#include "llvm/Transforms/Scalar/LICM.h"
#include "llvm/ADT/SetOperations.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Analysis/AliasSetTracker.h"
#include "llvm/Analysis/BasicAliasAnalysis.h"
#include "llvm/Analysis/CaptureTracking.h"
#include "llvm/Analysis/ConstantFolding.h"
#include "llvm/Analysis/GlobalsModRef.h"
#include "llvm/Analysis/GuardUtils.h"
#include "llvm/Analysis/Loads.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/Analysis/LoopIterator.h"
#include "llvm/Analysis/LoopPass.h"
#include "llvm/Analysis/MemoryBuiltins.h"
#include "llvm/Analysis/MemorySSA.h"
#include "llvm/Analysis/MemorySSAUpdater.h"
#include "llvm/Analysis/OptimizationRemarkEmitter.h"
#include "llvm/Analysis/ScalarEvolution.h"
#include "llvm/Analysis/ScalarEvolutionAliasAnalysis.h"
#include "llvm/Analysis/TargetLibraryInfo.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/CFG.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/Metadata.h"
#include "llvm/IR/PatternMatch.h"
#include "llvm/IR/PredIteratorCache.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Transforms/Scalar.h"
#include "llvm/Transforms/Scalar/LoopPassManager.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/Transforms/Utils/LoopUtils.h"
#include "llvm/Transforms/Utils/SSAUpdater.h"
#include <algorithm>
#include <utility>

Include dependency graph for LICM.cpp:

Macros
#define	DEBUG_TYPE "licm"

Functions
	STATISTIC (NumCreatedBlocks, "Number of blocks created")

	STATISTIC (NumClonedBranches, "Number of branches cloned")

	STATISTIC (NumSunk, "Number of instructions sunk out of loop")

	STATISTIC (NumHoisted, "Number of instructions hoisted out of loop")

	STATISTIC (NumMovedLoads, "Number of load insts hoisted or sunk")

	STATISTIC (NumMovedCalls, "Number of call insts hoisted or sunk")

	STATISTIC (NumPromoted, "Number of memory locations promoted to registers")

static bool	inSubLoop (BasicBlock BB, Loop CurLoop, LoopInfo *LI)
	Little predicate that returns true if the specified basic block is in a subloop of the current one, not the current one itself. More...

static bool	isNotUsedOrFreeInLoop (const Instruction &I, const Loop CurLoop, const LoopSafetyInfo SafetyInfo, TargetTransformInfo *TTI, bool &FreeInLoop)
	Return true if the only users of this instruction are outside of the loop. More...

static void	hoist (Instruction &I, const DominatorTree DT, const Loop CurLoop, BasicBlock Dest, ICFLoopSafetyInfo SafetyInfo, MemorySSAUpdater MSSAU, OptimizationRemarkEmitter ORE)
	When an instruction is found to only use loop invariant operands that is safe to hoist, this instruction is called to do the dirty work. More...

static bool	sink (Instruction &I, LoopInfo LI, DominatorTree DT, const Loop CurLoop, ICFLoopSafetyInfo SafetyInfo, MemorySSAUpdater MSSAU, OptimizationRemarkEmitter ORE, bool FreeInLoop)
	When an instruction is found to only be used outside of the loop, this function moves it to the exit blocks and patches up SSA form as needed. More...

static bool	isSafeToExecuteUnconditionally (Instruction &Inst, const DominatorTree DT, const Loop CurLoop, const LoopSafetyInfo SafetyInfo, OptimizationRemarkEmitter ORE, const Instruction *CtxI)
	Only sink or hoist an instruction if it is not a trapping instruction, or if the instruction is known not to trap when moved to the preheader. More...

