[PATCH] D61411: [SelectionDAG] Expand ADD/SUBCARRY

[Eli Friedman via Phabricator via llvm-commits]

efriedma added inline comments.


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Comment at: llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp:3292
+    // Add of the sum and the carry.
+    SDValue CarryExt = DAG.getZExtOrTrunc(Carry, dl, VT);
+    SDValue Sum2 = DAG.getNode(Op, dl, VT, Sum, CarryExt);
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Looking at this again, it isn't quite right.  In general, on targets where getBooleanContents does not return ZeroOrOneBooleanContent, you need to getZeroExtendInReg to convert a carry bit to 1/0.


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CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D61411/new/

https://reviews.llvm.org/D61411