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varobert@xxxxxxxxxx writes:
> I can't test it on video bitmaps because for some reason screen->seg is
> invalid.
Unlikely, as nothing would work at all if that was the case. More likely is
that your MMX code just doesn't handle farptr access correctly.
> or you can't use MMX's movq on video memory.
I don't know enough about MMX to answer that one, sorry.
> Question: does WRITE_BANK() reset the FPU in any way ?
Maybe: that depends on what happens inside whatever driver functions we
call. You certainly can't rely on VESA calls and DirectX surface locking not
use the FPU for something, so you'd better assume a total clobber.
> Apart for VESA1 and 2B, do we really need to call this ?
Very much so. The bank switchers are used for many things, including bank
switching on drivers that need that, and various housekeeping tasks on other
systems.
--
Shawn Hargreaves - shawn@xxxxxxxxxx - http://www.talula.demon.co.uk/
"A binary is barely software: it's more like hardware on a floppy disk."