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diff --git a/rts/gmp/mpn/cray/sub_n.c b/rts/gmp/mpn/cray/sub_n.c
new file mode 100644
index 0000000..902e07a
--- /dev/null
+++ b/rts/gmp/mpn/cray/sub_n.c
@@ -0,0 +1,97 @@
+/* mpn_sub_n -- Subtract two limb vectors of equal, non-zero length.
+   For Cray vector processors.
+
+   Copyright (C) 1996, 2000 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 2.1 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; see the file COPYING.LIB.  If not, write to
+   the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+   MA 02111-1307, USA.  */
+
+#include "gmp.h"
+#include "gmp-impl.h"
+
+mp_limb_t
+mpn_sub_n (c, a, b, n)
+     mp_ptr c;
+     mp_srcptr a, b;
+     mp_size_t n;
+{
+  mp_size_t i;
+  mp_size_t nm1 = n - 1;
+  int more_carries = 0;
+  int carry_out;
+
+  /* For small operands the non-vector code is faster.  */
+  if (n < 16)
+    goto sequential;
+
+  if (a == c || b == c)
+    {
+      TMP_DECL (marker);
+      TMP_MARK (marker);
+      if (c == a)
+	{
+	  /* allocate temp space for a */
+	  mp_ptr ax = (mp_ptr) TMP_ALLOC (n * BYTES_PER_MP_LIMB);
+	  MPN_COPY (ax, a, n);
+	  a = (mp_srcptr) ax;
+	}
+      if (c == b)
+	{
+	  /* allocate temp space for b */
+	  mp_ptr bx = (mp_ptr) TMP_ALLOC (n * BYTES_PER_MP_LIMB);
+	  MPN_COPY (bx, b, n);
+	  b = (mp_srcptr) bx;
+	}
+      carry_out = mpn_sub_n (c, a, b, n);
+      TMP_FREE (marker);
+      return carry_out;
+    }
+
+  carry_out = a[nm1] < b[nm1];
+
+#pragma _CRI ivdep			/* Cray PVP systems */
+  for (i = nm1; i > 0; i--)
+    {
+      int cy_in; mp_limb_t t;
+      cy_in = a[i - 1] < b[i - 1];
+      t = a[i] - b[i];
+      more_carries += t < cy_in;
+      c[i] = t - cy_in;
+    }
+  c[0] = a[0] - b[0];
+
+  if (more_carries)
+    {
+      /* This won't vectorize, but we should come here rarely.  */
+      int cy;
+    sequential:
+      cy = 0;
+      for (i = 0; i < n; i++)
+	{
+	  mp_limb_t ai, ci, t;
+	  ai = a[i];
+	  t = b[i] + cy;
+	  cy = t < cy;
+	  ci = ai - t;
+	  cy += ci > ai;
+	  c[i] = ci;
+	}
+      carry_out = cy;
+    }
+
+  return carry_out;
+}