| /* |
| * Copyright 2011 Google Inc. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); you may not |
| * use this file except in compliance with the License. You may obtain a copy of |
| * the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT |
| * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the |
| * License for the specific language governing permissions and limitations under |
| * the License. |
| */ |
| package com.google.gwt.dev.jjs.impl; |
| |
| import com.google.gwt.dev.jjs.ast.Context; |
| import com.google.gwt.dev.jjs.ast.JField; |
| import com.google.gwt.dev.jjs.ast.JFieldRef; |
| import com.google.gwt.dev.jjs.ast.JMethod; |
| import com.google.gwt.dev.jjs.ast.JMethodCall; |
| import com.google.gwt.dev.jjs.ast.JModVisitor; |
| import com.google.gwt.dev.jjs.ast.JProgram; |
| import com.google.gwt.dev.jjs.ast.JType; |
| import com.google.gwt.dev.jjs.ast.RuntimeConstants; |
| |
| /** |
| * Prune all overrides of Object.getClass() and inline all method calls to Object.getClass() |
| * as Object.___clazz. |
| * <p> |
| * The Devirtualizer pass needs to run before this pass. |
| */ |
| public class ReplaceGetClassOverrides { |
| public static void exec(JProgram program) { |
| new GetClassInlinerRemover(program).accept(program); |
| } |
| |
| private static class GetClassInlinerRemover extends JModVisitor { |
| |
| private JProgram program; |
| private JMethod getClassMethod; |
| private JField clazzField; |
| |
| public GetClassInlinerRemover(JProgram program) { |
| this.program = program; |
| getClassMethod = program.getIndexedMethod(RuntimeConstants.OBJECT_GET_CLASS); |
| clazzField = program.getIndexedField(RuntimeConstants.OBJECT_CLAZZ); |
| } |
| |
| @Override |
| public void endVisit(JMethod x, Context ctx) { |
| if (!isGetClassMethod(x)) { |
| return; |
| } |
| |
| if (x.getEnclosingType() == program.getTypeJavaLangObject()) { |
| // Remove all overrides but keep the method in java.lang.Object as references from JSNI |
| // are not removed. |
| x.getOverridingMethods().clear(); |
| return; |
| } |
| ctx.removeMe(); |
| } |
| |
| @Override |
| public void endVisit(JMethodCall x, Context ctx) { |
| |
| // All calls to getClass with reference to Object.clazz field |
| if (isGetClassMethod(x.getTarget())) { |
| assert !isGetClassDevirtualized(x.getTarget().getEnclosingType()); |
| ctx.replaceMe(new JFieldRef(x.getSourceInfo(), x.getInstance(), |
| clazzField, clazzField.getEnclosingType())); |
| } |
| } |
| |
| private boolean isGetClassMethod(JMethod method) { |
| return method == getClassMethod || method.getOverriddenMethods().contains(getClassMethod); |
| } |
| |
| private boolean isGetClassDevirtualized(JType type) { |
| return type == program.getJavaScriptObject() |
| || program.getRepresentedAsNativeTypes().contains(type) |
| || type.isJsNative(); |
| } |
| } |
| } |