2 * Copyright (C) 1999-2001 Harri Porten (porten@kde.org)
3 * Copyright (C) 2001 Peter Kelly (pmk@post.com)
4 * Copyright (C) 2003, 2007, 2008, 2011 Apple Inc. All rights reserved.
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.
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.
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.
26 #include "JSGlobalData.h"
27 #include "MacroAssemblerCodeRef.h"
28 #include "RegisterFile.h"
37 // Represents the current state of script execution.
38 // Passed as the first argument to most functions.
39 class ExecState : private Register {
41 JSValue calleeAsValue() const { return this[RegisterFile::Callee].jsValue(); }
42 JSObject* callee() const { return this[RegisterFile::Callee].function(); }
43 CodeBlock* codeBlock() const { return this[RegisterFile::CodeBlock].Register::codeBlock(); }
44 ScopeChainNode* scopeChain() const
46 ASSERT(this[RegisterFile::ScopeChain].Register::scopeChain());
47 return this[RegisterFile::ScopeChain].Register::scopeChain();
50 // Global object in which execution began.
51 JSGlobalObject* dynamicGlobalObject();
53 // Global object in which the currently executing code was defined.
54 // Differs from dynamicGlobalObject() during function calls across web browser frames.
55 inline JSGlobalObject* lexicalGlobalObject() const;
57 // Differs from lexicalGlobalObject because this will have DOM window shell rather than
58 // the actual DOM window, which can't be "this" for security reasons.
59 inline JSObject* globalThisValue() const;
61 inline JSGlobalData& globalData() const;
63 // Convenience functions for access to global data.
64 // It takes a few memory references to get from a call frame to the global data
65 // pointer, so these are inefficient, and should be used sparingly in new code.
66 // But they're used in many places in legacy code, so they're not going away any time soon.
68 void clearException() { globalData().exception = JSValue(); }
69 JSValue exception() const { return globalData().exception; }
70 bool hadException() const { return globalData().exception; }
72 const CommonIdentifiers& propertyNames() const { return *globalData().propertyNames; }
73 const MarkedArgumentBuffer& emptyList() const { return *globalData().emptyList; }
74 Interpreter* interpreter() { return globalData().interpreter; }
75 Heap* heap() { return &globalData().heap; }
79 static const HashTable* arrayConstructorTable(CallFrame* callFrame) { return callFrame->globalData().arrayConstructorTable; }
80 static const HashTable* arrayPrototypeTable(CallFrame* callFrame) { return callFrame->globalData().arrayPrototypeTable; }
81 static const HashTable* booleanPrototypeTable(CallFrame* callFrame) { return callFrame->globalData().booleanPrototypeTable; }
82 static const HashTable* dateTable(CallFrame* callFrame) { return callFrame->globalData().dateTable; }
83 static const HashTable* dateConstructorTable(CallFrame* callFrame) { return callFrame->globalData().dateConstructorTable; }
84 static const HashTable* errorPrototypeTable(CallFrame* callFrame) { return callFrame->globalData().errorPrototypeTable; }
85 static const HashTable* globalObjectTable(CallFrame* callFrame) { return callFrame->globalData().globalObjectTable; }
86 static const HashTable* jsonTable(CallFrame* callFrame) { return callFrame->globalData().jsonTable; }
87 static const HashTable* mathTable(CallFrame* callFrame) { return callFrame->globalData().mathTable; }
88 static const HashTable* numberConstructorTable(CallFrame* callFrame) { return callFrame->globalData().numberConstructorTable; }
89 static const HashTable* numberPrototypeTable(CallFrame* callFrame) { return callFrame->globalData().numberPrototypeTable; }
90 static const HashTable* objectConstructorTable(CallFrame* callFrame) { return callFrame->globalData().objectConstructorTable; }
91 static const HashTable* objectPrototypeTable(CallFrame* callFrame) { return callFrame->globalData().objectPrototypeTable; }
92 static const HashTable* regExpTable(CallFrame* callFrame) { return callFrame->globalData().regExpTable; }
93 static const HashTable* regExpConstructorTable(CallFrame* callFrame) { return callFrame->globalData().regExpConstructorTable; }
94 static const HashTable* regExpPrototypeTable(CallFrame* callFrame) { return callFrame->globalData().regExpPrototypeTable; }
95 static const HashTable* stringTable(CallFrame* callFrame) { return callFrame->globalData().stringTable; }
96 static const HashTable* stringConstructorTable(CallFrame* callFrame) { return callFrame->globalData().stringConstructorTable; }
98 static CallFrame* create(Register* callFrameBase) { return static_cast<CallFrame*>(callFrameBase); }
99 Register* registers() { return this; }
101 CallFrame& operator=(const Register& r) { *static_cast<Register*>(this) = r; return *this; }
103 CallFrame* callerFrame() const { return this[RegisterFile::CallerFrame].callFrame(); }
105 ReturnAddressPtr returnPC() const { return ReturnAddressPtr(this[RegisterFile::ReturnPC].vPC()); }
108 InlineCallFrame* inlineCallFrame() const { return this[RegisterFile::ReturnPC].asInlineCallFrame(); }
110 // This will never be called if !ENABLE(DFG_JIT) since all calls should be guarded by
111 // isInlineCallFrame(). But to make it easier to write code without having a bunch of
112 // #if's, we make a dummy implementation available anyway.
