lubomir@319: /**
lubomir@319:  * Back 2 Browser Bytecode Translator
lubomir@319:  * Copyright (C) 2012 Jaroslav Tulach <jaroslav.tulach@apidesign.org>
lubomir@319:  *
lubomir@319:  * This program is free software: you can redistribute it and/or modify
lubomir@319:  * it under the terms of the GNU General Public License as published by
lubomir@319:  * the Free Software Foundation, version 2 of the License.
lubomir@319:  *
lubomir@319:  * This program is distributed in the hope that it will be useful,
lubomir@319:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
lubomir@319:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
lubomir@319:  * GNU General Public License for more details.
lubomir@319:  *
lubomir@319:  * You should have received a copy of the GNU General Public License
lubomir@319:  * along with this program. Look for COPYING file in the top folder.
lubomir@319:  * If not, see http://opensource.org/licenses/GPL-2.0.
lubomir@319:  */
lubomir@319: package org.apidesign.vm4brwsr;
lubomir@319: 
lubomir@319: import java.io.IOException;
lubomir@319: import org.apidesign.javap.RuntimeConstants;
lubomir@319: import org.apidesign.javap.TypeArray;
lubomir@319: 
lubomir@319: final class LocalsMapper {
lubomir@319:     private final TypeArray argTypeRecords;
lubomir@319:     private final TypeArray localTypeRecords;
lubomir@319: 
lubomir@319:     public LocalsMapper(final TypeArray stackMapArgs) {
lubomir@319:         final TypeArray initTypeRecords = new TypeArray();
lubomir@319:         updateRecords(initTypeRecords, stackMapArgs);
lubomir@319: 
lubomir@319:         argTypeRecords = initTypeRecords;
lubomir@319:         localTypeRecords = new TypeArray(initTypeRecords);
lubomir@319:     }
lubomir@319: 
jaroslav@442:     public void outputArguments(final Appendable out, boolean isStatic) throws IOException {
lubomir@319:         final int argRecordCount = argTypeRecords.getSize();
jaroslav@442:         int first = isStatic ? 0 : 1;
jaroslav@442:         if (argRecordCount > first) {
jaroslav@442:             Variable variable = getVariable(argTypeRecords, first);
lubomir@319:             out.append(variable);
lubomir@319: 
jaroslav@442:             int i = first + (variable.isCategory2() ? 2 : 1);
lubomir@319:             while (i < argRecordCount) {
lubomir@319:                 variable = getVariable(argTypeRecords, i);
lubomir@319:                 out.append(", ");
lubomir@319:                 out.append(variable);
lubomir@319:                 i += variable.isCategory2() ? 2 : 1;
lubomir@319:             }
lubomir@319:         }
lubomir@319:     }
lubomir@319: 
lubomir@319:     public void syncWithFrameLocals(final TypeArray frameLocals) {
lubomir@319:         updateRecords(localTypeRecords, frameLocals);
lubomir@319:     }
lubomir@319: 
lubomir@319:     public Variable setI(final int index) {
lubomir@319:         return setT(index, VarType.INTEGER);
lubomir@319:     }
lubomir@319: 
lubomir@319:     public Variable setL(final int index) {
lubomir@319:         return setT(index, VarType.LONG);
lubomir@319:     }
lubomir@319: 
lubomir@319:     public Variable setF(final int index) {
lubomir@319:         return setT(index, VarType.FLOAT);
lubomir@319:     }
lubomir@319: 
lubomir@319:     public Variable setD(final int index) {
lubomir@319:         return setT(index, VarType.DOUBLE);
lubomir@319:     }
lubomir@319: 
lubomir@319:     public Variable setA(final int index) {
lubomir@319:         return setT(index, VarType.REFERENCE);
lubomir@319:     }
lubomir@319: 
lubomir@319:     public Variable setT(final int index, final int type) {
lubomir@319:         updateRecord(localTypeRecords, index, type);
lubomir@319:         return Variable.getLocalVariable(type, index);
lubomir@319:     }
lubomir@319: 
lubomir@319:     public Variable getI(final int index) {
lubomir@319:         return getT(index, VarType.INTEGER);
lubomir@319:     }
lubomir@319: 
lubomir@319:     public Variable getL(final int index) {
lubomir@319:         return getT(index, VarType.LONG);
lubomir@319:     }
lubomir@319: 
lubomir@319:     public Variable getF(final int index) {
lubomir@319:         return getT(index, VarType.FLOAT);
lubomir@319:     }
lubomir@319: 
lubomir@319:     public Variable getD(final int index) {
lubomir@319:         return getT(index, VarType.DOUBLE);
lubomir@319:     }
lubomir@319: 
lubomir@319:     public Variable getA(final int index) {
lubomir@319:         return getT(index, VarType.REFERENCE);
lubomir@319:     }
lubomir@319: 
lubomir@319:     public Variable getT(final int index, final int type) {
lubomir@319:         final int oldRecordValue = localTypeRecords.get(index);
lubomir@319:         if ((oldRecordValue & 0xff) != type) {
lubomir@319:             throw new IllegalStateException("Type mismatch");
lubomir@319:         }
lubomir@319: 
lubomir@319:         return Variable.getLocalVariable(type, index);
lubomir@319:     }
lubomir@319: 
lubomir@319:     private static void updateRecords(final TypeArray typeRecords,
lubomir@319:                                       final TypeArray stackMapTypes) {
lubomir@319:         final int srcSize = stackMapTypes.getSize();
lubomir@319:         for (int i = 0, dstIndex = 0; i < srcSize; ++i) {
lubomir@319:             final int smType = stackMapTypes.get(i);
lubomir@319:             if (smType == RuntimeConstants.ITEM_Bogus) {
lubomir@319:                 ++dstIndex;
lubomir@319:                 continue;
lubomir@319:             }
lubomir@319:             final int varType = VarType.fromStackMapType(smType);
lubomir@319:             updateRecord(typeRecords, dstIndex, varType);
lubomir@319:             dstIndex += VarType.isCategory2(varType) ? 2 : 1;
lubomir@319:         }
lubomir@319:     }
lubomir@319: 
lubomir@319:     private static void updateRecord(final TypeArray typeRecords,
lubomir@319:                                      final int index, final int type) {
lubomir@319:         if (typeRecords.getSize() < (index + 1)) {
lubomir@319:             typeRecords.setSize(index + 1);
lubomir@319:         }
lubomir@319: 
lubomir@319:         final int oldRecordValue = typeRecords.get(index);
lubomir@319:         final int usedTypesMask =
lubomir@319:                 (oldRecordValue >> 8) | (1 << type);
lubomir@319:         typeRecords.set(index, (usedTypesMask << 8) | type);
lubomir@319:     }
lubomir@319: 
lubomir@319:     private static Variable getVariable(final TypeArray typeRecords,
lubomir@319:                                         final int index) {
lubomir@319:         return Variable.getLocalVariable(typeRecords.get(index) & 0xff, index);
lubomir@319:     }
lubomir@319: }