org.mozilla.javascript.Node Maven / Gradle / Ivy
Go to download
Rhino is an open-source implementation of JavaScript written entirely in Java. It is typically embedded into Java applications to provide scripting to end users.
/* -*- Mode: java; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
*
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0
*
* The contents of this file are subject to the Mozilla 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/MPL/
*
* 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 the Initial Developer are Copyright (C) 1997-1999
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Norris Boyd
* Roshan James
* Roger Lawrence
* Mike McCabe
*
* Alternatively, the contents of this file may be used under the terms of
* the GNU General Public License Version 2 or later (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
* MPL, indicate your decision by deleting the provisions above and replacing
* 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 MPL or the GPL.
*
* ***** END LICENSE BLOCK ***** */
package org.mozilla.javascript;
import java.util.Map;
import java.util.LinkedHashMap;
import java.util.Iterator;
import java.util.Collections;
/**
* 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
CONTROL_BLOCK_PROP = 18, // flags a control block that can drop off
PARENTHESIZED_PROP = 19, // expression is parenthesized
GENERATOR_END_PROP = 20,
DESTRUCTURING_ARRAY_LENGTH = 21,
DESTRUCTURING_NAMES= 22,
LAST_PROP = 22;
// 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;
Node.Scope scope;
}
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;
}
static class Symbol {
Symbol(int declType, String name) {
this.declType = declType;
this.name = name;
this.index = -1;
}
/**
* One of Token.FUNCTION, Token.LP (for parameters), Token.VAR,
* Token.LET, or Token.CONST
*/
int declType;
int index;
String name;
Node.Scope containingTable;
}
static class Scope extends Jump {
public Scope(int nodeType) {
super(nodeType);
}
public Scope(int nodeType, int lineno) {
super(nodeType, lineno);
}
public Scope(int nodeType, Node n, int lineno) {
super(nodeType, n, lineno);
}
/*
* Creates a new scope node, moving symbol table information
* from "scope" to the new node, and making "scope" a nested
* scope contained by the new node.
* Useful for injecting a new scope in a scope chain.
*/
public static Scope splitScope(Scope scope) {
Scope result = new Scope(scope.getType());
result.symbolTable = scope.symbolTable;
scope.symbolTable = null;
result.parent = scope.parent;
scope.parent = result;
result.top = scope.top;
return result;
}
public static void joinScopes(Scope source, Scope dest) {
source.ensureSymbolTable();
dest.ensureSymbolTable();
if (!Collections.disjoint(source.symbolTable.keySet(),
dest.symbolTable.keySet()))
{
throw Kit.codeBug();
}
dest.symbolTable.putAll(source.symbolTable);
}
public void setParent(Scope parent) {
this.parent = parent;
this.top = parent == null ? (ScriptOrFnNode)this : parent.top;
}
public Scope getParentScope() {
return parent;
}
public Scope getDefiningScope(String name) {
for (Scope sn=this; sn != null; sn = sn.parent) {
if (sn.symbolTable == null)
continue;
if (sn.symbolTable.containsKey(name))
return sn;
}
return null;
}
public Symbol getSymbol(String name) {
return symbolTable == null ? null : symbolTable.get(name);
}
public void putSymbol(String name, Symbol symbol) {
ensureSymbolTable();
symbolTable.put(name, symbol);
symbol.containingTable = this;
top.addSymbol(symbol);
}
public Map getSymbolTable() {
return symbolTable;
}
private void ensureSymbolTable() {
if (symbolTable == null) {
symbolTable = new LinkedHashMap(5);
}
}
// Use LinkedHashMap so that the iteration order is the insertion order
protected LinkedHashMap symbolTable;
private Scope parent;
private ScriptOrFnNode top;
}
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) {
Node prev = getChildBefore(child);
if (prev == null)
first = first.next;
else
prev.next = child.next;
if (child == last) last = prev;
child.next = null;
}
public void replaceChild(Node child, Node newChild) {
newChild.next = child.next;
if (child == first) {
first = newChild;
} else {
Node prev = getChildBefore(child);
prev.next = newChild;
}
if (child == last)
last = newChild;
child.next = null;
}
public void replaceChildAfter(Node prevChild, Node newChild) {
Node child = prevChild.next;
newChild.next = child.next;
prevChild.next = newChild;
if (child == last)
last = newChild;
child.next = null;
}
private static final String propToString(int propType)
{
if (Token.printTrees) {
// If Context.printTrees is false, the compiler
// can remove all these strings.
