14a238c70SJohn Marino /* mpfr_integer_p -- test if a mpfr variable is integer.
24a238c70SJohn Marino
3*ab6d115fSJohn Marino Copyright 2001, 2002, 2003, 2004, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 Free Software Foundation, Inc.
4*ab6d115fSJohn Marino Contributed by the AriC and Caramel projects, INRIA.
54a238c70SJohn Marino
64a238c70SJohn Marino This file is part of the GNU MPFR Library.
74a238c70SJohn Marino
84a238c70SJohn Marino The GNU MPFR Library is free software; you can redistribute it and/or modify
94a238c70SJohn Marino it under the terms of the GNU Lesser General Public License as published by
104a238c70SJohn Marino the Free Software Foundation; either version 3 of the License, or (at your
114a238c70SJohn Marino option) any later version.
124a238c70SJohn Marino
134a238c70SJohn Marino The GNU MPFR Library is distributed in the hope that it will be useful, but
144a238c70SJohn Marino WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
154a238c70SJohn Marino or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
164a238c70SJohn Marino License for more details.
174a238c70SJohn Marino
184a238c70SJohn Marino You should have received a copy of the GNU Lesser General Public License
194a238c70SJohn Marino along with the GNU MPFR Library; see the file COPYING.LESSER. If not, see
204a238c70SJohn Marino http://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
214a238c70SJohn Marino 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */
224a238c70SJohn Marino
234a238c70SJohn Marino
244a238c70SJohn Marino #include "mpfr-impl.h"
254a238c70SJohn Marino
264a238c70SJohn Marino int
mpfr_integer_p(mpfr_srcptr x)274a238c70SJohn Marino mpfr_integer_p (mpfr_srcptr x)
284a238c70SJohn Marino {
294a238c70SJohn Marino mpfr_exp_t expo;
304a238c70SJohn Marino mpfr_prec_t prec;
314a238c70SJohn Marino mp_size_t xn;
324a238c70SJohn Marino mp_limb_t *xp;
334a238c70SJohn Marino
344a238c70SJohn Marino if (MPFR_UNLIKELY( MPFR_IS_SINGULAR(x)))
354a238c70SJohn Marino return (MPFR_IS_ZERO(x));
364a238c70SJohn Marino
374a238c70SJohn Marino expo = MPFR_GET_EXP (x);
384a238c70SJohn Marino if (expo <= 0)
394a238c70SJohn Marino return 0;
404a238c70SJohn Marino
414a238c70SJohn Marino prec = MPFR_PREC(x);
424a238c70SJohn Marino if ((mpfr_uexp_t) expo >= (mpfr_uexp_t) prec)
434a238c70SJohn Marino return 1;
444a238c70SJohn Marino
454a238c70SJohn Marino /* 0 < expo < prec */
464a238c70SJohn Marino
474a238c70SJohn Marino xn = (mp_size_t) ((prec - 1) / GMP_NUMB_BITS); /* index of last limb */
484a238c70SJohn Marino xn -= (mp_size_t) (expo / GMP_NUMB_BITS);
494a238c70SJohn Marino /* now the index of the last limb containing bits of the fractional part */
504a238c70SJohn Marino
514a238c70SJohn Marino xp = MPFR_MANT(x);
524a238c70SJohn Marino MPFR_ASSERTN(xn >= 0);
534a238c70SJohn Marino if (xp[xn] << (expo % GMP_NUMB_BITS) != 0)
544a238c70SJohn Marino return 0;
554a238c70SJohn Marino while (--xn >= 0)
564a238c70SJohn Marino if (xp[xn] != 0)
574a238c70SJohn Marino return 0;
584a238c70SJohn Marino return 1;
594a238c70SJohn Marino }
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