/* * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package jdk.nashorn.internal.runtime.linker; import static jdk.nashorn.internal.lookup.Lookup.MH; import static jdk.nashorn.internal.runtime.ECMAErrors.typeError; import java.lang.invoke.MethodHandle; import java.lang.invoke.MethodHandles; import java.lang.invoke.MethodType; import java.lang.invoke.SwitchPoint; import jdk.internal.dynalink.CallSiteDescriptor; import jdk.internal.dynalink.linker.GuardedInvocation; import jdk.internal.dynalink.linker.LinkRequest; import jdk.internal.dynalink.support.CallSiteDescriptorFactory; import jdk.internal.dynalink.support.Guards; import jdk.nashorn.internal.runtime.Context; import jdk.nashorn.internal.runtime.FindProperty; import jdk.nashorn.internal.runtime.GlobalConstants; import jdk.nashorn.internal.runtime.JSType; import jdk.nashorn.internal.runtime.ScriptObject; import jdk.nashorn.internal.runtime.ScriptRuntime; import jdk.nashorn.internal.runtime.UserAccessorProperty; /** * Implements lookup of methods to link for dynamic operations on JavaScript primitive values (booleans, strings, and * numbers). This class is only public so it can be accessed by classes in the {@code jdk.nashorn.internal.objects} * package. */ public final class PrimitiveLookup { /** Method handle to link setters on primitive base. See ES5 8.7.2. */ private static final MethodHandle PRIMITIVE_SETTER = findOwnMH("primitiveSetter", MH.type(void.class, ScriptObject.class, Object.class, Object.class, boolean.class, Object.class)); private PrimitiveLookup() { } /** * Returns a guarded invocation representing the linkage for a dynamic operation on a primitive Java value. * @param request the link request for the dynamic call site. * @param receiverClass the class of the receiver value (e.g., {@link java.lang.Boolean}, {@link java.lang.String} etc.) * @param wrappedReceiver a transient JavaScript native wrapper object created as the object proxy for the primitive * value; see ECMAScript 5.1, section 8.7.1 for discussion of using {@code [[Get]]} on a property reference with a * primitive base value. This instance will be used to delegate actual lookup. * @param wrapFilter A method handle that takes a primitive value of type specified in the {@code receiverClass} and * creates a transient native wrapper of the same type as {@code wrappedReceiver} for subsequent invocations of the * method - it will be combined into the returned invocation as an argument filter on the receiver. * @return a guarded invocation representing the operation at the call site when performed on a JavaScript primitive * @param protoFilter A method handle that walks up the proto chain of this receiver object * type {@code receiverClass}. */ public static GuardedInvocation lookupPrimitive(final LinkRequest request, final Class receiverClass, final ScriptObject wrappedReceiver, final MethodHandle wrapFilter, final MethodHandle protoFilter) { return lookupPrimitive(request, Guards.getInstanceOfGuard(receiverClass), wrappedReceiver, wrapFilter, protoFilter); } /** * Returns a guarded invocation representing the linkage for a dynamic operation on a primitive Java value. * @param request the link request for the dynamic call site. * @param guard an explicit guard that will be used for the returned guarded invocation. * @param wrappedReceiver a transient JavaScript native wrapper object created as the object proxy for the primitive * value; see ECMAScript 5.1, section 8.7.1 for discussion of using {@code [[Get]]} on a property reference with a * primitive base value. This instance will be used to delegate actual lookup. * @param wrapFilter A method handle that takes a primitive value of type guarded by the {@code guard} and * creates a transient native wrapper of the same type as {@code wrappedReceiver} for subsequent invocations of the * method - it will be combined into the returned invocation as an argument filter on the receiver. * @param protoFilter A method handle that walks up the proto chain of this receiver object * @return a guarded invocation representing the operation at the call site when performed on a JavaScript primitive * type (that is implied by both {@code guard} and {@code wrappedReceiver}). */ public static GuardedInvocation lookupPrimitive(final LinkRequest request, final