static bool	pointerInvalidatedByLoop (MemoryLocation MemLoc, AliasSetTracker CurAST, Loop CurLoop, AliasAnalysis *AA)

static bool	pointerInvalidatedByLoopWithMSSA (MemorySSA MSSA, MemoryUse MU, Loop *CurLoop)

static Instruction *	CloneInstructionInExitBlock (Instruction &I, BasicBlock &ExitBlock, PHINode &PN, const LoopInfo LI, const LoopSafetyInfo SafetyInfo, MemorySSAUpdater *MSSAU)

static void	eraseInstruction (Instruction &I, ICFLoopSafetyInfo &SafetyInfo, AliasSetTracker AST, MemorySSAUpdater MSSAU)

static void	moveInstructionBefore (Instruction &I, Instruction &Dest, ICFLoopSafetyInfo &SafetyInfo)

	INITIALIZE_PASS_BEGIN (LegacyLICMPass, "licm", "Loop Invariant Code Motion", false, false) INITIALIZE_PASS_END(LegacyLICMPass

static bool	isLoadInvariantInLoop (LoadInst LI, DominatorTree DT, Loop *CurLoop)

static bool	isTriviallyReplaceablePHI (const PHINode &PN, const Instruction &I)
	Returns true if a PHINode is a trivially replaceable with an Instruction. More...

static bool	isFreeInLoop (const Instruction &I, const Loop CurLoop, const TargetTransformInfo TTI)
	Return true if the instruction is free in the loop. More...

static Instruction *	sinkThroughTriviallyReplaceablePHI (PHINode TPN, Instruction I, LoopInfo LI, SmallDenseMap< BasicBlock , Instruction , 32 > &SunkCopies, const LoopSafetyInfo SafetyInfo, const Loop CurLoop, MemorySSAUpdater MSSAU)

static bool	canSplitPredecessors (PHINode PN, LoopSafetyInfo SafetyInfo)

static void	splitPredecessorsOfLoopExit (PHINode PN, DominatorTree DT, LoopInfo LI, const Loop CurLoop, LoopSafetyInfo SafetyInfo, MemorySSAUpdater MSSAU)

Variables
static cl::opt< bool >	DisablePromotion ("disable-licm-promotion", cl::Hidden, cl::init(false), cl::desc("Disable memory promotion in LICM pass"))
	Memory promotion is enabled by default. More...

static cl::opt< bool >	ControlFlowHoisting ("licm-control-flow-hoisting", cl::Hidden, cl::init(false), cl::desc("Enable control flow (and PHI) hoisting in LICM"))

static cl::opt< uint32_t >	MaxNumUsesTraversed ("licm-max-num-uses-traversed", cl::Hidden, cl::init(8), cl::desc("Max num uses visited for identifying load " "invariance in loop using invariant start (default = 8)"))

static cl::opt< int >	LICMN2Theshold ("licm-n2-threshold", cl::Hidden, cl::init(0), cl::desc("How many instruction to cross product using AA"))

static cl::opt< bool >	EnableLicmCap ("enable-licm-cap", cl::init(false), cl::Hidden, cl::desc("Enable imprecision in LICM (uses MemorySSA cap) in " "pathological cases, in exchange for faster compile"))

	licm

Loop Invariant Code	Motion

Loop Invariant Code	false

Macro Definition Documentation

◆ DEBUG_TYPE

#define DEBUG_TYPE "licm"

Definition at line 79 of file LICM.cpp.

Referenced by llvm::canSinkOrHoistInst(), hoist(), isSafeToExecuteUnconditionally(), llvm::promoteLoopAccessesToScalars(), and sink().

Function Documentation

◆ canSplitPredecessors()

static bool canSplitPredecessors	(	PHINode *	PN,
		LoopSafetyInfo *	SafetyInfo
	)

static

Definition at line 1337 of file LICM.cpp.

References llvm::BasicBlock::canSplitPredecessors(), E, llvm::LoopSafetyInfo::getBlockColors(), llvm::BasicBlock::getFirstNonPHI(), llvm::Instruction::getParent(), llvm::BasicBlock::getTerminator(), llvm::Instruction::isEHPad(), llvm::pred_begin(), and llvm::pred_end().

Referenced by sink().

◆ CloneInstructionInExitBlock()

static Instruction * CloneInstructionInExitBlock	(	Instruction &	I,
		BasicBlock &	ExitBlock,
		PHINode &	PN,
		const LoopInfo *	LI,
		const LoopSafetyInfo *	SafetyInfo,
		MemorySSAUpdater *	MSSAU
	)

static

Definition at line 1227 of file LICM.cpp.

