#include "llvm/Transforms/Scalar/RewriteStatepointsForGC.h"
#include "ScalarOptions.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/DenseSet.h"
#include "llvm/ADT/MapVector.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/Sequence.h"
#include "llvm/ADT/SetVector.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/iterator_range.h"
#include "llvm/Analysis/DomTreeUpdater.h"
#include "llvm/Analysis/TargetLibraryInfo.h"
#include "llvm/Analysis/TargetTransformInfo.h"
#include "llvm/IR/Argument.h"
#include "llvm/IR/AttributeMask.h"
#include "llvm/IR/Attributes.h"
#include "llvm/IR/BasicBlock.h"
#include "llvm/IR/CallingConv.h"
#include "llvm/IR/Constant.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/GCStrategy.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/InstIterator.h"
#include "llvm/IR/InstrTypes.h"
#include "llvm/IR/Instruction.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/MDBuilder.h"
#include "llvm/IR/Metadata.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Statepoint.h"
#include "llvm/IR/Type.h"
#include "llvm/IR/User.h"
#include "llvm/IR/Value.h"
#include "llvm/IR/ValueHandle.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/Transforms/Utils/PromoteMemToReg.h"
#include <cassert>
#include <cstddef>
#include <cstdint>
#include <iterator>
#include <optional>
#include <set>
#include <string>
#include <utility>
#include <vector>

Macros
#define	DEBUG_TYPE "rewrite-statepoints-for-gc"

