[DAG] SimplifyDemandedBits - call demanded elts variant directly for SELECT/SELECT_CC nodes.

Don't rebuild the demanded elts mask every time.

Author: RKSimon

llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp

@@ -1645,11 +1645,11 @@ bool TargetLowering::SimplifyDemandedBits(
     break;
   }
   case ISD::SELECT:
-    if (SimplifyDemandedBits(Op.getOperand(2), DemandedBits, Known, TLO,
-                             Depth + 1))
+    if (SimplifyDemandedBits(Op.getOperand(2), DemandedBits, DemandedElts,
+                             Known, TLO, Depth + 1))
       return true;
-    if (SimplifyDemandedBits(Op.getOperand(1), DemandedBits, Known2, TLO,
-                             Depth + 1))
+    if (SimplifyDemandedBits(Op.getOperand(1), DemandedBits, DemandedElts,
+                             Known2, TLO, Depth + 1))
       return true;
     assert(!Known.hasConflict() && "Bits known to be one AND zero?");
     assert(!Known2.hasConflict() && "Bits known to be one AND zero?");
@@ -1675,11 +1675,11 @@ bool TargetLowering::SimplifyDemandedBits(
     Known = Known.intersectWith(Known2);
     break;
   case ISD::SELECT_CC:
-    if (SimplifyDemandedBits(Op.getOperand(3), DemandedBits, Known, TLO,
-                             Depth + 1))
+    if (SimplifyDemandedBits(Op.getOperand(3), DemandedBits, DemandedElts,
+                             Known, TLO, Depth + 1))
       return true;
-    if (SimplifyDemandedBits(Op.getOperand(2), DemandedBits, Known2, TLO,
-                             Depth + 1))
+    if (SimplifyDemandedBits(Op.getOperand(2), DemandedBits, DemandedElts,
+                             Known2, TLO, Depth + 1))
       return true;
     assert(!Known.hasConflict() && "Bits known to be one AND zero?");
     assert(!Known2.hasConflict() && "Bits known to be one AND zero?");