| /******************************************************************************* |
| * Copyright (c) 2009, 2018 Mountainminds GmbH & Co. KG and Contributors |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/epl-v10.html |
| * |
| * Contributors: |
| * Marc R. Hoffmann - initial API and implementation |
| * |
| *******************************************************************************/ |
| |
| package org.jacoco.core.internal.flow; |
| |
| import java.util.ArrayList; |
| import java.util.List; |
| |
| import org.objectweb.asm.MethodVisitor; |
| import org.objectweb.asm.Opcodes; |
| import org.objectweb.asm.commons.AnalyzerAdapter; |
| |
| /** |
| * IFrame implementation which creates snapshots from an {@link AnalyzerAdapter} |
| */ |
| class FrameSnapshot implements IFrame { |
| |
| private static final FrameSnapshot NOP = new FrameSnapshot(null, null); |
| |
| private final Object[] locals; |
| private final Object[] stack; |
| |
| private FrameSnapshot(final Object[] locals, final Object[] stack) { |
| this.locals = locals; |
| this.stack = stack; |
| } |
| |
| /** |
| * Create a IFrame instance based on the given analyzer. |
| * |
| * @param analyzer |
| * analyzer instance or <code>null</code> |
| * @param popCount |
| * number of items to remove from the operand stack |
| * @return IFrame instance. In case the analyzer is <code>null</code> or |
| * does not contain stackmap information a "NOP" IFrame is returned. |
| */ |
| static IFrame create(final AnalyzerAdapter analyzer, final int popCount) { |
| if (analyzer == null || analyzer.locals == null) { |
| return NOP; |
| } |
| final Object[] locals = reduce(analyzer.locals, 0); |
| final Object[] stack = reduce(analyzer.stack, popCount); |
| return new FrameSnapshot(locals, stack); |
| } |
| |
| /** |
| * Reduce double word types into a single slot as required |
| * {@link MethodVisitor#visitFrame(int, int, Object[], int, Object[])} |
| * method. |
| */ |
| private static Object[] reduce(final List<Object> source, final int popCount) { |
| final List<Object> copy = new ArrayList<Object>(source); |
| final int size = source.size() - popCount; |
| copy.subList(size, source.size()).clear(); |
| for (int i = size; --i >= 0;) { |
| final Object type = source.get(i); |
| if (type == Opcodes.LONG || type == Opcodes.DOUBLE) { |
| copy.remove(i + 1); |
| } |
| } |
| return copy.toArray(); |
| } |
| |
| // === IFrame implementation === |
| |
| public void accept(final MethodVisitor mv) { |
| if (locals != null) { |
| mv.visitFrame(Opcodes.F_NEW, locals.length, locals, stack.length, |
| stack); |
| } |
| } |
| |
| } |