diff options
Diffstat (limited to 'lib/int_sqrt.c')
-rw-r--r-- | lib/int_sqrt.c | 70 |
1 files changed, 0 insertions, 70 deletions
diff --git a/lib/int_sqrt.c b/lib/int_sqrt.c deleted file mode 100644 index 30e0f9770f88..000000000000 --- a/lib/int_sqrt.c +++ /dev/null @@ -1,70 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * Copyright (C) 2013 Davidlohr Bueso <davidlohr.bueso@hp.com> - * - * Based on the shift-and-subtract algorithm for computing integer - * square root from Guy L. Steele. - */ - -#include <linux/kernel.h> -#include <linux/export.h> -#include <linux/bitops.h> - -/** - * int_sqrt - computes the integer square root - * @x: integer of which to calculate the sqrt - * - * Computes: floor(sqrt(x)) - */ -unsigned long int_sqrt(unsigned long x) -{ - unsigned long b, m, y = 0; - - if (x <= 1) - return x; - - m = 1UL << (__fls(x) & ~1UL); - while (m != 0) { - b = y + m; - y >>= 1; - - if (x >= b) { - x -= b; - y += m; - } - m >>= 2; - } - - return y; -} -EXPORT_SYMBOL(int_sqrt); - -#if BITS_PER_LONG < 64 -/** - * int_sqrt64 - strongly typed int_sqrt function when minimum 64 bit input - * is expected. - * @x: 64bit integer of which to calculate the sqrt - */ -u32 int_sqrt64(u64 x) -{ - u64 b, m, y = 0; - - if (x <= ULONG_MAX) - return int_sqrt((unsigned long) x); - - m = 1ULL << ((fls64(x) - 1) & ~1ULL); - while (m != 0) { - b = y + m; - y >>= 1; - - if (x >= b) { - x -= b; - y += m; - } - m >>= 2; - } - - return y; -} -EXPORT_SYMBOL(int_sqrt64); -#endif |