[libc] [llvm] [APFloat] Add exp function for APFloat::IEEESsingle using expf implementation from LLVM libc. (PR #143959)

[Nikita Popov via llvm-commits]

https://github.com/nikic approved this pull request.

LGTM, let's give it a try.

https://github.com/llvm/llvm-project/pull/143959