harpoon.Analysis.PreciseGC
Class WriteBarrierInserter

java.lang.Object
  harpoon.Analysis.Transformation.MethodMutator
      harpoon.Analysis.PreciseGC.WriteBarrierInserter

All Implemented Interfaces:

Serializable

public class WriteBarrierInserter
extends MethodMutator

WriteBarrierInserter takes code in Quad form and inserts write barriers for generational garbage collection. Write barriers are inserted before SETs of non-static Object and ASETs of Object arrays. The write barrier used is a call to a native implementation that may be replaced in later passes with a more efficient implementation.

Version:

$Id: WriteBarrierInserter.java,v 1.1 2002/06/25 18:16:22 kkz Exp $

Author:

Karen Zee <kkz@tmi.lcs.mit.edu>

See Also:

Serialized Form

Nested Class Summary

static class	WriteBarrierInserter.DefaultWriteBarrierAnalysis DefaultWriteBarrierAnalysis returns a no- analysis WriteBarrierAnalysis Object that assumes write barriers are needed for all SET and ASETs of object fields.
static interface	WriteBarrierInserter.WriteBarrierAnalysis A WriteBarrierAnalysis maps Codes to Sets of Quads for which write barriers have been deemed unnecessary.

Constructor Summary

WriteBarrierInserter(HCodeFactory parent, Linker linker)
Creates a WriteBarrierInserter using a default no-analysis WriteBarrierAnalysis.

WriteBarrierInserter(HCodeFactory parent, Linker linker, WriteBarrierInserter.WriteBarrierAnalysis wba)
Creates a WriteBarrierInserter.

Method Summary

protected HCode

mutateHCode(HCodeAndMaps input) Override this method to effect transformations on split methods.

Methods inherited from class harpoon.Analysis.Transformation.MethodMutator

cloneHCode, codeFactory, mutateCodeName

Methods inherited from class java.lang.Object

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

Constructor Detail

WriteBarrierInserter

public WriteBarrierInserter(HCodeFactory parent,
                            Linker linker,
                            WriteBarrierInserter.WriteBarrierAnalysis wba)

Creates a WriteBarrierInserter.

WriteBarrierInserter

public WriteBarrierInserter(HCodeFactory parent,
                            Linker linker)

Creates a WriteBarrierInserter using a default no-analysis WriteBarrierAnalysis.

Method Detail

mutateHCode

protected HCode mutateHCode(HCodeAndMaps input)

Description copied from class: MethodMutator

Override this method to effect transformations on split methods.

Overrides:

mutateHCode in class MethodMutator