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

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

Enclosing class:

IndexPropagationSystem

static class IndexPropagationSystem.UpdateUseObjectOperator
extends DF_Operator

Represents an UPDATE_USE function over two ObjectCells.

Given a value number v, this function updates a heap variable lattice cell to indicate that element at address v is available, and doesn't kill any available indices

valueNumber

private final int valueNumber

The value number used in the dataflow equation.

IndexPropagationSystem.UpdateUseObjectOperator

IndexPropagationSystem.UpdateUseObjectOperator(int valueNumber)

Create an operator with a given value number

Parameters:

valueNumber -

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