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LLVM 23.0.0git
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#include "CoroInternal.h"#include "llvm/ADT/ScopeExit.h"#include "llvm/ADT/SmallString.h"#include "llvm/Analysis/StackLifetime.h"#include "llvm/IR/DIBuilder.h"#include "llvm/IR/DebugInfo.h"#include "llvm/IR/Dominators.h"#include "llvm/IR/IRBuilder.h"#include "llvm/IR/InstIterator.h"#include "llvm/IR/IntrinsicInst.h"#include "llvm/IR/MDBuilder.h"#include "llvm/IR/Module.h"#include "llvm/Support/Compiler.h"#include "llvm/Support/Debug.h"#include "llvm/Support/OptimizedStructLayout.h"#include "llvm/Transforms/Coroutines/ABI.h"#include "llvm/Transforms/Coroutines/CoroInstr.h"#include "llvm/Transforms/Coroutines/MaterializationUtils.h"#include "llvm/Transforms/Coroutines/SpillUtils.h"#include "llvm/Transforms/Coroutines/SuspendCrossingInfo.h"#include "llvm/Transforms/Utils/BasicBlockUtils.h"#include "llvm/Transforms/Utils/Local.h"#include "llvm/Transforms/Utils/PromoteMemToReg.h"#include <algorithm>#include <optional>Go to the source code of this file.
Macros | |
| #define | DEBUG_TYPE "coro-frame" |
Functions | |
| static void | dumpSpills (StringRef Title, const coro::SpillInfo &Spills) |
| static void | dumpAllocas (const SmallVectorImpl< coro::AllocaInfo > &Allocas) |
| static void | cacheDIVar (FrameDataInfo &FrameData, DenseMap< Value *, DILocalVariable * > &DIVarCache) |
| static StringRef | solveTypeName (Type *Ty) |
| Create name for Type. | |
| static DIType * | solveDIType (DIBuilder &Builder, Type *Ty, const DataLayout &Layout, DIScope *Scope, unsigned LineNum, DenseMap< Type *, DIType * > &DITypeCache) |
| static void | buildFrameDebugInfo (Function &F, coro::Shape &Shape, FrameDataInfo &FrameData) |
| Build artificial debug info for C++ coroutine frames to allow users to inspect the contents of the frame directly. | |
| static void | buildFrameLayout (Function &F, coro::Shape &Shape, FrameDataInfo &FrameData, bool OptimizeFrame) |
| static Type * | extractByvalIfArgument (Value *MaybeArgument) |
| If MaybeArgument is a byval Argument, return its byval type. | |
| static void | createStoreIntoFrame (IRBuilder<> &Builder, Value *Def, Type *ByValTy, const coro::Shape &Shape, const FrameDataInfo &FrameData) |
| Store Def into the coroutine frame. | |
| static Value * | createGEPToFramePointer (const FrameDataInfo &FrameData, IRBuilder<> &Builder, coro::Shape &Shape, Value *Orig) |
| Returns a pointer into the coroutine frame at the offset where Orig is located. | |
| template<DbgVariableRecord::LocationType record_type> | |
| static TinyPtrVector< DbgVariableRecord * > | findDbgRecordsThroughLoads (Function &F, Value *Def) |
| Find dbg.declare or dbg.declare_value records referencing Def. | |
| static void | handleAccessBeforeCoroBegin (const FrameDataInfo &FrameData, coro::Shape &Shape, IRBuilder<> &Builder, AllocaInst *Alloca) |
| static void | insertSpills (const FrameDataInfo &FrameData, coro::Shape &Shape) |
| static void | movePHIValuesToInsertedBlock (BasicBlock *SuccBB, BasicBlock *InsertedBB, BasicBlock *PredBB, PHINode *UntilPHI=nullptr) |
| static void | rewritePHIsForCleanupPad (BasicBlock *CleanupPadBB, CleanupPadInst *CleanupPad) |
| static void | cleanupSinglePredPHIs (Function &F) |
| static void | rewritePHIs (BasicBlock &BB) |
| static void | rewritePHIs (Function &F) |
| static BasicBlock * | splitBlockIfNotFirst (Instruction *I, const Twine &Name) |
| static void | splitAround (Instruction *I, const Twine &Name) |
| static bool | willLeaveFunctionImmediatelyAfter (BasicBlock *BB, unsigned depth=3) |
| After we split the coroutine, will the given basic block be along an obvious exit path for the resumption function? | |
| static bool | localAllocaNeedsStackSave (CoroAllocaAllocInst *AI) |
| static void | lowerLocalAllocas (ArrayRef< CoroAllocaAllocInst * > LocalAllocas, SmallVectorImpl< Instruction * > &DeadInsts) |
