1 | /* |
2 | * Public domain. |
3 | */ |
4 | |
5 | #if defined(LIBM_SCCS) && !defined(lint) |
6 | static 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 | |
17 | int |
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 | } |
27 | hidden_def (__isinff) |
28 | weak_alias (__isinff, isinff) |
29 | |