source: webkit/trunk/JavaScriptCore/runtime/JSStaticScopeObject.h@ 48593

Last change on this file since 48593 was 47022, checked in by [email protected], 16 years ago

Stack overflow crash in JavaScript garbage collector mark pass
​https://bugs.webkit.org/show_bug.cgi?id=12216

Reviewed by Gavin Barraclough and Sam Weinig

Make the GC mark phase iterative by using an explicit mark stack.
To do this marking any single object is performed in multiple stages

  • The object is appended to the MarkStack, this sets the marked bit for the object using the new markDirect() function, and then returns
  • When the MarkStack is drain()ed the object is popped off the stack and markChildren(MarkStack&) is called on the object to collect all of its children. drain() then repeats until the stack is empty.

Additionally I renamed a number of methods from 'mark' to 'markAggregate'
in order to make it more clear that marking of those object was not
going to result in an actual recursive mark.
File size: 2.9 KB
Line 
1/*
2 * Copyright (C) 2008, 2009 Apple Inc. All Rights Reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#ifndef JSStaticScopeObject_h
27#define JSStaticScopeObject_h
28
29#include "JSVariableObject.h"
30
31namespace JSC{
32
33 class JSStaticScopeObject : public JSVariableObject {
34 protected:
35 using JSVariableObject::JSVariableObjectData;
36 struct JSStaticScopeObjectData : public JSVariableObjectData {
37 JSStaticScopeObjectData()
38 : JSVariableObjectData(&symbolTable, &registerStore + 1)
39 {
40 }
41 SymbolTable symbolTable;
42 Register registerStore;
43 };
44
45 public:
46 JSStaticScopeObject(ExecState* exec, const Identifier& ident, JSValue value, unsigned attributes)
47 : JSVariableObject(exec->globalData().staticScopeStructure, new JSStaticScopeObjectData())
48 {
49 d()->registerStore = value;
50 symbolTable().add(ident.ustring().rep(), SymbolTableEntry(-1, attributes));
51 }
52 virtual ~JSStaticScopeObject();
53 virtual void markChildren(MarkStack&);
54 bool isDynamicScope() const;
55 virtual JSObject* toThisObject(ExecState*) const;
56 virtual bool getOwnPropertySlot(ExecState*, const Identifier&, PropertySlot&);
57 virtual void put(ExecState*, const Identifier&, JSValue, PutPropertySlot&);
58 void putWithAttributes(ExecState*, const Identifier&, JSValue, unsigned attributes);
59
60 static PassRefPtr<Structure> createStructure(JSValue proto) { return Structure::create(proto, TypeInfo(ObjectType, NeedsThisConversion)); }
61
62 private:
63 JSStaticScopeObjectData* d() { return static_cast<JSStaticScopeObjectData*>(JSVariableObject::d); }
64 };
65
66}
67
68#endif // JSStaticScopeObject_h
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