Re: bitwise operations in obj C
Re: bitwise operations in obj C
- Subject: Re: bitwise operations in obj C
- From: John Stiles <email@hidden>
- Date: Wed, 17 Oct 2007 10:58:57 -0700
Don't guess. Use Shark and find out what actually takes time. I
suspect you'll be in for some fun surprises.
On Oct 17, 2007, at 10:40 AM, Erfan Aleemullah wrote:
well, not exactly sure, but the program is nearing beta release,
and i'm
trying to eliminate leaks and increase efficiency. So, not exactly
sure if
i *absolutely need to do bit ops here, but it would definitely
help, because
the operation is done everytime the linenumbers increment
themselves - so
when the line number is 100,000, the code would have 'modulo'ed'
100,000
times and as the numbers get large themselves--> eg) 100,000 % 12 =
slightly
expensive yes?
On 10/17/07, Clark Cox <email@hidden> wrote:
On 10/17/07, Erfan Aleemullah <email@hidden> wrote:
hello all,
I have a modulus operation in my code and it runs fine, but my
original
algorithm avoided division all together for speed reasons - I am
using
modulus due to a change in requirements.
How exactly (or can I) use bit operations to achieve the same
effect and
increase my speed here ?
Are you sure that integer division is actually your bottleneck here?
Have you profiled you code?
Code:
line_Number++;
if(line_Number % increment == 0)
// lineNumber is any
integer
value > 0, can get large w/ time - 100,000++
{ // increment is user
selectable
integer from a set of given values
....
....
}
--
Clark S. Cox III
email@hidden
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