References llvm::PHINode::addIncoming(), assert(), llvm::MemorySSA::Beginning, llvm::Instruction::clone(), llvm::CallInst::Create(), llvm::PHINode::Create(), llvm::MemorySSAUpdater::createMemoryAccessInBB(), llvm::SmallVectorImpl< T >::emplace_back(), llvm::StringRef::empty(), llvm::TinyPtrVector< EltTy >::front(), llvm::BasicBlock::front(), llvm::LoopSafetyInfo::getBlockColors(), llvm::BasicBlock::getFirstInsertionPt(), llvm::PHINode::getIncomingBlock(), llvm::BasicBlock::getInstList(), llvm::LoopInfoBase< BlockT, LoopT >::getLoopFor(), llvm::MemorySSA::getMemoryAccess(), llvm::MemorySSAUpdater::getMemorySSA(), llvm::Value::getName(), llvm::PHINode::getNumIncomingValues(), llvm::Instruction::getParent(), llvm::OperandBundleUse::getTagID(), llvm::iplist_impl< IntrusiveListT, TraitsT >::insert(), llvm::MemorySSAUpdater::insertDef(), llvm::MemorySSAUpdater::insertUse(), llvm::Instruction::isEHPad(), llvm::LLVMContext::OB_funclet, llvm::User::op_begin(), llvm::User::op_end(), llvm::Value::setName(), and llvm::TinyPtrVector< EltTy >::size().

Referenced by sinkThroughTriviallyReplaceablePHI().

◆ eraseInstruction()

static void eraseInstruction	(	Instruction &	I,
		ICFLoopSafetyInfo &	SafetyInfo,
		AliasSetTracker *	AST,
		MemorySSAUpdater *	MSSAU
	)

static

Definition at line 1302 of file LICM.cpp.

References llvm::AliasSetTracker::deleteValue(), llvm::Instruction::eraseFromParent(), llvm::ICFLoopSafetyInfo::removeInstruction(), and llvm::MemorySSAUpdater::removeMemoryAccess().

Referenced by llvm::slpvectorizer::BoUpSLP::getORE(), llvm::hoistRegion(), operator<<(), llvm::slpvectorizer::BoUpSLP::optimizeGatherSequence(), llvm::promoteLoopAccessesToScalars(), sink(), llvm::sinkRegion(), and llvm::slpvectorizer::BoUpSLP::vectorizeTree().

◆ hoist()

static void hoist	(	Instruction &	I,
		const DominatorTree *	DT,
		const Loop *	CurLoop,
		BasicBlock *	Dest,
		ICFLoopSafetyInfo *	SafetyInfo,
		MemorySSAUpdater *	MSSAU,
		OptimizationRemarkEmitter *	ORE
	)

static

When an instruction is found to only use loop invariant operands that is safe to hoist, this instruction is called to do the dirty work.

Definition at line 1529 of file LICM.cpp.

References llvm::dbgs(), DEBUG_TYPE, llvm::Instruction::dropUnknownNonDebugMetadata(), llvm::OptimizationRemarkEmitter::emit(), llvm::MemorySSA::End, llvm::BasicBlock::getFirstNonPHI(), llvm::MemorySSA::getMemoryAccess(), llvm::MemorySSAUpdater::getMemorySSA(), llvm::Value::getName(), llvm::BasicBlock::getTerminator(), llvm::Instruction::hasMetadataOtherThanDebugLoc(), llvm::ICFLoopSafetyInfo::isGuaranteedToExecute(), LLVM_DEBUG, moveInstructionBefore(), llvm::MemorySSAUpdater::moveToPlace(), and llvm::Instruction::setDebugLoc().

Referenced by llvm::hoistRegion().

