1 /* 2 * Copyright (c) 2013, 2014, 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.replacements.nodes; 24 25 import org.graalvm.compiler.core.common.type.StampPair; 26 import org.graalvm.compiler.graph.Node; 27 import org.graalvm.compiler.graph.NodeClass; 28 import org.graalvm.compiler.graph.spi.Canonicalizable; 29 import org.graalvm.compiler.graph.spi.CanonicalizerTool; 30 import org.graalvm.compiler.nodeinfo.NodeInfo; 31 import org.graalvm.compiler.nodes.CallTargetNode.InvokeKind; 32 import org.graalvm.compiler.nodes.ConstantNode; 33 import org.graalvm.compiler.nodes.ValueNode; 34 35 import jdk.vm.ci.meta.JavaConstant; 36 import jdk.vm.ci.meta.MetaAccessProvider; 37 import jdk.vm.ci.meta.ResolvedJavaMethod; 38 39 /** 40 * This node class can be used to create {@link MacroNode}s for simple pure functions like 41 * {@link System#identityHashCode(Object)}. 42 */ 43 @NodeInfo 44 public abstract class PureFunctionMacroNode extends MacroStateSplitNode implements Canonicalizable { 45 46 public static final NodeClass<PureFunctionMacroNode> TYPE = NodeClass.create(PureFunctionMacroNode.class); 47 48 public PureFunctionMacroNode(NodeClass<? extends MacroNode> c, InvokeKind invokeKind, ResolvedJavaMethod targetMethod, int bci, StampPair returnStamp, ValueNode... arguments) { 49 super(c, invokeKind, targetMethod, bci, returnStamp, arguments); 50 } 51 52 /** 53 * This method should return either a constant that represents the result of the function, or 54 * null if no such result could be determined. 55 */ 56 protected abstract JavaConstant evaluate(JavaConstant param, MetaAccessProvider metaAccess); 57 58 @Override 59 public Node canonical(CanonicalizerTool tool) { 60 if (tool.allUsagesAvailable() && hasNoUsages()) { 61 return null; 62 } else { 63 ValueNode param = arguments.get(0); 64 if (param.isConstant()) { 65 JavaConstant constant = evaluate(param.asJavaConstant(), tool.getMetaAccess()); 66 if (constant != null) { 67 return ConstantNode.forConstant(constant, tool.getMetaAccess()); 68 } 69 } 70 } 71 return this; 72 } 73 }