1 /*
   2  * Copyright (c) 2015, 2016, 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.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package com.sun.marlin;
  27 
  28 /**
  29  * Faster Math ceil / floor routines derived from StrictMath
  30  */
  31 public final class FloatMath implements MarlinConst {
  32 
  33     // overflow / NaN handling enabled:
  34     static final boolean CHECK_OVERFLOW = true;
  35     static final boolean CHECK_NAN = true;
  36 
  37     private FloatMath() {
  38         // utility class
  39     }
  40 
  41     // faster inlined min/max functions in the branch prediction is high
  42     static float max(final float a, final float b) {
  43         // no NaN handling
  44         return (a >= b) ? a : b;
  45     }
  46 
  47     static double max(final double a, final double b) {
  48         // no NaN handling
  49         return (a >= b) ? a : b;
  50     }
  51 
  52     public static int max(final int a, final int b) {
  53         return (a >= b) ? a : b;
  54     }
  55 
  56     public static int min(final int a, final int b) {
  57         return (a <= b) ? a : b;
  58     }
  59 
  60     /**
  61      * Faster alternative to ceil(float) optimized for the integer domain
  62      * and supporting NaN and +/-Infinity.
  63      *
  64      * @param a a value.
  65      * @return the largest (closest to positive infinity) integer value
  66      * that less than or equal to the argument and is equal to a mathematical
  67      * integer.
  68      */
  69     public static int ceil_int(final float a) {
  70         final int intpart = (int) a;
  71 
  72         if (a <= intpart
  73                 || (CHECK_OVERFLOW && intpart == Integer.MAX_VALUE)
  74                 || CHECK_NAN && Float.isNaN(a)) {
  75             return intpart;
  76         }
  77         return intpart + 1;
  78     }
  79 
  80     /**
  81      * Faster alternative to ceil(double) optimized for the integer domain
  82      * and supporting NaN and +/-Infinity.
  83      *
  84      * @param a a value.
  85      * @return the largest (closest to positive infinity) integer value
  86      * that less than or equal to the argument and is equal to a mathematical
  87      * integer.
  88      */
  89     public static int ceil_int(final double a) {
  90         final int intpart = (int) a;
  91 
  92         if (a <= intpart
  93                 || (CHECK_OVERFLOW && intpart == Integer.MAX_VALUE)
  94                 || CHECK_NAN && Double.isNaN(a)) {
  95             return intpart;
  96         }
  97         return intpart + 1;
  98     }
  99 
 100     /**
 101      * Faster alternative to floor(float) optimized for the integer domain
 102      * and supporting NaN and +/-Infinity.
 103      *
 104      * @param a a value.
 105      * @return the largest (closest to positive infinity) floating-point value
 106      * that less than or equal to the argument and is equal to a mathematical
 107      * integer.
 108      */
 109     public static int floor_int(final float a) {
 110         final int intpart = (int) a;
 111 
 112         if (a >= intpart
 113                 || (CHECK_OVERFLOW && intpart == Integer.MIN_VALUE)
 114                 || CHECK_NAN && Float.isNaN(a)) {
 115             return intpart;
 116         }
 117         return intpart - 1;
 118     }
 119 
 120     /**
 121      * Faster alternative to floor(double) optimized for the integer domain
 122      * and supporting NaN and +/-Infinity.
 123      *
 124      * @param a a value.
 125      * @return the largest (closest to positive infinity) floating-point value
 126      * that less than or equal to the argument and is equal to a mathematical
 127      * integer.
 128      */
 129     public static int floor_int(final double a) {
 130         final int intpart = (int) a;
 131 
 132         if (a >= intpart
 133                 || (CHECK_OVERFLOW && intpart == Integer.MIN_VALUE)
 134                 || CHECK_NAN && Double.isNaN(a)) {
 135             return intpart;
 136         }
 137         return intpart - 1;
 138     }
 139 }