| /* |
| * Copyright (c) 2009, 2011, 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_0; |
| |
| import java.util.List; |
| |
| import org.graalvm.compiler.debug.Debug; |
| import org.graalvm.compiler.graph.IterableNodeType; |
| 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.Simplifiable; |
| import org.graalvm.compiler.graph.spi.SimplifierTool; |
| import org.graalvm.compiler.nodeinfo.NodeInfo; |
| import org.graalvm.compiler.nodes.spi.LIRLowerable; |
| import org.graalvm.compiler.nodes.spi.NodeLIRBuilderTool; |
| import org.graalvm.compiler.nodes.util.GraphUtil; |
| |
| /** |
| * Denotes the merging of multiple control-flow paths. |
| */ |
| @NodeInfo(allowedUsageTypes = Association, cycles = CYCLES_0, size = SIZE_0) |
| public abstract class AbstractMergeNode extends BeginStateSplitNode implements IterableNodeType, Simplifiable, LIRLowerable { |
| public static final NodeClass<AbstractMergeNode> TYPE = NodeClass.create(AbstractMergeNode.class); |
| |
| protected AbstractMergeNode(NodeClass<? extends AbstractMergeNode> c) { |
| super(c); |
| } |
| |
| @Input(Association) protected NodeInputList<EndNode> ends = new NodeInputList<>(this); |
| |
| @Override |
| public void generate(NodeLIRBuilderTool gen) { |
| gen.visitMerge(this); |
| } |
| |
| public int forwardEndIndex(EndNode end) { |
| return ends.indexOf(end); |
| } |
| |
| public void addForwardEnd(EndNode end) { |
| ends.add(end); |
| } |
| |
| public final int forwardEndCount() { |
| return ends.size(); |
| } |
| |
| public final EndNode forwardEndAt(int index) { |
| return ends.get(index); |
| } |
| |
| @Override |
| public NodeIterable<EndNode> cfgPredecessors() { |
| return ends; |
| } |
| |
| /** |
| * Determines if a given node is a phi whose {@linkplain PhiNode#merge() merge} is this node. |
| * |
| * @param value the instruction to test |
| * @return {@code true} if {@code value} is a phi and its merge is {@code this} |
| */ |
| public boolean isPhiAtMerge(Node value) { |
| return value instanceof PhiNode && ((PhiNode) value).merge() == this; |
| } |
| |
| /** |
| * Removes the given end from the merge, along with the entries corresponding to this end in the |
| * phis connected to the merge. |
| * |
| * @param pred the end to remove |
| */ |
| public void removeEnd(AbstractEndNode pred) { |
| int predIndex = phiPredecessorIndex(pred); |
| assert predIndex != -1; |
| deleteEnd(pred); |
| for (PhiNode phi : phis().snapshot()) { |
| if (phi.isDeleted()) { |
| continue; |
| } |
| ValueNode removedValue = phi.valueAt(predIndex); |
| phi.removeInput(predIndex); |
| if (removedValue != null && removedValue.isAlive() && removedValue.hasNoUsages() && GraphUtil.isFloatingNode(removedValue)) { |
| GraphUtil.killWithUnusedFloatingInputs(removedValue); |
| } |
| } |
| } |
| |
| protected void deleteEnd(AbstractEndNode end) { |
| ends.remove(end); |
| } |
| |
| public void clearEnds() { |
| ends.clear(); |
| } |
| |
| public NodeInputList<EndNode> forwardEnds() { |
| return ends; |
| } |
| |
| public int phiPredecessorCount() { |
| return forwardEndCount(); |
| } |
| |
| public int phiPredecessorIndex(AbstractEndNode pred) { |
| return forwardEndIndex((EndNode) pred); |
| } |
| |
| public AbstractEndNode phiPredecessorAt(int index) { |
| return forwardEndAt(index); |
| } |
| |
| public NodeIterable<PhiNode> phis() { |
| return this.usages().filter(PhiNode.class).filter(this::isPhiAtMerge); |
| } |
| |
