[clang] [llvm] [LV][LAA] Vectorize math lib calls with mem write-only attribute (PR #78432)

[Paschalis Mpeis via cfe-commits]

paschalis-mpeis wrote:

Rebased to main after a couple of weeks of inactivity.

Note: windows x64 build failure seems unrelated; more likely a wide problem, failing at cmake configure.

https://github.com/llvm/llvm-project/pull/78432