| /* |
| * 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; |
| |
| import static jdk.nashorn.internal.codegen.CompilerConstants.virtualCallNoLookup; |
| import static jdk.nashorn.internal.lookup.Lookup.MH; |
| import static jdk.nashorn.internal.runtime.ECMAErrors.typeError; |
| import static jdk.nashorn.internal.runtime.ScriptRuntime.UNDEFINED; |
| |
| import java.lang.invoke.MethodHandle; |
| import java.lang.invoke.MethodHandles; |
| import java.lang.invoke.MethodType; |
| import jdk.internal.dynalink.CallSiteDescriptor; |
| import jdk.internal.dynalink.linker.GuardedInvocation; |
| import jdk.internal.dynalink.linker.LinkRequest; |
| import jdk.nashorn.internal.codegen.CompilerConstants.Call; |
| import jdk.nashorn.internal.lookup.MethodHandleFactory; |
| import jdk.nashorn.internal.runtime.linker.NashornCallSiteDescriptor; |
| import jdk.nashorn.internal.runtime.linker.NashornGuards; |
| |
| /** |
| * Runtime representation of a JavaScript function. |
| */ |
| public abstract class ScriptFunction extends ScriptObject { |
| |
| /** Method handle for prototype getter for this ScriptFunction */ |
| public static final MethodHandle G$PROTOTYPE = findOwnMH("G$prototype", Object.class, Object.class); |
| |
| /** Method handle for prototype setter for this ScriptFunction */ |
| public static final MethodHandle S$PROTOTYPE = findOwnMH("S$prototype", void.class, Object.class, Object.class); |
| |
| /** Method handle for length getter for this ScriptFunction */ |
| public static final MethodHandle G$LENGTH = findOwnMH("G$length", int.class, Object.class); |
| |
| /** Method handle for name getter for this ScriptFunction */ |
| public static final MethodHandle G$NAME = findOwnMH("G$name", Object.class, Object.class); |
| |
| /** Method handle used for implementing sync() in mozilla_compat */ |
| public static final MethodHandle INVOKE_SYNC = findOwnMH("invokeSync", Object.class, ScriptFunction.class, Object.class, Object.class, Object[].class); |
| |
| /** Method handle for allocate function for this ScriptFunction */ |
| static final MethodHandle ALLOCATE = findOwnMH("allocate", Object.class); |
| |
| private static final MethodHandle WRAPFILTER = findOwnMH("wrapFilter", Object.class, Object.class); |
| |
| /** method handle to scope getter for this ScriptFunction */ |
| public static final Call GET_SCOPE = virtualCallNoLookup(ScriptFunction.class, "getScope", ScriptObject.class); |
| |
| private static final MethodHandle IS_FUNCTION_MH = findOwnMH("isFunctionMH", boolean.class, Object.class, ScriptFunctionData.class); |
| |
| private static final MethodHandle IS_NONSTRICT_FUNCTION = findOwnMH("isNonStrictFunction", boolean.class, Object.class, Object.class, ScriptFunctionData.class); |
| |
| private static final MethodHandle ADD_ZEROTH_ELEMENT = findOwnMH("addZerothElement", Object[].class, Object[].class, Object.class); |
| |
| /** The parent scope. */ |
| private final ScriptObject scope; |
| |
| private final ScriptFunctionData data; |
| |
| /** |
| * Constructor |
| * |
| * @param name function name |
| * @param methodHandle method handle to function (if specializations are present, assumed to be most generic) |
| * @param map property map |
| * @param scope scope |
| * @param specs specialized version of this function - other method handles |
| * @param strict is this a strict mode function? |
| * @param builtin is this a built in function? |
| * @param isConstructor is this a constructor? |
| */ |
| protected ScriptFunction( |
| final String name, |
| final MethodHandle methodHandle, |
| final PropertyMap map, |
| final ScriptObject scope, |
| final MethodHandle[] specs, |
| final boolean strict, |
| final boolean builtin, |
| final boolean isConstructor) { |
| |
