scale.score.expr
Class LoadFieldValueExpr

java.lang.Object
  scale.common.Root
      scale.score.Note
          scale.score.expr.Expr
              scale.score.expr.UnaryExpr
                  scale.score.expr.FieldExpr
                      scale.score.expr.LoadFieldValueExpr

All Implemented Interfaces:

AnnotationInterface, DisplayNode

public class LoadFieldValueExpr
extends FieldExpr

This class represents the value of a field of a structure.

$Id: LoadFieldValueExpr.java,v 1.21 2007-10-04 19:58:31 burrill Exp $

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

Field Summary

Fields inherited from class scale.score.expr.Expr

fpReorder, SE_DOMAIN, SE_NONE, SE_OVERFLOW, SE_STATE

Constructor Summary

LoadFieldValueExpr(Expr structure, FieldDecl field)
This method builds an expression node with this operation as the operator.

Method Summary

Expr	copy() Make a copy of this load expression.
Expr	copyNoUD() Make a copy of this load expression without the use - def information.
int	executionCostEstimate() Return a relative cost estimate for executing the expression.
protected Chord	findCriticalChord(HashMap<Expr,Chord> lMap, Chord independent) Return the Chord with the highest label value from the set of Chords that must be executed before this expression.
boolean	optimizationCandidate() Return true if the expression can be moved without problems.
int	sideEffects() Return an indication of the side effects execution of this expression may cause.
boolean	validLValue() Return true if this expression is valid on the left side of an assignment.
void	visit(Predicate p) Process a node by calling its associated routine.

Methods inherited from class scale.score.expr.FieldExpr

canonical, equivalent, getDisplayLabel, getField, getReference, getStructure, isDefined, isLoopInvariant, isMemRefExpr

Methods inherited from class scale.score.expr.UnaryExpr

containsDeclaration, dependsOnDeclaration, getAliasAnnote, getArg, getDeclList, getExprList, getLoadExprList, getOperand, getOperandArray, loopClean, numOperands, pushOperands, recordRefs, removeRefs, removeUseDef, replaceDecl, setArg, setOperand, unlinkExpression, validate

Methods inherited from class scale.score.expr.Expr

addCast, addCast, changeInDataEdge, conditionalCopy, conditionalUnlinkExpression, deleteOutDataEdge, executionOrder, executionOrdinal, findLinearCoefficient, findSubscriptExpr, getAffineExpr, getAffineRepresentation, getCall, getConstantValue, getConstantValue, getCoreType, getCriticalChord, getDefExpr, getDisplayColorHint, getDisplayShapeHint, getDualExpr, getInDataEdge, getInDataEdgeArray, getLoopHeader, getLow, getLValue, getOutDataEdge, getPointedToCore, getReuseLevel, getRValue, getType, getUseDef, hasTrueFalseResult, isCast, isDefined, isLiteralExpr, isMatchExpr, isMemoryDef, isScalar, isSimpleExpr, mayGenerateCall, numInDataEdges, reduce, removeDualExprs, setCrossloopReuse, setOutDataEdge, setSpatialReuse, setStep, setTemporalReuse, setType, setUseDef, toStringSpecial

Methods inherited from class scale.score.Note

getChord, getEssentialUse, setAnnotationLevel, setReportLevel, toString

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

LoadFieldValueExpr

public LoadFieldValueExpr(Expr structure,
                          FieldDecl field)

This method builds an expression node with this operation as the operator.

Parameters:

structure - is the address of the structure accessed

field - specifies the field of the structure

Method Detail

copy

public Expr copy()

Make a copy of this load expression. The use - def information is copied too.

Specified by:

copy in class Expr

Returns:

a copy of this expression

copyNoUD

public Expr copyNoUD()

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

findCriticalChord

protected Chord findCriticalChord(HashMap<Expr,Chord> lMap,
                                  Chord independent)

Return the Chord with the highest label value from the set of Chords that must be executed before this expression.

Overrides:

findCriticalChord in class Expr

Parameters:

lMap - is used to memoize the expression to critical Chord information

independent - is returned if the expression is not dependent on anything

visit

public void visit(Predicate p)

Description copied from class: Note

Process a node by calling its associated routine. See the "visitor" design pattern in Design Patterns: Elements of Reusable Object-Oriented Software by E. Gamma, et al, Addison Wesley, ISBN 0-201-63361-2.

Each class has a visit(Predicate p) method. For example, in class ABC:

   public void visit(Predicate p)
   {
     p.visitABC(this);
   }
 

and the class that implements Predicate has a method

   public void visitABC(Note n)
   {
     ABC a = (ABC) n;
     ...
   }
 

Thus, the class that implements Predicate can call

   n.visit(this);
 

where n is a Note sub-class without determining which specific sub-class n is. The visit pattern basically avoids implementing a large switch statement or defining different methods in each class for some purpose.

Specified by:

visit in class Note

See Also:

Predicate

validLValue

public boolean validLValue()

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

Overrides:

validLValue in class Expr

executionCostEstimate

public int executionCostEstimate()

Return a relative cost estimate for executing the expression.

Overrides:

executionCostEstimate in class UnaryExpr

sideEffects

public int sideEffects()

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

Overrides:

sideEffects in class UnaryExpr

See Also:

Expr.SE_NONE

optimizationCandidate

public boolean optimizationCandidate()

Return true if the expression can be moved without problems. Expressions that reference global variables, non-atomic variables, etc are not optimization candidates.

Overrides:

optimizationCandidate in class UnaryExpr