[SelectionDAG] Add helper guard to automatically insert flags

[qiucf]

Summary

The idea is from review of D87037, @spatel 's comments.

This is like FastMathFlagGuard in IR. Since we use SDAG instance to get values, it's with SelectionDAG. By creating a FlagInserter in current scope, all values created by getNode will get the flags, unless explicitly use Inserter->disable().

It's a prototype so in this revision I only enabled in visitFMA to show the same flag propagation as D87037.

[steven.zhang]

llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp

4413

This is not right as you override the Flags secretly. How about having another version that didn't have the Flags parameter and we will get it from Inserter. And one version that has the Flags if people really want to set the flags manually.(I wonder if there is such case)

[qiucf]

Keep flags in current methods and introduce new methods to auto-insert flags. (maybe can use variadic template methods?)

[qiucf]

Remove flag passing in methods visiting floating-point nodes.

[spatel]

LGTM - this makes it more likely that we propagate as expected and cleans up the current code.
We probably have more cases like D88063, but that can be handled as follow-up patches.

llvm/include/llvm/CodeGen/SelectionDAG.h

DAGNodeDeletedListener(SelectionDAG &DAG,
         : DAGUpdateListener(DAG), Callback(std::move(Callback)) {}
 
     void NodeDeleted(SDNode *N, SDNode *E) override { Callback(N, E); }
 
    private:
     virtual void anchor();
   };
 
+  /// Help to insert SDNodeFlags automatically in transforming. Use
+  /// RAII to save and resume flags in current scope.
+  class FlagInserter {
+    SelectionDAG &DAG;
+    SDNodeFlags Flags;
+    FlagInserter *LastInserter;
+    bool Disabled;
+
+  public:
+    FlagInserter(SelectionDAG &SDAG, SDNode *N)
+        : DAG(SDAG), Flags(N->getFlags()), LastInserter(SDAG.getFlagInserter()),
+          Disabled(false) {
+      SDAG.setFlagInserter(this);
+    }
+
+    FlagInserter(const FlagInserter &) = delete;
+    FlagInserter &operator=(const FlagInserter &) = delete;
+    ~FlagInserter() { DAG.setFlagInserter(LastInserter); }
+
+    const SDNodeFlags getFlags() const { return Flags; }
+  };
+
   /// When true, additional steps are taken to
   /// ensure that getConstant() and similar functions return DAG nodes that
   /// have legal types. This is important after type legalization since
   /// any illegally typed nodes generated after this point will not experience
   /// type legalization.
   bool NewNodesMustHaveLegalTypes = false;
 
 private:
public:
   const TargetLibraryInfo &getLibInfo() const { return *LibInfo; }
   const SelectionDAGTargetInfo &getSelectionDAGInfo() const { return *TSI; }
   const LegacyDivergenceAnalysis *getDivergenceAnalysis() const { return DA; }
   LLVMContext *getContext() const { return Context; }
   OptimizationRemarkEmitter &getORE() const { return *ORE; }
   ProfileSummaryInfo *getPSI() const { return PSI; }
   BlockFrequencyInfo *getBFI() const { return BFI; }
 
+  FlagInserter *getFlagInserter() { return Inserter; }
+  void setFlagInserter(FlagInserter *FI) { Inserter = FI; }
+
   /// Just dump dot graph to a user-provided path and title.
   /// This doesn't open the dot viewer program and
   /// helps visualization when outside debugging session.
   /// FileName expects absolute path. If provided
   /// without any path separators then the file
   /// will be created in the current directory.
   /// Error will be emitted if the path is insane.
 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
SDValue getGLOBAL_OFFSET_TABLE(EVT VT) {
     return getNode(ISD::GLOBAL_OFFSET_TABLE, SDLoc(), VT);
   }
 