◆ INITIALIZE_PASS_BEGIN()

INITIALIZE_PASS_BEGIN	(	LegacyLICMPass	,
		"licm"	,
		"Loop Invariant Code Motion"	,
		false	,
		false
	)

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

◆ inSubLoop()

static bool inSubLoop	(	BasicBlock *	BB,
		Loop *	CurLoop,
		LoopInfo *	LI
	)

static

Little predicate that returns true if the specified basic block is in a subloop of the current one, not the current one itself.

Definition at line 2112 of file LICM.cpp.

References assert(), llvm::LoopBase< BlockT, LoopT >::contains(), and llvm::LoopInfoBase< BlockT, LoopT >::getLoopFor().

Referenced by llvm::hoistRegion(), and llvm::sinkRegion().

◆ isFreeInLoop()

static bool isFreeInLoop	(	const Instruction &	I,
		const Loop *	CurLoop,
		const TargetTransformInfo *	TTI
	)

static

Return true if the instruction is free in the loop.

Definition at line 1167 of file LICM.cpp.

References llvm::LoopBase< BlockT, LoopT >::contains(), GEP, llvm::Instruction::getParent(), llvm::TargetTransformInfo::getUserCost(), and llvm::TargetTransformInfo::TCC_Free.

Referenced by isNotUsedOrFreeInLoop().

◆ isLoadInvariantInLoop()

static bool isLoadInvariantInLoop	(	LoadInst *	LI,
		DominatorTree *	DT,
		Loop *	CurLoop
	)

static

Definition at line 896 of file LICM.cpp.

References llvm::dyn_cast(), llvm::PointerType::get(), llvm::CallBase::getArgOperand(), llvm::MemorySSA::getBlockAccesses(), llvm::MemorySSA::getBlockDefs(), llvm::LoopBase< BlockT, LoopT >::getBlocks(), llvm::Value::getContext(), llvm::Module::getDataLayout(), llvm::LoopBase< BlockT, LoopT >::getHeader(), llvm::Type::getInt8Ty(), llvm::IntrinsicInst::getIntrinsicID(), llvm::MemorySSAUpdater::getMemorySSA(), llvm::Instruction::getModule(), llvm::User::getOperand(), llvm::Instruction::getParent(), llvm::LoadInst::getPointerAddressSpace(), llvm::Value::getType(), llvm::DataLayout::getTypeSizeInBits(), I, llvm::Intrinsic::invariant_start, MaxNumUsesTraversed, llvm::DominatorTreeBase< NodeT, IsPostDom >::properlyDominates(), llvm::Value::use_empty(), and llvm::Value::users().

Referenced by llvm::canSinkOrHoistInst().

◆ isNotUsedOrFreeInLoop()

static bool isNotUsedOrFreeInLoop	(	const Instruction &	I,
		const Loop *	CurLoop,
		const LoopSafetyInfo *	SafetyInfo,
		TargetTransformInfo *	TTI,
		bool &	FreeInLoop
	)

static

Return true if the only users of this instruction are outside of the loop.

If this is true, we can sink the instruction to the exit blocks of the loop.

We also return true if the instruction could be folded away in lowering. (e.g., a GEP can be folded into a load as an addressing mode in the loop).

Definition at line 1195 of file LICM.cpp.

References llvm::LoopBase< BlockT, LoopT >::contains(), llvm::LoopSafetyInfo::getBlockColors(), llvm::BasicBlock::getParent(), llvm::BasicBlock::getTerminator(), isFreeInLoop(), and llvm::Value::users().

Referenced by llvm::sinkRegion().

◆ isSafeToExecuteUnconditionally()

static bool isSafeToExecuteUnconditionally	(	Instruction &	Inst,
		const DominatorTree *	DT,
		const Loop *	CurLoop,
		const LoopSafetyInfo *	SafetyInfo,
		OptimizationRemarkEmitter *	ORE,
		const Instruction *	CtxI
	)

static

Only sink or hoist an instruction if it is not a trapping instruction, or if the instruction is known not to trap when moved to the preheader.

or if it is a trapping instruction and is guaranteed to execute.

Definition at line 1582 of file LICM.cpp.