switch (propType) {
case FUNCTION_PROP: return "function";
case LOCAL_PROP: return "local";
case LOCAL_BLOCK_PROP: return "local_block";
case REGEXP_PROP: return "regexp";
case CASEARRAY_PROP: return "casearray";
case TARGETBLOCK_PROP: return "targetblock";
case VARIABLE_PROP: return "variable";
case ISNUMBER_PROP: return "isnumber";
case DIRECTCALL_PROP: return "directcall";
case SPECIALCALL_PROP: return "specialcall";
case SKIP_INDEXES_PROP: return "skip_indexes";
case OBJECT_IDS_PROP: return "object_ids_prop";
case INCRDECR_PROP: return "incrdecr_prop";
case CATCH_SCOPE_PROP: return "catch_scope_prop";
case LABEL_ID_PROP: return "label_id_prop";
case MEMBER_TYPE_PROP: return "member_type_prop";
case NAME_PROP: return "name_prop";
case CONTROL_BLOCK_PROP: return "control_block_prop";
case PARENTHESIZED_PROP: return "parenthesized_prop";
case GENERATOR_END_PROP: return "generator_end";
case DESTRUCTURING_ARRAY_LENGTH:
return "destructuring_array_length";
case DESTRUCTURING_NAMES:return "destructuring_names";
default: Kit.codeBug();
}
}
return null;
}
private PropListItem lookupProperty(int propType)
{
PropListItem x = propListHead;
while (x != null && propType != x.type) {
x = x.next;
}
return x;
}
private PropListItem ensureProperty(int propType)
{
PropListItem item = lookupProperty(propType);
if (item == null) {
item = new PropListItem();
item.type = propType;
item.next = propListHead;
propListHead = item;
}
return item;
}
public void removeProp(int propType)
{
PropListItem x = propListHead;
if (x != null) {
PropListItem prev = null;
while (x.type != propType) {
prev = x;
x = x.next;
if (x == null) { return; }
}
if (prev == null) {
propListHead = x.next;
} else {
prev.next = x.next;
}
}
}
public Object getProp(int propType)
{
PropListItem item = lookupProperty(propType);
if (item == null) { return null; }
return item.objectValue;
}
public int getIntProp(int propType, int defaultValue)
{
PropListItem item = lookupProperty(propType);
if (item == null) { return defaultValue; }
return item.intValue;
}
public int getExistingIntProp(int propType)
{
PropListItem item = lookupProperty(propType);
if (item == null) { Kit.codeBug(); }
return item.intValue;
}
public void putProp(int propType, Object prop)
{
if (prop == null) {
removeProp(propType);
} else {
PropListItem item = ensureProperty(propType);
item.objectValue = prop;
}
}
public void putIntProp(int propType, int prop)
{
PropListItem item = ensureProperty(propType);
item.intValue = prop;
}
public int getLineno() {
return lineno;
}
/** Can only be called when getType() == Token.NUMBER */
public final double getDouble() {
return ((NumberNode)this).number;
}
public final void setDouble(double number) {
((NumberNode)this).number = number;
}
/** Can only be called when node has String context. */
public final String getString() {
return ((StringNode)this).str;
}
/** Can only be called when node has String context. */
public final void setString(String s) {
if (s == null) Kit.codeBug();
((StringNode)this).str = s;
}
/** Can only be called when node has String context. */
public final Scope getScope() {
return ((StringNode)this).scope;
}
/** Can only be called when node has String context. */
public final void setScope(Scope s) {
if (s == null) Kit.codeBug();
if (!(this instanceof StringNode)) {
throw Kit.codeBug();
}
((StringNode)this).scope = s;
}
public static Node newTarget()
{
return new Node(Token.TARGET);
}
public final int labelId()
{
if (type != Token.TARGET && type != Token.YIELD) Kit.codeBug();
return getIntProp(LABEL_ID_PROP, -1);
}
public void labelId(int labelId)
{
if (type != Token.TARGET && type != Token.YIELD) Kit.codeBug();
putIntProp(LABEL_ID_PROP, labelId);
}
/**
* Does consistent-return analysis on the function body when strict mode is
* enabled.
*
* function (x) { return (x+1) }
* is ok, but
* function (x) { if (x < 0) return (x+1); }
* is not becuase the function can potentially return a value when the
* condition is satisfied and if not, the function does not explicitly
* return value.