Functions
static void	stripNonValidData (Module &M)
	The IR fed into RewriteStatepointsForGC may have had attributes and metadata implying dereferenceability that are no longer valid/correct after RewriteStatepointsForGC has run.
static std::unique_ptr< GCStrategy >	findGCStrategy (Function &F)
	Looks up the GC strategy for a given function, returning null if the function doesn't have a GC tag.
static bool	shouldRewriteStatepointsIn (Function &F)
	Returns true if this function should be rewritten by this pass.
static ArrayRef< Use >	getDeoptBundleOperands (const ScalarOptions &Opts, const CallBase *Call)
static void	computeLiveInValues (DominatorTree &DT, Function &F, GCPtrLivenessData &Data, GCStrategy *GC)
	Compute the live-in set for every basic block in the function.
static void	findLiveSetAtInst (Instruction inst, GCPtrLivenessData &Data, StatepointLiveSetTy &out, GCStrategy GC)
	Given results from the dataflow liveness computation, find the set of live Values at a particular instruction.
static bool	isGCPointerType (Type T, GCStrategy GC)
static bool	isHandledGCPointerType (Type T, GCStrategy GC)
static bool	containsGCPtrType (Type Ty, GCStrategy GC)
	Returns true if this type contains a gc pointer whether we know how to handle that type or not.
static bool	isUnhandledGCPointerType (Type Ty, GCStrategy GC)
static std::string	suffixed_name_or (Value *V, StringRef Suffix, StringRef DefaultName)
static void	analyzeParsePointLiveness (const ScalarOptions &Opts, DominatorTree &DT, GCPtrLivenessData &OriginalLivenessData, CallBase Call, PartiallyConstructedSafepointRecord &Result, GCStrategy GC)
static bool	isKnownBase (Value *V, const IsKnownBaseMapTy &KnownBases)
	Returns true if V is a known base.
static void	setKnownBase (Value *V, bool IsKnownBase, IsKnownBaseMapTy &KnownBases)
	Caches the IsKnownBase flag for a value and asserts that it wasn't present in the cache before.
static Value *	findBaseDefiningValue (Value *I, DefiningValueMapTy &Cache, IsKnownBaseMapTy &KnownBases)
	Helper function for findBasePointer - Will return a value which either a) defines the base pointer for the input, b) blocks the simple search (i.e.
static Value *	findBaseDefiningValueOfVector (Value *I, DefiningValueMapTy &Cache, IsKnownBaseMapTy &KnownBases)
	Return a base defining value for the 'Index' element of the given vector instruction 'I'.
static Value *	findBaseDefiningValueCached (Value *I, DefiningValueMapTy &Cache, IsKnownBaseMapTy &KnownBases)
	Returns the base defining value for this value.
static Value *	findBaseOrBDV (Value *I, DefiningValueMapTy &Cache, IsKnownBaseMapTy &KnownBases)
	Return a base pointer for this value if known.
static bool	isOriginalBaseResult (Value *V)
	This value is a base pointer that is not generated by RS4GC, i.e.
static bool	areBothVectorOrScalar (Value First, Value Second)
static raw_ostream &	operator<< (raw_ostream &OS, const BDVState &State)
static Value *	findBasePointer (Value *I, DefiningValueMapTy &Cache, IsKnownBaseMapTy &KnownBases)
	For a given value or instruction, figure out what base ptr its derived from.
static void	findBasePointers (const StatepointLiveSetTy &live, PointerToBaseTy &PointerToBase, DominatorTree *DT, DefiningValueMapTy &DVCache, IsKnownBaseMapTy &KnownBases)
static void	findBasePointers (DominatorTree &DT, DefiningValueMapTy &DVCache, CallBase *Call, PartiallyConstructedSafepointRecord &result, PointerToBaseTy &PointerToBase, IsKnownBaseMapTy &KnownBases)
	Find the required based pointers (and adjust the live set) for the given parse point.
static void	recomputeLiveInValues (GCPtrLivenessData &RevisedLivenessData, CallBase Call, PartiallyConstructedSafepointRecord &result, PointerToBaseTy &PointerToBase, GCStrategy GC)
	Given an updated version of the dataflow liveness results, update the liveset and base pointer maps for the call site CS.
static void	recomputeLiveInValues (Function &F, DominatorTree &DT, ArrayRef< CallBase * > toUpdate, MutableArrayRef< struct PartiallyConstructedSafepointRecord > records, PointerToBaseTy &PointerToBase, GCStrategy *GC)
static Instruction *	rematerializeChain (ArrayRef< Instruction * > ChainToBase, BasicBlock::iterator InsertBefore, Value RootOfChain, Value AlternateLiveBase)
static BasicBlock *	normalizeForInvokeSafepoint (BasicBlock BB, BasicBlock InvokeParent, DominatorTree &DT)
static AttributeList	legalizeCallAttributes (CallBase *Call, bool IsMemIntrinsic, AttributeList StatepointAL)
static void	CreateGCRelocates (ArrayRef< Value * > LiveVariables, ArrayRef< Value * > BasePtrs, Instruction StatepointToken, IRBuilder<> &Builder, GCStrategy GC)
	Helper function to place all gc relocates necessary for the given statepoint.
static StringRef	getDeoptLowering (CallBase *Call)
static void	makeStatepointExplicitImpl (CallBase Call, const SmallVectorImpl< Value > &BasePtrs, const SmallVectorImpl< Value * > &LiveVariables, PartiallyConstructedSafepointRecord &Result, std::vector< DeferredReplacement > &Replacements, const PointerToBaseTy &PointerToBase, GCStrategy *GC)
static void	makeStatepointExplicit (DominatorTree &DT, CallBase Call, PartiallyConstructedSafepointRecord &Result, std::vector< DeferredReplacement > &Replacements, const PointerToBaseTy &PointerToBase, GCStrategy GC)
static void	insertRelocationStores (iterator_range< Instruction::user_iterator > GCRelocs, DenseMap< Value , AllocaInst > &AllocaMap, DenseSet< Value * > &VisitedLiveValues)
static void	insertRematerializationStores (const RematerializedValueMapTy &RematerializedValues, DenseMap< Value , AllocaInst > &AllocaMap, DenseSet< Value * > &VisitedLiveValues)
static void	relocationViaAlloca (Function &F, DominatorTree &DT, ArrayRef< Value * > Live, ArrayRef< PartiallyConstructedSafepointRecord > Records)
	Do all the relocation update via allocas and mem2reg.
static void	insertUseHolderAfter (CallBase Call, const ArrayRef< Value > Values, SmallVectorImpl< CallInst * > &Holders)
	Insert holders so that each Value is obviously live through the entire lifetime of the call.
static void	findLiveReferences (const ScalarOptions &Opts, Function &F, DominatorTree &DT, ArrayRef< CallBase * > toUpdate, MutableArrayRef< struct PartiallyConstructedSafepointRecord > records, GCStrategy *GC)
static Value *	findRematerializableChainToBasePointer (SmallVectorImpl< Instruction * > &ChainToBase, Value *CurrentValue)
static InstructionCost	chainToBasePointerCost (SmallVectorImpl< Instruction * > &Chain, TargetTransformInfo &TTI)
static bool	AreEquivalentPhiNodes (PHINode &OrigRootPhi, PHINode &AlternateRootPhi)
static void	findRematerializationCandidates (PointerToBaseTy PointerToBase, RematCandTy &RematerizationCandidates, TargetTransformInfo &TTI)
static void	rematerializeLiveValuesAtUses (const ScalarOptions &Opts, RematCandTy &RematerizationCandidates, MutableArrayRef< PartiallyConstructedSafepointRecord > Records, PointerToBaseTy &PointerToBase)
static void	rematerializeLiveValues (const ScalarOptions &Opts, CallBase *Call, PartiallyConstructedSafepointRecord &Info, PointerToBaseTy &PointerToBase, RematCandTy &RematerizationCandidates, TargetTransformInfo &TTI)
static bool	inlineGetBaseAndOffset (Function &F, SmallVectorImpl< CallInst * > &Intrinsics, DefiningValueMapTy &DVCache, IsKnownBaseMapTy &KnownBases)
static bool	insertParsePoints (const ScalarOptions &Opts, Function &F, DominatorTree &DT, TargetTransformInfo &TTI, SmallVectorImpl< CallBase * > &ToUpdate, DefiningValueMapTy &DVCache, IsKnownBaseMapTy &KnownBases)
static AttributeMask	getParamAndReturnAttributesToRemove ()
static void	stripNonValidAttributesFromPrototype (Function &F)
static void	stripInvalidMetadataFromInstruction (Instruction &I)
	Certain metadata on instructions are invalid after running RS4GC.
static void	stripNonValidDataFromBody (Function &F)
static void	computeLiveInValues (BasicBlock::reverse_iterator Begin, BasicBlock::reverse_iterator End, SetVector< Value * > &LiveTmp, GCStrategy *GC)
	Compute the live-in set for the location rbegin starting from the live-out set of the basic block.
static void	computeLiveOutSeed (BasicBlock BB, SetVector< Value > &LiveTmp, GCStrategy *GC)
static SetVector< Value * >	computeKillSet (BasicBlock BB, GCStrategy GC)
static void	checkBasicSSA (DominatorTree &DT, SetVector< Value * > &Live, Instruction *TI, bool TermOkay=false)
	Check that the items in 'Live' dominate 'TI'.
static void	checkBasicSSA (DominatorTree &DT, GCPtrLivenessData &Data, BasicBlock &BB)
	Check that all the liveness sets used during the computation of liveness obey basic SSA properties.

Variables
static bool	ClobberNonLive = false
static cl::opt< bool, true >	ClobberNonLiveOverride ("rs4gc-clobber-non-live", cl::location(ClobberNonLive), cl::Hidden)
static constexpr Attribute::AttrKind	FnAttrsToStrip []

Macro Definition Documentation

◆ DEBUG_TYPE

#define DEBUG_TYPE "rewrite-statepoints-for-gc"

Definition at line 77 of file RewriteStatepointsForGC.cpp.

Function Documentation

◆ analyzeParsePointLiveness()

void analyzeParsePointLiveness	(	const ScalarOptions &	Opts,
		DominatorTree &	DT,
		GCPtrLivenessData &	OriginalLivenessData,
		CallBase *	Call,
		PartiallyConstructedSafepointRecord &	Result,
		GCStrategy *	GC )

static

Definition at line 292 of file RewriteStatepointsForGC.cpp.

References Call, llvm::dbgs(), and findLiveSetAtInst().

Referenced by findLiveReferences().

◆ areBothVectorOrScalar()

bool areBothVectorOrScalar	(	Value *	First,
		Value *	Second )

static

Definition at line 667 of file RewriteStatepointsForGC.cpp.

References llvm::First, llvm::Value::getType(), and llvm::isa().

Referenced by findBasePointer().

