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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /lib/int_sqrt.c | |
download | lwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz lwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'lib/int_sqrt.c')
-rw-r--r-- | lib/int_sqrt.c | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/lib/int_sqrt.c b/lib/int_sqrt.c new file mode 100644 index 000000000000..a5d2cdc5684c --- /dev/null +++ b/lib/int_sqrt.c @@ -0,0 +1,32 @@ + +#include <linux/kernel.h> +#include <linux/module.h> + +/** + * int_sqrt - rough approximation to sqrt + * @x: integer of which to calculate the sqrt + * + * A very rough approximation to the sqrt() function. + */ +unsigned long int_sqrt(unsigned long x) +{ + unsigned long op, res, one; + + op = x; + res = 0; + + one = 1 << 30; + while (one > op) + one >>= 2; + + while (one != 0) { + if (op >= res + one) { + op = op - (res + one); + res = res + 2 * one; + } + res /= 2; + one /= 4; + } + return res; +} +EXPORT_SYMBOL(int_sqrt); |