On 4/23/2015 10:25 AM, Marc Glisse wrote: > On Thu, 23 Apr 2015, Tim Prince wrote: > >> From the looks of gcc 6.0, it appears that gnu_parallel STL is slated to >> become part of the release. > > Could you be more specific about what you are talking about and where > you got your information? I set -D_GLIBCXX_PARALLEL in previous versions but nothing happened. Now in 6.0 it goes parallel, but with poor performance. > > Parallel mode has been a part of libstdc++ for several years: > https://gcc.gnu.org/onlinedocs/libstdc++/manual/parallel_mode.html > >> Am I right in believing that gnu_parallel STL code is not simd >> vectorized? > > It is not manually vectorized, but the compiler is free to do it if it > can. Does this require setting -march and/or -ftree-vectorize options for libstdc++ build? What would be the recommended incantation? Thanks, -- Tim Prince
