| /* |
| * 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 java.lang.invoke.MethodHandle; |
| import java.lang.invoke.MethodType; |
| import java.util.Collection; |
| import java.util.List; |
| |
| /** |
| * This is a subclass that represents a script function that may not be regenerated. |
| * This is used for example for bound functions and builtins. |
| */ |
| final class FinalScriptFunctionData extends ScriptFunctionData { |
| |
| private static final long serialVersionUID = -930632846167768864L; |
| |
| /** |
| * Constructor - used for bind |
| * |
| * @param name name |
| * @param arity arity |
| * @param functions precompiled code |
| * @param flags {@link ScriptFunctionData} flags |
| */ |
| FinalScriptFunctionData(final String name, final int arity, final List<CompiledFunction> functions, final int flags) { |
| super(name, arity, flags); |
| code.addAll(functions); |
| assert !needsCallee(); |
| } |
| |
| /** |
| * Constructor - used from ScriptFunction. This assumes that we have code already for the |
| * method (typically a native method) and possibly specializations. |
| * |
| * @param name name |
| * @param mh method handle for generic version of method |
| * @param specs specializations |
| * @param flags {@link ScriptFunctionData} flags |
| */ |
| FinalScriptFunctionData(final String name, final MethodHandle mh, final Specialization[] specs, final int flags) { |
| super(name, methodHandleArity(mh), flags); |
| |
| addInvoker(mh); |
| if (specs != null) { |
| for (final Specialization spec : specs) { |
| addInvoker(spec.getMethodHandle(), spec); |
| } |
| } |
| } |
| |
| @Override |
| protected boolean needsCallee() { |
| final boolean needsCallee = code.getFirst().needsCallee(); |
| assert allNeedCallee(needsCallee); |
| return needsCallee; |
| } |
| |
| private boolean allNeedCallee(final boolean needCallee) { |
| for (final CompiledFunction inv : code) { |
| if(inv.needsCallee() != needCallee) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| @Override |
| CompiledFunction getBest(final MethodType callSiteType, final ScriptObject runtimeScope, final Collection<CompiledFunction> forbidden) { |
| assert isValidCallSite(callSiteType) : callSiteType; |
| |
| CompiledFunction best = null; |
| for (final CompiledFunction candidate: code) { |
| if (!forbidden.contains(candidate) && candidate.betterThanFinal(best, callSiteType)) { |
| best = candidate; |
| } |
| } |
| |
| return best; |
| } |
| |
| @Override |
| MethodType getGenericType() { |
| // We need to ask the code for its generic type. We can't just rely on this function data's arity, as it's not |
| // actually correct for lots of built-ins. E.g. ECMAScript 5.1 section 15.5.3.2 prescribes that |
| // Script.fromCharCode([char0[, char1[, ...]]]) has a declared arity of 1 even though it's a variable arity |
| // method. |
| int max = 0; |
| for(final CompiledFunction fn: code) { |
| final MethodType t = fn.type(); |
| if(ScriptFunctionData.isVarArg(t)) { |
| // 2 for (callee, this, args[]) |
| return MethodType.genericMethodType(2, true); |
| } |
| final int paramCount = t.parameterCount() - (ScriptFunctionData.needsCallee(t) ? 1 : 0); |
| if(paramCount > max) { |
| max = paramCount; |
| } |
| } |
| // +1 for callee |
| return MethodType.genericMethodType(max + 1); |
| } |
| |
| private CompiledFunction addInvoker(final MethodHandle mh, final Specialization specialization) { |
| assert !needsCallee(mh); |
| |
| final CompiledFunction invoker; |
| if (isConstructor(mh)) { |
| // only nasgen constructors: (boolean, self, args) are subject to binding a boolean newObj. isConstructor |
| // is too conservative a check. However, isConstructor(mh) always implies isConstructor param |
| assert isConstructor(); |
| invoker = CompiledFunction.createBuiltInConstructor(mh); |
| } else { |
| invoker = new CompiledFunction(mh, null, specialization); |
| } |
| code.add(invoker); |
| |
| return invoker; |
| } |
| |
| private CompiledFunction addInvoker(final MethodHandle mh) { |
| return addInvoker(mh, null); |
| } |
| |
| private static int methodHandleArity(final MethodHandle mh) { |
| if (isVarArg(mh)) { |
| return MAX_ARITY; |
| } |
| |
| //drop self, callee and boolean constructor flag to get real arity |
| return mh.type().parameterCount() - 1 - (needsCallee(mh) ? 1 : 0) - (isConstructor(mh) ? 1 : 0); |
| } |
| |
| private static boolean isConstructor(final MethodHandle mh) { |
| return mh.type().parameterCount() >= 1 && mh.type().parameterType(0) == boolean.class; |
| } |
| |
| } |