| this(new FinalScriptFunctionData(name, methodHandle, specs, strict, builtin, isConstructor), map, scope); |
| } |
| |
| /** |
| * Constructor |
| * |
| * @param data static function data |
| * @param map property map |
| * @param scope scope |
| */ |
| protected ScriptFunction( |
| final ScriptFunctionData data, |
| final PropertyMap map, |
| final ScriptObject scope) { |
| |
| super(map); |
| |
| if (Context.DEBUG) { |
| constructorCount++; |
| } |
| |
| this.data = data; |
| this.scope = scope; |
| } |
| |
| @Override |
| public String getClassName() { |
| return "Function"; |
| } |
| |
| /** |
| * ECMA 15.3.5.3 [[HasInstance]] (V) |
| * Step 3 if "prototype" value is not an Object, throw TypeError |
| */ |
| @Override |
| public boolean isInstance(final ScriptObject instance) { |
| final Object basePrototype = getTargetFunction().getPrototype(); |
| if (!(basePrototype instanceof ScriptObject)) { |
| throw typeError("prototype.not.an.object", ScriptRuntime.safeToString(getTargetFunction()), ScriptRuntime.safeToString(basePrototype)); |
| } |
| |
| for (ScriptObject proto = instance.getProto(); proto != null; proto = proto.getProto()) { |
| if (proto == basePrototype) { |
| return true; |
| } |
| } |
| |
| return false; |
| } |
| |
| /** |
| * Returns the target function for this function. If the function was not created using |
| * {@link #makeBoundFunction(Object, Object[])}, its target function is itself. If it is bound, its target function |
| * is the target function of the function it was made from (therefore, the target function is always the final, |
| * unbound recipient of the calls). |
| * @return the target function for this function. |
| */ |
| protected ScriptFunction getTargetFunction() { |
| return this; |
| } |
| |
| boolean isBoundFunction() { |
| return getTargetFunction() != this; |
| } |
| |
| /** |
| * Set the arity of this ScriptFunction |
| * @param arity arity |
| */ |
| public final void setArity(final int arity) { |
| data.setArity(arity); |
| } |
| |
| /** |
| * Is this a ECMAScript 'use strict' function? |
| * @return true if function is in strict mode |
| */ |
| public boolean isStrict() { |
| return data.isStrict(); |
| } |
| |
| /** |
| * Returns true if this is a non-strict, non-built-in function that requires non-primitive this argument |
| * according to ECMA 10.4.3. |
| * @return true if this argument must be an object |
| */ |
| public boolean needsWrappedThis() { |
| return data.needsWrappedThis(); |
| } |
| |
| /** |
| * Execute this script function. |
| * @param self Target object. |
| * @param arguments Call arguments. |
| * @return ScriptFunction result. |
| * @throws Throwable if there is an exception/error with the invocation or thrown from it |
| */ |
| Object invoke(final Object self, final Object... arguments) throws Throwable { |
| if (Context.DEBUG) { |
| invokes++; |
| } |
| return data.invoke(this, self, arguments); |
| } |
| |
| /** |
| * Execute this script function as a constructor. |
| * @param arguments Call arguments. |
| * @return Newly constructed result. |
| * @throws Throwable if there is an exception/error with the invocation or thrown from it |
| */ |
| Object construct(final Object... arguments) throws Throwable { |
| return data.construct(this, arguments); |
| } |
| |
| /** |
| * Allocate function. Called from generated {@link ScriptObject} code |
| * for allocation as a factory method |
| * |
| * @return a new instance of the {@link ScriptObject} whose allocator this is |
| */ |
| @SuppressWarnings("unused") |
| private Object allocate() { |
| if (Context.DEBUG) { |
| allocations++; |
| } |
| assert !isBoundFunction(); // allocate never invoked on bound functions |
| |
| final ScriptObject object = data.allocate(); |
| |
| if (object != null) { |
| Object prototype = getPrototype(); |
| if (prototype instanceof ScriptObject) { |
