coins.ssa
Class RedundantPhiElimination

java.lang.Object
  coins.ssa.RedundantPhiElimination

All Implemented Interfaces:

LocalTransformer, Transformer

class RedundantPhiElimination

extends java.lang.Object

implements LocalTransformer

Eliminate the redundant PHI instructions.

The redundant PHI instruction is defined as follows:
1) x=phi(x,x,x) (remove only)
2) x=phi(y,y,y) (regard as `x=y' and do copy propagation)
3) x=phi(y,y,x) (regard as `x=y' and do copy propagation)

Field Summary

static int

THR The threshold of the debug print

Constructor Summary

RedundantPhiElimination(SsaEnvironment e)
Constructor

Method Summary

boolean	doIt(Data data, ImList args) Transform the DATA component.
boolean	doIt(Function function, ImList args) Eliminate the redundant PHI instructions.
java.lang.String	name() Return the name of the transforming engine.
java.lang.String	subject() Return brief description of the tranformation.

Methods inherited from class java.lang.Object

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

Field Detail

THR

public static final int THR

The threshold of the debug print

See Also:

Constant Field Values

Constructor Detail

RedundantPhiElimination

public RedundantPhiElimination(SsaEnvironment e)

Constructor

Parameters:

e - The environment of the SSA module

Method Detail

doIt

public boolean doIt(Data data,
                    ImList args)

Description copied from interface: LocalTransformer

Transform the DATA component.

Specified by:

doIt in interface LocalTransformer

Parameters:

data - DATA to be transformed.

args - list of optional arguments.

Returns:

true if transformation suceeded.

name

public java.lang.String name()

Description copied from interface: Transformer

Return the name of the transforming engine. Used for trace tag name.

Specified by:

name in interface Transformer

Returns:

the name of the transforming engine.

subject

public java.lang.String subject()

Description copied from interface: Transformer

Return brief description of the tranformation.

Specified by:

subject in interface Transformer

Returns:

brief description of the tranformation.

doIt

public boolean doIt(Function function,
                    ImList args)

Eliminate the redundant PHI instructions.

Specified by:

doIt in interface LocalTransformer

Parameters:

function - The current funciton

args - The list of options

Returns:

true if transformation suceeded.