◆ AreEquivalentPhiNodes()

bool AreEquivalentPhiNodes	(	PHINode &	OrigRootPhi,
		PHINode &	AlternateRootPhi )

static

Definition at line 2305 of file RewriteStatepointsForGC.cpp.

References llvm::DenseMapBase< StorageT, KeyT, ValueT, KeyInfoT, BucketT >::end(), llvm::DenseMapBase< StorageT, KeyT, ValueT, KeyInfoT, BucketT >::find(), llvm::PHINode::getIncomingBlock(), llvm::PHINode::getIncomingValue(), llvm::PHINode::getNumIncomingValues(), and llvm::ilist_detail::node_parent_access< NodeTy, ParentTy >::getParent().

Referenced by findRematerializationCandidates().

◆ chainToBasePointerCost()

InstructionCost chainToBasePointerCost	(	SmallVectorImpl< Instruction * > &	Chain,
		TargetTransformInfo &	TTI )

static

Definition at line 2271 of file RewriteStatepointsForGC.cpp.

References assert(), llvm::dyn_cast(), GEP, llvm::TargetTransformInfo::getCastContextHint(), llvm_unreachable, and llvm::TargetTransformInfo::TCK_SizeAndLatency.

Referenced by findRematerializationCandidates().

◆ checkBasicSSA() [1/2]

void checkBasicSSA	(	DominatorTree &	DT,
		GCPtrLivenessData &	Data,
		BasicBlock &	BB )

static

Check that all the liveness sets used during the computation of liveness obey basic SSA properties.

This is useful for finding cases where we miss a def.

Definition at line 3251 of file RewriteStatepointsForGC.cpp.

References checkBasicSSA(), llvm::Data, and llvm::BasicBlock::getTerminator().

◆ checkBasicSSA() [2/2]

void checkBasicSSA	(	DominatorTree &	DT,
		SetVector< Value * > &	Live,
		Instruction *	TI,
		bool	TermOkay = false )

static

Check that the items in 'Live' dominate 'TI'.

This is used as a basic validation check for the liveness computation.

Definition at line 3233 of file RewriteStatepointsForGC.cpp.

References assert(), llvm::DominatorTree::dominates(), llvm::dyn_cast(), and I.

Referenced by checkBasicSSA(), and computeLiveInValues().

◆ computeKillSet()

SetVector< Value * > computeKillSet	(	BasicBlock *	BB,
		GCStrategy *	GC )

static

Definition at line 3222 of file RewriteStatepointsForGC.cpp.

References I, llvm::SetVector< T, Vector, Set, N >::insert(), and isHandledGCPointerType().

Referenced by computeLiveInValues().

◆ computeLiveInValues() [1/2]

void computeLiveInValues	(	BasicBlock::reverse_iterator	Begin,
		BasicBlock::reverse_iterator	End,
		SetVector< Value * > &	LiveTmp,
		GCStrategy *	GC )

static

Compute the live-in set for the location rbegin starting from the live-out set of the basic block.

Definition at line 3172 of file RewriteStatepointsForGC.cpp.

References assert(), llvm::End, I, llvm::SetVector< T, Vector, Set, N >::insert(), llvm::isa(), isHandledGCPointerType(), isUnhandledGCPointerType(), llvm::make_range(), and llvm::SetVector< T, Vector, Set, N >::remove().

◆ computeLiveInValues() [2/2]

void computeLiveInValues	(	DominatorTree &	DT,
		Function &	F,
		GCPtrLivenessData &	Data,
		GCStrategy *	GC )

static

Compute the live-in set for every basic block in the function.

Definition at line 3259 of file RewriteStatepointsForGC.cpp.

References assert(), checkBasicSSA(), computeKillSet(), computeLiveInValues(), computeLiveOutSeed(), llvm::Data, llvm::SetVector< T, Vector, Set, N >::empty(), F, llvm::SetVector< T, Vector, Set, N >::insert_range(), llvm::Kill, llvm::SetVector< T, Vector, Set, N >::pop_back_val(), llvm::predecessors(), llvm::SetVector< T, Vector, Set, N >::set_subtract(), llvm::SetVector< T, Vector, Set, N >::set_union(), llvm::SetVector< T, Vector, Set, N >::size(), and llvm::successors().

Referenced by computeLiveInValues(), findLiveReferences(), findLiveSetAtInst(), and recomputeLiveInValues().

◆ computeLiveOutSeed()

void computeLiveOutSeed	(	BasicBlock *	BB,
		SetVector< Value * > &	LiveTmp,
		GCStrategy *	GC )

static

Definition at line 3205 of file RewriteStatepointsForGC.cpp.

References assert(), llvm::dyn_cast(), llvm::PHINode::getIncomingValueForBlock(), I, llvm::SetVector< T, Vector, Set, N >::insert(), llvm::isa(), isHandledGCPointerType(), isUnhandledGCPointerType(), and llvm::successors().

Referenced by computeLiveInValues().

◆ containsGCPtrType()

bool containsGCPtrType	(	Type *	Ty,
		GCStrategy *	GC )

static

Returns true if this type contains a gc pointer whether we know how to handle that type or not.

Definition at line 260 of file RewriteStatepointsForGC.cpp.

References llvm::any_of(), containsGCPtrType(), llvm::dyn_cast(), and isGCPointerType().

◆ CreateGCRelocates()

void CreateGCRelocates	(	ArrayRef< Value * >	LiveVariables,
		ArrayRef< Value * >	BasePtrs,
		Instruction *	StatepointToken,
		IRBuilder<> &	Builder,
		GCStrategy *	GC )

static

Helper function to place all gc relocates necessary for the given statepoint.

Inputs: liveVariables - list of variables to be relocated. basePtrs - base pointers. statepointToken - statepoint instruction to which relocates should be bound. Builder - Llvm IR builder to be used to construct new calls.

Definition at line 1482 of file RewriteStatepointsForGC.cpp.

References assert(), llvm::ArrayRef< T >::begin(), llvm::cast(), llvm::CallingConv::Cold, llvm::dyn_cast(), llvm::ArrayRef< T >::end(), llvm::find(), llvm::FixedVectorType::get(), llvm::PointerType::get(), llvm::Instruction::getModule(), llvm::Intrinsic::getOrInsertDeclaration(), isHandledGCPointerType(), llvm::ArrayRef< T >::size(), suffixed_name_or(), and llvm::DenseMapBase< StorageT, KeyT, ValueT, KeyInfoT, BucketT >::try_emplace().

