/* -*- Mode: java; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- * * The contents of this file are subject to the Netscape Public * License Version 1.1 (the "License"); you may not use this file * except in compliance with the License. You may obtain a copy of * the License at http://www.mozilla.org/NPL/ * * Software distributed under the License is distributed on an "AS * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or * implied. See the License for the specific language governing * rights and limitations under the License. * * The Original Code is Rhino code, released * May 6, 1999. * * The Initial Developer of the Original Code is Netscape * Communications Corporation.  Portions created by Netscape are * Copyright (C) 1997-1999 Netscape Communications Corporation. All * Rights Reserved. * * Contributor(s): * Norris Boyd * Roger Lawrence * Mike McCabe * * Alternatively, the contents of this file may be used under the * terms of the GNU Public License (the "GPL"), in which case the * provisions of the GPL are applicable instead of those above. * If you wish to allow use of your version of this file only * under the terms of the GPL and not to allow others to use your * version of this file under the NPL, indicate your decision by * deleting the provisions above and replace them with the notice * and other provisions required by the GPL.  If you do not delete * the provisions above, a recipient may use your version of this * file under either the NPL or the GPL. */package org.mozilla.javascript;/** * This class implements the root of the intermediate representation. * * @author Norris Boyd * @author Mike McCabe */public class Node{    public static final int        FUNCTION_PROP      =  1,        LOCAL_PROP         =  2,        LOCAL_BLOCK_PROP   =  3,        REGEXP_PROP        =  4,        CASEARRAY_PROP     =  5,    /*        the following properties are defined and manipulated by the        optimizer -        TARGETBLOCK_PROP - the block referenced by a branch node        VARIABLE_PROP - the variable referenced by a BIND or NAME node        ISNUMBER_PROP - this node generates code on Number children and                        delivers a Number result (as opposed to Objects)        DIRECTCALL_PROP - this call node should emit code to test the function                          object against the known class and call diret if it                          matches.    */        TARGETBLOCK_PROP   =  6,        VARIABLE_PROP      =  7,        ISNUMBER_PROP      =  8,        DIRECTCALL_PROP    =  9,        SPECIALCALL_PROP   = 10,        SKIP_INDEXES_PROP  = 11, // array of skipped indexes of array literal        OBJECT_IDS_PROP    = 12, // array of properties for object literal        INCRDECR_PROP      = 13, // pre or post type of increment/decerement        CATCH_SCOPE_PROP   = 14, // index of catch scope block in catch        LABEL_ID_PROP      = 15, // label id: code generation uses it        MEMBER_TYPE_PROP   = 16, // type of element access operation        NAME_PROP          = 17, // property name        LAST_PROP          = 17;    // values of ISNUMBER_PROP to specify    // which of the children are Number types    public static final int        BOTH = 0,        LEFT = 1,        RIGHT = 2;    public static final int    // values for SPECIALCALL_PROP        NON_SPECIALCALL  = 0,        SPECIALCALL_EVAL = 1,        SPECIALCALL_WITH = 2;    public static final int   // flags for INCRDECR_PROP        DECR_FLAG = 0x1,        POST_FLAG = 0x2;    public static final int   // flags for MEMBER_TYPE_PROP        PROPERTY_FLAG    = 0x1, // property access: element is valid name        ATTRIBUTE_FLAG   = 0x2, // x.@y or x..@y        DESCENDANTS_FLAG = 0x4; // x..y or x..@i    private static class NumberNode extends Node    {        NumberNode(double number)        {            super(Token.NUMBER);            this.number = number;        }        double number;    }    private static class StringNode extends Node    {        StringNode(int type, String str) {            super(type);            this.str = str;        }        String str;    }    public static class Jump extends Node    {        public Jump(int type)        {            super(type);        }        Jump(int type, int lineno)        {            super(type, lineno);        }        Jump(int type, Node child)        {            super(type, child);        }        Jump(int type, Node child, int lineno)        {            super(type, child, lineno);        }        public final Jump getJumpStatement()        {            if (!(type == Token.BREAK || type == Token.CONTINUE)) Kit.codeBug();            return jumpNode;        }        public final void setJumpStatement(Jump jumpStatement)        {            if (!(type == Token.BREAK || type == Token.CONTINUE)) Kit.codeBug();            if (jumpStatement == null) Kit.codeBug();            if (this.jumpNode != null) Kit.codeBug(); //only once            this.jumpNode = jumpStatement;        }        public final Node getDefault()        {            if (!(type == Token.SWITCH)) Kit.codeBug();            return target2;        }        public final void setDefault(Node defaultTarget)        {            if (!