| Turn each of the given local allocas into a normal (dynamic) alloca instruction. | |
| static Value * | emitGetSwiftErrorValue (IRBuilder<> &Builder, Type *ValueTy, coro::Shape &Shape) |
| Get the current swifterror value. | |
| static Value * | emitSetSwiftErrorValue (IRBuilder<> &Builder, Value *V, coro::Shape &Shape) |
| Set the given value as the current swifterror value. | |
| static Value * | emitSetAndGetSwiftErrorValueAround (Instruction *Call, AllocaInst *Alloca, coro::Shape &Shape) |
| Set the swifterror value from the given alloca before a call, then put in back in the alloca afterwards. | |
| static void | eliminateSwiftErrorAlloca (Function &F, AllocaInst *Alloca, coro::Shape &Shape) |
| Eliminate a formerly-swifterror alloca by inserting the get/set intrinsics and attempting to MemToReg the alloca away. | |
| static void | eliminateSwiftErrorArgument (Function &F, Argument &Arg, coro::Shape &Shape, SmallVectorImpl< AllocaInst * > &AllocasToPromote) |
| "Eliminate" a swifterror argument by reducing it to the alloca case and then loading and storing in the prologue and epilog. | |
| static void | eliminateSwiftError (Function &F, coro::Shape &Shape) |
| Eliminate all problematic uses of swifterror arguments and allocas from the function. | |
| static void | sinkLifetimeStartMarkers (Function &F, coro::Shape &Shape, SuspendCrossingInfo &Checker, const DominatorTree &DT) |
| For each local variable that all of its user are only used inside one of suspended region, we sink their lifetime.start markers to the place where after the suspend block. | |
| static std::optional< std::pair< Value &, DIExpression & > > | salvageDebugInfoImpl (SmallDenseMap< Argument *, AllocaInst *, 4 > &ArgToAllocaMap, bool UseEntryValue, Function *F, Value *Storage, DIExpression *Expr, bool SkipOutermostLoad) |
| #define DEBUG_TYPE "coro-frame" |
Definition at line 46 of file CoroFrame.cpp.
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Build artificial debug info for C++ coroutine frames to allow users to inspect the contents of the frame directly.
Create Debug information for coroutine frame with debug name "__coro_frame". The debug information for the fields of coroutine frame is constructed from the following way:
Definition at line 619 of file CoroFrame.cpp.
References llvm::coro::Shape::ABI, assert(), cacheDIVar(), llvm::DIBuilder::createAutoVariable(), llvm::DIBuilder::createBasicType(), llvm::DIBuilder::createExpression(), llvm::DIBuilder::createMemberType(), llvm::DIBuilder::createPointerType(), llvm::DIBuilder::createStructType(), llvm::DbgVariableRecord::Declare, llvm::coro::Shape::SwitchLoweringStorage::DestroyOffset, llvm::dyn_cast(), llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::end(), F, llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::find(), llvm::coro::Shape::FrameAlign, llvm::coro::Shape::FramePtr, llvm::coro::Shape::FrameSize, llvm::DICompileUnit::FullDebug, llvm::MDNode::get(), llvm::MDTuple::get(), llvm::ValueAsMetadata::get(), llvm::AllocaInst::getAllocatedType(), llvm::AllocaInst::getAllocationSize(), llvm::MDNode::getContext(), llvm::DIScope::getFile(), llvm::details::FixedOrScalableQuantity< LeafTy, ValueTy >::getFixedValue(), llvm::coro::Shape::getIndexType(), llvm::coro::Shape::getInsertPtAfterFramePtr(), llvm::DIType::getName(), llvm::DIBuilder::getOrCreateArray(), llvm::DataLayout::getPointerABIAlignment(), llvm::DataLayout::getPointerSizeInBits(), llvm::coro::Shape::getSwitchResumePointerType(), llvm::DataLayout::getTypeSizeInBits(), llvm::coro::Shape::SwitchLoweringStorage::IndexAlign, llvm::coro::Shape::SwitchLoweringStorage::IndexOffset, llvm::dwarf::isCPlusPlus(), llvm::Offset, llvm::SmallVectorTemplateBase< T, bool >::push_back(), llvm::DIBuilder::replaceArrays(), llvm::MDNode::replaceOperandWith(), Size, solveDIType(), llvm::StringRef::str(), llvm::Twine::str(), llvm::coro::Switch, llvm::coro::Shape::SwitchLowering, and llvm::Align::value().
