Imported gcc-4.4.3

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

diff --git a/gmp/mpf/trunc.c b/gmp/mpf/trunc.c
new file mode 100644 (file)
index 0000000..d329bc1
--- /dev/null
+++ b/gmp/mpf/trunc.c
@@ -0,0 +1,64 @@
+/* mpf_trunc -- truncate an mpf to an integer.
+
+Copyright 2001 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"
+
+
+/* Notice the use of prec+1 ensures mpf_trunc is equivalent to mpf_set if u
+   is already an integer.  */
+
+void
+mpf_trunc (mpf_ptr r, mpf_srcptr u)
+{
+  mp_ptr     rp;
+  mp_srcptr  up;
+  mp_size_t  size, asize, prec;
+  mp_exp_t   exp;
+
+  exp = EXP(u);
+  size = SIZ(u);
+  if (size == 0 || exp <= 0)
+    {
+      /* u is only a fraction */
+      SIZ(r) = 0;
+      EXP(r) = 0;
+      return;
+    }
+
+  up = PTR(u);
+  EXP(r) = exp;
+  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;
+  rp = PTR(r);
+  SIZ(r) = (size >= 0 ? asize : -asize);
+  if (rp != up)
+    MPN_COPY_INCR (rp, up, asize);
+}