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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 StructType * | buildFrameType (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 GEP 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 | 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:
FIXME: If we fill the field SizeInBits with the actual size of __coro_index in bits, then __coro_index wouldn't show in the debugger.
Definition at line 689 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::SwitchFieldIndex::Destroy, 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::coro::Shape::FrameTy, llvm::DICompileUnit::FullDebug, llvm::MDNode::get(), llvm::MDTuple::get(), llvm::ValueAsMetadata::get(), llvm::MDNode::getContext(), llvm::StructType::getElementType(), llvm::DIScope::getFile(), llvm::details::FixedOrScalableQuantity< LeafTy, ValueTy >::getFixedValue(), llvm::coro::Shape::getInsertPtAfterFramePtr(), llvm::DIType::getName(), llvm::StructType::getNumElements(), llvm::DIBuilder::getOrCreateArray(), llvm::DataLayout::getTypeSizeInBits(), llvm::coro::Shape::SwitchLoweringStorage::IndexAlign, llvm::coro::Shape::SwitchLoweringStorage::IndexField, llvm::coro::Shape::SwitchLoweringStorage::IndexOffset, llvm::DenseMapBase< DerivedT, KeyT, ValueT, KeyInfoT, BucketT >::insert(), llvm::dwarf::isCPlusPlus(), llvm::SmallVectorTemplateBase< T, bool >::push_back(), llvm::DIBuilder::replaceArrays(), llvm::MDNode::replaceOperandWith(), llvm::coro::Shape::SwitchFieldIndex::Resume, 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 861 of file CoroFrame.cpp.
References A(), llvm::coro::Shape::ABI, llvm::alignTo(), assert(), llvm::coro::Async, llvm::coro::Shape::AsyncLowering, B(), llvm::CallingConv::C, llvm::coro::Shape::AsyncLoweringStorage::ContextHeaderSize, llvm::coro::Shape::AsyncLoweringStorage::ContextSize, llvm::coro::Shape::CoroSuspends, 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::PointerType::getUnqual(), llvm::coro::Shape::SwitchLoweringStorage::IndexAlign, llvm::coro::Shape::SwitchLoweringStorage::IndexField, llvm::coro::Shape::SwitchLoweringStorage::IndexOffset, 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 544 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 1466 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 GEP into the coroutine frame at the offset where Orig is located.
Definition at line 1015 of file CoroFrame.cpp.
References assert(), llvm::coro::Shape::CoroBegin, llvm::Count, llvm::dyn_cast(), llvm::coro::Shape::FramePtr, llvm::coro::Shape::FrameTy, GEP, llvm::AllocaInst::getAlign(), llvm::AllocaInst::getArraySize(), llvm::Value::getContext(), llvm::Module::getDataLayout(), llvm::Type::getInt32Ty(), llvm::DataLayout::getIntPtrType(), llvm::Instruction::getModule(), llvm::Value::getName(), llvm::AllocaInst::getType(), llvm::Value::getType(), llvm::SmallVectorTemplateBase< T, bool >::push_back(), llvm::report_fatal_error(), and llvm::Align::value().
Referenced by insertSpills().
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Store Def into the coroutine frame.
Definition at line 997 of file CoroFrame.cpp.
References llvm::coro::Shape::FramePtr, llvm::coro::Shape::FrameTy, and G.
Referenced by insertSpills().
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Definition at line 150 of file CoroFrame.cpp.
References A(), and llvm::dbgs().
Referenced by llvm::coro::BaseABI::buildCoroutineFrame().
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Definition at line 140 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 1796 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 1732 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 1758 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 1669 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 1702 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 1684 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 986 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 1064 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 1112 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, llvm::coro::Shape::FrameTy, G, GEP, llvm::IntegerType::get(), llvm::ValueAsMetadata::get(), llvm::AllocaInst::getAllocatedType(), llvm::Value::getContext(), llvm::StructType::getElementType(), 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(), I, llvm::isa(), llvm::AllocaInst::isArrayAllocation(), llvm::make_early_inc_range(), P, llvm::coro::Shape::SwitchLoweringStorage::PromiseAlloca, llvm::SmallVectorTemplateBase< T, bool >::push_back(), llvm::Value::replaceAllUsesWith(), llvm::report_fatal_error(), 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 1613 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 1631 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 1373 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 1483 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 1559 of file CoroFrame.cpp.
References llvm::dyn_cast(), F, llvm::SmallVectorTemplateBase< T, bool >::push_back(), and rewritePHIs().
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Definition at line 1391 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 1911 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 1831 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 602 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 564 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 1586 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 1593 of file CoroFrame.cpp.
References llvm::coro::isSuspendBlock(), llvm::successors(), and willLeaveFunctionImmediatelyAfter().
Referenced by localAllocaNeedsStackSave(), and willLeaveFunctionImmediatelyAfter().