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Diffstat (limited to 'rts/gmp/mpz/get_si.c')
-rw-r--r--rts/gmp/mpz/get_si.c43
1 files changed, 43 insertions, 0 deletions
diff --git a/rts/gmp/mpz/get_si.c b/rts/gmp/mpz/get_si.c
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index 0000000000..8a5d0e4803
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+++ b/rts/gmp/mpz/get_si.c
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+/* mpz_get_si(integer) -- Return the least significant digit from INTEGER.
+
+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 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"
+
+signed long int
+#if __STDC__
+mpz_get_si (mpz_srcptr op)
+#else
+mpz_get_si (op)
+ mpz_srcptr op;
+#endif
+{
+ mp_size_t size = op->_mp_size;
+ mp_limb_t low_limb = op->_mp_d[0];
+
+ if (size > 0)
+ return low_limb % ((mp_limb_t) 1 << (BITS_PER_MP_LIMB - 1));
+ else if (size < 0)
+ /* This convoluted expression is necessary to properly handle 0x80000000 */
+ return ~((low_limb - 1) % ((mp_limb_t) 1 << (BITS_PER_MP_LIMB - 1)));
+ else
+ return 0;
+}