C++ JSFunction::isInterpreted方法代码示例

bool
CreateThis(JSContext *cx, HandleObject callee, MutableHandleValue rval)
{
    rval.set(MagicValue(JS_IS_CONSTRUCTING));

    if (callee->isFunction()) {
        JSFunction *fun = callee->toFunction();
        if (fun->isInterpreted())
            rval.set(ObjectValue(*js_CreateThisForFunction(cx, callee, false)));
    }

    return true;
}

bool
MarkInnerAndOuterFunctions(JSContext *cx, JSScript* script_)
{
    Rooted<JSScript*> script(cx, script_);

    Vector<JSScript *, 16> worklist(cx);
    if (!worklist.append(script.reference()))
        return false;

    while (worklist.length()) {
        JSScript *outer = worklist.back();
        worklist.popBack();

        /*
         * If outer has an extensible scope, its slots may be resized which
         * will invalidate nesting->varArray/argArray.
         */
        if (outer->funHasExtensibleScope)
            continue;

        if (outer->hasObjects()) {
            ObjectArray *arr = outer->objects();

            /*
             * If this is an eval script, don't treat the saved caller function
             * stored in the first object slot as an inner function.
             */
            size_t start = outer->savedCallerFun ? 1 : 0;

            for (size_t i = start; i < arr->length; i++) {
                JSObject *obj = arr->vector[i];
                if (!obj->isFunction())
                    continue;
                JSFunction *fun = obj->toFunction();
                JS_ASSERT(fun->isInterpreted());
                JSScript *inner = fun->script();
                if (outer->function() && outer->function()->isHeavyweight()) {
                    outer->isOuterFunction = true;
                    inner->isInnerFunction = true;
                }
                if (!inner->hasObjects())
                    continue;
                if (!worklist.append(inner))
                    return false;
            }
        }
    }

    return true;
}

static JSObject *
ResolveInterpretedFunctionPrototype(JSContext *cx, HandleObject obj)
{
#ifdef DEBUG
    JSFunction *fun = obj->toFunction();
    JS_ASSERT(fun->isInterpreted());
    JS_ASSERT(!fun->isFunctionPrototype());
#endif

    /*
     * Assert that fun is not a compiler-created function object, which
     * must never leak to script or embedding code and then be mutated.
     * Also assert that obj is not bound, per the ES5 15.3.4.5 ref above.
     */
    JS_ASSERT(!IsInternalFunctionObject(obj));
    JS_ASSERT(!obj->isBoundFunction());

    /*
     * Make the prototype object an instance of Object with the same parent
     * as the function object itself.
     */
    JSObject *objProto = obj->global().getOrCreateObjectPrototype(cx);
    if (!objProto)
        return NULL;
    RootedObject proto(cx, NewObjectWithGivenProto(cx, &ObjectClass, objProto, NULL));
    if (!proto || !proto->setSingletonType(cx))
        return NULL;

    /*
     * Per ES5 15.3.5.2 a user-defined function's .prototype property is
     * initially non-configurable, non-enumerable, and writable.  Per ES5 13.2
     * the prototype's .constructor property is configurable, non-enumerable,
     * and writable.
     */
    RootedValue protoVal(cx, ObjectValue(*proto));
    RootedValue objVal(cx, ObjectValue(*obj));
    if (!obj->defineProperty(cx, cx->runtime->atomState.classPrototypeAtom,
                             protoVal, JS_PropertyStub, JS_StrictPropertyStub,
                             JSPROP_PERMANENT) ||
        !proto->defineProperty(cx, cx->runtime->atomState.constructorAtom,
                               objVal, JS_PropertyStub, JS_StrictPropertyStub, 0))
    {
       return NULL;
    }

    return proto;
}

bool
CreateThis(JSContext *cx, HandleObject callee, MutableHandleValue rval)
{
    rval.set(MagicValue(JS_IS_CONSTRUCTING));

    if (callee->isFunction()) {
        JSFunction *fun = callee->toFunction();
        if (fun->isInterpreted()) {
            JSScript *script = fun->getOrCreateScript(cx);
            if (!script || !script->ensureHasTypes(cx))
                return false;
            rval.set(ObjectValue(*CreateThisForFunction(cx, callee, false)));
        }
    }

    return true;
}

bool
MarkInnerAndOuterFunctions(JSContext *cx, JSScript* script)
{
    Root<JSScript*> root(cx, &script);

