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Diffstat (limited to 'Build/source/libs/mpfr/mpfr-src/src/tanh.c')
-rw-r--r--Build/source/libs/mpfr/mpfr-src/src/tanh.c165
1 files changed, 0 insertions, 165 deletions
diff --git a/Build/source/libs/mpfr/mpfr-src/src/tanh.c b/Build/source/libs/mpfr/mpfr-src/src/tanh.c
deleted file mode 100644
index 29117d7e6ef..00000000000
--- a/Build/source/libs/mpfr/mpfr-src/src/tanh.c
+++ /dev/null
@@ -1,165 +0,0 @@
-/* mpfr_tanh -- hyperbolic tangent
-
-Copyright 2001-2020 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"
-
-int
-mpfr_tanh (mpfr_ptr y, mpfr_srcptr xt , mpfr_rnd_t rnd_mode)
-{
- /****** Declaration ******/
- mpfr_t x;
- int inexact;
- MPFR_SAVE_EXPO_DECL (expo);
-
- MPFR_LOG_FUNC
- (("x[%Pu]=%.*Rg rnd=%d", mpfr_get_prec (xt), mpfr_log_prec, xt, rnd_mode),
- ("y[%Pu]=%.*Rg inexact=%d",
- mpfr_get_prec (y), mpfr_log_prec, y, inexact));
-
- /* Special value checking */
- if (MPFR_UNLIKELY (MPFR_IS_SINGULAR (xt)))
- {
- if (MPFR_IS_NAN (xt))
- {
- MPFR_SET_NAN (y);
- MPFR_RET_NAN;
- }
- else if (MPFR_IS_INF (xt))
- {
- /* tanh(inf) = 1 && tanh(-inf) = -1 */
- return mpfr_set_si (y, MPFR_INT_SIGN (xt), rnd_mode);
- }
- else /* tanh (0) = 0 and xt is zero */
- {
- MPFR_ASSERTD (MPFR_IS_ZERO(xt));
- MPFR_SET_ZERO (y);
- MPFR_SET_SAME_SIGN (y, xt);
- MPFR_RET (0);
- }
- }
-
- /* tanh(x) = x - x^3/3 + ... so the error is < 2^(3*EXP(x)-1) */
- MPFR_FAST_COMPUTE_IF_SMALL_INPUT (y, xt, -2 * MPFR_GET_EXP (xt), 1, 0,
- rnd_mode, {});
-
- MPFR_TMP_INIT_ABS (x, xt);
-
- MPFR_SAVE_EXPO_MARK (expo);
-
- /* General case */
- {
- /* Declaration of the intermediary variable */
- mpfr_t t, te;
- mpfr_exp_t d;
-
- /* Declaration of the size variable */
- mpfr_prec_t Ny = MPFR_PREC(y); /* target precision */
- mpfr_prec_t Nt; /* working precision */
- long int err; /* error */
- int sign = MPFR_SIGN (xt);
- MPFR_ZIV_DECL (loop);
- MPFR_GROUP_DECL (group);
-
- /* First check for BIG overflow of exp(2*x):
- For x > 0, exp(2*x) > 2^(2*x)
- If 2 ^(2*x) > 2^emax or x>emax/2, there is an overflow */
- if (MPFR_UNLIKELY (mpfr_cmp_si (x, __gmpfr_emax/2) >= 0)) {
- /* initialize of intermediary variables
- since 'set_one' label assumes the variables have been
- initialize */
- MPFR_GROUP_INIT_2 (group, MPFR_PREC_MIN, t, te);
- goto set_one;
- }
-
- /* Compute the precision of intermediary variable */
- /* The optimal number of bits: see algorithms.tex */
- Nt = Ny + MPFR_INT_CEIL_LOG2 (Ny) + 4;
- /* if x is small, there will be a cancellation in exp(2x)-1 */
- if (MPFR_GET_EXP (x) < 0)
- Nt += -MPFR_GET_EXP (x);
-
- /* The error analysis in algorithms.tex assumes that x is exactly
- representable with working precision Nt.
- FIXME: adapt the error analysis for the case Nt < PREC(x). */
- if (Nt < MPFR_PREC(x))
- Nt = MPFR_PREC(x);
-
- /* initialize of intermediary variable */
- MPFR_GROUP_INIT_2 (group, Nt, t, te);
-
- MPFR_ZIV_INIT (loop, Nt);
- for (;;)
- {
- /* tanh = (exp(2x)-1)/(exp(2x)+1) */
- inexact = mpfr_mul_2ui (te, x, 1, MPFR_RNDN); /* 2x */
- MPFR_ASSERTD(inexact == 0); /* see FIXME above */
- /* since x > 0, we can only have an overflow */
- mpfr_exp (te, te, MPFR_RNDN); /* exp(2x) */
- if (MPFR_UNLIKELY (MPFR_IS_INF (te)))
- {
- set_one:
- inexact = MPFR_FROM_SIGN_TO_INT (sign);
- mpfr_set4 (y, __gmpfr_one, MPFR_RNDN, sign);
- if (MPFR_IS_LIKE_RNDZ (rnd_mode, MPFR_IS_NEG_SIGN (sign)))
- {
- inexact = -inexact;
- mpfr_nexttozero (y);
- }
- break;
- }
- d = MPFR_GET_EXP (te); /* For Error calculation */
- mpfr_add_ui (t, te, 1, MPFR_RNDD); /* exp(2x) + 1 */
- mpfr_sub_ui (te, te, 1, MPFR_RNDU); /* exp(2x) - 1 */
- d = d - MPFR_GET_EXP (te);
- mpfr_div (t, te, t, MPFR_RNDN); /* (exp(2x)-1)/(exp(2x)+1) */
-
- /* Calculation of the error, see algorithms.tex; the current value
- of d is k in algorithms.tex. */
- d = MAX(3, d + 1); /* d = exponent in 2^(max(3,k+1)) */
- err = Nt - (d + 1);
-
- /* The inequality is the condition max(3,k+1) <= floor(p/2). */
- if (MPFR_LIKELY (d <= Nt / 2 &&
- MPFR_CAN_ROUND (t, err, Ny, rnd_mode)))
- {
- inexact = mpfr_set4 (y, t, rnd_mode, sign);
- break;
- }
-
- /* if t=1, we still can round since |sinh(x)| < 1 */
- if (MPFR_GET_EXP (t) == 1)
- goto set_one;
-
- /* Actualisation of the precision */
- MPFR_ZIV_NEXT (loop, Nt);
- MPFR_GROUP_REPREC_2 (group, Nt, t, te);
- }
- MPFR_ZIV_FREE (loop);
- MPFR_GROUP_CLEAR (group);
- }
- MPFR_SAVE_EXPO_FREE (expo);
- inexact = mpfr_check_range (y, inexact, rnd_mode);
-
- return inexact;
-}
-