sysdeps/libm-ieee754/s_isinf.c

   1 /*
   2  * Written by J.T. Conklin <jtc@netbsd.org>.
   3  * Public domain.
   4  */
   5
   6 #if defined(LIBM_SCCS) && !defined(lint)
   7 static char rcsid[] = "$NetBSD: s_isinf.c,v 1.3 1995/05/11 23:20:14 jtc Exp $";
   8 #endif
   9
  10 /*
  11  * isinf(x) returns 1 is x is inf, else 0;
  12  * no branching!
  13  */
  14
  15 #include "math.h"
  16 #include "math_private.h"
  17
  18 #ifdef __STDC__
  19         int __isinf(double x)
  20 #else
  21         int __isinf(x)
  22         double x;
  23 #endif
  24 {
  25         int32_t hx,lx;
  26         EXTRACT_WORDS(hx,lx,x);
  27         hx &= 0x7fffffff;
  28         hx ^= 0x7ff00000;
  29         hx |= lx;
  30         return (hx == 0);
  31 }
  32 weak_alias (__isinf, isinf)
  33 #ifdef NO_LONG_DOUBLE
  34 strong_alias (__isinf, __isinfl)
  35 weak_alias (__isinf, isinfl)
  36 #endif