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-rw-r--r--Build/source/libs/mpfr/mpfr-src/src/log.c191
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diff --git a/Build/source/libs/mpfr/mpfr-src/src/log.c b/Build/source/libs/mpfr/mpfr-src/src/log.c
deleted file mode 100644
index 30e8cb2fe76..00000000000
--- a/Build/source/libs/mpfr/mpfr-src/src/log.c
+++ /dev/null
@@ -1,191 +0,0 @@
-/* mpfr_log -- natural logarithm of a floating-point number
-
-Copyright 1999-2020 Free Software Foundation, Inc.
-Contributed by the AriC and Caramba projects, INRIA.
-
-This file is part of the GNU MPFR Library.
-
-The GNU MPFR Library is free software; you can redistribute it and/or modify
-it under the terms of the GNU Lesser General Public License as published by
-the Free Software Foundation; either version 3 of the License, or (at your
-option) any later version.
-
-The GNU MPFR Library is distributed in the hope that it will be useful, but
-WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
-or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
-License for more details.
-
-You should have received a copy of the GNU Lesser General Public License
-along with the GNU MPFR Library; see the file COPYING.LESSER. If not, see
-https://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
-51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */
-
-#define MPFR_NEED_LONGLONG_H
-#include "mpfr-impl.h"
-
-/* The computation of log(x) is done using the formula :
- if we want p bits of the result,
-
- pi
- log(x) ~ ------------ - m log 2
- 2 AG(1,4/s)
-
- where s = x 2^m > 2^(p/2)
-
- More precisely, if F(x) = int(1/sqrt(1-(1-x^2)*sin(t)^2), t=0..PI/2),
- then for s>=1.26 we have log(s) < F(4/s) < log(s)*(1+4/s^2)
- from which we deduce pi/2/AG(1,4/s)*(1-4/s^2) < log(s) < pi/2/AG(1,4/s)
- so the relative error 4/s^2 is < 4/2^p i.e. 4 ulps.
-*/
-
-int
-mpfr_log (mpfr_ptr r, mpfr_srcptr a, mpfr_rnd_t rnd_mode)
-{
- int inexact;
- mpfr_prec_t p, q;
- mpfr_t tmp1, tmp2;
- mpfr_exp_t exp_a;
- MPFR_SAVE_EXPO_DECL (expo);
- MPFR_ZIV_DECL (loop);
- MPFR_GROUP_DECL(group);
-
- MPFR_LOG_FUNC
- (("a[%Pu]=%.*Rg rnd=%d", mpfr_get_prec (a), mpfr_log_prec, a, rnd_mode),
- ("r[%Pu]=%.*Rg inexact=%d", mpfr_get_prec (r), mpfr_log_prec, r,
- inexact));
-
- /* Special cases */
- if (MPFR_UNLIKELY (MPFR_IS_SINGULAR (a)))
- {
- /* If a is NaN, the result is NaN */
- if (MPFR_IS_NAN (a))
- {
- MPFR_SET_NAN (r);
- MPFR_RET_NAN;
- }
- /* check for infinity before zero */
- else if (MPFR_IS_INF (a))
- {
- if (MPFR_IS_NEG (a))
- /* log(-Inf) = NaN */
- {
- MPFR_SET_NAN (r);
- MPFR_RET_NAN;
- }
- else /* log(+Inf) = +Inf */
- {
- MPFR_SET_INF (r);
- MPFR_SET_POS (r);
- MPFR_RET (0);
- }
- }
- else /* a is zero */
- {
- MPFR_ASSERTD (MPFR_IS_ZERO (a));
- MPFR_SET_INF (r);
- MPFR_SET_NEG (r);
- MPFR_SET_DIVBY0 ();
- MPFR_RET (0); /* log(0) is an exact -infinity */
- }
- }
-
- /* If a is negative, the result is NaN */
- if (MPFR_UNLIKELY (MPFR_IS_NEG (a)))
- {
- MPFR_SET_NAN (r);
- MPFR_RET_NAN;
- }
-
- exp_a = MPFR_GET_EXP (a);
-
- /* If a is 1, the result is +0 */
- if (MPFR_UNLIKELY (exp_a == 1 && mpfr_cmp_ui (a, 1) == 0))
