[Bug tree-optimization/121474] [16 Regression] investigate only having alias walk in forwprop1 or at -O2+

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121474

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|---                         |FIXED

--- Comment #6 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
I think this is fully fixed.
-O1 does not do the walk.
-O2 only does the walk for forwprop1/2.

Clobbers are not counted towards the walk if they are at the end of the walk.
This allows -O1 and forwprop3/4 to skip over clobbers and provide the decent
code generation while still having clobbers there.