lubomir@221: /**
lubomir@221:  * Back 2 Browser Bytecode Translator
lubomir@221:  * Copyright (C) 2012 Jaroslav Tulach <jaroslav.tulach@apidesign.org>
lubomir@221:  *
lubomir@221:  * This program is free software: you can redistribute it and/or modify
lubomir@221:  * it under the terms of the GNU General Public License as published by
lubomir@221:  * the Free Software Foundation, version 2 of the License.
lubomir@221:  *
lubomir@221:  * This program is distributed in the hope that it will be useful,
lubomir@221:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
lubomir@221:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
lubomir@221:  * GNU General Public License for more details.
lubomir@221:  *
lubomir@221:  * You should have received a copy of the GNU General Public License
lubomir@221:  * along with this program. Look for COPYING file in the top folder.
lubomir@221:  * If not, see http://opensource.org/licenses/GPL-2.0.
lubomir@221:  */
lubomir@221: package org.apidesign.vm4brwsr;
lubomir@221: 
jaroslav@1453: import java.io.IOException;
jaroslav@810: import org.apidesign.vm4brwsr.ByteCodeParser.TypeArray;
lubomir@281: 
lubomir@310: final class StackMapper {
lubomir@281:     private final TypeArray stackTypeIndexPairs;
jaroslav@1455:     private final StringArray stackValues;
lubomir@221: 
lubomir@307:     public StackMapper() {
lubomir@281:         stackTypeIndexPairs = new TypeArray();
jaroslav@1455:         stackValues = new StringArray();
lubomir@221:     }
lubomir@221: 
lubomir@281:     public void clear() {
lubomir@281:         stackTypeIndexPairs.clear();
jaroslav@1455:         stackValues.clear();
lubomir@281:     }
lubomir@281: 
lubomir@281:     public void syncWithFrameStack(final TypeArray frameStack) {
lubomir@281:         clear();
lubomir@281: 
lubomir@281:         final int size = frameStack.getSize();
lubomir@281:         for (int i = 0; i < size; ++i) {
lubomir@307:             pushTypeImpl(VarType.fromStackMapType(frameStack.get(i)));
lubomir@221:         }
lubomir@221:     }
lubomir@221: 
lubomir@281:     public Variable pushI() {
lubomir@307:         return pushT(VarType.INTEGER);
lubomir@281:     }
lubomir@281: 
lubomir@281:     public Variable pushL() {
lubomir@307:         return pushT(VarType.LONG);
lubomir@281:     }
lubomir@281: 
lubomir@281:     public Variable pushF() {
lubomir@307:         return pushT(VarType.FLOAT);
lubomir@281:     }
lubomir@281: 
lubomir@281:     public Variable pushD() {
lubomir@307:         return pushT(VarType.DOUBLE);
lubomir@281:     }
lubomir@281: 
lubomir@281:     public Variable pushA() {
lubomir@307:         return pushT(VarType.REFERENCE);
lubomir@281:     }
lubomir@281: 
lubomir@281:     public Variable pushT(final int type) {
lubomir@281:         return getVariable(pushTypeImpl(type));
lubomir@281:     }
lubomir@281: 
jaroslav@1453:     void assign(Appendable out, int varType, CharSequence s) throws IOException {
jaroslav@1455:         pushTypeAndValue(varType, s);
jaroslav@1457:     }
jaroslav@1457: 
jaroslav@1457:     void replace(Appendable out, int varType, String format, CharSequence... arr) 
jaroslav@1457:     throws IOException {
jaroslav@1457:         StringBuilder sb = new StringBuilder();
jaroslav@1457:         ByteCodeToJavaScript.emitImpl(sb, format, arr);
jaroslav@1457:         String[] values = stackValues.toArray();
jaroslav@1457:         final int last = stackTypeIndexPairs.getSize() - 1;
jaroslav@1457:         values[last] = sb.toString();
jaroslav@1457:         stackTypeIndexPairs.set(last, varType);
jaroslav@1455:     }
jaroslav@1455:     
jaroslav@1455:     void flush(Appendable out) throws IOException {
jaroslav@1455:         int count = stackTypeIndexPairs.getSize();
jaroslav@1455:         for (int i = 0; i < count; i++) {
jaroslav@1466:             String val = stackValues.getAndClear(i, true);
jaroslav@1455:             if (val == null) {
jaroslav@1455:                 continue;
jaroslav@1455:             }
jaroslav@1455:             CharSequence var = getVariable(stackTypeIndexPairs.get(i));
jaroslav@1455:             ByteCodeToJavaScript.emitImpl(out, "var @1 = @2;", var, val);
jaroslav@1455:         }
jaroslav@1453:     }
jaroslav@1453:     
jaroslav@1457:     public CharSequence popI() {
lubomir@307:         return popT(VarType.INTEGER);
lubomir@281:     }
lubomir@281: 
jaroslav@1457:     public CharSequence popL() {
lubomir@307:         return popT(VarType.LONG);
lubomir@281:     }
lubomir@281: 
jaroslav@1457:     public CharSequence popF() {
lubomir@307:         return popT(VarType.FLOAT);
lubomir@281:     }
lubomir@281: 
jaroslav@1457:     public CharSequence popD() {
lubomir@307:         return popT(VarType.DOUBLE);
lubomir@281:     }
lubomir@281: 
jaroslav@1457:     public CharSequence popA() {
lubomir@307:         return popT(VarType.REFERENCE);
lubomir@281:     }
lubomir@281: 
jaroslav@1457:     public CharSequence popT(final int type) {
jaroslav@1457:         final CharSequence variable = getT(0, type);
lubomir@281:         popImpl(1);
lubomir@281:         return variable;
