[clang] [llvm] Revert "CodeGen: Add LibcallLoweringInfo analysis pass (#168622)" (PR #171452)

[Aiden Grossman via cfe-commits]

boomanaiden154 wrote:

> Yep, we see that memcpy intrinsics started to be expanded into loops

Are you using a custom pass pipeline? You will need something like https://github.com/halide/Halide/pull/8892 or all of the libcalls will be marked as unsupported. If you have a custom target you might need to update `RuntimeLibcalls.td` so that memcpy and friends are enabled.

If this is with upstream clang/flang, this would be more concerning, but it does not seem like there are any regressions there. There are a decent amount of memory libcall lowering tests.

https://github.com/llvm/llvm-project/pull/171452