[Bug rtl-optimization/78952] Combine does not convert 8-bit sign-extract to a zero-extract for QImode operations

[segher at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78952

--- Comment #3 from Segher Boessenkool <segher at gcc dot gnu.org> ---
Note avr has an "any_extract" code_iterator for this.  That of course
is a crutch but could be a workaround for you for now.