lib/libm/src/s_isnanf.c

   1 /* s_isnanf.c -- float version of s_isnan.c.
   2  * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
   3  */
   4
   5 /*
   6  * ====================================================
   7  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
   8  *
   9  * Developed at SunPro, a Sun Microsystems, Inc. business.
  10  * Permission to use, copy, modify, and distribute this
  11  * software is freely granted, provided that this notice
  12  * is preserved.
  13  * ====================================================
  14  */
  15
  16 #include <sys/cdefs.h>
  17 #if defined(LIBM_SCCS) && !defined(lint)
  18 __RCSID("$NetBSD: s_isnanf.c,v 1.7 2002/05/26 22:01:56 wiz Exp $");
  19 #endif
  20
  21 /*
  22  * isnanf(x) returns 1 is x is nan, else 0;
  23  * no branching!
  24  */
  25
  26 #include "math.h"
  27 #include "math_private.h"
  28
  29 int
  30 isnanf(float x)
  31 {
  32         int32_t ix;
  33         GET_FLOAT_WORD(ix,x);
  34         ix &= 0x7fffffff;
  35         ix = 0x7f800000 - ix;
  36         return (int)(((u_int32_t)(ix))>>31);
  37 }