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     public static int max(final int a, final int b) {
  48         return (a >= b) ? a : b;
  49     }
  50 
  51     public static int min(final int a, final int b) {
  52         return (a <= b) ? a : b;
  53     }
  54 
  55     /**
  56      * Faster alternative to ceil(float) optimized for the integer domain
  57      * and supporting NaN and +/-Infinity.
  58      *
  59      * @param a a value.
  60      * @return the largest (closest to positive infinity) integer value
  61      * that less than or equal to the argument and is equal to a mathematical
  62      * integer.
  63      */
  64     public static int ceil_int(final float a) {
  65         final int intpart = (int) a;
  66 
  67         if (a <= intpart
  68                 || (CHECK_OVERFLOW && intpart == Integer.MAX_VALUE)
  69                 || CHECK_NAN && Float.isNaN(a)) {
  70             return intpart;
  71         }
  72         return intpart + 1;
  73     }
  74 
  75     /**
  76      * Faster alternative to floor(float) optimized for the integer domain
  77      * and supporting NaN and +/-Infinity.
  78      *
  79      * @param a a value.
  80      * @return the largest (closest to positive infinity) floating-point value
  81      * that less than or equal to the argument and is equal to a mathematical
  82      * integer.
  83      */
  84     public static int floor_int(final float a) {
  85         final int intpart = (int) a;
  86 
  87         if (a >= intpart
  88                 || (CHECK_OVERFLOW && intpart == Integer.MIN_VALUE)
  89                 || CHECK_NAN && Float.isNaN(a)) {
  90             return intpart;
  91         }
  92         return intpart - 1;
  93     }
  94 }