    Vector<JSScript *, 16> worklist(cx);
    if (!worklist.append(script))
        return false;

    while (worklist.length()) {
        JSScript *outer = worklist.back();
        worklist.popBack();

        if (outer->hasObjects()) {
            ObjectArray *arr = outer->objects();

            /*
             * If this is an eval script, don't treat the saved caller function
             * stored in the first object slot as an inner function.
             */
            size_t start = outer->savedCallerFun ? 1 : 0;

            for (size_t i = start; i < arr->length; i++) {
                JSObject *obj = arr->vector[i];
                if (!obj->isFunction())
                    continue;
                JSFunction *fun = obj->toFunction();
                JS_ASSERT(fun->isInterpreted());
                JSScript *inner = fun->script();
                if (outer->function() && outer->function()->isHeavyweight()) {
                    outer->isOuterFunction = true;
                    inner->isInnerFunction = true;
                }
                if (!inner->hasObjects())
                    continue;
                if (!worklist.append(inner))
                    return false;
            }
        }
    }

    return true;
}

/*
 * This helper function brings the ContextStack to the top of the thread stack
 * (so that it can be extended to push a frame and/or arguments) by potentially
 * pushing a StackSegment. The 'pushedSeg' outparam indicates whether such a
 * segment was pushed (and hence whether the caller needs to call popSegment).
 *
 * Additionally, to minimize calls to ensureSpace, ensureOnTop ensures that
 * there is space for nvars slots on top of the stack.
 */
Value *
ContextStack::ensureOnTop(JSContext *cx, MaybeReportError report, unsigned nvars,
                          MaybeExtend extend, bool *pushedSeg, JSCompartment *dest)
{
    Value *firstUnused = space().firstUnused();

#ifdef JS_METHODJIT
    /*
     * The only calls made by inlined methodjit frames can be to other JIT
     * frames associated with the same VMFrame. If we try to Invoke(),
     * Execute() or so forth, any topmost inline frame will need to be
     * expanded (along with other inline frames in the compartment).
     * To avoid pathological behavior here, make sure to mark any topmost
     * function as uninlineable, which will expand inline frames if there are
     * any and prevent the function from being inlined in the future.
     */
    if (FrameRegs *regs = cx->maybeRegs()) {
        JSFunction *fun = NULL;
        if (InlinedSite *site = regs->inlined()) {
            mjit::JITChunk *chunk = regs->fp()->jit()->chunk(regs->pc);
            fun = chunk->inlineFrames()[site->inlineIndex].fun;
        } else {
            StackFrame *fp = regs->fp();
            if (fp->isFunctionFrame()) {
                JSFunction *f = fp->fun();
                if (f->isInterpreted())
                    fun = f;
            }
        }

        if (fun) {
            fun->script()->uninlineable = true;
            types::MarkTypeObjectFlags(cx, fun, types::OBJECT_FLAG_UNINLINEABLE);
        }
    }
    JS_ASSERT_IF(cx->hasfp(), !cx->regs().inlined());
#endif

    if (onTop() && extend) {
        if (!space().ensureSpace(cx, report, firstUnused, nvars, dest))
            return NULL;
        return firstUnused;
    }

    if (!space().ensureSpace(cx, report, firstUnused, VALUES_PER_STACK_SEGMENT + nvars, dest))
        return NULL;

    FrameRegs *regs;
    CallArgsList *calls;
    if (seg_ && extend) {
        regs = seg_->maybeRegs();
        calls = seg_->maybeCalls();
    } else {
        regs = NULL;
        calls = NULL;
    }

    seg_ = new(firstUnused) StackSegment(seg_, space().seg_, regs, calls);
    space().seg_ = seg_;
    *pushedSeg = true;
    return seg_->slotsBegin();
}

static JSBool
fun_getProperty(JSContext *cx, HandleObject obj_, HandleId id, Value *vp)
{
    JSObject *obj = obj_;
    while (!obj->isFunction()) {
        obj = obj->getProto();
        if (!obj)
            return true;
    }
    JSFunction *fun = obj->toFunction();

    /*
     * Mark the function's script as uninlineable, to expand any of its
     * frames on the stack before we go looking for them. This allows the
     * below walk to only check each explicit frame rather than needing to
     * check any calls that were inlined.
     */
    if (fun->isInterpreted()) {
        fun->script()->uninlineable = true;
        MarkTypeObjectFlags(cx, fun, OBJECT_FLAG_UNINLINEABLE);
    }

