[FPEnv] Add fptosi and fptoui constrained intrinsics.

This implements constrained floating point intrinsics for FP to signed and
unsigned integers.

Quoting from D32319:
The purpose of the constrained intrinsics is to force the optimizer to
respect the restrictions that will be necessary to support things like the
STDC FENV_ACCESS ON pragma without interfering with optimizations when
these restrictions are not needed.

Reviewed by:	Andrew Kaylor, Craig Topper, Hal Finkel, Cameron McInally, Roman Lebedev, Kit Barton
Approved by:	Craig Topper
Differential Revision:	http://reviews.llvm.org/D63782

llvm-svn: 370228

12 files changed, 172 insertions, 14 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
index e1775d5cb53..7ceab40c1a5 100644
--- a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
@@ -236,6 +236,16 @@ public:
     }
     ReplacedNode(Old);
   }
+
+  void ReplaceNodeWithValue(SDValue Old, SDValue New) {
+    LLVM_DEBUG(dbgs() << " ... replacing: "; Old->dump(&DAG);
+               dbgs() << "     with:      "; New->dump(&DAG));
+
+    DAG.ReplaceAllUsesOfValueWith(Old, New);
+    if (UpdatedNodes)
+      UpdatedNodes->insert(New.getNode());
+    ReplacedNode(Old.getNode());
+  }
 };
 
 } // end anonymous namespace
@@ -2880,10 +2890,27 @@ bool SelectionDAGLegalize::ExpandNode(SDNode *Node) {
     if (TLI.expandFP_TO_SINT(Node, Tmp1, DAG))
       Results.push_back(Tmp1);
     break;
+  case ISD::STRICT_FP_TO_SINT:
+    if (TLI.expandFP_TO_SINT(Node, Tmp1, DAG)) {
+      ReplaceNode(Node, Tmp1.getNode());
+      LLVM_DEBUG(dbgs() << "Successfully expanded STRICT_FP_TO_SINT node\n");
+      return true;
+    }
+    break;
   case ISD::FP_TO_UINT:
-    if (TLI.expandFP_TO_UINT(Node, Tmp1, DAG))
+    if (TLI.expandFP_TO_UINT(Node, Tmp1, Tmp2, DAG))
       Results.push_back(Tmp1);
     break;
+  case ISD::STRICT_FP_TO_UINT:
+    if (TLI.expandFP_TO_UINT(Node, Tmp1, Tmp2, DAG)) {
+      // Relink the chain.
+      DAG.ReplaceAllUsesOfValueWith(SDValue(Node,1), Tmp2);
+      // Replace the new UINT result.
+      ReplaceNodeWithValue(SDValue(Node, 0), Tmp1);
+      LLVM_DEBUG(dbgs() << "Successfully expanded STRICT_FP_TO_UINT node\n");
+      return true;
+    }
+    break;
   case ISD::LROUND:
     Results.push_back(ExpandArgFPLibCall(Node, RTLIB::LROUND_F32,
                                          RTLIB::LROUND_F64, RTLIB::LROUND_F80,
diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp
index 5a2d335ca1e..cb8ab110142 100644
--- a/llvm/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp
@@ -112,6 +112,8 @@ void DAGTypeLegalizer::PromoteIntegerResult(SDNode *N, unsigned ResNo) {
   case ISD::ZERO_EXTEND:
   case ISD::ANY_EXTEND:  Res = PromoteIntRes_INT_EXTEND(N); break;
 
+  case ISD::STRICT_FP_TO_SINT:
+  case ISD::STRICT_FP_TO_UINT:
   case ISD::FP_TO_SINT:
   case ISD::FP_TO_UINT:  Res = PromoteIntRes_FP_TO_XINT(N); break;
 
@@ -494,7 +496,20 @@ SDValue DAGTypeLegalizer::PromoteIntRes_FP_TO_XINT(SDNode *N) {
       TLI.isOperationLegalOrCustom(ISD::FP_TO_SINT, NVT))
     NewOpc = ISD::FP_TO_SINT;
 
