proguard.evaluation.BasicBranchUnit Maven / Gradle / Ivy
/*
* ProGuard -- shrinking, optimization, obfuscation, and preverification
* of Java bytecode.
*
* Copyright (c) 2002-2019 Guardsquare NV
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
package proguard.evaluation;
import proguard.classfile.Clazz;
import proguard.classfile.attribute.CodeAttribute;
import proguard.evaluation.value.InstructionOffsetValue;
/**
* This BranchUnit remembers the branch unit commands that are invoked on it.
* It doesn't consider conditions when branching.
*
* @author Eric Lafortune
*/
public class BasicBranchUnit
implements BranchUnit
{
protected InstructionOffsetValue traceBranchTargets;
protected boolean wasCalled;
/**
* Resets the accumulated branch targets and the flag that tells whether
* any of the branch unit methods was called.
*/
public void reset()
{
traceBranchTargets = InstructionOffsetValue.EMPTY_VALUE;
wasCalled = false;
}
/**
* Returns whether any of the branch unit methods was called.
*/
public boolean wasCalled()
{
return wasCalled;
}
/**
* Returns the accumulated branch targets that were passed to the branch
* unit methods.
*/
public InstructionOffsetValue getTraceBranchTargets()
{
return traceBranchTargets;
}
// Implementations for BranchUnit.
public void branch(Clazz clazz,
CodeAttribute codeAttribute,
int offset,
int branchTarget)
{
// Override the branch targets.
traceBranchTargets = new InstructionOffsetValue(branchTarget);
wasCalled = true;
}
public void branchConditionally(Clazz clazz,
CodeAttribute codeAttribute,
int offset,
int branchTarget,
int conditional)
{
// Accumulate the branch targets.
traceBranchTargets =
traceBranchTargets.add(branchTarget);
wasCalled = true;
}
public void returnFromMethod()
{
// Stop processing this block.
traceBranchTargets = InstructionOffsetValue.EMPTY_VALUE;
wasCalled = true;
}
public void throwException()
{
// Stop processing this block.
traceBranchTargets = InstructionOffsetValue.EMPTY_VALUE;
wasCalled = true;
}
}