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 */ 23package org.graalvm.compiler.nodes.calc; 24 25import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_1; 26 27import org.graalvm.compiler.core.common.type.ArithmeticOpTable; 28import org.graalvm.compiler.core.common.type.ArithmeticOpTable.IntegerConvertOp; 29import org.graalvm.compiler.core.common.type.ArithmeticOpTable.IntegerConvertOp.Narrow; 30import org.graalvm.compiler.core.common.type.ArithmeticOpTable.IntegerConvertOp.SignExtend; 31import org.graalvm.compiler.core.common.type.IntegerStamp; 32import org.graalvm.compiler.core.common.type.PrimitiveStamp; 33import org.graalvm.compiler.graph.NodeClass; 34import org.graalvm.compiler.graph.spi.CanonicalizerTool; 35import org.graalvm.compiler.lir.gen.ArithmeticLIRGeneratorTool; 36import org.graalvm.compiler.nodeinfo.NodeInfo; 37import org.graalvm.compiler.nodes.ValueNode; 38import org.graalvm.compiler.nodes.spi.NodeLIRBuilderTool; 39 40/** 41 * The {@code SignExtendNode} converts an integer to a wider integer using sign extension. 42 */ 43@NodeInfo(cycles = CYCLES_1) 44public final class SignExtendNode extends IntegerConvertNode<SignExtend, Narrow> { 45 46 public static final NodeClass<SignExtendNode> TYPE = NodeClass.create(SignExtendNode.class); 47 48 public SignExtendNode(ValueNode input, int resultBits) { 49 this(input, PrimitiveStamp.getBits(input.stamp()), resultBits); 50 assert 0 < PrimitiveStamp.getBits(input.stamp()) && PrimitiveStamp.getBits(input.stamp()) <= resultBits; 51 } 52 53 public SignExtendNode(ValueNode input, int inputBits, int resultBits) { 54 super(TYPE, ArithmeticOpTable::getSignExtend, ArithmeticOpTable::getNarrow, inputBits, resultBits, input); 55 } 56 57 public static ValueNode create(ValueNode input, int resultBits) { 58 return create(input, PrimitiveStamp.getBits(input.stamp()), resultBits); 59 } 60 61 public static ValueNode create(ValueNode input, int inputBits, int resultBits) { 62 IntegerConvertOp<SignExtend> signExtend = ArithmeticOpTable.forStamp(input.stamp()).getSignExtend(); 63 ValueNode synonym = findSynonym(signExtend, input, inputBits, resultBits, signExtend.foldStamp(inputBits, resultBits, input.stamp())); 64 if (synonym != null) { 65 return synonym; 66 } 67 return canonical(null, input, inputBits, resultBits); 68 } 69 70 @Override 71 public boolean isLossless() { 72 return true; 73 } 74 75 @Override 76 public ValueNode canonical(CanonicalizerTool tool, ValueNode forValue) { 77 ValueNode ret = super.canonical(tool, forValue); 78 if (ret != this) { 79 return ret; 80 } 81 82 return canonical(this, forValue, getInputBits(), getResultBits()); 83 } 84 85 private static ValueNode canonical(SignExtendNode self, ValueNode forValue, int inputBits, int resultBits) { 86 if (forValue instanceof SignExtendNode) { 87 // sxxx -(sign-extend)-> ssss sxxx -(sign-extend)-> ssssssss sssssxxx 88 // ==> sxxx -(sign-extend)-> ssssssss sssssxxx 89 SignExtendNode other = (SignExtendNode) forValue; 90 return SignExtendNode.create(other.getValue(), other.getInputBits(), resultBits); 91 } else if (forValue instanceof ZeroExtendNode) { 92 ZeroExtendNode other = (ZeroExtendNode) forValue; 93 if (other.getResultBits() > other.getInputBits()) { 94 // sxxx -(zero-extend)-> 0000 sxxx -(sign-extend)-> 00000000 0000sxxx 95 // ==> sxxx -(zero-extend)-> 00000000 0000sxxx 96 return ZeroExtendNode.create(other.getValue(), other.getInputBits(), resultBits); 97 } 98 } 99 100 if (forValue.stamp() instanceof IntegerStamp) { 101 IntegerStamp inputStamp = (IntegerStamp) forValue.stamp(); 102 if ((inputStamp.upMask() & (1L << (inputBits - 1))) == 0L) { 103 // 0xxx -(sign-extend)-> 0000 0xxx 104 // ==> 0xxx -(zero-extend)-> 0000 0xxx 105 return ZeroExtendNode.create(forValue, inputBits, resultBits); 106 } 107 } 108 109 return self != null ? self : new SignExtendNode(forValue, inputBits, resultBits); 110 } 111 112 @Override 113 public void generate(NodeLIRBuilderTool nodeValueMap, ArithmeticLIRGeneratorTool gen) { 114 nodeValueMap.setResult(this, gen.emitSignExtend(nodeValueMap.operand(getValue()), getInputBits(), getResultBits())); 115 } 116 117 @Override 118 public boolean mayNullCheckSkipConversion() { 119 return true; 120 } 121} 122