On 1/12/07, H. J. Lu <[EMAIL PROTECTED]> wrote:
On Thu, Jan 11, 2007 at 08:06:31PM -0500, Daniel Berlin wrote:
> On 1/11/07, Grigory Zagorodnev <[EMAIL PROTECTED]> 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.
I'm happy to backport it, but it's going to introduce other possible
problems in 4.2.
H.J.
