They both do, yes. LLVM's [1] includes (some of?) gcc's, the reverse may also be true. LLVM also has extensive unit tests that can exercise codegen and backen

They both do, yes. LLVM's [1] includes (some of?) gcc's, the reverse may also be true. LLVM also has extensive unit tests that can exercise codegen and backend functionality. [1] https://github.com/llvm/llvm-test-suite https://github.com/llvm/llvm-test-suite