1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/share/classes/com/sun/tools/javac/jvm/LVTRanges.java Sat Sep 14 19:04:47 2013 +0100
1.3 @@ -0,0 +1,129 @@
1.4 +/*
1.5 + * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
1.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.7 + *
1.8 + * This code is free software; you can redistribute it and/or modify it
1.9 + * under the terms of the GNU General Public License version 2 only, as
1.10 + * published by the Free Software Foundation. Oracle designates this
1.11 + * particular file as subject to the "Classpath" exception as provided
1.12 + * by Oracle in the LICENSE file that accompanied this code.
1.13 + *
1.14 + * This code is distributed in the hope that it will be useful, but WITHOUT
1.15 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.16 + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.17 + * version 2 for more details (a copy is included in the LICENSE file that
1.18 + * accompanied this code).
1.19 + *
1.20 + * You should have received a copy of the GNU General Public License version
1.21 + * 2 along with this work; if not, write to the Free Software Foundation,
1.22 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.23 + *
1.24 + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
1.25 + * or visit www.oracle.com if you need additional information or have any
1.26 + * questions.
1.27 + */
1.28 +
1.29 +package com.sun.tools.javac.jvm;
1.30 +
1.31 +import java.util.Map;
1.32 +import java.util.Map.Entry;
1.33 +import java.util.WeakHashMap;
1.34 +
1.35 +import com.sun.tools.javac.code.Symbol.MethodSymbol;
1.36 +import com.sun.tools.javac.code.Symbol.VarSymbol;
1.37 +import com.sun.tools.javac.tree.JCTree;
1.38 +import com.sun.tools.javac.util.Context;
1.39 +import com.sun.tools.javac.util.List;
1.40 +
1.41 +/** This class contains a one to many relation between a tree and a set of variables.
1.42 + * The relation implies that the given tree closes the DA (definite assignment)
1.43 + * range for the set of variables.
1.44 + *
1.45 + * <p><b>This is NOT part of any supported API.
1.46 + * If you write code that depends on this, you do so at your own risk.
1.47 + * This code and its internal interfaces are subject to change or
1.48 + * deletion without notice.</b>
1.49 + */
1.50 +public class LVTRanges {
1.51 + /** The context key for the LVT ranges. */
1.52 + protected static final Context.Key<LVTRanges> lvtRangesKey = new Context.Key<>();
1.53 +
1.54 + /** Get the LVTRanges instance for this context. */
1.55 + public static LVTRanges instance(Context context) {
1.56 + LVTRanges instance = context.get(lvtRangesKey);
1.57 + if (instance == null) {
1.58 + instance = new LVTRanges(context);
1.59 + }
1.60 + return instance;
1.61 + }
1.62 +
1.63 + private static final long serialVersionUID = 1812267524140424433L;
1.64 +
1.65 + protected Context context;
1.66 +
1.67 + protected Map<MethodSymbol, Map<JCTree, List<VarSymbol>>>
1.68 + aliveRangeClosingTrees = new WeakHashMap<>();
1.69 +
1.70 + public LVTRanges(Context context) {
1.71 + this.context = context;
1.72 + context.put(lvtRangesKey, this);
1.73 + }
1.74 +
1.75 + public List<VarSymbol> getVars(MethodSymbol method, JCTree tree) {
1.76 + Map<JCTree, List<VarSymbol>> varMap = aliveRangeClosingTrees.get(method);
1.77 + return (varMap != null) ? varMap.get(tree) : null;
1.78 + }
1.79 +
1.80 + public boolean containsKey(MethodSymbol method, JCTree tree) {
1.81 + Map<JCTree, List<VarSymbol>> varMap = aliveRangeClosingTrees.get(method);
1.82 + if (varMap == null) {
1.83 + return false;
1.84 + }
1.85 + return varMap.containsKey(tree);
1.86 + }
1.87 +
1.88 + public void setEntry(MethodSymbol method, JCTree tree, List<VarSymbol> vars) {
1.89 + Map<JCTree, List<VarSymbol>> varMap = aliveRangeClosingTrees.get(method);
1.90 + if (varMap != null) {
1.91 + varMap.put(tree, vars);
1.92 + } else {
1.93 + varMap = new WeakHashMap<>();
1.94 + varMap.put(tree, vars);
1.95 + aliveRangeClosingTrees.put(method, varMap);
1.96 + }
1.97 + }
1.98 +
1.99 + public List<VarSymbol> removeEntry(MethodSymbol method, JCTree tree) {
1.100 + Map<JCTree, List<VarSymbol>> varMap = aliveRangeClosingTrees.get(method);
1.101 + if (varMap != null) {
1.102 + List<VarSymbol> result = varMap.remove(tree);
1.103 + if (varMap.isEmpty()) {
1.104 + aliveRangeClosingTrees.remove(method);
1.105 + }
1.106 + return result;
1.107 + }
1.108 + return null;
1.109 + }
1.110 +
1.111 + /* This method should be used for debugging LVT related issues.
1.112 + */
1.113 + @Override
1.114 + public String toString() {
1.115 + String result = "";
1.116 + for (Entry<MethodSymbol, Map<JCTree, List<VarSymbol>>> mainEntry: aliveRangeClosingTrees.entrySet()) {
1.117 + result += "Method: \n" + mainEntry.getKey().flatName() + "\n";
1.118 + int i = 1;
1.119 + for (Entry<JCTree, List<VarSymbol>> treeEntry: mainEntry.getValue().entrySet()) {
1.120 + result += " Tree " + i + ": \n" + treeEntry.getKey().toString() + "\n";
1.121 + result += " Variables closed:\n";
1.122 + for (VarSymbol var: treeEntry.getValue()) {
1.123 + result += " " + var.toString();
1.124 + }
1.125 + result += "\n";
1.126 + i++;
1.127 + }
1.128 + }
1.129 + return result;
1.130 + }
1.131 +
1.132 +}
