1 /* 2 * Copyright (c) 2013, 2015, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 package org.graalvm.compiler.nodes; 24 25 import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_0; 26 import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_0; 27 28 import org.graalvm.compiler.graph.Node; 29 import org.graalvm.compiler.graph.NodeClass; 30 import org.graalvm.compiler.graph.spi.Canonicalizable; 31 import org.graalvm.compiler.graph.spi.CanonicalizerTool; 32 import org.graalvm.compiler.nodeinfo.NodeInfo; 33 import org.graalvm.compiler.nodes.extended.GuardingNode; 34 import org.graalvm.compiler.nodes.spi.LIRLowerable; 35 import org.graalvm.compiler.nodes.spi.NodeLIRBuilderTool; 36 import org.graalvm.compiler.nodes.spi.ValueProxy; 37 import org.graalvm.compiler.nodes.spi.Virtualizable; 38 import org.graalvm.compiler.nodes.spi.VirtualizerTool; 39 import org.graalvm.compiler.nodes.virtual.VirtualObjectNode; 40 41 import jdk.vm.ci.meta.JavaKind; 42 43 /** 44 * A node that changes the type of its input, usually narrowing it. For example, a GuardedValueNode 45 * is used to keep the nodes depending on guards inside a loop during speculative guard movement. 46 * 47 * A GuardedValueNode will only go away if its guard is null or {@link StructuredGraph#start()}. 48 */ 49 @NodeInfo(cycles = CYCLES_0, size = SIZE_0) 50 public final class GuardedValueNode extends FloatingGuardedNode implements LIRLowerable, Virtualizable, Canonicalizable, ValueProxy { 51 52 public static final NodeClass<GuardedValueNode> TYPE = NodeClass.create(GuardedValueNode.class); 53 @Input ValueNode object; 54 55 public GuardedValueNode(ValueNode object, GuardingNode guard) { 56 super(TYPE, object.stamp(), guard); 57 this.object = object; 58 } 59 60 public ValueNode object() { 61 return object; 62 } 63 64 @Override 65 public void generate(NodeLIRBuilderTool generator) { 66 if (object.getStackKind() != JavaKind.Void && object.getStackKind() != JavaKind.Illegal) { 67 generator.setResult(this, generator.operand(object)); 68 } 69 } 70 71 @Override 72 public boolean inferStamp() { 73 return updateStamp(object().stamp()); 74 } 75 76 @Override 77 public void virtualize(VirtualizerTool tool) { 78 ValueNode alias = tool.getAlias(object()); 79 if (alias instanceof VirtualObjectNode) { 80 tool.replaceWithVirtual((VirtualObjectNode) alias); 81 } 82 } 83 84 @Override 85 public Node canonical(CanonicalizerTool tool) { 86 if (getGuard() == null) { 87 if (stamp().equals(object().stamp())) { 88 return object(); 89 } else { 90 return new PiNode(object(), stamp()); 91 } 92 } 93 return this; 94 } 95 96 @Override 97 public ValueNode getOriginalNode() { 98 return object; 99 } 100 }