Re: [hatari-devel] FPU rounding

[Nicolas Pomarède <npomarede@xxxxxxxxxxxx>]

Le 11/11/2014 00:02, Douglas Little a écrit :
> Quick update on this problem...
>
> Frank Wille (of VASM/VBCC fame) did a little investigating for me and
> apart from confirming the FP rounding problem in UAE, he discovered that
> several versions of UAE behave quite differently from each other with
> respect to rounding.
>
> It seems however that the most recent versions have fixed both FINT and
> FMOVE so they both now work correctly. I'm not sure if that includes
> WinUAE or just UAE but it sounds like the problem has at least been
> recognized and could make it into Hatari along with a new core at some
> point...

On different discussion, Toni Wilen from WinUAE also told me that latest 
WinUAE had several improvements in FPU :

"But there has been lots of recent FPU related changes too, for example 
optional softfloat library support (100% exact results but much slower), 
this is not fully implemented yet. Also 68040 weird missing FPU 
instruction exception stack frames are finally supported (=motorola fpsp 
library works, if for some reason there is need to emulate missing 
instructions as really missing) some things may have gotten broken too.. "

Well, we'll see what we get, but your current work on Quake 2 for falcon 
will certainly be useful to compare real HW to emulation and help 
improving the emulation part when it differs.

Nicolas