[polly] scop detection: detect regions bottom up

[Tobias Grosser]

On 06/14/2013 12:44 PM, Sebastian Pop wrote:
> Tobias Grosser wrote:
>>> Here is a patch that makes scop detection to work bottom up.  On my huge C++
>>> benchmark, the attached patch gets the overall sequential time spent in Polly
>> >from 2151 seconds to 1573 seconds.
>>
>> Nice. How much of the compile time is that? Could you just run the
>> scop detection,
>> but disable scheduler and code generation. I would be interested
>> what percentage of compile time scop detection use in a release -O3
>> run.
>>
>
> $ grep 'Polly -' build.log.2013_06_12_12_17_13 | gawk '{ sum += $1 }; END { print sum }'
> 1573.23
> $ grep 'Polly - Detect static control parts' build.log.2013_06_12_12_17_13 | gawk '{ sum += $1 }; END { print sum }'
> 1441.97
>
> So the rest of Polly takes 131.26 seconds.  Before all my patches, the total
> sequential time spent in Polly was 15411.3 seconds.

I am still missing the overall compile-time to understand many percent 
of the compile-time is actually spent in Polly. If -O3 takes 10 seconds, 
scop detection is super slow. if -O3 takes 10^1000 seconds, scop 
detection is actually amazingly fast, but we just don't find anything to 
optimize.

Cheers,
Tobi