001/*
002 * Copyright (c) 2015, 2015, Oracle and/or its affiliates. All rights reserved.
003 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
004 *
005 * This code is free software; you can redistribute it and/or modify it
006 * under the terms of the GNU General Public License version 2 only, as
007 * published by the Free Software Foundation.
008 *
009 * This code is distributed in the hope that it will be useful, but WITHOUT
010 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
011 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
012 * version 2 for more details (a copy is included in the LICENSE file that
013 * accompanied this code).
014 *
015 * You should have received a copy of the GNU General Public License version
016 * 2 along with this work; if not, write to the Free Software Foundation,
017 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
018 *
019 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
020 * or visit www.oracle.com if you need additional information or have any
021 * questions.
022 */
023package com.oracle.graal.api.directives.test;
024
025import org.junit.*;
026
027import com.oracle.graal.api.directives.*;
028import com.oracle.graal.compiler.test.*;
029import com.oracle.graal.graph.iterators.*;
030import com.oracle.graal.nodes.*;
031
032public class IterationDirectiveTest extends GraalCompilerTest {
033
034    public static int loopFrequencySnippet(int arg) {
035        int x = arg;
036        while (GraalDirectives.injectIterationCount(128, x > 1)) {
037            GraalDirectives.controlFlowAnchor(); // prevent loop peeling or unrolling
038            if (x % 2 == 0) {
039                x /= 2;
040            } else {
041                x = 3 * x + 1;
042            }
043        }
044        return x;
045    }
046
047    @Test
048    public void testLoopFrequency() {
049        test("loopFrequencySnippet", 7);
050    }
051
052    @Override
053    protected boolean checkLowTierGraph(StructuredGraph graph) {
054        NodeIterable<LoopBeginNode> loopBeginNodes = graph.getNodes(LoopBeginNode.TYPE);
055        Assert.assertEquals("LoopBeginNode count", 1, loopBeginNodes.count());
056
057        LoopBeginNode loopBeginNode = loopBeginNodes.first();
058        Assert.assertEquals("loop frequency of " + loopBeginNode, 128, loopBeginNode.loopFrequency(), 0);
059
060        return true;
061    }
062}