1/* 2 * Copyright (c) 2012, 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 */ 23package org.graalvm.compiler.replacements.nodes; 24 25import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_0; 26import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_0; 27 28import org.graalvm.compiler.core.common.LIRKind; 29import org.graalvm.compiler.core.common.type.Stamp; 30import org.graalvm.compiler.core.common.type.StampFactory; 31import org.graalvm.compiler.graph.NodeClass; 32import org.graalvm.compiler.nodeinfo.NodeInfo; 33import org.graalvm.compiler.nodeinfo.Verbosity; 34import org.graalvm.compiler.nodes.FixedWithNextNode; 35import org.graalvm.compiler.nodes.spi.LIRLowerable; 36import org.graalvm.compiler.nodes.spi.NodeLIRBuilderTool; 37 38import jdk.vm.ci.code.Register; 39import jdk.vm.ci.meta.JavaKind; 40import jdk.vm.ci.meta.Value; 41 42/** 43 * Access the value of a specific register. 44 */ 45@NodeInfo(nameTemplate = "ReadRegister %{p#register}", cycles = CYCLES_0, size = SIZE_0) 46public final class ReadRegisterNode extends FixedWithNextNode implements LIRLowerable { 47 48 public static final NodeClass<ReadRegisterNode> TYPE = NodeClass.create(ReadRegisterNode.class); 49 /** 50 * The fixed register to access. 51 */ 52 protected final Register register; 53 54 /** 55 * When true, subsequent uses of this node use the fixed register; when false, the value is 56 * moved into a new virtual register so that the fixed register is not seen by uses. 57 */ 58 protected final boolean directUse; 59 60 /** 61 * When true, this node is also an implicit definition of the value for the register allocator, 62 * i.e., the register is an implicit incoming value; when false, the register must be defined in 63 * the same method or must be an register excluded from register allocation. 64 */ 65 protected final boolean incoming; 66 67 public ReadRegisterNode(Register register, JavaKind kind, boolean directUse, boolean incoming) { 68 super(TYPE, StampFactory.forKind(kind)); 69 assert register != null; 70 this.register = register; 71 this.directUse = directUse; 72 this.incoming = incoming; 73 } 74 75 public ReadRegisterNode(@InjectedNodeParameter Stamp stamp, Register register, boolean directUse, boolean incoming) { 76 super(TYPE, stamp); 77 assert register != null; 78 this.register = register; 79 this.directUse = directUse; 80 this.incoming = incoming; 81 } 82 83 @Override 84 public void generate(NodeLIRBuilderTool generator) { 85 LIRKind kind = generator.getLIRGeneratorTool().getLIRKind(stamp()); 86 Value result = register.asValue(kind); 87 if (incoming) { 88 generator.getLIRGeneratorTool().emitIncomingValues(new Value[]{result}); 89 } 90 if (!directUse) { 91 result = generator.getLIRGeneratorTool().emitMove(result); 92 } 93 generator.setResult(this, result); 94 } 95 96 @Override 97 public String toString(Verbosity verbosity) { 98 if (verbosity == Verbosity.Name) { 99 return super.toString(Verbosity.Name) + "%" + register; 100 } else { 101 return super.toString(verbosity); 102 } 103 } 104} 105