Referenced by makeStatepointExplicitImpl().

◆ findBaseDefiningValue()

Value * findBaseDefiningValue	(	Value *	I,
		DefiningValueMapTy &	Cache,
		IsKnownBaseMapTy &	KnownBases )

static

Helper function for findBasePointer - Will return a value which either a) defines the base pointer for the input, b) blocks the simple search (i.e.

a PHI or Select of two derived pointers), or c) involves a change from pointer to vector type or back.

Definition at line 429 of file RewriteStatepointsForGC.cpp.

References assert(), llvm::cast(), llvm::dyn_cast(), findBaseDefiningValue(), findBaseDefiningValueOfVector(), GEP, llvm::ConstantPointerNull::get(), I, II, llvm::isa(), llvm_unreachable, setKnownBase(), and llvm::AtomicRMWInst::Xchg.

Referenced by findBaseDefiningValue(), findBaseDefiningValueCached(), and findBaseDefiningValueOfVector().

◆ findBaseDefiningValueCached()

Value * findBaseDefiningValueCached	(	Value *	I,
		DefiningValueMapTy &	Cache,
		IsKnownBaseMapTy &	KnownBases )

static

Returns the base defining value for this value.

Definition at line 610 of file RewriteStatepointsForGC.cpp.

References assert(), llvm::dbgs(), findBaseDefiningValue(), I, and LLVM_DEBUG.

Referenced by findBaseOrBDV().

◆ findBaseDefiningValueOfVector()

Value * findBaseDefiningValueOfVector	(	Value *	I,
		DefiningValueMapTy &	Cache,
		IsKnownBaseMapTy &	KnownBases )

static

Return a base defining value for the 'Index' element of the given vector instruction 'I'.

If Index is null, returns a BDV for the entire vector 'I'. As an optimization, this method will try to determine when the element is known to already be a base pointer. If this can be established, the second value in the returned pair will be true. Note that either a vector or a pointer typed value can be returned. For the former, the vector returned is a BDV (and possibly a base) of the entire vector 'I'. If the later, the return pointer is a BDV (or possibly a base) for the particular element in 'I'.

Definition at line 331 of file RewriteStatepointsForGC.cpp.

References assert(), llvm::dyn_cast(), findBaseDefiningValue(), GEP, llvm::ConstantAggregateZero::get(), I, llvm::isa(), and setKnownBase().

Referenced by findBaseDefiningValue().

◆ findBaseOrBDV()

Value * findBaseOrBDV	(	Value *	I,
		DefiningValueMapTy &	Cache,
		IsKnownBaseMapTy &	KnownBases )

static

Return a base pointer for this value if known.

Otherwise, return it's base defining value.

Definition at line 627 of file RewriteStatepointsForGC.cpp.

References findBaseDefiningValueCached(), and I.

Referenced by findBasePointer().

◆ findBasePointer()

Value * findBasePointer	(	Value *	I,
		DefiningValueMapTy &	Cache,
		IsKnownBaseMapTy &	KnownBases )

static

For a given value or instruction, figure out what base ptr its derived from.

For gc objects, this is simply itself. On success, returns a value which is the base pointer. (This is reliable and can be used for relocation.) On failure, returns nullptr.

Definition at line 791 of file RewriteStatepointsForGC.cpp.

References areBothVectorOrScalar(), assert(), llvm::sampleprof::Base, llvm::cast(), llvm::MapVector< KeyT, ValueT, MapType, VectorType, N >::count(), llvm::dbgs(), DL, llvm::dyn_cast(), llvm::SmallVectorTemplateCommon< T, typename >::empty(), llvm::MapVector< KeyT, ValueT, MapType, VectorType, N >::end(), F, llvm::MapVector< KeyT, ValueT, MapType, VectorType, N >::find(), findBaseOrBDV(), llvm::MDNode::get(), llvm::PoisonValue::get(), llvm::PHINode::getIncomingBlock(), llvm::PHINode::getIncomingValue(), llvm::Value::getName(), llvm::PHINode::getNumIncomingValues(), llvm::BasicBlock::getTerminator(), llvm::Value::getType(), I, llvm::MapVector< KeyT, ValueT, MapType, VectorType, N >::insert(), llvm::Instruction::insertBefore(), llvm::isa(), isKnownBase(), isOriginalBaseResult(), LLVM_DEBUG, llvm_unreachable, llvm::SmallVectorImpl< T >::pop_back_val(), llvm::SmallVectorTemplateBase< T, bool >::push_back(), setKnownBase(), llvm::Instruction::setMetadata(), llvm::Value::setName(), llvm::MapVector< KeyT, ValueT, MapType, VectorType, N >::size(), suffixed_name_or(), ToRemove, and llvm::DenseMapBase< StorageT, KeyT, ValueT, KeyInfoT, BucketT >::try_emplace().

Referenced by findBasePointers(), and inlineGetBaseAndOffset().

◆ findBasePointers() [1/2]

void findBasePointers	(	const StatepointLiveSetTy &	live,
		PointerToBaseTy &	PointerToBase,
		DominatorTree *	DT,
		DefiningValueMapTy &	DVCache,
		IsKnownBaseMapTy &	KnownBases )

static

Definition at line 1287 of file RewriteStatepointsForGC.cpp.

References assert(), llvm::cast(), llvm::DominatorTree::dominates(), findBasePointer(), and llvm::isa().

Referenced by findBasePointers(), and insertParsePoints().

◆ findBasePointers() [2/2]

void findBasePointers	(	DominatorTree &	DT,
		DefiningValueMapTy &	DVCache,
		CallBase *	Call,
		PartiallyConstructedSafepointRecord &	result,
		PointerToBaseTy &	PointerToBase,
		IsKnownBaseMapTy &	KnownBases )

static

Find the required based pointers (and adjust the live set) for the given parse point.

Definition at line 1304 of file RewriteStatepointsForGC.cpp.

References Call, findBasePointers(), and llvm::LLVMContext::OB_deopt.

