diff --git a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
index 49bf813..101e8eb 100644
--- a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -651,6 +651,9 @@
   std::pair<GlobalValue::GUID, GlobalValue::GUID>
 
   getGUIDFromValueId(unsigned ValueId);
+  std::pair<GlobalValue::GUID, CalleeInfo::HotnessType>
+  readCallGraphEdge(const SmallVector<uint64_t, 64> &Record, unsigned int &I,
+                    bool IsOldProfileFormat, bool HasProfile);
 };
 
 } // end anonymous namespace
@@ -6218,8 +6221,10 @@
       return error("Invalid Summary Block: version expected");
   }
   const uint64_t Version = Record[0];
-  if (Version != 1)
-    return error("Invalid summary version " + Twine(Version) + ", 1 expected");
+  const bool IsOldProfileFormat = Version == 1;
+  if (!IsOldProfileFormat && Version != 2)
+    return error("Invalid summary version " + Twine(Version) +
+                 ", 1 or 2 expected");
   Record.clear();
 
   // Keep around the last seen summary to be used when we see an optional
@@ -6264,10 +6269,10 @@
     default: // Default behavior: ignore.
       break;
     // FS_PERMODULE: [valueid, flags, instcount, numrefs, numrefs x valueid,
-    //                n x (valueid, callsitecount)]
+    //                n x (valueid)]
     // FS_PERMODULE_PROFILE: [valueid, flags, instcount, numrefs,
     //                        numrefs x valueid,
-    //                        n x (valueid, callsitecount, profilecount)]
+    //                        n x (valueid, hotness)]
     case bitc::FS_PERMODULE:
     case bitc::FS_PERMODULE_PROFILE: {
       unsigned ValueID = Record[0];
@@ -6296,12 +6301,11 @@
       bool HasProfile = (BitCode == bitc::FS_PERMODULE_PROFILE);
       for (unsigned I = CallGraphEdgeStartIndex, E = Record.size(); I != E;
            ++I) {
-        unsigned CalleeValueId = Record[I];
-        unsigned CallsiteCount = Record[++I];
-        uint64_t ProfileCount = HasProfile ? Record[++I] : 0;
-        GlobalValue::GUID CalleeGUID = getGUIDFromValueId(CalleeValueId).first;
-        FS->addCallGraphEdge(CalleeGUID,
-                             CalleeInfo(CallsiteCount, ProfileCount));
+        CalleeInfo::HotnessType Hotness;
+        GlobalValue::GUID CalleeGUID;
+        std::tie(CalleeGUID, Hotness) =
+            readCallGraphEdge(Record, I, IsOldProfileFormat, HasProfile);
+        FS->addCallGraphEdge(CalleeGUID, CalleeInfo(Hotness));
       }
       auto GUID = getGUIDFromValueId(ValueID);
       FS->setOriginalName(GUID.second);
@@ -6356,10 +6360,9 @@
       break;
     }
     // FS_COMBINED: [valueid, modid, flags, instcount, numrefs,
-    //               numrefs x valueid, n x (valueid, callsitecount)]
+    //               numrefs x valueid, n x (valueid)]
     // FS_COMBINED_PROFILE: [valueid, modid, flags, instcount, numrefs,
-    //                       numrefs x valueid,
-    //                       n x (valueid, callsitecount, profilecount)]
+    //                       numrefs x valueid, n x (valueid, hotness)]
     case bitc::FS_COMBINED:
     case bitc::FS_COMBINED_PROFILE: {
       unsigned ValueID = Record[0];
@@ -6385,12 +6388,11 @@
       bool HasProfile = (BitCode == bitc::FS_COMBINED_PROFILE);
       for (unsigned I = CallGraphEdgeStartIndex, E = Record.size(); I != E;
            ++I) {
-        unsigned CalleeValueId = Record[I];
-        unsigned CallsiteCount = Record[++I];
-        uint64_t ProfileCount = HasProfile ? Record[++I] : 0;
-        GlobalValue::GUID CalleeGUID = getGUIDFromValueId(CalleeValueId).first;
-        FS->addCallGraphEdge(CalleeGUID,
-                             CalleeInfo(CallsiteCount, ProfileCount));
+        CalleeInfo::HotnessType Hotness;
+        GlobalValue::GUID CalleeGUID;
+        std::tie(CalleeGUID, Hotness) =
+            readCallGraphEdge(Record, I, IsOldProfileFormat, HasProfile);
+        FS->addCallGraphEdge(CalleeGUID, CalleeInfo(Hotness));
       }
       GlobalValue::GUID GUID = getGUIDFromValueId(ValueID).first;
       TheIndex->addGlobalValueSummary(GUID, std::move(FS));
@@ -6456,6 +6458,23 @@
   llvm_unreachable("Exit infinite loop");
 }
 
+std::pair<GlobalValue::GUID, CalleeInfo::HotnessType>
+ModuleSummaryIndexBitcodeReader::readCallGraphEdge(
+    const SmallVector<uint64_t, 64> &Record, unsigned int &I,
+    const bool IsOldProfileFormat, const bool HasProfile) {
+
+  auto Hotness = CalleeInfo::HotnessType::Unknown;
+  unsigned CalleeValueId = Record[I];
+  GlobalValue::GUID CalleeGUID = getGUIDFromValueId(CalleeValueId).first;
+  if (IsOldProfileFormat) {
+    I += 1; // Skip old callsitecount field
+    if (HasProfile)
+      I += 1; // Skip old profilecount field
+  } else if (HasProfile)
+    Hotness = static_cast<CalleeInfo::HotnessType>(Record[++I]);
+  return {CalleeGUID, Hotness};
+}
+
 // Parse the  module string table block into the Index.
 // This populates the ModulePathStringTable map in the index.
 std::error_code ModuleSummaryIndexBitcodeReader::parseModuleStringTable() {