| public NodeIterable<ValuePhiNode> valuePhis() { |
| return this.usages().filter(ValuePhiNode.class).filter(this::isPhiAtMerge); |
| } |
| |
| @Override |
| public NodeIterable<Node> anchored() { |
| return super.anchored().filter(n -> !isPhiAtMerge(n)); |
| } |
| |
| /** |
| * This simplify method can deal with a null value for tool, so that it can be used outside of |
| * canonicalization. |
| */ |
| @Override |
| public void simplify(SimplifierTool tool) { |
| FixedNode currentNext = next(); |
| if (currentNext instanceof AbstractEndNode) { |
| AbstractEndNode origLoopEnd = (AbstractEndNode) currentNext; |
| AbstractMergeNode merge = origLoopEnd.merge(); |
| if (merge instanceof LoopBeginNode && !(origLoopEnd instanceof LoopEndNode)) { |
| return; |
| } |
| // in order to move anchored values to the other merge we would need to check if the |
| // anchors are used by phis of the other merge |
| if (this.anchored().isNotEmpty()) { |
| return; |
| } |
| if (merge.stateAfter() == null && this.stateAfter() != null) { |
| // We hold a state, but the succeeding merge does not => do not combine. |
| return; |
| } |
| for (PhiNode phi : phis()) { |
| for (Node usage : phi.usages()) { |
| if (!(usage instanceof VirtualState) && !merge.isPhiAtMerge(usage)) { |
| return; |
| } |
| } |
| } |
| Debug.log("Split %s into ends for %s.", this, merge); |
| int numEnds = this.forwardEndCount(); |
| for (int i = 0; i < numEnds - 1; i++) { |
| AbstractEndNode end = forwardEndAt(numEnds - 1 - i); |
| if (tool != null) { |
| tool.addToWorkList(end); |
| } |
| AbstractEndNode newEnd; |
| if (merge instanceof LoopBeginNode) { |
| newEnd = graph().add(new LoopEndNode((LoopBeginNode) merge)); |
| } else { |
| EndNode tmpEnd = graph().add(new EndNode()); |
| merge.addForwardEnd(tmpEnd); |
| newEnd = tmpEnd; |
| } |
| for (PhiNode phi : merge.phis()) { |
| ValueNode v = phi.valueAt(origLoopEnd); |
| ValueNode newInput; |
| if (isPhiAtMerge(v)) { |
| PhiNode endPhi = (PhiNode) v; |
| newInput = endPhi.valueAt(end); |
| } else { |
| newInput = v; |
| } |
| phi.addInput(newInput); |
| } |
| this.removeEnd(end); |
| end.replaceAtPredecessor(newEnd); |
| end.safeDelete(); |
| if (tool != null) { |
| tool.addToWorkList(newEnd.predecessor()); |
| } |
| } |
| graph().reduceTrivialMerge(this); |
| } else if (currentNext instanceof ReturnNode) { |
| ReturnNode returnNode = (ReturnNode) currentNext; |
| if (anchored().isNotEmpty() || returnNode.getMemoryMap() != null) { |
| return; |
| } |
| List<PhiNode> phis = phis().snapshot(); |
| for (PhiNode phi : phis) { |
| for (Node usage : phi.usages()) { |
| if (usage != returnNode && !(usage instanceof FrameState)) { |
| return; |
| } |
| } |
| } |
| |
| ValuePhiNode returnValuePhi = returnNode.result() == null || !isPhiAtMerge(returnNode.result()) ? null : (ValuePhiNode) returnNode.result(); |
| List<EndNode> endNodes = forwardEnds().snapshot(); |
| for (EndNode end : endNodes) { |
| ReturnNode newReturn = graph().add(new ReturnNode(returnValuePhi == null ? returnNode.result() : returnValuePhi.valueAt(end))); |
| if (tool != null) { |
| tool.addToWorkList(end.predecessor()); |
| } |
| end.replaceAtPredecessor(newReturn); |
| } |
| GraphUtil.killCFG(this); |
| for (EndNode end : endNodes) { |
| end.safeDelete(); |
| } |
| for (PhiNode phi : phis) { |
| if (tool.allUsagesAvailable() && phi.isAlive() && phi.hasNoUsages()) { |
| GraphUtil.killWithUnusedFloatingInputs(phi); |
| } |
| } |
| } |
| } |
| } |
