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 21 * questions. 22 */ 23 package org.graalvm.compiler.api.directives.test; 24 25 import org.junit.Assert; 26 import org.junit.Test; 27 28 import org.graalvm.compiler.api.directives.GraalDirectives; 29 import org.graalvm.compiler.core.test.GraalCompilerTest; 30 import org.graalvm.compiler.graph.iterators.NodeIterable; 31 import org.graalvm.compiler.nodes.LoopBeginNode; 32 import org.graalvm.compiler.nodes.StructuredGraph; 33 34 public 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 }