Revert r338222 "[DAGCombiner] Remove unnecessary calls to AddToWorklist."

Thinking about it more it might be possible for the later nodes to be folded in getNode in such a way that the other created nodes are left dead. This can cause use counts to be incorrect on nodes that aren't dead.

So its probably safer to leave this alone.

llvm-svn: 338298

1 files changed, 46 insertions, 8 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 05ad1ee25a4..8ee1cb6ffff 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -3346,12 +3346,14 @@ SDValue DAGCombiner::visitREM(SDNode *N) {
     if (DAG.isKnownToBeAPowerOfTwo(N1)) {
       // fold (urem x, pow2) -> (and x, pow2-1)
       SDValue Add = DAG.getNode(ISD::ADD, DL, VT, N1, NegOne);
+      AddToWorklist(Add.getNode());
       return DAG.getNode(ISD::AND, DL, VT, N0, Add);
     }
     if (N1.getOpcode() == ISD::SHL &&
         DAG.isKnownToBeAPowerOfTwo(N1.getOperand(0))) {
       // fold (urem x, (shl pow2, y)) -> (and x, (add (shl pow2, y), -1))
       SDValue Add = DAG.getNode(ISD::ADD, DL, VT, N1, NegOne);
+      AddToWorklist(Add.getNode());
       return DAG.getNode(ISD::AND, DL, VT, N0, Add);
     }
   }
@@ -3371,7 +3373,10 @@ SDValue DAGCombiner::visitREM(SDNode *N) {
     if (OptimizedDiv.getNode() && OptimizedDiv.getOpcode() != ISD::UDIVREM &&
         OptimizedDiv.getOpcode() != ISD::SDIVREM) {
       SDValue Mul = DAG.getNode(ISD::MUL, DL, VT, OptimizedDiv, N1);
-      return DAG.getNode(ISD::SUB, DL, VT, N0, Mul);
+      SDValue Sub = DAG.getNode(ISD::SUB, DL, VT, N0, Mul);
+      AddToWorklist(OptimizedDiv.getNode());
+      AddToWorklist(Mul.getNode());
+      return Sub;
     }
   }
 
@@ -5122,6 +5127,7 @@ SDValue DAGCombiner::visitOR(SDNode *N) {
     if (SDValue COR = DAG.FoldConstantArithmetic(
             ISD::OR, SDLoc(N1), VT, N1.getNode(), N0.getOperand(1).getNode())) {
       SDValue IOR = DAG.getNode(ISD::OR, SDLoc(N0), VT, N0.getOperand(0), N1);
+      AddToWorklist(IOR.getNode());
       return DAG.getNode(ISD::AND, SDLoc(N), VT, COR, IOR);
     }
   }
@@ -6017,6 +6023,7 @@ SDValue DAGCombiner::visitXOR(SDNode *N) {
     SDLoc DL(N0);
     V = DAG.getNode(ISD::XOR, DL, V.getValueType(), V,
                     DAG.getConstant(1, DL, V.getValueType()));
+    AddToWorklist(V.getNode());
     return DAG.getNode(ISD::ZERO_EXTEND, SDLoc(N), VT, V);
   }
 
@@ -6028,6 +6035,7 @@ SDValue DAGCombiner::visitXOR(SDNode *N) {
       unsigned NewOpcode = N0.getOpcode() == ISD::AND ? ISD::OR : ISD::AND;
       LHS = DAG.getNode(ISD::XOR, SDLoc(LHS), VT, LHS, N1); // LHS = ~LHS
       RHS = DAG.getNode(ISD::XOR, SDLoc(RHS), VT, RHS, N1); // RHS = ~RHS
+      AddToWorklist(LHS.getNode()); AddToWorklist(RHS.getNode());
       return DAG.getNode(NewOpcode, SDLoc(N), VT, LHS, RHS);
     }
   }
@@ -6039,6 +6047,7 @@ SDValue DAGCombiner::visitXOR(SDNode *N) {
       unsigned NewOpcode = N0.getOpcode() == ISD::AND ? ISD::OR : ISD::AND;
       LHS = DAG.getNode(ISD::XOR, SDLoc(LHS), VT, LHS, N1); // LHS = ~LHS
       RHS = DAG.getNode(ISD::XOR, SDLoc(RHS), VT, RHS, N1); // RHS = ~RHS
+      AddToWorklist(LHS.getNode()); AddToWorklist(RHS.getNode());
       return DAG.getNode(NewOpcode, SDLoc(N), VT, LHS, RHS);
     }
   }
@@ -6047,6 +6056,7 @@ SDValue DAGCombiner::visitXOR(SDNode *N) {
       N0->getOperand(1) == N1) {
     SDValue X = N0->getOperand(0);
     SDValue NotX = DAG.getNOT(SDLoc(X), X, VT);
+    AddToWorklist(NotX.getNode());
     return DAG.getNode(ISD::AND, SDLoc(N), VT, NotX, N1);
   }
 
