[Mesa-dev] [PATCH] glsl: Small optimization for constant conditionals

[Iago Toral]

Hi Kenneth,

El 2014-04-17 08:57, Kenneth Graunke escribió:
> On 04/15/2014 03:30 AM, Iago Toral Quiroga wrote:
>> Once the relevant branch has been identified do not iterate over the
>> instructions in the branch, do a linked list insertion instead to 
>> avoid the
>> loop.
>> ---
>>  src/glsl/opt_if_simplification.cpp | 10 ++--------
>>  1 file changed, 2 insertions(+), 8 deletions(-)
> 
> Oh, this is nicer.
> 
> Reviewed-by: Kenneth Graunke <kenneth at whitecape.org>
> 
> and pushed.
> 
> By the way, usually people send cover letters for patches when there's 
> a
> large series, but not for a single patch.  If you have extra commentary
> about a patch, you can put that here, below the "---" and the diffstat.
>  (Anything below the "---" won't be part of the commit message when
> applied with "git am".)

Thanks for the review and for the tip! I will do this next time.

>> diff --git a/src/glsl/opt_if_simplification.cpp 
>> b/src/glsl/opt_if_simplification.cpp
>> index 2bec825..e05f031 100644
>> --- a/src/glsl/opt_if_simplification.cpp
>> +++ b/src/glsl/opt_if_simplification.cpp
>> @@ -90,15 +90,9 @@ ir_if_simplification_visitor::visit_leave(ir_if 
>> *ir)
>>         * that matters out.
>>         */
>>        if (condition_constant->value.b[0]) {
>> -	 foreach_list_safe(n, &ir->then_instructions) {
>> -	    ir_instruction *then_ir = (ir_instruction *) n;
>> -	    ir->insert_before(then_ir);
>> -	 }
>> +         ir->insert_before(&ir->then_instructions);
>>        } else {
>> -	 foreach_list_safe(n, &ir->else_instructions) {
>> -	    ir_instruction *else_ir = (ir_instruction *) n;
>> -	    ir->insert_before(else_ir);
>> -	 }
>> +         ir->insert_before(&ir->else_instructions);
>>        }
>>        ir->remove();
>>        this->made_progress = true;
>>