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Diffstat (limited to 'Build/source/libs/mpfr/mpfr-src/src/isqrt.c')
-rw-r--r-- | Build/source/libs/mpfr/mpfr-src/src/isqrt.c | 84 |
1 files changed, 0 insertions, 84 deletions
diff --git a/Build/source/libs/mpfr/mpfr-src/src/isqrt.c b/Build/source/libs/mpfr/mpfr-src/src/isqrt.c deleted file mode 100644 index f3d827eff47..00000000000 --- a/Build/source/libs/mpfr/mpfr-src/src/isqrt.c +++ /dev/null @@ -1,84 +0,0 @@ -/* __gmpfr_isqrt && __gmpfr_cuberoot -- Integer square root and cube root - -Copyright 2004-2020 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" - -/* returns floor(sqrt(n)) */ -unsigned long -__gmpfr_isqrt (unsigned long n) -{ - unsigned long i, s; - - /* First find an approximation to floor(sqrt(n)) of the form 2^k. */ - i = n; - s = 1; - while (i >= 2) - { - i >>= 2; - s <<= 1; - } - - do - { - s = (s + n / s) / 2; - } - while (!(s*s <= n && (s*s > s*(s+2) || n <= s*(s+2)))); - /* Short explanation: As mathematically s*(s+2) < 2*ULONG_MAX, - the condition s*s > s*(s+2) is evaluated as true when s*(s+2) - "overflows" but not s*s. This implies that mathematically, one - has s*s <= n <= s*(s+2). If s*s "overflows", this means that n - is "large" and the inequality n <= s*(s+2) cannot be satisfied. */ - return s; -} - -/* returns floor(n^(1/3)) */ -unsigned long -__gmpfr_cuberoot (unsigned long n) -{ - unsigned long i, s; - - /* First find an approximation to floor(cbrt(n)) of the form 2^k. */ - i = n; - s = 1; - while (i >= 4) - { - i >>= 3; - s <<= 1; - } - - /* Improve the approximation (this is necessary if n is large, so that - mathematically (s+1)*(s+1)*(s+1) isn't much larger than ULONG_MAX). */ - if (n >= 256) - { - s = (2 * s + n / (s * s)) / 3; - s = (2 * s + n / (s * s)) / 3; - s = (2 * s + n / (s * s)) / 3; - } - - do - { - s = (2 * s + n / (s * s)) / 3; - } - while (!(s*s*s <= n && (s*s*s > (s+1)*(s+1)*(s+1) || - n < (s+1)*(s+1)*(s+1)))); - return s; -} |