| object.setProto((ScriptObject)prototype); |
| } |
| |
| if (object.getProto() == null) { |
| object.setProto(getObjectPrototype()); |
| } |
| } |
| |
| return object; |
| } |
| |
| /** |
| * Return Object.prototype - used by "allocate" |
| * @return Object.prototype |
| */ |
| protected abstract ScriptObject getObjectPrototype(); |
| |
| /** |
| * Creates a version of this function bound to a specific "self" and other arguments, as per |
| * {@code Function.prototype.bind} functionality in ECMAScript 5.1 section 15.3.4.5. |
| * @param self the self to bind to this function. Can be null (in which case, null is bound as this). |
| * @param args additional arguments to bind to this function. Can be null or empty to not bind additional arguments. |
| * @return a function with the specified self and parameters bound. |
| */ |
| protected ScriptFunction makeBoundFunction(final Object self, final Object[] args) { |
| return makeBoundFunction(data.makeBoundFunctionData(this, self, args)); |
| } |
| |
| /** |
| * Create a version of this function as in {@link ScriptFunction#makeBoundFunction(Object, Object[])}, |
| * but using a {@link ScriptFunctionData} for the bound data. |
| * |
| * @param boundData ScriptFuntionData for the bound function |
| * @return a function with the bindings performed according to the given data |
| */ |
| protected abstract ScriptFunction makeBoundFunction(ScriptFunctionData boundData); |
| |
| @Override |
| public final String safeToString() { |
| return toSource(); |
| } |
| |
| @Override |
| public String toString() { |
| return data.toString(); |
| } |
| |
| /** |
| * Get this function as a String containing its source code. If no source code |
| * exists in this ScriptFunction, its contents will be displayed as {@code [native code]} |
| * @return string representation of this function's source |
| */ |
| public final String toSource() { |
| return data.toSource(); |
| } |
| |
| /** |
| * Get the prototype object for this function |
| * @return prototype |
| */ |
| public abstract Object getPrototype(); |
| |
| /** |
| * Set the prototype object for this function |
| * @param prototype new prototype object |
| */ |
| public abstract void setPrototype(Object prototype); |
| |
| /** |
| * Create a function that invokes this function synchronized on {@code sync} or the self object |
| * of the invocation. |
| * @param sync the Object to synchronize on, or undefined |
| * @return synchronized function |
| */ |
| public abstract ScriptFunction makeSynchronizedFunction(Object sync); |
| |
| /** |
| * Return the most appropriate invoke handle if there are specializations |
| * @param type most specific method type to look for invocation with |
| * @param args args for trampoline invocation |
| * @return invoke method handle |
| */ |
| private MethodHandle getBestInvoker(final MethodType type, final Object[] args) { |
| return data.getBestInvoker(type, args); |
| } |
| |
| /** |
| * Return the most appropriate invoke handle if there are specializations |
| * @param type most specific method type to look for invocation with |
| * @return invoke method handle |
| */ |
| public MethodHandle getBestInvoker(final MethodType type) { |
| return getBestInvoker(type, null); |
| } |
| |
| /** |
| * Return the invoke handle bound to a given ScriptObject self reference. |
| * If callee parameter is required result is rebound to this. |
| * |
| * @param self self reference |
| * @return bound invoke handle |
| */ |
| public final MethodHandle getBoundInvokeHandle(final Object self) { |
| return MH.bindTo(bindToCalleeIfNeeded(data.getGenericInvoker()), self); |
| } |
| |
| /** |
| * Bind the method handle to this {@code ScriptFunction} instance if it needs a callee parameter. If this function's |
