jdk.nashorn.internal.runtime.linker.NashornCallSiteDescriptor Java Examples

@Override
public GuardedInvocation findGetMethod(final CallSiteDescriptor desc, final LinkRequest request) {
    final String name = NashornCallSiteDescriptor.getOperand(desc);
    final boolean isScope = NashornCallSiteDescriptor.isScope(desc);

    if (lexicalScope != null && isScope && !NashornCallSiteDescriptor.isApplyToCall(desc)) {
        if (lexicalScope.hasOwnProperty(name)) {
            return lexicalScope.findGetMethod(desc, request);
        }
    }

    final GuardedInvocation invocation =  super.findGetMethod(desc, request);

    // We want to avoid adding our generic lexical scope switchpoint to global constant invocations,
    // because those are invalidated per-key in the addBoundProperties method above.
    // We therefore check if the invocation does already have a switchpoint and the property is non-inherited,
    // assuming this only applies to global constants. If other non-inherited properties will
    // start using switchpoints some time in the future we'll have to revisit this.
    if (isScope && context.getEnv()._es6 && (invocation.getSwitchPoints() == null || !hasOwnProperty(name))) {
        return invocation.addSwitchPoint(getLexicalScopeSwitchPoint());
    }

    return invocation;
}
 

@Override
public GuardedInvocation findGetMethod(final CallSiteDescriptor desc, final LinkRequest request, final String operator) {
    final String name = desc.getNameToken(CallSiteDescriptor.NAME_OPERAND);
    final boolean isScope = NashornCallSiteDescriptor.isScope(desc);

    if (lexicalScope != null && isScope && !NashornCallSiteDescriptor.isApplyToCall(desc)) {
        if (lexicalScope.hasOwnProperty(name)) {
            return lexicalScope.findGetMethod(desc, request, operator);
        }
    }

    final GuardedInvocation invocation =  super.findGetMethod(desc, request, operator);

    // We want to avoid adding our generic lexical scope switchpoint to global constant invocations,
    // because those are invalidated per-key in the addBoundProperties method above.
    // We therefore check if the invocation does already have a switchpoint and the property is non-inherited,
    // assuming this only applies to global constants. If other non-inherited properties will
    // start using switchpoints some time in the future we'll have to revisit this.
    if (isScope && context.getEnv()._es6 && (invocation.getSwitchPoints() == null || !hasOwnProperty(name))) {
        return invocation.addSwitchPoint(getLexicalScopeSwitchPoint());
    }

    return invocation;
}
 

@SuppressWarnings("unused")
private static void setSpillWithNew(final CallSiteDescriptor desc, final PropertyMap oldMap, final PropertyMap newMap, final int index, final Object self, final Object value) {
    final ScriptObject obj      = (ScriptObject)self;
    final boolean      isStrict = NashornCallSiteDescriptor.isStrict(desc);

    if (!obj.isExtensible()) {
        if (isStrict) {
            throw typeError("object.non.extensible", desc.getNameToken(2), ScriptRuntime.safeToString(obj));
        }
    } else if (obj.compareAndSetMap(oldMap, newMap)) {
        obj.spill = new Object[SPILL_RATE];
        obj.spill[index] = value;
    } else {
        obj.set(desc.getNameToken(2), value, isStrict);
    }
}
 

@SuppressWarnings("unused")
private static void setSpillWithGrow(final CallSiteDescriptor desc, final PropertyMap oldMap, final PropertyMap newMap, final int index, final int newLength, final Object self, final Object value) {
    final ScriptObject obj      = (ScriptObject)self;
    final boolean      isStrict = NashornCallSiteDescriptor.isStrict(desc);

    if (!obj.isExtensible()) {
        if (isStrict) {
            throw typeError("object.non.extensible", desc.getNameToken(2), ScriptRuntime.safeToString(obj));
        }
    } else if (obj.compareAndSetMap(oldMap, newMap)) {
        final int oldLength = obj.spill.length;
        final Object[] newSpill = new Object[newLength];
        System.arraycopy(obj.spill, 0, newSpill, 0, oldLength);
        obj.spill = newSpill;
        obj.spill[index] = value;
    } else {
        obj.set(desc.getNameToken(2), value, isStrict);
    }
}
 

