Dependence - This class represents a dependence between two memory memory references in a function. More...

#include "llvm/Analysis/DependenceAnalysis.h"

Inheritance diagram for llvm::Dependence:

Classes
struct	DVEntry
	Dependence::DVEntry - Each level in the distance/direction vector has a direction (or perhaps a union of several directions), and perhaps a distance. More...

Public Member Functions
	Dependence (Instruction Source, Instruction Destination, const SCEVUnionPredicate &A)
virtual	~Dependence ()=default
Instruction *	getSrc () const
	getSrc - Returns the source instruction for this dependence.
Instruction *	getDst () const
	getDst - Returns the destination instruction for this dependence.
bool	isInput () const
	isInput - Returns true if this is an input dependence.
bool	isOutput () const
	isOutput - Returns true if this is an output dependence.
bool	isFlow () const
	isFlow - Returns true if this is a flow (aka true) dependence.
bool	isAnti () const
	isAnti - Returns true if this is an anti dependence.
bool	isOrdered () const
	isOrdered - Returns true if dependence is Output, Flow, or Anti
bool	isUnordered () const
	isUnordered - Returns true if dependence is Input
virtual bool	isLoopIndependent () const
	isLoopIndependent - Returns true if this is a loop-independent dependence.
virtual bool	isConfused () const
	isConfused - Returns true if this dependence is confused (the compiler understands nothing and makes worst-case assumptions).
virtual bool	isConsistent () const
	isConsistent - Returns true if this dependence is consistent (occurs every time the source and destination are executed).
virtual unsigned	getLevels () const
	getLevels - Returns the number of common loops surrounding the source and destination of the dependence.
virtual unsigned	getSameSDLevels () const
	getSameSDLevels - Returns the number of separate SameSD loops surrounding the source and destination of the dependence.
DVEntry	getDVEntry (unsigned Level, bool IsSameSD) const
	getDVEntry - Returns the DV entry associated with a regular or a SameSD level
virtual unsigned	getDirection (unsigned Level, bool SameSD=false) const
	getDirection - Returns the direction associated with a particular common or SameSD level.
virtual const SCEV *	getDistance (unsigned Level, bool SameSD=false) const
	getDistance - Returns the distance (or NULL) associated with a particular common or SameSD level.
virtual bool	isDirectionNegative () const
	Check if the direction vector is negative.
virtual bool	normalize (ScalarEvolution *SE)
	If the direction vector is negative, normalize the direction vector to make it non-negative.
virtual bool	isPeelFirst (unsigned Level, bool SameSD=false) const
	isPeelFirst - Returns true if peeling the first iteration from this regular or SameSD loop level will break this dependence.
virtual bool	isPeelLast (unsigned Level, bool SameSD=false) const
	isPeelLast - Returns true if peeling the last iteration from this regular or SameSD loop level will break this dependence.
virtual bool	isSplitable (unsigned Level, bool SameSD=false) const
	isSplitable - Returns true if splitting the loop will break the dependence.
virtual bool	inSameSDLoops (unsigned Level) const
	inSameSDLoops - Returns true if this level is an SameSD level, i.e., performed across two separate loop nests that have the Same Iteration and Depth.
virtual bool	isScalar (unsigned Level, bool SameSD=false) const
	isScalar - Returns true if a particular regular or SameSD level is scalar; that is, if no subscript in the source or destination mention the induction variable associated with the loop at this level.
const Dependence *	getNextPredecessor () const
	getNextPredecessor - Returns the value of the NextPredecessor field.
const Dependence *	getNextSuccessor () const
	getNextSuccessor - Returns the value of the NextSuccessor field.
void	setNextPredecessor (const Dependence *pred)
	setNextPredecessor - Sets the value of the NextPredecessor field.
void	setNextSuccessor (const Dependence *succ)
	setNextSuccessor - Sets the value of the NextSuccessor field.
SCEVUnionPredicate	getRuntimeAssumptions () const
	getRuntimeAssumptions - Returns the runtime assumptions under which this Dependence relation is valid.
void	dump (raw_ostream &OS) const
	dump - For debugging purposes, dumps a dependence to OS.
void	dumpImp (raw_ostream &OS, bool IsSameSD=false) const
	dumpImp - For debugging purposes.

Protected Member Functions
	Dependence (Dependence &&)=default
Dependence &	operator= (Dependence &&)=default

Protected Attributes
Instruction *	Src
Instruction *	Dst

Friends
class	DependenceInfo

Detailed Description

Dependence - This class represents a dependence between two memory memory references in a function.

