[clang] [llvm] [SROA] Canonicalize homogeneous structs to fixed vectors (opt-in, after memcpyopt) (PR #165159)

[Matt Arsenault via llvm-commits]

================

----------------
arsenm wrote:

Should a variant of this be added to test/PhaseOrdering to test the pass pipeline config change? 

https://github.com/llvm/llvm-project/pull/165159