1 /* 2 * Copyright (c) 2012, 2018, 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 24 25 package org.graalvm.compiler.replacements.nodes; 26 27 import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_0; 28 import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_0; 29 30 import org.graalvm.compiler.core.common.LIRKind; 31 import org.graalvm.compiler.core.common.type.Stamp; 32 import org.graalvm.compiler.core.common.type.StampFactory; 33 import org.graalvm.compiler.graph.NodeClass; 34 import org.graalvm.compiler.nodeinfo.NodeInfo; 35 import org.graalvm.compiler.nodeinfo.Verbosity; 36 import org.graalvm.compiler.nodes.FixedWithNextNode; 37 import org.graalvm.compiler.nodes.NodeView; 38 import org.graalvm.compiler.nodes.spi.LIRLowerable; 39 import org.graalvm.compiler.nodes.spi.NodeLIRBuilderTool; 40 41 import jdk.vm.ci.code.Register; 42 import jdk.vm.ci.meta.JavaKind; 43 import jdk.vm.ci.meta.Value; 44 45 /** 46 * Access the value of a specific register. 47 */ 48 @NodeInfo(nameTemplate = "ReadRegister %{p#register}", cycles = CYCLES_0, size = SIZE_0) 49 public final class ReadRegisterNode extends FixedWithNextNode implements LIRLowerable { 50 51 public static final NodeClass<ReadRegisterNode> TYPE = NodeClass.create(ReadRegisterNode.class); 52 /** 53 * The fixed register to access. 54 */ 55 protected final Register register; 56 57 /** 58 * When true, subsequent uses of this node use the fixed register; when false, the value is 59 * moved into a new virtual register so that the fixed register is not seen by uses. 60 */ 61 protected final boolean directUse; 62 63 /** 64 * When true, this node is also an implicit definition of the value for the register allocator, 65 * i.e., the register is an implicit incoming value; when false, the register must be defined in 66 * the same method or must be an register excluded from register allocation. 67 */ 68 protected final boolean incoming; 69 70 public ReadRegisterNode(Register register, JavaKind kind, boolean directUse, boolean incoming) { 71 super(TYPE, StampFactory.forKind(kind)); 72 assert register != null; 73 this.register = register; 74 this.directUse = directUse; 75 this.incoming = incoming; 76 } 77 78 public ReadRegisterNode(@InjectedNodeParameter Stamp stamp, Register register, boolean directUse, boolean incoming) { 79 super(TYPE, stamp); 80 assert register != null; 81 this.register = register; 82 this.directUse = directUse; 83 this.incoming = incoming; 84 } 85 86 @Override 87 public void generate(NodeLIRBuilderTool generator) { 88 LIRKind kind = generator.getLIRGeneratorTool().getLIRKind(stamp(NodeView.DEFAULT)); 89 Value result = register.asValue(kind); 90 if (incoming) { 91 generator.getLIRGeneratorTool().emitIncomingValues(new Value[]{result}); 92 } 93 if (!directUse) { 94 result = generator.getLIRGeneratorTool().emitReadRegister(register, kind); 95 } 96 generator.setResult(this, result); 97 } 98 99 @Override 100 public String toString(Verbosity verbosity) { 101 if (verbosity == Verbosity.Name) { 102 return super.toString(Verbosity.Name) + "%" + register; 103 } else { 104 return super.toString(verbosity); 105 } 106 } 107 }