-  SDValue Res = DAG.getNode(NewOpc, dl, NVT, N->getOperand(0));
+  if (N->getOpcode() == ISD::STRICT_FP_TO_UINT &&
+      !TLI.isOperationLegal(ISD::STRICT_FP_TO_UINT, NVT) &&
+      TLI.isOperationLegalOrCustom(ISD::STRICT_FP_TO_SINT, NVT))
+    NewOpc = ISD::STRICT_FP_TO_SINT;
+
+  SDValue Res;
+  if (N->isStrictFPOpcode()) {
+    Res = DAG.getNode(NewOpc, dl, { NVT, MVT::Other }, 
+                      { N->getOperand(0), N->getOperand(1) });
+    // Legalize the chain result - switch anything that used the old chain to
+    // use the new one.
+    ReplaceValueWith(SDValue(N, 1), Res.getValue(1));
+  } else
+    Res = DAG.getNode(NewOpc, dl, NVT, N->getOperand(0));
 
   // Assert that the converted value fits in the original type.  If it doesn't
   // (eg: because the value being converted is too big), then the result of the
@@ -503,7 +518,8 @@ SDValue DAGTypeLegalizer::PromoteIntRes_FP_TO_XINT(SDNode *N) {
   // NOTE: fp-to-uint to fp-to-sint promotion guarantees zero extend. For example:
   //   before legalization: fp-to-uint16, 65534. -> 0xfffe
   //   after legalization: fp-to-sint32, 65534. -> 0x0000fffe
-  return DAG.getNode(N->getOpcode() == ISD::FP_TO_UINT ?
+  return DAG.getNode((N->getOpcode() == ISD::FP_TO_UINT ||
+                      N->getOpcode() == ISD::STRICT_FP_TO_UINT) ?
                      ISD::AssertZext : ISD::AssertSext, dl, NVT, Res,
                      DAG.getValueType(N->getValueType(0).getScalarType()));
 }
diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeTypes.h b/llvm/lib/CodeGen/SelectionDAG/LegalizeTypes.h
index 1d0f8d07797..4fd04229fc4 100644
--- a/llvm/lib/CodeGen/SelectionDAG/LegalizeTypes.h
+++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeTypes.h
@@ -715,6 +715,7 @@ private:
   bool ScalarizeVectorOperand(SDNode *N, unsigned OpNo);
   SDValue ScalarizeVecOp_BITCAST(SDNode *N);
   SDValue ScalarizeVecOp_UnaryOp(SDNode *N);
+  SDValue ScalarizeVecOp_UnaryOp_StrictFP(SDNode *N);
   SDValue ScalarizeVecOp_CONCAT_VECTORS(SDNode *N);
   SDValue ScalarizeVecOp_EXTRACT_VECTOR_ELT(SDNode *N);
   SDValue ScalarizeVecOp_VSELECT(SDNode *N);
diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeVectorOps.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeVectorOps.cpp
index a892fccc8a1..4b8656805f3 100644
--- a/llvm/lib/CodeGen/SelectionDAG/LegalizeVectorOps.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeVectorOps.cpp
@@ -333,6 +333,8 @@ SDValue VectorLegalizer::LegalizeOp(SDValue Op) {
   case ISD::STRICT_FFLOOR:
   case ISD::STRICT_FROUND:
   case ISD::STRICT_FTRUNC:
+  case ISD::STRICT_FP_TO_SINT:
+  case ISD::STRICT_FP_TO_UINT:
   case ISD::STRICT_FP_ROUND:
   case ISD::STRICT_FP_EXTEND:
     Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
@@ -862,6 +864,8 @@ SDValue VectorLegalizer::Expand(SDValue Op) {
   case ISD::STRICT_FFLOOR:
   case ISD::STRICT_FROUND:
   case ISD::STRICT_FTRUNC:
+  case ISD::STRICT_FP_TO_SINT:
+  case ISD::STRICT_FP_TO_UINT:
     return ExpandStrictFPOp(Op);
   case ISD::VECREDUCE_ADD:
   case ISD::VECREDUCE_MUL:
@@ -1186,9 +1190,13 @@ SDValue VectorLegalizer::ExpandABS(SDValue Op) {
 