◆ findGCStrategy()

std::unique_ptr< GCStrategy > findGCStrategy ( Function & F )

static

Looks up the GC strategy for a given function, returning null if the function doesn't have a GC tag.

The strategy is stored in the cache.

Definition at line 2977 of file RewriteStatepointsForGC.cpp.

References F, and llvm::getGCStrategy().

Referenced by insertParsePoints(), and shouldRewriteStatepointsIn().

◆ findLiveReferences()

void findLiveReferences	(	const ScalarOptions &	Opts,
		Function &	F,
		DominatorTree &	DT,
		ArrayRef< CallBase * >	toUpdate,
		MutableArrayRef< struct PartiallyConstructedSafepointRecord >	records,
		GCStrategy *	GC )

static

Definition at line 2225 of file RewriteStatepointsForGC.cpp.

References analyzeParsePointLiveness(), computeLiveInValues(), F, info, and llvm::ArrayRef< T >::size().

Referenced by insertParsePoints().

◆ findLiveSetAtInst()

void findLiveSetAtInst	(	Instruction *	inst,
		GCPtrLivenessData &	Data,
		StatepointLiveSetTy &	out,
		GCStrategy *	GC )

static

Given results from the dataflow liveness computation, find the set of live Values at a particular instruction.

Definition at line 3326 of file RewriteStatepointsForGC.cpp.

References assert(), computeLiveInValues(), llvm::Data, llvm::ilist_node_impl< OptionsT >::getIterator(), llvm::ilist_detail::node_parent_access< NodeTy, ParentTy >::getParent(), llvm::BasicBlock::rbegin(), and llvm::SetVector< T, Vector, Set, N >::remove().

Referenced by analyzeParsePointLiveness(), and recomputeLiveInValues().

◆ findRematerializableChainToBasePointer()

Value * findRematerializableChainToBasePointer	(	SmallVectorImpl< Instruction * > &	ChainToBase,
		Value *	CurrentValue )

static

Definition at line 2245 of file RewriteStatepointsForGC.cpp.

References llvm::dyn_cast(), findRematerializableChainToBasePointer(), GEP, and llvm::SmallVectorTemplateBase< T, bool >::push_back().

Referenced by findRematerializableChainToBasePointer(), findRematerializationCandidates(), and rematerializeLiveValuesAtUses().

◆ findRematerializationCandidates()

void findRematerializationCandidates	(	PointerToBaseTy	PointerToBase,
		RematCandTy &	RematerizationCandidates,
		TargetTransformInfo &	TTI )

static

Definition at line 2334 of file RewriteStatepointsForGC.cpp.

References AreEquivalentPhiNodes(), llvm::sampleprof::Base, chainToBasePointerCost(), llvm::dyn_cast(), findRematerializableChainToBasePointer(), and llvm::SmallVectorTemplateCommon< T, typename >::size().

Referenced by insertParsePoints().

◆ getDeoptBundleOperands()

ArrayRef< Use > getDeoptBundleOperands	(	const ScalarOptions &	Opts,
		const CallBase *	Call )

static

Definition at line 208 of file RewriteStatepointsForGC.cpp.

References assert(), Call, and llvm::LLVMContext::OB_deopt.

Referenced by insertParsePoints().

◆ getDeoptLowering()

StringRef getDeoptLowering ( CallBase * Call )

static

Definition at line 1611 of file RewriteStatepointsForGC.cpp.

References assert(), Call, and F.

Referenced by makeStatepointExplicitImpl().

◆ getParamAndReturnAttributesToRemove()

AttributeMask getParamAndReturnAttributesToRemove ( )

static

Definition at line 2859 of file RewriteStatepointsForGC.cpp.

Referenced by stripNonValidAttributesFromPrototype(), and stripNonValidDataFromBody().

◆ inlineGetBaseAndOffset()

bool inlineGetBaseAndOffset	(	Function &	F,
		SmallVectorImpl< CallInst * > &	Intrinsics,
		DefiningValueMapTy &	DVCache,
		IsKnownBaseMapTy &	KnownBases )

static

Definition at line 2582 of file RewriteStatepointsForGC.cpp.

References assert(), llvm::sampleprof::Base, Changed, DL, F, findBasePointer(), llvm::Type::getIntNTy(), llvm::Type::getPointerAddressSpace(), llvm::Value::getType(), llvm_unreachable, llvm::Offset, and suffixed_name_or().

Referenced by llvm::RewriteStatepointsForGC::runOnFunction().

◆ insertParsePoints()

bool insertParsePoints	(	const ScalarOptions &	Opts,
		Function &	F,
		DominatorTree &	DT,
		TargetTransformInfo &	TTI,
		SmallVectorImpl< CallBase * > &	ToUpdate,
		DefiningValueMapTy &	DVCache,
		IsKnownBaseMapTy &	KnownBases )

static

Global mapping from live pointers to a base-defining-value.

Definition at line 2630 of file RewriteStatepointsForGC.cpp.

References assert(), llvm::SmallVectorTemplateCommon< T, typename >::begin(), Call, llvm::cast(), llvm::SmallVectorImpl< T >::clear(), llvm::DominatorTree::dominates(), llvm::SmallVectorTemplateCommon< T, typename >::empty(), llvm::SmallVectorTemplateCommon< T, typename >::end(), llvm::errs(), F, findBasePointers(), findGCStrategy(), findLiveReferences(), findRematerializationCandidates(), llvm::SetVector< T, Vector, Set, N >::getArrayRef(), getDeoptBundleOperands(), II, info, llvm::SetVector< T, Vector, Set, N >::insert_range(), insertUseHolderAfter(), llvm::isa(), isHandledGCPointerType(), llvm::DominatorTree::isReachableFromEntry(), isUnhandledGCPointerType(), llvm::make_isa_range(), makeStatepointExplicit(), normalizeForInvokeSafepoint(), llvm::SmallVectorTemplateBase< T, bool >::push_back(), recomputeLiveInValues(), relocationViaAlloca(), rematerializeLiveValues(), rematerializeLiveValuesAtUses(), llvm::SmallVectorImpl< T >::reserve(), and llvm::SmallVectorTemplateCommon< T, typename >::size().

Referenced by llvm::RewriteStatepointsForGC::runOnFunction().

