Index: llvm/include/llvm/Analysis/TypeMetadataUtils.h
===================================================================
--- llvm/include/llvm/Analysis/TypeMetadataUtils.h
+++ llvm/include/llvm/Analysis/TypeMetadataUtils.h
@@ -32,14 +32,16 @@
 /// call sites based on the call and return them in DevirtCalls.
 void findDevirtualizableCallsForTypeTest(
     SmallVectorImpl<DevirtCallSite> &DevirtCalls,
-    SmallVectorImpl<CallInst *> &Assumes, CallInst *CI);
+    SmallVectorImpl<CallInst *> &Assumes, bool &HasNonAssumeUses,
+    const CallInst *CI);
 
 /// Given a call to the intrinsic @llvm.type.checked.load, find all
 /// devirtualizable call sites based on the call and return them in DevirtCalls.
 void findDevirtualizableCallsForTypeCheckedLoad(
     SmallVectorImpl<DevirtCallSite> &DevirtCalls,
     SmallVectorImpl<Instruction *> &LoadedPtrs,
-    SmallVectorImpl<Instruction *> &Preds, bool &HasNonCallUses, CallInst *CI);
+    SmallVectorImpl<Instruction *> &Preds, bool &HasNonCallUses,
+    const CallInst *CI);
 }
 
 #endif
Index: llvm/include/llvm/Bitcode/LLVMBitCodes.h
===================================================================
--- llvm/include/llvm/Bitcode/LLVMBitCodes.h
+++ llvm/include/llvm/Bitcode/LLVMBitCodes.h
@@ -213,6 +213,8 @@
   FS_COMBINED_ORIGINAL_NAME = 9,
   // VERSION of the summary, bumped when adding flags for instance.
   FS_VERSION = 10,
+  // The list of llvm.type.test type identifiers used by the following function.
+  FS_TYPE_TESTS = 11,
 };
 
 enum MetadataCodes {
Index: llvm/include/llvm/IR/ModuleSummaryIndex.h
===================================================================
--- llvm/include/llvm/IR/ModuleSummaryIndex.h
+++ llvm/include/llvm/IR/ModuleSummaryIndex.h
@@ -284,12 +284,15 @@
   /// List of <CalleeValueInfo, CalleeInfo> call edge pairs from this function.
   OwningArrayRef<EdgeTy> CallGraphEdgeList;
 
+  /// List of type identifiers used by this function, represented as GUIDs.
+  OwningArrayRef<GlobalValue::GUID> TypeIdList;
+
 public:
   /// Summary constructors.
   FunctionSummary(GVFlags Flags, unsigned NumInsts, ArrayRef<ValueInfo> Refs,
-                  ArrayRef<EdgeTy> CGEdges)
+                  ArrayRef<EdgeTy> CGEdges, ArrayRef<GlobalValue::GUID> TypeIds)
       : GlobalValueSummary(FunctionKind, Flags, Refs), InstCount(NumInsts),
-        CallGraphEdgeList(CGEdges) {}
+        CallGraphEdgeList(CGEdges), TypeIdList(TypeIds) {}
 
   /// Check if this is a function summary.
   static bool classof(const GlobalValueSummary *GVS) {
@@ -301,6 +304,9 @@
 
   /// Return the list of <CalleeValueInfo, CalleeInfo> pairs.
   ArrayRef<EdgeTy> calls() const { return CallGraphEdgeList; }
+
+  /// Returns the list of type identifiers used by this function.
+  ArrayRef<GlobalValue::GUID> type_tests() const { return TypeIdList; }
 };
 
