LoopVectorizationLegality checks if it is legal to vectorize a loop, and to what vectorization factor. More...

#include "llvm/Transforms/Vectorize/LoopVectorizationLegality.h"

Public Types
using	ReductionList = MapVector< PHINode *, RecurrenceDescriptor >
	ReductionList contains the reduction descriptors for all of the reductions that were found in the loop.

using	InductionList = MapVector< PHINode *, InductionDescriptor >
	InductionList saves induction variables and maps them to the induction descriptor.

using	RecurrenceSet = SmallPtrSet< const PHINode *, 8 >
	RecurrenceSet contains the phi nodes that are recurrences other than inductions and reductions.

Public Member Functions
	LoopVectorizationLegality (Loop L, PredicatedScalarEvolution &PSE, DominatorTree DT, TargetTransformInfo TTI, TargetLibraryInfo TLI, Function F, LoopAccessInfoManager &LAIs, LoopInfo LI, OptimizationRemarkEmitter ORE, LoopVectorizationRequirements R, LoopVectorizeHints H, DemandedBits DB, AssumptionCache AC, BlockFrequencyInfo BFI, ProfileSummaryInfo *PSI)

bool	canVectorize (bool UseVPlanNativePath)
	Returns true if it is legal to vectorize this loop.

bool	canVectorizeFPMath (bool EnableStrictReductions)
	Returns true if it is legal to vectorize the FP math operations in this loop.

bool	canFoldTailByMasking () const
	Return true if we can vectorize this loop while folding its tail by masking.

void	prepareToFoldTailByMasking ()
	Mark all respective loads/stores for masking.

PHINode *	getPrimaryInduction ()
	Returns the primary induction variable.

const ReductionList &	getReductionVars () const
	Returns the reduction variables found in the loop.

const InductionList &	getInductionVars () const
	Returns the induction variables found in the loop.

RecurrenceSet &	getFixedOrderRecurrences ()
	Return the fixed-order recurrences found in the loop.

Type *	getWidestInductionType ()
	Returns the widest induction type.

bool	isInvariantStoreOfReduction (StoreInst *SI)
	Returns True if given store is a final invariant store of one of the reductions found in the loop.

bool	isInvariantAddressOfReduction (Value *V)
	Returns True if given address is invariant and is used to store recurrent expression.

bool	isInductionPhi (const Value *V) const
	Returns True if V is a Phi node of an induction variable in this loop.

const InductionDescriptor *	getIntOrFpInductionDescriptor (PHINode *Phi) const
	Returns a pointer to the induction descriptor, if `Phi` is an integer or floating point induction.

const InductionDescriptor *	getPointerInductionDescriptor (PHINode *Phi) const
	Returns a pointer to the induction descriptor, if `Phi` is pointer induction.

bool	isCastedInductionVariable (const Value *V) const
	Returns True if V is a cast that is part of an induction def-use chain, and had been proven to be redundant under a runtime guard (in other words, the cast has the same SCEV expression as the induction phi).

bool	isInductionVariable (const Value *V) const
	Returns True if V can be considered as an induction variable in this loop.

bool	isReductionVariable (PHINode *PN) const
	Returns True if PN is a reduction variable in this loop.

bool	isFixedOrderRecurrence (const PHINode *Phi) const
	Returns True if Phi is a fixed-order recurrence in this loop.

bool	blockNeedsPredication (BasicBlock *BB) const
	Return true if the block BB needs to be predicated in order for the loop to be vectorized.

int	isConsecutivePtr (Type AccessTy, Value Ptr) const
	Check if this pointer is consecutive when vectorizing.

bool	isInvariant (Value *V) const
	Returns true if `V` is invariant across all loop iterations according to SCEV.

bool	isUniform (Value *V, ElementCount VF) const
	Returns true if value V is uniform across `VF` lanes, when `VF` is provided, and otherwise if `V` is invariant across all loop iterations.

bool	isUniformMemOp (Instruction &I, ElementCount VF) const
	A uniform memory op is a load or store which accesses the same memory location on all `VF` lanes, if `VF` is provided and otherwise if the memory location is invariant.

const RuntimePointerChecking *	getRuntimePointerChecking () const
	Returns the information that we collected about runtime memory check.

const LoopAccessInfo *	getLAI () const

bool	isSafeForAnyVectorWidth () const

uint64_t	getMaxSafeVectorWidthInBits () const

bool	hasUncountableEarlyExit () const
	Returns true if the loop has an uncountable early exit, i.e.

