[Mesa-dev] softpipe GL3 status

[Bryan Cain]

On 01/06/2012 01:26 PM, Ian Romanick wrote:
> On 01/06/2012 09:04 AM, Dave Airlie wrote:
>> Hi guys,
>>
>> Just a quick note, I've just spent a week or so trying to see where
>> gallium and softpipe were w.r.t GL3.0 support.
>>
>> I've pushed a branch to my repo called softpipe-gl3. It contains
>> patches in various state of usefulness but it brings the piglit
>> results to 220 failures in 7623 tests, which isn't bad.
>>
>> Outstanding known problems (stuff I've dug into).
>>
>> smooth interpolation is broken in softpipe, worth about 70-100 fixes
>> at a quick guess.
>>
>> integer abs - we have no TGSI representation for this, should we lower
>> it to something?
>
> Or just generate some TGSI instructions to implement it.  You should
> be able to fake it with a CMP-like instruction.  I think that's how
> i915 does it in hardware.

Depends on whether there's any hardware with a native integer abs
instruciton.  If there is, we should just add a new IABS instruction to
TGSI and let drivers implement it how they want.  Otherwise, your
suggestion should work.

>
>> integer SSG (set sign) - no TGSI for this, lower it?
>
> Where is SSG being generated?  I thought ir_to_mesa was the only thing
> that generated it, and Gallium shouldn't hit that path.

glsl_to_tgsi still generates the TGSI equivalent; that part hasn't been
changed from ir_to_mesa.

Bryan