1/*
2 * Public domain.
3 */
4
5/*
6 * isinf(x) returns 1 is x is inf, -1 if x is -inf, else 0;
7 * no branching!
8 */
9
10#include <math.h>
11#include <math_private.h>
12#include <ldbl-classify-compat.h>
13#include <shlib-compat.h>
14
15int
16__isinf (double x)
17{
18 int64_t ix;
19 EXTRACT_WORDS64 (ix,x);
20 int64_t t = ix & UINT64_C (0x7fffffffffffffff);
21 t ^= UINT64_C (0x7ff0000000000000);
22 t |= -t;
23 return ~(t >> 63) & (ix >> 62);
24}
25hidden_def (__isinf)
26weak_alias (__isinf, isinf)
27#ifdef NO_LONG_DOUBLE
28# if LDBL_CLASSIFY_COMPAT && SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_23)
29compat_symbol (libc, __isinf, __isinfl, GLIBC_2_0);
30# endif
31weak_alias (__isinf, isinfl)
32#endif
33