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

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

Enclosing class:

IndexPropagationSystem

static class IndexPropagationSystem.UpdateUseArrayOperator
extends DF_Operator

Represents an UPDATE_USE function over two ArrayCells.

Given two value numbers v1, v2, this function updates a heap variable lattice cell to indicate that element at array v1 index v2 is available, and doesn't kill any available indices

v

private final ValueNumberPair v

The value number pair used in the dataflow equation.

IndexPropagationSystem.UpdateUseArrayOperator

IndexPropagationSystem.UpdateUseArrayOperator(int v1,
                                              int v2)

Create an operator with a given value number pair

Parameters:

v1 - first value number in the pair

v2 - second value number in the pair

toString

public String toString()

Overrides:

toString in class Object

Returns:

"UPDATE-USE"

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