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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.
69 lines
2.6 KiB
C
69 lines
2.6 KiB
C
/* mpfr_div_2ui -- divide a floating-point number by a power of two
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Copyright 1999, 2001-2025 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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int
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mpfr_div_2ui (mpfr_ptr y, mpfr_srcptr x, unsigned long n, mpfr_rnd_t rnd_mode)
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{
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int inexact;
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MPFR_LOG_FUNC (
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("x[%Pd]=%.*Rg n=%lu rnd=%d", mpfr_get_prec(x), mpfr_log_prec, x, n,
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rnd_mode),
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("y[%Pd]=%.*Rg inexact=%d", mpfr_get_prec(y), mpfr_log_prec, y, inexact));
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if (MPFR_UNLIKELY (n == 0 || MPFR_IS_SINGULAR (x)))
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return mpfr_set (y, x, rnd_mode);
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else
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{
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mpfr_exp_t exp = MPFR_GET_EXP (x);
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mpfr_uexp_t diffexp;
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MPFR_SETRAW (inexact, y, x, exp, rnd_mode);
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/* Warning! exp may have increased by 1 due to rounding. Thus the
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difference below may overflow in a mpfr_exp_t; but mpfr_uexp_t
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is OK to hold the value, with the difference done in unsigned
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integer arithmetic in this type. */
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diffexp = (mpfr_uexp_t) exp - (mpfr_uexp_t) (__gmpfr_emin - 1);
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if (MPFR_UNLIKELY (n >= diffexp)) /* exp - n <= emin - 1 */
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{
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if (rnd_mode == MPFR_RNDN &&
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(n > diffexp ||
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((MPFR_IS_NEG (y) ? inexact <= 0 : inexact >= 0) &&
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mpfr_powerof2_raw (y))))
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rnd_mode = MPFR_RNDZ;
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return mpfr_underflow (y, rnd_mode, MPFR_SIGN (y));
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}
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/* Now, n < diffexp, i.e. n <= exp - emin, which a difference of
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* two valid exponents + 0 or 1, thus fits in a mpfr_exp_t (from
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* the constraints on valid exponents). Moreover, there cannot be
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* an overflow (if exp had been increased by 1 due to rounding)
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* since the case n = 0 has been filtered out.
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*/
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MPFR_ASSERTD (n <= MPFR_EXP_MAX);
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MPFR_ASSERTD (n >= 1);
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MPFR_SET_EXP (y, exp - (mpfr_exp_t) n);
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}
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MPFR_RET (inexact);
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}
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