Intel Core i7 AVX GCC Compiler Tuning Results
When carrying out the recent Intel Sandy Bridge Shapes Up On GCC 4.7 Compiler benchmarks I conducted a few extra tests, which I had meant to put out earlier, but now with GCC 4.7 being released yesterday, it's a good time to go through these compiler optimizations on this 25th-anniversary GNU Compiler Collection release.
This testing was being done from the speedy Intel Core i7 3960X Sandy Bridge Extreme Edition system. The Core i7 3960X Sandy-E has six physical cores plus Hyper Threading and for this testing was overclocked to 4.5GHz. This system is a joy to work with -- especially for compiler testing -- since it can build the Linux kernel in under one minute. Ubuntu 12.04 LTS x86_64 with the Linux 3.2 kernel was running on the software side while built from source was the GCC 4.7 snapshot with --enable-lto and --enable-checking=release flags.
`core2'With the forthcoming Intel Ivy Bridge processors there is also the core-avx-i option that includes the Sandy Bridge (corei7-avx) options while also tacking in support for the new Ivy instruction sets: FSGSBASE, RDRND and F16C.
Intel Core 2 CPU with 64-bit extensions, MMX, SSE, SSE2, SSE3 and SSSE3 instruction set support.
Intel Core i7 CPU with 64-bit extensions, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1 and SSE4.2 instruction set support.
Intel Core i7 CPU with 64-bit extensions, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, AVX, AES and PCLMUL instruction set support.
Another option for Intel Sandy Bridge owners is to build out GCC with the --with-fpmath=avx configure switch. This option enables the GCC compilers to utilize AVX floating-point arithmetic.
Stay tuned for upcoming benchmarks of GCC 4.7 and LLVM/Clang 3.1. Those running their own compiler tests with the Phoronix Test Suite there are compiler reporting improvements if using 3.8-Bygland or newer.