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-rw-r--r--Build/source/libs/mpfr/mpfr-src/src/mpn_exp.c206
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diff --git a/Build/source/libs/mpfr/mpfr-src/src/mpn_exp.c b/Build/source/libs/mpfr/mpfr-src/src/mpn_exp.c
deleted file mode 100644
index 983dc77a4a6..00000000000
--- a/Build/source/libs/mpfr/mpfr-src/src/mpn_exp.c
+++ /dev/null
@@ -1,206 +0,0 @@
-/* mpfr_mpn_exp -- auxiliary function for mpfr_get_str and mpfr_set_str
-
-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"
-
-/* count the number of significant bits of e, i.e.,
- nbits(mpfr_exp_t) - count_leading_zeros (e) */
-static int
-nbits_mpfr_exp_t (mpfr_exp_t e)
-{
- int nbits = 0;
-
- MPFR_ASSERTD (e > 0);
- while (e >= 0x10000)
- {
- e >>= 16;
- nbits += 16;
- }
- MPFR_ASSERTD (e <= 0xffff);
- if (e >= 0x100)
- {
- e >>= 8;
- nbits += 8;
- }
- MPFR_ASSERTD (e <= 0xff);
- if (e >= 0x10)
- {
- e >>= 4;
- nbits += 4;
- }
- MPFR_ASSERTD (e <= 0xf);
- if (e >= 4)
- {
- e >>= 2;
- nbits += 2;
- }
- MPFR_ASSERTD (e <= 3);
- /* now e = 1, 2, or 3 */
- return nbits + 1 + (e >= 2);
-}
-
-/* this function computes an approximation to b^e in {a, n}, with exponent
- stored in exp_r. The computed value is rounded toward zero (truncated).
- It returns an integer f such that the final error is bounded by 2^f ulps,
- that is:
- a*2^exp_r <= b^e <= 2^exp_r (a + 2^f),
- where a represents {a, n}, i.e. the integer
- a[0] + a[1]*B + ... + a[n-1]*B^(n-1) where B=2^GMP_NUMB_BITS
-
- Return -1 is the result is exact.
- Return -2 if an overflow occurred in the computation of exp_r.
-*/
-
-int
-mpfr_mpn_exp (mp_limb_t *a, mpfr_exp_t *exp_r, int b, mpfr_exp_t e, size_t n)
-{
- mp_limb_t *c, B;
- mpfr_exp_t f, h;
- int i;
- int t; /* number of bits in e */
- size_t bits, n1;
- unsigned int error; /* (number - 1) of loops a^2b inexact */
- /* error == t means no error */
- int err_s_a2 = 0;
- int err_s_ab = 0; /* number of error when shift A^2, AB */
- MPFR_TMP_DECL(marker);
-
- MPFR_ASSERTN (n > 0 && n <= ((size_t) -1) / GMP_NUMB_BITS);
- MPFR_ASSERTN (e > 0);
- MPFR_ASSERTN (2 <= b && b <= 62);
-
- MPFR_TMP_MARK(marker);
-
- /* initialization of a, b, f, h */
-
- /* normalize the base */
- B = (mp_limb_t) b;
- count_leading_zeros (h, B);
-
- bits = GMP_NUMB_BITS - h;
-
- B = B << h;
- h = - h;
-
- /* allocate space for A and set it to B */
- c = MPFR_TMP_LIMBS_ALLOC (2 * n);
- a [n - 1] = B;
- MPN_ZERO (a, n - 1);
- /* initial exponent for A: invariant is A = {a, n} * 2^f */
- f = h - (n - 1) * GMP_NUMB_BITS;
-
- /* determine number of bits in e */
- t = nbits_mpfr_exp_t (e);
-
- error = t;
- /* t, error <= bitsize(mpfr_exp_t) */
- MPFR_ASSERTD (error >= 0);
-
- MPN_ZERO (c, 2 * n);
-
- for (i = t - 2; i >= 0; i--)
- {
- /* determine precision needed */
- bits = n * GMP_NUMB_BITS - mpn_scan1 (a, 0);
- n1 = (n * GMP_NUMB_BITS - bits) / GMP_NUMB_BITS;
-
- /* square of A : {c+2n1, 2(n-n1)} = {a+n1, n-n1}^2 */
- /* TODO: we should use a short square here, but this needs to redo
- the error analysis */
- mpn_sqr (c + 2 * n1, a + n1, n - n1);
-
- /* set {c+n, 2n1-n} to 0 : {c, n} = {a, n}^2*K^n */
-
- /* check overflow on f */
- if (MPFR_UNLIKELY (f < MPFR_EXP_MIN / 2 || f > MPFR_EXP_MAX / 2))
- {
- overflow:
- MPFR_TMP_FREE(marker);
- return -2;
- }
- /* FIXME: Could f = 2 * f + n * GMP_NUMB_BITS be used? */
- f = 2 * f;
- MPFR_SADD_OVERFLOW (f, f, n * GMP_NUMB_BITS,
- mpfr_exp_t, mpfr_uexp_t,
- MPFR_EXP_MIN, MPFR_EXP_MAX,
- goto overflow, goto overflow);
- if (MPFR_LIMB_MSB (c[2*n - 1]) == 0)
- {
- /* shift A by one bit to the left */
- mpn_lshift (a, c + n, n, 1);
- a[0] |= mpn_lshift (c + n - 1, c + n - 1, 1, 1);
- f --;
- if (error != t)
- err_s_a2 ++;
- }
- else
- MPN_COPY (a, c + n, n);
-
- if (error == t && 2 * n1 <= n &&
- mpn_scan1 (c + 2 * n1, 0) < (n - 2 * n1) * GMP_NUMB_BITS)
- error = i;
-
- if ((e >> i) & 1)
- {
- /* multiply A by B */
- c[2 * n - 1] = mpn_mul_1 (c + n - 1, a, n, B);
- f += h + GMP_NUMB_BITS;
- if ((c[2 * n - 1] & MPFR_LIMB_HIGHBIT) == 0)
- { /* shift A by one bit to the left */
- mpn_lshift (a, c + n, n, 1);
- a[0] |= mpn_lshift (c + n - 1, c + n - 1, 1, 1);
- f --;
- }
- else
- {
- MPN_COPY (a, c + n, n);
- if (error != t)
- err_s_ab ++;
- }
- if (error == t && c[n - 1] != 0)
- error = i;
- }
- }
-
- MPFR_ASSERTD (error >= 0);
- MPFR_ASSERTD (err_s_a2 >= 0);
- MPFR_ASSERTD (err_s_ab >= 0);
-
- MPFR_TMP_FREE(marker);
-
- *exp_r = f;
-
- if (error == t)
- return -1; /* result is exact */
- else /* error <= t-2 <= bitsize(mpfr_exp_t)-2
- err_s_ab, err_s_a2 <= t-1 */
- {
- /* if there are p loops after the first inexact result, with
- j shifts in a^2 and l shifts in a*b, then the final error is
- at most 2^(p+ceil((j+1)/2)+l+1)*ulp(res).
- This is bounded by 2^(5/2*t-1/2) where t is the number of bits of e.
- */
- return error + err_s_ab + err_s_a2 / 2 + 3; /* <= 5t/2-1/2 */
- }
-}