GCC & LLVM Clang Compiler Benchmarks On AMD's EPYC 7601
Smallpt is becoming quite quick on modern CPUs as a path tracer, but GCC 8.0 does give it an extra "oomph" of performance.
Meanwhile, LLVM Clang was slightly faster than GCC with the Stockfish chess benchmark.
GCC is faster than Clang when building the LAME MP3 encoder.
OpenSSL is one of the common workloads already tuned to death by all of the major compilers.