diff --git a/llvm/include/llvm/CodeGen/WinEHFuncInfo.h b/llvm/include/llvm/CodeGen/WinEHFuncInfo.h
--- a/llvm/include/llvm/CodeGen/WinEHFuncInfo.h
+++ b/llvm/include/llvm/CodeGen/WinEHFuncInfo.h
@@ -116,7 +116,7 @@
 /// describes the state numbers and tables used by __CxxFrameHandler3. This
 /// analysis assumes that WinEHPrepare has already been run.
 void calculateWinCXXEHStateNumbers(const Function *ParentFn,
-                                   WinEHFuncInfo &FuncInfo);
+                                   WinEHFuncInfo &FuncInfo, bool Is64Bit);
 
 void calculateSEHStateNumbers(const Function *ParentFn,
                               WinEHFuncInfo &FuncInfo);
diff --git a/llvm/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp b/llvm/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp
--- a/llvm/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp
@@ -103,8 +103,9 @@
   if (isFuncletEHPersonality(Personality)) {
     // Calculate state numbers if we haven't already.
     WinEHFuncInfo &EHInfo = *MF->getWinEHFuncInfo();
+    Triple::ArchType Arch = MF->getSubtarget().getTargetTriple().getArch();
     if (Personality == EHPersonality::MSVC_CXX)
-      calculateWinCXXEHStateNumbers(&fn, EHInfo);
+      calculateWinCXXEHStateNumbers(&fn, EHInfo, Arch == Triple::x86_64);
     else if (isAsynchronousEHPersonality(Personality))
       calculateSEHStateNumbers(&fn, EHInfo);
     else if (Personality == EHPersonality::CoreCLR)
diff --git a/llvm/lib/CodeGen/WinEHPrepare.cpp b/llvm/lib/CodeGen/WinEHPrepare.cpp
--- a/llvm/lib/CodeGen/WinEHPrepare.cpp
+++ b/llvm/lib/CodeGen/WinEHPrepare.cpp
@@ -137,9 +137,9 @@
   return FuncInfo.getLastStateNumber();
 }
 
-static void addTryBlockMapEntry(WinEHFuncInfo &FuncInfo, int TryLow,
-                                int TryHigh, int CatchHigh,
-                                ArrayRef<const CatchPadInst *> Handlers) {
+static WinEHTryBlockMapEntry*
+addTryBlockMapEntry(WinEHFuncInfo &FuncInfo, int TryLow, int TryHigh,
+                    int CatchHigh, ArrayRef<const CatchPadInst *> Handlers) {
   WinEHTryBlockMapEntry TBME;
   TBME.TryLow = TryLow;
   TBME.TryHigh = TryHigh;
@@ -162,6 +162,7 @@
     TBME.HandlerArray.push_back(HT);
   }
   FuncInfo.TryBlockMap.push_back(TBME);
+  return &FuncInfo.TryBlockMap.back();
 }
 
 static BasicBlock *getCleanupRetUnwindDest(const CleanupPadInst *CleanupPad) {
@@ -239,7 +240,7 @@
 //      FuncInfo.EHPadStateMap[] and FuncInfo.CxxUnwindMap[]
 static void calculateCXXStateNumbers(WinEHFuncInfo &FuncInfo,
                                      const Instruction *FirstNonPHI,
-                                     int ParentState) {
+                                     int ParentState, bool Is64Bit) {
   const BasicBlock *BB = FirstNonPHI->getParent();
   assert(BB->isEHPad() && "not a funclet!");
 
@@ -258,11 +259,14 @@
       if ((PredBlock = getEHPadFromPredecessor(PredBlock,
                                                CatchSwitch->getParentPad())))
         calculateCXXStateNumbers(FuncInfo, PredBlock->getFirstNonPHI(),
-                                 TryLow);
+                                 TryLow, Is64Bit);
     int CatchLow = addUnwindMapEntry(FuncInfo, ParentState, nullptr);
 
     // catchpads are separate funclets in C++ EH due to the way rethrow works.
     int TryHigh = CatchLow - 1;
+    WinEHTryBlockMapEntry *TBME = nullptr;
+    if (Is64Bit)
+      TBME = addTryBlockMapEntry(FuncInfo, TryLow, TryHigh, 0, Handlers);
     for (const auto *CatchPad : Handlers) {
       FuncInfo.FuncletBaseStateMap[CatchPad] = CatchLow;
       for (const User *U : CatchPad->users()) {
@@ -270,7 +274,7 @@
         if (auto *InnerCatchSwitch = dyn_cast<CatchSwitchInst>(UserI)) {
           BasicBlock *UnwindDest = InnerCatchSwitch->getUnwindDest();
           if (!UnwindDest || UnwindDest == CatchSwitch->getUnwindDest())
-            calculateCXXStateNumbers(FuncInfo, UserI, CatchLow);
+            calculateCXXStateNumbers(FuncInfo, UserI, CatchLow, Is64Bit);
         }
         if (auto *InnerCleanupPad = dyn_cast<CleanupPadInst>(UserI)) {
           BasicBlock *UnwindDest = getCleanupRetUnwindDest(InnerCleanupPad);
@@ -278,17 +282,21 @@
           // enclosing catch pad doesn't it must be post-dominated by an
           // unreachable instruction.
           if (!UnwindDest || UnwindDest == CatchSwitch->getUnwindDest())
-            calculateCXXStateNumbers(FuncInfo, UserI, CatchLow);
+            calculateCXXStateNumbers(FuncInfo, UserI, CatchLow, Is64Bit);
         }
       }
     }
-    int CatchHigh = FuncInfo.getLastStateNumber();
-    addTryBlockMapEntry(FuncInfo, TryLow, TryHigh, CatchHigh, Handlers);
-    LLVM_DEBUG(dbgs() << "TryLow[" << BB->getName() << "]: " << TryLow << '\n');
-    LLVM_DEBUG(dbgs() << "TryHigh[" << BB->getName() << "]: " << TryHigh
+
+    if (!Is64Bit)
+      TBME = addTryBlockMapEntry(FuncInfo, TryLow, TryHigh, 0, Handlers);
+
+    TBME->CatchHigh = FuncInfo.getLastStateNumber();
+    LLVM_DEBUG(dbgs() << "TryLow[" << BB->getName() << "]: " << TBME->TryLow
                       << '\n');
-    LLVM_DEBUG(dbgs() << "CatchHigh[" << BB->getName() << "]: " << CatchHigh
+    LLVM_DEBUG(dbgs() << "TryHigh[" << BB->getName() << "]: " << TBME->TryHigh
                       << '\n');
+    LLVM_DEBUG(dbgs() << "CatchHigh[" << BB->getName() << "]: "
+                      << TBME->CatchHigh << '\n');
   } else {
     auto *CleanupPad = cast<CleanupPadInst>(FirstNonPHI);
 
