1 /* 2 * Copyright (c) 2011, 2016, 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.extended; 24 25 import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_2; 26 import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_1; 27 28 import org.graalvm.compiler.core.common.LocationIdentity; 29 import org.graalvm.compiler.core.common.type.StampFactory; 30 import org.graalvm.compiler.graph.NodeClass; 31 import org.graalvm.compiler.nodeinfo.NodeInfo; 32 import org.graalvm.compiler.nodes.ValueNode; 33 import org.graalvm.compiler.nodes.java.LoadFieldNode; 34 import org.graalvm.compiler.nodes.spi.Lowerable; 35 import org.graalvm.compiler.nodes.spi.LoweringTool; 36 import org.graalvm.compiler.nodes.spi.Virtualizable; 37 import org.graalvm.compiler.nodes.spi.VirtualizerTool; 38 import org.graalvm.compiler.nodes.virtual.VirtualObjectNode; 39 40 import jdk.vm.ci.meta.Assumptions; 41 import jdk.vm.ci.meta.JavaKind; 42 import jdk.vm.ci.meta.ResolvedJavaField; 43 44 /** 45 * Load of a value from a location specified as an offset relative to an object. No null check is 46 * performed before the load. 47 */ 48 @NodeInfo(cycles = CYCLES_2, size = SIZE_1) 49 public class UnsafeLoadNode extends UnsafeAccessNode implements Lowerable, Virtualizable { 50 public static final NodeClass<UnsafeLoadNode> TYPE = NodeClass.create(UnsafeLoadNode.class); 51 52 public UnsafeLoadNode(ValueNode object, ValueNode offset, JavaKind accessKind, LocationIdentity locationIdentity) { 53 super(TYPE, StampFactory.forKind(accessKind.getStackKind()), object, offset, accessKind, locationIdentity); 54 } 55 56 public UnsafeLoadNode(NodeClass<? extends UnsafeLoadNode> c, ValueNode object, ValueNode offset, JavaKind accessKind, LocationIdentity locationIdentity) { 57 super(c, StampFactory.forKind(accessKind.getStackKind()), object, offset, accessKind, locationIdentity); 58 } 59 60 @Override 61 public void lower(LoweringTool tool) { 62 tool.getLowerer().lower(this, tool); 63 } 64 65 @Override 66 public void virtualize(VirtualizerTool tool) { 67 ValueNode alias = tool.getAlias(object()); 68 if (alias instanceof VirtualObjectNode) { 69 VirtualObjectNode virtual = (VirtualObjectNode) alias; 70 ValueNode offsetValue = tool.getAlias(offset()); 71 if (offsetValue.isConstant()) { 72 long off = offsetValue.asJavaConstant().asLong(); 73 int entryIndex = virtual.entryIndexForOffset(off, accessKind()); 74 75 if (entryIndex != -1) { 76 ValueNode entry = tool.getEntry(virtual, entryIndex); 77 JavaKind entryKind = virtual.entryKind(entryIndex); 78 if (entry.getStackKind() == getStackKind() || entryKind == accessKind()) { 79 tool.replaceWith(entry); 80 } 81 } 82 } 83 } 84 } 85 86 @Override 87 protected ValueNode cloneAsFieldAccess(Assumptions assumptions, ResolvedJavaField field) { 88 return LoadFieldNode.create(assumptions, object(), field); 89 } 90 91 @Override 92 protected ValueNode cloneAsArrayAccess(ValueNode location, LocationIdentity identity) { 93 return new UnsafeLoadNode(object(), location, accessKind(), identity); 94 } 95 96 @NodeIntrinsic 97 public static native Object load(Object object, long offset, @ConstantNodeParameter JavaKind kind, @ConstantNodeParameter LocationIdentity locationIdentity); 98 }