BasicBlock *	getUncountableEarlyExitingBlock () const
	Returns the uncountable early exiting block.

BasicBlock *	getUncountableEarlyExitBlock () const
	Returns the destination of an uncountable early exiting block.

bool	isMaskRequired (const Instruction *I) const
	Returns true if vector representation of the instruction `I` requires mask.

bool	hasVectorCallVariants () const
	Returns true if there is at least one function call in the loop which has a vectorized variant available.

unsigned	getNumStores () const

unsigned	getNumLoads () const

std::optional< const HistogramInfo * >	getHistogramInfo (Instruction *I) const
	Returns a HistogramInfo* for the given instruction if it was determined to be part of a load -> update -> store sequence where multiple lanes may be working on the same memory address.

bool	hasHistograms () const
	Returns a list of all known histogram operations in the loop.

PredicatedScalarEvolution *	getPredicatedScalarEvolution () const

Loop *	getLoop () const

LoopInfo *	getLoopInfo () const

AssumptionCache *	getAssumptionCache () const

ScalarEvolution *	getScalarEvolution () const

DominatorTree *	getDominatorTree () const

const SmallVector< BasicBlock *, 4 > &	getCountableExitingBlocks () const
	Returns all exiting blocks with a countable exit, i.e.

const SmallVector< BasicBlock *, 4 > &	getUncountableExitingBlocks () const
	Returns all the exiting blocks with an uncountable exit.

SmallVector< BasicBlock *, 4 >	getUncountableExitBlocks () const
	Returns all the exit blocks from uncountable exiting blocks.

Detailed Description

LoopVectorizationLegality checks if it is legal to vectorize a loop, and to what vectorization factor.

This class does not look at the profitability of vectorization, only the legality. This class has two main kinds of checks:

Memory checks - The code in canVectorizeMemory checks if vectorization will change the order of memory accesses in a way that will change the correctness of the program.
Scalars checks - The code in canVectorizeInstrs and canVectorizeMemory checks for a number of different conditions, such as the availability of a single induction variable, that all types are supported and vectorize-able, etc. This code reflects the capabilities of InnerLoopVectorizer. This class is also used by InnerLoopVectorizer for identifying induction variable and the different reduction variables.

Definition at line 252 of file LoopVectorizationLegality.h.

Member Typedef Documentation

◆ InductionList

using llvm::LoopVectorizationLegality::InductionList = MapVector<PHINode *, InductionDescriptor>

InductionList saves induction variables and maps them to the induction descriptor.

Definition at line 270 of file LoopVectorizationLegality.h.

◆ RecurrenceSet

using llvm::LoopVectorizationLegality::RecurrenceSet = SmallPtrSet<const PHINode *, 8>

RecurrenceSet contains the phi nodes that are recurrences other than inductions and reductions.

Definition at line 274 of file LoopVectorizationLegality.h.

◆ ReductionList

using llvm::LoopVectorizationLegality::ReductionList = MapVector<PHINode *, RecurrenceDescriptor>

ReductionList contains the reduction descriptors for all of the reductions that were found in the loop.

Definition at line 266 of file LoopVectorizationLegality.h.

Constructor & Destructor Documentation

◆ LoopVectorizationLegality()

llvm::LoopVectorizationLegality::LoopVectorizationLegality	(	Loop *	L,
		PredicatedScalarEvolution &	PSE,
		DominatorTree *	DT,
		TargetTransformInfo *	TTI,
		TargetLibraryInfo *	TLI,
		Function *	F,
		LoopAccessInfoManager &	LAIs,
		LoopInfo *	LI,
		OptimizationRemarkEmitter *	ORE,
		LoopVectorizationRequirements *	R,
		LoopVectorizeHints *	H,
		DemandedBits *	DB,
		AssumptionCache *	AC,
		BlockFrequencyInfo *	BFI,
		ProfileSummaryInfo *	PSI
	)

inline

Definition at line 254 of file LoopVectorizationLegality.h.

