[clang] [llvm] Global string alignment (PR #142346)

[Eli Friedman via llvm-commits]

https://github.com/efriedma-quic commented:

I'm a little concerned we don't want to play whack-a-mole with this... but I guess optimizations generally won't explicitly request an alignment of "1", so this is probably good enough?

Please write a test specifically for instcombine, not a clang test.

https://github.com/llvm/llvm-project/pull/142346