LICM.cpp File Reference

#include "llvm/Transforms/Scalar/LICM.h"
#include "llvm/ADT/PriorityWorklist.h"
#include "llvm/ADT/SetOperations.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Analysis/AliasSetTracker.h"
#include "llvm/Analysis/AssumptionCache.h"
#include "llvm/Analysis/CaptureTracking.h"
#include "llvm/Analysis/ConstantFolding.h"
#include "llvm/Analysis/GuardUtils.h"
#include "llvm/Analysis/LazyBlockFrequencyInfo.h"
#include "llvm/Analysis/Loads.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/Analysis/LoopIterator.h"
#include "llvm/Analysis/LoopNestAnalysis.h"
#include "llvm/Analysis/LoopPass.h"
#include "llvm/Analysis/MemorySSA.h"
#include "llvm/Analysis/MemorySSAUpdater.h"
#include "llvm/Analysis/MustExecute.h"
#include "llvm/Analysis/OptimizationRemarkEmitter.h"
#include "llvm/Analysis/ScalarEvolution.h"
#include "llvm/Analysis/TargetLibraryInfo.h"
#include "llvm/Analysis/TargetTransformInfo.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/CFG.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DebugInfoMetadata.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/InitializePasses.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/Utils/AssumeBundleBuilder.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:

Go to the source code of this file.

Namespaces
	llvm
	This is an optimization pass for GlobalISel generic memory operations.

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 (NumPromotionCandidates, "Number of promotion candidates")
	STATISTIC (NumLoadPromoted, "Number of load-only promotions")
	STATISTIC (NumLoadStorePromoted, "Number of load and store promotions")
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, bool LoopNestMode)
	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, ScalarEvolution *SE, 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)
	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 TargetLibraryInfo *TLI, const Loop *CurLoop, const LoopSafetyInfo *SafetyInfo, OptimizationRemarkEmitter *ORE, const Instruction *CtxI, AssumptionCache *AC, bool AllowSpeculation)
	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 (MemorySSA *MSSA, MemoryUse *MU, Loop *CurLoop, Instruction &I, SinkAndHoistLICMFlags &Flags)
static bool	pointerInvalidatedByBlock (BasicBlock &BB, MemorySSA &MSSA, MemoryUse &MU)
static Instruction *	cloneInstructionInExitBlock (Instruction &I, BasicBlock &ExitBlock, PHINode &PN, const LoopInfo *LI, const LoopSafetyInfo *SafetyInfo, MemorySSAUpdater &MSSAU)
static void	eraseInstruction (Instruction &I, ICFLoopSafetyInfo &SafetyInfo, MemorySSAUpdater &MSSAU)
static void	moveInstructionBefore (Instruction &I, Instruction &Dest, ICFLoopSafetyInfo &SafetyInfo, MemorySSAUpdater &MSSAU, ScalarEvolution *SE)
static void	foreachMemoryAccess (MemorySSA *MSSA, Loop *L, function_ref< void(Instruction *)> Fn)
static SmallVector< SmallSetVector< Value *, 8 >, 0 >	collectPromotionCandidates (MemorySSA *MSSA, AliasAnalysis *AA, Loop *L)
	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)"))
	licm
Loop Invariant Code	Motion
Loop Invariant Code	false

Macro Definition Documentation

DEBUG_TYPE

#define DEBUG_TYPE   "licm"

Definition at line 94 of file LICM.cpp.

Function Documentation

canSplitPredecessors()

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

static

Definition at line 1505 of file LICM.cpp.

References BB, llvm::LoopSafetyInfo::getBlockColors(), llvm::Instruction::getParent(), and llvm::predecessors().

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 1394 of file LICM.cpp.

References llvm::PHINode::addIncoming(), assert(), llvm::MemorySSAUpdater::createMemoryAccessInBB(), llvm::numbers::e, llvm::SmallVectorImpl< T >::emplace_back(), llvm::TinyPtrVector< EltTy >::front(), llvm::BasicBlock::front(), llvm::LoopSafetyInfo::getBlockColors(), llvm::BasicBlock::getFirstInsertionPt(), llvm::BasicBlock::getFirstNonPHI(), llvm::PHINode::getIncomingBlock(), llvm::BasicBlock::getInstList(), llvm::MemorySSA::getMemoryAccess(), llvm::MemorySSAUpdater::getMemorySSA(), llvm::PHINode::getNumIncomingValues(), llvm::Instruction::getParent(), llvm::OperandBundleUse::getTagID(), i, I, llvm::MemorySSAUpdater::insertDef(), llvm::MemorySSAUpdater::insertUse(), llvm::Instruction::isEHPad(), llvm::TinyPtrVector< EltTy >::size(), and llvm::LoopInfo::wouldBeOutOfLoopUseRequiringLCSSA().

