[llvm] [CodeGen] Preserve branch weights from PGO profile during instruction selection at -O0 (PR #161620)

[Nikita Popov via llvm-commits]

nikic wrote:

> ... to the pipeline. Do these analyses not affect compile time?

They do: https://llvm-compile-time-tracker.com/compare.php?from=8a0d145d90df3eefd5e54a2b04d4f4f2515e99cc&to=3c131e564623813f71bb76011be3e812c5a65a7d&stat=instructions:u

https://github.com/llvm/llvm-project/pull/161620