[X86] commuteSelect - update to use SDPatternMatch. NFC. (#146868)

Author: RKSimon

llvm/lib/Target/X86/X86ISelLowering.cpp

@@ -47568,31 +47568,26 @@ static SDValue combineLogicBlendIntoConditionalNegate(
 
 static SDValue commuteSelect(SDNode *N, SelectionDAG &DAG, const SDLoc &DL,
                              const X86Subtarget &Subtarget) {
+  using namespace SDPatternMatch;
   if (!Subtarget.hasAVX512())
     return SDValue();
-  if (N->getOpcode() != ISD::VSELECT)
-    return SDValue();
-
-  SDValue Cond = N->getOperand(0);
-  SDValue LHS = N->getOperand(1);
-  SDValue RHS = N->getOperand(2);
-
-  if (canCombineAsMaskOperation(LHS, Subtarget))
-    return SDValue();
 
-  if (!canCombineAsMaskOperation(RHS, Subtarget))
+  ISD::CondCode CC;
+  SDValue Cond, X, Y, LHS, RHS;
+  if (!sd_match(N, m_VSelect(m_AllOf(m_Value(Cond),
+                                     m_OneUse(m_SetCC(m_Value(X), m_Value(Y),
+                                                      m_CondCode(CC)))),
+                             m_Value(LHS), m_Value(RHS))))
     return SDValue();
 
-  if (Cond.getOpcode() != ISD::SETCC || !Cond.hasOneUse())
+  if (canCombineAsMaskOperation(LHS, Subtarget) ||
+      !canCombineAsMaskOperation(RHS, Subtarget))
     return SDValue();
 
   // Commute LHS and RHS to create opportunity to select mask instruction.
   // (vselect M, L, R) -> (vselect ~M, R, L)
-  ISD::CondCode NewCC =
-      ISD::getSetCCInverse(cast<CondCodeSDNode>(Cond.getOperand(2))->get(),
-                           Cond.getOperand(0).getValueType());
-  Cond = DAG.getSetCC(SDLoc(Cond), Cond.getValueType(), Cond.getOperand(0),
-                      Cond.getOperand(1), NewCC);
+  ISD::CondCode NewCC = ISD::getSetCCInverse(CC, X.getValueType());
+  Cond = DAG.getSetCC(SDLoc(Cond), Cond.getValueType(), X, Y, NewCC);
   return DAG.getSelect(DL, LHS.getValueType(), Cond, RHS, LHS);
 }