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-rw-r--r--Build/source/libs/mpfr/mpfr-src/src/pow_si.c249
1 files changed, 0 insertions, 249 deletions
diff --git a/Build/source/libs/mpfr/mpfr-src/src/pow_si.c b/Build/source/libs/mpfr/mpfr-src/src/pow_si.c
deleted file mode 100644
index 081580e1ca4..00000000000
--- a/Build/source/libs/mpfr/mpfr-src/src/pow_si.c
+++ /dev/null
@@ -1,249 +0,0 @@
-/* mpfr_pow_si -- power function x^y with y a signed int
-
-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 /* for MPFR_INT_CEIL_LOG2 */
-#include "mpfr-impl.h"
-
-/* The computation of y = pow_si(x,n) is done by
- * y = pow_ui(x,n) if n >= 0
- * y = 1 / pow_ui(x,-n) if n < 0
- */
-
-int
-mpfr_pow_si (mpfr_ptr y, mpfr_srcptr x, long int n, mpfr_rnd_t rnd)
-{
- MPFR_LOG_FUNC
- (("x[%Pu]=%.*Rg n=%ld rnd=%d",
- mpfr_get_prec (x), mpfr_log_prec, x, n, rnd),
- ("y[%Pu]=%.*Rg", mpfr_get_prec (y), mpfr_log_prec, y));
-
- if (n >= 0)
- return mpfr_pow_ui (y, x, n, rnd);
- else
- {
- if (MPFR_UNLIKELY (MPFR_IS_SINGULAR (x)))
- {
- if (MPFR_IS_NAN (x))
- {
- MPFR_SET_NAN (y);
- MPFR_RET_NAN;
- }
- else
- {
- int positive = MPFR_IS_POS (x) || ((unsigned long) n & 1) == 0;
- if (MPFR_IS_INF (x))
- MPFR_SET_ZERO (y);
- else /* x is zero */
- {
- MPFR_ASSERTD (MPFR_IS_ZERO (x));
- MPFR_SET_INF (y);
- MPFR_SET_DIVBY0 ();
- }
- if (positive)
- MPFR_SET_POS (y);
- else
- MPFR_SET_NEG (y);
- MPFR_RET (0);
- }
- }
-
- /* detect exact powers: x^(-n) is exact iff x is a power of 2 */
- if (mpfr_cmp_si_2exp (x, MPFR_SIGN(x), MPFR_EXP(x) - 1) == 0)
- {
- mpfr_exp_t expx = MPFR_EXP (x) - 1, expy;
- MPFR_ASSERTD (n < 0);
- /* Warning: n * expx may overflow!
- *
- * Some systems (apparently alpha-freebsd) abort with
- * LONG_MIN / 1, and LONG_MIN / -1 is undefined.
- * http://www.freebsd.org/cgi/query-pr.cgi?pr=72024
- *
- * Proof of the overflow checking. The expressions below are
- * assumed to be on the rational numbers, but the word "overflow"
- * still has its own meaning in the C context. / still denotes
- * the integer (truncated) division, and // denotes the exact
- * division.
- * - First, (__gmpfr_emin - 1) / n and (__gmpfr_emax - 1) / n
- * cannot overflow due to the constraints on the exponents of
- * MPFR numbers.
- * - If n = -1, then n * expx = - expx, which is representable
- * because of the constraints on the exponents of MPFR numbers.
- * - If expx = 0, then n * expx = 0, which is representable.
- * - If n < -1 and expx > 0:
- * + If expx > (__gmpfr_emin - 1) / n, then
- * expx >= (__gmpfr_emin - 1) / n + 1
- * > (__gmpfr_emin - 1) // n,
- * and
- * n * expx < __gmpfr_emin - 1,
- * i.e.
- * n * expx <= __gmpfr_emin - 2.
- * This corresponds to an underflow, with a null result in
- * the rounding-to-nearest mode.
- * + If expx <= (__gmpfr_emin - 1) / n, then n * expx cannot
- * overflow since 0 < expx <= (__gmpfr_emin - 1) / n and
- * 0 > n * expx >= n * ((__gmpfr_emin - 1) / n)
- * >= __gmpfr_emin - 1.
- * - If n < -1 and expx < 0:
- * + If expx < (__gmpfr_emax - 1) / n, then
- * expx <= (__gmpfr_emax - 1) / n - 1
- * < (__gmpfr_emax - 1) // n,
- * and
- * n * expx > __gmpfr_emax - 1,
- * i.e.
- * n * expx >= __gmpfr_emax.
- * This corresponds to an overflow (2^(n * expx) has an
- * exponent > __gmpfr_emax).
- * + If expx >= (__gmpfr_emax - 1) / n, then n * expx cannot
- * overflow since 0 > expx >= (__gmpfr_emax - 1) / n and
- * 0 < n * expx <= n * ((__gmpfr_emax - 1) / n)
- * <= __gmpfr_emax - 1.
- * Note: one could use expx bounds based on MPFR_EXP_MIN and
- * MPFR_EXP_MAX instead of __gmpfr_emin and __gmpfr_emax. The
- * current bounds do not lead to noticeably slower code and
- * allow us to avoid a bug in Sun's compiler for Solaris/x86
- * (when optimizations are enabled); known affected versions:
- * cc: Sun C 5.8 2005/10/13
- * cc: Sun C 5.8 Patch 121016-02 2006/03/31
- * cc: Sun C 5.8 Patch 121016-04 2006/10/18
- */
- expy =
- n != -1 && expx > 0 && expx > (__gmpfr_emin - 1) / n ?