Referenced by sinkThroughTriviallyReplaceablePHI().

collectPromotionCandidates()

static SmallVector< SmallSetVector< Value *, 8 >, 0 > collectPromotionCandidates ( MemorySSA *  MSSA, AliasAnalysis *  AA, Loop *  L  )

static

Definition at line 2242 of file LICM.cpp.

References llvm::AliasSetTracker::add(), llvm::SmallPtrSetImpl< PtrType >::contains(), llvm::erase_if(), foreachMemoryAccess(), I, llvm::SetVector< T, SmallVector< T, N >, SmallDenseSet< T, N > >::insert(), llvm::SmallPtrSetImpl< PtrType >::insert(), llvm::Loop::isLoopInvariant(), move, and SI.

eraseInstruction()

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

static

Definition at line 1466 of file LICM.cpp.

References I, llvm::ICFLoopSafetyInfo::removeInstruction(), and llvm::MemorySSAUpdater::removeMemoryAccess().

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

foreachMemoryAccess()

static void foreachMemoryAccess ( MemorySSA *  MSSA, Loop *  L, function_ref< void(Instruction *)>  Fn  )

static

Definition at line 2232 of file LICM.cpp.

References BB, llvm::LoopBase< BlockT, LoopT >::blocks(), and llvm::MemorySSA::getBlockAccesses().

Referenced by collectPromotionCandidates().

hoist()

static void hoist ( Instruction &  I, const DominatorTree *  DT, const Loop *  CurLoop, BasicBlock *  Dest, ICFLoopSafetyInfo *  SafetyInfo, MemorySSAUpdater &  MSSAU, ScalarEvolution *  SE, 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 1699 of file LICM.cpp.

References llvm::dbgs(), DEBUG_TYPE, llvm::OptimizationRemarkEmitter::emit(), llvm::BasicBlock::getFirstNonPHI(), llvm::Value::getNameOrAsOperand(), llvm::BasicBlock::getTerminator(), I, llvm::ICFLoopSafetyInfo::isGuaranteedToExecute(), LLVM_DEBUG, and moveInstructionBefore().

Referenced by llvm::hoistRegion().

INITIALIZE_PASS_BEGIN()

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

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 2351 of file LICM.cpp.

References assert(), BB, 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 1321 of file LICM.cpp.

References BB, llvm::LoopBase< BlockT, LoopT >::contains(), GEP, llvm::TargetTransformInfo::getInstructionCost(), llvm::Instruction::getParent(), and I.

Referenced by isNotUsedOrFreeInLoop().

isLoadInvariantInLoop()

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

static

Definition at line 1033 of file LICM.cpp.

References Addr, DL, get, llvm::CallBase::getArgOperand(), llvm::Value::getContext(), llvm::Module::getDataLayout(), llvm::TypeSize::getFixedSize(), llvm::LoopBase< BlockT, LoopT >::getHeader(), llvm::IntrinsicInst::getIntrinsicID(), llvm::Instruction::getModule(), llvm::User::getOperand(), llvm::Instruction::getParent(), llvm::LoadInst::getPointerAddressSpace(), llvm::ConstantInt::getSExtValue(), llvm::Value::getType(), llvm::ConstantInt::isNegative(), llvm::LinearPolySize< LeafTy >::isScalable(), MaxNumUsesTraversed, llvm::DominatorTreeBase< NodeT, IsPostDom >::properlyDominates(), and llvm::Value::use_empty().

Referenced by llvm::canSinkOrHoistInst().

isNotUsedOrFreeInLoop()

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

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 1352 of file LICM.cpp.

References BB, llvm::LoopBase< BlockT, LoopT >::contains(), llvm::LoopSafetyInfo::getBlockColors(), llvm::User::getNumOperands(), llvm::Instruction::getParent(), llvm::Value::hasOneUser(), I, isFreeInLoop(), and llvm::Instruction::user_back().

Referenced by llvm::sinkRegion().

isSafeToExecuteUnconditionally()

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

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 1744 of file LICM.cpp.

References DEBUG_TYPE, llvm::OptimizationRemarkEmitter::emit(), llvm::LoopSafetyInfo::isGuaranteedToExecute(), llvm::Loop::isLoopInvariant(), and llvm::isSafeToSpeculativelyExecute().

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 1312 of file LICM.cpp.

References I, and llvm::PHINode::incoming_values().

Referenced by sink(), and sinkThroughTriviallyReplaceablePHI().

moveInstructionBefore()

static void moveInstructionBefore ( Instruction &  I, Instruction &  Dest, ICFLoopSafetyInfo &  SafetyInfo, MemorySSAUpdater &  MSSAU, ScalarEvolution *  SE  )

static

Definition at line 1473 of file LICM.cpp.

References llvm::ScalarEvolution::forgetValue(), llvm::MemorySSA::getMemoryAccess(), llvm::MemorySSAUpdater::getMemorySSA(), llvm::Instruction::getParent(), I, llvm::ICFLoopSafetyInfo::insertInstructionTo(), llvm::MemorySSAUpdater::moveToPlace(), and llvm::ICFLoopSafetyInfo::removeInstruction().

