[PATCH] [Polly] Extract number of elements/iterations for a isl_set/isl_ast_node

Tobias Grosser tobias at grosser.es
Fri Oct 10 03:45:31 PDT 2014

On 10.10.2014 12:39, Sven Verdoolaege wrote:
> On Fri, Oct 10, 2014 at 08:26:16AM +0200, Tobias Grosser wrote:
>> I am not sure. I was hoping we could just look at the schedule and will find
>> a simple computation, but thinking about it this morning for a little, I did
>> not really make progress.
> I don't see how you could derive this information from the schedule
> since you don't know in advance how the AST generator will split
> up the schedule.

We can get the split up schedule from isl_ast_build, but I am still 
afraid that we may not be able to derive from this a precise answer. 
Specifically, the AST generator may avoid the generation of certain 
conditions in the outer loops relying on the inner loop to filter them 
out, no?

>> I will CC Sven who may have an idea. (In fact it may even be that the isl
>> ast generator is the best place to compute such information as it could
>> possibly allow us to give a more precise answer).
> Probably, yes.

This was answering if the AST generator is the right place.

Do you happen to have an idea if/how to implement it there? Or are you 
possibly even thinking of looking into this yourself?


More information about the llvm-commits mailing list