 SDValue VectorLegalizer::ExpandFP_TO_UINT(SDValue Op) {
   // Attempt to expand using TargetLowering.
-  SDValue Result;
-  if (TLI.expandFP_TO_UINT(Op.getNode(), Result, DAG))
+  SDValue Result, Chain;
+  if (TLI.expandFP_TO_UINT(Op.getNode(), Result, Chain, DAG)) {
+    if (Op.getNode()->isStrictFPOpcode())
+      // Relink the chain
+      DAG.ReplaceAllUsesOfValueWith(Op.getValue(1), Chain);
     return Result;
+  }
 
   // Otherwise go ahead and unroll.
   return DAG.UnrollVectorOp(Op.getNode());
diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
index 1cfa68a232d..24f7f7edd1f 100644
--- a/llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
@@ -171,6 +171,8 @@ void DAGTypeLegalizer::ScalarizeVectorResult(SDNode *N, unsigned ResNo) {
   case ISD::STRICT_FFLOOR:
   case ISD::STRICT_FROUND:
   case ISD::STRICT_FTRUNC:
+  case ISD::STRICT_FP_TO_SINT:
+  case ISD::STRICT_FP_TO_UINT:
   case ISD::STRICT_FP_EXTEND:
     R = ScalarizeVecRes_StrictFPOp(N);
     break;
@@ -604,6 +606,10 @@ bool DAGTypeLegalizer::ScalarizeVectorOperand(SDNode *N, unsigned OpNo) {
     case ISD::UINT_TO_FP:
       Res = ScalarizeVecOp_UnaryOp(N);
       break;
+    case ISD::STRICT_FP_TO_SINT:
+    case ISD::STRICT_FP_TO_UINT:
+      Res = ScalarizeVecOp_UnaryOp_StrictFP(N);
+      break;
     case ISD::CONCAT_VECTORS:
       Res = ScalarizeVecOp_CONCAT_VECTORS(N);
       break;
@@ -679,6 +685,23 @@ SDValue DAGTypeLegalizer::ScalarizeVecOp_UnaryOp(SDNode *N) {
   return DAG.getNode(ISD::SCALAR_TO_VECTOR, SDLoc(N), N->getValueType(0), Op);
 }
 
+/// If the input is a vector that needs to be scalarized, it must be <1 x ty>.
+/// Do the strict FP operation on the element instead.
+SDValue DAGTypeLegalizer::ScalarizeVecOp_UnaryOp_StrictFP(SDNode *N) {
+  assert(N->getValueType(0).getVectorNumElements() == 1 &&
+         "Unexpected vector type!");
+  SDValue Elt = GetScalarizedVector(N->getOperand(1));
+  SDValue Res = DAG.getNode(N->getOpcode(), SDLoc(N),
+                            { N->getValueType(0).getScalarType(), MVT::Other },
+                            { N->getOperand(0), Elt });
+  // Legalize the chain result - switch anything that used the old chain to
+  // use the new one.
+  ReplaceValueWith(SDValue(N, 1), Res.getValue(1));
+  // Revectorize the result so the types line up with what the uses of this
+  // expression expect.
+  return DAG.getNode(ISD::SCALAR_TO_VECTOR, SDLoc(N), N->getValueType(0), Res);
+}
+
 /// The vectors to concatenate have length one - use a BUILD_VECTOR instead.
 SDValue DAGTypeLegalizer::ScalarizeVecOp_CONCAT_VECTORS(SDNode *N) {
   SmallVector<SDValue, 8> Ops(N->getNumOperands());
@@ -883,7 +906,9 @@ void DAGTypeLegalizer::SplitVectorResult(SDNode *N, unsigned ResNo) {
   case ISD::FP_ROUND:
   case ISD::STRICT_FP_ROUND:
   case ISD::FP_TO_SINT:
+  case ISD::STRICT_FP_TO_SINT:
   case ISD::FP_TO_UINT:
+  case ISD::STRICT_FP_TO_UINT:
   case ISD::FRINT:
   case ISD::FROUND:
   case ISD::FSIN:
@@ -1987,6 +2012,8 @@ bool DAGTypeLegalizer::SplitVectorOperand(SDNode *N, unsigned OpNo) {
       break;
     case ISD::FP_TO_SINT:
     case ISD::FP_TO_UINT:
+    case ISD::STRICT_FP_TO_SINT:
+    case ISD::STRICT_FP_TO_UINT:
     case ISD::CTTZ:
     case ISD::CTLZ:
     case ISD::CTPOP:
@@ -2814,6 +2841,8 @@ void DAGTypeLegalizer::WidenVectorResult(SDNode *N, unsigned ResNo) {
 
