[llvm] [loop-idiom] Forget outer loop scev when loop-idiom introduces memset… (PR #150916)

[Sushant Gokhale via llvm-commits]

sushgokh wrote:

> This looks OK to me, but I'd like to have a second opinion on only counting inaccessible memory as a side effect (for forward progress) here.

is there any criteria that what should be considered as side effect for a specific instruction? e.g. memset here can modify globals and hence, I am curious to know if even this should be considered as side effect

https://github.com/llvm/llvm-project/pull/150916