| /* |
| * Copyright (c) 2009, 2016, 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 org.graalvm.compiler.nodes; |
| |
| import static org.graalvm.compiler.nodeinfo.InputType.Association; |
| import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_0; |
| import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_1; |
| |
| import java.util.Iterator; |
| |
| import org.graalvm.compiler.core.common.type.Stamp; |
| import org.graalvm.compiler.graph.Node; |
| import org.graalvm.compiler.graph.NodeClass; |
| import org.graalvm.compiler.graph.NodeInputList; |
| import org.graalvm.compiler.graph.iterators.NodeIterable; |
| import org.graalvm.compiler.graph.spi.Canonicalizable; |
| import org.graalvm.compiler.graph.spi.CanonicalizerTool; |
| import org.graalvm.compiler.nodeinfo.NodeInfo; |
| import org.graalvm.compiler.nodeinfo.Verbosity; |
| import org.graalvm.compiler.nodes.calc.FloatingNode; |
| |
| /** |
| * {@code PhiNode}s represent the merging of edges at a control flow merges ( |
| * {@link AbstractMergeNode} or {@link LoopBeginNode}). For a {@link AbstractMergeNode}, the order |
| * of the values corresponds to the order of the ends. For {@link LoopBeginNode}s, the first value |
| * corresponds to the loop's predecessor, while the rest of the values correspond to the |
| * {@link LoopEndNode}s. |
| */ |
| @NodeInfo(cycles = CYCLES_0, size = SIZE_1) |
| public abstract class PhiNode extends FloatingNode implements Canonicalizable { |
| |
| public static final NodeClass<PhiNode> TYPE = NodeClass.create(PhiNode.class); |
| @Input(Association) protected AbstractMergeNode merge; |
| |
| protected PhiNode(NodeClass<? extends PhiNode> c, Stamp stamp, AbstractMergeNode merge) { |
| super(c, stamp); |
| this.merge = merge; |
| } |
| |
| public abstract NodeInputList<ValueNode> values(); |
| |
| public AbstractMergeNode merge() { |
| return merge; |
| } |
| |
| public void setMerge(AbstractMergeNode x) { |
| updateUsages(merge, x); |
| merge = x; |
| } |
| |
| @Override |
| public boolean verify() { |
| assertTrue(merge() != null, "missing merge"); |
| assertTrue(merge().phiPredecessorCount() == valueCount(), "mismatch between merge predecessor count and phi value count: %d != %d", merge().phiPredecessorCount(), valueCount()); |
| return super.verify(); |
| } |
| |
| /** |
| * Get the instruction that produces the value associated with the i'th predecessor of the |
| * merge. |
| * |
| * @param i the index of the predecessor |
| * @return the instruction that produced the value in the i'th predecessor |
| */ |
| public ValueNode valueAt(int i) { |
| return values().get(i); |
| } |
| |
| /** |
| * Sets the value at the given index and makes sure that the values list is large enough. |
| * |
| * @param i the index at which to set the value |
| * @param x the new phi input value for the given location |
| */ |
| public void initializeValueAt(int i, ValueNode x) { |
| while (values().size() <= i) { |
| values().add(null); |
| } |
| values().set(i, x); |
| } |
| |
| public void setValueAt(int i, ValueNode x) { |
| values().set(i, x); |
| } |
| |
| public void setValueAt(AbstractEndNode end, ValueNode x) { |
| setValueAt(merge().phiPredecessorIndex(end), x); |
| } |
| |
| public ValueNode valueAt(AbstractEndNode pred) { |
| return valueAt(merge().phiPredecessorIndex(pred)); |
| } |
| |
| /** |
| * Get the number of inputs to this phi (i.e. the number of predecessors to the merge). |
| * |
