scale.score.expr
Class LoadExpr

java.lang.Object
  scale.common.Root
      scale.score.Note
          scale.score.expr.Expr
              scale.score.expr.LoadExpr

All Implemented Interfaces:

AnnotationInterface, DisplayNode

Direct Known Subclasses:

LoadDeclAddressExpr, LoadDeclValueExpr

public abstract class LoadExpr
extends Expr

This class is the base class for expressions that represent references to memory.

$Id: LoadExpr.java,v 1.90 2007-10-17 13:40:00 burrill Exp $

Copyright 2008 by the Scale Compiler Group,
Department of Computer Science
University of Massachusetts,
Amherst MA. 01003, USA
All Rights Reserved.

This class represents use-def chains.

Field Summary

Fields inherited from class scale.score.expr.Expr

fpReorder, SE_DOMAIN, SE_NONE, SE_OVERFLOW, SE_STATE

Constructor Summary

protected	LoadExpr()
	LoadExpr(Type t, Declaration decl)

Method Summary

void	addMayUse(MayUse mayUse) Add may use information to the load expression.
long	canonical() Return a unique value representing this particular expression.
boolean	containsDeclaration(Declaration decl) Return true if this expression contains a reference to the variable.
abstract Expr	copyNoUD() Make a copy of this load expression without the use - def information.
boolean	dependsOnDeclaration(Declaration decl) Return true if this expression's value depends on the variable.
boolean	equivalent(Expr exp) Return true if the expressions are equivalent.
SubscriptExpr	findSubscriptExpr() Return the SubscriptExpr that this load uses or null if none is found.
AliasAnnote	getAliasAnnote() Get the alias annotation associated with a Scribble operator.
Declaration	getDecl() Return the Clef declaration of the variable being loaded.
void	getDeclList(java.util.AbstractCollection<Declaration> varList) Add all declarations referenced in this expression to the Vector.
void	getExprList(Vector<Expr> expList) Add all Expr instances in this expression to the Vector.
void	getLoadExprList(Vector<LoadExpr> expList) Add all LoadExpr instances in this expression to the Vector.
MayUse	getMayUse() Return the may use information assocaited with the load.
java.lang.String	getName() Return the name of the declaration being loaded.
Expr	getObject() Given a load expression, return the object expression for the load.
Expr[]	getOperandArray() Return an array of the operands to the expression.
Expr	getReference() Return the value associated with the load expression.
int	getReuseLevel()
Declaration	getSubsetDecl() Return the original declaration of the value loaded.
ExprChord	getUseDef() Return the ExprChord that defines the value load by this load expression.
boolean	isMemoryDef() Return true if the node reference is a definition.
boolean	isMemRefExpr() Return true if the expression loads a value from memory.
void	loopClean() Clean up any loop related information.
int	numOperands() Return the number of operands to this expression.
void	pushOperands(Stack<Expr> wl) Push all of the operands of this expression on the Stack.
void	recordRefs(Chord stmt, References refs) Record any variable references in this expression in the table of references.
boolean	referencesVariableInCommon() Return true if the variable referenced is in Fortran COMMON.
void	removeRefs(Chord stmt, References refs) Remove any variable references in this expression from the table of references.
void	removeUseDef() Remove any use - def links, may - use links, etc.
boolean	replaceDecl(Declaration oldDecl, Declaration newDecl) Replace all occurrances of a Declaration with another Declaration.
void	setCrossloopReuse(int level)
void	setDecl(Declaration decl) Change the declaration associated with the load operation.
void	setSpatialReuse(int level)
void	setStep(int step)
void	setTemporalReuse(int level)
void	setUseDef(ExprChord expr) Define a link from this load of a value to the scale.score.chords.ExprChord that defines the value.
static boolean	setUseMayUse(boolean flg) Specify whether the equivalent() method should use the may-use information.
static boolean	setUseOriginal(boolean flg) Specify whether the equivalent() method should use the non-SSA original VariableDecl.
int	sideEffects() Return an indication of the side effects execution of this expression may cause.
void	unlinkExpression() If the node is no longer needed, sever its use-def link, etc.
void	validate() Check this node for validity.
boolean	validLValue() Return true if this expression is valid on the left side of an assignment.