private static GuardedInvocation fixExpressionCallSite(final NashornCallSiteDescriptor desc, final GuardedInvocation link) {
    // If it's not a getMethod, just add an expression filter that converts WithObject in "this" position to its
    // expression.
    if(!"getMethod".equals(desc.getFirstOperator())) {
        return fixReceiverType(link, WITHEXPRESSIONFILTER).filterArguments(0, WITHEXPRESSIONFILTER);
    }

    final MethodHandle linkInvocation = link.getInvocation();
    final MethodType linkType = linkInvocation.type();
    final boolean linkReturnsFunction = ScriptFunction.class.isAssignableFrom(linkType.returnType());
    return link.replaceMethods(
            // Make sure getMethod will bind the script functions it receives to WithObject.expression
            MH.foldArguments(linkReturnsFunction ? BIND_TO_EXPRESSION_FN : BIND_TO_EXPRESSION_OBJ,
                    filter(linkInvocation.asType(linkType.changeReturnType(
                            linkReturnsFunction ? ScriptFunction.class : Object.class)), WITHEXPRESSIONFILTER)),
            // No clever things for the guard -- it is still identically filtered.
            filterGuard(link, WITHEXPRESSIONFILTER));
}
 

@Override
public GuardedInvocation findSetMethod(final CallSiteDescriptor desc, final LinkRequest request) {
    final boolean isScope = NashornCallSiteDescriptor.isScope(desc);

    if (lexicalScope != null && isScope) {
        final String name = desc.getNameToken(CallSiteDescriptor.NAME_OPERAND);
        if (lexicalScope.hasOwnProperty(name)) {
            return lexicalScope.findSetMethod(desc, request);
        }
    }

    final GuardedInvocation invocation = super.findSetMethod(desc, request);

    if (isScope && context.getEnv()._es6) {
        return invocation.addSwitchPoint(getLexicalScopeSwitchPoint());
    }

    return invocation;
}
 

@Override
public GuardedInvocation findSetMethod(final CallSiteDescriptor desc, final LinkRequest request) {
    final boolean isScope = NashornCallSiteDescriptor.isScope(desc);

    if (lexicalScope != null && isScope) {
        final String name = desc.getNameToken(CallSiteDescriptor.NAME_OPERAND);
        if (lexicalScope.hasOwnProperty(name)) {
            return lexicalScope.findSetMethod(desc, request);
        }
    }

    final GuardedInvocation invocation = super.findSetMethod(desc, request);

    if (isScope && context.getEnv()._es6) {
        return invocation.addSwitchPoint(getLexicalScopeSwitchPoint());
    }

    return invocation;
}
 

/**
 * Fall back if a function property is not found.
 * @param desc The call site descriptor
 * @param request the link request
 * @return GuardedInvocation to be invoked at call site.
 */
public GuardedInvocation noSuchMethod(final CallSiteDescriptor desc, final LinkRequest request) {
    final String       name      = desc.getNameToken(2);
    final FindProperty find      = findProperty(NO_SUCH_METHOD_NAME, true);
    final boolean      scopeCall = isScope() && NashornCallSiteDescriptor.isScope(desc);

    if (find == null) {
        return noSuchProperty(desc, request);
    }

    final Object value = getObjectValue(find);
    if (! (value instanceof ScriptFunction)) {
        return createEmptyGetter(desc, name);
    }

    final ScriptFunction func = (ScriptFunction)value;
    final Object thiz = scopeCall && func.isStrict() ? ScriptRuntime.UNDEFINED : this;
    // TODO: It'd be awesome if we could bind "name" without binding "this".
    return new GuardedInvocation(MH.dropArguments(MH.constant(ScriptFunction.class,
            func.makeBoundFunction(thiz, new Object[] { name })), 0, Object.class),
            null, NashornGuards.getMapGuard(getMap()));
}
 

private static GuardedInvocation fixExpressionCallSite(final NashornCallSiteDescriptor desc, final GuardedInvocation link) {
    // If it's not a getMethod, just add an expression filter that converts WithObject in "this" position to its
    // expression.
    if(!"getMethod".equals(desc.getFirstOperator())) {
        return fixReceiverType(link, WITHEXPRESSIONFILTER).filterArguments(0, WITHEXPRESSIONFILTER);
    }

