[PATCH] D48223: Allow binop C1, (select cc, CF, CT) -> select folding

[Sanjay Patel via Phabricator via llvm-commits]

spatel added inline comments.


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Comment at: lib/CodeGen/SelectionDAG/DAGCombiner.cpp:1904
+  // Bail out if any constants are opaque because we can't constant fold those.
+  SDValue C1 = BO->getOperand(SelOpNo ^ 1);
+  if (!isConstantOrConstantVector(C1, true) &&
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Nit: I'd call this 'C' or 'CBO' or 'CBinOp' since it's not always operand 1 now.


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Comment at: lib/CodeGen/SelectionDAG/DAGCombiner.cpp:1913-1914
   EVT VT = Sel.getValueType();
+  if (SelOpNo && VT != C1.getValueType())
+    return SDValue();
+
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When does this happen (is there a test)? Why does this only happen when the select is operand 1 of the binop? Better to remove the 'SelOpNo' condition to be safer?


https://reviews.llvm.org/D48223