1 /*
   2  * Copyright (c) 2011, 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.core.test;
  24 
  25 import org.junit.Test;
  26 
  27 import org.graalvm.compiler.debug.Debug;
  28 import org.graalvm.compiler.debug.Debug.Scope;
  29 import org.graalvm.compiler.debug.DebugDumpScope;
  30 import org.graalvm.compiler.nodes.StructuredGraph;
  31 import org.graalvm.compiler.nodes.StructuredGraph.AllowAssumptions;
  32 import org.graalvm.compiler.phases.common.CanonicalizerPhase;
  33 import org.graalvm.compiler.phases.common.inlining.InliningPhase;
  34 import org.graalvm.compiler.phases.tiers.HighTierContext;
  35 
  36 /**
  37  * In the following tests, the usages of local variable "a" are replaced with the integer constant
  38  * 0. Then canonicalization is applied and it is verified that the resulting graph is equal to the
  39  * graph of the method that just has a "return 1" statement in it.
  40  */
  41 public class DegeneratedLoopsTest extends GraalCompilerTest {
  42 
  43     private static final String REFERENCE_SNIPPET = "referenceSnippet";
  44 
  45     @SuppressWarnings("all")
  46     public static int referenceSnippet(int a) {
  47         return a;
  48     }
  49 
  50     @Test
  51     public void test1() {
  52         test("test1Snippet");
  53     }
  54 
  55     private static class UnresolvedException extends RuntimeException {
  56 
  57         private static final long serialVersionUID = 5215434338750728440L;
  58 
  59         static {
  60             if (true) {
  61                 throw new UnsupportedOperationException("this class may never be initialized");
  62             }
  63         }
  64     }
  65 
  66     @SuppressWarnings("all")
  67     public static int test1Snippet(int a) {
  68         for (;;) {
  69             try {
  70                 test();
  71                 break;
  72             } catch (UnresolvedException e) {
  73             }
  74         }
  75         return a;
  76     }
  77 
  78     private static void test() {
  79 
  80     }
  81 
  82     @SuppressWarnings("try")
  83     private void test(final String snippet) {
  84         try (Scope s = Debug.scope("DegeneratedLoopsTest", new DebugDumpScope(snippet))) {
  85             StructuredGraph graph = parseEager(snippet, AllowAssumptions.YES);
  86             HighTierContext context = getDefaultHighTierContext();
  87             new InliningPhase(new CanonicalizerPhase()).apply(graph, context);
  88             new CanonicalizerPhase().apply(graph, context);
  89             Debug.dump(Debug.BASIC_LOG_LEVEL, graph, "Graph");
  90             StructuredGraph referenceGraph = parseEager(REFERENCE_SNIPPET, AllowAssumptions.YES);
  91             Debug.dump(Debug.BASIC_LOG_LEVEL, referenceGraph, "ReferenceGraph");
  92             assertEquals(referenceGraph, graph);
  93         } catch (Throwable e) {
  94             throw Debug.handle(e);
  95         }
  96     }
  97 }