MethodHandle guard, final ScriptObject wrappedReceiver, final MethodHandle wrapFilter, final MethodHandle protoFilter) { final CallSiteDescriptor desc = request.getCallSiteDescriptor(); final String name; final FindProperty find; if (desc.getNameTokenCount() > 2) { name = desc.getNameToken(CallSiteDescriptor.NAME_OPERAND); find = wrappedReceiver.findProperty(name, true); } else { name = null; find = null; } final String firstOp = CallSiteDescriptorFactory.tokenizeOperators(desc).get(0); switch (firstOp) { case "getProp": case "getElem": case "getMethod": //checks whether the property name is hard-coded in the call-site (i.e. a getProp vs a getElem, or setProp vs setElem) //if it is we can make assumptions on the property: that if it is not defined on primitive wrapper itself it never will be. //so in that case we can skip creation of primitive wrapper and start our search with the prototype. if (name != null) { if (find == null) { // Give up early, give chance to BeanLinker and NashornBottomLinker to deal with it. return null; } final SwitchPoint sp = find.getProperty().getBuiltinSwitchPoint(); //can use this instead of proto filter if (sp instanceof Context.BuiltinSwitchPoint && !sp.hasBeenInvalidated()) { return new GuardedInvocation(GlobalConstants.staticConstantGetter(find.getObjectValue()), guard, sp, null); } if (find.isInherited() && !(find.getProperty() instanceof UserAccessorProperty)) { // If property is found in the prototype object bind the method handle directly to // the proto filter instead of going through wrapper instantiation below. final ScriptObject proto = wrappedReceiver.getProto(); final GuardedInvocation link = proto.lookup(desc, request); if (link != null) { final MethodHandle invocation = link.getInvocation(); //this contains the builtin switchpoint final MethodHandle adaptedInvocation = MH.asType(invocation, invocation.type().changeParameterType(0, Object.class)); final MethodHandle method = MH.filterArguments(adaptedInvocation, 0, protoFilter); final MethodHandle protoGuard = MH.filterArguments(link.getGuard(), 0, protoFilter); return new GuardedInvocation(method, NashornGuards.combineGuards(guard, protoGuard)); } } } break; case "setProp": case "setElem": return getPrimitiveSetter(name, guard, wrapFilter, NashornCallSiteDescriptor.isStrict(desc)); default: break; } final GuardedInvocation link = wrappedReceiver.lookup(desc, request); if (link != null) { MethodHandle method = link.getInvocation(); final Class receiverType = method.type().parameterType(0); if (receiverType != Object.class) { final MethodType wrapType = wrapFilter.type(); assert receiverType.isAssignableFrom(wrapType.returnType()); method = MH.filterArguments(method, 0, MH.asType(wrapFilter, wrapType.changeReturnType(receiverType))); } return new GuardedInvocation(method, guard, link.getSwitchPoints(), null); } return null; } private static GuardedInvocation getPrimitiveSetter(final String name, final MethodHandle guard, final MethodHandle wrapFilter, final boolean isStrict) { MethodHandle filter = MH.asType(wrapFilter, wrapFilter.type().changeReturnType(ScriptObject.class)); final MethodHandle target; if (name == null) { filter = MH.dropArguments(filter, 1, Object.class, Object.class); target = MH.insertArguments(PRIMITIVE_SETTER, 3, isStrict); } else { filter = MH.dropArguments(filter, 1, Object.class); target = MH.insertArguments(PRIMITIVE_SETTER, 2, name, isStrict); } return new GuardedInvocation(MH.foldArguments(target, filter), guard); } @SuppressWarnings("unused") private static void primitiveSetter(final ScriptObject wrappedSelf, final Object self, final Object key, final boolean strict, final Object value) { // See ES5.1 8.7.2 PutValue (V, W) final String name = JSType.toString(key); final FindProperty find = wrappedSelf.findProperty(name, true); if (find == null || !(find.getProperty() instanceof UserAccessorProperty) || !find.getProperty().isWritable()) { if (strict) { throw typeError("property.not.writable", name, ScriptRuntime.safeToString(self)); } return; } // property found and is a UserAccessorProperty find.setValue(value, strict); } private static MethodHandle findOwnMH(final String name, final MethodType type) { return MH.findStatic(MethodHandles.lookup(), PrimitiveLookup.class, name, type); } }