lib/libm/src/s_isinf.c

   1 /*
   2  * Written by J.T. Conklin <jtc@NetBSD.org>.
   3  * Public domain.
   4  */
   5
   6 #include <sys/cdefs.h>
   7 #if defined(LIBM_SCCS) && !defined(lint)
   8 __RCSID("$NetBSD: s_isinf.c,v 1.6 2003/07/26 19:25:05 salo Exp $");
   9 #endif
  10
  11 /*
  12  * isinf(x) returns 1 is x is inf, else 0;
  13  * no branching!
  14  */
  15
  16 #include "math.h"
  17 #include "math_private.h"
  18
  19 int
  20 isinf(double x)
  21 {
  22         int32_t hx,lx;
  23         EXTRACT_WORDS(hx,lx,x);
  24         hx &= 0x7fffffff;
  25         hx ^= 0x7ff00000;
  26         hx |= lx;
  27         return (hx == 0);
  28 }