scale.score.expr
Class TranscendentalExpr

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

All Implemented Interfaces:

AnnotationInterface, DisplayNode

public class TranscendentalExpr
extends UnaryExpr

This class represents the monadic intrinsic functions.

$Id: TranscendentalExpr.java,v 1.23 2007-10-04 19:58:33 burrill Exp $

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

If would have been better to name this class the BuiltInOperation class. It represents those complex operations which it may be possible to implement on the target architecture with a simple sequence of instructions. An example is the square root function which some architectures provide as a single instruction.

See Also:

TranscendentalOp

Field Summary

Fields inherited from class scale.score.expr.Expr

fpReorder, SE_DOMAIN, SE_NONE, SE_OVERFLOW, SE_STATE

Constructor Summary

TranscendentalExpr(Type t, Expr e1, TransFtn ftn)

Method Summary

Expr	copy() Perform a deep copy of the expression tree.
boolean	equivalent(Expr exp) Return true if the expressions are equivalent.
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.
Literal	getConstantValue() Return the constant value of the expression.
Literal	getConstantValue(HashMap<Expr,Literal> cvMap) Return the constant value of the expression.
java.lang.String	getDisplayLabel() Return a String suitable for labeling this node in a graphical display.
TransFtn	getFtn() Return a value indicating the transcendental function represented.
boolean	isLoopInvariant(LoopHeaderChord loop) Return true if this expression is loop invariant.
boolean	mayGenerateCall() Return true if this expression may result in the generation of a call to a subroutine.
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.
void	visit(Predicate p) Process a node by calling its associated routine.

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, canonical, changeInDataEdge, conditionalCopy, conditionalUnlinkExpression, deleteOutDataEdge, executionOrder, executionOrdinal, findLinearCoefficient, findSubscriptExpr, getAffineExpr, getAffineRepresentation, getCall, getCoreType, getCriticalChord, getDefExpr, getDisplayColorHint, getDisplayShapeHint, getDualExpr, getInDataEdge, getInDataEdgeArray, getLoopHeader, getLow, getLValue, getOutDataEdge, getPointedToCore, getReference, getReuseLevel, getRValue, getType, getUseDef, hasTrueFalseResult, isCast, isDefined, isDefined, isLiteralExpr, isMatchExpr, isMemoryDef, isMemRefExpr, isScalar, isSimpleExpr, 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

TranscendentalExpr

public TranscendentalExpr(Type t,
                          Expr e1,
                          TransFtn ftn)

Method Detail

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 UnaryExpr

Returns:

true if the expressions are equivalent

getFtn

public TransFtn getFtn()

Return a value indicating the transcendental function represented.

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

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

mayGenerateCall

public boolean mayGenerateCall()

Return true if this expression may result in the generation of a call to a subroutine.

Overrides:

mayGenerateCall in class Expr

isLoopInvariant

public boolean isLoopInvariant(LoopHeaderChord loop)

Return true if this expression is loop invariant.

Overrides:

isLoopInvariant in class Expr

Parameters:

loop - is the loop

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

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

getConstantValue

public Literal getConstantValue(HashMap<Expr,Literal> cvMap)

Return the constant value of the expression. Follow use-def links.

Overrides:

getConstantValue in class Expr

See Also:

Lattice

getConstantValue

public Literal getConstantValue()

Return the constant value of the expression. Do not follow use-def links.

Overrides:

getConstantValue in class Expr

See Also:

Lattice

executionCostEstimate

public int executionCostEstimate()

Return a relative cost estimate for executing the expression.

Overrides:

executionCostEstimate in class UnaryExpr