i^=i

Not usually. I think you got this from the old asm trick that "xor ax, ax" was more efficient than "mov ax, 0". That was simply because the code size for the former was less than the latter.

I was curious, because for people who don''t have asm experience (read: me), i^=i took some time to figure out. i = 0 seemed a little more straightforward. Anyway, thanks.

diddly

If you have a post Stone-Age compiler,
it will already optimize i=0 into i^=i;

Of course, on µPs with a zero register,
loading from that register is as fast,
and doesn''t hog the ALU.

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i^=i requires a read and write, and if i is a variable that is actually stored in memory I suspect that mov will be faster, since it''s just a write. For registers, i^=i should be faster but compilers should optimize it anyway.