1 /*
   2  * Copyright (c) 2011, 2013, 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.phases.common;
  24 
  25 import static org.graalvm.compiler.core.common.GraalOptions.GenLoopSafepoints;
  26 
  27 import org.graalvm.compiler.nodes.LoopEndNode;
  28 import org.graalvm.compiler.nodes.SafepointNode;
  29 import org.graalvm.compiler.nodes.StructuredGraph;
  30 import org.graalvm.compiler.phases.Phase;
  31 
  32 /**
  33  * Adds safepoints to loops.
  34  */
  35 public class LoopSafepointInsertionPhase extends Phase {
  36 
  37     @Override
  38     public boolean checkContract() {
  39         // the size / cost after is highly dynamic and dependent on the graph, thus we do not verify
  40         // costs for this phase
  41         return false;
  42     }
  43 
  44     @Override
  45     protected void run(StructuredGraph graph) {
  46         if (GenLoopSafepoints.getValue()) {
  47             for (LoopEndNode loopEndNode : graph.getNodes(LoopEndNode.TYPE)) {
  48                 if (loopEndNode.canSafepoint()) {
  49                     SafepointNode safepointNode = graph.add(new SafepointNode());
  50                     graph.addBeforeFixed(loopEndNode, safepointNode);
  51                 }
  52             }
  53         }
  54     }
  55 }