   /// Gets or creates the specified node.
   ///
   SDValue getNode(unsigned Opcode, const SDLoc &DL, EVT VT,
                   ArrayRef<SDUse> Ops);
   SDValue getNode(unsigned Opcode, const SDLoc &DL, EVT VT,
-                  ArrayRef<SDValue> Ops, const SDNodeFlags Flags = SDNodeFlags());
+                  ArrayRef<SDValue> Ops, const SDNodeFlags Flags);
   SDValue getNode(unsigned Opcode, const SDLoc &DL, ArrayRef<EVT> ResultTys,
                   ArrayRef<SDValue> Ops);
   SDValue getNode(unsigned Opcode, const SDLoc &DL, SDVTList VTList,
-                  ArrayRef<SDValue> Ops, const SDNodeFlags Flags = SDNodeFlags());
+                  ArrayRef<SDValue> Ops, const SDNodeFlags Flags);
+
+  // Use flags from current flag inserter.
+  SDValue getNode(unsigned Opcode, const SDLoc &DL, EVT VT,
+                  ArrayRef<SDValue> Ops);
+  SDValue getNode(unsigned Opcode, const SDLoc &DL, SDVTList VTList,
+                  ArrayRef<SDValue> Ops);
+  SDValue getNode(unsigned Opcode, const SDLoc &DL, EVT VT, SDValue Operand);
+  SDValue getNode(unsigned Opcode, const SDLoc &DL, EVT VT, SDValue N1,
+                  SDValue N2);
+  SDValue getNode(unsigned Opcode, const SDLoc &DL, EVT VT, SDValue N1,
+                  SDValue N2, SDValue N3);
 
   // Specialize based on number of operands.
   SDValue getNode(unsigned Opcode, const SDLoc &DL, EVT VT);
   SDValue getNode(unsigned Opcode, const SDLoc &DL, EVT VT, SDValue Operand,
-                  const SDNodeFlags Flags = SDNodeFlags());
+                  const SDNodeFlags Flags);
   SDValue getNode(unsigned Opcode, const SDLoc &DL, EVT VT, SDValue N1,
-                  SDValue N2, const SDNodeFlags Flags = SDNodeFlags());
+                  SDValue N2, const SDNodeFlags Flags);
   SDValue getNode(unsigned Opcode, const SDLoc &DL, EVT VT, SDValue N1,
-                  SDValue N2, SDValue N3,
-                  const SDNodeFlags Flags = SDNodeFlags());
+                  SDValue N2, SDValue N3, const SDNodeFlags Flags);
   SDValue getNode(unsigned Opcode, const SDLoc &DL, EVT VT, SDValue N1,
                   SDValue N2, SDValue N3, SDValue N4);
   SDValue getNode(unsigned Opcode, const SDLoc &DL, EVT VT, SDValue N1,
                   SDValue N2, SDValue N3, SDValue N4, SDValue N5);
 
   // Specialize again based on number of operands for nodes with a VTList
   // rather than a single VT.
   SDValue getNode(unsigned Opcode, const SDLoc &DL, SDVTList VTList);
#endif
   SDValue getTargetExtractSubreg(int SRIdx, const SDLoc &DL, EVT VT,
                                  SDValue Operand);
 
   /// A convenience function for creating TargetInstrInfo::INSERT_SUBREG nodes.
   SDValue getTargetInsertSubreg(int SRIdx, const SDLoc &DL, EVT VT,
                                 SDValue Operand, SDValue Subreg);
 
   /// Get the specified node if it's already available, or else return NULL.
-  SDNode *getNodeIfExists(unsigned Opcode, SDVTList VTList, ArrayRef<SDValue> Ops,
-                          const SDNodeFlags Flags = SDNodeFlags());
+  SDNode *getNodeIfExists(unsigned Opcode, SDVTList VTList,
+                          ArrayRef<SDValue> Ops, const SDNodeFlags Flags);
+  SDNode *getNodeIfExists(unsigned Opcode, SDVTList VTList,
+                          ArrayRef<SDValue> Ops);
 
   /// Creates a SDDbgValue node.
   SDDbgValue *getDbgValue(DIVariable *Var, DIExpression *Expr, SDNode *N,
                           unsigned R, bool IsIndirect, const DebugLoc &DL,
                           unsigned O);
 
   /// Creates a constant SDDbgValue node.
   SDDbgValue *getConstantDbgValue(DIVariable *Var, DIExpression *Expr,
private:
   std::vector<CondCodeSDNode*> CondCodeNodes;
 
   std::vector<SDNode*> ValueTypeNodes;
   std::map<EVT, SDNode*, EVT::compareRawBits> ExtendedValueTypeNodes;
   StringMap<SDNode*> ExternalSymbols;
 
   std::map<std::pair<std::string, unsigned>, SDNode *> TargetExternalSymbols;
   DenseMap<MCSymbol *, SDNode *> MCSymbols;
+
+  FlagInserter *Inserter = nullptr;
 };
 
