I normally compile my programs with the CFLAGS -O1 -pipe -march=native -ftree-vectorization. I assumed back when i used GCC version 5 that because skylake was not an march option yet it would not make full use of the SIMD instructions on Intel's Skylake generation processors. I added in the -ftree-vectorization parameter to make the resulting binaries check if certain SIMD extensions exist and use them. At least i thought that is what it did.
With GCC version 6.4 is the ftree parameter still necessary? Especially when -O2 is used. The only reason i used -O1 before was due to a bug in some software i was using at the time that has since been patched. Also on an unrelated note is the -mtune parameter redundant if you have already specified -march? _______________________________________________ PLUG mailing list [email protected] http://lists.pdxlinux.org/mailman/listinfo/plug