(type == Token.SWITCH)) Kit.codeBug();            if (defaultTarget.type != Token.TARGET) Kit.codeBug();            if (target2 != null) Kit.codeBug(); //only once            target2 = defaultTarget;        }        public final Node getFinally()        {            if (!(type == Token.TRY)) Kit.codeBug();            return target2;        }        public final void setFinally(Node finallyTarget)        {            if (!(type == Token.TRY)) Kit.codeBug();            if (finallyTarget.type != Token.TARGET) Kit.codeBug();            if (target2 != null) Kit.codeBug(); //only once            target2 = finallyTarget;        }        public final Jump getLoop()        {            if (!(type == Token.LABEL)) Kit.codeBug();            return jumpNode;        }        public final void setLoop(Jump loop)        {            if (!(type == Token.LABEL)) Kit.codeBug();            if (loop == null) Kit.codeBug();            if (jumpNode != null) Kit.codeBug(); //only once            jumpNode = loop;        }        public final Node getContinue()        {            if (type != Token.LOOP) Kit.codeBug();            return target2;        }        public final void setContinue(Node continueTarget)        {            if (type != Token.LOOP) Kit.codeBug();            if (continueTarget.type != Token.TARGET) Kit.codeBug();            if (target2 != null) Kit.codeBug(); //only once            target2 = continueTarget;        }        public Node target;        private Node target2;        private Jump jumpNode;    }    private static class PropListItem    {        PropListItem next;        int type;        int intValue;        Object objectValue;    }    public Node(int nodeType) {        type = nodeType;    }    public Node(int nodeType, Node child) {        type = nodeType;        first = last = child;        child.next = null;    }    public Node(int nodeType, Node left, Node right) {        type = nodeType;        first = left;        last = right;        left.next = right;        right.next = null;    }    public Node(int nodeType, Node left, Node mid, Node right) {        type = nodeType;        first = left;        last = right;        left.next = mid;        mid.next = right;        right.next = null;    }    public Node(int nodeType, int line) {        type = nodeType;        lineno = line;    }    public Node(int nodeType, Node child, int line) {        this(nodeType, child);        lineno = line;    }    public Node(int nodeType, Node left, Node right, int line) {        this(nodeType, left, right);        lineno = line;    }    public Node(int nodeType, Node left, Node mid, Node right, int line) {        this(nodeType, left, mid, right);        lineno = line;    }    public static Node newNumber(double number) {        return new NumberNode(number);    }    public static Node newString(String str) {        return new StringNode(Token.STRING, str);    }    public static Node newString(int type, String str) {        return new StringNode(type, str);    }    public int getType() {        return type;    }    public void setType(int type) {        this.type = type;    }    public boolean hasChildren() {        return first != null;    }    public Node getFirstChild() {        return first;    }    public Node getLastChild() {        return last;    }    public Node getNext() {        return next;    }    public Node getChildBefore(Node child) {        if (child == first)            return null;        Node n = first;        while (n.next != child) {            n = n.next;            if (n == null)                throw new RuntimeException("node is not a child");        }        return n;    }    public Node getLastSibling() {        Node n = this;        while (n.next != null) {            n = n.next;        }        return n;    }    public void addChildToFront(Node child) {        child.next = first;        first = child;        if (last == null) {            last = child;        }    }    public void addChildToBack(Node child) {        child.next = null;        if (last == null) {            first = last = child;            return;        }        last.next = child;        last = child;    }    public void addChildrenToFront(Node children) {        Node lastSib = children.getLastSibling();        lastSib.next = first;        first = children;        if (last == null) {            last = lastSib;        }    }    public void addChildrenToBack(Node children) {        if (last != null) {            last.next = children;        }        last = children.getLastSibling();        if (first == null) {            first = children;        }    }    /**     * Add 'child' before 'node'.     */    public void addChildBefore(Node newChild, Node node) {        if (newChild.next != null)            throw new RuntimeException(                      "newChild had siblings in addChildBefore");        if (first == node) {            newChild.next = first;            first = newChild;            return;        }        Node prev = getChildBefore(node);        addChildAfter(newChild, prev);    }    /**     * Add 'child' after 'node'.     */    public void addChildAfter(Node newChild, Node node) {        if (newChild.next != null)            throw new RuntimeException(                      "newChild had siblings in addChildAfter");        newChild.next = node.next;        node.next = newChild;        if (last == node)            last = newChild;    }    public void removeChild(Node child) {