 template <> struct GraphTraits<SelectionDAG*> : public GraphTraits<SDNode*> {
   using nodes_iterator = pointer_iterator<SelectionDAG::allnodes_iterator>;
 
   static nodes_iterator nodes_begin(SelectionDAG *G) {
     return nodes_iterator(G->allnodes_begin());
   }

llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp

   SDValue N0 = N->getOperand(0);
   SDValue N1 = N->getOperand(1);
   bool N0CFP = isConstantFPBuildVectorOrConstantFP(N0);
   bool N1CFP = isConstantFPBuildVectorOrConstantFP(N1);
   EVT VT = N->getValueType(0);
   SDLoc DL(N);
   const TargetOptions &Options = DAG.getTarget().Options;
   const SDNodeFlags Flags = N->getFlags();
+  SelectionDAG::FlagInserter FlagsInserter(DAG, N);
 
   if (SDValue R = DAG.simplifyFPBinop(N->getOpcode(), N0, N1, Flags))
     return R;
 
   // fold vector ops
   if (VT.isVector())
     if (SDValue FoldedVOp = SimplifyVBinOp(N))
       return FoldedVOp;

   SDValue N0 = N->getOperand(0);
   SDValue N1 = N->getOperand(1);
   ConstantFPSDNode *N0CFP = isConstOrConstSplatFP(N0, true);
   ConstantFPSDNode *N1CFP = isConstOrConstSplatFP(N1, true);
   EVT VT = N->getValueType(0);
   SDLoc DL(N);
   const TargetOptions &Options = DAG.getTarget().Options;
   const SDNodeFlags Flags = N->getFlags();
+  SelectionDAG::FlagInserter FlagsInserter(DAG, N);
 
   if (SDValue R = DAG.simplifyFPBinop(N->getOpcode(), N0, N1, Flags))
     return R;
 
   // fold vector ops
   if (VT.isVector())
     if (SDValue FoldedVOp = SimplifyVBinOp(N))
       return FoldedVOp;

   SDValue N0 = N->getOperand(0);
   SDValue N1 = N->getOperand(1);
   ConstantFPSDNode *N0CFP = isConstOrConstSplatFP(N0, true);
   ConstantFPSDNode *N1CFP = isConstOrConstSplatFP(N1, true);
   EVT VT = N->getValueType(0);
   SDLoc DL(N);
   const TargetOptions &Options = DAG.getTarget().Options;
   const SDNodeFlags Flags = N->getFlags();
+  SelectionDAG::FlagInserter FlagsInserter(DAG, N);
 
   if (SDValue R = DAG.simplifyFPBinop(N->getOpcode(), N0, N1, Flags))
     return R;
 
   // fold vector ops
   if (VT.isVector()) {
     // This just handles C1 * C2 for vectors. Other vector folds are below.
     if (SDValue FoldedVOp = SimplifyVBinOp(N))

   SDValue N0 = N->getOperand(0);
   SDValue N1 = N->getOperand(1);
   SDValue N2 = N->getOperand(2);
   ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
   ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1);
   EVT VT = N->getValueType(0);
   SDLoc DL(N);
   const TargetOptions &Options = DAG.getTarget().Options;
+  SelectionDAG::FlagInserter FlagsInserter(DAG, N);
 
   // FMA nodes have flags that propagate to the created nodes.
   const SDNodeFlags Flags = N->getFlags();
   bool UnsafeFPMath = Options.UnsafeFPMath || isContractable(N);
 
   // Constant fold FMA.
   if (isa<ConstantFPSDNode>(N0) &&
       isa<ConstantFPSDNode>(N1) &&

   SDValue N0 = N->getOperand(0);
   SDValue N1 = N->getOperand(1);
   ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
   ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1);
   EVT VT = N->getValueType(0);
   SDLoc DL(N);
   const TargetOptions &Options = DAG.getTarget().Options;
   SDNodeFlags Flags = N->getFlags();
+  SelectionDAG::FlagInserter FlagsInserter(DAG, N);
 
   if (SDValue R = DAG.simplifyFPBinop(N->getOpcode(), N0, N1, Flags))
     return R;
 
   // fold vector ops
   if (VT.isVector())
     if (SDValue FoldedVOp = SimplifyVBinOp(N))
       return FoldedVOp;

