1 | /* |
2 | * Written by J.T. Conklin <jtc@netbsd.org>. |
3 | * Changed to return -1 for -Inf by Ulrich Drepper <drepper@cygnus.com>. |
4 | * Public domain. |
5 | */ |
6 | |
7 | /* |
8 | * isinf(x) returns 1 is x is inf, -1 if x is -inf, else 0; |
9 | * no branching! |
10 | */ |
11 | |
12 | #include <math.h> |
13 | #include <math_private.h> |
14 | #include <shlib-compat.h> |
15 | |
16 | int |
17 | __isinf (double x) |
18 | { |
19 | int64_t ix; |
20 | EXTRACT_WORDS64(ix,x); |
21 | int64_t t = ix & UINT64_C(0x7fffffffffffffff); |
22 | t ^= UINT64_C(0x7ff0000000000000); |
23 | t |= -t; |
24 | return ~(t >> 63) & (ix >> 62); |
25 | } |
26 | hidden_def (__isinf) |
27 | weak_alias (__isinf, isinf) |
28 | #ifdef NO_LONG_DOUBLE |
29 | # if defined LDBL_CLASSIFY_COMPAT && SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_23) |
30 | compat_symbol (libc, __isinf, __isinfl, GLIBC_2_0); |
31 | # endif |
32 | weak_alias (__isinf, isinfl) |
33 | #endif |
34 | |