------- Comment #7 from lucier at math dot purdue dot edu 2009-04-27 15:35 ------- Subject: Re: 96% performance regression in floating point code; part of the problem started 2009/03/12-13
On Mon, 2009-04-27 at 15:32 +0000, lucier at math dot purdue dot edu wrote: > On Mon, 2009-04-27 at 15:26 +0000, pinskia at gcc dot gnu dot org wrote: > > > This is by design -O1 is way slower than -O2 now. > > I have seen no general discussion that -O1 should be destroyed as a > useful compilation option. Perhaps I should also point out that code generated by -O2 is not generally much faster than before, so if you believe that -O1 is much slower than -O2 now by design, it is only by making code generated by -O1 much slower. BTW, this code runs in 108 ms when compiled with gcc-4.2.4 with the given options (including -O1). Brad -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39914