113 InlineCallFrame* inlineCallFrame() const
115 ASSERT_NOT_REACHED();
119 #if ENABLE(INTERPRETER)
120 Instruction* returnVPC() const { return this[RegisterFile::ReturnPC].vPC(); }
123 void setCallerFrame(CallFrame* callerFrame) { static_cast<Register*>(this)[RegisterFile::CallerFrame] = callerFrame; }
124 void setScopeChain(ScopeChainNode* scopeChain) { static_cast<Register*>(this)[RegisterFile::ScopeChain] = scopeChain; }
126 ALWAYS_INLINE void init(CodeBlock* codeBlock, Instruction* vPC, ScopeChainNode* scopeChain,
127 CallFrame* callerFrame, int argc, JSObject* callee)
129 ASSERT(callerFrame); // Use noCaller() rather than 0 for the outer host call frame caller.
130 ASSERT(callerFrame == noCaller() || callerFrame->removeHostCallFrameFlag()->registerFile()->end() >= this);
132 setCodeBlock(codeBlock);
133 setScopeChain(scopeChain);
134 setCallerFrame(callerFrame);
135 setReturnPC(vPC); // This is either an Instruction* or a pointer into JIT generated code stored as an Instruction*.
136 setArgumentCountIncludingThis(argc); // original argument count (for the sake of the "arguments" object)
140 // Read a register from the codeframe (or constant from the CodeBlock).
141 inline Register& r(int);
142 // Read a register for a non-constant
143 inline Register& uncheckedR(int);
145 // Access to arguments.
146 int hostThisRegister() { return -RegisterFile::CallFrameHeaderSize - argumentCountIncludingThis(); }
147 JSValue hostThisValue() { return this[hostThisRegister()].jsValue(); }
148 size_t argumentCount() const { return argumentCountIncludingThis() - 1; }
149 size_t argumentCountIncludingThis() const { return this[RegisterFile::ArgumentCount].i(); }
150 JSValue argument(int argumentNumber)
152 int argumentIndex = -RegisterFile::CallFrameHeaderSize - this[RegisterFile::ArgumentCount].i() + argumentNumber + 1;
153 if (argumentIndex >= -RegisterFile::CallFrameHeaderSize)
154 return jsUndefined();
155 return this[argumentIndex].jsValue();
158 static CallFrame* noCaller() { return reinterpret_cast<CallFrame*>(HostCallFrameFlag); }
160 bool hasHostCallFrameFlag() const { return reinterpret_cast<intptr_t>(this) & HostCallFrameFlag; }
161 CallFrame* addHostCallFrameFlag() const { return reinterpret_cast<CallFrame*>(reinterpret_cast<intptr_t>(this) | HostCallFrameFlag); }
162 CallFrame* removeHostCallFrameFlag() { return reinterpret_cast<CallFrame*>(reinterpret_cast<intptr_t>(this) & ~HostCallFrameFlag); }
164 void setArgumentCountIncludingThis(int count) { static_cast<Register*>(this)[RegisterFile::ArgumentCount] = Register::withInt(count); }
165 void setCallee(JSObject* callee) { static_cast<Register*>(this)[RegisterFile::Callee] = Register::withCallee(callee); }
166 void setCodeBlock(CodeBlock* codeBlock) { static_cast<Register*>(this)[RegisterFile::CodeBlock] = codeBlock; }
167 void setReturnPC(void* value) { static_cast<Register*>(this)[RegisterFile::ReturnPC] = (Instruction*)value; }
170 bool isInlineCallFrame();
172 void setInlineCallFrame(InlineCallFrame* inlineCallFrame) { static_cast<Register*>(this)[RegisterFile::ReturnPC] = inlineCallFrame; }
174 // Call this to get the semantically correct JS CallFrame*. This resolves issues
175 // surrounding inlining and the HostCallFrameFlag stuff.
176 CallFrame* trueCallerFrame();
178 bool isInlineCallFrame() { return false; }
180 CallFrame* trueCallerFrame() { return callerFrame()->removeHostCallFrameFlag(); }
183 #if ENABLE(TIZEN_JS_EXT_API)
184 int getExecutionState() { return globalData().getExecutionState(); }
185 void setExecutionState(bool b) { globalData().setExecutionState(b); }
189 static const intptr_t HostCallFrameFlag = 1;
191 RegisterFile* registerFile();
194 bool isInlineCallFrameSlow();
202 #endif // CallFrame_h