◆ insertRelocationStores()

void insertRelocationStores	(	iterator_range< Instruction::user_iterator >	GCRelocs,
		DenseMap< Value , AllocaInst > &	AllocaMap,
		DenseSet< Value * > &	VisitedLiveValues )

static

Definition at line 1950 of file RewriteStatepointsForGC.cpp.

References assert(), llvm::DenseMapBase< StorageT, KeyT, ValueT, KeyInfoT, BucketT >::count(), llvm::dyn_cast(), llvm::GCRelocateInst::getDerivedPtr(), llvm::ilist_node_impl< OptionsT >::getIterator(), llvm::ilist_node_with_parent< NodeTy, ParentTy, Options >::getNextNode(), and llvm::detail::DenseSetImpl< ValueT, MapTy >::insert().

Referenced by relocationViaAlloca().

◆ insertRematerializationStores()

void insertRematerializationStores	(	const RematerializedValueMapTy &	RematerializedValues,
		DenseMap< Value , AllocaInst > &	AllocaMap,
		DenseSet< Value * > &	VisitedLiveValues )

static

Definition at line 1975 of file RewriteStatepointsForGC.cpp.

References assert(), llvm::DenseMapBase< StorageT, KeyT, ValueT, KeyInfoT, BucketT >::count(), llvm::ilist_node_impl< OptionsT >::getIterator(), and llvm::detail::DenseSetImpl< ValueT, MapTy >::insert().

Referenced by relocationViaAlloca().

◆ insertUseHolderAfter()

void insertUseHolderAfter	(	CallBase *	Call,
		const ArrayRef< Value * >	Values,
		SmallVectorImpl< CallInst * > &	Holders )

static

Insert holders so that each Value is obviously live through the entire lifetime of the call.

Definition at line 2200 of file RewriteStatepointsForGC.cpp.

References Call, llvm::cast(), llvm::CallInst::Create(), llvm::FunctionType::get(), llvm::Type::getVoidTy(), II, llvm::isa(), llvm::SmallVectorTemplateBase< T, bool >::push_back(), and llvm::Values.

Referenced by insertParsePoints().

◆ isGCPointerType()

bool isGCPointerType	(	Type *	T,
		GCStrategy *	GC )

static

Definition at line 231 of file RewriteStatepointsForGC.cpp.

References assert(), llvm::isa(), and T.

◆ isHandledGCPointerType()

bool isHandledGCPointerType	(	Type *	T,
		GCStrategy *	GC )

static

Definition at line 245 of file RewriteStatepointsForGC.cpp.

References llvm::dyn_cast(), isGCPointerType(), and T.

Referenced by computeKillSet(), computeLiveInValues(), computeLiveOutSeed(), CreateGCRelocates(), insertParsePoints(), and isUnhandledGCPointerType().

◆ isKnownBase()

bool isKnownBase	(	Value *	V,
		const IsKnownBaseMapTy &	KnownBases )

static

Returns true if V is a known base.

Definition at line 650 of file RewriteStatepointsForGC.cpp.

References assert().

Referenced by findBasePointer().

◆ isOriginalBaseResult()

bool isOriginalBaseResult ( Value * V )

static

This value is a base pointer that is not generated by RS4GC, i.e.

it already exists in the code.

Definition at line 642 of file RewriteStatepointsForGC.cpp.

References llvm::isa().

Referenced by findBasePointer().

◆ isUnhandledGCPointerType()

bool isUnhandledGCPointerType	(	Type *	Ty,
		GCStrategy *	GC )

static

Definition at line 276 of file RewriteStatepointsForGC.cpp.

References containsGCPtrType(), and isHandledGCPointerType().

Referenced by computeLiveInValues(), computeLiveOutSeed(), and insertParsePoints().

◆ legalizeCallAttributes()

AttributeList legalizeCallAttributes	(	CallBase *	Call,
		bool	IsMemIntrinsic,
		AttributeList	StatepointAL )

static

Definition at line 1437 of file RewriteStatepointsForGC.cpp.

References A(), Call, llvm::GCStatepointInst::CallArgsBeginPos, FnAttrsToStrip, I, llvm::isStatepointDirectiveAttr(), and llvm::seq().

Referenced by makeStatepointExplicitImpl().

◆ makeStatepointExplicit()

void makeStatepointExplicit	(	DominatorTree &	DT,
		CallBase *	Call,
		PartiallyConstructedSafepointRecord &	Result,
		std::vector< DeferredReplacement > &	Replacements,
		const PointerToBaseTy &	PointerToBase,
		GCStrategy *	GC )

static

Definition at line 1920 of file RewriteStatepointsForGC.cpp.

References assert(), llvm::sampleprof::Base, Call, makeStatepointExplicitImpl(), llvm::SmallVectorTemplateBase< T, bool >::push_back(), llvm::SmallVectorImpl< T >::reserve(), and llvm::SmallVectorTemplateCommon< T, typename >::size().

Referenced by insertParsePoints().

◆ makeStatepointExplicitImpl()

void makeStatepointExplicitImpl	(	CallBase *	Call,
		const SmallVectorImpl< Value * > &	BasePtrs,
		const SmallVectorImpl< Value * > &	LiveVariables,
		PartiallyConstructedSafepointRecord &	Result,
		std::vector< DeferredReplacement > &	Replacements,
		const PointerToBaseTy &	PointerToBase,
		GCStrategy *	GC )

static

Definition at line 1627 of file RewriteStatepointsForGC.cpp.

References assert(), llvm::sampleprof::Base, llvm::BasicBlock::begin(), Call, llvm::cast(), llvm::SmallVectorImpl< T >::clear(), CreateGCRelocates(), llvm::StatepointDirectives::DefaultStatepointID, llvm::DeoptLiveIn, DL, llvm::dyn_cast(), F, llvm::GCTransition, llvm::ConstantPointerNull::get(), llvm::FunctionType::get(), llvm::CallBase::getAttributes(), llvm::FunctionCallee::getCallee(), llvm::Value::getContext(), getDeoptLowering(), llvm::BasicBlock::getFirstInsertionPt(), llvm::Type::getIntNTy(), llvm::BasicBlock::getLandingPadInst(), llvm::BasicBlock::getUniquePredecessor(), llvm::Type::getVoidTy(), II, llvm::isa(), legalizeCallAttributes(), llvm_unreachable, llvm::None, llvm::StatepointDirectives::NumPatchBytes, llvm::LLVMContext::OB_deopt, llvm::LLVMContext::OB_gc_transition, llvm::parseStatepointDirectivesFromAttrs(), llvm::SmallVectorTemplateBase< T, bool >::push_back(), llvm::CallBase::setAttributes(), llvm::CallBase::setCallingConv(), llvm::Value::setName(), llvm::CallInst::setTailCallKind(), llvm::SmallVectorTemplateCommon< T, typename >::size(), llvm::StatepointDirectives::StatepointID, and uint64_t.

