GV->setDLLStorageClass(llvm::GlobalValue::DLLExportStorageClass);
|
|
GV->setLinkage(llvm::GlobalValue::ExternalLinkage);
|
|
}
|
|
}
|
|
|
|
if (!CGM.getLangOpts().BlocksRuntimeOptional)
|
|
return;
|
|
|
|
if (GV->isDeclaration() && GV->hasExternalLinkage())
|
|
GV->setLinkage(llvm::GlobalValue::ExternalWeakLinkage);
|
|
}
|
|
|
|
llvm::Constant *CodeGenModule::getBlockObjectDispose() {
|
|
if (BlockObjectDispose)
|
|
return BlockObjectDispose;
|
|
|
|
llvm::Type *args[] = { Int8PtrTy, Int32Ty };
|
|
llvm::FunctionType *fty
|
|
= llvm::FunctionType::get(VoidTy, args, false);
|
|
BlockObjectDispose = CreateRuntimeFunction(fty, "_Block_object_dispose");
|
|
configureBlocksRuntimeObject(*this, BlockObjectDispose);
|
|
return BlockObjectDispose;
|
|
}
|
|
|
|
llvm::Constant *CodeGenModule::getBlockObjectAssign() {
|
|
if (BlockObjectAssign)
|
|
return BlockObjectAssign;
|
|
|
|
llvm::Type *args[] = { Int8PtrTy, Int8PtrTy, Int32Ty };
|
|
llvm::FunctionType *fty
|
|
= llvm::FunctionType::get(VoidTy, args, false);
|
|
BlockObjectAssign = CreateRuntimeFunction(fty, "_Block_object_assign");
|
|
configureBlocksRuntimeObject(*this, BlockObjectAssign);
|
|
return BlockObjectAssign;
|
|
}
|
|
|
|
llvm::Constant *CodeGenModule::getNSConcreteGlobalBlock() {
|
|
if (NSConcreteGlobalBlock)
|
|
return NSConcreteGlobalBlock;
|
|
|
|
NSConcreteGlobalBlock = GetOrCreateLLVMGlobal("_NSConcreteGlobalBlock",
|
|
Int8PtrTy->getPointerTo(),
|
|
nullptr);
|
|
configureBlocksRuntimeObject(*this, NSConcreteGlobalBlock);
|
|
return NSConcreteGlobalBlock;
|
|
}
|
|
|
|
llvm::Constant *CodeGenModule::getNSConcreteStackBlock() {
|
|
if (NSConcreteStackBlock)
|
|
return NSConcreteStackBlock;
|
|
|
|
NSConcreteStackBlock = GetOrCreateLLVMGlobal("_NSConcreteStackBlock",
|
|
Int8PtrTy->getPointerTo(),
|
|
nullptr);
|
|
configureBlocksRuntimeObject(*this, NSConcreteStackBlock);
|
|
return NSConcreteStackBlock;
|
|
}
|