1 /*
   2  * Copyright (c) 2012, 2018, 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.core.test;
  26 
  27 import org.graalvm.compiler.debug.DebugContext;
  28 import org.graalvm.compiler.nodes.AbstractBeginNode;
  29 import org.graalvm.compiler.nodes.AbstractMergeNode;
  30 import org.graalvm.compiler.nodes.BeginNode;
  31 import org.graalvm.compiler.nodes.EndNode;
  32 import org.graalvm.compiler.nodes.IfNode;
  33 import org.graalvm.compiler.nodes.MergeNode;
  34 import org.graalvm.compiler.nodes.ReturnNode;
  35 import org.graalvm.compiler.nodes.StructuredGraph;
  36 import org.graalvm.compiler.nodes.StructuredGraph.AllowAssumptions;
  37 import org.graalvm.compiler.nodes.cfg.Block;
  38 import org.graalvm.compiler.nodes.cfg.ControlFlowGraph;
  39 import org.graalvm.compiler.options.OptionValues;
  40 import org.graalvm.compiler.printer.GraalDebugHandlersFactory;
  41 import org.junit.Assert;
  42 import org.junit.Test;
  43 
  44 public class SimpleCFGTest extends GraalCompilerTest {
  45 
  46     private static void dumpGraph(final StructuredGraph graph) {
  47         DebugContext debug = graph.getDebug();
  48         debug.dump(DebugContext.BASIC_LEVEL, graph, "Graph");
  49     }
  50 
  51     @Test
  52     public void testImplies() {
  53         OptionValues options = getInitialOptions();
  54         DebugContext debug = DebugContext.create(options, new GraalDebugHandlersFactory(getSnippetReflection()));
  55         StructuredGraph graph = new StructuredGraph.Builder(options, debug, AllowAssumptions.YES).build();
  56 
  57         EndNode trueEnd = graph.add(new EndNode());
  58         EndNode falseEnd = graph.add(new EndNode());
  59 
  60         AbstractBeginNode trueBegin = graph.add(new BeginNode());
  61         trueBegin.setNext(trueEnd);
  62         AbstractBeginNode falseBegin = graph.add(new BeginNode());
  63         falseBegin.setNext(falseEnd);
  64 
  65         IfNode ifNode = graph.add(new IfNode(null, trueBegin, falseBegin, 0.5));
  66         graph.start().setNext(ifNode);
  67 
  68         AbstractMergeNode merge = graph.add(new MergeNode());
  69         merge.addForwardEnd(trueEnd);
  70         merge.addForwardEnd(falseEnd);
  71         ReturnNode returnNode = graph.add(new ReturnNode(null));
  72         merge.setNext(returnNode);
  73 
  74         dumpGraph(graph);
  75 
  76         ControlFlowGraph cfg = ControlFlowGraph.compute(graph, true, true, true, true);
  77 
  78         Block[] blocks = cfg.getBlocks();
  79         // check number of blocks
  80         assertDeepEquals(4, blocks.length);
  81 
  82         // check block - node assignment
  83         assertDeepEquals(blocks[0], cfg.blockFor(graph.start()));
  84         assertDeepEquals(blocks[0], cfg.blockFor(ifNode));
  85         assertDeepEquals(blocks[1], cfg.blockFor(trueBegin));
  86         assertDeepEquals(blocks[1], cfg.blockFor(trueEnd));
  87         assertDeepEquals(blocks[2], cfg.blockFor(falseBegin));
  88         assertDeepEquals(blocks[2], cfg.blockFor(falseEnd));
  89         assertDeepEquals(blocks[3], cfg.blockFor(merge));
  90         assertDeepEquals(blocks[3], cfg.blockFor(returnNode));
  91 
  92         // check dominators
  93         assertDominator(blocks[0], null);
  94         assertDominator(blocks[1], blocks[0]);
  95         assertDominator(blocks[2], blocks[0]);
  96         assertDominator(blocks[3], blocks[0]);
  97 
  98         // check dominated
  99         assertDominatedSize(blocks[0], 3);
 100         assertDominatedSize(blocks[1], 0);
 101         assertDominatedSize(blocks[2], 0);
 102         assertDominatedSize(blocks[3], 0);
 103 
 104         // check postdominators
 105         assertPostdominator(blocks[0], blocks[3]);
 106         assertPostdominator(blocks[1], blocks[3]);
 107         assertPostdominator(blocks[2], blocks[3]);
 108         assertPostdominator(blocks[3], null);
 109     }
 110 
 111     public static void assertDominator(Block block, Block expectedDominator) {
 112         Assert.assertEquals("dominator of " + block, expectedDominator, block.getDominator());
 113     }
 114 
 115     public static void assertDominatedSize(Block block, int size) {
 116         int count = 0;
 117         Block domChild = block.getFirstDominated();
 118         while (domChild != null) {
 119             count++;
 120             domChild = domChild.getDominatedSibling();
 121         }
 122         Assert.assertEquals("number of dominated blocks of " + block, size, count);
 123     }
 124 
 125     public static void assertPostdominator(Block block, Block expectedPostdominator) {
 126         Assert.assertEquals("postdominator of " + block, expectedPostdominator, block.getPostdominator());
 127     }
 128 
 129 }