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

[Alexey Bataev via cfe-commits]

alexey-bataev wrote:

Looks like this change increased size/runtime of the code at O0 with the debug info, we see lots of timeouts in the code compiled with `-O0 -g` options. Shall it be disabled at O0?
Debug info requires some extra code for the correct debug info and causes emission of extra spills/reloads

https://github.com/llvm/llvm-project/pull/168622