It contains minimal information and is used in the very common situation where the compiler is unable to determine anything beyond the existence of a dependence; that is, it represents a confused dependence (see also FullDependence). In most cases (for output, flow, and anti dependences), the dependence implies an ordering, where the source must precede the destination; in contrast, input dependences are unordered.

When a dependence graph is built, each Dependence will be a member of the set of predecessor edges for its destination instruction and a set if successor edges for its source instruction. These sets are represented as singly-linked lists, with the "next" fields stored in the dependence itelf.

Definition at line 71 of file DependenceAnalysis.h.

Constructor & Destructor Documentation

◆ Dependence() [1/2]

llvm::Dependence::Dependence ( Dependence && )

protecteddefault

References Dependence().

Referenced by Dependence(), llvm::FullDependence::FullDependence(), getNextPredecessor(), getNextSuccessor(), operator=(), setNextPredecessor(), and setNextSuccessor().

◆ Dependence() [2/2]

llvm::Dependence::Dependence	(	Instruction *	Source,
		Instruction *	Destination,
		const SCEVUnionPredicate &	A )

inline

Definition at line 77 of file DependenceAnalysis.h.

References A(), Dst, and Src.

◆ ~Dependence()

virtual llvm::Dependence::~Dependence ( )

virtualdefault

Member Function Documentation

◆ dump()

void Dependence::dump ( raw_ostream & OS ) const

dump - For debugging purposes, dumps a dependence to OS.

Definition at line 986 of file DependenceAnalysis.cpp.

References dumpImp(), getRuntimeAssumptions(), getSameSDLevels(), isAnti(), isConfused(), isConsistent(), isFlow(), isInput(), and isOutput().

Referenced by llvm::FullDependence::normalize().

◆ dumpImp()

void Dependence::dumpImp	(	raw_ostream &	OS,
		bool	IsSameSD = false ) const

dumpImp - For debugging purposes.

Dumps a dependence to OS with or without considering the SameSD levels.

Definition at line 1018 of file DependenceAnalysis.cpp.

References llvm::Dependence::DVEntry::ALL, llvm::Dependence::DVEntry::EQ, getDirection(), getDistance(), getLevels(), getSameSDLevels(), llvm::Dependence::DVEntry::GT, II, inSameSDLoops(), isLoopIndependent(), isPeelFirst(), isPeelLast(), isScalar(), isSplitable(), and llvm::Dependence::DVEntry::LT.

Referenced by dump().

◆ getDirection()

virtual unsigned llvm::Dependence::getDirection	(	unsigned	Level,
		bool	SameSD = false ) const

inlinevirtual

getDirection - Returns the direction associated with a particular common or SameSD level.

Reimplemented in llvm::FullDependence.

Definition at line 167 of file DependenceAnalysis.h.

References llvm::Dependence::DVEntry::ALL.

Referenced by dumpImp().

◆ getDistance()

virtual const SCEV * llvm::Dependence::getDistance	(	unsigned	Level,
		bool	SameSD = false ) const

inlinevirtual

getDistance - Returns the distance (or NULL) associated with a particular common or SameSD level.

Reimplemented in llvm::FullDependence.

Definition at line 173 of file DependenceAnalysis.h.

Referenced by dumpImp().

◆ getDst()

Instruction * llvm::Dependence::getDst ( ) const

inline

getDst - Returns the destination instruction for this dependence.

Definition at line 121 of file DependenceAnalysis.h.

References Dst.

Referenced by llvm::DependenceInfo::getSplitIteration().

◆ getDVEntry()

DVEntry llvm::Dependence::getDVEntry	(	unsigned	Level,
		bool	IsSameSD ) const

getDVEntry - Returns the DV entry associated with a regular or a SameSD level

◆ getLevels()

virtual unsigned llvm::Dependence::getLevels ( ) const

inlinevirtual

getLevels - Returns the number of common loops surrounding the source and destination of the dependence.

Reimplemented in llvm::FullDependence.

Definition at line 155 of file DependenceAnalysis.h.

Referenced by dumpImp().

◆ getNextPredecessor()

const Dependence * llvm::Dependence::getNextPredecessor ( ) const

inline

getNextPredecessor - Returns the value of the NextPredecessor field.

Definition at line 216 of file DependenceAnalysis.h.

References Dependence().