 
 SDValue DAGCombiner::visitFREM(SDNode *N) {
   SDValue N0 = N->getOperand(0);
   SDValue N1 = N->getOperand(1);
   ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
   ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1);
   EVT VT = N->getValueType(0);
   SDNodeFlags Flags = N->getFlags();
+  SelectionDAG::FlagInserter FlagsInserter(DAG, N);
 
   if (SDValue R = DAG.simplifyFPBinop(N->getOpcode(), N0, N1, Flags))
     return R;
 
   // fold (frem c1, c2) -> fmod(c1,c2)
   if (N0CFP && N1CFP)
     return DAG.getNode(ISD::FREM, SDLoc(N), VT, N0, N1, N->getFlags());
 
   if (SDValue NewSel = foldBinOpIntoSelect(N))
     return NewSel;
 
   return SDValue();
 }
 
 SDValue DAGCombiner::visitFSQRT(SDNode *N) {
   SDNodeFlags Flags = N->getFlags();
   const TargetOptions &Options = DAG.getTarget().Options;
+  SelectionDAG::FlagInserter FlagsInserter(DAG, N);
 
   // Require 'ninf' flag since sqrt(+Inf) = +Inf, but the estimation goes as:
   // sqrt(+Inf) == rsqrt(+Inf) * +Inf = 0 * +Inf = NaN
   if ((!Options.UnsafeFPMath && !Flags.hasApproximateFuncs()) ||
       (!Options.NoInfsFPMath && !Flags.hasNoInfs()))
     return SDValue();
 
   SDValue N0 = N->getOperand(0);

   // copysign(x, fp_round(y)) -> copysign(x, y)
   if (CanCombineFCOPYSIGN_EXTEND_ROUND(N))
     return DAG.getNode(ISD::FCOPYSIGN, SDLoc(N), VT, N0, N1.getOperand(0));
 
   return SDValue();
 }
 
 SDValue DAGCombiner::visitFPOW(SDNode *N) {
+  SelectionDAG::FlagInserter FlagsInserter(DAG, N);
+
   ConstantFPSDNode *ExponentC = isConstOrConstSplatFP(N->getOperand(1));
   if (!ExponentC)
     return SDValue();
 
   // Try to convert x ** (1/3) into cube root.
   // TODO: Handle the various flavors of long double.
   // TODO: Since we're approximating, we don't need an exact 1/3 exponent.
   //       Some range near 1/3 should be fine.

     return DAG.getNode(ISD::FFLOOR, SDLoc(N), VT, N0);
 
   return SDValue();
 }
 
 SDValue DAGCombiner::visitFNEG(SDNode *N) {
   SDValue N0 = N->getOperand(0);
   EVT VT = N->getValueType(0);
+  SelectionDAG::FlagInserter FlagsInserter(DAG, N);
 
   // Constant fold FNEG.
   if (isConstantFPBuildVectorOrConstantFP(N0))
     return DAG.getNode(ISD::FNEG, SDLoc(N), VT, N0);
 
   if (SDValue NegN0 =
           TLI.getNegatedExpression(N0, DAG, LegalOperations, ForCodeSize))
     return NegN0;

 static SDValue visitFMinMax(SelectionDAG &DAG, SDNode *N,
                             APFloat (*Op)(const APFloat &, const APFloat &),
                             bool PropagatesNaN) {
   SDValue N0 = N->getOperand(0);
   SDValue N1 = N->getOperand(1);
   EVT VT = N->getValueType(0);
   const ConstantFPSDNode *N0CFP = isConstOrConstSplatFP(N0);
   const ConstantFPSDNode *N1CFP = isConstOrConstSplatFP(N1);
+  SelectionDAG::FlagInserter FlagsInserter(DAG, N);
 
   if (N0CFP && N1CFP) {
     const APFloat &C0 = N0CFP->getValueAPF();
     const APFloat &C1 = N1CFP->getValueAPF();
     return DAG.getConstantFP(Op(C0, C1), SDLoc(N), VT);
   }
 
   // Canonicalize to constant on RHS.