 /// \brief Global variable summary information to aid decisions and
Index: llvm/lib/Analysis/ModuleSummaryAnalysis.cpp
===================================================================
--- llvm/lib/Analysis/ModuleSummaryAnalysis.cpp
+++ llvm/lib/Analysis/ModuleSummaryAnalysis.cpp
@@ -22,6 +22,7 @@
 #include "llvm/Analysis/IndirectCallPromotionAnalysis.h"
 #include "llvm/Analysis/LoopInfo.h"
 #include "llvm/Analysis/ProfileSummaryInfo.h"
+#include "llvm/Analysis/TypeMetadataUtils.h"
 #include "llvm/IR/CallSite.h"
 #include "llvm/IR/Dominators.h"
 #include "llvm/IR/InstIterator.h"
@@ -92,6 +93,7 @@
   // counts for all static calls to a given callee.
   MapVector<ValueInfo, CalleeInfo> CallGraphEdges;
   SetVector<ValueInfo> RefEdges;
+  SetVector<GlobalValue::GUID> TypeTests;
   ICallPromotionAnalysis ICallAnalysis;
 
   bool HasInlineAsmMaybeReferencingInternal = false;
@@ -125,9 +127,23 @@
       }
       // Check if this is a direct call to a known function.
       if (CalledFunction) {
-        // Skip intrinsics.
-        if (CalledFunction->isIntrinsic())
+        if (CalledFunction->isIntrinsic()) {
+          // Produce a summary from type.test intrinsics.
+          if (CalledFunction->getIntrinsicID() == Intrinsic::type_test) {
+            SmallVector<DevirtCallSite, 1> DevirtCalls;
+            SmallVector<CallInst *, 1> Assumes;
+            bool HasNonAssumeUses;
+            findDevirtualizableCallsForTypeTest(DevirtCalls, Assumes,
+                                                HasNonAssumeUses, CI);
+            if (HasNonAssumeUses) {
+              auto TypeMDVal = cast<MetadataAsValue>(CI->getArgOperand(1));
+              if (auto *TypeId = dyn_cast<MDString>(TypeMDVal->getMetadata()))
+                TypeTests.insert(GlobalValue::getGUID(TypeId->getString()));
+            }
+          }
+          // Skip all other intrinsics.
           continue;
+        }
         // We should have named any anonymous globals
         assert(CalledFunction->hasName());
         auto ScaledCount = BFI ? BFI->getBlockProfileCount(&BB) : None;
@@ -161,7 +177,8 @@
 
   GlobalValueSummary::GVFlags Flags(F);
   auto FuncSummary = llvm::make_unique<FunctionSummary>(
-      Flags, NumInsts, RefEdges.getArrayRef(), CallGraphEdges.getArrayRef());
+      Flags, NumInsts, RefEdges.getArrayRef(), CallGraphEdges.getArrayRef(),
+      TypeTests.getArrayRef());
   if (HasInlineAsmMaybeReferencingInternal)
     FuncSummary->setHasInlineAsmMaybeReferencingInternal();
   Index.addGlobalValueSummary(F.getName(), std::move(FuncSummary));
@@ -281,7 +298,8 @@
             std::unique_ptr<FunctionSummary> Summary =
                 llvm::make_unique<FunctionSummary>(
                     GVFlags, 0, ArrayRef<ValueInfo>{},
-                    ArrayRef<FunctionSummary::EdgeTy>{});
+                    ArrayRef<FunctionSummary::EdgeTy>{},
+                    ArrayRef<GlobalValue::GUID>{});
             Summary->setNoRename();
             Index.addGlobalValueSummary(Name, std::move(Summary));
           } else {
Index: llvm/lib/Analysis/TypeMetadataUtils.cpp
===================================================================
--- llvm/lib/Analysis/TypeMetadataUtils.cpp
+++ llvm/lib/Analysis/TypeMetadataUtils.cpp
@@ -39,7 +39,7 @@
 
 // Search for virtual calls that load from VPtr and add them to DevirtCalls.
 static void
-findLoadCallsAtConstantOffset(Module *M,
+findLoadCallsAtConstantOffset(const Module *M,
                               SmallVectorImpl<DevirtCallSite> &DevirtCalls,
                               Value *VPtr, int64_t Offset) {
   for (const Use &U : VPtr->uses()) {
@@ -62,10 +62,12 @@
 
 void llvm::findDevirtualizableCallsForTypeTest(
     SmallVectorImpl<DevirtCallSite> &DevirtCalls,
-    SmallVectorImpl<CallInst *> &Assumes, CallInst *CI) {
+    SmallVectorImpl<CallInst *> &Assumes, bool &HasNonAssumeUses,
+    const CallInst *CI) {
   assert(CI->getCalledFunction()->getIntrinsicID() == Intrinsic::type_test);
+  HasNonAssumeUses = false;
 
