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Diffstat (limited to 'Build/source/libs/mpfr/mpfr-3.1.2/src/get_ui.c')
-rw-r--r-- | Build/source/libs/mpfr/mpfr-3.1.2/src/get_ui.c | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/Build/source/libs/mpfr/mpfr-3.1.2/src/get_ui.c b/Build/source/libs/mpfr/mpfr-3.1.2/src/get_ui.c new file mode 100644 index 00000000000..d7b11fe883d --- /dev/null +++ b/Build/source/libs/mpfr/mpfr-3.1.2/src/get_ui.c @@ -0,0 +1,65 @@ +/* mpfr_get_ui -- convert a floating-point number to an unsigned long. + +Copyright 2003, 2004, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 Free Software Foundation, Inc. +Contributed by the AriC 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" + +unsigned long +mpfr_get_ui (mpfr_srcptr f, mpfr_rnd_t rnd) +{ + mpfr_prec_t prec; + unsigned long s; + mpfr_t x; + mp_size_t n; + mpfr_exp_t exp; + + if (MPFR_UNLIKELY (!mpfr_fits_ulong_p (f, rnd))) + { + MPFR_SET_ERANGE (); + return MPFR_IS_NAN (f) || MPFR_IS_NEG (f) ? + (unsigned long) 0 : ULONG_MAX; + } + + if (MPFR_IS_ZERO (f)) + return (unsigned long) 0; + + for (s = ULONG_MAX, prec = 0; s != 0; s /= 2, prec ++) + { } + + /* first round to prec bits */ + mpfr_init2 (x, prec); + mpfr_rint (x, f, rnd); + + /* warning: if x=0, taking its exponent is illegal */ + if (MPFR_IS_ZERO(x)) + s = 0; + else + { + /* now the result is in the most significant limb of x */ + exp = MPFR_GET_EXP (x); /* since |x| >= 1, exp >= 1 */ + n = MPFR_LIMB_SIZE(x); + s = MPFR_MANT(x)[n - 1] >> (GMP_NUMB_BITS - exp); + } + + mpfr_clear (x); + + return s; +} |