org.objectweb.asm.tree.analysis.Subroutine Maven / Gradle / Ivy
/***
* ASM: a very small and fast Java bytecode manipulation framework
* Copyright (c) 2000-2011 INRIA, France Telecom
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGE.
*/
package org.objectweb.asm.tree.analysis;
import java.util.ArrayList;
import java.util.List;
import org.objectweb.asm.tree.JumpInsnNode;
import org.objectweb.asm.tree.LabelNode;
/**
* A method subroutine (corresponds to a JSR instruction).
*
* @author Eric Bruneton
*/
class Subroutine {
LabelNode start;
boolean[] access;
List callers;
private Subroutine() {
}
Subroutine(final LabelNode start, final int maxLocals,
final JumpInsnNode caller) {
this.start = start;
this.access = new boolean[maxLocals];
this.callers = new ArrayList();
callers.add(caller);
}
public Subroutine copy() {
Subroutine result = new Subroutine();
result.start = start;
result.access = new boolean[access.length];
System.arraycopy(access, 0, result.access, 0, access.length);
result.callers = new ArrayList(callers);
return result;
}
public boolean merge(final Subroutine subroutine) throws AnalyzerException {
boolean changes = false;
for (int i = 0; i < access.length; ++i) {
if (subroutine.access[i] && !access[i]) {
access[i] = true;
changes = true;
}
}
if (subroutine.start == start) {
for (int i = 0; i < subroutine.callers.size(); ++i) {
JumpInsnNode caller = subroutine.callers.get(i);
if (!callers.contains(caller)) {
callers.add(caller);
changes = true;
}
}
}
return changes;
}
}