GCC vs. Clang Compiler Benchmarks On POWER9 With Raptor's Blackbird

While for Intel x86_64 with the latest compilers it's a very competitive race between LLVM Clang and GCC, how is that battle playing out on the IBM POWER9 front? Using the interesting Raptor Blackbird with IBM POWER9 4-core / 16-thread CPU, here are some recent benchmarks I did between GCC 9, GCC 10, and LLVM Clang 8.