1 /* 2 * Copyright (c) 2014, 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.hotspot.replacements; 24 25 import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_4; 26 import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_1; 27 28 import org.graalvm.compiler.core.common.type.StampFactory; 29 import org.graalvm.compiler.core.common.type.TypeReference; 30 import org.graalvm.compiler.graph.Node; 31 import org.graalvm.compiler.graph.NodeClass; 32 import org.graalvm.compiler.graph.spi.Canonicalizable; 33 import org.graalvm.compiler.graph.spi.CanonicalizerTool; 34 import org.graalvm.compiler.hotspot.word.KlassPointer; 35 import org.graalvm.compiler.nodeinfo.NodeInfo; 36 import org.graalvm.compiler.nodes.ConstantNode; 37 import org.graalvm.compiler.nodes.FloatingGuardedNode; 38 import org.graalvm.compiler.nodes.ValueNode; 39 import org.graalvm.compiler.nodes.calc.ConvertNode; 40 import org.graalvm.compiler.nodes.spi.Lowerable; 41 import org.graalvm.compiler.nodes.spi.LoweringTool; 42 43 import jdk.vm.ci.meta.Constant; 44 import jdk.vm.ci.meta.ConstantReflectionProvider; 45 import jdk.vm.ci.meta.JavaConstant; 46 import jdk.vm.ci.meta.MetaAccessProvider; 47 import jdk.vm.ci.meta.ResolvedJavaType; 48 49 /** 50 * Read {@code Klass::_java_mirror} and incorporate non-null type information into stamp. This is 51 * also used by {@link ClassGetHubNode} to eliminate chains of {@code klass._java_mirror._klass}. 52 */ 53 @NodeInfo(cycles = CYCLES_4, size = SIZE_1) 54 public final class HubGetClassNode extends FloatingGuardedNode implements Lowerable, Canonicalizable, ConvertNode { 55 public static final NodeClass<HubGetClassNode> TYPE = NodeClass.create(HubGetClassNode.class); 56 @Input protected ValueNode hub; 57 58 public HubGetClassNode(@InjectedNodeParameter MetaAccessProvider metaAccess, ValueNode hub) { 59 super(TYPE, StampFactory.objectNonNull(TypeReference.createWithoutAssumptions(metaAccess.lookupJavaType(Class.class))), null); 60 this.hub = hub; 61 } 62 63 public ValueNode getHub() { 64 return hub; 65 } 66 67 @Override 68 public Node canonical(CanonicalizerTool tool) { 69 if (tool.allUsagesAvailable() && hasNoUsages()) { 70 return null; 71 } else { 72 MetaAccessProvider metaAccess = tool.getMetaAccess(); 73 if (metaAccess != null && hub.isConstant()) { 74 ResolvedJavaType exactType = tool.getConstantReflection().asJavaType(hub.asConstant()); 75 if (exactType != null) { 76 return ConstantNode.forConstant(tool.getConstantReflection().asJavaClass(exactType), metaAccess); 77 } 78 } 79 return this; 80 } 81 } 82 83 @Override 84 public void lower(LoweringTool tool) { 85 tool.getLowerer().lower(this, tool); 86 } 87 88 @NodeIntrinsic 89 public static native Class<?> readClass(KlassPointer hub); 90 91 @Override 92 public ValueNode getValue() { 93 return hub; 94 } 95 96 @Override 97 public Constant convert(Constant c, ConstantReflectionProvider constantReflection) { 98 if (JavaConstant.NULL_POINTER.equals(c)) { 99 return c; 100 } 101 return constantReflection.asJavaClass(constantReflection.asJavaType(c)); 102 } 103 104 @Override 105 public Constant reverse(Constant c, ConstantReflectionProvider constantReflection) { 106 if (JavaConstant.NULL_POINTER.equals(c)) { 107 return c; 108 } 109 ResolvedJavaType type = constantReflection.asJavaType(c); 110 if (type.isPrimitive()) { 111 return JavaConstant.NULL_POINTER; 112 } else { 113 return constantReflection.asObjectHub(type); 114 } 115 } 116 117 @Override 118 public boolean isLossless() { 119 /* 120 * Any concrete Klass* has a corresponding java.lang.Class 121 */ 122 return true; 123 } 124 }