[Mesa-dev] [PATCH] i965: Use SIMD16 math on Ivybridge.

[Kenneth Graunke]

On 09/26/2011 06:08 PM, Eric Anholt wrote:
> On Mon, 26 Sep 2011 16:51:34 -0700, Kenneth Graunke <kenneth at whitecape.org> wrote:
>> Signed-off-by: Kenneth Graunke <kenneth at whitecape.org>
>>
>> ---
>>  src/mesa/drivers/dri/i965/brw_fs_emit.cpp |   14 ++++++++++----
>>  1 files changed, 10 insertions(+), 4 deletions(-)
>>
>> diff --git a/src/mesa/drivers/dri/i965/brw_fs_emit.cpp b/src/mesa/drivers/dri/i965/brw_fs_emit.cpp
>> index 8176a76..b35d558 100644
>> --- a/src/mesa/drivers/dri/i965/brw_fs_emit.cpp
>> +++ b/src/mesa/drivers/dri/i965/brw_fs_emit.cpp
>> @@ -151,7 +151,10 @@ fs_visitor::generate_math1_gen6(fs_inst *inst,
>>  
>>     assert(inst->mlen == 0);
>>  
>> -   brw_set_compression_control(p, BRW_COMPRESSION_NONE);
>> +   bool force_simd8 = intel->gen < 7 || dst.type != BRW_REGISTER_TYPE_F;
>> +
>> +   if (force_simd8)
>> +      brw_set_compression_control(p, BRW_COMPRESSION_NONE);
> 
> I'm not following why force simd8 for dst.type != BRW_REGISTER_TYPE_F.

Ah, I neglected to add a comment about that.