vasilito
ff4ff35918
Red Bear OS is a full fork. All sources must be available from git clone with zero network access. Removed gitignore rules that excluded fetched source trees under recipes/*/source/, local/recipes/kde/*/source/, local/recipes/qt/*/source/, and vendor source trees. Build artifacts (target/, build/, source.tar, *.o, *.so) remain excluded. 127291 files added — kernel, relibc, base, bootloader, pkgar, all KDE/Qt frameworks, mesa, wayland, DRM drivers, and every other recipe source.
57 lines
2.0 KiB
C
57 lines
2.0 KiB
C
/* mpfr_extract -- bit-extraction function for the binary splitting algorithm
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Copyright 2000-2002, 2004-2025 Free Software Foundation, Inc.
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Contributed by the Pascaline and Caramba projects, INRIA.
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This file is part of the GNU MPFR Library.
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The GNU MPFR 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 MPFR 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 MPFR Library; see the file COPYING.LESSER.
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If not, see <https://www.gnu.org/licenses/>. */
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#include "mpfr-impl.h"
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/* given 0 <= |p| < 1, this function extracts limbs of p and puts them in y.
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It is mainly designed for the "binary splitting" algorithm.
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More precisely, if B = 2^GMP_NUMB_BITS:
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- for i=0, y = floor(p * B)
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- for i>0, y = (p * B^(2^i)) mod B^(2^(i-1))
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*/
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void
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mpfr_extract (mpz_ptr y, mpfr_srcptr p, unsigned int i)
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{
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unsigned long two_i = 1UL << i;
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unsigned long two_i_2 = i ? two_i / 2 : 1;
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mp_size_t size_p = MPFR_LIMB_SIZE (p);
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MPFR_ASSERTN (two_i != 0 && two_i_2 <= INT_MAX); /* overflow check */
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/* as 0 <= |p| < 1, we don't have to care with infinities, NaN, ... */
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MPFR_ASSERTD (!MPFR_IS_SINGULAR (p));
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mpz_realloc2 (y, (mp_bitcnt_t) two_i_2 * GMP_NUMB_BITS);
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if (size_p < two_i)
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{
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MPN_ZERO (PTR(y), two_i_2);
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if (size_p >= two_i_2)
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MPN_COPY (PTR(y) + (two_i - size_p), MPFR_MANT(p), size_p - two_i_2);
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}
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else
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MPN_COPY (PTR(y), MPFR_MANT(p) + size_p - two_i, two_i_2);
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MPN_NORMALIZE (PTR(y), two_i_2);
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SIZ(y) = MPFR_IS_NEG (p) ? - (int) two_i_2 : (int) two_i_2;
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}
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