1 /* 2 * Copyright (c) 2011, 2011, 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 jdk.internal.jvmci.code; 24 25 import java.math.*; 26 27 //JaCoCo Exclude 28 29 /** 30 * Utilities for unsigned comparisons. All methods have correct, but slow, standard Java 31 * implementations so that they can be used with compilers not supporting the intrinsics. 32 */ 33 public class UnsignedMath { 34 35 private static final long MASK = 0xffffffffL; 36 37 /** 38 * Unsigned comparison aboveThan for two numbers. 39 */ 40 public static boolean aboveThan(int a, int b) { 41 return (a & MASK) > (b & MASK); 42 } 43 44 /** 45 * Unsigned comparison aboveOrEqual for two numbers. 46 */ 47 public static boolean aboveOrEqual(int a, int b) { 48 return (a & MASK) >= (b & MASK); 49 } 50 51 /** 52 * Unsigned comparison belowThan for two numbers. 53 */ 54 public static boolean belowThan(int a, int b) { 55 return (a & MASK) < (b & MASK); 56 } 57 58 /** 59 * Unsigned comparison belowOrEqual for two numbers. 60 */ 61 public static boolean belowOrEqual(int a, int b) { 62 return (a & MASK) <= (b & MASK); 63 } 64 65 /** 66 * Unsigned comparison aboveThan for two numbers. 67 */ 68 public static boolean aboveThan(long a, long b) { 69 return (a > b) ^ ((a < 0) != (b < 0)); 70 } 71 72 /** 73 * Unsigned comparison aboveOrEqual for two numbers. 74 */ 75 public static boolean aboveOrEqual(long a, long b) { 76 return (a >= b) ^ ((a < 0) != (b < 0)); 77 } 78 79 /** 80 * Unsigned comparison belowThan for two numbers. 81 */ 82 public static boolean belowThan(long a, long b) { 83 return (a < b) ^ ((a < 0) != (b < 0)); 84 } 85 86 /** 87 * Unsigned comparison belowOrEqual for two numbers. 88 */ 89 public static boolean belowOrEqual(long a, long b) { 90 return (a <= b) ^ ((a < 0) != (b < 0)); 91 } 92 93 /** 94 * Unsigned division for two numbers. 95 */ 96 public static int divide(int a, int b) { 97 return (int) ((a & MASK) / (b & MASK)); 98 } 99 100 /** 101 * Unsigned remainder for two numbers. 102 */ 103 public static int remainder(int a, int b) { 104 return (int) ((a & MASK) % (b & MASK)); 105 } 106 107 /** 108 * Unsigned division for two numbers. 109 */ 110 public static long divide(long a, long b) { 111 return bi(a).divide(bi(b)).longValue(); 112 } 113 114 /** 115 * Unsigned remainder for two numbers. 116 */ 117 public static long remainder(long a, long b) { 118 return bi(a).remainder(bi(b)).longValue(); 119 } 120 121 private static BigInteger bi(long unsigned) { 122 return unsigned >= 0 ? BigInteger.valueOf(unsigned) : BigInteger.valueOf(unsigned & 0x7fffffffffffffffL).setBit(63); 123 } 124 }