2 * From: @(#)s_ilogb.c 5.1 93/09/24
3 * ====================================================
4 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
6 * Developed at SunPro, a Sun Microsystems, Inc. business.
7 * Permission to use, copy, modify, and distribute this
8 * software is freely granted, provided that this notice
10 * ====================================================
13 #include <sys/cdefs.h>
14 __FBSDID("$FreeBSD$");
30 if (u.bits.exp == 0) {
31 if ((u.bits.manl | u.bits.manh) == 0)
34 if (u.bits.manh == 0) {
35 m = 1lu << (LDBL_MANL_SIZE - 1);
36 for (b = LDBL_MANH_SIZE; !(u.bits.manl & m); m >>= 1)
39 m = 1lu << (LDBL_MANH_SIZE - 1);
40 for (b = 0; !(u.bits.manh & m); m >>= 1)
43 #ifdef LDBL_IMPLICIT_NBIT
46 return (LDBL_MIN_EXP - b - 1);
47 } else if (u.bits.exp < (LDBL_MAX_EXP << 1) - 1)
48 return (u.bits.exp - LDBL_MAX_EXP + 1);
49 else if (u.bits.manl != 0 || u.bits.manh != 0)