[clang] [llvm] [SROA] Vector promote some memsets (PR #133301)

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macurtis-amd wrote:

Thanks Nikita for taking a look at this.

> Missing PR description. 

I've updated the PR description.

> The tests also don't make any sense to me, seeing as they compile down to a constant, unused insertelement.

Yes. Tests are very synthetic. Reduced from the already reduced [example](https://godbolt.org/z/8ebcTEjTs) given in the PR description. I'll see if I can produce something of about the same size but more practical.

Do you think it would make sense to add that example as a test case?

https://github.com/llvm/llvm-project/pull/133301