-  Module *M = CI->getParent()->getParent()->getParent();
+  const Module *M = CI->getParent()->getParent()->getParent();
 
   // Find llvm.assume intrinsics for this llvm.type.test call.
   for (const Use &CIU : CI->uses()) {
@@ -74,6 +76,8 @@
       Function *F = AssumeCI->getCalledFunction();
       if (F && F->getIntrinsicID() == Intrinsic::assume)
         Assumes.push_back(AssumeCI);
+    } else {
+      HasNonAssumeUses = true;
     }
   }
 
@@ -87,7 +91,8 @@
 void llvm::findDevirtualizableCallsForTypeCheckedLoad(
     SmallVectorImpl<DevirtCallSite> &DevirtCalls,
     SmallVectorImpl<Instruction *> &LoadedPtrs,
-    SmallVectorImpl<Instruction *> &Preds, bool &HasNonCallUses, CallInst *CI) {
+    SmallVectorImpl<Instruction *> &Preds, bool &HasNonCallUses,
+    const CallInst *CI) {
   assert(CI->getCalledFunction()->getIntrinsicID() ==
          Intrinsic::type_checked_load);
 
@@ -97,7 +102,7 @@
     return;
   }
 
-  for (Use &U : CI->uses()) {
+  for (const Use &U : CI->uses()) {
     auto CIU = U.getUser();
     if (auto EVI = dyn_cast<ExtractValueInst>(CIU)) {
       if (EVI->getNumIndices() == 1 && EVI->getIndices()[0] == 0) {
Index: llvm/lib/Bitcode/Reader/BitcodeReader.cpp
===================================================================
--- llvm/lib/Bitcode/Reader/BitcodeReader.cpp
+++ llvm/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -4845,6 +4845,7 @@
   // "OriginalName" attachement.
   GlobalValueSummary *LastSeenSummary = nullptr;
   bool Combined = false;
+  std::vector<GlobalValue::GUID> PendingTypeTests;
 
   while (true) {
     BitstreamEntry Entry = Stream.advanceSkippingSubblocks();
@@ -4909,8 +4910,9 @@
       std::vector<FunctionSummary::EdgeTy> Calls = makeCallList(
           ArrayRef<uint64_t>(Record).slice(CallGraphEdgeStartIndex),
           IsOldProfileFormat, HasProfile);
-      auto FS =
-          llvm::make_unique<FunctionSummary>(Flags, InstCount, Refs, Calls);
+      auto FS = llvm::make_unique<FunctionSummary>(Flags, InstCount, Refs,
+                                                   Calls, PendingTypeTests);
+      PendingTypeTests.clear();
       auto GUID = getGUIDFromValueId(ValueID);
       FS->setModulePath(TheIndex.addModulePath(ModulePath, 0)->first());
       FS->setOriginalName(GUID.second);
@@ -4981,8 +4983,9 @@
           ArrayRef<uint64_t>(Record).slice(CallGraphEdgeStartIndex),
           IsOldProfileFormat, HasProfile);
       GlobalValue::GUID GUID = getGUIDFromValueId(ValueID).first;
-      auto FS =
-          llvm::make_unique<FunctionSummary>(Flags, InstCount, Refs, Edges);
+      auto FS = llvm::make_unique<FunctionSummary>(
+          Flags, InstCount, Refs, Edges, PendingTypeTests);
+      PendingTypeTests.clear();
       LastSeenSummary = FS.get();
       FS->setModulePath(ModuleIdMap[ModuleId]);
       TheIndex.addGlobalValueSummary(GUID, std::move(FS));
@@ -5038,6 +5041,12 @@
       LastSeenSummary->setOriginalName(OriginalName);
       // Reset the LastSeenSummary
       LastSeenSummary = nullptr;
+      break;
+    }
+    case bitc::FS_TYPE_TESTS: {
+      PendingTypeTests.insert(PendingTypeTests.end(), Record.begin(),
+                              Record.end());
+      break;
     }
     }
   }
Index: llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
===================================================================
--- llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -3271,6 +3271,9 @@
   NameVals.push_back(ValueID);
 
