GCC 5.3 Optimization Level Tests From -O0 To -Ofast
A new Phoronix Premium subscriber had inquired this morning about having more GCC optimization benchmarks. Besides Phoronix Premium getting you an ad-free experience and the ability to view multi-page articles on a single page while the funds go to ensure more content and Linux hardware tests, etc, on Phoronix, I always try my best to honor Phoronix Premium subscriber requests for tests and future articles. Thus I managed to find some time today to start running some fresh GCC optimization benchmarks.
In this first article are GCC tests with the new Intel Xeon E3 1245 v5 Skylake system while running Fedora 23 64-bit with its GCC 5.3.1 compiler. The CFLAGS/CXXFLAGS tested with a variety of open-source tests via the Phoronix Test Suite were -O0, -O1, -O2, -O3, -Ofast, and -Ofast -march=native. If you don't know what those compiler switches mean, see the GCC documentation.