   case ISD::STRICT_FP_EXTEND:
   case ISD::STRICT_FP_ROUND:
+  case ISD::STRICT_FP_TO_SINT:
+  case ISD::STRICT_FP_TO_UINT:
     Res = WidenVecRes_Convert_StrictFP(N);
     break;
 
@@ -4129,7 +4158,9 @@ bool DAGTypeLegalizer::WidenVectorOperand(SDNode *N, unsigned OpNo) {
   case ISD::FP_EXTEND:
   case ISD::STRICT_FP_EXTEND:
   case ISD::FP_TO_SINT:
+  case ISD::STRICT_FP_TO_SINT:
   case ISD::FP_TO_UINT:
+  case ISD::STRICT_FP_TO_UINT:
   case ISD::SINT_TO_FP:
   case ISD::UINT_TO_FP:
   case ISD::TRUNCATE:
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index fe3996bdb7d..7a9ef2b327e 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -7778,6 +7778,8 @@ SDNode* SelectionDAG::mutateStrictFPToFP(SDNode *Node) {
   case ISD::STRICT_FTRUNC:     NewOpc = ISD::FTRUNC;     break;
   case ISD::STRICT_FP_ROUND:   NewOpc = ISD::FP_ROUND;   break;
   case ISD::STRICT_FP_EXTEND:  NewOpc = ISD::FP_EXTEND;  break;
+  case ISD::STRICT_FP_TO_SINT: NewOpc = ISD::FP_TO_SINT; break;
+  case ISD::STRICT_FP_TO_UINT: NewOpc = ISD::FP_TO_UINT; break;
   }
 
   assert(Node->getNumValues() == 2 && "Unexpected number of results!");
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index cf438691308..105fb42de61 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -6106,6 +6106,8 @@ void SelectionDAGBuilder::visitIntrinsicCall(const CallInst &I,
   case Intrinsic::experimental_constrained_fdiv:
   case Intrinsic::experimental_constrained_frem:
   case Intrinsic::experimental_constrained_fma:
+  case Intrinsic::experimental_constrained_fptosi:
+  case Intrinsic::experimental_constrained_fptoui:
   case Intrinsic::experimental_constrained_fptrunc:
   case Intrinsic::experimental_constrained_fpext:
   case Intrinsic::experimental_constrained_sqrt:
@@ -6899,6 +6901,12 @@ void SelectionDAGBuilder::visitConstrainedFPIntrinsic(
   case Intrinsic::experimental_constrained_fma:
     Opcode = ISD::STRICT_FMA;
     break;
+  case Intrinsic::experimental_constrained_fptosi:
+    Opcode = ISD::STRICT_FP_TO_SINT;
+    break;
+  case Intrinsic::experimental_constrained_fptoui:
+    Opcode = ISD::STRICT_FP_TO_UINT;
+    break;
   case Intrinsic::experimental_constrained_fptrunc:
     Opcode = ISD::STRICT_FP_ROUND;
     break;
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp
index da3049881d3..ff2e34d5255 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGDumper.cpp
@@ -325,7 +325,9 @@ std::string SDNode::getOperationName(const SelectionDAG *G) const {
   case ISD::SINT_TO_FP:                 return "sint_to_fp";
   case ISD::UINT_TO_FP:                 return "uint_to_fp";
   case ISD::FP_TO_SINT:                 return "fp_to_sint";
+  case ISD::STRICT_FP_TO_SINT:          return "strict_fp_to_sint";
   case ISD::FP_TO_UINT:                 return "fp_to_uint";
+  case ISD::STRICT_FP_TO_UINT:          return "strict_fp_to_uint";
   case ISD::BITCAST:                    return "bitcast";
   case ISD::ADDRSPACECAST:              return "addrspacecast";
   case ISD::FP16_TO_FP:                 return "fp16_to_fp";
diff --git a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
index 6fd90ef3301..8c322df862d 100644
--- a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
@@ -5597,7 +5597,8 @@ bool TargetLowering::expandROT(SDNode *Node, SDValue &Result,
 
