https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102569

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2021-10-04
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW
           Keywords|TREE                        |

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
Confirmed.  VN could indeed add alternate expression variants for the overflow
IFNs.  But note we have to care for the IMAGPART eventually getting unused
and fold the IFN back to a bare PLUS (I guess we already to that part).
It will also get tricky when we see

  _1 = _2 + _3;
  _4 = .ADD_OVERFLOW (_2, _3);
  _5 = REALPART_EXPR <_4>;
  _6 = IMAGPART_EXPR <_4>;

where we don't want to replace _5 with _1 and we cannot generally replace
_1 with _5 ...

So it would be interesting to see real-world cases where we miss opportunities.

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