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-rw-r--r--gnu/lib/libgmp/mpz_div_2exp.c53
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diff --git a/gnu/lib/libgmp/mpz_div_2exp.c b/gnu/lib/libgmp/mpz_div_2exp.c
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+/* mpz_div_2exp -- Divide a bignum by 2**CNT
+
+Copyright (C) 1991 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 General Public License as published by
+the Free Software Foundation; either version 2, 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 General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with the GNU MP Library; see the file COPYING. If not, write to
+the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
+
+#include "gmp.h"
+#include "gmp-impl.h"
+
+void
+#ifdef __STDC__
+mpz_div_2exp (MP_INT *w, const MP_INT *u, unsigned long int cnt)
+#else
+mpz_div_2exp (w, u, cnt)
+ MP_INT *w;
+ const MP_INT *u;
+ unsigned long int cnt;
+#endif
+{
+ mp_size usize = u->size;
+ mp_size wsize;
+ mp_size abs_usize = ABS (usize);
+ mp_size limb_cnt;
+
+ limb_cnt = cnt / BITS_PER_MP_LIMB;
+ wsize = abs_usize - limb_cnt;
+ if (wsize <= 0)
+ wsize = 0;
+ else
+ {
+ if (w->alloc < wsize)
+ _mpz_realloc (w, wsize);
+
+ wsize = mpn_rshift (w->d, u->d + limb_cnt, abs_usize - limb_cnt,
+ cnt % BITS_PER_MP_LIMB);
+ }
+
+ w->size = (usize >= 0) ? wsize : -wsize;
+}
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