scale.score.expr
Class AllocateExpr

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

All Implemented Interfaces:

AnnotationInterface, DisplayNode

public class AllocateExpr
extends UnaryExpr

This class represents the Allocate function.

$Id: AllocateExpr.java,v 1.18 2007-10-04 19:58:28 burrill Exp $

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

The operand specifies the amount of space to allocate. The value of the operation is the address of the allocated area.

We use instances of this class instead of generating functions calls because it may be possible to do allocations by simple pointer operations in registers. By using this class, Scribble2C can generate a function call. When going direct to machine code, an instance of this class can be converted directly into machine instructions.

Field Summary

Fields inherited from class scale.score.expr.Expr

fpReorder, SE_DOMAIN, SE_NONE, SE_OVERFLOW, SE_STATE

Constructor Summary

AllocateExpr(Expr arg)
The expression type is a (void*).

AllocateExpr(Type type, Expr arg, boolean initialize)

Method Summary

Expr	copy() Perform a deep copy of the expression tree.
java.lang.String	getDisplayLabel() Return a String suitable for labeling this node in a graphical display.
boolean	getInitializationMode() Return true if the memory for the allocated object should be cleared to zeros.
int	sideEffects() Return an indication of the side effects execution of this expression may cause.
void	visit(Predicate p) Process a node by calling its associated routine.

Methods inherited from class scale.score.expr.UnaryExpr

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

Methods inherited from class scale.score.expr.Expr

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

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

AllocateExpr

public AllocateExpr(Type type,
                    Expr arg,
                    boolean initialize)

Parameters:

type - is the expression type

arg - is the left operand

initialize - is true if the memory for the allocated object should be cleared to zeros

AllocateExpr

public AllocateExpr(Expr arg)

The expression type is a (void*).

Parameters:

arg - is the left operand

Method Detail

copy

public Expr copy()

Description copied from class: Expr

Perform a deep copy of the expression tree. By deep copy, we mean that copies are made of the expression tree.

Specified by:

copy in class Expr

Returns:

a copy of this expression

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

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

getDisplayLabel

public java.lang.String getDisplayLabel()

Description copied from class: Expr

Return a String suitable for labeling this node in a graphical display. This method should be over-ridden as it simplay returns the class name.

Specified by:

getDisplayLabel in interface DisplayNode

Overrides:

getDisplayLabel in class Expr

getInitializationMode

public boolean getInitializationMode()

Return true if the memory for the allocated object should be cleared to zeros.