A struct for saving information about induction variables. More...

#include "llvm/Analysis/IVDescriptors.h"

Public Types
enum	InductionKind { IK_NoInduction, IK_IntInduction, IK_PtrInduction, IK_FpInduction }
	This enum represents the kinds of inductions that we support. More...

Public Member Functions
	InductionDescriptor ()=default
	Default constructor - creates an invalid induction. More...

int	getConsecutiveDirection () const
	Get the consecutive direction. More...

Value *	getStartValue () const

InductionKind	getKind () const

const SCEV *	getStep () const

BinaryOperator *	getInductionBinOp () const

ConstantInt *	getConstIntStepValue () const

bool	hasUnsafeAlgebra ()
	Returns true if the induction type is FP and the binary operator does not have the "fast-math" property. More...

Instruction *	getUnsafeAlgebraInst ()
	Returns induction operator that does not have "fast-math" property and requires FP unsafe mode. More...

Instruction::BinaryOps	getInductionOpcode () const
	Returns binary opcode of the induction operator. More...

const SmallVectorImpl< Instruction * > &	getCastInsts () const
	Returns a reference to the type cast instructions in the induction update chain, that are redundant when guarded with a runtime SCEV overflow check. More...

Static Public Member Functions
static bool	isInductionPHI (PHINode Phi, const Loop L, ScalarEvolution SE, InductionDescriptor &D, const SCEV Expr=nullptr, SmallVectorImpl< Instruction > CastsToIgnore=nullptr)
	Returns true if `Phi` is an induction in the loop `L`. More...

static bool	isFPInductionPHI (PHINode Phi, const Loop L, ScalarEvolution *SE, InductionDescriptor &D)
	Returns true if `Phi` is a floating point induction in the loop `L`. More...

static bool	isInductionPHI (PHINode Phi, const Loop L, PredicatedScalarEvolution &PSE, InductionDescriptor &D, bool Assume=false)
	Returns true if `Phi` is a loop `L` induction, in the context associated with the run-time predicate of PSE. More...

Detailed Description

A struct for saving information about induction variables.

Definition at line 254 of file IVDescriptors.h.

Member Enumeration Documentation

◆ InductionKind

enum llvm::InductionDescriptor::InductionKind

This enum represents the kinds of inductions that we support.

Enumerator
IK_NoInduction	Not an induction variable.
IK_IntInduction	Integer induction variable. Step = C.
IK_PtrInduction	Pointer induction var. Step = C / sizeof(elem).
IK_FpInduction	Floating point induction variable.

Definition at line 257 of file IVDescriptors.h.

Constructor & Destructor Documentation

◆ InductionDescriptor()

llvm::InductionDescriptor::InductionDescriptor ( )

default

Default constructor - creates an invalid induction.

Referenced by llvm::RecurrenceDescriptor::getRecurrenceBinOp().

Member Function Documentation

◆ getCastInsts()

const SmallVectorImpl<Instruction *>& llvm::InductionDescriptor::getCastInsts ( ) const

inline

Returns a reference to the type cast instructions in the induction update chain, that are redundant when guarded with a runtime SCEV overflow check.

Definition at line 332 of file IVDescriptors.h.

Referenced by llvm::LoopVectorizationPlanner::collectTriviallyDeadInstructions(), llvm::LoopVectorizationCostModel::collectValuesToIgnore(), llvm::LoopVectorizationLegality::isUniform(), and llvm::InnerLoopVectorizer::recordVectorLoopValueForInductionCast().

◆ getConsecutiveDirection()

int InductionDescriptor::getConsecutiveDirection ( ) const

Get the consecutive direction.

Returns: 0 - unknown or non-consecutive. 1 - consecutive and increasing. -1 - consecutive and decreasing.

Definition at line 809 of file IVDescriptors.cpp.

References llvm::ConstantInt::getSExtValue(), llvm::ConstantInt::isMinusOne(), and llvm::ConstantInt::isOne().

◆ getConstIntStepValue()

ConstantInt * InductionDescriptor::getConstIntStepValue ( ) const

Definition at line 816 of file IVDescriptors.cpp.

References llvm::dyn_cast().

Referenced by llvm::InnerLoopVectorizer::emitTransformedIndex(), and llvm::LoopVectorizationLegality::isUniform().

◆ getInductionBinOp()

BinaryOperator* llvm::InductionDescriptor::getInductionBinOp ( ) const

inline

Definition at line 277 of file IVDescriptors.h.

References D.

Referenced by llvm::InnerLoopVectorizer::emitTransformedIndex().

◆ getInductionOpcode()

Instruction::BinaryOps llvm::InductionDescriptor::getInductionOpcode ( ) const

inline

Returns binary opcode of the induction operator.

Definition at line 324 of file IVDescriptors.h.

Referenced by llvm::InnerLoopVectorizer::buildScalarSteps().

◆ getKind()

InductionKind llvm::InductionDescriptor::getKind ( ) const

inline

Definition at line 275 of file IVDescriptors.h.

Referenced by llvm::InnerLoopVectorizer::emitTransformedIndex(), llvm::LoopVectorizationLegality::isUniform(), llvm::VPRecipeBuilder::tryToOptimizeInduction(), and llvm::VPlanHCFGTransforms::VPInstructionsToVPRecipes().

◆ getStartValue()

Value* llvm::InductionDescriptor::getStartValue ( ) const

inline

Definition at line 274 of file IVDescriptors.h.

Referenced by llvm::InnerLoopVectorizer::createVectorizedLoopSkeleton(), llvm::InnerLoopVectorizer::emitTransformedIndex(), and llvm::LoopVectorizationLegality::isUniform().

◆ getStep()

const SCEV* llvm::InductionDescriptor::getStep ( ) const

inline

Definition at line 276 of file IVDescriptors.h.

