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/*
 * Written by J.T. Conklin <jtc@netbsd.org>.
 * Changed to return -1 for -Inf by Ulrich Drepper <drepper@cygnus.com>.
 * Public domain.
 */

/*
 * isinf(x) returns 1 is x is inf, -1 if x is -inf, else 0;
 * no branching!
 */

#include <math.h>
#include <math_private.h>
#include <ldbl-classify-compat.h>
#include <shlib-compat.h>

int
__isinf (double x)
{
  int64_t ix;
  EXTRACT_WORDS64 (ix,x);
  int64_t t = ix & UINT64_C (0x7fffffffffffffff);
  t ^= UINT64_C (0x7ff0000000000000);
  t |= -t;
  return ~(t >> 63) & (ix >> 62);
}
hidden_def (__isinf)
weak_alias (__isinf, isinf)
#ifdef NO_LONG_DOUBLE
# if LDBL_CLASSIFY_COMPAT && SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_23)
compat_symbol (libc, __isinf, __isinfl, GLIBC_2_0);
# endif
weak_alias (__isinf, isinfl)
#endif