Switching (back) to MSVC (Re: [Vm-dev] What generates disabledPlugins.c?0

[Juan Vuletich]

Andreas Raab wrote:
>
> On 7/22/2010 9:00 AM, Juan Vuletich wrote:
>> I heard that the MS tools can't reasonably be used with less than 2Gb of
>> ram and a fast processor. I've been regularly using the Win VM building
>> setup suggested by you for years on a P3 with 1Gb of memory. And my
>> current Win environment is a 1Gb VirtualBox inside a 2.5Gb Mac. I know,
>> I could dual boot to Win, to have the full 2.5Gb for it...
>
> That's the tools. You don't need to use much of the tools if you only 
> want to recompile (in fact, hopefully none). In other words, even if 
> this is true you should be no worse off than today.

Great!

>> Besides, Cog does not generate native code for every CompiledMethod in
>> the system, so I wonder if there would be a visible performance loss
>> leaving GCC.
>
> That remains to be seen, but I don't think this is going to be an 
> issue. The performance differences have been historically high in 
> micro benchmarks (2x) but much less pointed in macro benchmarks (10%). 
> In fact, when measuring performance without the core interpreter loop 
> (i.e., just the primitives) the MS compiler historically fared better 
> than GCC (noticable for example for complex BitBlt rules). The big 
> gain of GCC was static register assignments for interpret() which has 
> been severely broken in GCC 3 and 4 (which is the reason I'm sticking 
> with 2.95.2). And since the core interpreter loop is precisely what 
> Cog optimizes I would actually expect a net benefit but we'll have to 
> run the benchmarks to be sure.
>
> Cheers,
>   - Andreas

I see. So maybe this even brings an actual performance improvement!
Thanks for your answer, and for your constant and continued effort on 
the Windows VM.

Cheers,
Juan Vuletich