 
 SDValue DAGCombiner::visitFMAXIMUM(SDNode *N) {
   return visitFMinMax(DAG, N, maximum, /* PropagatesNaN */ true);
 }
 
 SDValue DAGCombiner::visitFABS(SDNode *N) {
   SDValue N0 = N->getOperand(0);
   EVT VT = N->getValueType(0);
+  SelectionDAG::FlagInserter FlagsInserter(DAG, N);
 
   // fold (fabs c1) -> fabs(c1)
   if (isConstantFPBuildVectorOrConstantFP(N0))
     return DAG.getNode(ISD::FABS, SDLoc(N), VT, N0);
 
   // fold (fabs (fabs x)) -> (fabs x)
   if (N0.getOpcode() == ISD::FABS)
     return N->getOperand(0);

llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp

   CSEMap.InsertNode(N, IP);
 
   InsertNode(N);
   SDValue V = SDValue(N, 0);
   NewSDValueDbgMsg(V, "Creating new node: ", this);
   return V;
 }
 
+SDValue SelectionDAG::getNode(unsigned Opcode, const SDLoc &DL, EVT VT,
+                              SDValue Operand) {
+  SDNodeFlags Flags;
+  if (Inserter)
+    Flags = Inserter->getFlags();
+  return getNode(Opcode, DL, VT, Operand, Flags);
+}
+
 SDValue SelectionDAG::getNode(unsigned Opcode, const SDLoc &DL, EVT VT,
                               SDValue Operand, const SDNodeFlags Flags) {
   // Constant fold unary operations with an integer constant operand. Even
   // opaque constant will be folded, because the folding of unary operations
   // doesn't create new constants with different values. Nevertheless, the
   // opaque flag is preserved during folding to prevent future folding with
   // other constants.
   if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Operand)) {
     const APInt &Val = C->getAPIntValue();
     switch (Opcode) {
     default: break;
     case ISD::SIGN_EXTEND:
       return getConstant(Val.sextOrTrunc(VT.getSizeInBits()), DL, VT,
                          C->isTargetOpcode(), C->isOpaque());
     case ISD::TRUNCATE:
       if (C->isOpaque())
         break;

   CSEMap.InsertNode(N, IP);
   InsertNode(N);
 
   SDValue V(N, 0);
   NewSDValueDbgMsg(V, "Creating new node: ", this);
   return V;
 }
 
+SDValue SelectionDAG::getNode(unsigned Opcode, const SDLoc &DL, EVT VT,
+                              SDValue N1, SDValue N2) {
+  SDNodeFlags Flags;
+  if (Inserter)
+    Flags = Inserter->getFlags();
+  return getNode(Opcode, DL, VT, N1, N2, Flags);
+}
+
 SDValue SelectionDAG::getNode(unsigned Opcode, const SDLoc &DL, EVT VT,
                               SDValue N1, SDValue N2, const SDNodeFlags Flags) {
   ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
   ConstantSDNode *N2C = dyn_cast<ConstantSDNode>(N2);
   ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1);
   ConstantFPSDNode *N2CFP = dyn_cast<ConstantFPSDNode>(N2);
 
   // Canonicalize constant to RHS if commutative.

   }
 
   InsertNode(N);
   SDValue V = SDValue(N, 0);
   NewSDValueDbgMsg(V, "Creating new node: ", this);
   return V;
 }
 
+SDValue SelectionDAG::getNode(unsigned Opcode, const SDLoc &DL, EVT VT,
+                              SDValue N1, SDValue N2, SDValue N3) {
+  SDNodeFlags Flags;
+  if (Inserter)
+    Flags = Inserter->getFlags();
+  return getNode(Opcode, DL, VT, N1, N2, N3, Flags);
+}
+
 SDValue SelectionDAG::getNode(unsigned Opcode, const SDLoc &DL, EVT VT,
                               SDValue N1, SDValue N2, SDValue N3,
                               const SDNodeFlags Flags) {
   // Perform various simplifications.
   switch (Opcode) {
   case ISD::FMA: {
     assert(VT.isFloatingPoint() && "This operator only applies to FP types!");
     assert(N1.getValueType() == VT && N2.getValueType() == VT &&

   }
 
   // Copy from an SDUse array into an SDValue array for use with
   // the regular getNode logic.
   SmallVector<SDValue, 8> NewOps(Ops.begin(), Ops.end());
   return getNode(Opcode, DL, VT, NewOps);
 }
 