| * method handles don't have a callee parameter, the handle is returned unchanged. |
| * @param methodHandle the method handle to potentially bind to this function instance. |
| * @return the potentially bound method handle |
| */ |
| private MethodHandle bindToCalleeIfNeeded(final MethodHandle methodHandle) { |
| return ScriptFunctionData.needsCallee(methodHandle) ? MH.bindTo(methodHandle, this) : methodHandle; |
| |
| } |
| |
| /** |
| * Get the name for this function |
| * @return the name |
| */ |
| public final String getName() { |
| return data.getName(); |
| } |
| |
| |
| /** |
| * Get the scope for this function |
| * @return the scope |
| */ |
| public final ScriptObject getScope() { |
| return scope; |
| } |
| |
| /** |
| * Prototype getter for this ScriptFunction - follows the naming convention |
| * used by Nasgen and the code generator |
| * |
| * @param self self reference |
| * @return self's prototype |
| */ |
| public static Object G$prototype(final Object self) { |
| return (self instanceof ScriptFunction) ? |
| ((ScriptFunction)self).getPrototype() : |
| UNDEFINED; |
| } |
| |
| /** |
| * Prototype setter for this ScriptFunction - follows the naming convention |
| * used by Nasgen and the code generator |
| * |
| * @param self self reference |
| * @param prototype prototype to set |
| */ |
| public static void S$prototype(final Object self, final Object prototype) { |
| if (self instanceof ScriptFunction) { |
| ((ScriptFunction)self).setPrototype(prototype); |
| } |
| } |
| |
| /** |
| * Length getter - ECMA 15.3.3.2: Function.length |
| * @param self self reference |
| * @return length |
| */ |
| public static int G$length(final Object self) { |
| if (self instanceof ScriptFunction) { |
| return ((ScriptFunction)self).data.getArity(); |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * Name getter - ECMA Function.name |
| * @param self self refence |
| * @return the name, or undefined if none |
| */ |
| public static Object G$name(final Object self) { |
| if (self instanceof ScriptFunction) { |
| return ((ScriptFunction)self).getName(); |
| } |
| |
| return UNDEFINED; |
| } |
| |
| /** |
| * Get the prototype for this ScriptFunction |
| * @param constructor constructor |
| * @return prototype, or null if given constructor is not a ScriptFunction |
| */ |
| public static ScriptObject getPrototype(final Object constructor) { |
| if (constructor instanceof ScriptFunction) { |
| final Object proto = ((ScriptFunction)constructor).getPrototype(); |
| if (proto instanceof ScriptObject) { |
| return (ScriptObject)proto; |
| } |
| } |
| |
| return null; |
| } |
| |
| // These counters are updated only in debug mode. |
| private static int constructorCount; |
| private static int invokes; |
| private static int allocations; |
| |
| /** |
| * @return the constructorCount |
| */ |
| public static int getConstructorCount() { |
| return constructorCount; |
| } |
| |
| /** |
| * @return the invokes |
| */ |
| public static int getInvokes() { |
| return invokes; |
| } |
| |
| /** |
| * @return the allocations |
| */ |
| public static int getAllocations() { |
| return allocations; |
| } |
| |
| @Override |
| protected GuardedInvocation findNewMethod(final CallSiteDescriptor desc) { |
| final MethodType type = desc.getMethodType(); |
| return new GuardedInvocation(pairArguments(data.getBestConstructor(type.changeParameterType(0, ScriptFunction.class), null), type), null, getFunctionGuard(this)); |
| } |
| |
| @SuppressWarnings("unused") |
| private static Object wrapFilter(final Object obj) { |
| if (obj instanceof ScriptObject || !ScriptFunctionData.isPrimitiveThis(obj)) { |
| return obj; |
| } |
| return ((GlobalObject)Context.getGlobalTrusted()).wrapAsObject(obj); |
| } |
| |
| /** |
| * dyn:call call site signature: (callee, thiz, [args...]) |
