1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/rt/vm/src/main/java/org/apidesign/vm4brwsr/LocalsMapper.java Tue Feb 26 16:54:16 2013 +0100
1.3 @@ -0,0 +1,142 @@
1.4 +/**
1.5 + * Back 2 Browser Bytecode Translator
1.6 + * Copyright (C) 2012 Jaroslav Tulach <jaroslav.tulach@apidesign.org>
1.7 + *
1.8 + * This program is free software: you can redistribute it and/or modify
1.9 + * it under the terms of the GNU General Public License as published by
1.10 + * the Free Software Foundation, version 2 of the License.
1.11 + *
1.12 + * This program is distributed in the hope that it will be useful,
1.13 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
1.14 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
1.15 + * GNU General Public License for more details.
1.16 + *
1.17 + * You should have received a copy of the GNU General Public License
1.18 + * along with this program. Look for COPYING file in the top folder.
1.19 + * If not, see http://opensource.org/licenses/GPL-2.0.
1.20 + */
1.21 +package org.apidesign.vm4brwsr;
1.22 +
1.23 +import java.io.IOException;
1.24 +import org.apidesign.javap.RuntimeConstants;
1.25 +import org.apidesign.javap.TypeArray;
1.26 +
1.27 +final class LocalsMapper {
1.28 + private final TypeArray argTypeRecords;
1.29 + private final TypeArray localTypeRecords;
1.30 +
1.31 + public LocalsMapper(final TypeArray stackMapArgs) {
1.32 + final TypeArray initTypeRecords = new TypeArray();
1.33 + updateRecords(initTypeRecords, stackMapArgs);
1.34 +
1.35 + argTypeRecords = initTypeRecords;
1.36 + localTypeRecords = new TypeArray(initTypeRecords);
1.37 + }
1.38 +
1.39 + public void outputArguments(final Appendable out, boolean isStatic) throws IOException {
1.40 + final int argRecordCount = argTypeRecords.getSize();
1.41 + int first = isStatic ? 0 : 1;
1.42 + if (argRecordCount > first) {
1.43 + Variable variable = getVariable(argTypeRecords, first);
1.44 + out.append(variable);
1.45 +
1.46 + int i = first + (variable.isCategory2() ? 2 : 1);
1.47 + while (i < argRecordCount) {
1.48 + variable = getVariable(argTypeRecords, i);
1.49 + out.append(", ");
1.50 + out.append(variable);
1.51 + i += variable.isCategory2() ? 2 : 1;
1.52 + }
1.53 + }
1.54 + }
1.55 +
1.56 + public void syncWithFrameLocals(final TypeArray frameLocals) {
1.57 + updateRecords(localTypeRecords, frameLocals);
1.58 + }
1.59 +
1.60 + public Variable setI(final int index) {
1.61 + return setT(index, VarType.INTEGER);
1.62 + }
1.63 +
1.64 + public Variable setL(final int index) {
1.65 + return setT(index, VarType.LONG);
1.66 + }
1.67 +
1.68 + public Variable setF(final int index) {
1.69 + return setT(index, VarType.FLOAT);
1.70 + }
1.71 +
1.72 + public Variable setD(final int index) {
1.73 + return setT(index, VarType.DOUBLE);
1.74 + }
1.75 +
1.76 + public Variable setA(final int index) {
1.77 + return setT(index, VarType.REFERENCE);
1.78 + }
1.79 +
1.80 + public Variable setT(final int index, final int type) {
1.81 + updateRecord(localTypeRecords, index, type);
1.82 + return Variable.getLocalVariable(type, index);
1.83 + }
1.84 +
1.85 + public Variable getI(final int index) {
1.86 + return getT(index, VarType.INTEGER);
1.87 + }
1.88 +
1.89 + public Variable getL(final int index) {
1.90 + return getT(index, VarType.LONG);
1.91 + }
1.92 +
1.93 + public Variable getF(final int index) {
1.94 + return getT(index, VarType.FLOAT);
1.95 + }
1.96 +
1.97 + public Variable getD(final int index) {
1.98 + return getT(index, VarType.DOUBLE);
1.99 + }
1.100 +
1.101 + public Variable getA(final int index) {
1.102 + return getT(index, VarType.REFERENCE);
1.103 + }
1.104 +
1.105 + public Variable getT(final int index, final int type) {
1.106 + final int oldRecordValue = localTypeRecords.get(index);
1.107 + if ((oldRecordValue & 0xff) != type) {
1.108 + throw new IllegalStateException("Type mismatch");
1.109 + }
1.110 +
1.111 + return Variable.getLocalVariable(type, index);
1.112 + }
1.113 +
1.114 + private static void updateRecords(final TypeArray typeRecords,
1.115 + final TypeArray stackMapTypes) {
1.116 + final int srcSize = stackMapTypes.getSize();
1.117 + for (int i = 0, dstIndex = 0; i < srcSize; ++i) {
1.118 + final int smType = stackMapTypes.get(i);
1.119 + if (smType == RuntimeConstants.ITEM_Bogus) {
1.120 + ++dstIndex;
1.121 + continue;
1.122 + }
1.123 + final int varType = VarType.fromStackMapType(smType);
1.124 + updateRecord(typeRecords, dstIndex, varType);
1.125 + dstIndex += VarType.isCategory2(varType) ? 2 : 1;
1.126 + }
1.127 + }
1.128 +
1.129 + private static void updateRecord(final TypeArray typeRecords,
1.130 + final int index, final int type) {
1.131 + if (typeRecords.getSize() < (index + 1)) {
1.132 + typeRecords.setSize(index + 1);
1.133 + }
1.134 +
1.135 + final int oldRecordValue = typeRecords.get(index);
1.136 + final int usedTypesMask =
1.137 + (oldRecordValue >> 8) | (1 << type);
1.138 + typeRecords.set(index, (usedTypesMask << 8) | type);
1.139 + }
1.140 +
1.141 + private static Variable getVariable(final TypeArray typeRecords,
1.142 + final int index) {
1.143 + return Variable.getLocalVariable(typeRecords.get(index) & 0xff, index);
1.144 + }
1.145 +}