Member Function Documentation

◆ blockNeedsPredication()

bool llvm::LoopVectorizationLegality::blockNeedsPredication ( BasicBlock * BB ) const

Return true if the block BB needs to be predicated in order for the loop to be vectorized.

Definition at line 1372 of file LoopVectorizationLegality.cpp.

References assert(), llvm::LoopAccessInfo::blockNeedsPredication(), llvm::LoopBase< BlockT, LoopT >::getLoopLatch(), getUncountableEarlyExitingBlock(), hasUncountableEarlyExit(), llvm::is_contained(), and llvm::predecessors().

Referenced by llvm::LoopVectorizationCostModel::blockNeedsPredicationForAnyReason(), llvm::LoopVectorizationCostModel::expectedCost(), llvm::LoopVectorizationCostModel::isPredicatedInst(), and isUniformMemOp().

◆ canFoldTailByMasking()

bool llvm::LoopVectorizationLegality::canFoldTailByMasking ( ) const

Return true if we can vectorize this loop while folding its tail by masking.

Definition at line 1838 of file LoopVectorizationLegality.cpp.

References llvm::LoopBase< BlockT, LoopT >::blocks(), llvm::LoopBase< BlockT, LoopT >::contains(), llvm::SmallPtrSetImpl< PtrType >::count(), llvm::dbgs(), getInductionVars(), getReductionVars(), llvm::SmallPtrSetImpl< PtrType >::insert(), LLVM_DEBUG, Reduction, and llvm::Value::users().

Referenced by llvm::LoopVectorizationCostModel::setTailFoldingStyles().

◆ canVectorize()

bool llvm::LoopVectorizationLegality::canVectorize ( bool UseVPlanNativePath )

Returns true if it is legal to vectorize this loop.

This does not mean that it is profitable to vectorize this loop, only that it is legal to do so. Temporarily taking UseVPlanNativePath parameter. If true, take the new code path being implemented for outer loop vectorization (should be functional for inner loop vectorization) based on VPlan. If false, good old LV code.

Definition at line 1727 of file LoopVectorizationLegality.cpp.

References llvm::OptimizationRemarkEmitter::allowExtraAnalysis(), assert(), llvm::dbgs(), DEBUG_TYPE, llvm::LoopVectorizeHints::FK_Enabled, llvm::PredicatedScalarEvolution::getBackedgeTakenCount(), llvm::SCEVPredicate::getComplexity(), llvm::LoopBase< BlockT, LoopT >::getHeader(), llvm::Value::getName(), llvm::LoopBase< BlockT, LoopT >::getNumBlocks(), llvm::PredicatedScalarEvolution::getPredicate(), llvm::LoopAccessInfo::getRuntimePointerChecking(), llvm::LoopBase< BlockT, LoopT >::isInnermost(), LLVM_DEBUG, llvm::RuntimePointerChecking::Need, PragmaVectorizeSCEVCheckThreshold, llvm::reportVectorizationFailure(), and VectorizeSCEVCheckThreshold.

Referenced by llvm::LoopVectorizePass::processLoop().

◆ canVectorizeFPMath()

bool llvm::LoopVectorizationLegality::canVectorizeFPMath ( bool EnableStrictReductions )

Returns true if it is legal to vectorize the FP math operations in this loop.

Vectorizing is legal if we allow reordering of FP operations, or if we can use in-order reductions.

Definition at line 1281 of file LoopVectorizationLegality.cpp.

References llvm::all_of(), llvm::any_of(), llvm::LoopVectorizationRequirements::getExactFPInst(), llvm::InductionDescriptor::getExactFPMathInst(), getInductionVars(), getReductionVars(), llvm::RecurrenceDescriptor::hasExactFPMath(), llvm::RecurrenceDescriptor::isOrdered(), and Reduction.

Referenced by llvm::LoopVectorizePass::processLoop().

◆ getAssumptionCache()

AssumptionCache * llvm::LoopVectorizationLegality::getAssumptionCache ( ) const

inline

Definition at line 450 of file LoopVectorizationLegality.h.