 bool TargetLowering::expandFP_TO_SINT(SDNode *Node, SDValue &Result,
                                       SelectionDAG &DAG) const {
-  SDValue Src = Node->getOperand(0);
+  unsigned OpNo = Node->isStrictFPOpcode() ? 1 : 0;
+  SDValue Src = Node->getOperand(OpNo);
   EVT SrcVT = Src.getValueType();
   EVT DstVT = Node->getValueType(0);
   SDLoc dl(SDValue(Node, 0));
@@ -5606,6 +5607,13 @@ bool TargetLowering::expandFP_TO_SINT(SDNode *Node, SDValue &Result,
   if (SrcVT != MVT::f32 || DstVT != MVT::i64)
     return false;
 
+  if (Node->isStrictFPOpcode())
+    // When a NaN is converted to an integer a trap is allowed. We can't
+    // use this expansion here because it would eliminate that trap. Other
+    // traps are also allowed and cannot be eliminated. See 
+    // IEEE 754-2008 sec 5.8.
+    return false;
+
   // Expand f32 -> i64 conversion
   // This algorithm comes from compiler-rt's implementation of fixsfdi:
   // https://github.com/llvm/llvm-project/blob/master/compiler-rt/lib/builtins/fixsfdi.c
@@ -5659,9 +5667,11 @@ bool TargetLowering::expandFP_TO_SINT(SDNode *Node, SDValue &Result,
 }
 
 bool TargetLowering::expandFP_TO_UINT(SDNode *Node, SDValue &Result,
+                                      SDValue &Chain,
                                       SelectionDAG &DAG) const {
   SDLoc dl(SDValue(Node, 0));
-  SDValue Src = Node->getOperand(0);
+  unsigned OpNo = Node->isStrictFPOpcode() ? 1 : 0;
+  SDValue Src = Node->getOperand(OpNo);
 
   EVT SrcVT = Src.getValueType();
   EVT DstVT = Node->getValueType(0);
@@ -5669,7 +5679,9 @@ bool TargetLowering::expandFP_TO_UINT(SDNode *Node, SDValue &Result,
       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), SrcVT);
 
   // Only expand vector types if we have the appropriate vector bit operations.
-  if (DstVT.isVector() && (!isOperationLegalOrCustom(ISD::FP_TO_SINT, DstVT) ||
+  unsigned SIntOpcode = Node->isStrictFPOpcode() ? ISD::STRICT_FP_TO_SINT : 
+                                                   ISD::FP_TO_SINT;
+  if (DstVT.isVector() && (!isOperationLegalOrCustom(SIntOpcode, DstVT) ||
                            !isOperationLegalOrCustomOrPromote(ISD::XOR, SrcVT)))
     return false;
 