| * generated method signature: (callee, thiz, [args...]) |
| * |
| * cases: |
| * (a) method has callee parameter |
| * (1) for local/scope calls, we just bind thiz and drop the second argument. |
| * (2) for normal this-calls, we have to swap thiz and callee to get matching signatures. |
| * (b) method doesn't have callee parameter (builtin functions) |
| * (3) for local/scope calls, bind thiz and drop both callee and thiz. |
| * (4) for normal this-calls, drop callee. |
| */ |
| @Override |
| protected GuardedInvocation findCallMethod(final CallSiteDescriptor desc, final LinkRequest request) { |
| final MethodType type = desc.getMethodType(); |
| |
| if (request.isCallSiteUnstable()) { |
| // (this, callee, args...) => (this, callee, args[]) |
| final MethodHandle collector = MH.asCollector(ScriptRuntime.APPLY.methodHandle(), Object[].class, |
| type.parameterCount() - 2); |
| |
| // If call site is statically typed to take a ScriptFunction, we don't need a guard, otherwise we need a |
| // generic "is this a ScriptFunction?" guard. |
| return new GuardedInvocation(collector, ScriptFunction.class.isAssignableFrom(desc.getMethodType().parameterType(0)) |
| ? null : NashornGuards.getScriptFunctionGuard()); |
| } |
| |
| MethodHandle boundHandle; |
| MethodHandle guard = null; |
| |
| final boolean scopeCall = NashornCallSiteDescriptor.isScope(desc); |
| |
| if (data.needsCallee()) { |
| final MethodHandle callHandle = getBestInvoker(type, request.getArguments()); |
| if (scopeCall) { |
| // Make a handle that drops the passed "this" argument and substitutes either Global or Undefined |
| // (callee, this, args...) => (callee, args...) |
| boundHandle = MH.insertArguments(callHandle, 1, needsWrappedThis() ? Context.getGlobalTrusted() : ScriptRuntime.UNDEFINED); |
| // (callee, args...) => (callee, [this], args...) |
| boundHandle = MH.dropArguments(boundHandle, 1, Object.class); |
| |
| } else { |
| // It's already (callee, this, args...), just what we need |
| boundHandle = callHandle; |
| } |
| } else { |
| final MethodHandle callHandle = getBestInvoker(type.dropParameterTypes(0, 1), request.getArguments()); |
| if (data.isBuiltin() && "extend".equals(data.getName())) { |
| // NOTE: the only built-in named "extend" is NativeJava.extend. As a special-case we're binding the |
| // current lookup as its "this" so it can do security-sensitive creation of adapter classes. |
| boundHandle = MH.dropArguments(MH.bindTo(callHandle, desc.getLookup()), 0, Object.class, Object.class); |
| } else if (scopeCall) { |
| // Make a handle that drops the passed "this" argument and substitutes either Global or Undefined |
| // (this, args...) => (args...) |
| boundHandle = MH.bindTo(callHandle, needsWrappedThis() ? Context.getGlobalTrusted() : ScriptRuntime.UNDEFINED); |
| // (args...) => ([callee], [this], args...) |
| boundHandle = MH.dropArguments(boundHandle, 0, Object.class, Object.class); |
| } else { |
| // (this, args...) => ([callee], this, args...) |
| boundHandle = MH.dropArguments(callHandle, 0, Object.class); |
| } |
| } |
| |
| // For non-strict functions, check whether this-object is primitive type. |
| // If so add a to-object-wrapper argument filter. |
| // Else install a guard that will trigger a relink when the argument becomes primitive. |
| if (!scopeCall && needsWrappedThis()) { |
| if (ScriptFunctionData.isPrimitiveThis(request.getArguments()[1])) { |
| boundHandle = MH.filterArguments(boundHandle, 1, WRAPFILTER); |
| } else { |
| guard = getNonStrictFunctionGuard(this); |
| } |
| } |
| |
| boundHandle = pairArguments(boundHandle, type); |
| |
| return new GuardedInvocation(boundHandle, guard == null ? getFunctionGuard(this) : guard); |
| } |
| |
| /** |
| * Used for noSuchMethod/noSuchProperty and JSAdapter hooks. |
