harpoon.IR.Tree
Class DATUM

java.lang.Object
  harpoon.IR.Tree.Tree
      harpoon.IR.Tree.Stm
          harpoon.IR.Tree.DATUM

All Implemented Interfaces:

HCodeElement, HDataElement

public class DATUM
extends Stm
implements HDataElement

DATUM objects are statements which write a value to memory at the time when a program is loaded. The location written is calculated using this formula:

         location = base + offset
 
 where 
         base   = location of nearest LABEL, l,  which precedes this DATUM
         offset = the total size of all instructions between l and this DATUM
                      
 

Version:

$Id: DATUM.java,v 1.4 2002/04/10 03:05:44 cananian Exp $

Author:

Duncan Bryce <duncan@lcs.mit.edu>

Nested Class Summary

Nested classes/interfaces inherited from class harpoon.IR.Tree.Tree

Tree.CloneCallback

Field Summary

boolean

initialized If false, the memory is not initialized; instead it is reserved with an unspecified value.

Fields inherited from class harpoon.IR.Tree.Tree

arrayFactory, child

Constructor Summary

DATUM(TreeFactory tf, HCodeElement source, Exp data)
Class constructor.

DATUM(TreeFactory tf, HCodeElement source, int type)
Class constructor.

DATUM(TreeFactory tf, HCodeElement source, int bitwidth, boolean signed)
Class constructor.

Method Summary

void	accept(TreeVisitor v) Accept a visitor
Stm	build(TreeFactory tf, ExpList kids)
Exp	getData() Returns the expression to write to memory.
int	kind() Return an integer enumeration of the kind of this Tree.
Tree	rename(TreeFactory tf, TempMap tm, Tree.CloneCallback cb) Rename while cloning a subtree.
void	setData(Exp data) Sets the expression to write to memory.
String	toString()

Methods inherited from class harpoon.IR.Tree.Stm

build, isNop, linearize, toStm

Methods inherited from class harpoon.IR.Tree.Tree

clone, clone, getChild, getFactory, getFirstChild, getID, getLineNumber, getParent, getSibling, getSourceFile, hashCode, kids, rename, replace, setChild, unlink

Methods inherited from class java.lang.Object

equals, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface harpoon.ClassFile.HDataElement

getID, getSourceFile

Field Detail

initialized

public final boolean initialized

If false, the memory is not initialized; instead it is reserved with an unspecified value.

Constructor Detail

DATUM

public DATUM(TreeFactory tf,
             HCodeElement source,
             Exp data)

Class constructor. The parameter
data must be an instance of either harpoon.IR.Tree.CONST or harpoon.IR.Tree.NAME. Passing null for the parameter data reserves a word of memory at the location of this DATUM without assigning it a value.

DATUM

public DATUM(TreeFactory tf,
             HCodeElement source,
             int type)

Class constructor. Reserves memory at the location of this DATUM of the size of the specified type without assigning it a value.

DATUM

public DATUM(TreeFactory tf,
             HCodeElement source,
             int bitwidth,
             boolean signed)

Class constructor. Reserves memory at the location of this DATUM of the specified small without assigning it a value.

Method Detail

getData

public Exp getData()

Returns the expression to write to memory. Never null.

setData

public void setData(Exp data)

Sets the expression to write to memory. Never null.

kind

public int kind()

Description copied from class: Tree

Return an integer enumeration of the kind of this Tree. The enumerated values are defined in TreeKind.

Specified by:

kind in class Tree

build

public Stm build(TreeFactory tf,
                 ExpList kids)

Specified by:

build in class Stm

accept

public void accept(TreeVisitor v)

Accept a visitor

Specified by:

accept in class Tree

rename

public Tree rename(TreeFactory tf,
                   TempMap tm,
                   Tree.CloneCallback cb)

Description copied from class: Tree

Rename while cloning a subtree. This node and all child nodes are cloned; the 'temp' information of all TEMP nodes are renamed according to the supplied TempMap. Note that Temps not belonging to this.getFactory().tempFactory() are not affected. The callback() method of the supplied CloneCallback is invoked once on each subtree cloned, starting from the leaves and working back to the root in a post-order depth-first manner.

Specified by:

rename in class Tree

toString

public String toString()

Overrides:

toString in class Object