--- /dev/null
+/* mpfr_set_ui_2exp -- set a MPFR number from a machine unsigned integer with
+ a shift
+
+Copyright 2004, 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
+Contributed by the Arenaire and Cacao 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 2.1 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.LIB. If not, write to
+the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
+MA 02110-1301, USA. */
+
+#define MPFR_NEED_LONGLONG_H
+#include "mpfr-impl.h"
+
+int
+mpfr_set_ui_2exp (mpfr_ptr x, unsigned long i, mp_exp_t e, mp_rnd_t rnd_mode)
+{
+ MPFR_SET_POS (x);
+
+ if (i == 0)
+ {
+ MPFR_SET_ZERO (x);
+ MPFR_RET (0);
+ }
+ else
+ {
+ mp_size_t xn;
+ unsigned int cnt, nbits;
+ mp_limb_t *xp;
+ int inex = 0;
+
+ /* FIXME: support int limbs (e.g. 16-bit limbs on 16-bit proc) */
+ MPFR_ASSERTD (i == (mp_limb_t) i);
+
+ /* Position of the highest limb */
+ xn = (MPFR_PREC (x) - 1) / BITS_PER_MP_LIMB;
+ count_leading_zeros (cnt, (mp_limb_t) i);
+ MPFR_ASSERTD (cnt < BITS_PER_MP_LIMB); /* OK since i != 0 */
+
+ xp = MPFR_MANT(x);
+ xp[xn] = ((mp_limb_t) i) << cnt;
+ /* Zero the xn lower limbs. */
+ MPN_ZERO(xp, xn);
+
+ nbits = BITS_PER_MP_LIMB - cnt;
+ e += nbits; /* exponent _before_ the rounding */
+
+ /* round if MPFR_PREC(x) smaller than length of i */
+ if (MPFR_UNLIKELY (MPFR_PREC (x) < nbits) &&
+ MPFR_UNLIKELY (mpfr_round_raw (xp + xn, xp + xn, nbits, 0,
+ MPFR_PREC (x), rnd_mode, &inex)))
+ {
+ e++;
+ xp[xn] = MPFR_LIMB_HIGHBIT;
+ }
+
+ MPFR_CLEAR_FLAGS (x);
+ MPFR_EXP (x) = e;
+ return mpfr_check_range (x, inex, rnd_mode);
+ }
+}