newlib/libm/common/s_fmax.c

   1 /* Copyright (C) 2002 by  Red Hat, Incorporated. All rights reserved.
   2  *
   3  * Permission to use, copy, modify, and distribute this software
   4  * is freely granted, provided that this notice is preserved.
   5  */
   6 /*
   7 FUNCTION
   8 <<fmax>>, <<fmaxf>>---maximum
   9 INDEX
  10         fmax
  11 INDEX
  12         fmaxf
  13
  14 SYNOPSIS
  15         #include <math.h>
  16         double fmax(double <[x]>, double <[y]>);
  17         float fmaxf(float <[x]>, float <[y]>);
  18
  19 DESCRIPTION
  20 The <<fmax>> functions determine the maximum numeric value of their arguments.
  21 NaN arguments are treated as missing data:  if one argument is a NaN and the
  22 other numeric, then the <<fmax>> functions choose the numeric value.
  23
  24 RETURNS
  25 The <<fmax>> functions return the maximum numeric value of their arguments.
  26
  27 PORTABILITY
  28 ANSI C, POSIX.
  29
  30 */
  31
  32 #include "fdlibm.h"
  33
  34 #ifndef _DOUBLE_IS_32BITS
  35
  36 #ifdef __STDC__
  37         double fmax(double x, double y)
  38 #else
  39         double fmax(x,y)
  40         double x;
  41         double y;
  42 #endif
  43 {
  44   if (__fpclassifyd(x) == FP_NAN)
  45     return y;
  46   if (__fpclassifyd(y) == FP_NAN)
  47     return x;
  48
  49   return x > y ? x : y;
  50 }
  51
  52 #endif /* _DOUBLE_IS_32BITS */