Referenced by llvm::ARMTTIImpl::preferPredicateOverEpilogue().

◆ getCountableExitingBlocks()

const SmallVector< BasicBlock *, 4 > & llvm::LoopVectorizationLegality::getCountableExitingBlocks ( ) const

inline

Returns all exiting blocks with a countable exit, i.e.

the exit-not-taken count is known exactly at compile time.

Definition at line 458 of file LoopVectorizationLegality.h.

Referenced by llvm::LoopVectorizePass::processLoop().

◆ getDominatorTree()

DominatorTree * llvm::LoopVectorizationLegality::getDominatorTree ( ) const

inline

Definition at line 454 of file LoopVectorizationLegality.h.

Referenced by llvm::ARMTTIImpl::preferPredicateOverEpilogue().

◆ getFixedOrderRecurrences()

RecurrenceSet & llvm::LoopVectorizationLegality::getFixedOrderRecurrences ( )

inline

Return the fixed-order recurrences found in the loop.

Definition at line 308 of file LoopVectorizationLegality.h.

Referenced by llvm::AArch64TTIImpl::preferPredicateOverEpilogue().

◆ getHistogramInfo()

std::optional< const HistogramInfo * > llvm::LoopVectorizationLegality::getHistogramInfo ( Instruction * I ) const

inline

Returns a HistogramInfo* for the given instruction if it was determined to be part of a load -> update -> store sequence where multiple lanes may be working on the same memory address.

Definition at line 431 of file LoopVectorizationLegality.h.

References I.

Referenced by llvm::LoopVectorizationCostModel::getInstructionCost(), and llvm::VPRecipeBuilder::tryToCreateWidenRecipe().

◆ getInductionVars()

const InductionList & llvm::LoopVectorizationLegality::getInductionVars ( ) const

inline

Returns the induction variables found in the loop.

Definition at line 305 of file LoopVectorizationLegality.h.

Referenced by canFoldTailByMasking(), canVectorizeFPMath(), llvm::LoopVectorizationCostModel::collectValuesToIgnore(), llvm::InnerLoopVectorizer::createInductionResumeVPValues(), llvm::LoopVectorizationPlanner::executePlan(), llvm::LoopVectorizationCostModel::expectedCost(), llvm::InnerLoopVectorizer::fixVectorizedLoop(), getIntOrFpInductionDescriptor(), and getPointerInductionDescriptor().

◆ getIntOrFpInductionDescriptor()

const InductionDescriptor * llvm::LoopVectorizationLegality::getIntOrFpInductionDescriptor ( PHINode * Phi ) const

Returns a pointer to the induction descriptor, if Phi is an integer or floating point induction.

Definition at line 1337 of file LoopVectorizationLegality.cpp.

References llvm::MapVector< KeyT, ValueT, MapType, VectorType >::find(), getInductionVars(), llvm::InductionDescriptor::IK_FpInduction, llvm::InductionDescriptor::IK_IntInduction, and isInductionPhi().

◆ getLAI()

const LoopAccessInfo * llvm::LoopVectorizationLegality::getLAI ( ) const

inline

Definition at line 382 of file LoopVectorizationLegality.h.

Referenced by llvm::LoopVectorizationPlanner::executePlan(), llvm::ARMTTIImpl::preferPredicateOverEpilogue(), llvm::LoopVectorizePass::processLoop(), processLoopInVPlanNativePath(), and llvm::LoopVectorizationCostModel::runtimeChecksRequired().

◆ getLoop()

Loop * llvm::LoopVectorizationLegality::getLoop ( ) const

inline

Definition at line 446 of file LoopVectorizationLegality.h.

Referenced by llvm::AArch64TTIImpl::preferPredicateOverEpilogue(), and llvm::ARMTTIImpl::preferPredicateOverEpilogue().

◆ getLoopInfo()

LoopInfo * llvm::LoopVectorizationLegality::getLoopInfo ( ) const

inline

Definition at line 448 of file LoopVectorizationLegality.h.

Referenced by llvm::ARMTTIImpl::preferPredicateOverEpilogue().

