--- /dev/null 2017-01-22 10:16:57.869617664 -0800 +++ new/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.nodes/src/org/graalvm/compiler/nodes/extended/SwitchNode.java 2017-02-15 17:07:24.564642961 -0800 @@ -0,0 +1,204 @@ +/* + * Copyright (c) 2009, 2015, 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.extended; + +import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_UNKNOWN; +import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_UNKNOWN; + +import java.util.Arrays; + +import org.graalvm.compiler.core.common.type.AbstractPointerStamp; +import org.graalvm.compiler.core.common.type.StampFactory; +import org.graalvm.compiler.debug.GraalError; +import org.graalvm.compiler.graph.Node; +import org.graalvm.compiler.graph.NodeClass; +import org.graalvm.compiler.graph.NodeSuccessorList; +import org.graalvm.compiler.graph.spi.SimplifierTool; +import org.graalvm.compiler.nodeinfo.NodeInfo; +import org.graalvm.compiler.nodes.AbstractBeginNode; +import org.graalvm.compiler.nodes.ControlSplitNode; +import org.graalvm.compiler.nodes.ValueNode; + +import jdk.vm.ci.meta.Constant; + +/** + * The {@code SwitchNode} class is the base of both lookup and table switches. + */ +// @formatter:off +@NodeInfo(cycles = CYCLES_UNKNOWN, + cyclesRationale = "We cannot estimate the runtime cost of a switch statement without knowing the number" + + "of case statements and the involved keys.", + size = SIZE_UNKNOWN, + sizeRationale = "We cannot estimate the code size of a switch statement without knowing the number" + + "of case statements.") +// @formatter:on +public abstract class SwitchNode extends ControlSplitNode { + + public static final NodeClass TYPE = NodeClass.create(SwitchNode.class); + @Successor protected NodeSuccessorList successors; + @Input protected ValueNode value; + + // do not change the contents of these arrays: + protected final double[] keyProbabilities; + protected final int[] keySuccessors; + + /** + * Constructs a new Switch. + * + * @param value the instruction that provides the value to be switched over + * @param successors the list of successors of this switch + */ + protected SwitchNode(NodeClass c, ValueNode value, AbstractBeginNode[] successors, int[] keySuccessors, double[] keyProbabilities) { + super(c, StampFactory.forVoid()); + assert value.stamp().getStackKind().isNumericInteger() || value.stamp() instanceof AbstractPointerStamp : value.stamp() + " key not supported by SwitchNode"; + assert keySuccessors.length == keyProbabilities.length; + this.successors = new NodeSuccessorList<>(this, successors); + this.value = value; + this.keySuccessors = keySuccessors; + this.keyProbabilities = keyProbabilities; + assert assertProbabilities(); + } + + private boolean assertProbabilities() { + double total = 0; + for (double d : keyProbabilities) { + total += d; + assert d >= 0.0 : "Cannot have negative probabilities in switch node: " + d; + } + assert total > 0.999 && total < 1.001 : "Total " + total; + return true; + } + + @Override + public double probability(AbstractBeginNode successor) { + double sum = 0; + for (int i = 0; i < keySuccessors.length; i++) { + if (successors.get(keySuccessors[i]) == successor) { + sum += keyProbabilities[i]; + } + } + return sum; + } + + public ValueNode value() { + return value; + } + + public abstract boolean isSorted(); + + /** + * The number of distinct keys in this switch. + */ + public abstract int keyCount(); + + /** + * The key at the specified position, encoded in a Constant. + */ + public abstract Constant keyAt(int i); + + public boolean structureEquals(SwitchNode switchNode) { + return Arrays.equals(keySuccessors, switchNode.keySuccessors) && equalKeys(switchNode); + } + + /** + * Returns true if the switch has the same keys in the same order as this switch. + */ + public abstract boolean equalKeys(SwitchNode switchNode); + + /** + * Returns the index of the successor belonging to the key at the specified index. + */ + public int keySuccessorIndex(int i) { + return keySuccessors[i]; + } + + /** + * Returns the successor for the key at the given index. + */ + public AbstractBeginNode keySuccessor(int i) { + return successors.get(keySuccessors[i]); + } + + /** + * Returns the probability of the key at the given index. + */ + public double keyProbability(int i) { + return keyProbabilities[i]; + } + + /** + * Returns the index of the default (fall through) successor of this switch. + */ + public int defaultSuccessorIndex() { + return keySuccessors[keySuccessors.length - 1]; + } + + public AbstractBeginNode blockSuccessor(int i) { + return successors.get(i); + } + + public void setBlockSuccessor(int i, AbstractBeginNode s) { + successors.set(i, s); + } + + public int blockSuccessorCount() { + return successors.count(); + } + + /** + * Gets the successor corresponding to the default (fall through) case. + * + * @return the default successor + */ + public AbstractBeginNode defaultSuccessor() { + if (defaultSuccessorIndex() == -1) { + throw new GraalError("unexpected"); + } + return successors.get(defaultSuccessorIndex()); + } + + @Override + public AbstractBeginNode getPrimarySuccessor() { + return this.defaultSuccessor(); + } + + /** + * Delete all other successors except for the one reached by {@code survivingEdge}. + * + * @param tool + * @param survivingEdge index of the edge in the {@link SwitchNode#successors} list + */ + protected void killOtherSuccessors(SimplifierTool tool, int survivingEdge) { + for (Node successor : successors()) { + /* + * Deleting a branch change change the successors so reload the surviving successor each + * time. + */ + if (successor != blockSuccessor(survivingEdge)) { + tool.deleteBranch(successor); + } + } + tool.addToWorkList(blockSuccessor(survivingEdge)); + graph().removeSplit(this, blockSuccessor(survivingEdge)); + } +}