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1 files changed, 97 insertions, 0 deletions
diff --git a/rts/gmp/mpn/cray/sub_n.c b/rts/gmp/mpn/cray/sub_n.c
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+/* 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;
+}