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Diffstat (limited to 'Build/source/libs/mpfr/mpfr-3.1.2/src/sub.c')
-rw-r--r--Build/source/libs/mpfr/mpfr-3.1.2/src/sub.c116
1 files changed, 116 insertions, 0 deletions
diff --git a/Build/source/libs/mpfr/mpfr-3.1.2/src/sub.c b/Build/source/libs/mpfr/mpfr-3.1.2/src/sub.c
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index 00000000000..d1af16f7191
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+++ b/Build/source/libs/mpfr/mpfr-3.1.2/src/sub.c
@@ -0,0 +1,116 @@
+/* mpfr_sub -- subtract two floating-point numbers
+
+Copyright 2001, 2002, 2003, 2004, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 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. */
+
+#include "mpfr-impl.h"
+
+int
+mpfr_sub (mpfr_ptr a, mpfr_srcptr b, mpfr_srcptr c, mpfr_rnd_t rnd_mode)
+{
+ MPFR_LOG_FUNC
+ (("b[%Pu]=%.*Rg c[%Pu]=%.*Rg rnd=%d",
+ mpfr_get_prec (b), mpfr_log_prec, b,
+ mpfr_get_prec (c), mpfr_log_prec, c, rnd_mode),
+ ("a[%Pu]=%.*Rg", mpfr_get_prec (a), mpfr_log_prec, a));
+
+ if (MPFR_ARE_SINGULAR (b,c))
+ {
+ if (MPFR_IS_NAN (b) || MPFR_IS_NAN (c))
+ {
+ MPFR_SET_NAN (a);
+ MPFR_RET_NAN;
+ }
+ else if (MPFR_IS_INF (b))
+ {
+ if (!MPFR_IS_INF (c) || MPFR_SIGN (b) != MPFR_SIGN(c))
+ {
+ MPFR_SET_INF (a);
+ MPFR_SET_SAME_SIGN (a, b);
+ MPFR_RET (0); /* exact */
+ }
+ else
+ {
+ MPFR_SET_NAN (a); /* Inf - Inf */
+ MPFR_RET_NAN;
+ }
+ }
+ else if (MPFR_IS_INF (c))
+ {
+ MPFR_SET_INF (a);
+ MPFR_SET_OPPOSITE_SIGN (a, c);
+ MPFR_RET (0); /* exact */
+ }
+ else if (MPFR_IS_ZERO (b))
+ {
+ if (MPFR_IS_ZERO (c))
+ {
+ int sign = rnd_mode != MPFR_RNDD
+ ? ((MPFR_IS_NEG(b) && MPFR_IS_POS(c)) ? -1 : 1)
+ : ((MPFR_IS_POS(b) && MPFR_IS_NEG(c)) ? 1 : -1);
+ MPFR_SET_SIGN (a, sign);
+ MPFR_SET_ZERO (a);
+ MPFR_RET(0); /* 0 - 0 is exact */
+ }
+ else
+ return mpfr_neg (a, c, rnd_mode);
+ }
+ else
+ {
+ MPFR_ASSERTD (MPFR_IS_ZERO (c));
+ return mpfr_set (a, b, rnd_mode);
+ }
+ }
+
+ MPFR_ASSERTD (MPFR_IS_PURE_FP (b));
+ MPFR_ASSERTD (MPFR_IS_PURE_FP (c));
+
+ if (MPFR_LIKELY (MPFR_SIGN (b) == MPFR_SIGN (c)))
+ { /* signs are equal, it's a real subtraction */
+ if (MPFR_LIKELY (MPFR_PREC (a) == MPFR_PREC (b)
+ && MPFR_PREC (b) == MPFR_PREC (c)))
+ return mpfr_sub1sp (a, b, c, rnd_mode);
+ else
+ return mpfr_sub1 (a, b, c, rnd_mode);
+ }
+ else
+ { /* signs differ, it's an addition */
+ if (MPFR_GET_EXP (b) < MPFR_GET_EXP (c))
+ { /* exchange rounding modes toward +/- infinity */
+ int inexact;
+ rnd_mode = MPFR_INVERT_RND (rnd_mode);
+ if (MPFR_LIKELY (MPFR_PREC (a) == MPFR_PREC (b)
+ && MPFR_PREC (b) == MPFR_PREC (c)))
+ inexact = mpfr_add1sp (a, c, b, rnd_mode);
+ else
+ inexact = mpfr_add1 (a, c, b, rnd_mode);
+ MPFR_CHANGE_SIGN (a);
+ return -inexact;
+ }
+ else
+ {
+ if (MPFR_LIKELY (MPFR_PREC (a) == MPFR_PREC (b)
+ && MPFR_PREC (b) == MPFR_PREC (c)))
+ return mpfr_add1sp (a, b, c, rnd_mode);
+ else
+ return mpfr_add1 (a, b, c, rnd_mode);
+ }
+ }
+}