◆ getNextSuccessor()

const Dependence * llvm::Dependence::getNextSuccessor ( ) const

inline

getNextSuccessor - Returns the value of the NextSuccessor field.

Definition at line 219 of file DependenceAnalysis.h.

References Dependence().

◆ getRuntimeAssumptions()

SCEVUnionPredicate llvm::Dependence::getRuntimeAssumptions ( ) const

inline

getRuntimeAssumptions - Returns the runtime assumptions under which this Dependence relation is valid.

Definition at line 230 of file DependenceAnalysis.h.

Referenced by dump().

◆ getSameSDLevels()

virtual unsigned llvm::Dependence::getSameSDLevels ( ) const

inlinevirtual

getSameSDLevels - Returns the number of separate SameSD loops surrounding the source and destination of the dependence.

Reimplemented in llvm::FullDependence.

Definition at line 159 of file DependenceAnalysis.h.

Referenced by dump(), and dumpImp().

◆ getSrc()

Instruction * llvm::Dependence::getSrc ( ) const

inline

getSrc - Returns the source instruction for this dependence.

Definition at line 118 of file DependenceAnalysis.h.

References Src.

Referenced by llvm::DependenceInfo::getSplitIteration().

◆ inSameSDLoops()

virtual bool llvm::Dependence::inSameSDLoops ( unsigned Level ) const

inlinevirtual

inSameSDLoops - Returns true if this level is an SameSD level, i.e., performed across two separate loop nests that have the Same Iteration and Depth.

Reimplemented in llvm::FullDependence.

Definition at line 208 of file DependenceAnalysis.h.

Referenced by dumpImp().

◆ isAnti()

bool Dependence::isAnti ( ) const

isAnti - Returns true if this is an anti dependence.

Definition at line 504 of file DependenceAnalysis.cpp.

References Dst, and Src.

Referenced by dump(), and isOrdered().

◆ isConfused()

virtual bool llvm::Dependence::isConfused ( ) const

inlinevirtual

isConfused - Returns true if this dependence is confused (the compiler understands nothing and makes worst-case assumptions).

Reimplemented in llvm::FullDependence.

Definition at line 147 of file DependenceAnalysis.h.

Referenced by dump().

◆ isConsistent()

virtual bool llvm::Dependence::isConsistent ( ) const

inlinevirtual

isConsistent - Returns true if this dependence is consistent (occurs every time the source and destination are executed).

Reimplemented in llvm::FullDependence.

Definition at line 151 of file DependenceAnalysis.h.

Referenced by dump().

◆ isDirectionNegative()

virtual bool llvm::Dependence::isDirectionNegative ( ) const

inlinevirtual

Check if the direction vector is negative.

A negative direction vector means Src and Dst are reversed in the actual program.

Reimplemented in llvm::FullDependence.

Definition at line 179 of file DependenceAnalysis.h.

◆ isFlow()

bool Dependence::isFlow ( ) const

isFlow - Returns true if this is a flow (aka true) dependence.

Definition at line 499 of file DependenceAnalysis.cpp.

References Dst, and Src.

Referenced by dump(), and isOrdered().

◆ isInput()

bool Dependence::isInput ( ) const

isInput - Returns true if this is an input dependence.

Definition at line 489 of file DependenceAnalysis.cpp.

References Dst, and Src.

Referenced by dump().

◆ isLoopIndependent()

virtual bool llvm::Dependence::isLoopIndependent ( ) const

inlinevirtual

isLoopIndependent - Returns true if this is a loop-independent dependence.

Reimplemented in llvm::FullDependence.

Definition at line 143 of file DependenceAnalysis.h.

Referenced by dumpImp().

◆ isOrdered()

bool llvm::Dependence::isOrdered ( ) const

inline

isOrdered - Returns true if dependence is Output, Flow, or Anti

Definition at line 136 of file DependenceAnalysis.h.

References isAnti(), isFlow(), and isOutput().

◆ isOutput()

bool Dependence::isOutput ( ) const

isOutput - Returns true if this is an output dependence.

Definition at line 494 of file DependenceAnalysis.cpp.

References Dst, and Src.

Referenced by dump(), and isOrdered().

◆ isPeelFirst()

virtual bool llvm::Dependence::isPeelFirst	(	unsigned	Level,
		bool	SameSD = false ) const

inlinevirtual

isPeelFirst - Returns true if peeling the first iteration from this regular or SameSD loop level will break this dependence.

Reimplemented in llvm::FullDependence.