lubomir@281:     }
lubomir@281: 
jaroslav@1457:     public CharSequence popValue() {
jaroslav@1457:         final CharSequence variable = getT(0, -1);
jaroslav@1457:         popImpl(1);
jaroslav@1457:         return variable;
jaroslav@1457:     }
jaroslav@1457:     public Variable pop(Appendable out) throws IOException {
jaroslav@1457:         flush(out);
lubomir@281:         final Variable variable = get(0);
lubomir@281:         popImpl(1);
lubomir@281:         return variable;
lubomir@281:     }
lubomir@281: 
lubomir@281:     public void pop(final int count) {
lubomir@281:         final int stackSize = stackTypeIndexPairs.getSize();
lubomir@281:         if (count > stackSize) {
lubomir@281:             throw new IllegalStateException("Stack underflow");
lubomir@281:         }
lubomir@281:         popImpl(count);
lubomir@281:     }
lubomir@281: 
jaroslav@1457:     public CharSequence getI(final int indexFromTop) {
lubomir@307:         return getT(indexFromTop, VarType.INTEGER);
lubomir@281:     }
lubomir@281: 
jaroslav@1457:     public CharSequence getL(final int indexFromTop) {
lubomir@307:         return getT(indexFromTop, VarType.LONG);
lubomir@281:     }
lubomir@281: 
jaroslav@1457:     public CharSequence getF(final int indexFromTop) {
lubomir@307:         return getT(indexFromTop, VarType.FLOAT);
lubomir@281:     }
lubomir@281: 
jaroslav@1457:     public CharSequence getD(final int indexFromTop) {
lubomir@307:         return getT(indexFromTop, VarType.DOUBLE);
lubomir@281:     }
lubomir@281: 
jaroslav@1457:     public CharSequence getA(final int indexFromTop) {
lubomir@307:         return getT(indexFromTop, VarType.REFERENCE);
lubomir@281:     }
lubomir@281: 
jaroslav@1457:     public CharSequence getT(final int indexFromTop, final int type) {
jaroslav@1466:         return getT(indexFromTop, type, true);
jaroslav@1466:     }
jaroslav@1466:     public CharSequence getT(final int indexFromTop, final int type, boolean clear) {
lubomir@281:         final int stackSize = stackTypeIndexPairs.getSize();
lubomir@281:         if (indexFromTop >= stackSize) {
lubomir@281:             throw new IllegalStateException("Stack underflow");
lubomir@281:         }
lubomir@281:         final int stackValue =
lubomir@281:                 stackTypeIndexPairs.get(stackSize - indexFromTop - 1);
jaroslav@1457:         if (type != -1 && (stackValue & 0xff) != type) {
lubomir@281:             throw new IllegalStateException("Type mismatch");
lubomir@281:         }
jaroslav@1457:         String value =
jaroslav@1466:             stackValues.getAndClear(stackSize - indexFromTop - 1, clear);
jaroslav@1457:         if (value != null) {
jaroslav@1457:             return value;
jaroslav@1457:         }
lubomir@281:         return getVariable(stackValue);
lubomir@281:     }
lubomir@281: 
lubomir@281:     public Variable get(final int indexFromTop) {
lubomir@281:         final int stackSize = stackTypeIndexPairs.getSize();
lubomir@281:         if (indexFromTop >= stackSize) {
lubomir@281:             throw new IllegalStateException("Stack underflow");
lubomir@281:         }
lubomir@281:         final int stackValue =
lubomir@281:                 stackTypeIndexPairs.get(stackSize - indexFromTop - 1);
lubomir@281: 
lubomir@281:         return getVariable(stackValue);
lubomir@281:     }
lubomir@281: 
lubomir@281:     private int pushTypeImpl(final int type) {
jaroslav@1454:         final int count = stackTypeIndexPairs.getSize();
lubomir@281:         final int value = (count << 8) | (type & 0xff);
lubomir@281:         stackTypeIndexPairs.add(value);
jaroslav@1455:         
jaroslav@1455:         addStackValue(count, null);
jaroslav@1455:         return value;
jaroslav@1455:     }
lubomir@281: 
jaroslav@1455:     private void pushTypeAndValue(final int type, CharSequence v) {
jaroslav@1455:         final int count = stackTypeIndexPairs.getSize();
jaroslav@1455:         final int value = (count << 8) | (type & 0xff);
jaroslav@1455:         stackTypeIndexPairs.add(value);
jaroslav@1455:         final String val = v.toString();
jaroslav@1455:         addStackValue(count, val);
jaroslav@1455:     }
jaroslav@1455: 
jaroslav@1455:     private void addStackValue(int at, final String val) {
jaroslav@1455:         final String[] arr = stackValues.toArray();
jaroslav@1455:         if (arr.length > at) {
jaroslav@1455:             arr[at] = val;
jaroslav@1455:         } else {
jaroslav@1455:             stackValues.add(val);
jaroslav@1455:         }
lubomir@281:     }
lubomir@281: 
lubomir@281:     private void popImpl(final int count) {
lubomir@281:         final int stackSize = stackTypeIndexPairs.getSize();
lubomir@281:         stackTypeIndexPairs.setSize(stackSize - count);
lubomir@281:     }
lubomir@281: 
lubomir@281:     public Variable getVariable(final int typeAndIndex) {
lubomir@281:         final int type = typeAndIndex & 0xff;
lubomir@281:         final int index = typeAndIndex >> 8;
lubomir@221: 
lubomir@281:         return Variable.getStackVariable(type, index);
lubomir@221:     }
lubomir@221: }