1/*
2 * Copyright (C) 1999-2001 Harri Porten ([email protected])
3 * Copyright (C) 2001 Peter Kelly ([email protected])
4 * Copyright (C) 2003, 2007, 2008 Apple Inc. All rights reserved.
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Library General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Library General Public License for more details.
15 *
16 * You should have received a copy of the GNU Library General Public License
17 * along with this library; see the file COPYING.LIB. If not, write to
18 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
19 * Boston, MA 02110-1301, USA.
20 *
21 */
22
23#ifndef CallFrame_h
24#define CallFrame_h
25
26#include "JSGlobalData.h"
27#include "RegisterFile.h"
28#include "ScopeChain.h"
29
30namespace JSC {
31
32 class Arguments;
33 class JSActivation;
34 class Interpreter;
35
36 // Represents the current state of script execution.
37 // Passed as the first argument to most functions.
38 class ExecState : private Register {
39 public:
40 JSObject* callee() const { return this[RegisterFile::Callee].object(); }
41 CodeBlock* codeBlock() const { return this[RegisterFile::CodeBlock].Register::codeBlock(); }
42 ScopeChainNode* scopeChain() const
43 {
44 ASSERT(this[RegisterFile::ScopeChain].Register::scopeChain());
45 return this[RegisterFile::ScopeChain].Register::scopeChain();
46 }
47 int argumentCount() const { return this[RegisterFile::ArgumentCount].i(); }
48
49 JSValue thisValue();
50
51 // Global object in which execution began.
52 JSGlobalObject* dynamicGlobalObject();
53
54 // Global object in which the currently executing code was defined.
55 // Differs from dynamicGlobalObject() during function calls across web browser frames.
56 JSGlobalObject* lexicalGlobalObject() const
57 {
58 return scopeChain()->globalObject;
59 }
60
61 // Differs from lexicalGlobalObject because this will have DOM window shell rather than
62 // the actual DOM window, which can't be "this" for security reasons.
63 JSObject* globalThisValue() const
64 {
65 return scopeChain()->globalThis;
66 }
67
68 // FIXME: Elsewhere, we use JSGlobalData* rather than JSGlobalData&.
69 // We should make this more uniform and either use a reference everywhere
70 // or a pointer everywhere.
71 JSGlobalData& globalData() const
72 {
73 ASSERT(scopeChain()->globalData);
74 return *scopeChain()->globalData;
75 }
76
77 // Convenience functions for access to global data.
78 // It takes a few memory references to get from a call frame to the global data
79 // pointer, so these are inefficient, and should be used sparingly in new code.
80 // But they're used in many places in legacy code, so they're not going away any time soon.
81
82 void setException(JSValue exception) { globalData().exception = exception; }
83 void clearException() { globalData().exception = JSValue(); }
84 JSValue exception() const { return globalData().exception; }
85 JSValue* exceptionSlot() { return &globalData().exception; }
86 bool hadException() const { return globalData().exception; }
87
88 const CommonIdentifiers& propertyNames() const { return *globalData().propertyNames; }
89 const MarkedArgumentBuffer& emptyList() const { return *globalData().emptyList; }
90 Interpreter* interpreter() { return globalData().interpreter; }
91 Heap* heap() { return &globalData().heap; }
92#ifndef NDEBUG
93 void dumpCaller();
94#endif
95 static const HashTable* arrayTable(CallFrame* callFrame) { return callFrame->globalData().arrayTable; }
96 static const HashTable* dateTable(CallFrame* callFrame) { return callFrame->globalData().dateTable; }
97 static const HashTable* jsonTable(CallFrame* callFrame) { return callFrame->globalData().jsonTable; }
