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author | Akira Kakuto <kakuto@fuk.kindai.ac.jp> | 2016-02-22 06:02:38 +0000 |
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committer | Akira Kakuto <kakuto@fuk.kindai.ac.jp> | 2016-02-22 06:02:38 +0000 |
commit | b2ef5d127f546fa32f303b1dedfc4a6390ad677e (patch) | |
tree | 17cd90adb54888579df0e08223bf4909332380c2 /Build/source/libs/mpfr/mpfr-src/src/ui_sub.c | |
parent | 05d739843a7c50294efbda2abf2ab4ea3fc146b1 (diff) |
libs/mpfr: New convention
git-svn-id: svn://tug.org/texlive/trunk@39814 c570f23f-e606-0410-a88d-b1316a301751
Diffstat (limited to 'Build/source/libs/mpfr/mpfr-src/src/ui_sub.c')
-rw-r--r-- | Build/source/libs/mpfr/mpfr-src/src/ui_sub.c | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/Build/source/libs/mpfr/mpfr-src/src/ui_sub.c b/Build/source/libs/mpfr/mpfr-src/src/ui_sub.c new file mode 100644 index 00000000000..bb8166ef234 --- /dev/null +++ b/Build/source/libs/mpfr/mpfr-src/src/ui_sub.c @@ -0,0 +1,78 @@ +/* mpfr_ui_sub -- subtract a floating-point number from an integer + +Copyright 2000-2015 Free Software Foundation, Inc. +Contributed by the AriC and Caramel projects, INRIA. + +This file is part of the GNU MPFR Library. + +The GNU MPFR 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 3 of the License, or (at your +option) any later version. + +The GNU 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 Lesser General Public +License for more details. + +You should have received a copy of the GNU Lesser General Public License +along with the GNU MPFR Library; see the file COPYING.LESSER. If not, see +http://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc., +51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */ + +#define MPFR_NEED_LONGLONG_H +#include "mpfr-impl.h" + +int +mpfr_ui_sub (mpfr_ptr y, unsigned long int u, mpfr_srcptr x, mpfr_rnd_t rnd_mode) +{ + MPFR_LOG_FUNC + (("u=%lu x[%Pu]=%.*Rg rnd=%d", + u, mpfr_get_prec(x), mpfr_log_prec, x, rnd_mode), + ("y[%Pu]=%.*Rg", mpfr_get_prec(y), mpfr_log_prec, y)); + + if (MPFR_UNLIKELY (u == 0)) + return mpfr_neg (y, x, rnd_mode); + + if (MPFR_UNLIKELY(MPFR_IS_SINGULAR(x))) + { + if (MPFR_IS_NAN(x)) + { + MPFR_SET_NAN(y); + MPFR_RET_NAN; + } + else if (MPFR_IS_INF(x)) + { + /* u - Inf = -Inf and u - -Inf = +Inf */ + MPFR_SET_INF(y); + MPFR_SET_OPPOSITE_SIGN(y,x); + MPFR_RET(0); /* +/-infinity is exact */ + } + else /* x is zero */ + /* u - 0 = u */ + return mpfr_set_ui(y, u, rnd_mode); + } + else + { + mpfr_t uu; + mp_limb_t up[1]; + int cnt; + int inex; + + MPFR_SAVE_EXPO_DECL (expo); + + MPFR_TMP_INIT1 (up, uu, GMP_NUMB_BITS); + MPFR_ASSERTN(u == (mp_limb_t) u); + count_leading_zeros (cnt, (mp_limb_t) u); + up[0] = (mp_limb_t) u << cnt; + + /* Optimization note: Exponent save/restore operations may be + removed if mpfr_sub works even when uu is out-of-range. */ + MPFR_SAVE_EXPO_MARK (expo); + MPFR_SET_EXP (uu, GMP_NUMB_BITS - cnt); + inex = mpfr_sub (y, uu, x, rnd_mode); + MPFR_SAVE_EXPO_UPDATE_FLAGS (expo, __gmpfr_flags); + MPFR_SAVE_EXPO_FREE (expo); + return mpfr_check_range(y, inex, rnd_mode); + } +} |