[llvm] [DA] Test AddRecs are nsw before strong SIV test (PR #183421)

[Ehsan Amiri via llvm-commits]

amehsan wrote:

> Actually, I am going to update this PR and move the nsw check back to `testSIV` function. Will update it soon.

never mind, let's merge this as is. 

https://github.com/llvm/llvm-project/pull/183421