001/*
002 * Copyright (c) 2014, 2014, Oracle and/or its affiliates. All rights reserved.
003 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
004 *
005 * This code is free software; you can redistribute it and/or modify it
006 * under the terms of the GNU General Public License version 2 only, as
007 * published by the Free Software Foundation.
008 *
009 * This code is distributed in the hope that it will be useful, but WITHOUT
010 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
011 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
012 * version 2 for more details (a copy is included in the LICENSE file that
013 * accompanied this code).
014 *
015 * You should have received a copy of the GNU General Public License version
016 * 2 along with this work; if not, write to the Free Software Foundation,
017 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
018 *
019 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
020 * or visit www.oracle.com if you need additional information or have any
021 * questions.
022 */
023package com.oracle.graal.nodes.cfg;
024
025import jdk.internal.jvmci.meta.*;
026
027import com.oracle.graal.compiler.common.cfg.*;
028import com.oracle.graal.nodes.*;
029
030public final class HIRLoop extends Loop<Block> {
031
032    private LocationSet killLocations;
033
034    protected HIRLoop(Loop<Block> parent, int index, Block header) {
035        super(parent, index, header);
036    }
037
038    @Override
039    public long numBackedges() {
040        return ((LoopBeginNode) getHeader().getBeginNode()).loopEnds().count();
041    }
042
043    public LocationSet getKillLocations() {
044        if (killLocations == null) {
045            killLocations = new LocationSet();
046            for (Block b : this.getBlocks()) {
047                if (b.getLoop() == this) {
048                    killLocations.addAll(b.getKillLocations());
049                    if (killLocations.isAny()) {
050                        break;
051                    }
052                }
053            }
054        }
055        for (Loop<Block> child : this.getChildren()) {
056            if (killLocations.isAny()) {
057                break;
058            }
059            killLocations.addAll(((HIRLoop) child).getKillLocations());
060        }
061        return killLocations;
062    }
063
064    public boolean canKill(LocationIdentity location) {
065        return getKillLocations().contains(location);
066    }
067}