When running the Dhrystone 2 test within the BYTE Unix Benchmark, LLVM-GCC 4.2.1 came out on top while PCC, the Portable C Compiler, was the slowest and just in front of that was Open64. GCC 4.4.5 was the fastest on this Intel Atom 330 netbook and there was a small performance regression measured in GCC 4.5.1. Using the LLVM DragonEgg plug-in on GCC 4.5.1 also caused another performance drop.
The register arithmetic test in BYTE failed on the newer GCC compiler releases, just like in our other compiler testing articles, but between GCC 4.4.5, Open64, and PCC 0.9.9 20110126 there wasn't too much to look at.
While the register arithmetic results were virtually indifferent between the three working open-source compilers, when looking at BYTE's floating-point arithmetic performance the Open64 compiler had come out well ahead of GCC 4.4.5 and the Portable C Compiler.