*
* This extends to checking mismatches such as "return" and "return "
* used in the same function. Warnings are not emitted if inconsistent
* returns exist in code that can be statically shown to be unreachable.
* Ex.
* function (x) { while (true) { ... if (..) { return value } ... } }
* emits no warning. However if the loop had a break statement, then a
* warning would be emitted.
*
* The consistency analysis looks at control structures such as loops, ifs,
* switch, try-catch-finally blocks, examines the reachable code paths and
* warns the user about an inconsistent set of termination possibilities.
*
* Caveat: Since the parser flattens many control structures into almost
* straight-line code with gotos, it makes such analysis hard. Hence this
* analyser is written to taken advantage of patterns of code generated by
* the parser (for loops, try blocks and such) and does not do a full
* control flow analysis of the gotos and break/continue statements.
* Future changes to the parser will affect this analysis.
*/
/**
* These flags enumerate the possible ways a statement/function can
* terminate. These flags are used by endCheck() and by the Parser to
* detect inconsistent return usage.
*
* END_UNREACHED is reserved for code paths that are assumed to always be
* able to execute (example: throw, continue)
*
* END_DROPS_OFF indicates if the statement can transfer control to the
* next one. Statement such as return dont. A compound statement may have
* some branch that drops off control to the next statement.
*
* END_RETURNS indicates that the statement can return (without arguments)
* END_RETURNS_VALUE indicates that the statement can return a value.
*
* A compound statement such as
* if (condition) {
* return value;
* }
* Will be detected as (END_DROPS_OFF | END_RETURN_VALUE) by endCheck()
*/
static final int END_UNREACHED = 0;
static final int END_DROPS_OFF = 1;
static final int END_RETURNS = 2;
static final int END_RETURNS_VALUE = 4;
static final int END_YIELDS = 8;
/**
* Checks that every return usage in a function body is consistent with the
* requirements of strict-mode.
* @return true if the function satisfies strict mode requirement.
*/
public boolean hasConsistentReturnUsage()
{
int n = endCheck();
return (n & END_RETURNS_VALUE) == 0 ||
(n & (END_DROPS_OFF|END_RETURNS|END_YIELDS)) == 0;
}
/**
* Returns in the then and else blocks must be consistent with each other.
* If there is no else block, then the return statement can fall through.
* @return logical OR of END_* flags
*/
private int endCheckIf()
{
Node th, el;
int rv = END_UNREACHED;
th = next;
el = ((Jump)this).target;
rv = th.endCheck();
if (el != null)
rv |= el.endCheck();
else
rv |= END_DROPS_OFF;
return rv;
}
/**
* Consistency of return statements is checked between the case statements.
* If there is no default, then the switch can fall through. If there is a
* default,we check to see if all code paths in the default return or if
* there is a code path that can fall through.
* @return logical OR of END_* flags
*/
private int endCheckSwitch()
{
Node n;
int rv = END_UNREACHED;
// examine the cases
for (n = first.next; n != null; n = n.next)
{
if (n.type == Token.CASE) {
rv |= ((Jump)n).target.endCheck();
} else
break;
}
// we don't care how the cases drop into each other
rv &= ~END_DROPS_OFF;
// examine the default
n = ((Jump)this).getDefault();
if (n != null)
rv |= n.endCheck();
else
rv |= END_DROPS_OFF;
// remove the switch block
rv |= getIntProp(CONTROL_BLOCK_PROP, END_UNREACHED);
return rv;
}
/**
* If the block has a finally, return consistency is checked in the
* finally block. If all code paths in the finally returns, then the
* returns in the try-catch blocks don't matter. If there is a code path
* that does not return or if there is no finally block, the returns
* of the try and catch blocks are checked for mismatch.
* @return logical OR of END_* flags
*/
private int endCheckTry()
{
Node n;
int rv = END_UNREACHED;
// check the finally if it exists
n = ((Jump)this).getFinally();
if(n != null) {
rv = n.next.first.endCheck();
} else {
rv = END_DROPS_OFF;
}
// if the finally block always returns, then none of the returns
// in the try or catch blocks matter
if ((rv & END_DROPS_OFF) != 0) {
rv &= ~END_DROPS_OFF;
// examine the try block
rv |= first.endCheck();
// check each catch block
n = ((Jump)this).target;
if (n != null)
{
// point to the first catch_scope
for (n = n.next.first; n != null; n = n.next.next)
{
// check the block of user code in the catch_scope
rv |= n.next.first.next.first.endCheck();
}
}
}
return rv;
}
/**
* Return statement in the loop body must be consistent. The default
* assumption for any kind of a loop is that it will eventually terminate.
