GCC vs. LLVM Clang Is Mixed On The Ivy Bridge Extreme

The BLAKE2 cryptography performance is still much faster on GCC than with LLVM's Clang.

Botan's KASUMI performance was also noticeably faster with GCC 4.7.2 and GCC 4.8.1 over LLVM Clang 3.2 and LLVM Clang 3.3.

Botan's AES-256 performance was the fastest on GCC 4.7.2 but regressed with GCC 4.8.1, to a point where LLVM Clang 3.2/3.3 was now faster than the Free Software Foundation's compiler.

LLVM Clang secured some straight-up wins with CAST-256 performance in Botan.