FPU support in EmuTOS (was:Re: [hatari-devel] Hatari WinUAE vs oldUAE information, and MiNT with MMU?)

["Roger Burrows" <anodyne@xxxxxxxxxxxx>]

On 14 Jan 2021 at 11:38, Christian Zietz wrote:

> Nicolas Pomarède schrieb:
>
> > As emutos supports 68060, maybe they could add such fpu soft emulation
> > in emutos too ?
>
> The Motorola Floating Point Support Package (FPSP) is quite large in
> size, over 50 kB compiled, even without the required OS hooks:
> https://github.com/torvalds/linux/blob/master/arch/m68k/ifpsp060/fpsp.sa
>
> Since EmuTOS is always limited by ROM space (even in the 512k versions),
> personally, I don't see that we would include FPU emulation for the
> 68060 into EmuTOS. I'd rather suggest making an AUTO folder program out
> of the FPSP, if that doesn't already exist.
>
I agree.

>
> PS: The one instruction that EmuTOS does emulate on the 68060 is MOVEP.
> I presume that is because afaik it's used in PureC startup code and,
> therefore, in many applications.

Indeed.  IIRC the CT60-specific ACCs and/or CPXs require it (because they are
written in PureC), so adding MOVEP support was really necessary.

Roger