Re: [Qemu-devel] [Bug 645662] x87 fpu emulation not accurate enough

[Thomas Huth]

On 29.11.2017 16:20, KONRAD Frederic wrote:
> 
> 
> On 11/29/2017 01:51 PM, Peter Maydell wrote:
>> On 29 November 2017 at 12:47, KONRAD Frederic
>> <address@hidden> wrote:
>>> Maybe a little hack might work for x86 on x86 though.
>>> Something like hardcoding the helper with an inline assembly
>>> code?
>>
>> The set of people who want to emulate x86 on x86 is surely
>> even smaller than the already tiny set of people who want to
>> emulate x86 at all. I don't think it makes sense to add
>> inline assembly hacks for that: QEMU should (as far as
>> is reasonably possible) behave the same on all hosts.
>>
> 
> Sure it was a first step suggestion.

FYI, there is some code in WinUAE / Previous which might be usable, see
e.g. WinUAE sources here:

https://github.com/tonioni/WinUAE/blob/master/softfloat/softfloat_fpsp.cpp

But the code is targetted for m68k only so far, so it likely needs some
work, and we're currently discussing whether it's feasible to include it
into QEMU at all, see this thread here:

https://lists.gnu.org/archive/html/qemu-devel/2017-11/msg05342.html

 Thomas