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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 | |
97 | void push() { |
98 | parent = engine->currentStackFrame; |
99 | engine->currentStackFrame = this; |
100 | savedStackTop = engine->jsStackTop; |
101 | } |
102 | |
103 | void pop() { |
104 | engine->currentStackFrame = parent; |
105 | engine->jsStackTop = savedStackTop; |
106 | } |
107 | |
108 | static uint requiredJSStackFrameSize(uint nRegisters) { |
109 | return CallData::HeaderSize() + nRegisters; |
110 | } |
111 | static uint requiredJSStackFrameSize(Function *v4Function) { |
112 | return CallData::HeaderSize() + v4Function->compiledFunction->nRegisters; |
113 | } |
114 | 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 | nFormals: v4Function->compiledFunction->nFormals, nRegisters: v4Function->compiledFunction->nRegisters); |
121 | } |
122 | 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(dest: jsFrame->args, src: originalArguments, n: argc*sizeof(Value)); |
138 | Q_STATIC_ASSERT(Encode::undefined() == 0); |
139 | memset(s: jsFrame->args + argc, c: 0, n: (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; |
153 | inline QV4::ExecutionContext *context() const { |
154 | return static_cast<ExecutionContext *>(&jsFrame->context); |
155 | } |
156 | int lineNumber() const; |
157 | |
158 | 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 | |