newlib/libm/ld/s_fmaxl.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   3  *
   4  * Copyright (c) 2004 David Schultz <das@FreeBSD.ORG>
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  */
  28
  29 #include <sys/cdefs.h>
  30 __FBSDID("$FreeBSD$");
  31
  32 #include <math.h>
  33
  34 #include "fpmath.h"
  35
  36 long double
  37 fmaxl(long double x, long double y)
  38 {
  39         union IEEEl2bits u[2];
  40
  41         u[0].e = x;
  42         mask_nbit_l(u[0]);
  43         u[1].e = y;
  44         mask_nbit_l(u[1]);
  45
  46         /* Check for NaNs to avoid raising spurious exceptions. */
  47         if (u[0].bits.exp == 32767 && (u[0].bits.manh | u[0].bits.manl) != 0)
  48                 return (y);
  49         if (u[1].bits.exp == 32767 && (u[1].bits.manh | u[1].bits.manl) != 0)
  50                 return (x);
  51
  52         /* Handle comparisons of signed zeroes. */
  53         if (u[0].bits.sign != u[1].bits.sign)
  54                 return (u[0].bits.sign ? y : x);
  55
  56         return (x > y ? x : y);
  57 }