Re: [Qemu-devel] [PATCH v2 1/5] target-tricore: Added FTOUZ instruction

[Bastian Koppelmann]

On 11/08/2016 04:06 PM, Richard Henderson wrote:
> On 11/08/2016 02:37 PM, Bastian Koppelmann wrote:
>> Consider 0x836d4e86 as an input which is clearly negative, however
>> float_flag_invalid is not set. The hardware on the other hand does set
>> it.
> 
> Hmm.  This is -0x1.da9d0cp-121.  Softfloat claims that we should round
> to zero first, and only if the result is still < 0, raise invalid. 
> Which does sound plausible as a common behaviour.

TriCore does it the other way round.

> 
> Does your hardware raise invalid for true -0.0, i.e. 0x80000000?

No, -0.0 does not raise invalid.

Cheers,
    Bastian