Referenced by llvm::InnerLoopVectorizer::createVectorizedLoopSkeleton(), llvm::InnerLoopVectorizer::emitTransformedIndex(), and llvm::InnerLoopVectorizer::fixupIVUsers().

◆ getUnsafeAlgebraInst()

Instruction* llvm::InductionDescriptor::getUnsafeAlgebraInst ( )

inline

Returns induction operator that does not have "fast-math" property and requires FP unsafe mode.

Definition at line 317 of file IVDescriptors.h.

Referenced by llvm::LoopVectorizationLegality::isUniform().

◆ hasUnsafeAlgebra()

bool llvm::InductionDescriptor::hasUnsafeAlgebra ( )

inline

Returns true if the induction type is FP and the binary operator does not have the "fast-math" property.

Such operation requires a relaxed FP mode.

Definition at line 311 of file IVDescriptors.h.

Referenced by llvm::LoopVectorizationLegality::isUniform().

◆ isFPInductionPHI()

bool InductionDescriptor::isFPInductionPHI	(	PHINode *	Phi,
		const Loop *	L,
		ScalarEvolution *	SE,
		InductionDescriptor &	D
	)

static

Returns true if Phi is a floating point induction in the loop L.

If Phi is an induction, the induction descriptor D will contain the data describing this induction.

Definition at line 822 of file IVDescriptors.cpp.

References assert(), llvm::LoopBase< BlockT, LoopT >::contains(), llvm::dyn_cast(), llvm::LoopBase< BlockT, LoopT >::getHeader(), llvm::PHINode::getIncomingBlock(), llvm::PHINode::getIncomingValue(), llvm::PHINode::getNumIncomingValues(), llvm::BinaryOperator::getOpcode(), llvm::User::getOperand(), llvm::Instruction::getParent(), llvm::Value::getType(), llvm::ScalarEvolution::getUnknown(), I, and llvm::Type::isFloatingPointTy().

◆ isInductionPHI() [1/2]

bool InductionDescriptor::isInductionPHI	(	PHINode *	Phi,
		const Loop *	L,
		ScalarEvolution *	SE,
		InductionDescriptor &	D,
		const SCEV *	Expr = `nullptr`,
		SmallVectorImpl< Instruction >	CastsToIgnore = `nullptr`
	)

static

Returns true if Phi is an induction in the loop L.

If Phi is an induction, the induction descriptor D will contain the data describing this induction. If by some other means the caller has a better SCEV expression for Phi than the one returned by the ScalarEvolution analysis, it can be passed through Expr. If the def-use chain associated with the phi includes casts (that we know we can ignore under proper runtime checks), they are passed through CastsToIgnore.

Definition at line 1024 of file IVDescriptors.cpp.

References assert(), llvm::dbgs(), llvm::dyn_cast(), llvm::ScalarEvolution::getConstant(), llvm::Module::getDataLayout(), llvm::PHINode::getIncomingValueForBlock(), llvm::SCEVAddRecExpr::getLoop(), llvm::LoopBase< BlockT, LoopT >::getLoopPreheader(), llvm::Instruction::getModule(), llvm::Type::getPointerElementType(), llvm::ScalarEvolution::getSCEV(), llvm::ConstantInt::getSExtValue(), llvm::SCEVAddRecExpr::getStepRecurrence(), llvm::ConstantInt::getType(), llvm::Value::getType(), llvm::DataLayout::getTypeAllocSize(), llvm::SCEVConstant::getValue(), llvm::Type::isIntegerTy(), llvm::ScalarEvolution::isLoopInvariant(), llvm::Type::isPointerTy(), llvm::Type::isSized(), LLVM_DEBUG, and Size.

Referenced by findInnerReductionPhi(), and llvm::LoopVectorizationLegality::isUniform().

◆ isInductionPHI() [2/2]

bool InductionDescriptor::isInductionPHI	(	PHINode *	Phi,
		const Loop *	L,
		PredicatedScalarEvolution &	PSE,
		InductionDescriptor &	D,
		bool	Assume = `false`
	)

static

Returns true if Phi is a loop L induction, in the context associated with the run-time predicate of PSE.

If Assume is true, this can add further SCEV predicates to PSE in order to prove that Phi is an induction. If Phi is an induction, D will contain the data describing this induction.

Definition at line 980 of file IVDescriptors.cpp.

References D, llvm::dbgs(), llvm::dyn_cast(), llvm::PredicatedScalarEvolution::getAsAddRec(), getCastsForInductionPHI(), llvm::PredicatedScalarEvolution::getSCEV(), llvm::PredicatedScalarEvolution::getSE(), llvm::Value::getType(), llvm::Type::isDoubleTy(), llvm::Type::isFloatingPointTy(), llvm::Type::isFloatTy(), llvm::Type::isHalfTy(), llvm::Type::isIntegerTy(), llvm::Type::isPointerTy(), and LLVM_DEBUG.

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

include/llvm/Analysis/IVDescriptors.h
lib/Analysis/IVDescriptors.cpp

Public Types

Public Member Functions

Static Public Member Functions

Detailed Description

Member Enumeration Documentation

◆ InductionKind

Constructor & Destructor Documentation

◆ InductionDescriptor()

Member Function Documentation

◆ getCastInsts()

◆ getConsecutiveDirection()

◆ getConstIntStepValue()

◆ getInductionBinOp()

◆ getInductionOpcode()

◆ getKind()

◆ getStartValue()

◆ getStep()

◆ getUnsafeAlgebraInst()

◆ hasUnsafeAlgebra()

◆ isFPInductionPHI()

◆ isInductionPHI() [1/2]

◆ isInductionPHI() [2/2]