libquadmath/math/isinfq.c

   1 /*
   2  * Written by J.T. Conklin <jtc@netbsd.org>.
   3  * Change for long double by Jakub Jelinek <jj@ultra.linux.cz>
   4  * Public domain.
   5  */
   6
   7 #if defined(LIBM_SCCS) && !defined(lint)
   8 static char rcsid[] = "$NetBSD: $";
   9 #endif
  10
  11 /*
  12  * isinfq(x) returns 1 if x is inf, -1 if x is -inf, else 0;
  13  * no branching!
  14  */
  15
  16 #include "quadmath-imp.h"
  17
  18 int
  19 isinfq (__float128 x)
  20 {
  21         int64_t hx,lx;
  22         GET_FLT128_WORDS64(hx,lx,x);
  23         lx |= (hx & 0x7fffffffffffffffLL) ^ 0x7fff000000000000LL;
  24         lx |= -lx;
  25         return ~(lx >> 63) & (hx >> 62);
  26 }