◆ getMaxSafeVectorWidthInBits()

uint64_t llvm::LoopVectorizationLegality::getMaxSafeVectorWidthInBits ( ) const

inline

Definition at line 388 of file LoopVectorizationLegality.h.

References llvm::LoopAccessInfo::getDepChecker(), and llvm::MemoryDepChecker::getMaxSafeVectorWidthInBits().

◆ getNumLoads()

unsigned llvm::LoopVectorizationLegality::getNumLoads ( ) const

inline

Definition at line 426 of file LoopVectorizationLegality.h.

References llvm::LoopAccessInfo::getNumLoads().

Referenced by llvm::LoopVectorizationCostModel::selectInterleaveCount().

◆ getNumStores()

unsigned llvm::LoopVectorizationLegality::getNumStores ( ) const

inline

Definition at line 425 of file LoopVectorizationLegality.h.

References llvm::LoopAccessInfo::getNumStores().

Referenced by llvm::LoopVectorizationCostModel::selectInterleaveCount().

◆ getPointerInductionDescriptor()

const InductionDescriptor * llvm::LoopVectorizationLegality::getPointerInductionDescriptor ( PHINode * Phi ) const

Returns a pointer to the induction descriptor, if Phi is pointer induction.

Definition at line 1348 of file LoopVectorizationLegality.cpp.

References llvm::MapVector< KeyT, ValueT, MapType, VectorType >::find(), getInductionVars(), llvm::InductionDescriptor::IK_PtrInduction, and isInductionPhi().

◆ getPredicatedScalarEvolution()

PredicatedScalarEvolution * llvm::LoopVectorizationLegality::getPredicatedScalarEvolution ( ) const

inline

Definition at line 442 of file LoopVectorizationLegality.h.

Referenced by llvm::AArch64TTIImpl::preferPredicateOverEpilogue().

◆ getPrimaryInduction()

PHINode * llvm::LoopVectorizationLegality::getPrimaryInduction ( )

inline

Returns the primary induction variable.

Definition at line 299 of file LoopVectorizationLegality.h.

Referenced by llvm::InnerLoopVectorizer::createInductionResumeVPValue(), and llvm::LoopVectorizationCostModel::isOptimizableIVTruncate().

◆ getReductionVars()

const ReductionList & llvm::LoopVectorizationLegality::getReductionVars ( ) const

inline

Returns the reduction variables found in the loop.

Definition at line 302 of file LoopVectorizationLegality.h.

◆ getRuntimePointerChecking()

const RuntimePointerChecking * llvm::LoopVectorizationLegality::getRuntimePointerChecking ( ) const

inline

Returns the information that we collected about runtime memory check.

Definition at line 378 of file LoopVectorizationLegality.h.

References llvm::LoopAccessInfo::getRuntimePointerChecking().

Referenced by llvm::LoopVectorizationCostModel::computeMaxVF(), llvm::LoopVectorizationCostModel::runtimeChecksRequired(), and llvm::LoopVectorizationCostModel::selectInterleaveCount().

◆ getScalarEvolution()

ScalarEvolution * llvm::LoopVectorizationLegality::getScalarEvolution ( ) const

inline

Definition at line 452 of file LoopVectorizationLegality.h.

References llvm::PredicatedScalarEvolution::getSE().

Referenced by llvm::ARMTTIImpl::preferPredicateOverEpilogue().

◆ getUncountableEarlyExitBlock()

BasicBlock * llvm::LoopVectorizationLegality::getUncountableEarlyExitBlock ( ) const

inline

Returns the destination of an uncountable early exiting block.

Definition at line 409 of file LoopVectorizationLegality.h.

References assert(), getUncountableExitBlocks(), and llvm::size().

◆ getUncountableEarlyExitingBlock()

BasicBlock * llvm::LoopVectorizationLegality::getUncountableEarlyExitingBlock ( ) const

inline

Returns the uncountable early exiting block.

Definition at line 397 of file LoopVectorizationLegality.h.

References assert(), getUncountableExitingBlocks(), and llvm::size().

Referenced by blockNeedsPredication(), and llvm::VPRecipeBuilder::createEdgeMask().

◆ getUncountableExitBlocks()

SmallVector< BasicBlock *, 4 > llvm::LoopVectorizationLegality::getUncountableExitBlocks ( ) const

inline

Returns all the exit blocks from uncountable exiting blocks.

