Messages in this thread | | | Date | Mon, 11 Jun 2001 14:06:14 +0200 (CEST) | From | Maciej Zenczykowski <> | Subject | Re: Break 2.4 VM in five easy steps |
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On Fri, 8 Jun 2001, Pavel Machek wrote:
> That modulo is likely slower than dereference. > > > + if (count % 256 == 0) {
You are forgetting that this case should be converted to and 255 or a plain byte reference by any optimizing compiler - and gcc surely is, on x86 this code can be reduced to around 2 cycles (Pentium: mov, or, jnz, with preceding code intertwined to cancel stalls and jnz being likely in the code buffer)...
Maciek
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