+SDValue SelectionDAG::getNode(unsigned Opcode, const SDLoc &DL, EVT VT,
+                              ArrayRef<SDValue> Ops) {
+  SDNodeFlags Flags;
+  if (Inserter)
+    Flags = Inserter->getFlags();
+  return getNode(Opcode, DL, VT, Ops, Flags);
+}
+
 SDValue SelectionDAG::getNode(unsigned Opcode, const SDLoc &DL, EVT VT,
                               ArrayRef<SDValue> Ops, const SDNodeFlags Flags) {
   unsigned NumOps = Ops.size();
   switch (NumOps) {
   case 0: return getNode(Opcode, DL, VT);
   case 1: return getNode(Opcode, DL, VT, Ops[0], Flags);
   case 2: return getNode(Opcode, DL, VT, Ops[0], Ops[1], Flags);
   case 3: return getNode(Opcode, DL, VT, Ops[0], Ops[1], Ops[2], Flags);

   return V;
 }
 
 SDValue SelectionDAG::getNode(unsigned Opcode, const SDLoc &DL,
                               ArrayRef<EVT> ResultTys, ArrayRef<SDValue> Ops) {
   return getNode(Opcode, DL, getVTList(ResultTys), Ops);
 }
 
+SDValue SelectionDAG::getNode(unsigned Opcode, const SDLoc &DL, SDVTList VTList,
+                              ArrayRef<SDValue> Ops) {
+  SDNodeFlags Flags;
+  if (Inserter)
+    Flags = Inserter->getFlags();
+  return getNode(Opcode, DL, VTList, Ops, Flags);
+}
+
 SDValue SelectionDAG::getNode(unsigned Opcode, const SDLoc &DL, SDVTList VTList,
                               ArrayRef<SDValue> Ops, const SDNodeFlags Flags) {
   if (VTList.NumVTs == 1)
     return getNode(Opcode, DL, VTList.VTs[0], Ops);
 
   switch (Opcode) {
   case ISD::STRICT_FP_EXTEND:
     assert(VTList.NumVTs == 2 && Ops.size() == 2 &&

   SDValue SRIdxVal = getTargetConstant(SRIdx, DL, MVT::i32);
   SDNode *Result = getMachineNode(TargetOpcode::INSERT_SUBREG, DL,
                                   VT, Operand, Subreg, SRIdxVal);
   return SDValue(Result, 0);
 }
 
 /// getNodeIfExists - Get the specified node if it's already available, or
 /// else return NULL.
+SDNode *SelectionDAG::getNodeIfExists(unsigned Opcode, SDVTList VTList,
+                                      ArrayRef<SDValue> Ops) {
+  SDNodeFlags Flags;
+  if (Inserter)
+    Flags = Inserter->getFlags();
+  return getNodeIfExists(Opcode, VTList, Ops, Flags);
+}
+
 SDNode *SelectionDAG::getNodeIfExists(unsigned Opcode, SDVTList VTList,
                                       ArrayRef<SDValue> Ops,
                                       const SDNodeFlags Flags) {
   if (VTList.VTs[VTList.NumVTs - 1] != MVT::Glue) {
     FoldingSetNodeID ID;
     AddNodeIDNode(ID, Opcode, VTList, Ops);
     void *IP = nullptr;
     if (SDNode *E = FindNodeOrInsertPos(ID, SDLoc(), IP)) {

llvm/test/CodeGen/X86/sqrt-fastmath-mir.ll

 }
 
 define float @sqrt_ieee_ninf(float %f) #0 {
   ; CHECK-LABEL: name: sqrt_ieee_ninf
   ; CHECK: bb.0 (%ir-block.0):
   ; CHECK:   liveins: $xmm0
   ; CHECK:   [[COPY:%[0-9]+]]:fr32 = COPY $xmm0
   ; CHECK:   [[DEF:%[0-9]+]]:fr32 = IMPLICIT_DEF
-  ; CHECK:   [[VRSQRTSSr:%[0-9]+]]:fr32 = VRSQRTSSr killed [[DEF]], [[COPY]]
+  ; CHECK:   [[VRSQRTSSr:%[0-9]+]]:fr32 = ninf VRSQRTSSr killed [[DEF]], [[COPY]]
   ; CHECK:   %3:fr32 = ninf nofpexcept VMULSSrr [[COPY]], [[VRSQRTSSr]], implicit $mxcsr
   ; CHECK:   [[VMOVSSrm_alt:%[0-9]+]]:fr32 = VMOVSSrm_alt $rip, 1, $noreg, %const.0, $noreg :: (load 4 from constant-pool)
   ; CHECK:   %5:fr32 = ninf nofpexcept VFMADD213SSr [[VRSQRTSSr]], killed %3, [[VMOVSSrm_alt]], implicit $mxcsr
   ; CHECK:   [[VMOVSSrm_alt1:%[0-9]+]]:fr32 = VMOVSSrm_alt $rip, 1, $noreg, %const.1, $noreg :: (load 4 from constant-pool)
   ; CHECK:   %7:fr32 = ninf nofpexcept VMULSSrr [[VRSQRTSSr]], [[VMOVSSrm_alt1]], implicit $mxcsr
   ; CHECK:   %8:fr32 = ninf nofpexcept VMULSSrr killed %7, killed %5, implicit $mxcsr
   ; CHECK:   %9:fr32 = ninf nofpexcept VMULSSrr [[COPY]], %8, implicit $mxcsr
   ; CHECK:   %10:fr32 = ninf nofpexcept VFMADD213SSr %8, %9, [[VMOVSSrm_alt]], implicit $mxcsr

