[Bug rtl-optimization/66087] Invalid narrowing of MEM with containing POST_INC

[law at redhat dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66087

--- Comment #5 from Jeffrey A. Law <law at redhat dot com> ---
Interestingly enough it fails in a similar manner with LRA, but I agree that
avoiding this earlier in the pipeline is preferable.