1 /* 2 * Copyright (c) 2011, 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.loop.phases; 26 27 import org.graalvm.compiler.loop.LoopEx; 28 import org.graalvm.compiler.loop.LoopsData; 29 import org.graalvm.compiler.nodes.FixedNode; 30 import org.graalvm.compiler.nodes.Invoke; 31 import org.graalvm.compiler.nodes.LoopEndNode; 32 import org.graalvm.compiler.nodes.StructuredGraph; 33 import org.graalvm.compiler.nodes.cfg.Block; 34 import org.graalvm.compiler.nodes.extended.ForeignCallNode; 35 import org.graalvm.compiler.phases.BasePhase; 36 import org.graalvm.compiler.phases.tiers.MidTierContext; 37 38 public class LoopSafepointEliminationPhase extends BasePhase<MidTierContext> { 39 40 @Override 41 protected void run(StructuredGraph graph, MidTierContext context) { 42 LoopsData loops = new LoopsData(graph); 43 if (context.getOptimisticOptimizations().useLoopLimitChecks(graph.getOptions()) && graph.getGuardsStage().allowsFloatingGuards()) { 44 loops.detectedCountedLoops(); 45 for (LoopEx loop : loops.countedLoops()) { 46 if (loop.loop().getChildren().isEmpty() && loop.counted().getStamp().getBits() <= 32) { 47 boolean hasSafepoint = false; 48 for (LoopEndNode loopEnd : loop.loopBegin().loopEnds()) { 49 hasSafepoint |= loopEnd.canSafepoint(); 50 } 51 if (hasSafepoint) { 52 loop.counted().createOverFlowGuard(); 53 loop.loopBegin().disableSafepoint(); 54 } 55 } 56 } 57 } 58 for (LoopEx loop : loops.loops()) { 59 for (LoopEndNode loopEnd : loop.loopBegin().loopEnds()) { 60 Block b = loops.getCFG().blockFor(loopEnd); 61 blocks: while (b != loop.loop().getHeader()) { 62 assert b != null; 63 for (FixedNode node : b.getNodes()) { 64 if (node instanceof Invoke || (node instanceof ForeignCallNode && ((ForeignCallNode) node).isGuaranteedSafepoint())) { 65 loopEnd.disableSafepoint(); 66 break blocks; 67 } 68 } 69 b = b.getDominator(); 70 } 71 } 72 } 73 loops.deleteUnusedNodes(); 74 } 75 }