1 files changed, 50 insertions, 0 deletions
diff --git a/src/d_sub.c b/src/d_sub.c
new file mode 100644
index 0000000..59d810f
--- /dev/null
+++ b/src/d_sub.c
@@ -0,0 +1,50 @@
+/* mpfr_d_sub -- subtract a multiple precision floating-point number
+                 from a machine double precision float
+
+Copyright 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_d_sub (mpfr_ptr a, double b, mpfr_srcptr c, mpfr_rnd_t rnd_mode)
+{
+  int inexact;
+  mpfr_t d;
+  MPFR_SAVE_EXPO_DECL (expo);
+
+  MPFR_LOG_FUNC (
+    ("b=%.20g c[%Pu]=%*.Rg rnd=%d", b, mpfr_get_prec (c), mpfr_log_prec, c, rnd_mode),
+    ("a[%Pu]=%*.Rg", mpfr_get_prec (a), mpfr_log_prec, a));
+
+  MPFR_SAVE_EXPO_MARK (expo);
+
+  mpfr_init2 (d, IEEE_DBL_MANT_DIG);
+  inexact = mpfr_set_d (d, b, rnd_mode);
+  MPFR_ASSERTN (inexact == 0);
+
+  mpfr_clear_flags ();
+  inexact = mpfr_sub (a, d, c, rnd_mode);
+  MPFR_SAVE_EXPO_UPDATE_FLAGS (expo, __gmpfr_flags);
+
+  mpfr_clear(d);
+  MPFR_SAVE_EXPO_FREE (expo);
+  return mpfr_check_range (a, inexact, rnd_mode);
+}