sysdeps/ieee754/dbl-64/s_finite.c

   1 /* @(#)s_finite.c 5.1 93/09/24 */
   2 /*
   3  * ====================================================
   4  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
   5  *
   6  * Developed at SunPro, a Sun Microsystems, Inc. business.
   7  * Permission to use, copy, modify, and distribute this
   8  * software is freely granted, provided that this notice
   9  * is preserved.
  10  * ====================================================
  11  */
  12
  13 #if defined(LIBM_SCCS) && !defined(lint)
  14 static char rcsid[] = "$NetBSD: s_finite.c,v 1.8 1995/05/10 20:47:17 jtc Exp $";
  15 #endif
  16
  17 /*
  18  * finite(x) returns 1 is x is finite, else 0;
  19  * no branching!
  20  */
  21
  22 #include <math.h>
  23 #include <math_private.h>
  24
  25 #undef __finite
  26
  27 #ifndef FINITE
  28 # define FINITE __finite
  29 #endif
  30
  31 int FINITE(double x)
  32 {
  33   int32_t hx;
  34   GET_HIGH_WORD (hx, x);
  35   return (int) ((u_int32_t) ((hx & 0x7fffffff) - 0x7ff00000) >> 31);
  36 }
  37 hidden_def (__finite)
  38 weak_alias (__finite, finite)
  39 #ifdef NO_LONG_DOUBLE
  40 strong_alias (__finite, __finitel)
  41 weak_alias (__finite, finitel)
  42 #endif