reload vs adds with clobbers

[Richard Kenner]

    > What's "right"?  If an addition needs a scratch register (it was said
    > that it had a CLOBBER), the only way to produce that is via the secondary
    > reloads.  The approach above sounds exactly correct.

    It needs to clobber the carry, nothing else.  But I see your point.

For those who might not, the "carry" here is a "scratch register"
since there could well be code that depends on it being preserved
across that insn.