Following my most recent GCC 4.9 benchmarks for the open-source compiler that should be officially released next week, I ran some benchmarks of the GCC compiler results against LLVM's Clang 3.5 compiler in its latest SVN state. Here's the data for those curious how the very latest compiler code is comparing between GCC and LLVM/Clang.
The compiler benchmarking today is just a preview of more to come but is looking at the performance of the freshly-compiled GCC 4.8.2, GCC 4.9.0 RC1, and LLVM Clang 3.5 SVN compilers when compiling a variety of performance benchmarks. LLVM Clang 3.5 isn't expected for release until around the middle of the year so as that release approaches we will be back with more thorough (and time-consuming) benchmarks comparing LLVM Clang 3.5 against the 3.4 stable release, etc.
Benchmarking between GCC 4.8/4.9 and LLVM Clang 3.5 SVN was done from an Intel Core i7 4770K "Haswell" system running the Phoronix Test Suite for open-source test automation. For those curious about the initial performance figures of the 2014 GCC and LLVM/Clang compilers, continue on to the following pages.