3 files changed, 47 insertions, 1 deletions
diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
index d3aea37f944..24ddfb9585c 100644
--- a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
@@ -4532,6 +4532,24 @@ void SelectionDAGLegalize::PromoteNode(SDNode *Node) {
     Results.push_back(CvtVec);
     break;
   }
+  case ISD::ATOMIC_SWAP: {
+    AtomicSDNode *AM = cast<AtomicSDNode>(Node);
+    SDLoc SL(Node);
+    SDValue CastVal = DAG.getNode(ISD::BITCAST, SL, NVT, AM->getVal());
+    assert(NVT.getSizeInBits() == OVT.getSizeInBits() &&
+           "unexpected promotion type");
+    assert(AM->getMemoryVT().getSizeInBits() == NVT.getSizeInBits() &&
+           "unexpected atomic_swap with illegal type");
+
+    SDValue NewAtomic
+      = DAG.getAtomic(ISD::ATOMIC_SWAP, SL, NVT,
+                      DAG.getVTList(NVT, MVT::Other),
+                      { AM->getChain(), AM->getBasePtr(), CastVal },
+                      AM->getMemOperand());
+    Results.push_back(DAG.getNode(ISD::BITCAST, SL, OVT, NewAtomic));
+    Results.push_back(NewAtomic.getValue(1));
+    break;
+  }
   }
 
   // Replace the original node with the legalized result.
diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeFloatTypes.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeFloatTypes.cpp
index 4644e9588e7..f08526fb0ef 100644
--- a/llvm/lib/CodeGen/SelectionDAG/LegalizeFloatTypes.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeFloatTypes.cpp
@@ -104,6 +104,7 @@ bool DAGTypeLegalizer::SoftenFloatResult(SDNode *N, unsigned ResNo) {
     case ISD::FSUB:        R = SoftenFloatRes_FSUB(N); break;
     case ISD::FTRUNC:      R = SoftenFloatRes_FTRUNC(N); break;
     case ISD::LOAD:        R = SoftenFloatRes_LOAD(N, ResNo); break;
+    case ISD::ATOMIC_SWAP: R = BitcastToInt_ATOMIC_SWAP(N); break;
     case ISD::SELECT:      R = SoftenFloatRes_SELECT(N, ResNo); break;
     case ISD::SELECT_CC:   R = SoftenFloatRes_SELECT_CC(N, ResNo); break;
     case ISD::SINT_TO_FP:
@@ -1932,7 +1933,7 @@ void DAGTypeLegalizer::PromoteFloatResult(SDNode *N, unsigned ResNo) {
     case ISD::SINT_TO_FP:
     case ISD::UINT_TO_FP: R = PromoteFloatRes_XINT_TO_FP(N); break;
     case ISD::UNDEF:      R = PromoteFloatRes_UNDEF(N); break;
-
+    case ISD::ATOMIC_SWAP: R = BitcastToInt_ATOMIC_SWAP(N); break;
   }
 
   if (R.getNode())
@@ -2166,3 +2167,29 @@ SDValue DAGTypeLegalizer::PromoteFloatRes_UNDEF(SDNode *N) {
                                                N->getValueType(0)));
 }
 
+SDValue DAGTypeLegalizer::BitcastToInt_ATOMIC_SWAP(SDNode *N) {
+  EVT VT = N->getValueType(0);
+  EVT NFPVT = TLI.getTypeToTransformTo(*DAG.getContext(), VT);
+
+  AtomicSDNode *AM = cast<AtomicSDNode>(N);
+  SDLoc SL(N);
+
+  SDValue CastVal = BitConvertToInteger(AM->getVal());
+  EVT CastVT = CastVal.getValueType();
+
+  SDValue NewAtomic
+    = DAG.getAtomic(ISD::ATOMIC_SWAP, SL, CastVT,
+                    DAG.getVTList(CastVT, MVT::Other),
+                    { AM->getChain(), AM->getBasePtr(), CastVal },
+                    AM->getMemOperand());
+
+  SDValue ResultCast = DAG.getNode(GetPromotionOpcode(VT, NFPVT), SL, NFPVT,
+                                   NewAtomic);
+  // Legalize the chain result by replacing uses of the old value chain with the
+  // new one
+  ReplaceValueWith(SDValue(N, 1), NewAtomic.getValue(1));
+
+  return ResultCast;
+
+}
+
diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeTypes.h b/llvm/lib/CodeGen/SelectionDAG/LegalizeTypes.h
index 032000f6cb7..737d9bd9634 100644
--- a/llvm/lib/CodeGen/SelectionDAG/LegalizeTypes.h
+++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeTypes.h
@@ -640,6 +640,7 @@ private:
   SDValue PromoteFloatRes_SELECT_CC(SDNode *N);
   SDValue PromoteFloatRes_UnaryOp(SDNode *N);
   SDValue PromoteFloatRes_UNDEF(SDNode *N);
+  SDValue BitcastToInt_ATOMIC_SWAP(SDNode *N);
   SDValue PromoteFloatRes_XINT_TO_FP(SDNode *N);
 
   bool PromoteFloatOperand(SDNode *N, unsigned OpNo);