    /* Set to early to null in case of error */
    vp->setNull();

    /* Find fun's top-most activation record. */
    StackIter iter(cx);
    for (; !iter.done(); ++iter) {
        if (!iter.isFunctionFrame() || iter.isEvalFrame())
            continue;
        if (iter.callee() == fun)
            break;
    }
    if (iter.done())
        return true;

    StackFrame *fp = iter.fp();

    if (JSID_IS_ATOM(id, cx->runtime->atomState.argumentsAtom)) {
        if (fun->hasRest()) {
            JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL, JSMSG_FUNCTION_ARGUMENTS_AND_REST);
            return false;
        }
        /* Warn if strict about f.arguments or equivalent unqualified uses. */
        if (!JS_ReportErrorFlagsAndNumber(cx, JSREPORT_WARNING | JSREPORT_STRICT, js_GetErrorMessage,
                                          NULL, JSMSG_DEPRECATED_USAGE, js_arguments_str)) {
            return false;
        }

        ArgumentsObject *argsobj = ArgumentsObject::createUnexpected(cx, fp);
        if (!argsobj)
            return false;

        *vp = ObjectValue(*argsobj);
        return true;
    }

#ifdef JS_METHODJIT
    if (JSID_IS_ATOM(id, cx->runtime->atomState.callerAtom) && fp && fp->prev()) {
        /*
         * If the frame was called from within an inlined frame, mark the
         * innermost function as uninlineable to expand its frame and allow us
         * to recover its callee object.
         */
        JSInlinedSite *inlined;
        jsbytecode *prevpc = fp->prev()->pcQuadratic(cx->stack, fp, &inlined);
        if (inlined) {
            mjit::JITChunk *chunk = fp->prev()->jit()->chunk(prevpc);
            JSFunction *fun = chunk->inlineFrames()[inlined->inlineIndex].fun;
            fun->script()->uninlineable = true;
            MarkTypeObjectFlags(cx, fun, OBJECT_FLAG_UNINLINEABLE);
        }
    }
#endif

    if (JSID_IS_ATOM(id, cx->runtime->atomState.callerAtom)) {
        StackIter prev(iter);
        do {
            ++prev;
        } while (!prev.done() && prev.isImplicitNativeCall());

        if (prev.done() || !prev.isFunctionFrame()) {
            JS_ASSERT(vp->isNull());
            return true;
        }
        *vp = prev.calleev();

        /* Censor the caller if it is from another compartment. */
        JSObject &caller = vp->toObject();
        if (caller.compartment() != cx->compartment) {
            vp->setNull();
        } else if (caller.isFunction()) {
            JSFunction *callerFun = caller.toFunction();
            if (callerFun->isInterpreted() && callerFun->inStrictMode()) {
                JS_ReportErrorFlagsAndNumber(cx, JSREPORT_ERROR, js_GetErrorMessage, NULL,
                                             JSMSG_CALLER_IS_STRICT);
                return false;
            }
        }

//.........这里部分代码省略.........

bool
js::XDRInterpretedFunction(XDRState<mode> *xdr, JSObject **objp, JSScript *parentScript)
{
    /* NB: Keep this in sync with CloneInterpretedFunction. */
    JSFunction *fun;
    JSAtom *atom;
    uint32_t firstword;           /* flag telling whether fun->atom is non-null,
                                   plus for fun->u.i.skipmin, fun->u.i.wrapper,
                                   and 14 bits reserved for future use */
    uint32_t flagsword;           /* word for argument count and fun->flags */

    JSContext *cx = xdr->cx();
    JSScript *script;
    if (mode == XDR_ENCODE) {
        fun = (*objp)->toFunction();
        if (!fun->isInterpreted()) {
            JSAutoByteString funNameBytes;
            if (const char *name = GetFunctionNameBytes(cx, fun, &funNameBytes)) {
                JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL, JSMSG_NOT_SCRIPTED_FUNCTION,
                                     name);
            }
            return false;
        }
        firstword = !!fun->atom;
        flagsword = (fun->nargs << 16) | fun->flags;
        atom = fun->atom;
        script = fun->script();
    } else {
        RootedObject parent(cx, NULL);
        fun = js_NewFunction(cx, NULL, NULL, 0, JSFUN_INTERPRETED, parent, NULL);
        if (!fun)
            return false;
        if (!fun->clearParent(cx))
            return false;
        if (!fun->clearType(cx))
            return false;
        atom = NULL;
        script = NULL;
    }

