summaryrefslogtreecommitdiff
path: root/Build/source/libs/mpfr/mpfr-src/src/exp2.c
diff options
context:
space:
mode:
Diffstat (limited to 'Build/source/libs/mpfr/mpfr-src/src/exp2.c')
-rw-r--r--Build/source/libs/mpfr/mpfr-src/src/exp2.c168
1 files changed, 0 insertions, 168 deletions
diff --git a/Build/source/libs/mpfr/mpfr-src/src/exp2.c b/Build/source/libs/mpfr/mpfr-src/src/exp2.c
deleted file mode 100644
index 087275839c9..00000000000
--- a/Build/source/libs/mpfr/mpfr-src/src/exp2.c
+++ /dev/null
@@ -1,168 +0,0 @@
-/* mpfr_exp2 -- power of 2 function 2^y
-
-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"
-
-/* The computation of y = 2^z is done by *
- * y = exp(z*log(2)). The result is exact iff z is an integer. */
-
-int
-mpfr_exp2 (mpfr_ptr y, mpfr_srcptr x, mpfr_rnd_t rnd_mode)
-{
- int inexact, inex2;
- long xint;
- mpfr_t xfrac;
- MPFR_SAVE_EXPO_DECL (expo);
-
- MPFR_LOG_FUNC
- (("x[%Pu]=%.*Rg rnd=%d", mpfr_get_prec(x), mpfr_log_prec, x, rnd_mode),
- ("y[%Pu]=%.*Rg inexact=%d", mpfr_get_prec(y), mpfr_log_prec, y,
- inexact));
-
- if (MPFR_UNLIKELY (MPFR_IS_SINGULAR (x)))
- {
- if (MPFR_IS_NAN (x))
- {
- MPFR_SET_NAN (y);
- MPFR_RET_NAN;
- }
- else if (MPFR_IS_INF (x))
- {
- if (MPFR_IS_POS (x))
- MPFR_SET_INF (y);
- else
- MPFR_SET_ZERO (y);
- MPFR_SET_POS (y);
- MPFR_RET (0);
- }
- else /* 2^0 = 1 */
- {
- MPFR_ASSERTD (MPFR_IS_ZERO(x));
- return mpfr_set_ui (y, 1, rnd_mode);
- }
- }
-
- /* Since the smallest representable non-zero float is 1/2 * 2^emin,
- if x <= emin - 2, the result is either 1/2 * 2^emin or 0.
- Warning, for emin - 2 < x < emin - 1, we cannot conclude, since 2^x
- might round to 2^(emin - 1) for rounding away or to nearest, and there
- might be no underflow, since we consider underflow "after rounding". */
-
- MPFR_STAT_STATIC_ASSERT (MPFR_EMIN_MIN >= LONG_MIN + 2);
- if (MPFR_UNLIKELY (mpfr_cmp_si (x, __gmpfr_emin - 2) <= 0))
- return mpfr_underflow (y, rnd_mode == MPFR_RNDN ? MPFR_RNDZ : rnd_mode, 1);
-
- MPFR_STAT_STATIC_ASSERT (MPFR_EMAX_MAX <= LONG_MAX);
- if (MPFR_UNLIKELY (mpfr_cmp_si (x, __gmpfr_emax) >= 0))
- return mpfr_overflow (y, rnd_mode, 1);
-
- /* We now know that emin - 2 < x < emax. Note that an underflow or
- overflow is still possible (we have eliminated only easy cases). */
-
- MPFR_SAVE_EXPO_MARK (expo);
-
- /* 2^x = 1 + x*log(2) + O(x^2) for x near zero, and for |x| <= 1 we have
- |2^x - 1| <= x < 2^EXP(x). If x > 0 we must round away from 0 (dir=1);
- if x < 0 we must round toward 0 (dir=0). */
- MPFR_SMALL_INPUT_AFTER_SAVE_EXPO (y, __gmpfr_one, - MPFR_GET_EXP (x), 0,
- MPFR_IS_POS (x), rnd_mode, expo, {});
-
- xint = mpfr_get_si (x, MPFR_RNDZ);
- mpfr_init2 (xfrac, MPFR_PREC (x));
- MPFR_DBGRES (inexact = mpfr_sub_si (xfrac, x, xint, MPFR_RNDN));
- MPFR_ASSERTD (inexact == 0);
-
- if (MPFR_IS_ZERO (xfrac))
- {
- /* Here, emin - 1 <= x <= emax - 1, so that an underflow or overflow
- will not be possible. */
- mpfr_set_ui (y, 1, MPFR_RNDN);
- inexact = 0;
- }
- else
- {
- /* Declaration of the intermediary variable */
- mpfr_t t;
-
- /* Declaration of the size variable */
- mpfr_prec_t Ny = MPFR_PREC(y); /* target precision */
- mpfr_prec_t Nt; /* working precision */
- mpfr_exp_t err; /* error */
- MPFR_ZIV_DECL (loop);
-
- /* compute the precision of intermediary variable */
- /* the optimal number of bits : see algorithms.tex */
- Nt = Ny + 5 + MPFR_INT_CEIL_LOG2 (Ny);
-
- /* initialize of intermediary variable */
- mpfr_init2 (t, Nt);
-
- /* First computation */
- MPFR_ZIV_INIT (loop, Nt);
- for (;;)
- {
- /* compute exp(x*ln(2))*/
- mpfr_const_log2 (t, MPFR_RNDU); /* ln(2) */
- mpfr_mul (t, xfrac, t, MPFR_RNDU); /* xfrac * ln(2) */
- err = Nt - (MPFR_GET_EXP (t) + 2); /* Estimate of the error */
- mpfr_exp (t, t, MPFR_RNDN); /* exp(xfrac * ln(2)) */
-
- if (MPFR_LIKELY (MPFR_CAN_ROUND (t, err, Ny, rnd_mode)))
- break;
-
- /* Actualisation of the precision */
- MPFR_ZIV_NEXT (loop, Nt);
- mpfr_set_prec (t, Nt);
- }
- MPFR_ZIV_FREE (loop);
-
- inexact = mpfr_set (y, t, rnd_mode);
-
- mpfr_clear (t);
- }
-
- mpfr_clear (xfrac);
-
- if (MPFR_UNLIKELY (rnd_mode == MPFR_RNDN && xint == __gmpfr_emin - 1 &&
- MPFR_GET_EXP (y) == 0 && mpfr_powerof2_raw (y)))
- {
- /* y was rounded down to 1/2 and the rounded value with an unbounded
- exponent range would be 2^(emin-2), i.e. the midpoint between 0
- and the smallest positive FP number. This is a double rounding
- problem: we should not round to 0, but to (1/2) * 2^emin. */
- MPFR_SET_EXP (y, __gmpfr_emin);
- inexact = 1;
- MPFR_SAVE_EXPO_UPDATE_FLAGS (expo, MPFR_FLAGS_UNDERFLOW);
- }
- else
- {
- MPFR_CLEAR_FLAGS ();
- inex2 = mpfr_mul_2si (y, y, xint, rnd_mode);
- if (inex2 != 0) /* underflow or overflow */
- inexact = inex2;
- MPFR_SAVE_EXPO_UPDATE_FLAGS (expo, __gmpfr_flags);
- }
-
- MPFR_SAVE_EXPO_FREE (expo);
- return mpfr_check_range (y, inexact, rnd_mode);
-}