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+/* mpfr_set -- copy of a floating-point number
+
+Copyright 1999, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
+Contributed by the Arenaire and Caramel projects, INRIA.
+
+This file is part of the GNU MPFR Library.
+
+The GNU MPFR 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 3 of the License, or (at your
+option) any later version.
+
+The GNU MPFR 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 MPFR Library; see the file COPYING.LESSER. If not, see
+http://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
+51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */
+
+#include "mpfr-impl.h"
+
+/* set a to abs(b) * signb: a=b when signb = SIGN(b), a=abs(b) when signb=1 */
+int
+mpfr_set4 (mpfr_ptr a, mpfr_srcptr b, mpfr_rnd_t rnd_mode, int signb)
+{
+ /* Sign is ALWAYS copied */
+ MPFR_SET_SIGN (a, signb);
+
+ /* Exponent is also always copied since if the number is singular,
+ the exponent field determined the number.
+ Can't use MPFR_SET_EXP since the exponent may be singular */
+ MPFR_EXP (a) = MPFR_EXP (b);
+
+ if (MPFR_UNLIKELY (MPFR_IS_SINGULAR (b)))
+ {
+ /* MPFR_SET_NAN, MPFR_SET_ZERO and MPFR_SET_INF are useless
+ since MPFR_EXP (a) = MPFR_EXP (b) does the job */
+ if (MPFR_IS_NAN (b))
+ MPFR_RET_NAN;
+ else
+ MPFR_RET (0);
+ }
+ else if (MPFR_LIKELY (MPFR_PREC (b) == MPFR_PREC (a)))
+ {
+ /* Same precision and b is not singular:
+ * just copy the mantissa, and set the exponent and the sign
+ * The result is exact. */
+ MPN_COPY (MPFR_MANT (a), MPFR_MANT (b),
+ (MPFR_PREC (b) + GMP_NUMB_BITS-1)/GMP_NUMB_BITS);
+ MPFR_RET (0);
+ }
+ else
+ {
+ int inex;
+
+ /* Else Round B inside a */
+ MPFR_RNDRAW (inex, a, MPFR_MANT (b), MPFR_PREC (b), rnd_mode, signb,
+ if (MPFR_UNLIKELY ( ++MPFR_EXP (a) > __gmpfr_emax))
+ return mpfr_overflow (a, rnd_mode, signb) );
+ MPFR_RET (inex);
+ }
+}
+
+/* Set a to b */
+#undef mpfr_set
+int
+mpfr_set (mpfr_ptr a, mpfr_srcptr b, mpfr_rnd_t rnd_mode)
+{
+ return mpfr_set4 (a, b, rnd_mode, MPFR_SIGN (b));
+}
+
+/* Set a to |b| */
+#undef mpfr_abs
+int
+mpfr_abs (mpfr_ptr a, mpfr_srcptr b, mpfr_rnd_t rnd_mode)
+{
+ return mpfr_set4 (a, b, rnd_mode, MPFR_SIGN_POS);
+}