Mercurial > hg > graal-compiler
view graal/com.oracle.graal.phases.common/src/com/oracle/graal/phases/common/ValueAnchorCleanupPhase.java @ 23060:4e72c50bb9c1
Improve handling of pi nodes that directly follow access nodes.
author | Thomas Wuerthinger <thomas.wuerthinger@oracle.com> |
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date | Sun, 22 Nov 2015 19:53:38 +0100 |
parents | 05183a084a08 |
children | 2160e7da7fb0 |
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/* * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package com.oracle.graal.phases.common; import java.util.List; import java.util.Set; import com.oracle.graal.graph.Node; import com.oracle.graal.nodes.AbstractMergeNode; import com.oracle.graal.nodes.FixedNode; import com.oracle.graal.nodes.StartNode; import com.oracle.graal.nodes.StructuredGraph; import com.oracle.graal.nodes.ValueNode; import com.oracle.graal.nodes.extended.ValueAnchorNode; import com.oracle.graal.phases.Phase; import com.oracle.graal.phases.graph.MergeableState; import com.oracle.graal.phases.graph.SinglePassNodeIterator; /** * This phase performs a bit of hygiene on {@link ValueAnchorNode} by removing inputs that have * already been anchored in a dominating value anchor. Value anchors that lose their last input, * have no usages and are not marked as permanent are removed. */ public class ValueAnchorCleanupPhase extends Phase { private static class State extends MergeableState<State> implements Cloneable { private final Set<Node> anchoredValues; public State() { anchoredValues = Node.newSet(); } public State(State other) { anchoredValues = Node.newSet(other.anchoredValues); } @Override public boolean merge(AbstractMergeNode merge, List<State> withStates) { for (State other : withStates) { anchoredValues.retainAll(other.anchoredValues); } return true; } @Override public State clone() { return new State(this); } } private static class CleanupValueAnchorsClosure extends SinglePassNodeIterator<State> { public CleanupValueAnchorsClosure(StartNode start) { super(start, new State()); } @Override protected void node(FixedNode node) { if (node instanceof ValueAnchorNode) { ValueAnchorNode anchor = (ValueAnchorNode) node; ValueNode anchored = anchor.getAnchoredNode(); if (anchored != null) { if (state.anchoredValues.contains(anchored)) { anchor.removeAnchoredNode(); } else { state.anchoredValues.add(anchored); } } if (anchor.getAnchoredNode() == null && anchor.hasNoUsages()) { node.graph().removeFixed(anchor); } } } } @Override protected void run(StructuredGraph graph) { CleanupValueAnchorsClosure closure = new CleanupValueAnchorsClosure(graph.start()); closure.apply(); } }