1 files changed, 111 insertions, 0 deletions
diff --git a/src/add.c b/src/add.c
new file mode 100644
index 0000000..4b938dc
--- /dev/null
+++ b/src/add.c
@@ -0,0 +1,111 @@
+/* mpfr_add -- add two floating-point numbers
+
+Copyright 1999, 2000, 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_add (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;
+        }
+      /* neither b nor c is NaN here */
+      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);
+              MPFR_RET_NAN;
+            }
+        }
+      else if (MPFR_IS_INF(c))
+          {
+            MPFR_SET_INF(a);
+            MPFR_SET_SAME_SIGN(a, c);
+            MPFR_RET(0); /* exact */
+          }
+      /* now either b or c is zero */
+      else if (MPFR_IS_ZERO(b))
+        {
+          if (MPFR_IS_ZERO(c))
+            {
+              /* for round away, we take the same convention for 0 + 0
+                 as for round to zero or to nearest: it always gives +0,
+                 except (-0) + (-0) = -0. */
+              MPFR_SET_SIGN(a,
+                            (rnd_mode != MPFR_RNDD ?
+                             ((MPFR_IS_NEG(b) && MPFR_IS_NEG(c)) ? -1 : 1) :
+                             ((MPFR_IS_POS(b) && MPFR_IS_POS(c)) ? 1 : -1)));
+              MPFR_SET_ZERO(a);
+              MPFR_RET(0); /* 0 + 0 is exact */
+            }
+          return mpfr_set (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_UNLIKELY(MPFR_SIGN(b) != MPFR_SIGN(c)))
+    { /* signs differ, it is a 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 are equal, it's an addition */
+      if (MPFR_LIKELY(MPFR_PREC(a) == MPFR_PREC(b)
+                      && MPFR_PREC(b) == MPFR_PREC(c)))
+        if (MPFR_GET_EXP(b) < MPFR_GET_EXP(c))
+          return mpfr_add1sp(a, c, b, rnd_mode);
+        else
+          return mpfr_add1sp(a, b, c, rnd_mode);
+      else
+        if (MPFR_GET_EXP(b) < MPFR_GET_EXP(c))
+          return mpfr_add1(a, c, b, rnd_mode);
+        else
+          return mpfr_add1(a, b, c, rnd_mode);
+    }
+}