Definition at line 468 of file LoopVectorizationLegality.h.

Referenced by getUncountableEarlyExitBlock().

◆ getUncountableExitingBlocks()

const SmallVector< BasicBlock *, 4 > & llvm::LoopVectorizationLegality::getUncountableExitingBlocks ( ) const

inline

Returns all the exiting blocks with an uncountable exit.

Definition at line 463 of file LoopVectorizationLegality.h.

Referenced by getUncountableEarlyExitingBlock().

◆ getWidestInductionType()

Type * llvm::LoopVectorizationLegality::getWidestInductionType ( )

inline

Returns the widest induction type.

Definition at line 311 of file LoopVectorizationLegality.h.

Referenced by llvm::LoopVectorizationPlanner::computeBestVF(), llvm::LoopVectorizationPlanner::emitInvalidCostRemarks(), llvm::LoopVectorizationPlanner::executePlan(), and llvm::LoopVectorizationPlanner::selectEpilogueVectorizationFactor().

◆ hasHistograms()

bool llvm::LoopVectorizationLegality::hasHistograms ( ) const

inline

Returns a list of all known histogram operations in the loop.

Definition at line 440 of file LoopVectorizationLegality.h.

Referenced by llvm::LoopVectorizePass::processLoop().

◆ hasUncountableEarlyExit()

bool llvm::LoopVectorizationLegality::hasUncountableEarlyExit ( ) const

inline

Returns true if the loop has an uncountable early exit, i.e.

an uncountable exit that isn't the latch block.

Definition at line 394 of file LoopVectorizationLegality.h.

Referenced by blockNeedsPredication(), llvm::LoopVectorizationPlanner::executePlan(), llvm::InnerLoopVectorizer::fixVectorizedLoop(), llvm::LoopVectorizePass::processLoop(), llvm::LoopVectorizationCostModel::requiresScalarEpilogue(), and llvm::LoopVectorizationCostModel::selectInterleaveCount().

◆ hasVectorCallVariants()

bool llvm::LoopVectorizationLegality::hasVectorCallVariants ( ) const

inline

Returns true if there is at least one function call in the loop which has a vectorized variant available.

Definition at line 423 of file LoopVectorizationLegality.h.

◆ isCastedInductionVariable()

bool llvm::LoopVectorizationLegality::isCastedInductionVariable ( const Value * V ) const

Returns True if V is a cast that is part of an induction def-use chain, and had been proven to be redundant under a runtime guard (in other words, the cast has the same SCEV expression as the induction phi).

Definition at line 1357 of file LoopVectorizationLegality.cpp.

References llvm::SmallPtrSetImpl< PtrType >::count().

Referenced by isInductionVariable().

◆ isConsecutivePtr()

int llvm::LoopVectorizationLegality::isConsecutivePtr	(	Type *	AccessTy,
		Value *	Ptr
	)		const

Check if this pointer is consecutive when vectorizing.

This happens when the last index of the GEP is the induction variable, or that the pointer itself is an induction variable. This check allows us to vectorize A[idx] into a wide load/store. Returns: 0 - Stride is unknown or non-consecutive. 1 - Address is consecutive. -1 - Address is consecutive, and decreasing. NOTE: This method must only be used before modifying the original scalar loop. Do not use after invoking 'createVectorizedLoopSkeleton' (PR34965).

Definition at line 454 of file LoopVectorizationLegality.cpp.

References llvm::LoopBase< BlockT, LoopT >::getHeader(), llvm::getPtrStride(), llvm::LoopAccessInfo::getSymbolicStrides(), llvm::IRPass, Ptr, and llvm::shouldOptimizeForSize().

Referenced by llvm::LoopVectorizationCostModel::isLegalMaskedLoad(), llvm::LoopVectorizationCostModel::isLegalMaskedStore(), llvm::LoopVectorizationCostModel::memoryInstructionCanBeWidened(), and llvm::LoopVectorizationCostModel::setCostBasedWideningDecision().