References llvm::PHINode::addIncoming(), llvm::LoopBase< BlockT, LoopT >::contains(), llvm::AliasSetTracker::copyValue(), llvm::SetVector< T, SmallVector< T, N >, SmallDenseSet< T, N > >::count(), llvm::PHINode::Create(), DEBUG_TYPE, llvm::AliasSetTracker::deleteValue(), llvm::dyn_cast(), llvm::OptimizationRemarkEmitter::emit(), llvm::BasicBlock::front(), llvm::PredIteratorCache::get(), llvm::LoopInfoBase< BlockT, LoopT >::getLoopFor(), llvm::getPointerOperand(), I, llvm::isAllocLikeFn(), llvm::LoopSafetyInfo::isGuaranteedToExecute(), llvm::Loop::isLoopInvariant(), llvm::isSafeToSpeculativelyExecute(), llvm::PointerMayBeCaptured(), llvm::ICFLoopSafetyInfo::removeInstruction(), llvm::Instruction::setAAMetadata(), llvm::StoreInst::setAlignment(), llvm::Instruction::setDebugLoc(), llvm::StoreInst::setOrdering(), llvm::SmallVectorBase::size(), llvm::PredIteratorCache::size(), SSA, and llvm::Unordered.

Referenced by llvm::hoistRegion(), and llvm::promoteLoopAccessesToScalars().

◆ isTriviallyReplaceablePHI()

static bool isTriviallyReplaceablePHI	(	const PHINode &	PN,
		const Instruction &	I
	)

static

Returns true if a PHINode is a trivially replaceable with an Instruction.

This is true when all incoming values are that instruction. This pattern occurs most often with LCSSA PHI nodes.

Definition at line 1158 of file LICM.cpp.

References llvm::PHINode::incoming_values().

Referenced by sink(), and sinkThroughTriviallyReplaceablePHI().

◆ moveInstructionBefore()

static void moveInstructionBefore	(	Instruction &	I,
		Instruction &	Dest,
		ICFLoopSafetyInfo &	SafetyInfo
	)

static

Definition at line 1312 of file LICM.cpp.

References llvm::Instruction::getParent(), llvm::ICFLoopSafetyInfo::insertInstructionTo(), llvm::Instruction::moveBefore(), and llvm::ICFLoopSafetyInfo::removeInstruction().

Referenced by hoist(), and llvm::hoistRegion().

◆ pointerInvalidatedByLoop()

static bool pointerInvalidatedByLoop	(	MemoryLocation	MemLoc,
		AliasSetTracker *	CurAST,
		Loop *	CurLoop,
		AliasAnalysis *	AA
	)

static

Definition at line 2050 of file LICM.cpp.

References llvm::LoopBase< BlockT, LoopT >::begin(), llvm::dbgs(), llvm::LoopBase< BlockT, LoopT >::end(), llvm::AliasSetTracker::getAliasSetFor(), llvm::LoopBase< BlockT, LoopT >::getBlocks(), llvm::AAResults::getModRefInfo(), I, llvm::AliasSet::isMod(), llvm::isModSet(), LICMN2Theshold, LLVM_DEBUG, N, and llvm::MemoryLocation::Ptr.

Referenced by llvm::canSinkOrHoistInst().

◆ pointerInvalidatedByLoopWithMSSA()

static bool pointerInvalidatedByLoopWithMSSA	(	MemorySSA *	MSSA,
		MemoryUse *	MU,
		Loop *	CurLoop
	)

static

Definition at line 2097 of file LICM.cpp.

References llvm::LoopBase< BlockT, LoopT >::contains(), EnableLicmCap, llvm::MemoryAccess::getBlock(), llvm::MemorySSAWalker::getClobberingMemoryAccess(), llvm::MemoryUseOrDef::getDefiningAccess(), llvm::MemorySSA::getSkipSelfWalker(), llvm::MemorySSA::isLiveOnEntryDef(), and llvm::Sched::Source.

Referenced by llvm::canSinkOrHoistInst().