Referenced by makeStatepointExplicit().

◆ normalizeForInvokeSafepoint()

BasicBlock * normalizeForInvokeSafepoint	(	BasicBlock *	BB,
		BasicBlock *	InvokeParent,
		DominatorTree &	DT )

static

Definition at line 1410 of file RewriteStatepointsForGC.cpp.

References assert(), llvm::BasicBlock::begin(), llvm::FoldSingleEntryPHINodes(), llvm::BasicBlock::getUniquePredecessor(), llvm::isa(), and llvm::SplitBlockPredecessors().

Referenced by insertParsePoints().

◆ operator<<()

raw_ostream & operator<<	(	raw_ostream &	OS,
		const BDVState &	State )

static

Definition at line 781 of file RewriteStatepointsForGC.cpp.

◆ recomputeLiveInValues() [1/2]

void recomputeLiveInValues	(	Function &	F,
		DominatorTree &	DT,
		ArrayRef< CallBase * >	toUpdate,
		MutableArrayRef< struct PartiallyConstructedSafepointRecord >	records,
		PointerToBaseTy &	PointerToBase,
		GCStrategy *	GC )

static

Definition at line 1334 of file RewriteStatepointsForGC.cpp.

References computeLiveInValues(), F, info, recomputeLiveInValues(), and llvm::ArrayRef< T >::size().

◆ recomputeLiveInValues() [2/2]

void recomputeLiveInValues	(	GCPtrLivenessData &	RevisedLivenessData,
		CallBase *	Call,
		PartiallyConstructedSafepointRecord &	result,
		PointerToBaseTy &	PointerToBase,
		GCStrategy *	GC )

static

Given an updated version of the dataflow liveness results, update the liveset and base pointer maps for the call site CS.

Definition at line 3344 of file RewriteStatepointsForGC.cpp.

References Call, and findLiveSetAtInst().

Referenced by insertParsePoints(), and recomputeLiveInValues().

◆ relocationViaAlloca()

void relocationViaAlloca	(	Function &	F,
		DominatorTree &	DT,
		ArrayRef< Value * >	Live,
		ArrayRef< PartiallyConstructedSafepointRecord >	Records )

static

Do all the relocation update via allocas and mem2reg.

Definition at line 1997 of file RewriteStatepointsForGC.cpp.

References assert(), llvm::cast(), ClobberNonLive, llvm::DenseMapBase< StorageT, KeyT, ValueT, KeyInfoT, BucketT >::contains(), llvm::detail::DenseSetImpl< ValueT, MapTy >::count(), DL, llvm::dyn_cast(), llvm::SmallVectorTemplateCommon< T, typename >::empty(), F, llvm::ConstantAggregateZero::get(), llvm::ConstantPointerNull::get(), llvm::BasicBlock::getFirstNonPHIIt(), I, II, insertRelocationStores(), insertRematerializationStores(), llvm::isa(), llvm::Last, llvm::Load, llvm::PromoteMemToReg(), llvm::SmallVectorTemplateBase< T, bool >::push_back(), llvm::SmallVectorImpl< T >::reserve(), llvm::ArrayRef< T >::size(), llvm::SmallVectorTemplateCommon< T, typename >::size(), llvm::sort(), llvm::Store, llvm::unique(), llvm::Instruction::users(), and Uses.

Referenced by insertParsePoints().

◆ rematerializeChain()

Instruction * rematerializeChain	(	ArrayRef< Instruction * >	ChainToBase,
		BasicBlock::iterator	InsertBefore,
		Value *	RootOfChain,
		Value *	AlternateLiveBase )

static

Definition at line 1352 of file RewriteStatepointsForGC.cpp.

References assert(), llvm::Instruction::insertBefore(), llvm::is_contained(), llvm::isa(), llvm::User::operand_values(), llvm::User::replaceUsesOfWith(), llvm::reverse(), and llvm::Value::setName().

Referenced by rematerializeLiveValues(), and rematerializeLiveValuesAtUses().

◆ rematerializeLiveValues()

void rematerializeLiveValues	(	const ScalarOptions &	Opts,
		CallBase *	Call,
		PartiallyConstructedSafepointRecord &	Info,
		PointerToBaseTy &	PointerToBase,
		RematCandTy &	RematerizationCandidates,
		TargetTransformInfo &	TTI )

static

Definition at line 2516 of file RewriteStatepointsForGC.cpp.

References assert(), Call, llvm::cast(), llvm::ilist_node_impl< OptionsT >::getIterator(), llvm::isa(), llvm::SmallVectorTemplateBase< T, bool >::push_back(), and rematerializeChain().

Referenced by insertParsePoints().

◆ rematerializeLiveValuesAtUses()

void rematerializeLiveValuesAtUses	(	const ScalarOptions &	Opts,
		RematCandTy &	RematerizationCandidates,
		MutableArrayRef< PartiallyConstructedSafepointRecord >	Records,
		PointerToBaseTy &	PointerToBase )

static

◆ setKnownBase()

void setKnownBase	(	Value *	V,
		bool	IsKnownBase,
		IsKnownBaseMapTy &	KnownBases )

static

Caches the IsKnownBase flag for a value and asserts that it wasn't present in the cache before.

Definition at line 656 of file RewriteStatepointsForGC.cpp.

References assert().

Referenced by findBaseDefiningValue(), findBaseDefiningValueOfVector(), and findBasePointer().

◆ shouldRewriteStatepointsIn()

bool shouldRewriteStatepointsIn ( Function & F )

static

Returns true if this function should be rewritten by this pass.