◆ isFixedOrderRecurrence()

bool llvm::LoopVectorizationLegality::isFixedOrderRecurrence ( const PHINode * Phi ) const

Returns True if Phi is a fixed-order recurrence in this loop.

Definition at line 1367 of file LoopVectorizationLegality.cpp.

References llvm::SmallPtrSetImpl< PtrType >::count().

Referenced by llvm::LoopVectorizationCostModel::getInstructionCost(), and llvm::VPRecipeBuilder::tryToCreateWidenRecipe().

◆ isInductionPhi()

bool llvm::LoopVectorizationLegality::isInductionPhi ( const Value * V ) const

Returns True if V is a Phi node of an induction variable in this loop.

Definition at line 1327 of file LoopVectorizationLegality.cpp.

References llvm::MapVector< KeyT, ValueT, MapType, VectorType >::count().

Referenced by getIntOrFpInductionDescriptor(), getPointerInductionDescriptor(), isInductionVariable(), and llvm::LoopVectorizationCostModel::isOptimizableIVTruncate().

◆ isInductionVariable()

bool llvm::LoopVectorizationLegality::isInductionVariable ( const Value * V ) const

Returns True if V can be considered as an induction variable in this loop.

V can be the induction phi, or some redundant cast in the def-use chain of the inducion phi.

Definition at line 1363 of file LoopVectorizationLegality.cpp.

References isCastedInductionVariable(), and isInductionPhi().

◆ isInvariant()

bool llvm::LoopVectorizationLegality::isInvariant ( Value * V ) const

Returns true if V is invariant across all loop iterations according to SCEV.

Definition at line 472 of file LoopVectorizationLegality.cpp.

References llvm::LoopAccessInfo::isInvariant().

Referenced by llvm::LoopVectorizationCostModel::getDivRemSpeculationCost(), llvm::LoopVectorizationCostModel::isPredicatedInst(), isUniform(), and llvm::LoopVectorizationCostModel::shouldConsiderInvariant().

◆ isInvariantAddressOfReduction()

bool llvm::LoopVectorizationLegality::isInvariantAddressOfReduction ( Value * V )

Returns True if given address is invariant and is used to store recurrent expression.

Definition at line 1314 of file LoopVectorizationLegality.cpp.

References llvm::any_of(), llvm::StoreInst::getPointerOperand(), getReductionVars(), llvm::ScalarEvolution::getSCEV(), llvm::PredicatedScalarEvolution::getSE(), llvm::RecurrenceDescriptor::IntermediateStore, and Reduction.

Referenced by llvm::LoopVectorizationCostModel::collectValuesToIgnore().

◆ isInvariantStoreOfReduction()

bool llvm::LoopVectorizationLegality::isInvariantStoreOfReduction ( StoreInst * SI )

Returns True if given store is a final invariant store of one of the reductions found in the loop.

Definition at line 1307 of file LoopVectorizationLegality.cpp.

References llvm::any_of(), getReductionVars(), llvm::RecurrenceDescriptor::IntermediateStore, and Reduction.

◆ isMaskRequired()

bool llvm::LoopVectorizationLegality::isMaskRequired ( const Instruction * I ) const

inline

Returns true if vector representation of the instruction I requires mask.

Definition at line 417 of file LoopVectorizationLegality.h.

References I.

Referenced by llvm::LoopVectorizationCostModel::getInstructionCost(), llvm::LoopVectorizationCostModel::interleavedAccessCanBeWidened(), llvm::LoopVectorizationCostModel::isPredicatedInst(), and llvm::LoopVectorizationCostModel::setVectorizedCallDecision().

◆ isReductionVariable()

bool llvm::LoopVectorizationLegality::isReductionVariable ( PHINode * PN ) const

inline

Returns True if PN is a reduction variable in this loop.

Definition at line 343 of file LoopVectorizationLegality.h.

References llvm::MapVector< KeyT, ValueT, MapType, VectorType >::count().

Referenced by llvm::LoopVectorizationCostModel::collectElementTypesForWidening(), and llvm::VPRecipeBuilder::tryToCreateWidenRecipe().

◆ isSafeForAnyVectorWidth()

bool llvm::LoopVectorizationLegality::isSafeForAnyVectorWidth ( ) const

inline

Definition at line 384 of file LoopVectorizationLegality.h.

