src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.nodes/src/org/graalvm/compiler/nodes/extended/MultiGuardNode.java
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.internal.vm.compiler/share/classes/org.graalvm.compiler.nodes/src/org/graalvm/compiler/nodes/extended/MultiGuardNode.java Thu Nov 15 09:04:07 2018 -0800
@@ -0,0 +1,113 @@
+/*
+ * Copyright (c) 2014, 2018, 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.InputType.Guard;
+import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_0;
+import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_0;
+
+import org.graalvm.compiler.core.common.type.StampFactory;
+import org.graalvm.compiler.graph.Node;
+import org.graalvm.compiler.graph.NodeClass;
+import org.graalvm.compiler.graph.NodeInputList;
+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.StructuredGraph;
+import org.graalvm.compiler.nodes.ValueNode;
+import org.graalvm.compiler.nodes.calc.FloatingNode;
+import org.graalvm.compiler.nodes.spi.LIRLowerable;
+import org.graalvm.compiler.nodes.spi.NodeLIRBuilderTool;
+import org.graalvm.compiler.nodes.util.GraphUtil;
+
+@NodeInfo(allowedUsageTypes = Guard, cycles = CYCLES_0, size = SIZE_0)
+public final class MultiGuardNode extends FloatingNode implements GuardingNode, LIRLowerable, Simplifiable, Node.ValueNumberable {
+ public static final NodeClass<MultiGuardNode> TYPE = NodeClass.create(MultiGuardNode.class);
+
+ @OptionalInput(Guard) NodeInputList<ValueNode> guards;
+
+ public MultiGuardNode(ValueNode... guards) {
+ super(TYPE, StampFactory.forVoid());
+ this.guards = new NodeInputList<>(this, guards);
+ }
+
+ @Override
+ public void generate(NodeLIRBuilderTool generator) {
+ }
+
+ @Override
+ public void simplify(SimplifierTool tool) {
+ if (usages().filter(node -> node instanceof ValueAnchorNode).isNotEmpty()) {
+ /*
+ * For ValueAnchorNode usages, we can optimize MultiGuardNodes away if they depend on
+ * zero or one floating nodes (as opposed to fixed nodes).
+ */
+ Node singleFloatingGuard = null;
+ for (ValueNode guard : guards) {
+ if (GraphUtil.isFloatingNode(guard)) {
+ if (singleFloatingGuard == null) {
+ singleFloatingGuard = guard;
+ } else if (singleFloatingGuard != guard) {
+ return;
+ }
+ }
+ }
+ for (Node usage : usages().snapshot()) {
+ if (usage instanceof ValueAnchorNode) {
+ usage.replaceFirstInput(this, singleFloatingGuard);
+ tool.addToWorkList(usage);
+ }
+ }
+ if (usages().isEmpty()) {
+ GraphUtil.killWithUnusedFloatingInputs(this);
+ }
+ }
+ }
+
+ public void addGuard(GuardingNode g) {
+ this.guards.add(g.asNode());
+ }
+
+ public static GuardingNode combine(GuardingNode first, GuardingNode second) {
+ if (first == null) {
+ return second;
+ } else if (second == null) {
+ return first;
+ } else {
+ StructuredGraph graph = first.asNode().graph();
+ return graph.unique(new MultiGuardNode(first.asNode(), second.asNode()));
+ }
+ }
+
+ public static GuardingNode addGuard(GuardingNode first, GuardingNode second) {
+ if (first instanceof MultiGuardNode && second != null) {
+ MultiGuardNode multi = (MultiGuardNode) first;
+ multi.addGuard(second);
+ return multi;
+ } else {
+ return combine(first, second);
+ }
+ }
+}