* The only exception is a loop with a constant true condition. Code that
* follows such a loop is examined only if one can statically determine
* that there is a break out of the loop.
* for(<> ; <>; <>) {}
* for(<> in <> ) {}
* while(<>) { }
* do { } while(<>)
* @return logical OR of END_* flags
*/
private int endCheckLoop()
{
Node n;
int rv = END_UNREACHED;
// To find the loop body, we look at the second to last node of the
// loop node, which should be the predicate that the loop should
// satisfy.
// The target of the predicate is the loop-body for all 4 kinds of
// loops.
for (n = first; n.next != last; n = n.next) {
/* skip */
}
if (n.type != Token.IFEQ)
return END_DROPS_OFF;
// The target's next is the loop body block
rv = ((Jump)n).target.next.endCheck();
// check to see if the loop condition is true
if (n.first.type == Token.TRUE)
rv &= ~END_DROPS_OFF;
// look for effect of breaks
rv |= getIntProp(CONTROL_BLOCK_PROP, END_UNREACHED);
return rv;
}
/**
* A general block of code is examined statement by statement. If any
* statement (even compound ones) returns in all branches, then subsequent
* statements are not examined.
* @return logical OR of END_* flags
*/
private int endCheckBlock()
{
Node n;
int rv = END_DROPS_OFF;
// check each statment and if the statement can continue onto the next
// one, then check the next statement
for (n=first; ((rv & END_DROPS_OFF) != 0) && n != null; n = n.next)
{
rv &= ~END_DROPS_OFF;
rv |= n.endCheck();
}
return rv;
}
/**
* A labelled statement implies that there maybe a break to the label. The
* function processes the labelled statement and then checks the
* CONTROL_BLOCK_PROP property to see if there is ever a break to the
* particular label.
* @return logical OR of END_* flags
*/
private int endCheckLabel()
{
int rv = END_UNREACHED;
rv = next.endCheck();
rv |= getIntProp(CONTROL_BLOCK_PROP, END_UNREACHED);
return rv;
}
/**
* When a break is encountered annotate the statement being broken
* out of by setting its CONTROL_BLOCK_PROP property.
* @return logical OR of END_* flags
*/
private int endCheckBreak()
{
Node n = ((Jump) this).jumpNode;
n.putIntProp(CONTROL_BLOCK_PROP, END_DROPS_OFF);
return END_UNREACHED;
}
/**
* endCheck() examines the body of a function, doing a basic reachability
* analysis and returns a combination of flags END_* flags that indicate
* how the function execution can terminate. These constitute only the
* pessimistic set of termination conditions. It is possible that at
* runtime certain code paths will never be actually taken. Hence this
* analysis will flag errors in cases where there may not be errors.
* @return logical OR of END_* flags
*/
private int endCheck()
{
switch(type)
{
case Token.BREAK:
return endCheckBreak();
case Token.EXPR_VOID:
if (this.first != null)
return first.endCheck();
return END_DROPS_OFF;
case Token.YIELD:
return END_YIELDS;
case Token.CONTINUE:
case Token.THROW:
return END_UNREACHED;
case Token.RETURN:
if (this.first != null)
return END_RETURNS_VALUE;
else
return END_RETURNS;
case Token.TARGET:
if (next != null)
return next.endCheck();
else
return END_DROPS_OFF;
case Token.LOOP:
return endCheckLoop();
case Token.LOCAL_BLOCK:
case Token.BLOCK:
// there are several special kinds of blocks
if (first == null)
return END_DROPS_OFF;
switch(first.type) {
case Token.LABEL:
return first.endCheckLabel();
case Token.IFNE:
return first.endCheckIf();
case Token.SWITCH:
return first.endCheckSwitch();
case Token.TRY:
return first.endCheckTry();
default:
return endCheckBlock();
}
default:
return END_DROPS_OFF;
}
}
public boolean hasSideEffects()
