llvm::ScalarEvolution::ExitLimit Struct Reference

Information about the number of loop iterations for which a loop exit's branch condition evaluates to the not-taken path. More...

#include "llvm/Analysis/ScalarEvolution.h"

Public Member Functions
void	addPredicate (const SCEVPredicate *P)
	ExitLimit (const SCEV *E)
	Construct either an exact exit limit from a constant, or an unknown one from a SCEVCouldNotCompute.
	ExitLimit (const SCEV *E, const SCEV *ConstantMaxNotTaken, const SCEV *SymbolicMaxNotTaken, bool MaxOrZero, ArrayRef< const SmallPtrSetImpl< const SCEVPredicate * > * > PredSetList=std::nullopt)
	ExitLimit (const SCEV *E, const SCEV *ConstantMaxNotTaken, const SCEV *SymbolicMaxNotTaken, bool MaxOrZero, const SmallPtrSetImpl< const SCEVPredicate * > &PredSet)
bool	hasAnyInfo () const
	Test whether this ExitLimit contains any computed information, or whether it's all SCEVCouldNotCompute values.
bool	hasFullInfo () const
	Test whether this ExitLimit contains all information.

Public Attributes
const SCEV *	ExactNotTaken
const SCEV *	ConstantMaxNotTaken
const SCEV *	SymbolicMaxNotTaken
bool	MaxOrZero = false
SmallPtrSet< const SCEVPredicate *, 4 >	Predicates
	A set of predicate guards for this ExitLimit.

Detailed Description

Information about the number of loop iterations for which a loop exit's branch condition evaluates to the not-taken path.

This is a temporary pair of exact and max expressions that are eventually summarized in ExitNotTakenInfo and BackedgeTakenInfo.

Definition at line 1096 of file ScalarEvolution.h.

Constructor & Destructor Documentation

ExitLimit() [1/3]

ScalarEvolution::ExitLimit::ExitLimit

(

const SCEV *

E

)

Construct either an exact exit limit from a constant, or an unknown one from a SCEVCouldNotCompute.

No other types of SCEVs are allowed as arguments and asserts enforce that internally.

Definition at line 8663 of file ScalarEvolution.cpp.

ExitLimit() [2/3]

ScalarEvolution::ExitLimit::ExitLimit	(	const SCEV *	E,
		const SCEV *	ConstantMaxNotTaken,
		const SCEV *	SymbolicMaxNotTaken,
		bool	MaxOrZero,
		ArrayRef< const SmallPtrSetImpl< const SCEVPredicate * > * >	PredSetList = std::nullopt
	)

Definition at line 8666 of file ScalarEvolution.cpp.

References addPredicate(), assert(), ConstantMaxNotTaken, ExactNotTaken, llvm::SCEV::getType(), llvm::Type::isPointerTy(), llvm::SCEV::isZero(), P, and SymbolicMaxNotTaken.

ExitLimit() [3/3]

ScalarEvolution::ExitLimit::ExitLimit	(	const SCEV *	E,
		const SCEV *	ConstantMaxNotTaken,
		const SCEV *	SymbolicMaxNotTaken,
		bool	MaxOrZero,
		const SmallPtrSetImpl< const SCEVPredicate * > &	PredSet
	)

Definition at line 8702 of file ScalarEvolution.cpp.

Member Function Documentation

addPredicate()

void llvm::ScalarEvolution::ExitLimit::addPredicate ( const SCEVPredicate *  P )

inline

Definition at line 1110 of file ScalarEvolution.h.

References assert(), P, and Predicates.

Referenced by ExitLimit().

hasAnyInfo()

bool llvm::ScalarEvolution::ExitLimit::hasAnyInfo ( ) const

inline

Test whether this ExitLimit contains any computed information, or whether it's all SCEVCouldNotCompute values.

Definition at line 1132 of file ScalarEvolution.h.

References ConstantMaxNotTaken, and ExactNotTaken.

hasFullInfo()

bool llvm::ScalarEvolution::ExitLimit::hasFullInfo ( ) const

inline

Test whether this ExitLimit contains all information.

Definition at line 1138 of file ScalarEvolution.h.

References ExactNotTaken.

Member Data Documentation

ConstantMaxNotTaken

const SCEV* llvm::ScalarEvolution::ExitLimit::ConstantMaxNotTaken

Definition at line 1098 of file ScalarEvolution.h.

Referenced by ExitLimit(), and hasAnyInfo().

ExactNotTaken

const SCEV* llvm::ScalarEvolution::ExitLimit::ExactNotTaken

Definition at line 1097 of file ScalarEvolution.h.

Referenced by ExitLimit(), hasAnyInfo(), and hasFullInfo().

MaxOrZero

bool llvm::ScalarEvolution::ExitLimit::MaxOrZero = false

Definition at line 1103 of file ScalarEvolution.h.

Predicates

SmallPtrSet<const SCEVPredicate *, 4> llvm::ScalarEvolution::ExitLimit::Predicates

A set of predicate guards for this ExitLimit.

The result is only valid if all of the predicates in Predicates evaluate to 'true' at run-time.

Definition at line 1108 of file ScalarEvolution.h.

Referenced by addPredicate().

SymbolicMaxNotTaken

const SCEV* llvm::ScalarEvolution::ExitLimit::SymbolicMaxNotTaken

Definition at line 1100 of file ScalarEvolution.h.

Referenced by ExitLimit(), and optimizeLoopExitWithUnknownExitCount().

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

• include/llvm/Analysis/ScalarEvolution.h
• lib/Analysis/ScalarEvolution.cpp