Referenced by llvm::coro::BaseABI::buildCoroutineFrame().
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Definition at line 773 of file CoroFrame.cpp.
References A(), llvm::coro::Shape::ABI, llvm::alignTo(), assert(), llvm::coro::Async, llvm::coro::Shape::AsyncLowering, B(), llvm::coro::Shape::AsyncLoweringStorage::ContextHeaderSize, llvm::coro::Shape::AsyncLoweringStorage::ContextSize, llvm::coro::Shape::CoroSuspends, llvm::coro::Shape::SwitchLoweringStorage::DestroyOffset, DL, llvm::dyn_cast(), F, llvm::coro::Shape::FrameAlign, llvm::coro::Shape::AsyncLoweringStorage::FrameOffset, llvm::coro::Shape::FrameSize, llvm::coro::Shape::AsyncLoweringStorage::getContextAlignment(), llvm::Type::getIntNTy(), llvm::coro::Shape::getPromiseAlloca(), llvm::coro::Shape::getRetconCoroId(), llvm::coro::Shape::getSwitchResumePointerType(), llvm::coro::Shape::SwitchLoweringStorage::IndexAlign, llvm::coro::Shape::SwitchLoweringStorage::IndexOffset, llvm::coro::Shape::SwitchLoweringStorage::IndexType, llvm::coro::Shape::RetconLoweringStorage::IsFrameInlineInStorage, llvm::Log2_64_Ceil(), llvm::report_fatal_error(), llvm::coro::Retcon, llvm::coro::Shape::RetconLowering, llvm::coro::RetconOnce, llvm::coro::Switch, and llvm::coro::Shape::SwitchLowering.
Referenced by llvm::coro::BaseABI::buildCoroutineFrame().
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Definition at line 474 of file CoroFrame.cpp.
References llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::contains(), llvm::find_if(), llvm::findDVRDeclares(), llvm::findDVRDeclareValues(), I, and llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::insert().
Referenced by buildFrameDebugInfo().
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Definition at line 1373 of file CoroFrame.cpp.
References llvm::SmallVectorTemplateCommon< T, typename >::empty(), F, llvm::SmallVectorImpl< T >::pop_back_val(), and llvm::SmallVectorTemplateBase< T, bool >::push_back().
Referenced by llvm::coro::normalizeCoroutine().
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Returns a pointer into the coroutine frame at the offset where Orig is located.
Definition at line 933 of file CoroFrame.cpp.
References assert(), llvm::coro::Shape::CoroBegin, llvm::dyn_cast(), llvm::coro::Shape::FramePtr, llvm::AllocaInst::getAlign(), llvm::Value::getContext(), llvm::Module::getDataLayout(), llvm::Type::getInt64Ty(), llvm::DataLayout::getIntPtrType(), llvm::Instruction::getModule(), llvm::Value::getName(), llvm::AllocaInst::getType(), llvm::Value::getType(), llvm::Offset, and llvm::Align::value().
Referenced by handleAccessBeforeCoroBegin(), and insertSpills().
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Store Def into the coroutine frame.
Definition at line 906 of file CoroFrame.cpp.
References llvm::coro::Shape::CoroBegin, DL, llvm::coro::Shape::FramePtr, G, llvm::Value::getContext(), llvm::Type::getInt64Ty(), llvm::Offset, and Size.
Referenced by insertSpills().
