1.1 --- a/vm/src/main/java/org/apidesign/vm4brwsr/StackMapper.java Mon Feb 25 19:00:08 2013 +0100
1.2 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000
1.3 @@ -1,194 +0,0 @@
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 org.apidesign.javap.TypeArray;
1.24 -
1.25 -final class StackMapper {
1.26 - private final TypeArray stackTypeIndexPairs;
1.27 - private int[] typeCounters;
1.28 - private int[] typeMaxCounters;
1.29 -
1.30 - public StackMapper() {
1.31 - stackTypeIndexPairs = new TypeArray();
1.32 - typeCounters = new int[VarType.LAST + 1];
1.33 - typeMaxCounters = new int[VarType.LAST + 1];
1.34 - }
1.35 -
1.36 - public void clear() {
1.37 - for (int type = 0; type <= VarType.LAST; ++type) {
1.38 - typeCounters[type] = 0;
1.39 - }
1.40 - stackTypeIndexPairs.clear();
1.41 - }
1.42 -
1.43 - public void syncWithFrameStack(final TypeArray frameStack) {
1.44 - clear();
1.45 -
1.46 - final int size = frameStack.getSize();
1.47 - for (int i = 0; i < size; ++i) {
1.48 - pushTypeImpl(VarType.fromStackMapType(frameStack.get(i)));
1.49 - }
1.50 - }
1.51 -
1.52 - public Variable pushI() {
1.53 - return pushT(VarType.INTEGER);
1.54 - }
1.55 -
1.56 - public Variable pushL() {
1.57 - return pushT(VarType.LONG);
1.58 - }
1.59 -
1.60 - public Variable pushF() {
1.61 - return pushT(VarType.FLOAT);
1.62 - }
1.63 -
1.64 - public Variable pushD() {
1.65 - return pushT(VarType.DOUBLE);
1.66 - }
1.67 -
1.68 - public Variable pushA() {
1.69 - return pushT(VarType.REFERENCE);
1.70 - }
1.71 -
1.72 - public Variable pushT(final int type) {
1.73 - return getVariable(pushTypeImpl(type));
1.74 - }
1.75 -
1.76 - public Variable popI() {
1.77 - return popT(VarType.INTEGER);
1.78 - }
1.79 -
1.80 - public Variable popL() {
1.81 - return popT(VarType.LONG);
1.82 - }
1.83 -
1.84 - public Variable popF() {
1.85 - return popT(VarType.FLOAT);
1.86 - }
1.87 -
1.88 - public Variable popD() {
1.89 - return popT(VarType.DOUBLE);
1.90 - }
1.91 -
1.92 - public Variable popA() {
1.93 - return popT(VarType.REFERENCE);
1.94 - }
1.95 -
1.96 - public Variable popT(final int type) {
1.97 - final Variable variable = getT(0, type);
1.98 - popImpl(1);
1.99 - return variable;
1.100 - }
1.101 -
1.102 - public Variable pop() {
1.103 - final Variable variable = get(0);
1.104 - popImpl(1);
1.105 - return variable;
1.106 - }
1.107 -
1.108 - public void pop(final int count) {
1.109 - final int stackSize = stackTypeIndexPairs.getSize();
1.110 - if (count > stackSize) {
1.111 - throw new IllegalStateException("Stack underflow");
1.112 - }
1.113 - popImpl(count);
1.114 - }
1.115 -
1.116 - public Variable getI(final int indexFromTop) {
1.117 - return getT(indexFromTop, VarType.INTEGER);
1.118 - }
1.119 -
1.120 - public Variable getL(final int indexFromTop) {
1.121 - return getT(indexFromTop, VarType.LONG);
1.122 - }
1.123 -
1.124 - public Variable getF(final int indexFromTop) {
1.125 - return getT(indexFromTop, VarType.FLOAT);
1.126 - }
1.127 -
1.128 - public Variable getD(final int indexFromTop) {
1.129 - return getT(indexFromTop, VarType.DOUBLE);
1.130 - }
1.131 -
1.132 - public Variable getA(final int indexFromTop) {
1.133 - return getT(indexFromTop, VarType.REFERENCE);
1.134 - }
1.135 -
1.136 - public Variable getT(final int indexFromTop, final int type) {
1.137 - final int stackSize = stackTypeIndexPairs.getSize();
1.138 - if (indexFromTop >= stackSize) {
1.139 - throw new IllegalStateException("Stack underflow");
1.140 - }
1.141 - final int stackValue =
1.142 - stackTypeIndexPairs.get(stackSize - indexFromTop - 1);
1.143 - if ((stackValue & 0xff) != type) {
1.144 - throw new IllegalStateException("Type mismatch");
1.145 - }
1.146 -
1.147 - return getVariable(stackValue);
1.148 - }
1.149 -
1.150 - public Variable get(final int indexFromTop) {
1.151 - final int stackSize = stackTypeIndexPairs.getSize();
1.152 - if (indexFromTop >= stackSize) {
1.153 - throw new IllegalStateException("Stack underflow");
1.154 - }
1.155 - final int stackValue =
1.156 - stackTypeIndexPairs.get(stackSize - indexFromTop - 1);
1.157 -
1.158 - return getVariable(stackValue);
1.159 - }
1.160 -
1.161 - private int pushTypeImpl(final int type) {
1.162 - final int count = typeCounters[type];
1.163 - final int value = (count << 8) | (type & 0xff);
1.164 - incCounter(type);
1.165 - stackTypeIndexPairs.add(value);
1.166 -
1.167 - return value;
1.168 - }
1.169 -
1.170 - private void popImpl(final int count) {
1.171 - final int stackSize = stackTypeIndexPairs.getSize();
1.172 - for (int i = stackSize - count; i < stackSize; ++i) {
1.173 - final int value = stackTypeIndexPairs.get(i);
1.174 - decCounter(value & 0xff);
1.175 - }
1.176 -
1.177 - stackTypeIndexPairs.setSize(stackSize - count);
1.178 - }
1.179 -
1.180 - private void incCounter(final int type) {
1.181 - final int newValue = ++typeCounters[type];
1.182 - if (typeMaxCounters[type] < newValue) {
1.183 - typeMaxCounters[type] = newValue;
1.184 - }
1.185 - }
1.186 -
1.187 - private void decCounter(final int type) {
1.188 - --typeCounters[type];
1.189 - }
1.190 -
1.191 - public Variable getVariable(final int typeAndIndex) {
1.192 - final int type = typeAndIndex & 0xff;
1.193 - final int index = typeAndIndex >> 8;
1.194 -
1.195 - return Variable.getStackVariable(type, index);
1.196 - }
1.197 -}