[Bug tree-optimization/90316] [8/9 Regression] large compile time increase in opt / alias stmt walking for Go example

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90316

--- Comment #33 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Than McIntosh from comment #32)
> Compile time for the larger example looks good for the most recent commit on
> trunk (271124), ~130 seconds. Thanks for all your help on this.

Great!  Can you verify whether just this commit (r271124) applied ontop of
the GCC 9 branch has a similar result?  That's the most safe single commit
to backport (also to the GCC 8 branch where it applies as well, so bonus
if you can check there, too).