 }
 
 define float @sqrt_daz_ninf(float %f) #1 {
   ; CHECK-LABEL: name: sqrt_daz_ninf
   ; CHECK: bb.0 (%ir-block.0):
   ; CHECK:   liveins: $xmm0
   ; CHECK:   [[COPY:%[0-9]+]]:fr32 = COPY $xmm0
   ; CHECK:   [[DEF:%[0-9]+]]:fr32 = IMPLICIT_DEF
-  ; CHECK:   [[VRSQRTSSr:%[0-9]+]]:fr32 = VRSQRTSSr killed [[DEF]], [[COPY]]
+  ; CHECK:   [[VRSQRTSSr:%[0-9]+]]:fr32 = ninf VRSQRTSSr killed [[DEF]], [[COPY]]
   ; CHECK:   %3:fr32 = ninf nofpexcept VMULSSrr [[COPY]], [[VRSQRTSSr]], implicit $mxcsr
   ; CHECK:   [[VMOVSSrm_alt:%[0-9]+]]:fr32 = VMOVSSrm_alt $rip, 1, $noreg, %const.0, $noreg :: (load 4 from constant-pool)
   ; CHECK:   %5:fr32 = ninf nofpexcept VFMADD213SSr [[VRSQRTSSr]], killed %3, [[VMOVSSrm_alt]], implicit $mxcsr
   ; CHECK:   [[VMOVSSrm_alt1:%[0-9]+]]:fr32 = VMOVSSrm_alt $rip, 1, $noreg, %const.1, $noreg :: (load 4 from constant-pool)
   ; CHECK:   %7:fr32 = ninf nofpexcept VMULSSrr [[VRSQRTSSr]], [[VMOVSSrm_alt1]], implicit $mxcsr
   ; CHECK:   %8:fr32 = ninf nofpexcept VMULSSrr killed %7, killed %5, implicit $mxcsr
   ; CHECK:   %9:fr32 = ninf nofpexcept VMULSSrr [[COPY]], %8, implicit $mxcsr
   ; CHECK:   %10:fr32 = ninf nofpexcept VFMADD213SSr %8, %9, [[VMOVSSrm_alt]], implicit $mxcsr

