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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.
96 lines
3.4 KiB
C
96 lines
3.4 KiB
C
/* mpfr_get_z_2exp -- get a multiple-precision integer and an exponent
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from a floating-point number
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Copyright 2000-2025 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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/* puts the significand of f into z, and returns 'exp' such that f = z * 2^exp
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*
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* 0 doesn't have an exponent, therefore the returned exponent in this case
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* isn't really important. We choose to return __gmpfr_emin because
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* 1) it is in the exponent range [__gmpfr_emin,__gmpfr_emax],
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* 2) the smaller a number is (in absolute value), the smaller its
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* exponent is. In other words, the f -> exp function is monotonous
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* on non-negative numbers. --> This is WRONG since the returned
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* exponent is not necessarily in the exponent range!
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* Note that this is different from the C function frexp().
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*
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* For NaN and infinities, we choose to set z = 0 (neutral value).
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* The exponent doesn't really matter, so let's keep __gmpfr_emin
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* for consistency. The erange flag is set.
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*/
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/* MPFR_LARGE_EXP can be defined when mpfr_exp_t is guaranteed to have
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at least 64 bits (in a portable way). */
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#if GMP_NUMB_BITS >= 64
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/* Now, we know that the constant below is supported by the compiler. */
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# if _MPFR_EXP_FORMAT >= 3 && LONG_MAX >= 9223372036854775807
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# define MPFR_LARGE_EXP 1
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# endif
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#endif
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mpfr_exp_t
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mpfr_get_z_2exp (mpz_ptr z, mpfr_srcptr f)
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{
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mp_size_t fn;
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int sh;
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if (MPFR_UNLIKELY (MPFR_IS_SINGULAR (f)))
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{
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if (MPFR_UNLIKELY (MPFR_NOTZERO (f)))
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MPFR_SET_ERANGEFLAG ();
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mpz_set_ui (z, 0);
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return __gmpfr_emin;
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}
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fn = MPFR_LIMB_SIZE(f);
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/* FIXME: temporary assert for security. Too large values should
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probably be handled like infinities. */
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MPFR_ASSERTN (fn <= INT_MAX); /* due to SIZ(z) being an int */
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/* check whether allocated space for z is enough */
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mpz_realloc2 (z, (mp_bitcnt_t) fn * GMP_NUMB_BITS);
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MPFR_UNSIGNED_MINUS_MODULO (sh, MPFR_PREC (f));
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if (MPFR_LIKELY (sh))
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mpn_rshift (PTR (z), MPFR_MANT (f), fn, sh);
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else
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MPN_COPY (PTR (z), MPFR_MANT (f), fn);
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SIZ(z) = MPFR_IS_NEG (f) ? -fn : fn;
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#ifndef MPFR_LARGE_EXP
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/* If mpfr_exp_t has 64 bits, then MPFR_GET_EXP(f) >= MPFR_EMIN_MIN = 1-2^62
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and MPFR_EXP_MIN <= 1-2^63, thus the following implies PREC(f) > 2^62,
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which is impossible due to memory constraints. */
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if (MPFR_UNLIKELY ((mpfr_uexp_t) MPFR_GET_EXP (f) - MPFR_EXP_MIN
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< (mpfr_uexp_t) MPFR_PREC (f)))
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{
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/* The exponent isn't representable in an mpfr_exp_t. */
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MPFR_SET_ERANGEFLAG ();
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return MPFR_EXP_MIN;
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}
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#endif
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return MPFR_GET_EXP (f) - MPFR_PREC (f);
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}
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