{
switch (type) {
case Token.EXPR_VOID:
case Token.COMMA:
if (last != null)
return last.hasSideEffects();
else
return true;
case Token.HOOK:
if (first == null ||
first.next == null ||
first.next.next == null)
Kit.codeBug();
return first.next.hasSideEffects() &&
first.next.next.hasSideEffects();
case Token.ERROR: // Avoid cascaded error messages
case Token.EXPR_RESULT:
case Token.ASSIGN:
case Token.ASSIGN_ADD:
case Token.ASSIGN_SUB:
case Token.ASSIGN_MUL:
case Token.ASSIGN_DIV:
case Token.ASSIGN_MOD:
case Token.ASSIGN_BITOR:
case Token.ASSIGN_BITXOR:
case Token.ASSIGN_BITAND:
case Token.ASSIGN_LSH:
case Token.ASSIGN_RSH:
case Token.ASSIGN_URSH:
case Token.ENTERWITH:
case Token.LEAVEWITH:
case Token.RETURN:
case Token.GOTO:
case Token.IFEQ:
case Token.IFNE:
case Token.NEW:
case Token.DELPROP:
case Token.SETNAME:
case Token.SETPROP:
case Token.SETELEM:
case Token.CALL:
case Token.THROW:
case Token.RETHROW:
case Token.SETVAR:
case Token.CATCH_SCOPE:
case Token.RETURN_RESULT:
case Token.SET_REF:
case Token.DEL_REF:
case Token.REF_CALL:
case Token.TRY:
case Token.SEMI:
case Token.INC:
case Token.DEC:
case Token.EXPORT:
case Token.IMPORT:
case Token.IF:
case Token.ELSE:
case Token.SWITCH:
case Token.WHILE:
case Token.DO:
case Token.FOR:
case Token.BREAK:
case Token.CONTINUE:
case Token.VAR:
case Token.CONST:
case Token.LET:
case Token.LETEXPR:
case Token.WITH:
case Token.WITHEXPR:
case Token.CATCH:
case Token.FINALLY:
case Token.BLOCK:
case Token.LABEL:
case Token.TARGET:
case Token.LOOP:
case Token.JSR:
case Token.SETPROP_OP:
case Token.SETELEM_OP:
case Token.LOCAL_BLOCK:
case Token.SET_REF_OP:
case Token.YIELD:
return true;
default:
return false;
}
}
public String toString()
{
if (Token.printTrees) {
StringBuffer sb = new StringBuffer();
toString(new ObjToIntMap(), sb);
return sb.toString();
}
return String.valueOf(type);
}
private void toString(ObjToIntMap printIds, StringBuffer sb)
{
if (Token.printTrees) {
sb.append(Token.name(type));
if (this instanceof StringNode) {
sb.append(' ');
sb.append(getString());
Scope scope = getScope();
if (scope != null) {
sb.append("[scope: ");
appendPrintId(scope, printIds, sb);
sb.append("]");
}
} else if (this instanceof Node.Scope) {
if (this instanceof ScriptOrFnNode) {
ScriptOrFnNode sof = (ScriptOrFnNode)this;
if (this instanceof FunctionNode) {
FunctionNode fn = (FunctionNode)this;
sb.append(' ');
sb.append(fn.getFunctionName());
}
sb.append(" [source name: ");
sb.append(sof.getSourceName());
sb.append("] [encoded source length: ");
sb.append(sof.getEncodedSourceEnd()
- sof.getEncodedSourceStart());
sb.append("] [base line: ");
sb.append(sof.getBaseLineno());
sb.append("] [end line: ");
sb.append(sof.getEndLineno());
sb.append(']');
}
if (((Node.Scope)this).symbolTable != null) {
sb.append(" [scope ");
appendPrintId(this, printIds, sb);
sb.append(": ");
Iterator iter = ((Node.Scope) this).symbolTable.keySet()
.iterator();
while (iter.hasNext()) {
sb.append(iter.next());
sb.append(" ");
}
sb.append("]");
}
} else if (this instanceof Jump) {
Jump jump = (Jump)this;
if (type == Token.BREAK || type == Token.CONTINUE) {
sb.append(" [label: ");
appendPrintId(jump.getJumpStatement(), printIds, sb);
sb.append(']');
} else if (type == Token.TRY) {
Node catchNode = jump.target;
Node finallyTarget = jump.getFinally();
if (catchNode != null) {
sb.append(" [catch: ");
appendPrintId(catchNode, printIds, sb);
sb.append(']');
}
if (finallyTarget != null) {
sb.append(" [finally: ");
appendPrintId(finallyTarget, printIds, sb);
sb.append(']');
}
} else if (type == Token.LABEL || type == Token.LOOP
