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 */ 23 package org.graalvm.compiler.replacements.nodes; 24 25 import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_1; 26 import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_1; 27 28 import org.graalvm.compiler.core.common.LIRKind; 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.nodeinfo.Verbosity; 33 import org.graalvm.compiler.nodes.FixedWithNextNode; 34 import org.graalvm.compiler.nodes.spi.LIRLowerable; 35 import org.graalvm.compiler.nodes.spi.NodeLIRBuilderTool; 36 37 import jdk.vm.ci.code.Register; 38 import jdk.vm.ci.meta.JavaKind; 39 import jdk.vm.ci.meta.Value; 40 41 /** 42 * Access the value of a specific register. 43 */ 44 @NodeInfo(nameTemplate = "ReadRegister %{p#register}", cycles = CYCLES_1, size = SIZE_1) 45 public final class ReadRegisterNode extends FixedWithNextNode implements LIRLowerable { 46 47 public static final NodeClass<ReadRegisterNode> TYPE = NodeClass.create(ReadRegisterNode.class); 48 /** 49 * The fixed register to access. 50 */ 51 protected final Register register; 52 53 /** 54 * When true, subsequent uses of this node use the fixed register; when false, the value is 55 * moved into a new virtual register so that the fixed register is not seen by uses. 56 */ 57 protected final boolean directUse; 58 59 /** 60 * When true, this node is also an implicit definition of the value for the register allocator, 61 * i.e., the register is an implicit incoming value; when false, the register must be defined in 62 * the same method or must be an register excluded from register allocation. 63 */ 64 protected final boolean incoming; 65 66 public ReadRegisterNode(Register register, JavaKind kind, boolean directUse, boolean incoming) { 67 super(TYPE, StampFactory.forKind(kind)); 68 assert register != null; 69 this.register = register; 70 this.directUse = directUse; 71 this.incoming = incoming; 72 } 73 74 public ReadRegisterNode(Register register, boolean directUse, boolean incoming) { 75 super(TYPE, StampFactory.forNodeIntrinsic()); 76 assert register != null; 77 this.register = register; 78 this.directUse = directUse; 79 this.incoming = incoming; 80 } 81 82 @Override 83 public void generate(NodeLIRBuilderTool generator) { 84 LIRKind kind = generator.getLIRGeneratorTool().getLIRKind(stamp()); 85 Value result = register.asValue(kind); 86 if (incoming) { 87 generator.getLIRGeneratorTool().emitIncomingValues(new Value[]{result}); 88 } 89 if (!directUse) { 90 result = generator.getLIRGeneratorTool().emitMove(result); 91 } 92 generator.setResult(this, result); 93 } 94 95 @Override 96 public String toString(Verbosity verbosity) { 97 if (verbosity == Verbosity.Name) { 98 return super.toString(Verbosity.Name) + "%" + register; 99 } else { 100 return super.toString(verbosity); 101 } 102 } 103 }