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Definition at line 145 of file CoroFrame.cpp.
References A(), and llvm::dbgs().
Referenced by llvm::coro::BaseABI::buildCoroutineFrame().
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Definition at line 135 of file CoroFrame.cpp.
References llvm::dbgs(), E(), and I.
Referenced by llvm::coro::BaseABI::buildCoroutineFrame().
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Eliminate all problematic uses of swifterror arguments and allocas from the function.
We'll fix them up later when splitting the function.
Definition at line 1703 of file CoroFrame.cpp.
References llvm::dyn_cast(), eliminateSwiftErrorAlloca(), eliminateSwiftErrorArgument(), llvm::SmallVectorTemplateCommon< T, typename >::empty(), F, llvm::AllocaInst::isSwiftError(), llvm::PromoteMemToReg(), llvm::SmallVectorTemplateBase< T, bool >::push_back(), and llvm::AllocaInst::setSwiftError().
Referenced by llvm::coro::normalizeCoroutine().
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Eliminate a formerly-swifterror alloca by inserting the get/set intrinsics and attempting to MemToReg the alloca away.
Definition at line 1639 of file CoroFrame.cpp.
References assert(), Call, llvm::cast(), emitSetAndGetSwiftErrorValueAround(), F, llvm::Use::getUser(), llvm::isa(), llvm::isAllocaPromotable(), llvm::make_early_inc_range(), llvm::Use::set(), and llvm::Value::uses().
Referenced by eliminateSwiftError(), and eliminateSwiftErrorArgument().
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"Eliminate" a swifterror argument by reducing it to the alloca case and then loading and storing in the prologue and epilog.
The argument keeps the swifterror flag.
Definition at line 1665 of file CoroFrame.cpp.
References llvm::cast(), llvm::coro::Shape::CoroEnds, llvm::coro::Shape::CoroSuspends, eliminateSwiftErrorAlloca(), emitSetAndGetSwiftErrorValueAround(), emitSetSwiftErrorValue(), F, llvm::Constant::getNullValue(), llvm::Value::getType(), llvm::PointerType::getUnqual(), llvm::SmallVectorTemplateBase< T, bool >::push_back(), and llvm::Value::replaceAllUsesWith().
Referenced by eliminateSwiftError().
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Get the current swifterror value.
Definition at line 1576 of file CoroFrame.cpp.
References Call, llvm::ConstantPointerNull::get(), llvm::FunctionType::get(), and llvm::coro::Shape::SwiftErrorOps.
Referenced by emitSetAndGetSwiftErrorValueAround().
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Set the swifterror value from the given alloca before a call, then put in back in the alloca afterwards.
Returns an address that will stand in for the swifterror slot until splitting.
Definition at line 1609 of file CoroFrame.cpp.
References Call, llvm::cast(), emitGetSwiftErrorValue(), emitSetSwiftErrorValue(), llvm::AllocaInst::getAllocatedType(), and llvm::isa().
Referenced by eliminateSwiftErrorAlloca(), and eliminateSwiftErrorArgument().
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Set the given value as the current swifterror value.
Returns a slot that can be used as a swifterror slot.
Definition at line 1591 of file CoroFrame.cpp.
References Call, llvm::ConstantPointerNull::get(), llvm::FunctionType::get(), and llvm::coro::Shape::SwiftErrorOps.
Referenced by eliminateSwiftErrorArgument(), and emitSetAndGetSwiftErrorValueAround().
If MaybeArgument is a byval Argument, return its byval type.
Also removes the captures attribute, so that the argument value may be stored directly on the coroutine frame.
Definition at line 895 of file CoroFrame.cpp.
References llvm::dyn_cast().
Referenced by insertSpills().
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Find dbg.declare or dbg.declare_value records referencing Def.
If none are found, walk up the load chain to find one.
Definition at line 967 of file CoroFrame.cpp.
References llvm::cast(), llvm::DbgVariableRecord::Declare, llvm::DbgVariableRecord::DeclareValue, llvm::SmallVectorTemplateCommon< T, typename >::empty(), F, llvm::findDVRDeclares(), llvm::findDVRDeclareValues(), and llvm::isa().
Referenced by insertSpills().
