com.ibm.wala.fixpoint
Class UnaryOperator<T extends IVariable>

java.lang.Object
  com.ibm.wala.fixpoint.AbstractOperator<T>
      com.ibm.wala.fixpoint.UnaryOperator<T>

All Implemented Interfaces:

FixedPointConstants

Direct Known Subclasses:

BitVectorFilter, BitVectorIdentity, BitVectorKillAll, BitVectorKillGen, BitVectorMinusVector, BitVectorOr, BitVectorUnionConstant, BitVectorUnionVector, BooleanIdentity, PropagationCallGraphBuilder.FilterOperator, PropagationCallGraphBuilder.InstanceArrayStoreOperator, PropagationCallGraphBuilder.InstancePutFieldOperator, TrueOperator, UnaryBitVectorUnion, UnaryOr, UnarySideEffect

public abstract class UnaryOperator<T extends IVariable>
extends AbstractOperator<T>
implements FixedPointConstants

An operator of the form lhs = op (rhs)

Field Summary

Fields inherited from interface com.ibm.wala.fixpoint.FixedPointConstants

CHANGED, CHANGED_AND_FIXED, CHANGED_MASK, FIXED_MASK, NOT_CHANGED, NOT_CHANGED_AND_FIXED, SIDE_EFFECT_MASK

Constructor Summary

UnaryOperator()

Method Summary

abstract byte	evaluate(T lhs, T rhs) Evaluate this equation, setting a new value for the left-hand side.
byte	evaluate(T lhs, T[] rhs) Evaluate this equation, setting a new value for the left-hand side.
boolean	isIdentity()
UnaryStatement<T>	makeEquation(T lhs, T rhs) Create an equation which uses this operator Override in subclasses for efficiency.

Methods inherited from class com.ibm.wala.fixpoint.AbstractOperator

equals, hashCode, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

UnaryOperator

public UnaryOperator()

Method Detail

evaluate

public abstract byte evaluate(T lhs,
                              T rhs)

Evaluate this equation, setting a new value for the left-hand side.

Returns:

true if the lhs value changes. false otherwise.

makeEquation

public UnaryStatement<T> makeEquation(T lhs,
                                      T rhs)

Create an equation which uses this operator Override in subclasses for efficiency.

isIdentity

public boolean isIdentity()

evaluate

public byte evaluate(T lhs,
                     T[] rhs)
              throws UnimplementedError

Description copied from class: AbstractOperator

Evaluate this equation, setting a new value for the left-hand side. Note that the RHS is an IVariable[] and not a T[] because the framework may be need to allocate an array for the rhs, and we cannot do new T[] in Java.

Specified by:

evaluate in class AbstractOperator<T extends IVariable>

Returns:

a code that indicates: 1) has the lhs value changed? 2) has this equation reached a fixed-point, in that we never have to evaluate the equation again, even if rhs operands change?

Throws:

UnimplementedError