51c586b89d
GNU MP is a library for arbitrary precision arithmetic, operating on signed integers, rational numbers, and floating point numbers. It has a rich set of functions, and the functions have a regular interface. GMP is necessary for GCC >= 4.2.
64 lines
1.5 KiB
C
64 lines
1.5 KiB
C
/* mpf_fits_u*_p -- test whether an mpf fits a C unsigned type.
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Copyright 2001, 2002 Free Software Foundation, Inc.
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This file is part of the GNU MP Library.
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The GNU MP Library is free software; you can redistribute it and/or modify
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it under the terms of the GNU Lesser General Public License as published by
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the Free Software Foundation; either version 3 of the License, or (at your
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option) any later version.
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The GNU MP Library is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
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or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
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License for more details.
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You should have received a copy of the GNU Lesser General Public License
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along with the GNU MP Library. If not, see http://www.gnu.org/licenses/. */
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#include "gmp.h"
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#include "gmp-impl.h"
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/* Notice this is equivalent to mpz_set_f + mpz_fits_u*_p. */
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int
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FUNCTION (mpf_srcptr f)
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{
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mp_size_t fn;
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mp_srcptr fp;
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mp_exp_t exp;
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mp_limb_t fl;
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fn = SIZ(f);
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if (fn <= 0)
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return fn == 0; /* zero fits, negatives don't */
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exp = EXP(f);
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if (exp < 1)
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return 1; /* 0 < f < 1 truncates to zero, so fits */
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fp = PTR(f);
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if (exp == 1)
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{
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fl = fp[fn-1];
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}
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#if GMP_NAIL_BITS != 0
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else if (exp == 2 && MAXIMUM > GMP_NUMB_MAX)
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{
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fl = fp[fn-1];
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if ((fl >> GMP_NAIL_BITS) != 0)
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return 0;
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fl = (fl << GMP_NUMB_BITS);
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if (fn >= 2)
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fl |= fp[fn-2];
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}
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#endif
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else
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return 0;
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return fl <= MAXIMUM;
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}
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