References llvm::LoopAccessInfo::getDepChecker(), and llvm::MemoryDepChecker::isSafeForAnyVectorWidth().

Referenced by llvm::LoopVectorizationCostModel::selectInterleaveCount().

◆ isUniform()

bool llvm::LoopVectorizationLegality::isUniform	(	Value *	V,
		ElementCount	VF
	)		const

Returns true if value V is uniform across VF lanes, when VF is provided, and otherwise if V is invariant across all loop iterations.

Definition at line 567 of file LoopVectorizationLegality.cpp.

References llvm::all_of(), llvm::details::FixedOrScalableQuantity< LeafTy, ValueTy >::getKnownMinValue(), llvm::ScalarEvolution::getSCEV(), llvm::PredicatedScalarEvolution::getSE(), I, isInvariant(), llvm::details::FixedOrScalableQuantity< LeafTy, ValueTy >::isScalable(), llvm::ElementCount::isScalar(), llvm::ScalarEvolution::isSCEVable(), and llvm::reverse().

Referenced by isUniformMemOp().

◆ isUniformMemOp()

bool llvm::LoopVectorizationLegality::isUniformMemOp	(	Instruction &	I,
		ElementCount	VF
	)		const

A uniform memory op is a load or store which accesses the same memory location on all VF lanes, if VF is provided and otherwise if the memory location is invariant.

Definition at line 600 of file LoopVectorizationLegality.cpp.

References blockNeedsPredication(), llvm::getLoadStorePointerOperand(), I, isUniform(), and Ptr.

Referenced by llvm::LoopVectorizationCostModel::setCostBasedWideningDecision().

◆ prepareToFoldTailByMasking()

void llvm::LoopVectorizationLegality::prepareToFoldTailByMasking ( )

Mark all respective loads/stores for masking.

Must only be called when tail-folding is possible.

Definition at line 1896 of file LoopVectorizationLegality.cpp.

References assert(), and llvm::LoopBase< BlockT, LoopT >::blocks().

Referenced by llvm::LoopVectorizationPlanner::plan().

The documentation for this class was generated from the following files:

include/llvm/Transforms/Vectorize/LoopVectorizationLegality.h
lib/Transforms/Vectorize/LoopVectorizationLegality.cpp

Public Types

Public Member Functions

Detailed Description

Member Typedef Documentation

◆ InductionList

◆ RecurrenceSet

◆ ReductionList

Constructor & Destructor Documentation

◆ LoopVectorizationLegality()

Member Function Documentation

◆ blockNeedsPredication()

◆ canFoldTailByMasking()

◆ canVectorize()

◆ canVectorizeFPMath()

◆ getAssumptionCache()

◆ getCountableExitingBlocks()

◆ getDominatorTree()

◆ getFixedOrderRecurrences()

◆ getHistogramInfo()

◆ getInductionVars()

◆ getIntOrFpInductionDescriptor()

◆ getLAI()

◆ getLoop()

◆ getLoopInfo()

◆ getMaxSafeVectorWidthInBits()

◆ getNumLoads()

◆ getNumStores()

◆ getPointerInductionDescriptor()

◆ getPredicatedScalarEvolution()

◆ getPrimaryInduction()

◆ getReductionVars()

◆ getRuntimePointerChecking()

◆ getScalarEvolution()

◆ getUncountableEarlyExitBlock()

◆ getUncountableEarlyExitingBlock()

◆ getUncountableExitBlocks()

◆ getUncountableExitingBlocks()

◆ getWidestInductionType()

◆ hasHistograms()

◆ hasUncountableEarlyExit()

◆ hasVectorCallVariants()

◆ isCastedInductionVariable()

◆ isConsecutivePtr()

◆ isFixedOrderRecurrence()

◆ isInductionPhi()

◆ isInductionVariable()

◆ isInvariant()

◆ isInvariantAddressOfReduction()

◆ isInvariantStoreOfReduction()

◆ isMaskRequired()

◆ isReductionVariable()

◆ isSafeForAnyVectorWidth()

◆ isUniform()

◆ isUniformMemOp()

◆ prepareToFoldTailByMasking()