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Definition at line 997 of file CoroFrame.cpp.
References createGEPToFramePointer(), G, llvm::AllocaInst::getAlign(), and Size.
Referenced by insertSpills().
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Definition at line 1028 of file CoroFrame.cpp.
References A(), llvm::coro::Shape::ABI, llvm::coro::Shape::AllocaSpillBlock, llvm::any_of(), assert(), llvm::coro::Async, llvm::BasicBlock::begin(), llvm::CallingConv::C, llvm::cast(), llvm::SmallVectorImpl< T >::clear(), llvm::coro::Shape::CoroBegin, createGEPToFramePointer(), createStoreIntoFrame(), llvm::MDBuilder::createTBAAScalarTypeNode(), llvm::MDBuilder::createTBAAStructTagNode(), llvm::DbgVariableRecord::Declare, llvm::DbgVariableRecord::DeclareValue, llvm::DominatorTree::dominates(), llvm::dyn_cast(), E(), llvm::SmallVectorTemplateCommon< T, typename >::empty(), llvm::Instruction::eraseFromParent(), extractByvalIfArgument(), F, llvm::filterDbgVars(), findDbgRecordsThroughLoads(), llvm::findDbgUsers(), llvm::for_each(), FramePtr, G, GEP, llvm::IntegerType::get(), llvm::ValueAsMetadata::get(), llvm::Value::getContext(), llvm::BasicBlock::getFirstInsertionPt(), llvm::Instruction::getFunction(), llvm::MDNode::getIfExists(), llvm::MDString::getIfExists(), llvm::coro::Shape::getInsertPtAfterFramePtr(), llvm::Value::getName(), llvm::BasicBlock::getParent(), llvm::coro::getSpillInsertionPt(), handleAccessBeforeCoroBegin(), I, llvm::isa(), llvm::make_early_inc_range(), P, llvm::coro::Shape::SwitchLoweringStorage::PromiseAlloca, llvm::SmallVectorTemplateBase< T, bool >::push_back(), llvm::Value::replaceAllUsesWith(), llvm::coro::Retcon, llvm::coro::RetconOnce, llvm::coro::salvageDebugInfo(), llvm::BasicBlock::splitBasicBlock(), llvm::coro::Switch, llvm::coro::Shape::SwitchLowering, llvm::Value::users(), llvm::Value::uses(), and llvm::DbgVariableRecord::Value.
Referenced by llvm::coro::BaseABI::buildCoroutineFrame().
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Definition at line 1520 of file CoroFrame.cpp.
References llvm::dyn_cast(), llvm::Value::users(), and willLeaveFunctionImmediatelyAfter().
Referenced by lowerLocalAllocas().
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Turn each of the given local allocas into a normal (dynamic) alloca instruction.
Definition at line 1538 of file CoroFrame.cpp.
References llvm::cast(), llvm::isa(), localAllocaNeedsStackSave(), llvm::SmallVectorTemplateBase< T, bool >::push_back(), llvm::AllocaInst::setAlignment(), and llvm::Value::users().
Referenced by llvm::coro::BaseABI::buildCoroutineFrame().
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Definition at line 1280 of file CoroFrame.cpp.
References llvm::PHINode::addIncoming(), llvm::BasicBlock::begin(), llvm::cast(), llvm::PHINode::Create(), llvm::dyn_cast(), llvm::BasicBlock::front(), llvm::Value::getName(), and llvm::Instruction::insertBefore().
Referenced by rewritePHIs(), and rewritePHIsForCleanupPad().
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Definition at line 1390 of file CoroFrame.cpp.
References assert(), llvm::PHINode::Create(), llvm::dyn_cast(), llvm::dyn_cast_or_null(), llvm::ehAwareSplitEdge(), llvm::BasicBlock::empty(), llvm::Instruction::eraseFromParent(), llvm::BasicBlock::getFirstNonPHIIt(), llvm::ilist_node_impl< OptionsT >::getIterator(), llvm::Value::getName(), llvm::Value::getType(), llvm::Instruction::insertBefore(), movePHIValuesToInsertedBlock(), llvm::predecessors(), llvm::Value::replaceAllUsesWith(), rewritePHIsForCleanupPad(), and llvm::Value::takeName().
