[llvm] [JumpThreading] Copy metadata when inserting preload into preds (PR #134403)

[Nikita Popov via llvm-commits]

https://github.com/nikic commented:

It looks like the compile-time impact is unchanged, so it's actually coming from the JumpThreading changes.

I wonder whether this is due to second order effects. E.g. Halignmm.c.o has a 6% compile-time increase on aarch64, but also a 0.8% code size decrease.

https://github.com/llvm/llvm-project/pull/134403