@@ -5681,14 +5693,21 @@ bool TargetLowering::expandFP_TO_UINT(SDNode *Node, SDValue &Result,
   APInt SignMask = APInt::getSignMask(DstVT.getScalarSizeInBits());
   if (APFloat::opOverflow &
       APF.convertFromAPInt(SignMask, false, APFloat::rmNearestTiesToEven)) {
-    Result = DAG.getNode(ISD::FP_TO_SINT, dl, DstVT, Src);
+    if (Node->isStrictFPOpcode()) {
+      Result = DAG.getNode(ISD::STRICT_FP_TO_SINT, dl, { DstVT, MVT::Other }, 
+                           { Node->getOperand(0), Src }); 
+      Chain = Result.getValue(1);
+    } else
+      Result = DAG.getNode(ISD::FP_TO_SINT, dl, DstVT, Src);
     return true;
   }
 
   SDValue Cst = DAG.getConstantFP(APF, dl, SrcVT);
   SDValue Sel = DAG.getSetCC(dl, SetCCVT, Src, Cst, ISD::SETLT);
 
-  bool Strict = shouldUseStrictFP_TO_INT(SrcVT, DstVT, /*IsSigned*/ false);
+  bool Strict = Node->isStrictFPOpcode() ||
+                shouldUseStrictFP_TO_INT(SrcVT, DstVT, /*IsSigned*/ false);
+
   if (Strict) {
     // Expand based on maximum range of FP_TO_SINT, if the value exceeds the
     // signmask then offset (the result of which should be fully representable).
@@ -5698,12 +5717,23 @@ bool TargetLowering::expandFP_TO_UINT(SDNode *Node, SDValue &Result,
     // Result = fp_to_sint(Val) ^ Ofs
 
     // TODO: Should any fast-math-flags be set for the FSUB?
-    SDValue Val = DAG.getSelect(dl, SrcVT, Sel, Src,
-                                DAG.getNode(ISD::FSUB, dl, SrcVT, Src, Cst));
+    SDValue SrcBiased;
+    if (Node->isStrictFPOpcode())
+      SrcBiased = DAG.getNode(ISD::STRICT_FSUB, dl, { SrcVT, MVT::Other }, 
+                              { Node->getOperand(0), Src, Cst });
+    else
+      SrcBiased = DAG.getNode(ISD::FSUB, dl, SrcVT, Src, Cst);
+    SDValue Val = DAG.getSelect(dl, SrcVT, Sel, Src, SrcBiased);
     SDValue Ofs = DAG.getSelect(dl, DstVT, Sel, DAG.getConstant(0, dl, DstVT),
                                 DAG.getConstant(SignMask, dl, DstVT));
-    Result = DAG.getNode(ISD::XOR, dl, DstVT,
-                         DAG.getNode(ISD::FP_TO_SINT, dl, DstVT, Val), Ofs);
+    SDValue SInt;
+    if (Node->isStrictFPOpcode()) {
+      SInt = DAG.getNode(ISD::STRICT_FP_TO_SINT, dl, { DstVT, MVT::Other }, 
+                         { SrcBiased.getValue(1), Val });
+      Chain = SInt.getValue(1);
+    } else
+      SInt = DAG.getNode(ISD::FP_TO_SINT, dl, DstVT, Val);
+    Result = DAG.getNode(ISD::XOR, dl, DstVT, SInt, Ofs);
   } else {
     // Expand based on maximum range of FP_TO_SINT:
     // True = fp_to_sint(Src)
diff --git a/llvm/lib/CodeGen/TargetLoweringBase.cpp b/llvm/lib/CodeGen/TargetLoweringBase.cpp
index 40ecef5855d..dcedca7e9fb 100644
--- a/llvm/lib/CodeGen/TargetLoweringBase.cpp
+++ b/llvm/lib/CodeGen/TargetLoweringBase.cpp
@@ -716,6 +716,8 @@ void TargetLoweringBase::initActions() {
     setOperationAction(ISD::STRICT_FMINNUM, VT, Expand);
     setOperationAction(ISD::STRICT_FP_ROUND, VT, Expand);
     setOperationAction(ISD::STRICT_FP_EXTEND, VT, Expand);
+    setOperationAction(ISD::STRICT_FP_TO_SINT, VT, Expand);
+    setOperationAction(ISD::STRICT_FP_TO_UINT, VT, Expand);
 
