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author | markm <markm@FreeBSD.org> | 1996-10-20 08:49:26 +0000 |
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committer | markm <markm@FreeBSD.org> | 1996-10-20 08:49:26 +0000 |
commit | 6ec01646dc55b6fa688ed5906e0d52556d174da2 (patch) | |
tree | ecc4c214d76efa8e1b2fb33ac2f0aab18ea03ebf /contrib/libgmp/mpz/sizeinbase.c | |
download | FreeBSD-src-6ec01646dc55b6fa688ed5906e0d52556d174da2.zip FreeBSD-src-6ec01646dc55b6fa688ed5906e0d52556d174da2.tar.gz |
Clean import of libgmp 2.0.2, with only the non-x86 bits removed.
BMakefiles and other bits will follow.
Requested by: Andrey Chernov
Made world by: Chuck Robey
Diffstat (limited to 'contrib/libgmp/mpz/sizeinbase.c')
-rw-r--r-- | contrib/libgmp/mpz/sizeinbase.c | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/contrib/libgmp/mpz/sizeinbase.c b/contrib/libgmp/mpz/sizeinbase.c new file mode 100644 index 0000000..51bd555 --- /dev/null +++ b/contrib/libgmp/mpz/sizeinbase.c @@ -0,0 +1,60 @@ +/* mpz_sizeinbase(x, base) -- return an approximation to the number of + character the integer X would have printed in base BASE. The + approximation is never too small. + +Copyright (C) 1991, 1993, 1994, 1995 Free Software Foundation, Inc. + +This file is part of the GNU MP Library. + +The GNU MP Library is free software; you can redistribute it and/or modify +it under the terms of the GNU Library General Public License as published by +the Free Software Foundation; either version 2 of the License, or (at your +option) any later version. + +The GNU MP Library is distributed in the hope that it will be useful, but +WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY +or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public +License for more details. + +You should have received a copy of the GNU Library General Public License +along with the GNU MP Library; see the file COPYING.LIB. If not, write to +the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, +MA 02111-1307, USA. */ + +#include "gmp.h" +#include "gmp-impl.h" +#include "longlong.h" + +size_t +#if __STDC__ +mpz_sizeinbase (mpz_srcptr x, int base) +#else +mpz_sizeinbase (x, base) + mpz_srcptr x; + int base; +#endif +{ + mp_size_t size = ABS (x->_mp_size); + int lb_base, cnt; + size_t totbits; + + /* Special case for X == 0. */ + if (size == 0) + return 1; + + /* Calculate the total number of significant bits of X. */ + count_leading_zeros (cnt, x->_mp_d[size - 1]); + totbits = size * BITS_PER_MP_LIMB - cnt; + + if ((base & (base - 1)) == 0) + { + /* Special case for powers of 2, giving exact result. */ + + count_leading_zeros (lb_base, base); + lb_base = BITS_PER_MP_LIMB - lb_base - 1; + + return (totbits + lb_base - 1) / lb_base; + } + else + return (size_t) (totbits * __mp_bases[base].chars_per_bit_exactly) + 1; +} |