Definition at line 189 of file DependenceAnalysis.h.

Referenced by dumpImp().

◆ isPeelLast()

virtual bool llvm::Dependence::isPeelLast	(	unsigned	Level,
		bool	SameSD = false ) const

inlinevirtual

isPeelLast - Returns true if peeling the last iteration from this regular or SameSD loop level will break this dependence.

Reimplemented in llvm::FullDependence.

Definition at line 195 of file DependenceAnalysis.h.

Referenced by dumpImp().

◆ isScalar()

bool Dependence::isScalar	(	unsigned	Level,
		bool	SameSD = false ) const

virtual

isScalar - Returns true if a particular regular or SameSD level is scalar; that is, if no subscript in the source or destination mention the induction variable associated with the loop at this level.

Reimplemented in llvm::FullDependence.

Definition at line 512 of file DependenceAnalysis.cpp.

Referenced by dumpImp().

◆ isSplitable()

virtual bool llvm::Dependence::isSplitable	(	unsigned	Level,
		bool	SameSD = false ) const

inlinevirtual

isSplitable - Returns true if splitting the loop will break the dependence.

Reimplemented in llvm::FullDependence.

Definition at line 201 of file DependenceAnalysis.h.

Referenced by dumpImp(), and llvm::DependenceInfo::getSplitIteration().

◆ isUnordered()

bool llvm::Dependence::isUnordered ( ) const

inline

isUnordered - Returns true if dependence is Input

Definition at line 139 of file DependenceAnalysis.h.

References isInput().

◆ normalize()

virtual bool llvm::Dependence::normalize ( ScalarEvolution * SE )

inlinevirtual

If the direction vector is negative, normalize the direction vector to make it non-negative.

Normalization is done by reversing Src and Dst, plus reversing the dependence directions and distances in the vector.

Reimplemented in llvm::FullDependence.

Definition at line 185 of file DependenceAnalysis.h.

◆ operator=()

Dependence & llvm::Dependence::operator= ( Dependence && )

protecteddefault

References Dependence().

◆ setNextPredecessor()

void llvm::Dependence::setNextPredecessor ( const Dependence * pred )

inline

setNextPredecessor - Sets the value of the NextPredecessor field.

Definition at line 223 of file DependenceAnalysis.h.

References Dependence().

◆ setNextSuccessor()

void llvm::Dependence::setNextSuccessor ( const Dependence * succ )

inline

setNextSuccessor - Sets the value of the NextSuccessor field.

Definition at line 226 of file DependenceAnalysis.h.

References Dependence().

◆ DependenceInfo

friend class DependenceInfo

friend

Definition at line 245 of file DependenceAnalysis.h.

References DependenceInfo.

Referenced by DependenceInfo.

Member Data Documentation

◆ Dst

Instruction * llvm::Dependence::Dst

protected

Definition at line 240 of file DependenceAnalysis.h.

Referenced by Dependence(), getDst(), isAnti(), isFlow(), isInput(), isOutput(), and llvm::FullDependence::normalize().

◆ Src

Instruction* llvm::Dependence::Src

protected

Definition at line 240 of file DependenceAnalysis.h.

Referenced by Dependence(), getSrc(), isAnti(), isFlow(), isInput(), isOutput(), and llvm::FullDependence::normalize().

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

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

Classes

Public Member Functions

Protected Member Functions

Protected Attributes

Friends

Detailed Description

Constructor & Destructor Documentation

◆ Dependence() [1/2]

◆ Dependence() [2/2]

◆ ~Dependence()

Member Function Documentation

◆ dump()

◆ dumpImp()

◆ getDirection()

◆ getDistance()

◆ getDst()

◆ getDVEntry()

◆ getLevels()

◆ getNextPredecessor()

◆ getNextSuccessor()

◆ getRuntimeAssumptions()

◆ getSameSDLevels()

◆ getSrc()

◆ inSameSDLoops()

◆ isAnti()

◆ isConfused()

◆ isConsistent()

◆ isDirectionNegative()

◆ isFlow()

◆ isInput()

◆ isLoopIndependent()

◆ isOrdered()

◆ isOutput()

◆ isPeelFirst()

◆ isPeelLast()

◆ isScalar()

◆ isSplitable()

◆ isUnordered()

◆ normalize()

◆ operator=()

◆ setNextPredecessor()

◆ setNextSuccessor()

Friends And Related Symbol Documentation

◆ DependenceInfo

Member Data Documentation

◆ Dst

◆ Src