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39#ifndef QV4ENGINEBASE_P_H
40#define QV4ENGINEBASE_P_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/qv4global_p.h>
54#include <private/qv4runtimeapi_p.h>
55
56QT_BEGIN_NAMESPACE
57
58namespace QV4 {
59
60struct CppStackFrame;
61
62// Base class for the execution engine
63
64#if defined(Q_CC_MSVC) || defined(Q_CC_GNU)
65#pragma pack(push, 1)
66#endif
67struct Q_QML_EXPORT EngineBase {
68
69 CppStackFrame *currentStackFrame = nullptr;
70
71 Value *jsStackTop = nullptr;
72
73 // The JIT expects hasException and isInterrupted to be in the same 32bit word in memory.
74 quint8 hasException = false;
75 // isInterrupted is expected to be set from a different thread
76#if defined(Q_ATOMIC_INT8_IS_SUPPORTED)
77 QAtomicInteger<quint8> isInterrupted = false;
78 quint16 unused = 0;
79#elif defined(Q_ATOMIC_INT16_IS_SUPPORTED)
80 quint8 unused = 0;
81 QAtomicInteger<quint16> isInterrupted = false;
82#else
83# error V4 needs either 8bit or 16bit atomics.
84#endif
85
86 quint8 isExecutingInRegExpJIT = false;
87 quint8 padding[3];
88 MemoryManager *memoryManager = nullptr;
89 Runtime runtime;
90
91 qint32 callDepth = 0;
92 Value *jsStackLimit = nullptr;
93 Value *jsStackBase = nullptr;
94
95 IdentifierTable *identifierTable = nullptr;
96 Object *globalObject = nullptr;
97
98 // Exception handling
99 Value *exceptionValue = nullptr;
100
101 enum InternalClassType {
102 Class_Empty,
103 Class_String,
104 Class_MemberData,
105 Class_SimpleArrayData,
106 Class_SparseArrayData,
107 Class_ExecutionContext,
108 Class_CallContext,
109 Class_QmlContext,
110 Class_Object,
111 Class_ArrayObject,
112 Class_FunctionObject,
113 Class_ArrowFunction,
114 Class_GeneratorFunction,
115 Class_GeneratorObject,
116 Class_StringObject,
117 Class_SymbolObject,
118 Class_ScriptFunction,
119 Class_ConstructorFunction,
120 Class_MemberFunction,
121 Class_MemberGeneratorFunction,
122 Class_ObjectProto,
123 Class_RegExp,
124 Class_RegExpObject,
125 Class_RegExpExecArray,
126 Class_ArgumentsObject,
127 Class_StrictArgumentsObject,
128 Class_ErrorObject,
129 Class_ErrorObjectWithMessage,
130 Class_ErrorProto,
131 Class_QmlContextWrapper,
132 Class_ProxyObject,
133 Class_ProxyFunctionObject,
134 Class_Symbol,
135 NClasses
136 };
137 Heap::InternalClass *classes[NClasses];
138 Heap::InternalClass *internalClasses(InternalClassType icType) { return classes[icType]; }
139};
140#if defined(Q_CC_MSVC) || defined(Q_CC_GNU)
141#pragma pack(pop)
142#endif
143
144Q_STATIC_ASSERT(std::is_standard_layout<EngineBase>::value);
145Q_STATIC_ASSERT(offsetof(EngineBase, currentStackFrame) == 0);
146Q_STATIC_ASSERT(offsetof(EngineBase, jsStackTop) == offsetof(EngineBase, currentStackFrame) + QT_POINTER_SIZE);
147Q_STATIC_ASSERT(offsetof(EngineBase, hasException) == offsetof(EngineBase, jsStackTop) + QT_POINTER_SIZE);
148Q_STATIC_ASSERT(offsetof(EngineBase, memoryManager) == offsetof(EngineBase, hasException) + 8);
149Q_STATIC_ASSERT(offsetof(EngineBase, runtime) == offsetof(EngineBase, memoryManager) + QT_POINTER_SIZE);
150Q_STATIC_ASSERT(offsetof(EngineBase, isInterrupted) + sizeof(EngineBase::isInterrupted) <= offsetof(EngineBase, hasException) + 4);
151
152}
153
154QT_END_NAMESPACE
155
156#endif
157