    final MethodHandle linkInvocation = link.getInvocation();
    final MethodType linkType = linkInvocation.type();
    final boolean linkReturnsFunction = ScriptFunction.class.isAssignableFrom(linkType.returnType());
    return link.replaceMethods(
            // Make sure getMethod will bind the script functions it receives to WithObject.expression
            MH.foldArguments(linkReturnsFunction ? BIND_TO_EXPRESSION_FN : BIND_TO_EXPRESSION_OBJ,
                    filter(linkInvocation.asType(linkType.changeReturnType(
                            linkReturnsFunction ? ScriptFunction.class : Object.class)), WITHEXPRESSIONFILTER)),
            // No clever things for the guard -- it is still identically filtered.
            filterGuard(link, WITHEXPRESSIONFILTER));
}
 

/**
 * Return a fast linked array getter, or null if we have to dispatch to super class
 * @param desc     descriptor
 * @param request  link request
 * @return invocation or null if needs to be sent to slow relink
 */
@Override
public GuardedInvocation findFastGetIndexMethod(final Class<? extends ArrayData> clazz, final CallSiteDescriptor desc, final LinkRequest request) {
    final MethodType callType   = desc.getMethodType();
    final Class<?>   indexType  = callType.parameterType(1);
    final Class<?>   returnType = callType.returnType();

    if (ContinuousArrayData.class.isAssignableFrom(clazz) && indexType == int.class) {
        final Object[] args  = request.getArguments();
        final int      index = (int)args[args.length - 1];

        if (has(index)) {
            final MethodHandle getArray     = ScriptObject.GET_ARRAY.methodHandle();
            final int          programPoint = NashornCallSiteDescriptor.isOptimistic(desc) ? NashornCallSiteDescriptor.getProgramPoint(desc) : INVALID_PROGRAM_POINT;
            MethodHandle       getElement   = getElementGetter(returnType, programPoint);
            if (getElement != null) {
                getElement = MH.filterArguments(getElement, 0, MH.asType(getArray, getArray.type().changeReturnType(clazz)));
                final MethodHandle guard = MH.insertArguments(FAST_ACCESS_GUARD, 0, clazz);
                return new GuardedInvocation(getElement, guard, (SwitchPoint)null, ClassCastException.class);
            }
        }
    }

    return null;
}
 

/**
 * Fall back if a function property is not found.
 * @param desc The call site descriptor
 * @param request the link request
 * @return GuardedInvocation to be invoked at call site.
 */
public GuardedInvocation noSuchMethod(final CallSiteDescriptor desc, final LinkRequest request) {
    final String       name      = desc.getNameToken(2);
    final FindProperty find      = findProperty(NO_SUCH_METHOD_NAME, true);
    final boolean      scopeCall = isScope() && NashornCallSiteDescriptor.isScope(desc);

    if (find == null) {
        return noSuchProperty(desc, request);
    }

    final Object value = getObjectValue(find);
    if (! (value instanceof ScriptFunction)) {
        return createEmptyGetter(desc, name);
    }

    final ScriptFunction func = (ScriptFunction)value;
    final Object thiz = scopeCall && func.isStrict() ? ScriptRuntime.UNDEFINED : this;
    // TODO: It'd be awesome if we could bind "name" without binding "this".
    return new GuardedInvocation(MH.dropArguments(MH.constant(ScriptFunction.class,
            func.makeBoundFunction(thiz, new Object[] { name })), 0, Object.class),
            null, NashornGuards.getMapGuard(getMap()));
}
 

/**
 * Fall back if a function property is not found.
 * @param desc The call site descriptor
 * @param request the link request
 * @return GuardedInvocation to be invoked at call site.
 */
public GuardedInvocation noSuchMethod(final CallSiteDescriptor desc, final LinkRequest request) {
    final String       name      = desc.getNameToken(2);
    final FindProperty find      = findProperty(NO_SUCH_METHOD_NAME, true);
    final boolean      scopeCall = isScope() && NashornCallSiteDescriptor.isScope(desc);

    if (find == null) {
        return noSuchProperty(desc, request);
    }

    final Object value = getObjectValue(find);
    if (! (value instanceof ScriptFunction)) {
        return createEmptyGetter(desc, name);
    }

    final ScriptFunction func = (ScriptFunction)value;
    final Object thiz = scopeCall && func.isStrict() ? ScriptRuntime.UNDEFINED : this;
    // TODO: It'd be awesome if we could bind "name" without binding "this".
    return new GuardedInvocation(MH.dropArguments(MH.constant(ScriptFunction.class,
            func.makeBoundFunction(thiz, new Object[] { name })), 0, Object.class),
            null, NashornGuards.getMapGuard(getMap()));
}
 