| * |
| * These don't want a callee parameter, so bind that. Name binding is optional. |
| */ |
| MethodHandle getCallMethodHandle(final MethodType type, final String bindName) { |
| return pairArguments(bindToNameIfNeeded(bindToCalleeIfNeeded(getBestInvoker(type, null)), bindName), type); |
| } |
| |
| private static MethodHandle bindToNameIfNeeded(final MethodHandle methodHandle, final String bindName) { |
| if (bindName == null) { |
| return methodHandle; |
| } |
| |
| // if it is vararg method, we need to extend argument array with |
| // a new zeroth element that is set to bindName value. |
| final MethodType methodType = methodHandle.type(); |
| final int parameterCount = methodType.parameterCount(); |
| final boolean isVarArg = parameterCount > 0 && methodType.parameterType(parameterCount - 1).isArray(); |
| |
| if (isVarArg) { |
| return MH.filterArguments(methodHandle, 1, MH.insertArguments(ADD_ZEROTH_ELEMENT, 1, bindName)); |
| } |
| return MH.insertArguments(methodHandle, 1, bindName); |
| } |
| |
| /** |
| * Get the guard that checks if a {@link ScriptFunction} is equal to |
| * a known ScriptFunction, using reference comparison |
| * |
| * @param function The ScriptFunction to check against. This will be bound to the guard method handle |
| * |
| * @return method handle for guard |
| */ |
| private static MethodHandle getFunctionGuard(final ScriptFunction function) { |
| assert function.data != null; |
| return MH.insertArguments(IS_FUNCTION_MH, 1, function.data); |
| } |
| |
| /** |
| * Get a guard that checks if a {@link ScriptFunction} is equal to |
| * a known ScriptFunction using reference comparison, and whether the type of |
| * the second argument (this-object) is not a JavaScript primitive type. |
| * |
| * @param function The ScriptFunction to check against. This will be bound to the guard method handle |
| * |
| * @return method handle for guard |
| */ |
| private static MethodHandle getNonStrictFunctionGuard(final ScriptFunction function) { |
| assert function.data != null; |
| return MH.insertArguments(IS_NONSTRICT_FUNCTION, 2, function.data); |
| } |
| |
| @SuppressWarnings("unused") |
| private static boolean isFunctionMH(final Object self, final ScriptFunctionData data) { |
| return self instanceof ScriptFunction && ((ScriptFunction)self).data == data; |
| } |
| |
| @SuppressWarnings("unused") |
| private static boolean isNonStrictFunction(final Object self, final Object arg, final ScriptFunctionData data) { |
| return self instanceof ScriptFunction && ((ScriptFunction)self).data == data && arg instanceof ScriptObject; |
| } |
| |
| @SuppressWarnings("unused") |
| private static Object[] addZerothElement(final Object[] args, final Object value) { |
| // extends input array with by adding new zeroth element |
| final Object[] src = (args == null)? ScriptRuntime.EMPTY_ARRAY : args; |
| final Object[] result = new Object[src.length + 1]; |
| System.arraycopy(src, 0, result, 1, src.length); |
| result[0] = value; |
| return result; |
| } |
| |
| @SuppressWarnings("unused") |
| private static Object invokeSync(final ScriptFunction func, final Object sync, final Object self, final Object... args) |
| throws Throwable { |
| final Object syncObj = sync == UNDEFINED ? self : sync; |
| synchronized (syncObj) { |
| return func.invoke(self, args); |
| } |
| } |
| |
| private static MethodHandle findOwnMH(final String name, final Class<?> rtype, final Class<?>... types) { |
| final Class<?> own = ScriptFunction.class; |
| final MethodType mt = MH.type(rtype, types); |
| try { |
| return MH.findStatic(MethodHandles.lookup(), own, name, mt); |
| } catch (final MethodHandleFactory.LookupException e) { |
| return MH.findVirtual(MethodHandles.lookup(), own, name, mt); |
| } |
| } |
| } |
| |