◆ sink()

static bool sink	(	Instruction &	I,
		LoopInfo *	LI,
		DominatorTree *	DT,
		const Loop *	CurLoop,
		ICFLoopSafetyInfo *	SafetyInfo,
		MemorySSAUpdater *	MSSAU,
		OptimizationRemarkEmitter *	ORE,
		bool	FreeInLoop
	)

static

When an instruction is found to only be used outside of the loop, this function moves it to the exit blocks and patches up SSA form as needed.

This method is guaranteed to remove the original instruction from its position, and may either delete it or move it to outside of the loop.

Definition at line 1427 of file LICM.cpp.

References assert(), llvm::SmallVectorTemplateCommon< T >::begin(), canSplitPredecessors(), llvm::LoopBase< BlockT, LoopT >::contains(), llvm::SmallPtrSetImpl< PtrType >::count(), llvm::dbgs(), DEBUG_TYPE, llvm::OptimizationRemarkEmitter::emit(), llvm::SmallPtrSetImplBase::empty(), llvm::SmallVectorTemplateCommon< T >::end(), eraseInstruction(), llvm::UndefValue::get(), llvm::PHINode::getIncomingBlock(), llvm::Instruction::getParent(), llvm::Value::getType(), llvm::LoopBase< BlockT, LoopT >::getUniqueExitBlocks(), llvm::SmallPtrSetImpl< PtrType >::insert(), llvm::DominatorTree::isReachableFromEntry(), isTriviallyReplaceablePHI(), LLVM_DEBUG, llvm::Value::replaceAllUsesWith(), sinkThroughTriviallyReplaceablePHI(), splitPredecessorsOfLoopExit(), llvm::Value::user_begin(), llvm::Value::user_end(), and Users.

Referenced by llvm::sinkRegion().

◆ sinkThroughTriviallyReplaceablePHI()

static Instruction* sinkThroughTriviallyReplaceablePHI	(	PHINode *	TPN,
		Instruction *	I,
		LoopInfo *	LI,
		SmallDenseMap< BasicBlock , Instruction , 32 > &	SunkCopies,
		const LoopSafetyInfo *	SafetyInfo,
		const Loop *	CurLoop,
		MemorySSAUpdater *	MSSAU
	)

static

Definition at line 1319 of file LICM.cpp.

References assert(), CloneInstructionInExitBlock(), llvm::DenseMapBase< SmallDenseMap< KeyT, ValueT, InlineBuckets, KeyInfoT, BucketT >, KeyT, ValueT, KeyInfoT, BucketT >::end(), llvm::DenseMapBase< SmallDenseMap< KeyT, ValueT, InlineBuckets, KeyInfoT, BucketT >, KeyT, ValueT, KeyInfoT, BucketT >::find(), llvm::Instruction::getParent(), and isTriviallyReplaceablePHI().

Referenced by sink().

◆ splitPredecessorsOfLoopExit()

static void splitPredecessorsOfLoopExit	(	PHINode *	PN,
		DominatorTree *	DT,
		LoopInfo *	LI,
		const Loop *	CurLoop,
		LoopSafetyInfo *	SafetyInfo,
		MemorySSAUpdater *	MSSAU
	)

static

Definition at line 1355 of file LICM.cpp.

References assert(), llvm::SetVector< T, SmallVector< T, N >, SmallDenseSet< T, N > >::begin(), llvm::SmallVectorTemplateCommon< T >::begin(), llvm::LoopBase< BlockT, LoopT >::contains(), llvm::LoopSafetyInfo::copyColors(), llvm::SetVector< T, SmallVector< T, N >, SmallDenseSet< T, N > >::empty(), llvm::SmallVectorTemplateCommon< T >::end(), llvm::PHINode::getBasicBlockIndex(), llvm::LoopSafetyInfo::getBlockColors(), llvm::Instruction::getParent(), llvm::LoopBase< BlockT, LoopT >::getUniqueExitBlocks(), llvm::pred_begin(), llvm::pred_end(), llvm::SetVector< T, SmallVector< T, N >, SmallDenseSet< T, N > >::remove(), and llvm::SplitBlockPredecessors().

Referenced by sink().

