[clang] [lld] [llvm] Run ObjCContractPass in Distributed Thin-LTO Pipeline (PR #92331)

[Nuri Amari via llvm-commits]

NuriAmari wrote:

> it seems like this should just be in the default codegen pipeline? you'd need to change the pass to bail out early if there are no relevant intrinsics (by checking if the module contains the intrinsic declaration) to not affect compile times

I've done this, and removed the other places the pass is added currently. Let me know if the location I've added it looks reasonable. Thanks.

> Maybe that is a good idea since the check is already there and the check is quite cheap (just check the existence of ARC intrinsics).

@cachemeifyoucan I couldn't find this check you're alluding to, so I added my own. If the check does exist, could you point me to it? If not, does mine look reasonable? Thanks.

https://github.com/llvm/llvm-project/pull/92331