@@ -6407,6 +6417,7 @@ SDValue DAGCombiner::visitSHL(SDNode *N) {
           SDValue NewSHL = DAG.getNode(ISD::SHL, DL, NewOp0.getValueType(),
                                        NewOp0,
                                        DAG.getConstant(c2, DL, CountVT));
+          AddToWorklist(NewSHL.getNode());
           return DAG.getNode(ISD::ZERO_EXTEND, SDLoc(N0), VT, NewSHL);
         }
       }
@@ -6477,6 +6488,8 @@ SDValue DAGCombiner::visitSHL(SDNode *N) {
       isConstantOrConstantVector(N0.getOperand(1), /* No Opaques */ true)) {
     SDValue Shl0 = DAG.getNode(ISD::SHL, SDLoc(N0), VT, N0.getOperand(0), N1);
     SDValue Shl1 = DAG.getNode(ISD::SHL, SDLoc(N1), VT, N0.getOperand(1), N1);
+    AddToWorklist(Shl0.getNode());
+    AddToWorklist(Shl1.getNode());
     return DAG.getNode(N0.getOpcode(), SDLoc(N), VT, Shl0, Shl1);
   }
 
@@ -6758,6 +6771,7 @@ SDValue DAGCombiner::visitSRL(SDNode *N) {
     SDLoc DL(N);
     SDValue Mask =
         DAG.getNode(ISD::SRL, DL, VT, DAG.getAllOnesConstant(DL, VT), N1);
+    AddToWorklist(Mask.getNode());
     return DAG.getNode(ISD::AND, DL, VT, N0.getOperand(0), Mask);
   }
 
@@ -6776,6 +6790,7 @@ SDValue DAGCombiner::visitSRL(SDNode *N) {
                                        N0.getOperand(0),
                           DAG.getConstant(ShiftAmt, DL0,
                                           getShiftAmountTy(SmallVT)));
+      AddToWorklist(SmallShift.getNode());
       APInt Mask = APInt::getLowBitsSet(OpSizeInBits, OpSizeInBits - ShiftAmt);
       SDLoc DL(N);
       return DAG.getNode(ISD::AND, DL, VT,
@@ -6820,6 +6835,7 @@ SDValue DAGCombiner::visitSRL(SDNode *N) {
         Op = DAG.getNode(ISD::SRL, DL, VT, Op,
                   DAG.getConstant(ShAmt, DL,
                                   getShiftAmountTy(Op.getValueType())));
+        AddToWorklist(Op.getNode());
       }
 
       SDLoc DL(N);
@@ -7145,11 +7161,13 @@ SDValue DAGCombiner::visitSELECT(SDNode *N) {
   // fold (select C, 0, X) -> (and (not C), X)
   if (VT == VT0 && VT == MVT::i1 && isNullConstant(N1)) {
     SDValue NOTNode = DAG.getNOT(SDLoc(N0), N0, VT);
+    AddToWorklist(NOTNode.getNode());
     return DAG.getNode(ISD::AND, DL, VT, NOTNode, N2);
   }
   // fold (select C, X, 1) -> (or (not C), X)
   if (VT == VT0 && VT == MVT::i1 && isOneConstant(N2)) {
     SDValue NOTNode = DAG.getNOT(SDLoc(N0), N0, VT);
+    AddToWorklist(NOTNode.getNode());
     return DAG.getNode(ISD::OR, DL, VT, NOTNode, N1);
   }
   // fold (select X, Y, X) -> (and X, Y)
@@ -7721,6 +7739,8 @@ SDValue DAGCombiner::visitVSELECT(SDNode *N) {
           ISD::SRA, DL, VT, LHS,
           DAG.getConstant(VT.getScalarSizeInBits() - 1, DL, VT));
       SDValue Add = DAG.getNode(ISD::ADD, DL, VT, LHS, Shift);
+      AddToWorklist(Shift.getNode());
+      AddToWorklist(Add.getNode());
       return DAG.getNode(ISD::XOR, DL, VT, Add, Shift);
     }
 
