1 /**************************************************************************** 2 ** 3 ** Copyright (C) 2018 The Qt Company Ltd. 4 ** Contact: https://www.qt.io/licensing/ 5 ** 6 ** This file is part of the QtQml module of the Qt Toolkit. 7 ** 8 ** $QT_BEGIN_LICENSE:LGPL$ 9 ** Commercial License Usage 10 ** Licensees holding valid commercial Qt licenses may use this file in 11 ** accordance with the commercial license agreement provided with the 12 ** Software or, alternatively, in accordance with the terms contained in 13 ** a written agreement between you and The Qt Company. For licensing terms 14 ** and conditions see https://www.qt.io/terms-conditions. For further 15 ** information use the contact form at https://www.qt.io/contact-us. 16 ** 17 ** GNU Lesser General Public License Usage 18 ** Alternatively, this file may be used under the terms of the GNU Lesser 19 ** General Public License version 3 as published by the Free Software 20 ** Foundation and appearing in the file LICENSE.LGPL3 included in the 21 ** packaging of this file. Please review the following information to 22 ** ensure the GNU Lesser General Public License version 3 requirements 23 ** will be met: https://www.gnu.org/licenses/lgpl-3.0.html. 24 ** 25 ** GNU General Public License Usage 26 ** Alternatively, this file may be used under the terms of the GNU 27 ** General Public License version 2.0 or (at your option) the GNU General 28 ** Public license version 3 or any later version approved by the KDE Free 29 ** Qt Foundation. The licenses are as published by the Free Software 30 ** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3 31 ** included in the packaging of this file. Please review the following 32 ** information to ensure the GNU General Public License requirements will 33 ** be met: https://www.gnu.org/licenses/gpl-2.0.html and 34 ** https://www.gnu.org/licenses/gpl-3.0.html. 35 ** 36 ** $QT_END_LICENSE$ 37 ** 38 ****************************************************************************/ 39 #ifndef QV4STACKFRAME_H 40 #define QV4STACKFRAME_H 41 42 // 43 // W A R N I N G 44 // ------------- 45 // 46 // This file is not part of the Qt API. It exists purely as an 47 // implementation detail. This header file may change from version to 48 // version without notice, or even be removed. 49 // 50 // We mean it. 51 // 52 53 #include <private/qv4context_p.h> 54 #include <private/qv4enginebase_p.h> 55 #include <private/qv4calldata_p.h> 56 #include <private/qv4function_p.h> 57 58 QT_BEGIN_NAMESPACE 59 60 namespace QV4 { 61 62 struct Q_QML_EXPORT CppStackFrame { 63 EngineBase *engine; 64 Value *savedStackTop; 65 CppStackFrame *parent; 66 Function *v4Function; 67 CallData *jsFrame; 68 const Value *originalArguments; 69 int originalArgumentsCount; 70 int instructionPointer; 71 const char *yield; 72 const char *unwindHandler; 73 const char *unwindLabel; 74 int unwindLevel; 75 bool yieldIsIterator; 76 bool callerCanHandleTailCall; 77 bool pendingTailCall; 78 bool isTailCalling; 79 80 void init(EngineBase *engine, Function *v4Function, const Value *argv, int argc, bool callerCanHandleTailCall = false) { 81 this->engine = engine; 82 83 this->v4Function = v4Function; 84 originalArguments = argv; 85 originalArgumentsCount = argc; 86 instructionPointer = 0; 87 yield = nullptr; 88 unwindHandler = nullptr; 89 unwindLabel = nullptr; 90 unwindLevel = 0; 91 yieldIsIterator = false; 92 this->callerCanHandleTailCall = callerCanHandleTailCall; 93 pendingTailCall = false; 94 isTailCalling = false; 95 } 96 pushCppStackFrame97 void push() { 98 parent = engine->currentStackFrame; 99 engine->currentStackFrame = this; 100 savedStackTop = engine->jsStackTop; 101 } 102 popCppStackFrame103 void pop() { 104 engine->currentStackFrame = parent; 105 engine->jsStackTop = savedStackTop; 106 } 107 requiredJSStackFrameSizeCppStackFrame108 static uint requiredJSStackFrameSize(uint nRegisters) { 109 return CallData::HeaderSize() + nRegisters; 110 } requiredJSStackFrameSizeCppStackFrame111 static uint requiredJSStackFrameSize(Function *v4Function) { 112 return CallData::HeaderSize() + v4Function->compiledFunction->nRegisters; 113 } requiredJSStackFrameSizeCppStackFrame114 uint requiredJSStackFrameSize() const { 115 return requiredJSStackFrameSize(v4Function); 116 } 117 void setupJSFrame(Value *stackSpace, const Value &function, const Heap::ExecutionContext *scope, 118 const Value &thisObject, const Value &newTarget = Value::undefinedValue()) { 119 setupJSFrame(stackSpace, function, scope, thisObject, newTarget, 120 v4Function->compiledFunction->nFormals, v4Function->compiledFunction->nRegisters); 121 } setupJSFrameCppStackFrame122 void setupJSFrame(Value *stackSpace, const Value &function, const Heap::ExecutionContext *scope, 123 const Value &thisObject, const Value &newTarget, uint nFormals, uint nRegisters) 124 { 125 jsFrame = reinterpret_cast<CallData *>(stackSpace); 126 jsFrame->function = function; 127 jsFrame->context = scope->asReturnedValue(); 128 jsFrame->accumulator = Encode::undefined(); 129 jsFrame->thisObject = thisObject; 130 jsFrame->newTarget = newTarget; 131 132 uint argc = uint(originalArgumentsCount); 133 if (argc > nFormals) 134 argc = nFormals; 135 jsFrame->setArgc(argc); 136 137 memcpy(jsFrame->args, originalArguments, argc*sizeof(Value)); 138 Q_STATIC_ASSERT(Encode::undefined() == 0); 139 memset(jsFrame->args + argc, 0, (nRegisters - argc)*sizeof(Value)); 140 141 if (v4Function && v4Function->compiledFunction) { 142 const int firstDeadZoneRegister = v4Function->compiledFunction->firstTemporalDeadZoneRegister; 143 const int registerDeadZoneSize = v4Function->compiledFunction->sizeOfRegisterTemporalDeadZone; 144 145 const Value * tdzEnd = stackSpace + firstDeadZoneRegister + registerDeadZoneSize; 146 for (Value *v = stackSpace + firstDeadZoneRegister; v < tdzEnd; ++v) 147 *v = Value::emptyValue().asReturnedValue(); 148 } 149 } 150 151 QString source() const; 152 QString function() const; contextCppStackFrame153 inline QV4::ExecutionContext *context() const { 154 return static_cast<ExecutionContext *>(&jsFrame->context); 155 } 156 int lineNumber() const; 157 callContextCppStackFrame158 inline QV4::Heap::CallContext *callContext() const { 159 Heap::ExecutionContext *ctx = static_cast<ExecutionContext &>(jsFrame->context).d();\ 160 while (ctx->type != Heap::ExecutionContext::Type_CallContext) 161 ctx = ctx->outer; 162 return static_cast<Heap::CallContext *>(ctx); 163 } 164 ReturnedValue thisObject() const; 165 }; 166 167 } 168 169 QT_END_NAMESPACE 170 171 #endif 172