[Bug debug/54402] [4.8 Regression] var-tracking does not scale

[ro at CeBiTec dot Uni-Bielefeld.DE]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54402

--- Comment #24 from ro at CeBiTec dot Uni-Bielefeld.DE <ro at CeBiTec dot Uni-Bielefeld.DE> 2012-12-13 13:12:00 UTC ---
> --- Comment #22 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-12-12
> 22:21:57 UTC ---
> Created attachment 28942
>   --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=28942
> --param max-vartrack-reverse-op-size patch
>
> Another patch, to avoid adding reverse ops to VALUEs that already have lots of
> locs, assuming for such locs it is unlikely going to be useful.
> With the default of 50 (+ the previous sparc hack) in x86_64 -> sparc-solaris
> cross the go1 testcase compiled in about 1.5 minutes, with 10 instead in 50
> seconds or so, with 100 in 3 minutes, etc.

I've now retested the full sparcv9 reflect libgo test with this patch
and the sparc hack:

real       24:03.27
user       24:02.70
sys            0.49

This is still way beyond the 5 min timeout (which isn't enforced for
libgo compilations), but way better than 11 hours.

With -fno-var-tracking-assignments, I get:

real        3:43.45
user        3:43.00
sys            0.33

Thanks.
    Rainer