- {
- MPFR_SET_ZERO (r);
- MPFR_SET_POS (r);
- MPFR_RET (0); /* only "normal" case where the result is exact */
- }
-
- q = MPFR_PREC (r);
-
- /* use initial precision about q+2*lg(q)+cte */
- p = q + 2 * MPFR_INT_CEIL_LOG2 (q) + 10;
- /* % ~(mpfr_prec_t)GMP_NUMB_BITS ;
- m=q; while (m) { p++; m >>= 1; } */
- /* if (MPFR_LIKELY(p % GMP_NUMB_BITS != 0))
- p += GMP_NUMB_BITS - (p%GMP_NUMB_BITS); */
-
- MPFR_SAVE_EXPO_MARK (expo);
- MPFR_GROUP_INIT_2 (group, p, tmp1, tmp2);
-
- MPFR_ZIV_INIT (loop, p);
- for (;;)
- {
- mpfr_exp_t m;
- mpfr_exp_t cancel;
-
- /* Calculus of m (depends on p)
- If mpfr_exp_t has N bits, then both (p + 3) / 2 and |exp_a| fit
- on N-2 bits, so that there cannot be an overflow. */
- m = (p + 3) / 2 - exp_a;
-
- /* In standard configuration (_MPFR_EXP_FORMAT <= 3), one has
- mpfr_exp_t <= long, so that the following assertion is always
- true. */
- MPFR_ASSERTN (m >= LONG_MIN && m <= LONG_MAX);
-
- /* FIXME: Why 1 ulp and not 1/2 ulp? Ditto with some other ones
- below. The error concerning the AGM should be explained since
- 4/s is inexact (one needs a bound on its derivative). */
- mpfr_mul_2si (tmp2, a, m, MPFR_RNDN); /* s=a*2^m, err<=1 ulp */
- MPFR_ASSERTD (MPFR_EXP (tmp2) >= (p + 3) / 2);
- /* [FIXME] and one can have the equality, even if p is even.
- This means that if a is a power of 2 and p is even, then
- s = (1/2) * 2^((p+2)/2) = 2^(p/2), so that the condition
- s > 2^(p/2) from algorithms.tex is not satisfied. */
- mpfr_div (tmp1, __gmpfr_four, tmp2, MPFR_RNDN);/* 4/s, err<=2 ulps */
- mpfr_agm (tmp2, __gmpfr_one, tmp1, MPFR_RNDN); /* AG(1,4/s),err<=3 ulps */
- mpfr_mul_2ui (tmp2, tmp2, 1, MPFR_RNDN); /* 2*AG(1,4/s), err<=3 ulps */
- mpfr_const_pi (tmp1, MPFR_RNDN); /* compute pi, err<=1ulp */
- mpfr_div (tmp2, tmp1, tmp2, MPFR_RNDN); /* pi/2*AG(1,4/s), err<=5ulps */
- mpfr_const_log2 (tmp1, MPFR_RNDN); /* compute log(2), err<=1ulp */
- mpfr_mul_si (tmp1, tmp1, m, MPFR_RNDN); /* compute m*log(2),err<=2ulps */
- mpfr_sub (tmp1, tmp2, tmp1, MPFR_RNDN); /* log(a), err<=7ulps+cancel */
-
- if (MPFR_LIKELY (MPFR_IS_PURE_FP (tmp1) && MPFR_IS_PURE_FP (tmp2)))
- {
- cancel = MPFR_GET_EXP (tmp2) - MPFR_GET_EXP (tmp1);
- MPFR_LOG_MSG (("canceled bits=%ld\n", (long) cancel));
- MPFR_LOG_VAR (tmp1);
- if (MPFR_UNLIKELY (cancel < 0))
- cancel = 0;
-
- /* we have 7 ulps of error from the above roundings,
- 4 ulps from the 4/s^2 second order term,
- plus the canceled bits */
- if (MPFR_LIKELY (MPFR_CAN_ROUND (tmp1, p - cancel - 4, q, rnd_mode)))
- break;
-
- /* VL: I think it is better to have an increment that it isn't
- too low; in particular, the increment must be positive even
- if cancel = 0 (can this occur?). */
- p += cancel + MPFR_INT_CEIL_LOG2 (p);
- }
- else
- {
- /* TODO: find why this case can occur and what is best to do
- with it. */
- p += MPFR_INT_CEIL_LOG2 (p);
- }
-
- MPFR_ZIV_NEXT (loop, p);
- MPFR_GROUP_REPREC_2 (group, p, tmp1, tmp2);
- }
- MPFR_ZIV_FREE (loop);
- inexact = mpfr_set (r, tmp1, rnd_mode);
- /* We clean */
- MPFR_GROUP_CLEAR (group);
-
- MPFR_SAVE_EXPO_FREE (expo);
- return mpfr_check_range (r, inexact, rnd_mode);
-}