IterationDirectiveTest.java revision 12651:6ef01bd40ce2 
1/*
2 * Copyright (c) 2015, 2015, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
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22 */
23package org.graalvm.compiler.api.directives.test;
24
25import org.junit.Assert;
26import org.junit.Test;
27
28import org.graalvm.compiler.api.directives.GraalDirectives;
29import org.graalvm.compiler.core.test.GraalCompilerTest;
30import org.graalvm.compiler.graph.iterators.NodeIterable;
31import org.graalvm.compiler.nodes.LoopBeginNode;
32import org.graalvm.compiler.nodes.StructuredGraph;
33
34public class IterationDirectiveTest extends GraalCompilerTest {
35
36    public static int loopFrequencySnippet(int arg) {
37        int x = arg;
38        while (GraalDirectives.injectIterationCount(128, x > 1)) {
39            GraalDirectives.controlFlowAnchor(); // prevent loop peeling or unrolling
40            if (x % 2 == 0) {
41                x /= 2;
42            } else {
43                x = 3 * x + 1;
44            }
45        }
46        return x;
47    }
48
49    @Test
50    public void testLoopFrequency() {
51        test("loopFrequencySnippet", 7);
52    }
53
54    @Override
55    protected boolean checkLowTierGraph(StructuredGraph graph) {
56        NodeIterable<LoopBeginNode> loopBeginNodes = graph.getNodes(LoopBeginNode.TYPE);
57        Assert.assertEquals("LoopBeginNode count", 1, loopBeginNodes.count());
58
59        LoopBeginNode loopBeginNode = loopBeginNodes.first();
60        Assert.assertEquals("loop frequency of " + loopBeginNode, 128, loopBeginNode.loopFrequency(), 0);
61
62        return true;
63    }
64}
65