qtdeclarative/src/qml/jsruntime/qv4engine_p.h

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/****************************************************************************
**
** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
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** This file is part of the QtQml module of the Qt Toolkit.
**
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** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
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** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
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#ifndef QV4ENGINE_H
#define QV4ENGINE_H
#include "qv4global_p.h"
#include "private/qv4isel_p.h"
#include "qv4util_p.h"
#include "qv4context_p.h"
#include "qv4property_p.h"
#include <private/qintrusivelist_p.h>
namespace WTF {
class BumpPointerAllocator;
}
QT_BEGIN_NAMESPACE
class QV8Engine;
namespace QV4 {
namespace Debugging {
class Debugger;
} // namespace Debugging
}
namespace QV4 {
struct Function;
struct Object;
struct BooleanObject;
struct NumberObject;
struct StringObject;
struct ArrayObject;
struct DateObject;
struct FunctionObject;
struct BoundFunction;
struct RegExpObject;
struct ErrorObject;
struct ArgumentsObject;
struct ExecutionContext;
struct ExecutionEngine;
class MemoryManager;
class UnwindHelper;
class ExecutableAllocator;
struct ObjectPrototype;
struct StringPrototype;
struct NumberPrototype;
struct BooleanPrototype;
struct ArrayPrototype;
struct FunctionPrototype;
struct DatePrototype;
struct RegExpPrototype;
struct ErrorPrototype;
struct EvalErrorPrototype;
struct RangeErrorPrototype;
struct ReferenceErrorPrototype;
struct SyntaxErrorPrototype;
struct TypeErrorPrototype;
struct URIErrorPrototype;
struct VariantPrototype;
struct SequencePrototype;
struct EvalFunction;
struct IdentifierTable;
struct InternalClass;
class MultiplyWrappedQObjectMap;
class RegExp;
class RegExpCache;
struct QmlExtensions;
struct Q_QML_EXPORT ExecutionEngine
{
MemoryManager *memoryManager;
ExecutableAllocator *executableAllocator;
Fix exception handling not working reliably on x86/x86-64 Linux (Part 2) The registration of the unwind tables is done through the interposition of the _Unwind_Find_FDE symbol from libgcc. Unfortunately that interposition breaks when libgcc happens to come first in the linker scope. As it turns out, the order is not for us to control, therefore the interposition may not always work and our JIT generated functions may not get their unwind information found at exception throwing time. That results in the program aborting with an uncaught exception. The proposed solution of replacing the interposition approach is two-fold: (1) Go back to calling __register_frame explicitly, but only for functions that exception _may_ pass through. In addition the performance of scalability of the objects registered with __register_frame is a known issue upstream, as the LLVM JIT also triggers the issue. It is being tracked at http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56460 (2) Instead of registering one FDE per function, we can theoretically register one FDE for _all_ JIT generate functions, because they all use the same stack layout that has exactly the same unwinding requirements from any function call site. Since we can't guarantee the presence of all JIT generated code within the same contiguous memory area, we can at least do it per executable memory allocation chunk (page size). One chunk can contain many functions. This patch implements part (2) by moving the per-function unwind info straight to into the executable memory chunk and registering the entire chunk (page) with libgcc. This also separates the regexp JIT executable memory from regular functions, because only for the memory of the latter we need to register unwind info. Change-Id: Ic4d1978686463c6d319436c9083e4d7cf0409829 Reviewed-by: Lars Knoll <lars.knoll@digia.com>
2013-05-12 10:07:15 +00:00
ExecutableAllocator *regExpAllocator;
QScopedPointer<QQmlJS::EvalISelFactory> iselFactory;
ExecutionContext *current;
GlobalContext *rootContext;
WTF::BumpPointerAllocator *bumperPointerAllocator; // Used by Yarr Regex engine.
IdentifierTable *identifierTable;
QV4::Debugging::Debugger *debugger;
Object *globalObject;
Function *globalCode;
QV8Engine *v8Engine;
Value objectCtor;
Value stringCtor;
Value numberCtor;
Value booleanCtor;
Value arrayCtor;
Value functionCtor;
Value dateCtor;
Value regExpCtor;
Value errorCtor;
Value evalErrorCtor;
Value rangeErrorCtor;
Value referenceErrorCtor;
Value syntaxErrorCtor;
Value typeErrorCtor;
Value uRIErrorCtor;
ObjectPrototype *objectPrototype;
StringPrototype *stringPrototype;
NumberPrototype *numberPrototype;
BooleanPrototype *booleanPrototype;
ArrayPrototype *arrayPrototype;
FunctionPrototype *functionPrototype;
DatePrototype *datePrototype;
RegExpPrototype *regExpPrototype;
ErrorPrototype *errorPrototype;
EvalErrorPrototype *evalErrorPrototype;
RangeErrorPrototype *rangeErrorPrototype;
ReferenceErrorPrototype *referenceErrorPrototype;
SyntaxErrorPrototype *syntaxErrorPrototype;
TypeErrorPrototype *typeErrorPrototype;
URIErrorPrototype *uRIErrorPrototype;
VariantPrototype *variantPrototype;
SequencePrototype *sequencePrototype;
QQmlJS::MemoryPool classPool;
InternalClass *emptyClass;
InternalClass *arrayClass;
EvalFunction *evalFunction;
QVector<Property> argumentsAccessors;
String *id_undefined;
String *id_null;
String *id_true;
String *id_false;
String *id_boolean;
String *id_number;
String *id_string;
String *id_object;
String *id_function;
String *id_length;
String *id_prototype;
String *id_constructor;
String *id_arguments;
String *id_caller;
String *id_this;
String *id___proto__;
String *id_enumerable;
String *id_configurable;
String *id_writable;
String *id_value;
String *id_get;
String *id_set;
String *id_eval;
String *id_uintMax;
String *id_name;
mutable QVector<Function *> functions;
mutable bool functionsNeedSort;
quint32 m_engineId;
RegExpCache *regExpCache;
// Scarce resources are "exceptionally high cost" QVariant types where allowing the
// normal JavaScript GC to clean them up is likely to lead to out-of-memory or other
// out-of-resource situations. When such a resource is passed into JavaScript we
// add it to the scarceResources list and it is destroyed when we return from the
// JavaScript execution that created it. The user can prevent this behavior by
// calling preserve() on the object which removes it from this scarceResource list.