◆ STATISTIC() [1/7]

STATISTIC	(	NumCreatedBlocks	,
		"Number of blocks created"
	)

◆ STATISTIC() [2/7]

STATISTIC	(	NumClonedBranches	,
		"Number of branches cloned"
	)

◆ STATISTIC() [3/7]

STATISTIC	(	NumSunk	,
		"Number of instructions sunk out of loop"
	)

◆ STATISTIC() [4/7]

STATISTIC	(	NumHoisted	,
		"Number of instructions hoisted out of loop"
	)

◆ STATISTIC() [5/7]

STATISTIC	(	NumMovedLoads	,
		"Number of load insts hoisted or sunk"
	)

◆ STATISTIC() [6/7]

STATISTIC	(	NumMovedCalls	,
		"Number of call insts hoisted or sunk"
	)

◆ STATISTIC() [7/7]

STATISTIC	(	NumPromoted	,
		"Number of memory locations promoted to registers"
	)

Variable Documentation

◆ ControlFlowHoisting

cl::opt<bool> ControlFlowHoisting("licm-control-flow-hoisting", cl::Hidden, cl::init(false), cl::desc("Enable control flow (and PHI) hoisting in LICM"))

static

Referenced by llvm::hoistRegion(), and llvm::sinkRegion().

◆ DisablePromotion

cl::opt<bool> DisablePromotion("disable-licm-promotion", cl::Hidden, cl::init(false), cl::desc("Disable memory promotion in LICM pass"))

static

Memory promotion is enabled by default.

Referenced by llvm::createLICMPass().

◆ EnableLicmCap

cl::opt<bool> EnableLicmCap("enable-licm-cap", cl::init(false), cl::Hidden, cl::desc("Enable imprecision in LICM (uses MemorySSA cap) in " "pathological cases, in exchange for faster compile"))

static

Referenced by llvm::canSinkOrHoistInst(), and pointerInvalidatedByLoopWithMSSA().

◆ false

Loop Invariant Code false

Definition at line 275 of file LICM.cpp.

◆ licm

licm

Definition at line 275 of file LICM.cpp.

◆ LICMN2Theshold

cl::opt<int> LICMN2Theshold("licm-n2-threshold", cl::Hidden, cl::init(0), cl::desc("How many instruction to cross product using AA"))

static

Referenced by pointerInvalidatedByLoop().

◆ MaxNumUsesTraversed

cl::opt<uint32_t> MaxNumUsesTraversed("licm-max-num-uses-traversed", cl::Hidden, cl::init(8), cl::desc("Max num uses visited for identifying load " "invariance in loop using invariant start (default = 8)"))

static

Referenced by isLoadInvariantInLoop().

◆ Motion

Loop Invariant Code Motion

Definition at line 275 of file LICM.cpp.

Macros

Functions

Variables

Macro Definition Documentation

◆ DEBUG_TYPE

Function Documentation

◆ canSplitPredecessors()

◆ CloneInstructionInExitBlock()

◆ eraseInstruction()

◆ hoist()

◆ INITIALIZE_PASS_BEGIN()

◆ inSubLoop()

◆ isFreeInLoop()

◆ isLoadInvariantInLoop()

◆ isNotUsedOrFreeInLoop()

◆ isSafeToExecuteUnconditionally()

◆ isTriviallyReplaceablePHI()

◆ moveInstructionBefore()

◆ pointerInvalidatedByLoop()

◆ pointerInvalidatedByLoopWithMSSA()

◆ sink()

◆ sinkThroughTriviallyReplaceablePHI()

◆ splitPredecessorsOfLoopExit()

◆ STATISTIC() [1/7]

◆ STATISTIC() [2/7]

◆ STATISTIC() [3/7]

◆ STATISTIC() [4/7]

◆ STATISTIC() [5/7]

◆ STATISTIC() [6/7]

◆ STATISTIC() [7/7]

Variable Documentation

◆ ControlFlowHoisting

◆ DisablePromotion

◆ EnableLicmCap

◆ false

◆ licm

◆ LICMN2Theshold

◆ MaxNumUsesTraversed

◆ Motion