/* mpfr_set_f -- set a MPFR number from a GNU MPF number Copyright (C) 1999-2000 PolKA project, Inria Lorraine and Loria This file is part of the MPFR Library. The MPFR 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 MPFR 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 MPFR 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 #include "gmp.h" #include "gmp-impl.h" #include "longlong.h" #include "mpfr.h" void #if __STDC__ mpfr_set_f(mpfr_ptr y, mpf_srcptr x, char rnd_mode) #else mpfr_set_f(y, x, rnd_mode) mpfr_ptr y; mpf_srcptr x; char rnd_mode; #endif { mp_limb_t *my, *mx, *tmp; unsigned long cnt, sx, sy; TMP_DECL(marker); sx = ABS(SIZ(x)); sy = ABSSIZE(y); my = MANT(y); mx = MANT(x); if (sx==0) { /* x is zero */ SET_ZERO(y); return; } count_leading_zeros(cnt, mx[sx - 1]); if (SIZ(x)*SIGN(y)<0) CHANGE_SIGN(y); if (sy < sx) { unsigned long xprec = sx * BITS_PER_MP_LIMB; tmp = (mp_limb_t*) TMP_ALLOC(xprec); if (cnt) mpn_lshift(tmp, mx, sx, cnt); else MPN_COPY(tmp, mx, sx); mpfr_round_raw(my, tmp, xprec, (SIZ(x)<0), PREC(y), rnd_mode); } else { if (cnt) mpn_lshift(my + sy - sx, mx, sx, cnt); else MPN_COPY(my + sy - sx, mx, sy); MPN_ZERO(my, sy - sx); /* no rounding necessary, since y has a larger mantissa */ } EXP(y) = EXP(x) * BITS_PER_MP_LIMB - cnt; TMP_FREE(marker); }