[Bug tree-optimization/66610] Compound assignments prevent value-numbering optimization with unions

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66610

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |missed-optimization
            Summary|Compound assignments        |Compound assignments
                   |prevent value-numbering     |prevent value-numbering
                   |optimization                |optimization with unions

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
IIRC VN has some struct copy infrastructure which could be used here but unions
are special and that might the cause.