- MPFR_EMIN_MIN - 2 /* Underflow */ :
- n != -1 && expx < 0 && expx < (__gmpfr_emax - 1) / n ?
- MPFR_EMAX_MAX /* Overflow */ : n * expx;
- return mpfr_set_si_2exp (y, n % 2 ? MPFR_INT_SIGN (x) : 1,
- expy, rnd);
- }
-
- /* General case */
- {
- /* Declaration of the intermediary variable */
- mpfr_t t;
- /* Declaration of the size variable */
- mpfr_prec_t Ny; /* target precision */
- mpfr_prec_t Nt; /* working precision */
- mpfr_rnd_t rnd1;
- int size_n;
- int inexact;
- unsigned long abs_n;
- MPFR_SAVE_EXPO_DECL (expo);
- MPFR_ZIV_DECL (loop);
-
- abs_n = - (unsigned long) n;
- size_n = mpfr_nbits_ulong (abs_n);
-
- /* initial working precision */
- Ny = MPFR_PREC (y);
- Nt = Ny + size_n + 3 + MPFR_INT_CEIL_LOG2 (Ny);
-
- MPFR_SAVE_EXPO_MARK (expo);
-
- /* initialize of intermediary variable */
- mpfr_init2 (t, Nt);
-
- /* We will compute rnd(rnd1(1/x) ^ |n|), where rnd1 is the rounding
- toward sign(x), to avoid spurious overflow or underflow, as in
- mpfr_pow_z. */
- rnd1 = MPFR_EXP (x) < 1 ? MPFR_RNDZ :
- (MPFR_IS_POS (x) ? MPFR_RNDU : MPFR_RNDD);
-
- MPFR_ZIV_INIT (loop, Nt);
- for (;;)
- {
- MPFR_BLOCK_DECL (flags);
-
- /* compute (1/x)^|n| */
- MPFR_BLOCK (flags, mpfr_ui_div (t, 1, x, rnd1));
- MPFR_ASSERTD (! MPFR_UNDERFLOW (flags));
- /* t = (1/x)*(1+theta) where |theta| <= 2^(-Nt) */
- if (MPFR_UNLIKELY (MPFR_OVERFLOW (flags)))
- goto overflow;
- MPFR_BLOCK (flags, mpfr_pow_ui (t, t, abs_n, rnd));
- /* t = (1/x)^|n|*(1+theta')^(|n|+1) where |theta'| <= 2^(-Nt).
- If (|n|+1)*2^(-Nt) <= 1/2, which is satisfied as soon as
- Nt >= bits(n)+2, then we can use Lemma \ref{lemma_graillat}
- from algorithms.tex, which yields x^n*(1+theta) with
- |theta| <= 2(|n|+1)*2^(-Nt), thus the error is bounded by
- 2(|n|+1) ulps <= 2^(bits(n)+2) ulps. */
- if (MPFR_UNLIKELY (MPFR_OVERFLOW (flags)))
- {
- overflow:
- MPFR_ZIV_FREE (loop);
- mpfr_clear (t);
- MPFR_SAVE_EXPO_FREE (expo);
- MPFR_LOG_MSG (("overflow\n", 0));
- return mpfr_overflow (y, rnd, abs_n & 1 ?
- MPFR_SIGN (x) : MPFR_SIGN_POS);
- }
- if (MPFR_UNLIKELY (MPFR_UNDERFLOW (flags)))
- {
- MPFR_ZIV_FREE (loop);
- mpfr_clear (t);
- MPFR_LOG_MSG (("underflow\n", 0));
- if (rnd == MPFR_RNDN)
- {
- mpfr_t y2, nn;
-
- /* We cannot decide now whether the result should be
- rounded toward zero or away from zero. So, like
- in mpfr_pow_pos_z, let's use the general case of
- mpfr_pow in precision 2. */
- MPFR_ASSERTD (mpfr_cmp_si_2exp (x, MPFR_SIGN (x),
- MPFR_EXP (x) - 1) != 0);
- mpfr_init2 (y2, 2);
- mpfr_init2 (nn, sizeof (long) * CHAR_BIT);
- inexact = mpfr_set_si (nn, n, MPFR_RNDN);
- MPFR_ASSERTN (inexact == 0);
- inexact = mpfr_pow_general (y2, x, nn, rnd, 1,
- (mpfr_save_expo_t *) NULL);
- mpfr_clear (nn);
- mpfr_set (y, y2, MPFR_RNDN);
- mpfr_clear (y2);
- MPFR_SAVE_EXPO_UPDATE_FLAGS (expo, MPFR_FLAGS_UNDERFLOW);
- goto end;
- }
- else
- {
- MPFR_SAVE_EXPO_FREE (expo);
- return mpfr_underflow (y, rnd, abs_n & 1 ?
- MPFR_SIGN (x) : MPFR_SIGN_POS);
- }
- }
- /* error estimate -- see pow function in algorithms.ps */
- if (MPFR_LIKELY (MPFR_CAN_ROUND (t, Nt - size_n - 2, Ny, rnd)))
- break;
-
- /* actualization of the precision */
- MPFR_ZIV_NEXT (loop, Nt);
- mpfr_set_prec (t, Nt);
- }
- MPFR_ZIV_FREE (loop);
-
- inexact = mpfr_set (y, t, rnd);
- mpfr_clear (t);
-
- end:
- MPFR_SAVE_EXPO_FREE (expo);
- return mpfr_check_range (y, inexact, rnd);
- }
- }
-}