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