/**
 * Given a guarded invocation and a callsite descriptor, perform return value filtering
 * according to the optimistic type coercion rules, using the return value from the descriptor
 * @param inv the invocation
 * @param desc the descriptor
 * @return filtered invocation
 */
public static GuardedInvocation filterOptimisticReturnValue(final GuardedInvocation inv, final CallSiteDescriptor desc) {
    if(!NashornCallSiteDescriptor.isOptimistic(desc)) {
        return inv;
    }
    return inv.replaceMethods(filterOptimisticReturnValue(inv.getInvocation(), desc.getMethodType().returnType(),
            NashornCallSiteDescriptor.getProgramPoint(desc)), inv.getGuard());
}
 

private void checkStrictCreateNewVariable() {
    // In strict mode, assignment can not create a new variable.
    // See also ECMA Annex C item 4. ReferenceError is thrown.
    if (NashornCallSiteDescriptor.isScope(desc) && NashornCallSiteDescriptor.isStrict(desc)) {
        throw referenceError("not.defined", getName());
    }
}
 

/**
 * Find a handle for a getIndex method
 * @param returnType     return type for getter
 * @param name           name
 * @param elementType    index type for getter
 * @param desc           call site descriptor
 * @return method handle for getter
 */
private static MethodHandle findGetIndexMethodHandle(final Class<?> returnType, final String name, final Class<?> elementType, final CallSiteDescriptor desc) {
    if (!returnType.isPrimitive()) {
        return findOwnMH_V(name, returnType, elementType);
    }

    return MH.insertArguments(
            findOwnMH_V(name, returnType, elementType, int.class),
            2,
            NashornCallSiteDescriptor.isOptimistic(desc) ?
                    NashornCallSiteDescriptor.getProgramPoint(desc) :
                    INVALID_PROGRAM_POINT);
}
 

private void checkStrictCreateNewVariable() {
    // In strict mode, assignment can not create a new variable.
    // See also ECMA Annex C item 4. ReferenceError is thrown.
    if (NashornCallSiteDescriptor.isScope(desc) && NashornCallSiteDescriptor.isStrict(desc)) {
        throw referenceError("not.defined", getName());
    }
}
 

private GuardedInvocation createEmptyGetter(final CallSiteDescriptor desc, final boolean explicitInstanceOfCheck, final String name) {
    if (NashornCallSiteDescriptor.isOptimistic(desc)) {
        throw new UnwarrantedOptimismException(UNDEFINED, NashornCallSiteDescriptor.getProgramPoint(desc), Type.OBJECT);
    }

    return new GuardedInvocation(Lookup.emptyGetter(desc.getMethodType().returnType()),
            NashornGuards.getMapGuard(getMap(), explicitInstanceOfCheck), getProtoSwitchPoints(name, null),
            explicitInstanceOfCheck ? null : ClassCastException.class);
}
 

/**
 * Fall back if a function property is not found.
 * @param desc The call site descriptor
 * @param request the link request
 * @return GuardedInvocation to be invoked at call site.
 */
public GuardedInvocation noSuchMethod(final CallSiteDescriptor desc, final LinkRequest request) {
    final String       name      = desc.getNameToken(2);
    final FindProperty find      = findProperty(NO_SUCH_METHOD_NAME, true);
    final boolean      scopeCall = isScope() && NashornCallSiteDescriptor.isScope(desc);

    if (find == null) {
        return noSuchProperty(desc, request);
    }

    final boolean explicitInstanceOfCheck = explicitInstanceOfCheck(desc, request);

    final Object value = find.getObjectValue();
    if (!(value instanceof ScriptFunction)) {
        return createEmptyGetter(desc, explicitInstanceOfCheck, name);
    }

    final ScriptFunction func = (ScriptFunction)value;
    final Object         thiz = scopeCall && func.isStrict() ? UNDEFINED : this;
    // TODO: It'd be awesome if we could bind "name" without binding "this".
    // Since we're binding this we must use an identity guard here.
    return new GuardedInvocation(
            MH.dropArguments(
                    MH.constant(
                            ScriptFunction.class,
                            func.createBound(thiz, new Object[] { name })),
                    0,
                    Object.class),
            NashornGuards.combineGuards(
                    NashornGuards.getIdentityGuard(this),
                    NashornGuards.getMapGuard(getMap(), true)));
}
 

