/*
* Copyright (C) 2011 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.dexmaker;
import com.android.dx.rop.code.BasicBlock;
import com.android.dx.rop.code.Insn;
import com.android.dx.rop.code.InsnList;
import com.android.dx.util.IntList;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
/**
* A branch target in a list of instructions.
*/
public final class Label {
final List<Insn> instructions = new ArrayList<Insn>();
Code code;
boolean marked = false;
/** an immutable list of labels corresponding to the types in the catch list */
List<Label> catchLabels = Collections.emptyList();
/** contains the next instruction if no branch occurs */
Label primarySuccessor;
/** contains the instruction to jump to if the if is true */
Label alternateSuccessor;
int id = -1;
public Label() {}
boolean isEmpty() {
return instructions.isEmpty();
}
void compact() {
for (int i = 0; i < catchLabels.size(); i++) {
while (catchLabels.get(i).isEmpty()) {
catchLabels.set(i, catchLabels.get(i).primarySuccessor);
}
}
while (primarySuccessor != null && primarySuccessor.isEmpty()) {
primarySuccessor = primarySuccessor.primarySuccessor;
}
while (alternateSuccessor != null && alternateSuccessor.isEmpty()) {
alternateSuccessor = alternateSuccessor.primarySuccessor;
}
}
BasicBlock toBasicBlock() {
InsnList result = new InsnList(instructions.size());
for (int i = 0; i < instructions.size(); i++) {
result.set(i, instructions.get(i));
}
result.setImmutable();
int primarySuccessorIndex = -1;
IntList successors = new IntList();
for (Label catchLabel : catchLabels) {
successors.add(catchLabel.id);
}
if (primarySuccessor != null) {
primarySuccessorIndex = primarySuccessor.id;
successors.add(primarySuccessorIndex);
}
if (alternateSuccessor != null) {
successors.add(alternateSuccessor.id);
}
successors.setImmutable();
return new BasicBlock(id, result, successors, primarySuccessorIndex);
}
}