On Thu, Jan 11, 2007 at 08:06:31PM -0500, Daniel Berlin wrote:
> On 1/11/07, Grigory Zagorodnev <grigory_zagorodnev@linux.intel.com> wrote:
> >Menezes, Evandro wrote:
> >> Though not as pronounced, definitely significant.
> >>
> >
> >Using binary search I've detected that 30% performance regression of
> >cpu2006/437.leslie3d benchmark is caused by revision 117891.
> >
> >http://gcc.gnu.org/viewcvs?view=rev&revision=117891
> >
> >I assume same commit causes regression of all other benchmarks from
> >cpu2k6 suite (running others to confirm).
>
> This only affects 4.2, and the only solution would be to try to
> backport some of the 4.3 aliasing stuff to 4.2, which i'm not sure is
> a great idea.
>
If this serious performance in gcc 4.2 isn't addressed, it may
make gcc 4.2 less attractive since it may generate much slower
executables.