/**
 * Lookup the appropriate method for an invoke dynamic call.
 * @param desc The invoke dynamic callsite descriptor.
 * @return GuardedInvocation to be invoked at call site.
 */
public static GuardedInvocation lookup(final CallSiteDescriptor desc) {
    final String operator = CallSiteDescriptorFactory.tokenizeOperators(desc).get(0);

    switch (operator) {
    case "new":
    case "call": {
        final String name = NashornCallSiteDescriptor.getFunctionDescription(desc);
        final String msg = name != null? "not.a.function" : "cant.call.undefined";
        throw typeError(msg, name);
    }

    case "callMethod":
        throw lookupTypeError("cant.read.property.of.undefined", desc);
    // NOTE: we support getElem and setItem as JavaScript doesn't distinguish items from properties. Nashorn itself
    // emits "dyn:getProp:identifier" for "<expr>.<identifier>" and "dyn:getElem" for "<expr>[<expr>]", but we are
    // more flexible here and dispatch not on operation name (getProp vs. getElem), but rather on whether the
    // operation has an associated name or not.
    case "getProp":
    case "getElem":
    case "getMethod":
        if (desc.getNameTokenCount() < 3) {
            return findGetIndexMethod(desc);
        }
        return findGetMethod(desc);
    case "setProp":
    case "setElem":
        if (desc.getNameTokenCount() < 3) {
            return findSetIndexMethod(desc);
        }
        return findSetMethod(desc);
    default:
        break;
    }

    return null;
}
 

private GuardedInvocation createEmptyGetter(final CallSiteDescriptor desc, final boolean explicitInstanceOfCheck, final String name) {
    if (NashornCallSiteDescriptor.isOptimistic(desc)) {
        throw new UnwarrantedOptimismException(UNDEFINED, NashornCallSiteDescriptor.getProgramPoint(desc), Type.OBJECT);
    }

    return new GuardedInvocation(Lookup.emptyGetter(desc.getMethodType().returnType()),
            NashornGuards.getMapGuard(getMap(), explicitInstanceOfCheck), getProtoSwitchPoints(name, null),
            explicitInstanceOfCheck ? null : ClassCastException.class);
}
 

/**
 * Fall back if a property is not found.
 * @param desc the call site descriptor.
 * @param request the link request
 * @return GuardedInvocation to be invoked at call site.
 */
@SuppressWarnings("null")
public GuardedInvocation noSuchProperty(final CallSiteDescriptor desc, final LinkRequest request) {
    final String name = desc.getNameToken(CallSiteDescriptor.NAME_OPERAND);
    final FindProperty find = findProperty(NO_SUCH_PROPERTY_NAME, true);
    final boolean scopeAccess = isScope() && NashornCallSiteDescriptor.isScope(desc);

    if (find != null) {
        final Object   value        = getObjectValue(find);
        ScriptFunction func         = null;
        MethodHandle   methodHandle = null;

        if (value instanceof ScriptFunction) {
            func = (ScriptFunction)value;
            methodHandle = getCallMethodHandle(func, desc.getMethodType(), name);
        }

        if (methodHandle != null) {
            if (scopeAccess && func.isStrict()) {
                methodHandle = bindTo(methodHandle, UNDEFINED);
            }
            return new GuardedInvocation(methodHandle,
                    find.isInherited()? getMap().getProtoGetSwitchPoint(proto, NO_SUCH_PROPERTY_NAME) : null,
                    getKnownFunctionPropertyGuard(getMap(), find.getGetter(Object.class), find.getOwner(), func));
        }
    }

    if (scopeAccess) {
        throw referenceError("not.defined", name);
    }

    return createEmptyGetter(desc, name);
}
 

/**
 * Fall back if a function property is not found.
 * @param desc The call site descriptor
 * @param request the link request
 * @return GuardedInvocation to be invoked at call site.
 */
public GuardedInvocation noSuchMethod(final CallSiteDescriptor desc, final LinkRequest request) {
    final String       name      = desc.getNameToken(2);
    final FindProperty find      = findProperty(NO_SUCH_METHOD_NAME, true);
    final boolean      scopeCall = isScope() && NashornCallSiteDescriptor.isScope(desc);