     // For most targets @llvm.get.dynamic.area.offset just returns 0.
     setOperationAction(ISD::GET_DYNAMIC_AREA_OFFSET, VT, Expand);
diff --git a/llvm/lib/IR/IntrinsicInst.cpp b/llvm/lib/IR/IntrinsicInst.cpp
index b2471128007..a426c9b4df1 100644
--- a/llvm/lib/IR/IntrinsicInst.cpp
+++ b/llvm/lib/IR/IntrinsicInst.cpp
@@ -189,6 +189,8 @@ bool ConstrainedFPIntrinsic::isUnaryOp() const {
   switch (getIntrinsicID()) {
     default:
       return false;
+    case Intrinsic::experimental_constrained_fptosi:
+    case Intrinsic::experimental_constrained_fptoui:
     case Intrinsic::experimental_constrained_fptrunc:
     case Intrinsic::experimental_constrained_fpext:
     case Intrinsic::experimental_constrained_sqrt:
diff --git a/llvm/lib/IR/Verifier.cpp b/llvm/lib/IR/Verifier.cpp
index 0350edb2454..59e404b7953 100644
--- a/llvm/lib/IR/Verifier.cpp
+++ b/llvm/lib/IR/Verifier.cpp
@@ -4282,6 +4282,8 @@ void Verifier::visitIntrinsicCall(Intrinsic::ID ID, CallBase &Call) {
   case Intrinsic::experimental_constrained_fdiv:
   case Intrinsic::experimental_constrained_frem:
   case Intrinsic::experimental_constrained_fma:
+  case Intrinsic::experimental_constrained_fptosi:
+  case Intrinsic::experimental_constrained_fptoui:
   case Intrinsic::experimental_constrained_fptrunc:
   case Intrinsic::experimental_constrained_fpext:
   case Intrinsic::experimental_constrained_sqrt:
@@ -4773,6 +4775,33 @@ void Verifier::visitConstrainedFPIntrinsic(ConstrainedFPIntrinsic &FPI) {
     HasRoundingMD = true;
     break;
 
+  case Intrinsic::experimental_constrained_fptosi:
+  case Intrinsic::experimental_constrained_fptoui: { 
+    Assert((NumOperands == 2),
+           "invalid arguments for constrained FP intrinsic", &FPI);
+    HasExceptionMD = true;
+
+    Value *Operand = FPI.getArgOperand(0);
+    uint64_t NumSrcElem = 0;
+    Assert(Operand->getType()->isFPOrFPVectorTy(),
+           "Intrinsic first argument must be floating point", &FPI);
+    if (auto *OperandT = dyn_cast<VectorType>(Operand->getType())) {
+      NumSrcElem = OperandT->getNumElements();
+    }
+
+    Operand = &FPI;
+    Assert((NumSrcElem > 0) == Operand->getType()->isVectorTy(),
+           "Intrinsic first argument and result disagree on vector use", &FPI);
+    Assert(Operand->getType()->isIntOrIntVectorTy(),
+           "Intrinsic result must be an integer", &FPI);
+    if (auto *OperandT = dyn_cast<VectorType>(Operand->getType())) {
+      Assert(NumSrcElem == OperandT->getNumElements(),
+             "Intrinsic first argument and result vector lengths must be equal",
+             &FPI);
+    }
+  }
+    break;
+
   case Intrinsic::experimental_constrained_fptrunc:
   case Intrinsic::experimental_constrained_fpext: {
     if (FPI.getIntrinsicID() == Intrinsic::experimental_constrained_fptrunc) {