[Bug rtl-optimization/93565] [9/10 regression] Combine duplicates instructions

[segher at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93565

--- Comment #18 from Segher Boessenkool <segher at gcc dot gnu.org> ---
Created attachment 47841
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=47841&action=edit
Patch to treat sign_extend as is_just_move