    if (find == null) {
        return noSuchProperty(desc, request);
    }

    final boolean explicitInstanceOfCheck = explicitInstanceOfCheck(desc, request);

    final Object value = find.getObjectValue();
    if (!(value instanceof ScriptFunction)) {
        return createEmptyGetter(desc, explicitInstanceOfCheck, name);
    }

    final ScriptFunction func = (ScriptFunction)value;
    final Object         thiz = scopeCall && func.isStrict() ? UNDEFINED : this;
    // TODO: It'd be awesome if we could bind "name" without binding "this".
    // Since we're binding this we must use an identity guard here.
    return new GuardedInvocation(
            MH.dropArguments(
                    MH.constant(
                            ScriptFunction.class,
                            func.createBound(thiz, new Object[] { name })),
                    0,
                    Object.class),
            NashornGuards.combineGuards(
                    NashornGuards.getIdentityGuard(this),
                    NashornGuards.getMapGuard(getMap(), true)));
}
 

@SuppressWarnings("unchecked")
private static LinkedList<RuntimeEvent<?>> getEventQueue(final Object self) {
    final ScriptObject sobj = (ScriptObject)self;
    LinkedList<RuntimeEvent<?>> q;
    if (sobj.has(EVENT_QUEUE)) {
        q = (LinkedList<RuntimeEvent<?>>)((ScriptObject)self).get(EVENT_QUEUE);
    } else {
        ((ScriptObject)self).set(EVENT_QUEUE, q = new LinkedList<>(), NashornCallSiteDescriptor.CALLSITE_STRICT);
    }
    return q;
}
 

/**
 * Lookup the appropriate method for an invoke dynamic call.
 * @param desc The invoke dynamic callsite descriptor.
 * @return GuardedInvocation to be invoked at call site.
 */
public static GuardedInvocation lookup(final CallSiteDescriptor desc) {
    final String operator = CallSiteDescriptorFactory.tokenizeOperators(desc).get(0);

    switch (operator) {
    case "new":
    case "call": {
        final String name = NashornCallSiteDescriptor.getFunctionDescription(desc);
        final String msg = name != null? "not.a.function" : "cant.call.undefined";
        throw typeError(msg, name);
    }

    case "callMethod":
        throw lookupTypeError("cant.read.property.of.undefined", desc);
    // NOTE: we support getElem and setItem as JavaScript doesn't distinguish items from properties. Nashorn itself
    // emits "dyn:getProp:identifier" for "<expr>.<identifier>" and "dyn:getElem" for "<expr>[<expr>]", but we are
    // more flexible here and dispatch not on operation name (getProp vs. getElem), but rather on whether the
    // operation has an associated name or not.
    case "getProp":
    case "getElem":
    case "getMethod":
        if (desc.getNameTokenCount() < 3) {
            return findGetIndexMethod(desc);
        }
        return findGetMethod(desc);
    case "setProp":
    case "setElem":
        if (desc.getNameTokenCount() < 3) {
            return findSetIndexMethod(desc);
        }
        return findSetMethod(desc);
    default:
        break;
    }

    return null;
}
 

/**
 * Generate a dynamic call
 *
 * @param returnType return type
 * @param argCount   number of arguments
 * @param flags      callsite flags
 * @param msg        additional message to be used when reporting error
 *
 * @return the method emitter
 */
MethodEmitter dynamicCall(final Type returnType, final int argCount, final int flags, final String msg) {
    debug("dynamic_call", "args=", argCount, "returnType=", returnType);
    final String signature = getDynamicSignature(returnType, argCount); // +1 because the function itself is the 1st parameter for dynamic calls (what you call - call target)
    debug("   signature", signature);
    method.visitInvokeDynamicInsn(
            msg != null && msg.length() < LARGE_STRING_THRESHOLD? NameCodec.encode(msg) : EMPTY_NAME,
            signature, LINKERBOOTSTRAP, flags | NashornCallSiteDescriptor.CALL);
    pushType(returnType);

