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authorKarl Berry <karl@freefriends.org>2021-02-25 19:22:25 +0000
committerKarl Berry <karl@freefriends.org>2021-02-25 19:22:25 +0000
commitad547a6b5986815fda458221149728d9d9ab1d87 (patch)
tree16296910eb3eca724371474ea9aea3994dc69614 /Build/source/libs/mpfr/mpfr-src/src/ui_sub.c
parent947b43de3dd21d58ccc2ffadefc4441ea1c2a813 (diff)
restore Build,TODO from r57911
git-svn-id: svn://tug.org/texlive/trunk@57915 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.c96
1 files changed, 96 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
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index 00000000000..c0b8fadb664
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+++ b/Build/source/libs/mpfr/mpfr-src/src/ui_sub.c
@@ -0,0 +1,96 @@
+/* mpfr_ui_sub -- subtract a floating-point number from an integer
+
+Copyright 2000-2020 Free Software Foundation, Inc.
+Contributed by the AriC and Caramba 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
+https://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));
+
+ /* (unsigned long) 0 is assumed to be a real 0 (unsigned) */
+ 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;
+ }
+ 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 */
+ }
+ MPFR_ASSERTD (MPFR_IS_ZERO (x) && u != 0);
+ /* Note: the fact that u != 0 is important due to signed zeros. */
+ /* u - 0 = u */
+ return mpfr_set_ui (y, u, rnd_mode);
+ }
+
+ /* Main code */
+ {
+ int inex;
+ MPFR_SAVE_EXPO_DECL (expo);
+
+ /* 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);
+
+#ifdef MPFR_LONG_WITHIN_LIMB
+ {
+ mpfr_t uu;
+ mp_limb_t up[1];
+ int cnt;
+
+ MPFR_TMP_INIT1 (up, uu, GMP_NUMB_BITS);
+ /* So, u fits in a mp_limb_t, which justifies the casts below. */
+ MPFR_ASSERTD (u != 0);
+ count_leading_zeros (cnt, (mp_limb_t) u);
+ up[0] = (mp_limb_t) u << cnt;
+ MPFR_SET_EXP (uu, GMP_NUMB_BITS - cnt);
+ inex = mpfr_sub (y, uu, x, rnd_mode);
+ }
+#else
+ {
+ mpfr_t uu;
+
+ mpfr_init2 (uu, sizeof (unsigned long) * CHAR_BIT);
+ mpfr_set_ui (uu, u, MPFR_RNDZ);
+ inex = mpfr_sub (y, uu, x, rnd_mode);
+ mpfr_clear (uu);
+ }
+#endif
+
+ MPFR_SAVE_EXPO_UPDATE_FLAGS (expo, __gmpfr_flags);
+ MPFR_SAVE_EXPO_FREE (expo);
+ return mpfr_check_range (y, inex, rnd_mode);
+ }
+}