Methods inherited from class scale.score.expr.Expr

addCast, addCast, changeInDataEdge, conditionalCopy, conditionalUnlinkExpression, copy, deleteOutDataEdge, executionOrder, executionOrdinal, findCriticalChord, findLinearCoefficient, getAffineExpr, getAffineRepresentation, getCall, getConstantValue, getConstantValue, getCoreType, getCriticalChord, getDefExpr, getDisplayColorHint, getDisplayLabel, getDisplayShapeHint, getDualExpr, getInDataEdge, getInDataEdgeArray, getLoopHeader, getLow, getLValue, getOperand, getOutDataEdge, getPointedToCore, getRValue, getType, hasTrueFalseResult, isCast, isDefined, isDefined, isLiteralExpr, isLoopInvariant, isMatchExpr, isScalar, isSimpleExpr, mayGenerateCall, numInDataEdges, optimizationCandidate, reduce, removeDualExprs, setOperand, setOutDataEdge, setType, toStringSpecial

Methods inherited from class scale.score.Note

executionCostEstimate, getChord, getEssentialUse, setAnnotationLevel, setReportLevel, toString, visit

Methods inherited from class scale.common.Root

addAnnotation, allAnnotations, allMatchingAnnotations, getAnnotation, getDisplayName, getDisplayString, getNodeCount, getNodeID, hasAnnotation, hasEqualAnnotation, hashCode, removeAnnotation, removeAnnotations, toStringAnnotations, toStringClass, trace, trace, trace

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

LoadExpr

public LoadExpr(Type t,
                Declaration decl)

LoadExpr

protected LoadExpr()

Method Detail

getSubsetDecl

public Declaration getSubsetDecl()

Return the original declaration of the value loaded. This is the variable before SSA renumbering is used to determine whether two virtual vars are in the same subset or if one is a superset. Hence the name.

equivalent

public boolean equivalent(Expr exp)

Return true if the expressions are equivalent. This method should be called by the equivalent() method of the derived classes.

Overrides:

equivalent in class Expr

Returns:

true if the expressions are equivalent

See Also:

setUseOriginal(boolean)

setUseOriginal

public static boolean setUseOriginal(boolean flg)

Specify whether the equivalent() method should use the non-SSA original VariableDecl.

Returns:

the previous setting

See Also:

equivalent(scale.score.expr.Expr), PRE

setUseMayUse

public static boolean setUseMayUse(boolean flg)

Specify whether the equivalent() method should use the may-use information.

Returns:

the previous setting

See Also:

equivalent(scale.score.expr.Expr), ValNum

copyNoUD

public abstract Expr copyNoUD()

Make a copy of this load expression without the use - def information.

setUseDef

public final void setUseDef(ExprChord expr)

Define a link from this load of a value to the scale.score.chords.ExprChord that defines the value.

Overrides:

setUseDef in class Expr

Parameters:

expr - the new use-def link

getUseDef

public final ExprChord getUseDef()

Return the ExprChord that defines the value load by this load expression.

Overrides:

getUseDef in class Expr

addMayUse

public void addMayUse(MayUse mayUse)

Add may use information to the load expression.

Parameters:

mayUse - the expresion representing the may use

getMayUse

public final MayUse getMayUse()

Return the may use information assocaited with the load.

removeUseDef

public void removeUseDef()

Remove any use - def links, may - use links, etc.

Specified by:

removeUseDef in class Expr

getDecl

public final Declaration getDecl()

Return the Clef declaration of the variable being loaded.

setDecl

public final void setDecl(Declaration decl)

Change the declaration associated with the load operation.

Parameters:

decl - is the new declataion

getName

public java.lang.String getName()

Return the name of the declaration being loaded.

getOperandArray

public final Expr[] getOperandArray()

Return an array of the operands to the expression.

Specified by:

getOperandArray in class Expr

numOperands

public final int numOperands()

Return the number of operands to this expression.

Specified by:

numOperands in class Expr

getReference

public Expr getReference()

Return the value associated with the load expression. The value is the load itself.

Overrides:

getReference in class Expr

Returns:

the load expression.

getObject

public Expr getObject()

Given a load expression, return the object expression for the load. This is the converse of getReference. If the expression is the structure or array name which is part of a field reference or array subscript then return the expression representing the field or the subscript. For a scalar load, the method returns the load.