class ScarceResourceData {
public:
ScarceResourceData(const QVariant &data) : data(data) {}
QVariant data;
QIntrusiveListNode node;
};
QIntrusiveList<ScarceResourceData, &ScarceResourceData::node> scarceResources;
// Normally the JS wrappers for QObjects are stored in the QQmlData/QObjectPrivate,
// but any time a QObject is wrapped a second time in another engine, we have to do
// bookkeeping.
MultiplyWrappedQObjectMap *m_multiplyWrappedQObjects;
ExecutionEngine(QQmlJS::EvalISelFactory *iselFactory = 0);
~ExecutionEngine();
void enableDebugger();
WithContext *newWithContext(Object *with);
CatchContext *newCatchContext(String* exceptionVarName, const QV4::Value &exceptionValue);
CallContext *newCallContext(FunctionObject *f, const QV4::Value &thisObject, QV4::Value *args, int argc);
CallContext *newCallContext(void *stackSpace, FunctionObject *f, const QV4::Value &thisObject, QV4::Value *args, int argc);
CallContext *newQmlContext(FunctionObject *f, Object *qml);
ExecutionContext *pushGlobalContext();
void pushContext(SimpleCallContext *context);
ExecutionContext *popContext();
Function *newFunction(const QString &name);
FunctionObject *newBuiltinFunction(ExecutionContext *scope, String *name, Value (*code)(SimpleCallContext *));
FunctionObject *newScriptFunction(ExecutionContext *scope, Function *function);
BoundFunction *newBoundFunction(ExecutionContext *scope, FunctionObject *target, Value boundThis, const QVector<Value> &boundArgs);
Object *newObject();
Object *newObject(InternalClass *internalClass);
String *newString(const QString &s);
String *newIdentifier(const QString &text);
Object *newStringObject(const Value &value);
Object *newNumberObject(const Value &value);
Object *newBooleanObject(const Value &value);
ArrayObject *newArrayObject(int count = 0);
ArrayObject *newArrayObject(const QStringList &list);
DateObject *newDateObject(const Value &value);
DateObject *newDateObject(const QDateTime &dt);
RegExpObject *newRegExpObject(const QString &pattern, int flags);
RegExpObject *newRegExpObject(RegExp* re, bool global);
RegExpObject *newRegExpObject(const QRegExp &re);
Object *newErrorObject(const Value &value);
Object *newSyntaxErrorObject(ExecutionContext *ctx, DiagnosticMessage *message);
Object *newSyntaxErrorObject(const QString &message);
Object *newReferenceErrorObject(const QString &message);
Object *newReferenceErrorObject(const QString &message, const QString &fileName, int lineNumber);
Object *newTypeErrorObject(const QString &message);
Object *newRangeErrorObject(const QString &message);
Object *newURIErrorObject(Value message);
Object *newVariantObject(const QVariant &v);
Object *newForEachIteratorObject(ExecutionContext *ctx, Object *o);
Object *qmlContextObject() const;
struct StackFrame {
QString source;
QString function;
int line;
int column;
};
typedef QVector<StackFrame> StackTrace;
StackTrace stackTrace(int frameLimit = -1) const;
StackFrame currentStackFrame() const;
QUrl resolvedUrl(const QString &file);
void requireArgumentsAccessors(int n);
void markObjects();
void initRootContext();
InternalClass *newClass(const InternalClass &other);
Function *functionForProgramCounter(quintptr pc) const;
QmlExtensions *qmlExtensions();
private:
QmlExtensions *m_qmlExtensions;
};
inline void ExecutionEngine::pushContext(SimpleCallContext *context)
{
context->parent = current;
current = context;
current->currentEvalCode = 0;
}
inline ExecutionContext *ExecutionEngine::popContext()
{
CallContext *c = current->asCallContext();
if (c && !c->needsOwnArguments()) {
c->arguments = 0;
c->argumentCount = 0;
}
current = current->parent;
return current;
}
} // namespace QV4
QT_END_NAMESPACE
#endif // QV4ENGINE_H