scale.backend
Class StackDisplacement

java.lang.Object
  scale.backend.Displacement
      scale.backend.StackDisplacement

public class StackDisplacement
extends Displacement

This class represents a displacement field in an instruction when the displacement refers to an offset on the stack.

$Id: StackDisplacement.java,v 1.18 2007-09-20 18:57:40 burrill Exp $

Copyright 2007 by the Scale Compiler Group,
Department of Computer Science
University of Massachusetts,
Amherst MA. 01003, USA
All Rights Reserved.

A separate class is used for this so that instanceof may be used to distinguish between a normal displacement and a stack displacement. Also, stack displacements must often be changed after the code for a routine is generated to reflect additional stack entries for spills, etc.

Constructor Summary

StackDisplacement(long offset)

Method Summary

void	adjust(int adjustment) Adjust the displacement by the specified value.
java.lang.String	assembler(Assembler asm) Generate a String representation that can be used by the assembly code generater.
boolean	equivalent(java.lang.Object o) Return true if the displacements are equivalent.
long	getDisplacement() Return the displacement.
boolean	isNumeric() Return true if the displacement can be represented as a number.
boolean	isStack() Return true if the displacement is from the stack pointer.
boolean	isZero() Return true if the displacement is zero.
java.lang.String	toString()
Displacement	unique() Returns this.

Methods inherited from class scale.backend.Displacement

created, getBase, isSymbol, offset

Methods inherited from class java.lang.Object

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

Constructor Detail

StackDisplacement

public StackDisplacement(long offset)

Method Detail

isNumeric

public boolean isNumeric()

Return true if the displacement can be represented as a number.

Overrides:

isNumeric in class Displacement

getDisplacement

public long getDisplacement()

Return the displacement.

Overrides:

getDisplacement in class Displacement

isStack

public boolean isStack()

Return true if the displacement is from the stack pointer.

Overrides:

isStack in class Displacement

isZero

public boolean isZero()

Return true if the displacement is zero.

Overrides:

isZero in class Displacement

adjust

public void adjust(int adjustment)

Adjust the displacement by the specified value.

Overrides:

adjust in class Displacement

unique

public Displacement unique()

Returns this.

Specified by:

unique in class Displacement

See Also:

SymbolDisplacement

assembler

public java.lang.String assembler(Assembler asm)

Generate a String representation that can be used by the assembly code generater.

Specified by:

assembler in class Displacement

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

equivalent

public boolean equivalent(java.lang.Object o)

Return true if the displacements are equivalent.

Overrides:

equivalent in class Displacement