@@ -9436,8 +9456,10 @@ SDValue DAGCombiner::visitTRUNCATE(SDNode *N) {
       EVT AmtVT = TLI.getShiftAmountTy(VT, DAG.getDataLayout());
 
       SDValue Trunc = DAG.getNode(ISD::TRUNCATE, SL, VT, N0.getOperand(0));
-      if (AmtVT != Amt.getValueType())
+      if (AmtVT != Amt.getValueType()) {
         Amt = DAG.getZExtOrTrunc(Amt, SL, AmtVT);
+        AddToWorklist(Amt.getNode());
+      }
       return DAG.getNode(ISD::SHL, SL, VT, Trunc, Amt);
     }
   }
@@ -9541,6 +9563,7 @@ SDValue DAGCombiner::visitTRUNCATE(SDNode *N) {
           continue;
         }
         SDValue NV = DAG.getNode(ISD::TRUNCATE, SDLoc(V), VTs[i], V);
+        AddToWorklist(NV.getNode());
         Opnds.push_back(NV);
       }
       return DAG.getNode(ISD::CONCAT_VECTORS, SDLoc(N), VT, Opnds);
@@ -10844,9 +10867,10 @@ SDValue DAGCombiner::visitFADD(SDNode *N) {
   } // enable-unsafe-fp-math
 
   // FADD -> FMA combines:
-  if (SDValue Fused = visitFADDForFMACombine(N))
+  if (SDValue Fused = visitFADDForFMACombine(N)) {
+    AddToWorklist(Fused.getNode());
     return Fused;
-
+  }
   return SDValue();
 }
 
@@ -10918,8 +10942,10 @@ SDValue DAGCombiner::visitFSUB(SDNode *N) {
   }
 
   // FSUB -> FMA combines:
-  if (SDValue Fused = visitFSUBForFMACombine(N))
+  if (SDValue Fused = visitFSUBForFMACombine(N)) {
+    AddToWorklist(Fused.getNode());
     return Fused;
+  }
 
   return SDValue();
 }
@@ -11068,8 +11094,10 @@ SDValue DAGCombiner::visitFMUL(SDNode *N) {
   }
 
   // FMUL -> FMA combines:
-  if (SDValue Fused = visitFMULForFMADistributiveCombine(N))
+  if (SDValue Fused = visitFMULForFMADistributiveCombine(N)) {
+    AddToWorklist(Fused.getNode());
     return Fused;
+  }
 
   return SDValue();
 }
@@ -11144,6 +11172,7 @@ SDValue DAGCombiner::visitFMA(SDNode *N) {
     if (N1CFP->isExactlyValue(-1.0) &&
         (!LegalOperations || TLI.isOperationLegal(ISD::FNEG, VT))) {
       SDValue RHSNeg = DAG.getNode(ISD::FNEG, DL, VT, N0);
+      AddToWorklist(RHSNeg.getNode());
       // TODO: The FMA node should have flags that propagate to this node.
       return DAG.getNode(ISD::FADD, DL, VT, N2, RHSNeg);
     }
@@ -11295,6 +11324,7 @@ SDValue DAGCombiner::visitFDIV(SDNode *N) {
       if (SDValue RV = buildRsqrtEstimate(N1.getOperand(0).getOperand(0),
                                           Flags)) {
         RV = DAG.getNode(ISD::FP_EXTEND, SDLoc(N1), VT, RV);
+        AddToWorklist(RV.getNode());
         return DAG.getNode(ISD::FMUL, DL, VT, N0, RV, Flags);
       }
     } else if (N1.getOpcode() == ISD::FP_ROUND &&
@@ -11302,6 +11332,7 @@ SDValue DAGCombiner::visitFDIV(SDNode *N) {
       if (SDValue RV = buildRsqrtEstimate(N1.getOperand(0).getOperand(0),
                                           Flags)) {
         RV = DAG.getNode(ISD::FP_ROUND, SDLoc(N1), VT, RV, N1.getOperand(1));
+        AddToWorklist(RV.getNode());
         return DAG.getNode(ISD::FMUL, DL, VT, N0, RV, Flags);
       }
     } else if (N1.getOpcode() == ISD::FMUL) {
@@ -11321,15 +11352,17 @@ SDValue DAGCombiner::visitFDIV(SDNode *N) {
         // x / (y * sqrt(z)) -> x * (rsqrt(z) / y)
         if (SDValue RV = buildRsqrtEstimate(SqrtOp.getOperand(0), Flags)) {
           RV = DAG.getNode(ISD::FDIV, SDLoc(N1), VT, RV, OtherOp, Flags);
+          AddToWorklist(RV.getNode());
           return DAG.getNode(ISD::FMUL, DL, VT, N0, RV, Flags);
         }
       }
     }
 
