[Mesa-dev] [PATCH] i965/fs: Change the type of booleans to UD and emit correct immediates

[Matt Turner]

On Tue, Oct 28, 2014 at 12:10 PM, Jason Ekstrand <jason at jlekstrand.net> wrote:
>
> On Oct 28, 2014 11:57 AM, "Matt Turner" <mattst88 at gmail.com> wrote:
>>
>> On Thu, Oct 16, 2014 at 3:40 PM, Jason Ekstrand <jason at jlekstrand.net>
>> wrote:
>> > Before, we used the a signed d-word for booleans and the immedates we
>> > emitted varried between signed and unsigned.  This commit changes the
>> > type
>> > to unsigned (I think that makes more sense) and makes immediates more
>> > consistent.  This allows copy propagation to work better cleans up some
>> > instructions.
>> >
>> > total instructions in shared programs: 5473519 -> 5465864 (-0.14%)
>> > instructions in affected programs:     432849 -> 425194 (-1.77%)
>> > GAINED:                                27
>> > LOST:                                  0
>>
>> I assumed at first that this was on Haswell, but it couldn't be
>> because Haswell doesn't use 0/1 for boolean. What platform was this?
>
> It doesn't matter what form of booleans the arch uses.  I believe it was on
> HSW.

It's unclear to me how you're coming to that conclusion. None of the
hunks in brw_fs_visitor.cpp affect platforms where
Const.UniformBooleanTrue != 1.

I suppose the meaningful change in this patch for those platforms is
the one in brw_shader.cpp.

> However, as I have mentioned in private, I've had trouble running
> shaderdb and believing the results.  They could be bogus but I don't think
> so.

Also unclear to me how you could not when I just tested it myself.