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PCI phased out? (Announce)

posted by Rugxulo Homepage, Usono, 18.02.2011, 08:39

> > that was the point, you can't replace something when
> > it's heavily undocumented (though Win16 is worse here).
>
> .. afaik the DV/X function calls are in Ralph Brown. (IIRC 2F calls)
Knowing the interface is (intentionally) not the same as knowing the implementation. I assume you understand this. ;-) ;-)

> > You don't need extra registers (use push/pop).
>
> Slower since less pipelinable than non stalling reg operations. And the
> more regs, the more unnecessary stalls can be avoid.
Slower? Barely (if at all). Push/pop has been fast, esp. since Pentium (two in one clock). How many free registers is enough, 16? 256? 512? 1024?

> > You don't need to assume SSE2 (use CPUID),
>
> Double code generation unnecessary checks everywhere. And for what?
You only have to "check" (CPUID) once at startup and use function pointers loaded appropriately, then you don't have to worry about anything.

And like I said, the obvious advantages from using SSE2 are few and far in between, so the code duplication is very very little (way less than 1 kb for paq8o8z for literally a 2x speedup).

BTW, paq8o8 isn't Win64 (LLP64?) friendly, though it compiles for Linux64 fine. Fun fun fun.

> > which most compilers can't target anyways.
>
> FPC can, GCC, MSVC can, Intel can afaik. Borland has not 64-bit compilers.
I don't think so. Most of them pale heavily (from what I've heard) in comparison to Intel (no surprise). At least GCC, in my very limited testing, wasn't even 5% effective.

> > I've heard conflicting reports (Ross Ridge, Bart Oldemann), so I'm not
> > entirely sure if the cpu (long mode) itself or just the 64-bit OSes
> (Win64,
> > Linux64) refuse to support one or both of those.
>
> I've heard it repeated several times, not available in long mode. Afaik it
> is in the AMD manuals.
Unless you really want to dig in or ask these guys themselves, I suggest you keep an open mind. Not that I ever expect anybody to fix it or do anything about it, but I guess it's possible. In general, I would trust a kernel hacker more than an average joe. (And BTW, I read on Wikipedia yesterday that WINE 64-bit does run Win16 apps. It didn't say anything about slow emulation. But I haven't tested. Most, if not all, Win 3.x apps are indeed pmode-friendly.)

Like I said, I only know that DOSEMU x86-64 has to full emulate 16-bit real mode stuff, from personal testing. It's very slow for that, annoyingly slow (so 64-bit's own alleged speedups overall doesn't cover that wound). However, DJGPP (32-bit) stuff is native speed (e.g. Quake). I never tested any 16-bit pmode stuff since that's relatively rare these days (oddly). I should test again one day soon just for curiosity (HXDEV16 ftw!).

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