LLVM/Clang 3.2 Compiler Competing With GCC

With last week's release of LLVM 3.2, here are new benchmarks of LLVM 3.2 with the Clang C/C++ compiler front-end. The LLVM/Clang 3.2 performance using last week's source code releases were compared to the earlier LLVM/Clang 3.1 release and then for competition was the GCC 4.7.2 stable release and the latest GCC 4.8.0 development snapshot.

First of all, for those not familiar with the new capabilities introduced by LLVM/Clang 3.2, read What Features LLVM/Clang 3.2 Bring To The Table as it covers all of the major features introduced to this second LLVM release of 2012.

LLVM/Clang 3.1, LLVM/Clang 3.2, GCC 4.7.2, and GCC 4.8.0 20121223 were the candidates for testing using the official source packages and building them all under an Ubuntu 13.04 snapshot. All of the compilers were built in their release/optimized modes (for LLVM/Clang with no assertions and enabling the optimized mode while GCC had the release checking mode enabled). All of the testing from Ubuntu 13.04 with the Linux 3.7 kernel was done from an Intel Core i7 3770K "Ivy Bridge" CPU. The CFLAGS/CXXFLAGS were set to "-O3 -march=native" during the testing process.

Additional LLVM/Clang 3.2 benchmarks are forthcoming to look at different compiler tuning/switches and their impact on performance as well as analysis in other areas for this increasingly popular and useful compiler infrastructure. All benchmarking was handled via the Phoronix Test Suite.