[llvm] [polly] [delinearize] Extract array dimensions from alloca and global declarations (PR #156342)

[Sebastian Pop via llvm-commits]

sebpop wrote:

Thank you for #161822, yes this is a good direction and it is orthogonal to the patch to reads the info from global and alloca types.  (By orthogonal I mean: we may recover enough info just from the shape of memory access functions without external help from the front-ends.)

> is this direction not sufficient for your needs?

I don't know yet: we will know if `delinearizeFixedSizeArray` is sufficient once we have a way to delinearize all the use-cases we have in the testsuite in DA + delinearize and in Polly.  The current implementation of `delinearizeFixedSizeArray` needs some more work to recover the info currently read from GEPs.

https://github.com/llvm/llvm-project/pull/156342