toolchain/gcc/newlib/libm/mathfp/sf_isnan.c

   1
   2 /* @(#)z_isnanf.c 1.0 98/08/13 */
   3 /******************************************************************
   4  * isnanf
   5  *
   6  * Input:
   7  *   x - pointer to a floating point value
   8  *
   9  * Output:
  10  *   An integer that indicates if the number is NaN.
  11  *
  12  * Description:
  13  *   This routine returns an integer that indicates if the number
  14  *   passed in is NaN (1) or is finite (0).
  15  *
  16  *****************************************************************/
  17
  18 #include "fdlibm.h"
  19 #include "zmath.h"
  20
  21 int
  22 _DEFUN (isnanf, (float),
  23         float x)
  24 {
  25   __int32_t wx;
  26   int exp;
  27
  28   GET_FLOAT_WORD (wx, x);
  29   exp = (wx & 0x7f800000) >> 23;
  30
  31   if ((exp == 0x7f8) && (wx & 0x7fffff))
  32     return (1);
  33   else
  34     return (0);
  35 }
  36
  37
  38 #ifdef _DOUBLE_IS_32BITS
  39
  40 int
  41 _DEFUN (isnan, (double),
  42         double x)
  43 {
  44   return isnanf((float) x);
  45 }
  46
  47 #endif /* defined(_DOUBLE_IS_32BITS) */
  48