1/*
2 * Public domain.
3 */
4
5#if defined(LIBM_SCCS) && !defined(lint)
6static char rcsid[] = "$NetBSD: s_isinff.c,v 1.3 1995/05/11 23:20:21 jtc Exp $";
7#endif
8
9/*
10 * isinff(x) returns 1 if x is inf, -1 if x is -inf, else 0;
11 * no branching!
12 */
13
14#include <math.h>
15#include <math_private.h>
16
17int
18__isinff (float x)
19{
20 int32_t ix,t;
21 GET_FLOAT_WORD(ix,x);
22 t = ix & 0x7fffffff;
23 t ^= 0x7f800000;
24 t |= -t;
25 return ~(t >> 31) & (ix >> 30);
26}
27hidden_def (__isinff)
28weak_alias (__isinff, isinff)
29

source code of glibc/sysdeps/ieee754/flt-32/s_isinff.c