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

pointerInvalidatedByBlock()

bool pointerInvalidatedByBlock ( BasicBlock &  BB, MemorySSA &  MSSA, MemoryUse &  MU  )

static

Definition at line 2339 of file LICM.cpp.

References BB, llvm::MemoryAccess::getBlock(), llvm::MemorySSA::getBlockDefs(), and llvm::MemorySSA::locallyDominates().

Referenced by pointerInvalidatedByLoop().

pointerInvalidatedByLoop()

static bool pointerInvalidatedByLoop ( MemorySSA *  MSSA, MemoryUse *  MU, Loop *  CurLoop, Instruction &  I, SinkAndHoistLICMFlags &  Flags  )

static

Definition at line 2293 of file LICM.cpp.

References BB, llvm::LoopBase< BlockT, LoopT >::contains(), llvm::LoopBase< BlockT, LoopT >::getBlocks(), llvm::MemorySSAWalker::getClobberingMemoryAccess(), llvm::MemoryUseOrDef::getDefiningAccess(), llvm::SinkAndHoistLICMFlags::getIsSink(), llvm::MemorySSA::getSkipSelfWalker(), I, llvm::SinkAndHoistLICMFlags::incrementClobberingCalls(), llvm::MemorySSA::isLiveOnEntryDef(), pointerInvalidatedByBlock(), llvm::Sched::Source, llvm::SinkAndHoistLICMFlags::tooManyClobberingCalls(), and llvm::SinkAndHoistLICMFlags::tooManyMemoryAccesses().

Referenced by llvm::canSinkOrHoistInst().

sink()

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

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 1594 of file LICM.cpp.

References assert(), BB, canSplitPredecessors(), llvm::LoopBase< BlockT, LoopT >::contains(), llvm::SmallPtrSetImpl< PtrType >::count(), llvm::dbgs(), DEBUG_TYPE, llvm::OptimizationRemarkEmitter::emit(), llvm::SmallPtrSetImplBase::empty(), eraseInstruction(), get, llvm::PHINode::getIncomingBlock(), llvm::Instruction::getParent(), llvm::LoopBase< BlockT, LoopT >::getUniqueExitBlocks(), I, llvm::SmallPtrSetImpl< PtrType >::insert(), llvm::DominatorTree::isReachableFromEntry(), isTriviallyReplaceablePHI(), LLVM_DEBUG, llvm::Value::replaceAllUsesWith(), sinkThroughTriviallyReplaceablePHI(), splitPredecessorsOfLoopExit(), 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 1487 of file LICM.cpp.

References assert(), cloneInstructionInExitBlock(), llvm::DenseMapBase< SmallDenseMap< KeyT, ValueT, 4, DenseMapInfo< KeyT >, llvm::detail::DenseMapPair< KeyT, ValueT > >, KeyT, ValueT, DenseMapInfo< KeyT >, llvm::detail::DenseMapPair< KeyT, ValueT > >::end(), llvm::DenseMapBase< SmallDenseMap< KeyT, ValueT, 4, DenseMapInfo< KeyT >, llvm::detail::DenseMapPair< KeyT, ValueT > >, KeyT, ValueT, DenseMapInfo< KeyT >, llvm::detail::DenseMapPair< KeyT, ValueT > >::find(), llvm::Instruction::getParent(), I, 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 1522 of file LICM.cpp.

References assert(), llvm::SetVector< T, SmallVector< T, N >, SmallDenseSet< T, N > >::begin(), llvm::LoopBase< BlockT, LoopT >::contains(), llvm::LoopSafetyInfo::copyColors(), llvm::SmallPtrSetImpl< PtrType >::count(), llvm::SetVector< T, SmallVector< T, N >, SmallDenseSet< T, N > >::empty(), 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() [1/9]

STATISTIC	(	NumClonedBranches	,
		"Number of branches cloned"
	)

STATISTIC() [2/9]

STATISTIC	(	NumCreatedBlocks	,
		"Number of blocks created"
	)

STATISTIC() [3/9]

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

STATISTIC() [4/9]

STATISTIC	(	NumLoadPromoted	,
		"Number of load-only promotions"
	)

STATISTIC() [5/9]

STATISTIC	(	NumLoadStorePromoted	,
		"Number of load and store promotions"
	)

STATISTIC() [6/9]

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

STATISTIC() [7/9]

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

STATISTIC() [8/9]

STATISTIC	(	NumPromotionCandidates	,
		"Number of promotion candidates"
	)

STATISTIC() [9/9]

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

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().

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.

false

Loop Invariant Code false

Definition at line 342 of file LICM.cpp.

licm

licm

Definition at line 342 of file LICM.cpp.

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 342 of file LICM.cpp.