[PATCH] D26348: Allow convergent attribute for function arguments

[Mehdi AMINI via Phabricator via llvm-commits]

mehdi_amini added a comment.

> //Example 1: Safe to fold.
>  void foo(int v, bool cond) {
> 
>   if (cond) {
>     // token1 = statepoint()
>     // bar(v, token1); // v needs to be convergent
>   } else {
>     // token2 = statepoint()
>     // bar(v, token2);  // v needs to be convergent
>   }
>   token_merged = statepoint()
>   bar(v, token_merged); // v needs to be convergent
> 
> }

My understanding was that this is *not* OK to fold, we don't know that two different "thread" have the same value for v. Can you elaborate, it is very possible that I'm misunderstanding something here.


https://reviews.llvm.org/D26348