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 24 25 package org.graalvm.compiler.api.directives.test; 26 27 import org.junit.Assert; 28 import org.junit.Test; 29 30 import org.graalvm.compiler.api.directives.GraalDirectives; 31 import org.graalvm.compiler.core.test.GraalCompilerTest; 32 import org.graalvm.compiler.graph.iterators.NodeIterable; 33 import org.graalvm.compiler.nodes.LoopBeginNode; 34 import org.graalvm.compiler.nodes.StructuredGraph; 35 36 public class IterationDirectiveTest extends GraalCompilerTest { 37 38 public static int loopFrequencySnippet(int arg) { 39 int x = arg; 40 while (GraalDirectives.injectIterationCount(128, x > 1)) { 41 GraalDirectives.controlFlowAnchor(); // prevent loop peeling or unrolling 42 if (x % 2 == 0) { 43 x /= 2; 44 } else { 45 x = 3 * x + 1; 46 } 47 } 48 return x; 49 } 50 51 @Test 52 public void testLoopFrequency() { 53 test("loopFrequencySnippet", 7); 54 } 55 56 @Override 57 protected boolean checkLowTierGraph(StructuredGraph graph) { 58 NodeIterable<LoopBeginNode> loopBeginNodes = graph.getNodes(LoopBeginNode.TYPE); 59 Assert.assertEquals("LoopBeginNode count", 1, loopBeginNodes.count()); 60 61 LoopBeginNode loopBeginNode = loopBeginNodes.first(); 62 Assert.assertEquals("loop frequency of " + loopBeginNode, 128, loopBeginNode.loopFrequency(), 0); 63 64 return true; 65 } 66 }