Returns:

the object representing the load.

canonical

public long canonical()

Return a unique value representing this particular expression.

Overrides:

canonical in class Expr

loopClean

public void loopClean()

Clean up any loop related information.

Overrides:

loopClean in class Expr

unlinkExpression

public void unlinkExpression()

If the node is no longer needed, sever its use-def link, etc.

Overrides:

unlinkExpression in class Expr

isMemoryDef

public boolean isMemoryDef()

Return true if the node reference is a definition. That is, does this node represents a write to a memory location.

Overrides:

isMemoryDef in class Expr

findSubscriptExpr

public SubscriptExpr findSubscriptExpr()

Return the SubscriptExpr that this load uses or null if none is found. This method uses the use-def link to find an existing SubscriptExpr

Overrides:

findSubscriptExpr in class Expr

setTemporalReuse

public void setTemporalReuse(int level)

Overrides:

setTemporalReuse in class Expr

setCrossloopReuse

public void setCrossloopReuse(int level)

Overrides:

setCrossloopReuse in class Expr

setSpatialReuse

public void setSpatialReuse(int level)

Overrides:

setSpatialReuse in class Expr

setStep

public void setStep(int step)

Overrides:

setStep in class Expr

getReuseLevel

public int getReuseLevel()

Overrides:

getReuseLevel in class Expr

isMemRefExpr

public boolean isMemRefExpr()

Return true if the expression loads a value from memory.

Overrides:

isMemRefExpr in class Expr

referencesVariableInCommon

public final boolean referencesVariableInCommon()

Return true if the variable referenced is in Fortran COMMON.

validLValue

public boolean validLValue()

Return true if this expression is valid on the left side of an assignment.

Overrides:

validLValue in class Expr

containsDeclaration

public final boolean containsDeclaration(Declaration decl)

Return true if this expression contains a reference to the variable.

Overrides:

containsDeclaration in class Expr

See Also:

setUseOriginal(boolean)

dependsOnDeclaration

public final boolean dependsOnDeclaration(Declaration decl)

Return true if this expression's value depends on the variable. The use-def links are followed.

Overrides:

dependsOnDeclaration in class Expr

See Also:

setUseOriginal(boolean)

getAliasAnnote

public AliasAnnote getAliasAnnote()

Get the alias annotation associated with a Scribble operator. Most Scribble operators do not have alias variables so this routine may return null. Typically, the alias variable information is attached to the declaration node associated with the load operations. However, we sometimes need to create alias variables to hold alias information that is not directly assigned to a user variable (e.g., **x).

Overrides:

getAliasAnnote in class Expr

Returns:

the alias annotation associated with the expression

getDeclList

public void getDeclList(java.util.AbstractCollection<Declaration> varList)

Add all declarations referenced in this expression to the Vector.

Specified by:

getDeclList in class Expr

getLoadExprList

public void getLoadExprList(Vector<LoadExpr> expList)

Add all LoadExpr instances in this expression to the Vector.

Specified by:

getLoadExprList in class Expr

getExprList

public void getExprList(Vector<Expr> expList)

Add all Expr instances in this expression to the Vector.

Specified by:

getExprList in class Expr

pushOperands

public void pushOperands(Stack<Expr> wl)

Push all of the operands of this expression on the Stack.

Specified by:

pushOperands in class Expr

replaceDecl

public boolean replaceDecl(Declaration oldDecl,
                           Declaration newDecl)

Replace all occurrances of a Declaration with another Declaration. Return true if a replace occurred.

Specified by:

replaceDecl in class Expr

Returns:

true if a replace occurred.

validate

public void validate()

Check this node for validity. This method throws an exception if the node is not linked properly.

Overrides:

validate in class Expr

recordRefs

public void recordRefs(Chord stmt,
                       References refs)

Record any variable references in this expression in the table of references.

Specified by:

recordRefs in class Expr

removeRefs

public void removeRefs(Chord stmt,
                       References refs)

Remove any variable references in this expression from the table of references.

Specified by:

removeRefs in class Expr

sideEffects

public int sideEffects()

Return an indication of the side effects execution of this expression may cause.

Specified by:

sideEffects in class Expr

See Also:

Expr.SE_NONE