98 static const HashTable* mathTable(CallFrame* callFrame) { return callFrame->globalData().mathTable; }
99 static const HashTable* numberTable(CallFrame* callFrame) { return callFrame->globalData().numberTable; }
100 static const HashTable* regExpTable(CallFrame* callFrame) { return callFrame->globalData().regExpTable; }
101 static const HashTable* regExpConstructorTable(CallFrame* callFrame) { return callFrame->globalData().regExpConstructorTable; }
102 static const HashTable* stringTable(CallFrame* callFrame) { return callFrame->globalData().stringTable; }
103
104 static CallFrame* create(Register* callFrameBase) { return static_cast<CallFrame*>(callFrameBase); }
105 Register* registers() { return this; }
106
107 CallFrame& operator=(const Register& r) { *static_cast<Register*>(this) = r; return *this; }
108
109 CallFrame* callerFrame() const { return this[RegisterFile::CallerFrame].callFrame(); }
110 Arguments* optionalCalleeArguments() const { return this[RegisterFile::OptionalCalleeArguments].arguments(); }
111 Instruction* returnPC() const { return this[RegisterFile::ReturnPC].vPC(); }
112
113 void setCalleeArguments(JSValue arguments) { static_cast<Register*>(this)[RegisterFile::OptionalCalleeArguments] = arguments; }
114 void setCallerFrame(CallFrame* callerFrame) { static_cast<Register*>(this)[RegisterFile::CallerFrame] = callerFrame; }
115 void setScopeChain(ScopeChainNode* scopeChain) { static_cast<Register*>(this)[RegisterFile::ScopeChain] = scopeChain; }
116
117 ALWAYS_INLINE void init(CodeBlock* codeBlock, Instruction* vPC, ScopeChainNode* scopeChain,
118 CallFrame* callerFrame, int returnValueRegister, int argc, JSObject* callee)
119 {
120 ASSERT(callerFrame); // Use noCaller() rather than 0 for the outer host call frame caller.
121
122 setCodeBlock(codeBlock);
123 setScopeChain(scopeChain);
124 setCallerFrame(callerFrame);
125 static_cast<Register*>(this)[RegisterFile::ReturnPC] = vPC; // This is either an Instruction* or a pointer into JIT generated code stored as an Instruction*.
126 static_cast<Register*>(this)[RegisterFile::ReturnValueRegister] = Register::withInt(i: returnValueRegister);
127 setArgumentCount(argc); // original argument count (for the sake of the "arguments" object)
128 setCallee(callee);
129 setCalleeArguments(JSValue());
130 }
131
132 // Read a register from the codeframe (or constant from the CodeBlock).
133 inline Register& r(int);
134
135 static CallFrame* noCaller() { return reinterpret_cast<CallFrame*>(HostCallFrameFlag); }
136 int returnValueRegister() const { return this[RegisterFile::ReturnValueRegister].i(); }
137
138 bool hasHostCallFrameFlag() const { return reinterpret_cast<intptr_t>(this) & HostCallFrameFlag; }
139 CallFrame* addHostCallFrameFlag() const { return reinterpret_cast<CallFrame*>(reinterpret_cast<intptr_t>(this) | HostCallFrameFlag); }
140 CallFrame* removeHostCallFrameFlag() { return reinterpret_cast<CallFrame*>(reinterpret_cast<intptr_t>(this) & ~HostCallFrameFlag); }
141
142 private:
143 void setArgumentCount(int count) { static_cast<Register*>(this)[RegisterFile::ArgumentCount] = Register::withInt(i: count); }
144 void setCallee(JSObject* callee) { static_cast<Register*>(this)[RegisterFile::Callee] = callee; }
145 void setCodeBlock(CodeBlock* codeBlock) { static_cast<Register*>(this)[RegisterFile::CodeBlock] = codeBlock; }
146
147 static const intptr_t HostCallFrameFlag = 1;
148
149 ExecState();
150 ~ExecState();
151 };
152
153} // namespace JSC
154
155#endif // CallFrame_h
156

source code of qtscript/src/3rdparty/javascriptcore/JavaScriptCore/interpreter/CallFrame.h