    return this;
}
 

/**
 * Lookup the appropriate method for an invoke dynamic call.
 * @param desc The invoke dynamic callsite descriptor.
 * @return GuardedInvocation to be invoked at call site.
 */
public static GuardedInvocation lookup(final CallSiteDescriptor desc) {
    final String operator = CallSiteDescriptorFactory.tokenizeOperators(desc).get(0);

    switch (operator) {
    case "new":
    case "call": {
        final String name = NashornCallSiteDescriptor.getFunctionDescription(desc);
        final String msg = name != null? "not.a.function" : "cant.call.undefined";
        throw typeError(msg, name);
    }

    case "callMethod":
        throw lookupTypeError("cant.read.property.of.undefined", desc);
    // NOTE: we support getElem and setItem as JavaScript doesn't distinguish items from properties. Nashorn itself
    // emits "dyn:getProp:identifier" for "<expr>.<identifier>" and "dyn:getElem" for "<expr>[<expr>]", but we are
    // more flexible here and dispatch not on operation name (getProp vs. getElem), but rather on whether the
    // operation has an associated name or not.
    case "getProp":
    case "getElem":
    case "getMethod":
        if (desc.getNameTokenCount() < 3) {
            return findGetIndexMethod(desc);
        }
        return findGetMethod(desc);
    case "setProp":
    case "setElem":
        if (desc.getNameTokenCount() < 3) {
            return findSetIndexMethod(desc);
        }
        return findSetMethod(desc);
    default:
        break;
    }

    return null;
}
 

static MethodHandle getINVOKE_UA_GETTER(final Class<?> returnType, final int programPoint) {
    if (UnwarrantedOptimismException.isValid(programPoint)) {
        final int flags = NashornCallSiteDescriptor.CALLSITE_OPTIMISTIC | programPoint << CALLSITE_PROGRAM_POINT_SHIFT;
        return Bootstrap.createDynamicInvoker("dyn:call", flags, returnType, Object.class, Object.class);
    } else {
        return Bootstrap.createDynamicInvoker("dyn:call", Object.class, Object.class, Object.class);
    }
}
 

private void checkStrictCreateNewVariable() {
    // In strict mode, assignment can not create a new variable.
    // See also ECMA Annex C item 4. ReferenceError is thrown.
    if (NashornCallSiteDescriptor.isScope(desc) && NashornCallSiteDescriptor.isStrict(desc)) {
        throw referenceError("not.defined", getName());
    }
}
 

private static GuardedInvocation fixExpressionCallSite(final NashornCallSiteDescriptor desc, final GuardedInvocation link) {
    // If it's not a getMethod, just add an expression filter that converts WithObject in "this" position to its
    // expression.
    if (!"getMethod".equals(desc.getFirstOperator())) {
        return fixReceiverType(link, WITHEXPRESSIONFILTER).filterArguments(0, WITHEXPRESSIONFILTER);
    }

    final MethodHandle linkInvocation      = link.getInvocation();
    final MethodType   linkType            = linkInvocation.type();
    final boolean      linkReturnsFunction = ScriptFunction.class.isAssignableFrom(linkType.returnType());

    return link.replaceMethods(
            // Make sure getMethod will bind the script functions it receives to WithObject.expression
            MH.foldArguments(
                    linkReturnsFunction ?
                            BIND_TO_EXPRESSION_FN :
                            BIND_TO_EXPRESSION_OBJ,
                    filterReceiver(
                            linkInvocation.asType(
                                    linkType.changeReturnType(
                                            linkReturnsFunction ?
                                                    ScriptFunction.class :
                                                    Object.class).
                                                        changeParameterType(
                                                                0,
                                                                Object.class)),
                                    WITHEXPRESSIONFILTER)),
                     filterGuardReceiver(link, WITHEXPRESSIONFILTER));
 // No clever things for the guard -- it is still identically filtered.

}
 

/**
 * Handle creation of new attribute.
 * @param desc the call site descriptor
 * @param request the link request
 * @return Link to be invoked at call site.
 */
@Override
public GuardedInvocation noSuchProperty(final CallSiteDescriptor desc, final LinkRequest request) {
    final String propertyName = NashornCallSiteDescriptor.getOperand(desc);
    createProperty(propertyName);
    return super.lookup(desc, request);
}