Re: Lunia Update and 64-bit Instruction Size Advice Request

[Paige DePol <lual@...>]

KHMan <keinhong@gmail.com> wrote:

> On 5/31/2015 8:12 AM, Paige DePol wrote:
>> Roberto Ierusalimschy wrote:
>>> [snip]
>> [snip]
>> What sort of performance gains did you see from switching to the BCA
>> format, and which CPUs specifically had this issue, by the way?
> 
> 8086 thru 80286 and at least 68000. 80386 or later have barrel shifters for single cycle shifts. Old 8-bit microcontrollers often shift by 1 bit per instruction. But anything 32/64-bit that is a modern arch would have plenty of silicon on 130nm (or better) fabs and should do N bits at a time.
> 
> -- 
> Cheers,
> Kein-Hong Man (esq.)
> Kuala Lumpur, Malaysia

Well, I do not think I will be running Lunia on an 8086 or 80286! ;)

My targets will primarily be x64 architecture (for OSX) and ARM (for iOS), so I shouldn't be having too many issues. I like the new way I've laid out my Instruction format, it has all the important stuff right at the start, which as Roberto said, can't hurt... though really it probably wouldn't of mattered too much it seems!

Thanks for the information KHMan! Also, I would like to take this opportunity to thank you as well for your really informative "no frills guide" to the Lua VM! That PDF really helped get me going on understanding some of the inner workings of the Lua VM! :)

~Paige