[llvm] [GVN] Allow loop-load PRE when the blocker is in an inner loop (PR #227983)

[via llvm-commits]

anupkum-sgs wrote:

> This is mixing multiple changes. The use of willNotFreeBetween() can be landed separately, and raising the limit on the walk needs to be evaluated independently -- this looks like an inappropriately high limit for an ad-hoc query.

In most of the cases I found that the inner-loop blocker is due to an
aliasing issue, and in such an aliasing scenario canBeFreed returns true
(which I mentioned in my RFC), so even if we allow the inner-loop blocker
without willNotFreeBetween it would be meaningless.

So I think we can do the following:
1) first PR for the use of willNotFreeBetween
2) then to allow the inner-loop blocker

Shall I proceed with this?


https://github.com/llvm/llvm-project/pull/227983