1/* mpfr_d_sub -- subtract a multiple precision floating-point number 2 from a machine double precision float 3 4Copyright 2007-2023 Free Software Foundation, Inc. 5Contributed by the AriC and Caramba projects, INRIA. 6 7This file is part of the GNU MPFR Library. 8 9The GNU MPFR Library is free software; you can redistribute it and/or modify 10it under the terms of the GNU Lesser General Public License as published by 11the Free Software Foundation; either version 3 of the License, or (at your 12option) any later version. 13 14The GNU MPFR Library is distributed in the hope that it will be useful, but 15WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 16or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 17License for more details. 18 19You should have received a copy of the GNU Lesser General Public License 20along with the GNU MPFR Library; see the file COPYING.LESSER. If not, see 21https://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc., 2251 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */ 23 24#include "mpfr-impl.h" 25 26int 27mpfr_d_sub (mpfr_ptr a, double b, mpfr_srcptr c, mpfr_rnd_t rnd_mode) 28{ 29 int inexact; 30 mpfr_t d; 31 mp_limb_t tmp_man[MPFR_LIMBS_PER_DOUBLE]; 32 MPFR_SAVE_EXPO_DECL (expo); 33 34 MPFR_LOG_FUNC ( 35 ("b=%.20g c[%Pu]=%.*Rg rnd=%d", b, mpfr_get_prec (c), mpfr_log_prec, c, rnd_mode), 36 ("a[%Pu]=%.*Rg", mpfr_get_prec (a), mpfr_log_prec, a)); 37 38 MPFR_SAVE_EXPO_MARK (expo); 39 40 MPFR_TMP_INIT1(tmp_man, d, IEEE_DBL_MANT_DIG); 41 inexact = mpfr_set_d (d, b, rnd_mode); 42 MPFR_ASSERTD (inexact == 0); 43 44 MPFR_CLEAR_FLAGS (); 45 inexact = mpfr_sub (a, d, c, rnd_mode); 46 MPFR_SAVE_EXPO_UPDATE_FLAGS (expo, __gmpfr_flags); 47 48 MPFR_SAVE_EXPO_FREE (expo); 49 return mpfr_check_range (a, inexact, rnd_mode); 50} 51