Imported gcc-4.4.3

[msp430-gcc.git] / gmp / mpf / ceilfloor.c

diff --git a/gmp/mpf/ceilfloor.c b/gmp/mpf/ceilfloor.c
new file mode 100644 (file)
index 0000000..a0c5d77
--- /dev/null
+++ b/gmp/mpf/ceilfloor.c
@@ -0,0 +1,115 @@
+/* mpf_ceil, mpf_floor -- round an mpf to an integer.
+
+Copyright 2001, 2004 Free Software Foundation, Inc.
+
+This file is part of the GNU MP Library.
+
+The GNU MP 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 MP 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 MP Library.  If not, see http://www.gnu.org/licenses/.  */
+
+#include "gmp.h"
+#include "gmp-impl.h"
+
+
+/* dir==1 for ceil, dir==-1 for floor
+
+   Notice the use of prec+1 ensures mpf_ceil and mpf_floor are equivalent to
+   mpf_set if u is already an integer.  */
+
+static void __gmpf_ceil_or_floor __GMP_PROTO ((REGPARM_2_1 (mpf_ptr, mpf_srcptr, int))) REGPARM_ATTR (1);
+#define mpf_ceil_or_floor(r,u,dir)  __gmpf_ceil_or_floor (REGPARM_2_1 (r, u, dir))
+
+REGPARM_ATTR (1) static void
+mpf_ceil_or_floor (mpf_ptr r, mpf_srcptr u, int dir)
+{
+  mp_ptr     rp, up, p;
+  mp_size_t  size, asize, prec;
+  mp_exp_t   exp;
+
+  size = SIZ(u);
+  if (size == 0)
+    {
+    zero:
+      SIZ(r) = 0;
+      EXP(r) = 0;
+      return;
+    }
+
+  rp = PTR(r);
+  exp = EXP(u);
+  if (exp <= 0)
+    {
+      /* u is only a fraction */
+      if ((size ^ dir) < 0)
+        goto zero;
+      rp[0] = 1;
+      EXP(r) = 1;
+      SIZ(r) = dir;
+      return;
+    }
+  EXP(r) = exp;
+
+  up = PTR(u);
+  asize = ABS (size);
+  up += asize;
+
+  /* skip fraction part of u */
+  asize = MIN (asize, exp);
+
+  /* don't lose precision in the copy */
+  prec = PREC (r) + 1;
+
+  /* skip excess over target precision */
+  asize = MIN (asize, prec);
+
+  up -= asize;
+
+  if ((size ^ dir) >= 0)
+    {
+      /* rounding direction matches sign, must increment if ignored part is
+         non-zero */
+      for (p = PTR(u); p != up; p++)
+        {
+          if (*p != 0)
+            {
+              if (mpn_add_1 (rp, up, asize, CNST_LIMB(1)))
+                {
+                  /* was all 0xFF..FFs, which have become zeros, giving just
+                     a carry */
+                  rp[0] = 1;
+                  asize = 1;
+                  EXP(r)++;
+                }
+              SIZ(r) = (size >= 0 ? asize : -asize);
+              return;
+            }
+        }
+    }
+
+  SIZ(r) = (size >= 0 ? asize : -asize);
+  if (rp != up)
+    MPN_COPY_INCR (rp, up, asize);
+}
+
+
+void
+mpf_ceil (mpf_ptr r, mpf_srcptr u)
+{
+  mpf_ceil_or_floor (r, u, 1);
+}
+
+void
+mpf_floor (mpf_ptr r, mpf_srcptr u)
+{
+  mpf_ceil_or_floor (r, u, -1);
+}