 }
 
 define float @rsqrt_ieee(float %f) #0 {
   ; CHECK-LABEL: name: rsqrt_ieee
   ; CHECK: bb.0 (%ir-block.0):
   ; CHECK:   liveins: $xmm0
   ; CHECK:   [[COPY:%[0-9]+]]:fr32 = COPY $xmm0
   ; CHECK:   [[DEF:%[0-9]+]]:fr32 = IMPLICIT_DEF
-  ; CHECK:   [[VRSQRTSSr:%[0-9]+]]:fr32 = VRSQRTSSr killed [[DEF]], [[COPY]]
+  ; CHECK:   [[VRSQRTSSr:%[0-9]+]]:fr32 = nnan ninf nsz arcp contract afn reassoc VRSQRTSSr killed [[DEF]], [[COPY]]
   ; CHECK:   %3:fr32 = nnan ninf nsz arcp contract afn reassoc nofpexcept VMULSSrr [[COPY]], [[VRSQRTSSr]], implicit $mxcsr
   ; CHECK:   [[VMOVSSrm_alt:%[0-9]+]]:fr32 = VMOVSSrm_alt $rip, 1, $noreg, %const.0, $noreg :: (load 4 from constant-pool)
   ; CHECK:   %5:fr32 = nnan ninf nsz arcp contract afn reassoc nofpexcept VFMADD213SSr [[VRSQRTSSr]], killed %3, [[VMOVSSrm_alt]], implicit $mxcsr
   ; CHECK:   [[VMOVSSrm_alt1:%[0-9]+]]:fr32 = VMOVSSrm_alt $rip, 1, $noreg, %const.1, $noreg :: (load 4 from constant-pool)
   ; CHECK:   %7:fr32 = nnan ninf nsz arcp contract afn reassoc nofpexcept VMULSSrr [[VRSQRTSSr]], [[VMOVSSrm_alt1]], implicit $mxcsr
   ; CHECK:   %8:fr32 = nnan ninf nsz arcp contract afn reassoc nofpexcept VMULSSrr killed %7, killed %5, implicit $mxcsr
   ; CHECK:   %9:fr32 = nnan ninf nsz arcp contract afn reassoc nofpexcept VMULSSrr [[COPY]], %8, implicit $mxcsr
   ; CHECK:   %10:fr32 = nnan ninf nsz arcp contract afn reassoc nofpexcept VFMADD213SSr %8, killed %9, [[VMOVSSrm_alt]], implicit $mxcsr
   ; CHECK:   %11:fr32 = nnan ninf nsz arcp contract afn reassoc nofpexcept VMULSSrr %8, [[VMOVSSrm_alt1]], implicit $mxcsr
   ; CHECK:   %12:fr32 = nnan ninf nsz arcp contract afn reassoc nofpexcept VMULSSrr killed %11, killed %10, implicit $mxcsr
   ; CHECK:   $xmm0 = COPY %12
   ; CHECK:   RET 0, $xmm0
   %sqrt = tail call float @llvm.sqrt.f32(float %f)
   %div = fdiv fast float 1.0, %sqrt
   ret float %div
 }
 
 define float @rsqrt_daz(float %f) #1 {
   ; CHECK-LABEL: name: rsqrt_daz
   ; CHECK: bb.0 (%ir-block.0):
   ; CHECK:   liveins: $xmm0
   ; CHECK:   [[COPY:%[0-9]+]]:fr32 = COPY $xmm0
   ; CHECK:   [[DEF:%[0-9]+]]:fr32 = IMPLICIT_DEF
-  ; CHECK:   [[VRSQRTSSr:%[0-9]+]]:fr32 = VRSQRTSSr killed [[DEF]], [[COPY]]
+  ; CHECK:   [[VRSQRTSSr:%[0-9]+]]:fr32 = nnan ninf nsz arcp contract afn reassoc VRSQRTSSr killed [[DEF]], [[COPY]]
   ; CHECK:   %3:fr32 = nnan ninf nsz arcp contract afn reassoc nofpexcept VMULSSrr [[COPY]], [[VRSQRTSSr]], implicit $mxcsr
   ; CHECK:   [[VMOVSSrm_alt:%[0-9]+]]:fr32 = VMOVSSrm_alt $rip, 1, $noreg, %const.0, $noreg :: (load 4 from constant-pool)
   ; CHECK:   %5:fr32 = nnan ninf nsz arcp contract afn reassoc nofpexcept VFMADD213SSr [[VRSQRTSSr]], killed %3, [[VMOVSSrm_alt]], implicit $mxcsr
   ; CHECK:   [[VMOVSSrm_alt1:%[0-9]+]]:fr32 = VMOVSSrm_alt $rip, 1, $noreg, %const.1, $noreg :: (load 4 from constant-pool)
   ; CHECK:   %7:fr32 = nnan ninf nsz arcp contract afn reassoc nofpexcept VMULSSrr [[VRSQRTSSr]], [[VMOVSSrm_alt1]], implicit $mxcsr
   ; CHECK:   %8:fr32 = nnan ninf nsz arcp contract afn reassoc nofpexcept VMULSSrr killed %7, killed %5, implicit $mxcsr
   ; CHECK:   %9:fr32 = nnan ninf nsz arcp contract afn reassoc nofpexcept VMULSSrr [[COPY]], %8, implicit $mxcsr
   ; CHECK:   %10:fr32 = nnan ninf nsz arcp contract afn reassoc nofpexcept VFMADD213SSr %8, killed %9, [[VMOVSSrm_alt]], implicit $mxcsr