sandmark.obfuscate.boolsplitter.dtree
Class Node

java.lang.Object
  |
  +--sandmark.obfuscate.boolsplitter.dtree.Node

Direct Known Subclasses:

Expr, Stmt, Tree

public abstract class Node

extends java.lang.Object

Node represents a node in an expression tree. Each Node has a value number and a key associated with it. The value number is used to eliminate statements and expressions that have the same value (PRE). Statements and expressions of the same value will be mapped to the same value number.

See Also:

Expr, Stmt, Tree

Field Summary

(package private) int	key
protected Node	parent
(package private) int	valueNumber

Constructor Summary

Node()
Constructor.

Method Summary

Block	block() Returns the basic block in which this Node resides.
void	cleanup() Cleans up this node so that it is independent of the expression tree in which it resides.
abstract void	cleanupOnly() Clean up this Node only.
protected Node	copyInto(Node node) Copies the contents of one Node into another.
boolean	hasParent()
int	key() A Node's key represents an integer value that can be used by an algorithm to mark this node.
Node	parent()
void	replaceWith(Node node) Replaces this node with another and perform cleanup.
void	replaceWith(Node node, boolean cleanup) Replaces this Node with node in its (this's) tree.
void	setKey(int key)
void	setParent(Node parent) Sets the parent Node of this Node.
void	setValueNumber(int valueNumber) Sets this Node's value number.
java.lang.String	toString()
int	valueNumber() Returns this Node's value number.
abstract void	visit(TreeVisitor visitor)
void	visitChildren(TreeVisitor visitor)
abstract void	visitForceChildren(TreeVisitor visitor) Visit the children of this node.
void	visitOnly(TreeVisitor visitor)

Methods inherited from class java.lang.Object

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

Field Detail

parent

protected Node parent

key

int key

valueNumber

int valueNumber

Constructor Detail

Node

public Node()

Constructor.

Method Detail

valueNumber

public int valueNumber()

Returns this Node's value number.

setValueNumber

public void setValueNumber(int valueNumber)

Sets this Node's value number.

key

public int key()

A Node's key represents an integer value that can be used by an algorithm to mark this node. For instance, when dead code elimination is performed a Node is marked as DEAD or ALIVE.

setKey

public void setKey(int key)

visitForceChildren

public abstract void visitForceChildren(TreeVisitor visitor)

Visit the children of this node. Not all Nodes will have children to visit.

visit

public abstract void visit(TreeVisitor visitor)

visitChildren

public void visitChildren(TreeVisitor visitor)

visitOnly

public void visitOnly(TreeVisitor visitor)

block

public Block block()

Returns the basic block in which this Node resides.

setParent

public void setParent(Node parent)

Sets the parent Node of this Node.

hasParent

public boolean hasParent()

parent

public Node parent()

copyInto

protected Node copyInto(Node node)

Copies the contents of one Node into another.

Parameters:

node - A Node from which to copy.

Returns:

node containing the contents of this Node.

cleanupOnly

public abstract void cleanupOnly()

Clean up this Node only. Does not effect its children nodes.

cleanup

public void cleanup()

Cleans up this node so that it is independent of the expression tree in which it resides. This is usually performed before a Node is moved from one part of an expression tree to another.

Traverse the Tree starting at this Node. Remove the parent of each node and perform any Node-specific cleanup (see cleanupOnly). Sets various pointers to null so that they eventually may be garbage collected.

replaceWith

public void replaceWith(Node node)

Replaces this node with another and perform cleanup.

replaceWith

public void replaceWith(Node node,
                        boolean cleanup)

Replaces this Node with node in its (this's) tree.

Parameters:

node - The Node with which to replace.

cleanup - Do we perform cleanup on the tree?

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

Returns:

A textual representation of this Node.