Add SelectionDAG::getNOT method to construct bitwise NOT operations,

corresponding to the "not" and "vnot" PatFrags.  Use the new method
in some places where it seems appropriate.

llvm-svn: 62768

1 files changed, 2 insertions, 4 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
index 608dde21444..10baccbdf99 100644
--- a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
@@ -6318,7 +6318,7 @@ SDValue SelectionDAGLegalize::ExpandBitCount(unsigned Opc, SDValue Op) {
       SDValue Tmp3 = DAG.getConstant(1ULL << i, ShVT);
       Op = DAG.getNode(ISD::OR, VT, Op, DAG.getNode(ISD::SRL, VT, Op, Tmp3));
     }
-    Op = DAG.getNode(ISD::XOR, VT, Op, DAG.getConstant(~0ULL, VT));
+    Op = DAG.getNOT(Op, VT);
     return DAG.getNode(ISD::CTPOP, VT, Op);
   }
   case ISD::CTTZ: {
@@ -6327,9 +6327,7 @@ SDValue SelectionDAGLegalize::ExpandBitCount(unsigned Opc, SDValue Op) {
     // { return 32 - nlz(~x & (x-1)); }
     // see also http://www.hackersdelight.org/HDcode/ntz.cc
     MVT VT = Op.getValueType();
-    SDValue Tmp2 = DAG.getConstant(~0ULL, VT);
-    SDValue Tmp3 = DAG.getNode(ISD::AND, VT,
-                       DAG.getNode(ISD::XOR, VT, Op, Tmp2),
+    SDValue Tmp3 = DAG.getNode(ISD::AND, VT, DAG.getNOT(Op, VT),
                        DAG.getNode(ISD::SUB, VT, Op, DAG.getConstant(1, VT)));
     // If ISD::CTLZ is legal and CTPOP isn't, then do that instead.
     if (!TLI.isOperationLegal(ISD::CTPOP, VT) &&