1 // -*- mode: c++; c-basic-offset: 4 -*- 2 /* 3 * Copyright (C) 2008 Apple Inc. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY 15 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 17 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR 18 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 19 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 20 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 21 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY 22 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 24 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27 #ifndef JSTypeInfo_h 28 #define JSTypeInfo_h 29 30 // This file would be called TypeInfo.h, but that conflicts with <typeinfo.h> 31 // in the STL on systems without case-sensitive file systems. 32 33 #include "JSType.h" 34 35 namespace JSC { 36 37 // WebCore uses MasqueradesAsUndefined to make document.all and style.filter undetectable. 38 static const unsigned MasqueradesAsUndefined = 1; 39 static const unsigned ImplementsHasInstance = 1 << 1; 40 static const unsigned OverridesHasInstance = 1 << 2; 41 static const unsigned ImplementsDefaultHasInstance = 1 << 3; 42 static const unsigned NeedsThisConversion = 1 << 4; 43 static const unsigned OverridesGetOwnPropertySlot = 1 << 5; 44 static const unsigned OverridesMarkChildren = 1 << 6; 45 static const unsigned OverridesGetPropertyNames = 1 << 7; 46 47 class TypeInfo { 48 friend class JIT; 49 public: 50 TypeInfo(JSType type, unsigned flags = 0) 51 : m_type(type) 52 { 53 // ImplementsDefaultHasInstance means (ImplementsHasInstance & !OverridesHasInstance) 54 if ((flags & (ImplementsHasInstance | OverridesHasInstance)) == ImplementsHasInstance) 55 m_flags = flags | ImplementsDefaultHasInstance; 56 else 57 m_flags = flags; 58 } 59 60 JSType type() const { return m_type; } 61 62 bool masqueradesAsUndefined() const { return m_flags & MasqueradesAsUndefined; } 63 bool implementsHasInstance() const { return m_flags & ImplementsHasInstance; } 64 bool overridesHasInstance() const { return m_flags & OverridesHasInstance; } 65 bool needsThisConversion() const { return m_flags & NeedsThisConversion; } 66 bool overridesGetOwnPropertySlot() const { return m_flags & OverridesGetOwnPropertySlot; } 67 bool overridesMarkChildren() const { return m_flags & OverridesMarkChildren; } 68 bool overridesGetPropertyNames() const { return m_flags & OverridesGetPropertyNames; } 69 unsigned flags() const { return m_flags; } 70 71 private: 72 JSType m_type; 73 unsigned m_flags; 74 }; 75 76 } 77 78 #endif // JSTypeInfo_h 79