[LLVMdev] ADDE on HW that doesn't have flags?

Duncan Sands baldrick at free.fr
Mon Oct 27 09:34:06 PDT 2008

> ADDE should only be generated if you specify ADDC as legal.  If ADDC
> is illegal, larger integer arith will be lowered to add and cmp
> sequences rather than addc adde sequences.

That said, it would be nice if ADDE/ADDC could be expanded into
code sequences.  The main problem is that there seems to be no
way to generate results of type MVT::Flag (ADDC is supposed to
produce one, and ADDE consume one).



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