org.jikesrvm.compilers.opt.ssa
Class IndexPropagationSystem.UpdateDefArrayOperator

java.lang.Object
  org.jikesrvm.compilers.opt.dfsolver.DF_Operator
      org.jikesrvm.compilers.opt.ssa.IndexPropagationSystem.UpdateDefArrayOperator

Enclosing class:

IndexPropagationSystem

 class IndexPropagationSystem.UpdateDefArrayOperator
extends DF_Operator

Represents an UPDATE_DEF function over two ArrayCells. Given two value numbers v1, v2, this function updates a heap variable lattice cell to indicate that element for array v1 at address v2 is available, but kills any available indices that are not DD from

v

private final ValueNumberPair v

The value number pair used in the dataflow equation.

IndexPropagationSystem.UpdateDefArrayOperator

IndexPropagationSystem.UpdateDefArrayOperator(int v1,
                                              int v2)

Create an operator with a given value number pair

Parameters:

v1 - first value number in the pari

v2 - first value number in the pari

toString

public String toString()

Overrides:

toString in class Object

Returns:

"UPDATE-DEF"

evaluate

public boolean evaluate(DF_LatticeCell[] operands)

Evaluate the dataflow equation with this operator.

Specified by:

evaluate in class DF_Operator

Parameters:

operands - operands in the dataflow equation

Returns:

true iff the lhs changes from this evaluation