newlib/libm/common/s_fpclassify.c

   1 /* Copyright (C) 2002, 2007 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 #include "fdlibm.h"
   8
   9 int
  10 __fpclassifyd (double x)
  11 {
  12   __uint32_t msw, lsw;
  13
  14   EXTRACT_WORDS(msw,lsw,x);
  15
  16   if ((msw == 0x00000000 && lsw == 0x00000000) ||
  17       (msw == 0x80000000 && lsw == 0x00000000))
  18     return FP_ZERO;
  19   else if ((msw >= 0x00100000 && msw <= 0x7fefffff) ||
  20            (msw >= 0x80100000 && msw <= 0xffefffff))
  21     return FP_NORMAL;
  22   else if ((msw >= 0x00000000 && msw <= 0x000fffff) ||
  23            (msw >= 0x80000000 && msw <= 0x800fffff))
  24     /* zero is already handled above */
  25     return FP_SUBNORMAL;
  26   else if ((msw == 0x7ff00000 && lsw == 0x00000000) ||
  27            (msw == 0xfff00000 && lsw == 0x00000000))
  28     return FP_INFINITE;
  29   else
  30     return FP_NAN;
  31 }