Remove redundant DAG.ReplaceAllUsesWith(LHS, ANDSNode) and LHS.getOpcode() == AArch64ISD::ANDS substitutions

We already handle that now elsewhere.

Author: AZero13

llvm/lib/Target/AArch64/AArch64ISelLowering.cpp

@@ -3747,17 +3747,11 @@ static SDValue emitComparison(SDValue LHS, SDValue RHS, ISD::CondCode CC,
   } else if (isNullConstant(RHS) && !isUnsignedIntSetCC(CC)) {
     if (LHS.getOpcode() == ISD::AND) {
       // Similarly, (CMP (and X, Y), 0) can be implemented with a TST
-      // (a.k.a. ANDS) except that the flags are only guaranteed to work for one
-      // of the signed comparisons.
-      const SDValue ANDSNode =
-          DAG.getNode(AArch64ISD::ANDS, DL, DAG.getVTList(VT, FlagsVT),
-                      LHS.getOperand(0), LHS.getOperand(1));
-      // Replace all users of (and X, Y) with newly generated (ands X, Y)
-      DAG.ReplaceAllUsesWith(LHS, ANDSNode);
-      return ANDSNode.getValue(1);
-    } else if (LHS.getOpcode() == AArch64ISD::ANDS) {
-      // Use result of ANDS
-      return LHS.getValue(1);
+      // (a.k.a. ANDS) except that the flags are only guaranteed to work for
+      // signed comparisons.
+      Opcode = AArch64ISD::ANDS;
+      RHS = LHS.getOperand(1);
+      LHS = LHS.getOperand(0);
     }
   }