X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=rts%2Fgmp%2Fmpn%2Fgeneric%2Fsqr_basecase.c;fp=rts%2Fgmp%2Fmpn%2Fgeneric%2Fsqr_basecase.c;h=760258a3e0de23f721ef5f3887f5918f0fc9db34;hb=0065d5ab628975892cea1ec7303f968c3338cbe1;hp=0000000000000000000000000000000000000000;hpb=28a464a75e14cece5db40f2765a29348273ff2d2;p=ghc-hetmet.git diff --git a/rts/gmp/mpn/generic/sqr_basecase.c b/rts/gmp/mpn/generic/sqr_basecase.c new file mode 100644 index 0000000..760258a --- /dev/null +++ b/rts/gmp/mpn/generic/sqr_basecase.c @@ -0,0 +1,83 @@ +/* mpn_sqr_basecase -- Internal routine to square two natural numbers + of length m and n. + + THIS IS AN INTERNAL FUNCTION WITH A MUTABLE INTERFACE. IT IS ONLY + SAFE TO REACH THIS FUNCTION THROUGH DOCUMENTED INTERFACES. + + +Copyright (C) 1991, 1992, 1993, 1994, 1996, 1997, 2000 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 Lesser General Public License as published by +the Free Software Foundation; either version 2.1 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 Lesser General Public +License for more details. + +You should have received a copy of the GNU Lesser 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" + +void +#if __STDC__ +mpn_sqr_basecase (mp_ptr prodp, mp_srcptr up, mp_size_t n) +#else +mpn_sqr_basecase (prodp, up, n) + mp_ptr prodp; + mp_srcptr up; + mp_size_t n; +#endif +{ + mp_size_t i; + + { + /* N.B.! We need the superfluous indirection through argh to work around + a reloader bug in GCC 2.7.*. */ + mp_limb_t x; + mp_limb_t argh; + x = up[0]; + umul_ppmm (argh, prodp[0], x, x); + prodp[1] = argh; + } + if (n > 1) + { + mp_limb_t tarr[2 * KARATSUBA_SQR_THRESHOLD]; + mp_ptr tp = tarr; + mp_limb_t cy; + + /* must fit 2*n limbs in tarr */ + ASSERT (n <= KARATSUBA_SQR_THRESHOLD); + + cy = mpn_mul_1 (tp, up + 1, n - 1, up[0]); + tp[n - 1] = cy; + for (i = 2; i < n; i++) + { + mp_limb_t cy; + cy = mpn_addmul_1 (tp + 2 * i - 2, up + i, n - i, up[i - 1]); + tp[n + i - 2] = cy; + } + for (i = 1; i < n; i++) + { + mp_limb_t x; + x = up[i]; + umul_ppmm (prodp[2 * i + 1], prodp[2 * i], x, x); + } + { + mp_limb_t cy; + cy = mpn_lshift (tp, tp, 2 * n - 2, 1); + cy += mpn_add_n (prodp + 1, prodp + 1, tp, 2 * n - 2); + prodp[2 * n - 1] += cy; + } + } +}