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 */ 23 package org.graalvm.compiler.replacements.nodes.arithmetic; 24 25 import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_2; 26 import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_2; 27 28 import java.util.function.BiFunction; 29 30 import org.graalvm.compiler.core.common.type.IntegerStamp; 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.graph.spi.CanonicalizerTool; 35 import org.graalvm.compiler.lir.gen.ArithmeticLIRGeneratorTool; 36 import org.graalvm.compiler.nodeinfo.NodeInfo; 37 import org.graalvm.compiler.nodes.ConstantNode; 38 import org.graalvm.compiler.nodes.ValueNode; 39 import org.graalvm.compiler.nodes.calc.BinaryNode; 40 import org.graalvm.compiler.nodes.spi.ArithmeticLIRLowerable; 41 import org.graalvm.compiler.nodes.spi.NodeLIRBuilderTool; 42 43 import jdk.vm.ci.meta.JavaKind; 44 import jdk.vm.ci.meta.Value; 45 46 @NodeInfo(shortName = "*H", cycles = CYCLES_2, size = SIZE_2) 47 public final class IntegerMulHighNode extends BinaryNode implements ArithmeticLIRLowerable { 48 public static final NodeClass<IntegerMulHighNode> TYPE = NodeClass.create(IntegerMulHighNode.class); 49 50 public IntegerMulHighNode(ValueNode x, ValueNode y) { 51 this((IntegerStamp) x.stamp().unrestricted(), x, y); 52 } 53 54 public IntegerMulHighNode(IntegerStamp stamp, ValueNode x, ValueNode y) { 55 super(TYPE, stamp, x, y); 56 } 57 58 /** 59 * Determines the minimum and maximum result of this node for the given inputs and returns the 60 * result of the given BiFunction on the minimum and maximum values. 61 */ 62 private <T> T processExtremes(Stamp forX, Stamp forY, BiFunction<Long, Long, T> op) { 63 IntegerStamp xStamp = (IntegerStamp) forX; 64 IntegerStamp yStamp = (IntegerStamp) forY; 65 66 JavaKind kind = getStackKind(); 67 assert kind == JavaKind.Int || kind == JavaKind.Long; 68 long[] xExtremes = {xStamp.lowerBound(), xStamp.upperBound()}; 69 long[] yExtremes = {yStamp.lowerBound(), yStamp.upperBound()}; 70 long min = Long.MAX_VALUE; 71 long max = Long.MIN_VALUE; 72 for (long a : xExtremes) { 73 for (long b : yExtremes) { 74 long result = kind == JavaKind.Int ? multiplyHigh((int) a, (int) b) : multiplyHigh(a, b); 75 min = Math.min(min, result); 76 max = Math.max(max, result); 77 } 78 } 79 return op.apply(min, max); 80 } 81 82 @Override 83 public Stamp foldStamp(Stamp stampX, Stamp stampY) { 84 return processExtremes(stampX, stampY, (min, max) -> StampFactory.forInteger(getStackKind(), min, max)); 85 } 86 87 @SuppressWarnings("cast") 88 @Override 89 public ValueNode canonical(CanonicalizerTool tool, ValueNode forX, ValueNode forY) { 90 return processExtremes(forX.stamp(), forY.stamp(), (min, max) -> min == (long) max ? ConstantNode.forIntegerKind(getStackKind(), min) : this); 91 } 92 93 @Override 94 public void generate(NodeLIRBuilderTool nodeValueMap, ArithmeticLIRGeneratorTool gen) { 95 Value a = nodeValueMap.operand(getX()); 96 Value b = nodeValueMap.operand(getY()); 97 nodeValueMap.setResult(this, gen.emitMulHigh(a, b)); 98 } 99 100 public static int multiplyHigh(int x, int y) { 101 long r = (long) x * (long) y; 102 return (int) (r >> 32); 103 } 104 105 public static long multiplyHigh(long x, long y) { 106 // Checkstyle: stop 107 long x0, y0, z0; 108 long x1, y1, z1, z2, t; 109 // Checkstyle: resume 110 111 x0 = x & 0xFFFFFFFFL; 112 x1 = x >> 32; 113 114 y0 = y & 0xFFFFFFFFL; 115 y1 = y >> 32; 116 117 z0 = x0 * y0; 118 t = x1 * y0 + (z0 >>> 32); 119 z1 = t & 0xFFFFFFFFL; 120 z2 = t >> 32; 121 z1 += x0 * y1; 122 123 return x1 * y1 + z2 + (z1 >> 32); 124 } 125 }