Imported gcc-4.4.3

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

diff --git a/gmp/mpf/ui_div.c b/gmp/mpf/ui_div.c
new file mode 100644 (file)
index 0000000..39a0bd9
--- /dev/null
+++ b/gmp/mpf/ui_div.c
@@ -0,0 +1,117 @@
+/* mpf_ui_div -- Divide an unsigned integer with a float.
+
+Copyright 1993, 1994, 1995, 1996, 2000, 2001, 2002, 2004, 2005 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 <stdio.h>  /* for NULL */
+#include "gmp.h"
+#include "gmp-impl.h"
+#include "longlong.h"
+
+
+void
+mpf_ui_div (mpf_ptr r, unsigned long int u, mpf_srcptr v)
+{
+  mp_srcptr vp;
+  mp_ptr rp, tp, remp, new_vp;
+  mp_size_t vsize;
+  mp_size_t rsize, prospective_rsize, zeros, tsize, high_zero;
+  mp_size_t sign_quotient;
+  mp_size_t prec;
+  mp_exp_t rexp;
+  TMP_DECL;
+
+  vsize = v->_mp_size;
+  sign_quotient = vsize;
+  vsize = ABS (vsize);
+  prec = r->_mp_prec;
+
+  if (UNLIKELY (vsize == 0))
+    DIVIDE_BY_ZERO;
+
+  if (UNLIKELY (u == 0))
+    {
+      r->_mp_size = 0;
+      r->_mp_exp = 0;
+      return;
+    }
+
+  TMP_MARK;
+  rexp = 1 - v->_mp_exp + 1;
+
+  rp = r->_mp_d;
+  vp = v->_mp_d;
+
+  prospective_rsize = 1 - vsize + 1;    /* quot from using given u,v sizes */
+  rsize = prec + 1;                     /* desired quot size */
+
+  zeros = rsize - prospective_rsize;    /* padding u to give rsize */
+  tsize = 1 + zeros;                    /* u with zeros */
+
+  if (WANT_TMP_DEBUG)
+    {
+      /* separate alloc blocks, for malloc debugging */
+      remp = TMP_ALLOC_LIMBS (vsize);
+      tp = TMP_ALLOC_LIMBS (tsize);
+      new_vp = NULL;
+      if (rp == vp)
+        new_vp = TMP_ALLOC_LIMBS (vsize);
+    }
+  else
+    {
+      /* one alloc with calculated size, for efficiency */
+      mp_size_t size = vsize + tsize + (rp == vp ? vsize : 0);
+      remp = TMP_ALLOC_LIMBS (size);
+      tp = remp + vsize;
+      new_vp = tp + tsize;
+    }
+
+  /* ensure divisor doesn't overlap quotient */
+  if (rp == vp)
+    {
+      MPN_COPY (new_vp, vp, vsize);
+      vp = new_vp;
+    }
+
+  MPN_ZERO (tp, tsize-1);
+
+  tp[tsize - 1] = u & GMP_NUMB_MASK;
+#if BITS_PER_ULONG > GMP_NUMB_BITS
+  if (u > GMP_NUMB_MAX)
+    {
+      /* tsize-vsize+1 == rsize, so tsize >= rsize.  rsize == prec+1 >= 2,
+         so tsize >= 2, hence there's room for 2-limb u with nails */
+      ASSERT (tsize >= 2);
+      tp[tsize - 1] = u >> GMP_NUMB_BITS;
+      tp[tsize - 2] = u & GMP_NUMB_MASK;
+      rexp++;
+    }
+#endif
+
+  ASSERT (tsize-vsize+1 == rsize);
+  mpn_tdiv_qr (rp, remp, (mp_size_t) 0, tp, tsize, vp, vsize);
+
+  /* strip possible zero high limb */
+  high_zero = (rp[rsize-1] == 0);
+  rsize -= high_zero;
+  rexp -= high_zero;
+
+  r->_mp_size = sign_quotient >= 0 ? rsize : -rsize;
+  r->_mp_exp = rexp;
+  TMP_FREE;
+}