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diff --git a/contrib/libgmp/mpz/sizeinbase.c b/contrib/libgmp/mpz/sizeinbase.c
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+/* mpz_sizeinbase(x, base) -- return an approximation to the number of
+ character the integer X would have printed in base BASE. The
+ approximation is never too small.
+
+Copyright (C) 1991, 1993, 1994, 1995 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 Library General Public License as published by
+the Free Software Foundation; either version 2 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 Library General Public
+License for more details.
+
+You should have received a copy of the GNU Library 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"
+#include "longlong.h"
+
+size_t
+#if __STDC__
+mpz_sizeinbase (mpz_srcptr x, int base)
+#else
+mpz_sizeinbase (x, base)
+ mpz_srcptr x;
+ int base;
+#endif
+{
+ mp_size_t size = ABS (x->_mp_size);
+ int lb_base, cnt;
+ size_t totbits;
+
+ /* Special case for X == 0. */
+ if (size == 0)
+ return 1;
+
+ /* Calculate the total number of significant bits of X. */
+ count_leading_zeros (cnt, x->_mp_d[size - 1]);
+ totbits = size * BITS_PER_MP_LIMB - cnt;
+
+ if ((base & (base - 1)) == 0)
+ {
+ /* Special case for powers of 2, giving exact result. */
+
+ count_leading_zeros (lb_base, base);
+ lb_base = BITS_PER_MP_LIMB - lb_base - 1;
+
+ return (totbits + lb_base - 1) / lb_base;
+ }
+ else
+ return (size_t) (totbits * __mp_bases[base].chars_per_bit_exactly) + 1;
+}
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