     // Fold into a reciprocal estimate and multiply instead of a real divide.
-    if (SDValue RV = BuildReciprocalEstimate(N1, Flags))
+    if (SDValue RV = BuildReciprocalEstimate(N1, Flags)) {
+      AddToWorklist(RV.getNode());
       return DAG.getNode(ISD::FMUL, DL, VT, N0, RV, Flags);
-
+    }
   }
 
   // (fdiv (fneg X), (fneg Y)) -> (fdiv X, Y)
@@ -11689,6 +11722,7 @@ SDValue DAGCombiner::visitFP_ROUND(SDNode *N) {
   if (N0.getOpcode() == ISD::FCOPYSIGN && N0.getNode()->hasOneUse()) {
     SDValue Tmp = DAG.getNode(ISD::FP_ROUND, SDLoc(N0), VT,
                               N0.getOperand(0), N1);
+    AddToWorklist(Tmp.getNode());
     return DAG.getNode(ISD::FCOPYSIGN, SDLoc(N), VT,
                        Tmp, N0.getOperand(1));
   }
@@ -11848,6 +11882,7 @@ SDValue DAGCombiner::visitFNEG(SDNode *N) {
       SDLoc DL0(N0);
       Int = DAG.getNode(ISD::XOR, DL0, IntVT, Int,
                         DAG.getConstant(SignMask, DL0, IntVT));
+      AddToWorklist(Int.getNode());
       return DAG.getBitcast(VT, Int);
     }
   }
@@ -11952,6 +11987,7 @@ SDValue DAGCombiner::visitFABS(SDNode *N) {
       SDLoc DL(N0);
       Int = DAG.getNode(ISD::AND, DL, IntVT, Int,
                         DAG.getConstant(SignMask, DL, IntVT));
+      AddToWorklist(Int.getNode());
       return DAG.getBitcast(N->getValueType(0), Int);
     }
   }
@@ -14960,6 +14996,7 @@ SDValue DAGCombiner::visitINSERT_VECTOR_ELT(SDNode *N) {
       // Swap nodes.
       SDValue NewOp = DAG.getNode(ISD::INSERT_VECTOR_ELT, DL, VT,
                                   InVec.getOperand(0), InVal, EltNo);
+      AddToWorklist(NewOp.getNode());
       return DAG.getNode(ISD::INSERT_VECTOR_ELT, SDLoc(InVec.getNode()),
                          VT, NewOp, InVec.getOperand(1), InVec.getOperand(2));
     }
@@ -17345,6 +17382,7 @@ SDValue DAGCombiner::visitINSERT_SUBVECTOR(SDNode *N) {
       // Swap nodes.
       SDValue NewOp = DAG.getNode(ISD::INSERT_SUBVECTOR, SDLoc(N), VT,
                                   N0.getOperand(0), N1, N2);
+      AddToWorklist(NewOp.getNode());
       return DAG.getNode(ISD::INSERT_SUBVECTOR, SDLoc(N0.getNode()),
                          VT, NewOp, N0.getOperand(1), N0.getOperand(2));
     }