[Mesa-dev] [PATCH 4/9] i965: remove unused members in blorp clear program

[Kenneth Graunke]

On 11/28/2013 11:44 PM, Kenneth Graunke wrote:
> On 11/27/2013 01:13 PM, Topi Pohjolainen wrote:
>> Documentation for R0 and R1 is taken from
>> fs_visitor::setup_payload_gen6().
>>
>> Signed-off-by: Topi Pohjolainen <topi.pohjolainen at intel.com>
>> ---
>>  src/mesa/drivers/dri/i965/brw_blorp_clear.cpp | 15 +++------------
>>  1 file changed, 3 insertions(+), 12 deletions(-)
>>
>> diff --git a/src/mesa/drivers/dri/i965/brw_blorp_clear.cpp b/src/mesa/drivers/dri/i965/brw_blorp_clear.cpp
>> index 2fa0b50..a937edb 100644
>> --- a/src/mesa/drivers/dri/i965/brw_blorp_clear.cpp
>> +++ b/src/mesa/drivers/dri/i965/brw_blorp_clear.cpp
>> @@ -104,12 +104,6 @@ private:
>>     const brw_blorp_const_color_prog_key *key;
>>     struct brw_compile func;
>>  
>> -   /* Thread dispatch header */
>> -   struct brw_reg R0;
>> -
>> -   /* Pixel X/Y coordinates (always in R1). */
>> -   struct brw_reg R1;
>> -
> 
> I like the fact that you're getting rid of these.  They're trivially
> reconstructable as brw_vec8_grf(0, 0) and brw_vec8_grf(1, 0), so storing
> them isn't really worthwhile.
> 
>>     /* Register with push constants (a single vec4) */
>>     struct brw_reg clear_rgba;
>>  
>> @@ -123,8 +117,6 @@ brw_blorp_const_color_program::brw_blorp_const_color_program(
>>     : mem_ctx(ralloc_context(NULL)),
>>       brw(brw),
>>       key(key),
>> -     R0(),
>> -     R1(),
>>       clear_rgba(),
>>       base_mrf(0)
>>  {
>> @@ -363,11 +355,8 @@ brw_blorp_const_color_params::get_wm_prog(struct brw_context *brw,
>>  void
>>  brw_blorp_const_color_program::alloc_regs()
>>  {
>> -   int reg = 0;
>> -   this->R0 = retype(brw_vec8_grf(reg++, 0), BRW_REGISTER_TYPE_UW);
>> -   this->R1 = retype(brw_vec8_grf(reg++, 0), BRW_REGISTER_TYPE_UW);
>> +   int reg = prog_data.first_curbe_grf;
> 
> This line doesn't make sense to me.  This function is what sets
> prog_data.first_curbe_grf.  Presumably you want:
> 
> /* Reserve space for g0 and g1, which contain the thread payload. */
> int reg = 2;
> 
> Otherwise, I think the line below will change clear_rgba to g0 rather
> than g2, which is probably not what you want.  Maybe I'm misreading.

Indeed, I can't read, sorry.  You changed it so that compile() sets
first_curbe_grf, and alloc_regs() uses it.  So your patch is correct.

Still, I think it would probably be nicer to keep it all contained in
alloc_regs().  It's such a tiny function though...

> 
>> -   prog_data.first_curbe_grf = reg;
>>     clear_rgba = retype(brw_vec4_grf(reg++, 0), BRW_REGISTER_TYPE_F);
>>     reg += BRW_BLORP_NUM_PUSH_CONST_REGS;
>>  
>> @@ -384,6 +373,8 @@ brw_blorp_const_color_program::compile(struct brw_context *brw,
>>     /* Set up prog_data */
>>     memset(&prog_data, 0, sizeof(prog_data));
>>     prog_data.persample_msaa_dispatch = false;
>> +   /* R0-1: masks, pixel X/Y coordinates. */
>> +   prog_data.first_curbe_grf = 2;
>>  
>>     alloc_regs();
>