[PATCH] D42737: [LegalizeDAG] Support expanding condition operand of ISD::SELECT

[Eli Friedman via Phabricator via llvm-commits]

efriedma added a comment.

It seems a little dubious to create a SELECT where the condition isn't either an i1 or a naturally promoted i1... maybe it would make sense to restrict that instead?  (And fix the VSELECT expansion to just truncate the condition instead of trying to get fancy.)



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Comment at: lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp:3118
+  return DAG.getNode(ISD::SELECT, SDLoc(N), N->getValueType(0), InL,
+                     N->getOperand(1), N->getOperand(2));
+}
----------------
Probably want to clarify that you're intentionally throwing away the high bits because the operand is required to conform to getBooleanContents.


https://reviews.llvm.org/D42737