[Bug tree-optimization/68654] [6 Regression] CoreMark Pro performance degradation

[law at redhat dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68654

--- Comment #10 from Jeffrey A. Law <law at redhat dot com> ---
I've just scanned the provided dumps.  This is almost certainly a difference in
the SSA_NAME_VERSIONs causing different coalescing.  The tell-tale sign is
seeing identical code in the .optimized dump, except that the SSA_NAME versions
are different, then seeing different code being generated in the .expand dump.

This can be confirmed by providing the same dumps, but with the "details"
modifier.  ie, -fdump-tree-optimized-details