    if (!xdr->codeUint32(&firstword))
        return false;
    if ((firstword & 1U) && !XDRAtom(xdr, &atom))
        return false;
    if (!xdr->codeUint32(&flagsword))
        return false;

    if (!XDRScript(xdr, &script, parentScript))
        return false;

    if (mode == XDR_DECODE) {
        fun->nargs = flagsword >> 16;
        JS_ASSERT((flagsword & JSFUN_KINDMASK) >= JSFUN_INTERPRETED);
        fun->flags = uint16_t(flagsword);
        fun->atom.init(atom);
        fun->initScript(script);
        if (!script->typeSetFunction(cx, fun))
            return false;
        JS_ASSERT(fun->nargs == fun->script()->bindings.numArgs());
        js_CallNewScriptHook(cx, fun->script(), fun);
        *objp = fun;
    }

bool
DefineGlobals(JSContext *cx, GlobalScope &globalScope, JSScript *script)
{
    JSObject *globalObj = globalScope.globalObj;

    /* Define and update global properties. */
    for (size_t i = 0; i < globalScope.defs.length(); i++) {
        GlobalScope::GlobalDef &def = globalScope.defs[i];

        /* Names that could be resolved ahead of time can be skipped. */
        if (!def.atom)
            continue;

        jsid id = ATOM_TO_JSID(def.atom);
        Value rval;

        if (def.funbox) {
            JSFunction *fun = def.funbox->function();

            /*
             * No need to check for redeclarations or anything, global
             * optimizations only take place if the property is not defined.
             */
            rval.setObject(*fun);
            types::AddTypePropertyId(cx, globalObj, id, rval);
        } else {
            rval.setUndefined();
        }

        /*
         * Don't update the type information when defining the property for the
         * global object, per the consistency rules for type properties. If the
         * property is only undefined before it is ever written, we can check
         * the global directly during compilation and avoid having to emit type
         * checks every time it is accessed in the script.
         */
        const Shape *shape =
            DefineNativeProperty(cx, globalObj, id, rval, JS_PropertyStub, JS_StrictPropertyStub,
                                 JSPROP_ENUMERATE | JSPROP_PERMANENT, 0, 0, DNP_SKIP_TYPE);
        if (!shape)
            return false;
        def.knownSlot = shape->slot();
    }

    Vector<JSScript *, 16> worklist(cx);
    if (!worklist.append(script))
        return false;

    /*
     * Recursively walk through all scripts we just compiled. For each script,
     * go through all global uses. Each global use indexes into globalScope->defs.
     * Use this information to repoint each use to the correct slot in the global
     * object.
     */
    while (worklist.length()) {
        JSScript *outer = worklist.back();
        worklist.popBack();

        if (JSScript::isValidOffset(outer->objectsOffset)) {
            JSObjectArray *arr = outer->objects();

            /*
             * If this is an eval script, don't treat the saved caller function
             * stored in the first object slot as an inner function.
             */
            size_t start = outer->savedCallerFun ? 1 : 0;

            for (size_t i = start; i < arr->length; i++) {
                JSObject *obj = arr->vector[i];
                if (!obj->isFunction())
                    continue;
                JSFunction *fun = obj->toFunction();
                JS_ASSERT(fun->isInterpreted());
                JSScript *inner = fun->script();
                if (outer->function() && outer->function()->isHeavyweight()) {
                    outer->isOuterFunction = true;
                    inner->isInnerFunction = true;
                }
                if (!JSScript::isValidOffset(inner->globalsOffset) &&
                    !JSScript::isValidOffset(inner->objectsOffset)) {
                    continue;
                }
                if (!worklist.append(inner))
                    return false;
            }
        }

        if (!JSScript::isValidOffset(outer->globalsOffset))
            continue;

        GlobalSlotArray *globalUses = outer->globals();
        uint32_t nGlobalUses = globalUses->length;
        for (uint32_t i = 0; i < nGlobalUses; i++) {
            uint32_t index = globalUses->vector[i].slot;
            JS_ASSERT(index < globalScope.defs.length());
            globalUses->vector[i].slot = globalScope.defs[index].knownSlot;
        }
    }

    return true;
//.........这里部分代码省略.........