[llvm] [LoadStoreVectorizer] Support vectorization of mixed-type contiguous accesses (PR #177908)

[Anshil Gandhi via llvm-commits]

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gandhi56 wrote:

It seems that cmc-rep's solution will do. Precise knowledge of what the vector element type is helpful in `splitChainByContiguity` and `splitChainByAlignment`. So I implemented it.

https://github.com/llvm/llvm-project/pull/177908