The main point of this function is as an extension point for custom logic.

Definition at line 2986 of file RewriteStatepointsForGC.cpp.

References assert(), F, and findGCStrategy().

Referenced by llvm::RewriteStatepointsForGC::run(), llvm::RewriteStatepointsForGC::runOnFunction(), and stripNonValidData().

◆ stripInvalidMetadataFromInstruction()

void stripInvalidMetadataFromInstruction ( Instruction & I )

static

Certain metadata on instructions are invalid after running RS4GC.

Optimizations that run after RS4GC can incorrectly use this metadata to optimize functions. We drop such metadata on the instruction.

Definition at line 2899 of file RewriteStatepointsForGC.cpp.

References I, and llvm::isa().

Referenced by stripNonValidDataFromBody().

◆ stripNonValidAttributesFromPrototype()

void stripNonValidAttributesFromPrototype ( Function & F )

static

Definition at line 2871 of file RewriteStatepointsForGC.cpp.

References A(), F, FnAttrsToStrip, llvm::Intrinsic::getAttributes(), getParamAndReturnAttributesToRemove(), and llvm::isa().

Referenced by stripNonValidData().

◆ stripNonValidData()

void stripNonValidData ( Module & M )

static

The IR fed into RewriteStatepointsForGC may have had attributes and metadata implying dereferenceability that are no longer valid/correct after RewriteStatepointsForGC has run.

This is because semantically, after RewriteStatepointsForGC runs, all calls to gc.statepoint "free" the entire heap. stripNonValidData (conservatively) restores correctness by erasing all attributes in the module that externally imply dereferenceability. Similar reasoning also applies to the noalias attributes and metadata. gc.statepoint can touch the entire heap including noalias objects. Apart from attributes and metadata, we also remove instructions that imply constant physical memory: llvm.invariant.start.

Definition at line 2997 of file RewriteStatepointsForGC.cpp.

References llvm::any_of(), assert(), F, shouldRewriteStatepointsIn(), stripNonValidAttributesFromPrototype(), and stripNonValidDataFromBody().

Referenced by llvm::RewriteStatepointsForGC::run().

◆ stripNonValidDataFromBody()

void stripNonValidDataFromBody ( Function & F )

static

Definition at line 2927 of file RewriteStatepointsForGC.cpp.

References Call, llvm::dyn_cast(), F, llvm::PoisonValue::get(), getParamAndReturnAttributesToRemove(), I, II, instructions, llvm::isa(), llvm::SmallVectorTemplateBase< T, bool >::push_back(), and stripInvalidMetadataFromInstruction().

Referenced by stripNonValidData().

◆ suffixed_name_or()

std::string suffixed_name_or	(	Value *	V,
		StringRef	Suffix,
		StringRef	DefaultName )

static

Definition at line 283 of file RewriteStatepointsForGC.cpp.

References llvm::StringRef::str().

Referenced by CreateGCRelocates(), findBasePointer(), and inlineGetBaseAndOffset().

Variable Documentation

◆ ClobberNonLive

bool ClobberNonLive = false

static

Definition at line 84 of file RewriteStatepointsForGC.cpp.

Referenced by relocationViaAlloca().

◆ ClobberNonLiveOverride

cl::opt< bool, true > ClobberNonLiveOverride("rs4gc-clobber-non-live", cl::location(ClobberNonLive), cl::Hidden)	(	"rs4gc-clobber-non-live"	,
		cl::location(ClobberNonLive)	,
		cl::Hidden	)

static

◆ FnAttrsToStrip

Attribute::AttrKind FnAttrsToStrip[]

staticconstexpr

Initial value:

=

{Attribute::Memory, Attribute::NoSync, Attribute::NoFree}

Definition at line 1432 of file RewriteStatepointsForGC.cpp.

Referenced by legalizeCallAttributes(), and stripNonValidAttributesFromPrototype().

Macros

Functions

Variables

Macro Definition Documentation

◆ DEBUG_TYPE

Function Documentation

◆ analyzeParsePointLiveness()

◆ areBothVectorOrScalar()

◆ AreEquivalentPhiNodes()

◆ chainToBasePointerCost()

◆ checkBasicSSA() [1/2]

◆ checkBasicSSA() [2/2]

◆ computeKillSet()

◆ computeLiveInValues() [1/2]

◆ computeLiveInValues() [2/2]

◆ computeLiveOutSeed()

◆ containsGCPtrType()

◆ CreateGCRelocates()

◆ findBaseDefiningValue()

◆ findBaseDefiningValueCached()

◆ findBaseDefiningValueOfVector()

◆ findBaseOrBDV()

◆ findBasePointer()

◆ findBasePointers() [1/2]

◆ findBasePointers() [2/2]

◆ findGCStrategy()

◆ findLiveReferences()

◆ findLiveSetAtInst()

◆ findRematerializableChainToBasePointer()

◆ findRematerializationCandidates()

◆ getDeoptBundleOperands()

◆ getDeoptLowering()

◆ getParamAndReturnAttributesToRemove()

◆ inlineGetBaseAndOffset()

◆ insertParsePoints()

◆ insertRelocationStores()

◆ insertRematerializationStores()

◆ insertUseHolderAfter()

◆ isGCPointerType()

◆ isHandledGCPointerType()

◆ isKnownBase()

◆ isOriginalBaseResult()

◆ isUnhandledGCPointerType()

◆ legalizeCallAttributes()

◆ makeStatepointExplicit()

◆ makeStatepointExplicitImpl()

◆ normalizeForInvokeSafepoint()

◆ operator<<()

◆ recomputeLiveInValues() [1/2]

◆ recomputeLiveInValues() [2/2]

◆ relocationViaAlloca()

◆ rematerializeChain()

◆ rematerializeLiveValues()

◆ rematerializeLiveValuesAtUses()

◆ setKnownBase()

◆ shouldRewriteStatepointsIn()

◆ stripInvalidMetadataFromInstruction()

◆ stripNonValidAttributesFromPrototype()

◆ stripNonValidData()

◆ stripNonValidDataFromBody()

◆ suffixed_name_or()

Variable Documentation

◆ ClobberNonLive

◆ ClobberNonLiveOverride

◆ FnAttrsToStrip