org.jikesrvm.compilers.opt.escape

Class ShortArrayReplacer

java.lang.Object

org.jikesrvm.compilers.opt.escape.ShortArrayReplacer

All Implemented Interfaces:

AggregateReplacer

final class ShortArrayReplacer
extends Object
implements AggregateReplacer

Class that performs scalar replacement of short arrays

Field Summary

Fields

Modifier and Type	Field and Description
private IR	ir the governing IR
private Register	reg the register holding the array reference
private int	size number of elements in the array
private RVMArray	vmArray type of the array

Constructor Summary

Constructors

Modifier	Constructor and Description
private	ShortArrayReplacer(Register r, RVMArray a, int s, IR i)

Method Summary

Modifier and Type	Method and Description
private static boolean	containsUnsupportedUse(IR ir, Register reg, int size, RVMArray vmArray, Set<Register> visited) Some cases we don't handle yet.
static ShortArrayReplacer	getReplacer(Instruction inst, IR ir) Returns an object representing this transformation for a given allocation site.
private void	scalarReplace(RegisterOperand use, RegisterOperand[] scalars, Set<Register> visited) Replace a given use of an array with its scalar equivalent.
void	transform() Perform the transformation
private void	transform2(Register reg, Instruction defI, RegisterOperand[] scalars)

Methods inherited from class java.lang.Object

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

Field Detail

size

private final int size

number of elements in the array

vmArray

private final RVMArray vmArray

type of the array

reg

private final Register reg

the register holding the array reference

ir

private final IR ir

the governing IR

Constructor Detail

ShortArrayReplacer

private ShortArrayReplacer(Register r,
                           RVMArray a,
                           int s,
                           IR i)

Parameters:

r - the register holding the array reference

a - the type of the array to replace

s - the size of the array to replace

i - the IR

Method Detail

getReplacer

public static ShortArrayReplacer getReplacer(Instruction inst,
                                             IR ir)

Returns an object representing this transformation for a given allocation site.

Parameters:

inst - the allocation site

ir - the governing IR

Returns:

the object, or null if illegal

transform

public void transform()

Description copied from interface: AggregateReplacer

Perform the transformation

Specified by:

transform in interface AggregateReplacer

transform2

private void transform2(Register reg,
                        Instruction defI,
                        RegisterOperand[] scalars)

scalarReplace

private void scalarReplace(RegisterOperand use,
                           RegisterOperand[] scalars,
                           Set<Register> visited)

Replace a given use of an array with its scalar equivalent.

Parameters:

use - the use to replace

scalars - an array of scalar register operands to replace the array with

visited - TODO currently useless. Is this parameter necessary or should it be removed?

containsUnsupportedUse

private static boolean containsUnsupportedUse(IR ir,
                                              Register reg,
                                              int size,
                                              RVMArray vmArray,
                                              Set<Register> visited)

Some cases we don't handle yet. TODO: handle them.

Parameters:

ir - the governing IR

reg - the register in question

size - the size of the array to scalar replace.

vmArray - the array to replace

visited - the registers that were already visited

Returns:

whether the IR contains an unsupported use