@@ -305,7 +313,7 @@
       if ((PredBlock = getEHPadFromPredecessor(PredBlock,
                                                CleanupPad->getParentPad()))) {
         calculateCXXStateNumbers(FuncInfo, PredBlock->getFirstNonPHI(),
-                                 CleanupState);
+                                 CleanupState, Is64Bit);
       }
     }
     for (const User *U : CleanupPad->users()) {
@@ -451,7 +459,8 @@
 }
 
 void llvm::calculateWinCXXEHStateNumbers(const Function *Fn,
-                                         WinEHFuncInfo &FuncInfo) {
+                                         WinEHFuncInfo &FuncInfo,
+                                         bool Is64Bit) {
   // Return if it's already been done.
   if (!FuncInfo.EHPadStateMap.empty())
     return;
@@ -462,7 +471,7 @@
     const Instruction *FirstNonPHI = BB.getFirstNonPHI();
     if (!isTopLevelPadForMSVC(FirstNonPHI))
       continue;
-    calculateCXXStateNumbers(FuncInfo, FirstNonPHI, -1);
+    calculateCXXStateNumbers(FuncInfo, FirstNonPHI, -1, Is64Bit);
   }
 
   calculateStateNumbersForInvokes(Fn, FuncInfo);
diff --git a/llvm/lib/Target/X86/X86WinEHState.cpp b/llvm/lib/Target/X86/X86WinEHState.cpp
--- a/llvm/lib/Target/X86/X86WinEHState.cpp
+++ b/llvm/lib/Target/X86/X86WinEHState.cpp
@@ -644,7 +644,7 @@
   if (isAsynchronousEHPersonality(Personality))
     calculateSEHStateNumbers(&F, FuncInfo);
   else
-    calculateWinCXXEHStateNumbers(&F, FuncInfo);
+    calculateWinCXXEHStateNumbers(&F, FuncInfo, false);
 
   // Iterate all the instructions and emit state number stores.
   DenseMap<BasicBlock *, ColorVector> BlockColors = colorEHFunclets(F);
diff --git a/llvm/test/CodeGen/X86/win-catchpad-nested-cxx.ll b/llvm/test/CodeGen/X86/win-catchpad-nested-cxx.ll
--- a/llvm/test/CodeGen/X86/win-catchpad-nested-cxx.ll
+++ b/llvm/test/CodeGen/X86/win-catchpad-nested-cxx.ll
@@ -62,17 +62,29 @@
 ; EHFlags
 ; CHECK-NEXT: .long   1
 
-; CHECK: $tryMap$try_in_catch:
-; CHECK-NEXT: .long   2
-; CHECK-NEXT: .long   2
-; CHECK-NEXT: .long   3
-; CHECK-NEXT: .long   1
-; CHECK-NEXT: .long   ($handlerMap$0$try_in_catch)
-; CHECK-NEXT: .long   0
-; CHECK-NEXT: .long   0
-; CHECK-NEXT: .long   3
-; CHECK-NEXT: .long   1
-; CHECK-NEXT: .long   ($handlerMap$1$try_in_catch)
+; X86-LABEL: $tryMap$try_in_catch:
+; X86-NEXT: .long   2
+; X86-NEXT: .long   2
+; X86-NEXT: .long   3
+; X86-NEXT: .long   1
+; X86-NEXT: .long   ($handlerMap$0$try_in_catch)
+; X86-NEXT: .long   0
+; X86-NEXT: .long   0
+; X86-NEXT: .long   3
+; X86-NEXT: .long   1
+; X86-NEXT: .long   ($handlerMap$1$try_in_catch)
+
+; X64-LABEL: $tryMap$try_in_catch:
+; X64-NEXT: .long   0
+; X64-NEXT: .long   0
+; X64-NEXT: .long   3
+; X64-NEXT: .long   1
+; X64-NEXT: .long   ($handlerMap$0$try_in_catch)
+; X64-NEXT: .long   2
+; X64-NEXT: .long   2
+; X64-NEXT: .long   3
+; X64-NEXT: .long   1
+; X64-NEXT: .long   ($handlerMap$1$try_in_catch)
 
 ; CHECK: $handlerMap$0$try_in_catch:
 ; CHECK-NEXT:   .long   64