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-rw-r--r--Build/source/libs/mpfr/mpfr-src/src/const_pi.c122
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diff --git a/Build/source/libs/mpfr/mpfr-src/src/const_pi.c b/Build/source/libs/mpfr/mpfr-src/src/const_pi.c
deleted file mode 100644
index 26c55030d28..00000000000
--- a/Build/source/libs/mpfr/mpfr-src/src/const_pi.c
+++ /dev/null
@@ -1,122 +0,0 @@
-/* mpfr_const_pi -- compute Pi
-
-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. */
-
-#include "mpfr-impl.h"
-
-/* Declare the cache */
-#ifndef MPFR_USE_LOGGING
-MPFR_DECL_INIT_CACHE (__gmpfr_cache_const_pi, mpfr_const_pi_internal)
-#else
-MPFR_DECL_INIT_CACHE (__gmpfr_normal_pi, mpfr_const_pi_internal)
-MPFR_DECL_INIT_CACHE (__gmpfr_logging_pi, mpfr_const_pi_internal)
-MPFR_THREAD_VAR (mpfr_cache_ptr, __gmpfr_cache_const_pi, __gmpfr_normal_pi)
-#endif
-
-/* Set User Interface */
-#undef mpfr_const_pi
-int
-mpfr_const_pi (mpfr_ptr x, mpfr_rnd_t rnd_mode) {
- return mpfr_cache (x, __gmpfr_cache_const_pi, rnd_mode);
-}
-
-/* The algorithm used here is taken from Section 8.2.5 of the book
- "Fast Algorithms: A Multitape Turing Machine Implementation"
- by A. Schönhage, A. F. W. Grotefeld and E. Vetter, 1994.
- It is a clever form of Brent-Salamin formula. */
-
-/* Don't need to save/restore exponent range: the cache does it */
-int
-mpfr_const_pi_internal (mpfr_ptr x, mpfr_rnd_t rnd_mode)
-{
- mpfr_t a, A, B, D, S;
- mpfr_prec_t px, p, cancel, k, kmax;
- MPFR_GROUP_DECL (group);
- MPFR_ZIV_DECL (loop);
- int inex;
-
- MPFR_LOG_FUNC
- (("rnd_mode=%d", rnd_mode),
- ("x[%Pu]=%.*Rg inexact=%d", mpfr_get_prec(x), mpfr_log_prec, x, inex));
-
- px = MPFR_PREC (x);
-
- /* we need 9*2^kmax - 4 >= px+2*kmax+8 */
- for (kmax = 2; ((px + 2 * kmax + 12) / 9) >> kmax; kmax ++);
-
- p = px + 3 * kmax + 14; /* guarantees no recomputation for px <= 10000 */
-
- MPFR_GROUP_INIT_5 (group, p, a, A, B, D, S);
-
- MPFR_ZIV_INIT (loop, p);
- for (;;) {
- mpfr_set_ui (a, 1, MPFR_RNDN); /* a = 1 */
- mpfr_set_ui (A, 1, MPFR_RNDN); /* A = a^2 = 1 */
- mpfr_set_ui_2exp (B, 1, -1, MPFR_RNDN); /* B = b^2 = 1/2 */
- mpfr_set_ui_2exp (D, 1, -2, MPFR_RNDN); /* D = 1/4 */
-
-#define b B
-#define ap a
-#define Ap A
-#define Bp B
- for (k = 0; ; k++)
- {
- /* invariant: 1/2 <= B <= A <= a < 1 */
- mpfr_add (S, A, B, MPFR_RNDN); /* 1 <= S <= 2 */
- mpfr_div_2ui (S, S, 2, MPFR_RNDN); /* exact, 1/4 <= S <= 1/2 */
- mpfr_sqrt (b, B, MPFR_RNDN); /* 1/2 <= b <= 1 */
- mpfr_add (ap, a, b, MPFR_RNDN); /* 1 <= ap <= 2 */
- mpfr_div_2ui (ap, ap, 1, MPFR_RNDN); /* exact, 1/2 <= ap <= 1 */
- mpfr_sqr (Ap, ap, MPFR_RNDN); /* 1/4 <= Ap <= 1 */
- mpfr_sub (Bp, Ap, S, MPFR_RNDN); /* -1/4 <= Bp <= 3/4 */
- mpfr_mul_2ui (Bp, Bp, 1, MPFR_RNDN); /* -1/2 <= Bp <= 3/2 */
- mpfr_sub (S, Ap, Bp, MPFR_RNDN);
- MPFR_ASSERTD (mpfr_cmp_ui (S, 1) < 0);
- cancel = MPFR_NOTZERO (S) ? (mpfr_uexp_t) -mpfr_get_exp(S) : p;
- /* MPFR_ASSERTN (cancel >= px || cancel >= 9 * (1 << k) - 4); */
- mpfr_mul_2ui (S, S, k, MPFR_RNDN);
- mpfr_sub (D, D, S, MPFR_RNDN);
- /* stop when |A_k - B_k| <= 2^(k-p) i.e. cancel >= p-k */
- if (cancel >= p - k)
- break;
- }
-#undef b
-#undef ap
-#undef Ap
-#undef Bp
-
- mpfr_div (A, B, D, MPFR_RNDN);
-
- /* MPFR_ASSERTN(p >= 2 * k + 8); */
- if (MPFR_LIKELY (MPFR_CAN_ROUND (A, p - 2 * k - 8, px, rnd_mode)))
- break;
-
- p += kmax;
- MPFR_ZIV_NEXT (loop, p);
- MPFR_GROUP_REPREC_5 (group, p, a, A, B, D, S);
- }
- MPFR_ZIV_FREE (loop);
- inex = mpfr_set (x, A, rnd_mode);
-
- MPFR_GROUP_CLEAR (group);
-
- return inex;
-}