[Bug target/68277] [5/6 Regression] [SH]: error: insn does not satisfy its constraints when compiling erlang

[kkojima at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68277

--- Comment #4 from Kazumoto Kojima <kkojima at gcc dot gnu.org> ---
(In reply to Oleg Endo from comment #3)
> I haven't read reload.*, but my speculation is that if something in reload
> instantiates that rtx with an imm8 constant to calculate addresses, it might
> also try to instantiate it with reg = reg + reg if the constant doesn't fit
> into imm8.  Maybe we just don't hit the case (yet).  So it's probably safer
> to allow reg = reg + reg, too.

Sounds reasonable.

> I guess those "new" failures are R0 related?

Yep, spill failure in R0.  Our old friend.