diff options
Diffstat (limited to 'contrib/libgmp/mpz/tdiv_qr_ui.c')
-rw-r--r-- | contrib/libgmp/mpz/tdiv_qr_ui.c | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/contrib/libgmp/mpz/tdiv_qr_ui.c b/contrib/libgmp/mpz/tdiv_qr_ui.c new file mode 100644 index 0000000..cb5041c --- /dev/null +++ b/contrib/libgmp/mpz/tdiv_qr_ui.c @@ -0,0 +1,78 @@ +/* mpz_tdiv_qr_ui(quot,rem,dividend,short_divisor) -- + Set QUOT to DIVIDEND / SHORT_DIVISOR + and REM to DIVIDEND mod SHORT_DIVISOR. + +Copyright (C) 1991, 1993, 1994, 1996 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" + +void +#if __STDC__ +mpz_tdiv_qr_ui (mpz_ptr quot, mpz_ptr rem, mpz_srcptr dividend, unsigned long int divisor) +#else +mpz_tdiv_qr_ui (quot, rem, dividend, divisor) + mpz_ptr quot; + mpz_ptr rem; + mpz_srcptr dividend; + unsigned long int divisor; +#endif +{ + mp_size_t dividend_size; + mp_size_t size; + mp_ptr quot_ptr; + mp_limb_t remainder_limb; + + dividend_size = dividend->_mp_size; + size = ABS (dividend_size); + + if (size == 0) + { + quot->_mp_size = 0; + rem->_mp_size = 0; + return; + } + + /* No need for temporary allocation and copying if QUOT == DIVIDEND as + the divisor is just one limb, and thus no intermediate remainders + need to be stored. */ + + if (quot->_mp_alloc < size) + _mpz_realloc (quot, size); + + quot_ptr = quot->_mp_d; + + remainder_limb = mpn_divmod_1 (quot_ptr, dividend->_mp_d, size, + (mp_limb_t) divisor); + + if (remainder_limb == 0) + rem->_mp_size = 0; + else + { + /* Store the single-limb remainder. We don't check if there's space + for just one limb, since no function ever makes zero space. */ + rem->_mp_size = dividend_size >= 0 ? 1 : -1; + rem->_mp_d[0] = remainder_limb; + } + + /* The quotient is SIZE limbs, but the most significant might be zero. */ + size -= quot_ptr[size - 1] == 0; + quot->_mp_size = dividend_size >= 0 ? size : -size; +} |