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Re: subreg_get_info vs mode restrictions in registers?
> I believe we've generally assumed that all hard registers can be
> subreg'd. That said, HARD_REGNO_MODE_OK should keep QImode values
> out of those registers. And insn constraints should keep reload
> from using those registers for QImode insns. So can you expand on
> what is actually going wrong?
Ok, I tried letting it put QImode values in any register. Now it's
trying to figure out how many 32 bit values it can stuff into a 24 bit
register.
Since the function returns an int, I'm not sure how to answer.
Is HARD_REGNO_NREGS *required* to return a positive value, no matter
what the chip actually supports?