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Date: Thu, 24 Feb 2011 12:21:13 +0100
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From: Laurent Desnogues <laurent.desnogues@gmail.com>
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Subject: [Qemu-devel] Re: QEMU regression problems - Update FPU
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Maydell <peter.maydell@linaro.org>, Roy Tam <roytam@gmail.com>, seabios@seabios.org, qemu-devel@nongnu.org, Kevin O'Connor <kevin@koconnor.net>, Gerhard Wiesinger <lists@wiesinger.com>, Aurelien Jarno <aurelien@aurel32.net>

On Thu, Feb 24, 2011 at 12:10 PM, Paolo Bonzini <pbonzini@redhat.com> wrote=
:
> On 02/23/2011 08:04 PM, Aurelien Jarno wrote:
>>
>> Actually that's the reason why i386 doesn't use softfloat, as all the
>> trigonometric use libm, and the bridge between softfloat and libm is not
>> working correctly (plenty of type abuse).
>
> Besides, I doubt softfloat would want bug-compatible trig function
> implementations. =A0fsincos for example is a far cry from the precision o=
f the
> libm function.

I agree, these functions certainly don't belong to SoftFloat.
They should be implemented in target-i386/op_helper.c.  But
bit accuracy might be difficult to achieve, unless Intel/AMD
properly documented how they compute all these functions.


Laurent