|| type == Token.SWITCH)
{
sb.append(" [break: ");
appendPrintId(jump.target, printIds, sb);
sb.append(']');
if (type == Token.LOOP) {
sb.append(" [continue: ");
appendPrintId(jump.getContinue(), printIds, sb);
sb.append(']');
}
} else {
sb.append(" [target: ");
appendPrintId(jump.target, printIds, sb);
sb.append(']');
}
} else if (type == Token.NUMBER) {
sb.append(' ');
sb.append(getDouble());
} else if (type == Token.TARGET) {
sb.append(' ');
appendPrintId(this, printIds, sb);
}
if (lineno != -1) {
sb.append(' ');
sb.append(lineno);
}
for (PropListItem x = propListHead; x != null; x = x.next) {
int type = x.type;
sb.append(" [");
sb.append(propToString(type));
sb.append(": ");
String value;
switch (type) {
case TARGETBLOCK_PROP : // can't add this as it recurses
value = "target block property";
break;
case LOCAL_BLOCK_PROP : // can't add this as it is dull
value = "last local block";
break;
case ISNUMBER_PROP:
switch (x.intValue) {
case BOTH:
value = "both";
break;
case RIGHT:
value = "right";
break;
case LEFT:
value = "left";
break;
default:
throw Kit.codeBug();
}
break;
case SPECIALCALL_PROP:
switch (x.intValue) {
case SPECIALCALL_EVAL:
value = "eval";
break;
case SPECIALCALL_WITH:
value = "with";
break;
default:
// NON_SPECIALCALL should not be stored
throw Kit.codeBug();
}
break;
case OBJECT_IDS_PROP: {
Object[] a = (Object[]) x.objectValue;
value = "[";
for (int i=0; i < a.length; i++) {
value += a[i].toString();
if (i+1 < a.length)
value += ", ";
}
value += "]";
break;
}
default :
Object obj = x.objectValue;
if (obj != null) {
value = obj.toString();
} else {
value = String.valueOf(x.intValue);
}
break;
}
sb.append(value);
sb.append(']');
}
}
}
public String toStringTree(ScriptOrFnNode treeTop) {
if (Token.printTrees) {
StringBuffer sb = new StringBuffer();
toStringTreeHelper(treeTop, this, null, 0, sb);
return sb.toString();
}
return null;
}
private static void toStringTreeHelper(ScriptOrFnNode treeTop, Node n,
ObjToIntMap printIds,
int level, StringBuffer sb)
{
if (Token.printTrees) {
if (printIds == null) {
printIds = new ObjToIntMap();
generatePrintIds(treeTop, printIds);
}
for (int i = 0; i != level; ++i) {
sb.append(" ");
}
n.toString(printIds, sb);
sb.append('\n');
for (Node cursor = n.getFirstChild(); cursor != null;
cursor = cursor.getNext())
{
if (cursor.getType() == Token.FUNCTION) {
int fnIndex = cursor.getExistingIntProp(Node.FUNCTION_PROP);
FunctionNode fn = treeTop.getFunctionNode(fnIndex);
toStringTreeHelper(fn, fn, null, level + 1, sb);
} else {
toStringTreeHelper(treeTop, cursor, printIds, level + 1, sb);
}
}
}
}
private static void generatePrintIds(Node n, ObjToIntMap map)
{
if (Token.printTrees) {
map.put(n, map.size());
for (Node cursor = n.getFirstChild(); cursor != null;
cursor = cursor.getNext())
{
generatePrintIds(cursor, map);
}
}
}
private static void appendPrintId(Node n, ObjToIntMap printIds,
StringBuffer sb)
{
if (Token.printTrees) {
if (n != null) {
int id = printIds.get(n, -1);
sb.append('#');
if (id != -1) {
sb.append(id + 1);
} else {
sb.append("");
}
}
}
}
int type; // type of the node; Token.NAME for example
Node next; // next sibling
private Node first; // first element of a linked list of children
private Node last; // last element of a linked list of children
protected int lineno = -1;
/**
* Linked list of properties. Since vast majority of nodes would have
* no more then 2 properties, linked list saves memory and provides
* fast lookup. If this does not holds, propListHead can be replaced
* by UintMap.
*/
private PropListItem propListHead;
}