| * @return the number of inputs in this phi |
| */ |
| public int valueCount() { |
| return values().size(); |
| } |
| |
| public void clearValues() { |
| values().clear(); |
| } |
| |
| @Override |
| public String toString(Verbosity verbosity) { |
| if (verbosity == Verbosity.Name) { |
| StringBuilder str = new StringBuilder(); |
| for (int i = 0; i < valueCount(); ++i) { |
| if (i != 0) { |
| str.append(' '); |
| } |
| str.append(valueAt(i) == null ? "-" : valueAt(i).toString(Verbosity.Id)); |
| } |
| return super.toString(Verbosity.Name) + "(" + str + ")"; |
| } else { |
| return super.toString(verbosity); |
| } |
| } |
| |
| public void addInput(ValueNode x) { |
| assert !(x instanceof ValuePhiNode) || ((ValuePhiNode) x).merge() instanceof LoopBeginNode || ((ValuePhiNode) x).merge() != this.merge(); |
| assert !(this instanceof ValuePhiNode) || x.stamp().isCompatible(stamp()); |
| values().add(x); |
| } |
| |
| public void removeInput(int index) { |
| values().remove(index); |
| } |
| |
| public NodeIterable<ValueNode> backValues() { |
| return values().subList(merge().forwardEndCount()); |
| } |
| |
| @NodeInfo |
| static final class MultipleValuesNode extends ValueNode { |
| |
| public static final NodeClass<MultipleValuesNode> TYPE = NodeClass.create(MultipleValuesNode.class); |
| |
| protected MultipleValuesNode() { |
| super(TYPE, null); |
| } |
| |
| } |
| |
| public static final ValueNode MULTIPLE_VALUES = new MultipleValuesNode(); |
| |
| /** |
| * If all inputs are the same value, this value is returned, otherwise {@link #MULTIPLE_VALUES}. |
| * Note that {@code null} is a valid return value, since {@link GuardPhiNode}s can have |
| * {@code null} inputs. |
| */ |
| public ValueNode singleValue() { |
| ValueNode singleValue = valueAt(0); |
| int count = valueCount(); |
| for (int i = 1; i < count; ++i) { |
| ValueNode value = valueAt(i); |
| if (value != this) { |
| if (value != singleValue) { |
| return MULTIPLE_VALUES; |
| } |
| } |
| } |
| return singleValue; |
| } |
| |
| /** |
| * If all inputs (but the first one) are the same value, this value is returned, otherwise |
| * {@link #MULTIPLE_VALUES}. Note that {@code null} is a valid return value, since |
| * {@link GuardPhiNode}s can have {@code null} inputs. |
| */ |
| public ValueNode singleBackValue() { |
| assert merge() instanceof LoopBeginNode; |
| Iterator<ValueNode> iterator = values().iterator(); |
| iterator.next(); |
| ValueNode singleValue = iterator.next(); |
| while (iterator.hasNext()) { |
| if (iterator.next() != singleValue) { |
| return MULTIPLE_VALUES; |
| } |
| } |
| return singleValue; |
| } |
| |
| @Override |
| public ValueNode canonical(CanonicalizerTool tool) { |
| |
| if (isLoopPhi()) { |
| if (singleBackValue() == this) { |
| return firstValue(); |
| } |
| |
| boolean onlySelfUsage = true; |
| for (Node n : this.usages()) { |
| if (n != this) { |
| onlySelfUsage = false; |
| break; |
| } |
| } |
| |
| if (onlySelfUsage) { |
| return null; |
| } |
| } |
| |
| ValueNode singleValue = singleValue(); |
| if (singleValue != MULTIPLE_VALUES) { |
| return singleValue; |
| } |
| return this; |
| } |
| |
| public ValueNode firstValue() { |
| return valueAt(0); |
| } |
| |
| public boolean isLoopPhi() { |
| return merge() instanceof LoopBeginNode; |
| } |
| |
| public boolean hasValidInput() { |
| for (ValueNode n : values()) { |
| if (n != null) { |
| return true; |
| } |
| } |
| return false; |
| } |
| } |