diff options
Diffstat (limited to 'vendor/gmp-6.3.0/mpz/tdiv_qr.c')
-rw-r--r-- | vendor/gmp-6.3.0/mpz/tdiv_qr.c | 111 |
1 files changed, 111 insertions, 0 deletions
diff --git a/vendor/gmp-6.3.0/mpz/tdiv_qr.c b/vendor/gmp-6.3.0/mpz/tdiv_qr.c new file mode 100644 index 0000000..ad82945 --- /dev/null +++ b/vendor/gmp-6.3.0/mpz/tdiv_qr.c @@ -0,0 +1,111 @@ +/* mpz_tdiv_qr(quot,rem,dividend,divisor) -- Set QUOT to DIVIDEND/DIVISOR, + and REM to DIVIDEND mod DIVISOR. + +Copyright 1991, 1993, 1994, 2000, 2001, 2005, 2011, 2012, 2021 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 either: + + * the GNU Lesser General Public License as published by the Free + Software Foundation; either version 3 of the License, or (at your + option) any later version. + +or + + * the GNU General Public License as published by the Free Software + Foundation; either version 2 of the License, or (at your option) any + later version. + +or both in parallel, as here. + +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 General Public License +for more details. + +You should have received copies of the GNU General Public License and the +GNU Lesser General Public License along with the GNU MP Library. If not, +see https://www.gnu.org/licenses/. */ + +#include "gmp-impl.h" +#include "longlong.h" + +void +mpz_tdiv_qr (mpz_ptr quot, mpz_ptr rem, mpz_srcptr num, mpz_srcptr den) +{ + mp_size_t ql, n0; + mp_size_t ns, ds, nl, dl; + mp_ptr np, dp, qp, rp; + TMP_DECL; + + ns = SIZ (num); + ds = SIZ (den); + nl = ABS (ns); + dl = ABS (ds); + ql = nl - dl + 1; + + if (UNLIKELY (dl == 0)) + DIVIDE_BY_ZERO; + + rp = MPZ_REALLOC (rem, dl); + + if (ql <= 0) + { + if (num != rem) + { + np = PTR (num); + MPN_COPY (rp, np, nl); + SIZ (rem) = SIZ (num); + } + /* This needs to follow the assignment to rem, in case the + numerator and quotient are the same. */ + SIZ (quot) = 0; + return; + } + + qp = MPZ_REALLOC (quot, ql); + + TMP_MARK; + np = PTR (num); + dp = PTR (den); + + /* FIXME: We should think about how to handle the temporary allocation. + Perhaps mpn_tdiv_qr should handle it, since it anyway often needs to + allocate temp space. */ + + /* Copy denominator to temporary space if it overlaps with the quotient + or remainder. */ + if (dp == rp || dp == qp) + { + mp_ptr tp; + tp = TMP_ALLOC_LIMBS (dl); + MPN_COPY (tp, dp, dl); + dp = tp; + } + /* Copy numerator to temporary space if it overlaps with the quotient or + remainder. */ + if (np == rp || np == qp) + { + mp_ptr tp; + tp = TMP_ALLOC_LIMBS (nl); + MPN_COPY (tp, np, nl); + np = tp; + } + + for (n0 = 0; *dp == 0; ++dp) + { + rp [n0++] = *np++; + --nl; + } + mpn_tdiv_qr (qp, rp + n0, 0L, np, nl, dp, dl - n0); + + ql -= qp[ql - 1] == 0; + MPN_NORMALIZE (rp, dl); + + SIZ (quot) = (ns ^ ds) >= 0 ? ql : -ql; + SIZ (rem) = ns >= 0 ? dl : -dl; + TMP_FREE; +} |