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Definition at line 1466 of file CoroFrame.cpp.
References llvm::dyn_cast(), F, llvm::SmallVectorTemplateBase< T, bool >::push_back(), and rewritePHIs().
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Definition at line 1298 of file CoroFrame.cpp.
References llvm::BasicBlock::Create(), llvm::BasicBlock::getContext(), llvm::Value::getName(), llvm::BasicBlock::getParent(), llvm::Instruction::insertAfter(), movePHIValuesToInsertedBlock(), llvm::pred_size(), llvm::predecessors(), llvm::Instruction::removeFromParent(), llvm::setUnwindEdgeTo(), and llvm::updatePhiNodes().
Referenced by rewritePHIs().
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Definition at line 1818 of file CoroFrame.cpp.
References AbstractManglingParser< Derived, Alloc >::Ops, llvm::DIExpression::appendOpsToArg(), llvm::DIExpression::DerefBefore, llvm::dyn_cast(), llvm::dyn_cast_or_null(), llvm::SmallVectorTemplateCommon< T, typename >::empty(), llvm::DIExpression::EntryValue, F, llvm::DIExpression::foldConstantMath(), llvm::Value::getName(), llvm::DIExpression::getNumLocationOperands(), llvm::Value::getType(), llvm::isa(), llvm::DIExpression::isEntryValue(), llvm::DIExpression::isSingleLocationExpression(), llvm::DIExpression::prepend(), and llvm::salvageDebugInfoImpl().
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For each local variable that all of its user are only used inside one of suspended region, we sink their lifetime.start markers to the place where after the suspend block.
Doing so minimizes the lifetime of each variable, hence minimizing the amount of data we end up putting on the frame.
Definition at line 1738 of file CoroFrame.cpp.
References assert(), llvm::cast(), llvm::coro::Shape::CoroSuspends, llvm::DominatorTree::dominates(), llvm::dyn_cast(), F, llvm::BasicBlock::getParent(), llvm::ilist_detail::node_parent_access< NodeTy, ParentTy >::getParent(), llvm::BasicBlock::getSingleSuccessor(), I, II, llvm::SmallPtrSetImpl< PtrType >::insert(), instructions, llvm::SuspendCrossingInfo::isDefinitionAcrossSuspend(), isLifetimeStart(), llvm::coro::isSuspendBlock(), llvm::SmallVectorTemplateBase< T, bool >::push_back(), llvm::SmallVectorTemplateCommon< T, typename >::size(), and llvm::Value::users().
Referenced by llvm::coro::BaseABI::buildCoroutineFrame().
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Definition at line 532 of file CoroFrame.cpp.
References assert(), llvm::BitWidth, llvm::cast(), llvm::dbgs(), llvm::DataLayout::getABITypeAlign(), llvm::DIType::getAlignInBits(), llvm::StructLayout::getElementOffsetInBits(), llvm::TypeSize::getFixed(), llvm::DIType::getName(), llvm::DataLayout::getPrefTypeAlign(), llvm::DIType::getSizeInBits(), llvm::DataLayout::getStructLayout(), llvm::DataLayout::getTypeSizeInBits(), I, llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::insert(), LLVM_DEBUG, llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::lookup(), Size, solveDIType(), solveTypeName(), and llvm::Align::value().
Referenced by buildFrameDebugInfo(), and solveDIType().
Create name for Type.
It uses MDString to store new created string to avoid memory leak.
Definition at line 494 of file CoroFrame.cpp.
References llvm::cast(), llvm::MDString::get(), llvm::raw_svector_ostream::str(), and llvm::SmallString< InternalLen >::str().
Referenced by solveDIType().
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Definition at line 1493 of file CoroFrame.cpp.
References I, and splitBlockIfNotFirst().
Referenced by llvm::coro::normalizeCoroutine().
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After we split the coroutine, will the given basic block be along an obvious exit path for the resumption function?
Definition at line 1500 of file CoroFrame.cpp.
References llvm::coro::isSuspendBlock(), llvm::successors(), and willLeaveFunctionImmediatelyAfter().
Referenced by localAllocaNeedsStackSave(), and willLeaveFunctionImmediatelyAfter().