[llvm-commits] BlockFrequency for BasicBlocks

[Jakub Staszak]

On Jun 22, 2011, at 6:57 PM, Andrew Trick wrote:

> On Jun 22, 2011, at 6:16 PM, Jakub Staszak wrote:
> 
>> Previously we used getEdgeFreq which is wrong, because sum of them for some BB from all its predecessors might be greater than START_FREQ.
> 
> The algorithm assumes that will never happen when BB is the loop head currently being processed. If it does happen (irreducible inner loops?) then I don't know how to calculate cyclic probability. I would just pick a reasonably high value.

The previous version of the patch used to do this. We divided by pretty small number, but I think we didn't like it, did we? I don't know which version you prefer, I think I like the current one.

- Kuba