   FunctionSummary *FS = cast<FunctionSummary>(Summary);
+  if (!FS->type_tests().empty())
+    Stream.EmitRecord(bitc::FS_TYPE_TESTS, FS->type_tests());
+
   NameVals.push_back(getEncodedGVSummaryFlags(FS->flags()));
   NameVals.push_back(FS->instCount());
   NameVals.push_back(FS->refs().size());
@@ -3530,6 +3533,9 @@
     }
 
     auto *FS = cast<FunctionSummary>(S);
+    if (!FS->type_tests().empty())
+      Stream.EmitRecord(bitc::FS_TYPE_TESTS, FS->type_tests());
+
     NameVals.push_back(ValueId);
     NameVals.push_back(Index.getModuleId(FS->modulePath()));
     NameVals.push_back(getEncodedGVSummaryFlags(FS->flags()));
Index: llvm/lib/Transforms/IPO/WholeProgramDevirt.cpp
===================================================================
--- llvm/lib/Transforms/IPO/WholeProgramDevirt.cpp
+++ llvm/lib/Transforms/IPO/WholeProgramDevirt.cpp
@@ -755,7 +755,9 @@
     // Search for virtual calls based on %p and add them to DevirtCalls.
     SmallVector<DevirtCallSite, 1> DevirtCalls;
     SmallVector<CallInst *, 1> Assumes;
-    findDevirtualizableCallsForTypeTest(DevirtCalls, Assumes, CI);
+    bool HasNonAssumeUses;
+    findDevirtualizableCallsForTypeTest(DevirtCalls, Assumes, HasNonAssumeUses,
+                                        CI);
 
     // If we found any, add them to CallSlots. Only do this if we haven't seen
     // the vtable pointer before, as it may have been CSE'd with pointers from
Index: llvm/test/Bitcode/thinlto-type-tests.ll
===================================================================
--- /dev/null
+++ llvm/test/Bitcode/thinlto-type-tests.ll
@@ -0,0 +1,30 @@
+; RUN: opt -module-summary %s -o %t.o
+; RUN: llvm-bcanalyzer -dump %t.o | FileCheck %s
+; RUN: llvm-lto -thinlto -o %t2 %t.o
+; RUN: llvm-bcanalyzer -dump %t2.thinlto.bc | FileCheck --check-prefix=COMBINED %s
+
+; COMBINED: <TYPE_TESTS op0=-2012135647395072713/>
+; COMBINED: <TYPE_TESTS op0=6699318081062747564 op1=-2012135647395072713/>
+; COMBINED: <TYPE_TESTS op0=6699318081062747564/>
+
+; CHECK: <TYPE_TESTS op0=6699318081062747564/>
+define i1 @f() {
+  %p = call i1 @llvm.type.test(i8* null, metadata !"foo")
+  ret i1 %p
+}
+
+; CHECK: <TYPE_TESTS op0=6699318081062747564 op1=-2012135647395072713/>
+define i1 @g() {
+  %p = call i1 @llvm.type.test(i8* null, metadata !"foo")
+  %q = call i1 @llvm.type.test(i8* null, metadata !"bar")
+  %pq = and i1 %p, %q
+  ret i1 %pq
+}
+
+; CHECK: <TYPE_TESTS op0=-2012135647395072713/>
+define i1 @h() {
+  %p = call i1 @llvm.type.test(i8* null, metadata !"bar")
+  ret i1 %p
+}
+
+declare i1 @llvm.type.test(i8*, metadata) nounwind readnone
Index: llvm/tools/llvm-bcanalyzer/llvm-bcanalyzer.cpp
===================================================================
--- llvm/tools/llvm-bcanalyzer/llvm-bcanalyzer.cpp
+++ llvm/tools/llvm-bcanalyzer/llvm-bcanalyzer.cpp
@@ -311,6 +311,7 @@
       STRINGIFY_CODE(FS, COMBINED_ALIAS)
       STRINGIFY_CODE(FS, COMBINED_ORIGINAL_NAME)
       STRINGIFY_CODE(FS, VERSION)
+      STRINGIFY_CODE(FS, TYPE_TESTS)
     }
   case bitc::METADATA_ATTACHMENT_ID:
     switch(CodeID) {