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Diffstat (limited to 'contrib/libgmp/mpz/sqrt.c')
-rw-r--r--contrib/libgmp/mpz/sqrt.c85
1 files changed, 85 insertions, 0 deletions
diff --git a/contrib/libgmp/mpz/sqrt.c b/contrib/libgmp/mpz/sqrt.c
new file mode 100644
index 000000000000..44c554eb5c9d
--- /dev/null
+++ b/contrib/libgmp/mpz/sqrt.c
@@ -0,0 +1,85 @@
+/* mpz_sqrt(root, u) -- Set ROOT to floor(sqrt(U)).
+
+Copyright (C) 1991, 1993, 1994, 1996 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"
+
+void
+#if __STDC__
+mpz_sqrt (mpz_ptr root, mpz_srcptr op)
+#else
+mpz_sqrt (root, op)
+ mpz_ptr root;
+ mpz_srcptr op;
+#endif
+{
+ mp_size_t op_size, root_size;
+ mp_ptr root_ptr, op_ptr;
+ mp_ptr free_me = NULL;
+ mp_size_t free_me_size;
+ TMP_DECL (marker);
+
+ TMP_MARK (marker);
+ op_size = op->_mp_size;
+ if (op_size < 0)
+ op_size = 1 / (op_size > 0); /* Divide by zero for negative OP. */
+
+ /* The size of the root is accurate after this simple calculation. */
+ root_size = (op_size + 1) / 2;
+
+ root_ptr = root->_mp_d;
+ op_ptr = op->_mp_d;
+
+ if (root->_mp_alloc < root_size)
+ {
+ if (root_ptr == op_ptr)
+ {
+ free_me = root_ptr;
+ free_me_size = root->_mp_alloc;
+ }
+ else
+ (*_mp_free_func) (root_ptr, root->_mp_alloc * BYTES_PER_MP_LIMB);
+
+ root->_mp_alloc = root_size;
+ root_ptr = (mp_ptr) (*_mp_allocate_func) (root_size * BYTES_PER_MP_LIMB);
+ root->_mp_d = root_ptr;
+ }
+ else
+ {
+ /* Make OP not overlap with ROOT. */
+ if (root_ptr == op_ptr)
+ {
+ /* ROOT and OP are identical. Allocate temporary space for OP. */
+ op_ptr = (mp_ptr) TMP_ALLOC (op_size * BYTES_PER_MP_LIMB);
+ /* Copy to the temporary space. Hack: Avoid temporary variable
+ by using ROOT_PTR. */
+ MPN_COPY (op_ptr, root_ptr, op_size);
+ }
+ }
+
+ mpn_sqrtrem (root_ptr, NULL, op_ptr, op_size);
+
+ root->_mp_size = root_size;
+
+ if (free_me != NULL)
+ (*_mp_free_func) (free_me, free_me_size * BYTES_PER_MP_LIMB);
+ TMP_FREE (marker);
+}