diff --git a/llvm/include/llvm/ProfileData/SampleProfReader.h b/llvm/include/llvm/ProfileData/SampleProfReader.h
--- a/llvm/include/llvm/ProfileData/SampleProfReader.h
+++ b/llvm/include/llvm/ProfileData/SampleProfReader.h
@@ -657,6 +657,13 @@
   /// Read a string indirectly via the name table.
   ErrorOr<StringRef> readStringFromTable();
 
+  /// Read a context indirectly via the CSNameTable.
+  ErrorOr<SampleContextFrames> readContextFromTable();
+
+  /// Read a context indirectly via the CSNameTable if the profile has context,
+  /// otherwise same as readStringFromTable.
+  ErrorOr<SampleContext> readSampleContextFromTable();
+
   /// Points to the current location in the buffer.
   const uint8_t *Data = nullptr;
 
@@ -678,7 +685,9 @@
   /// The starting address of NameTable containing fixed length MD5.
   const uint8_t *MD5NameMemStart = nullptr;
 
-  virtual ErrorOr<SampleContext> readSampleContextFromTable();
+  /// CSNameTable is used to save full context vectors. It is the backing buffer
+  /// for SampleContextFrames.
+  std::vector<SampleContextFrameVector> CSNameTable;
 
 private:
   std::error_code readSummaryEntry(std::vector<ProfileSummaryEntry> &Entries);
@@ -746,8 +755,6 @@
                                          const SecHdrTableEntry &Entry);
   // placeholder for subclasses to dispatch their own section readers.
   virtual std::error_code readCustomSection(const SecHdrTableEntry &Entry) = 0;
-  ErrorOr<SampleContext> readSampleContextFromTable() override;
-  ErrorOr<SampleContextFrames> readContextFromTable();
 
   std::unique_ptr<ProfileSymbolList> ProfSymList;
 
@@ -762,10 +769,6 @@
   /// The set containing the functions to use when compiling a module.
   DenseSet<StringRef> FuncsToUse;
 
-  /// CSNameTable is used to save full context vectors. This serves as an
-  /// underlying immutable buffer for all clients.
-  std::unique_ptr<const std::vector<SampleContextFrameVector>> CSNameTable;
-
   /// If SkipFlatProf is true, skip the sections with
   /// SecFlagFlat flag.
   bool SkipFlatProf = false;
diff --git a/llvm/lib/ProfileData/SampleProfReader.cpp b/llvm/lib/ProfileData/SampleProfReader.cpp
--- a/llvm/lib/ProfileData/SampleProfReader.cpp
+++ b/llvm/lib/ProfileData/SampleProfReader.cpp
@@ -546,11 +546,27 @@
   return SR;
 }
 
-ErrorOr<SampleContext> SampleProfileReaderBinary::readSampleContextFromTable() {
-  auto FName(readStringFromTable());
-  if (std::error_code EC = FName.getError())
+ErrorOr<SampleContextFrames> SampleProfileReaderBinary::readContextFromTable() {
+  auto ContextIdx = readNumber<size_t>();
+  if (std::error_code EC = ContextIdx.getError())
     return EC;
-  return SampleContext(*FName);
+  if (*ContextIdx >= CSNameTable.size())
+    return sampleprof_error::truncated_name_table;
+  return CSNameTable[*ContextIdx];
+}
+
+ErrorOr<SampleContext> SampleProfileReaderBinary::readSampleContextFromTable() {
+  if (ProfileIsCS) {
+    auto FContext(readContextFromTable());
+    if (std::error_code EC = FContext.getError())
+      return EC;
+    return SampleContext(*FContext);
+  } else {
+    auto FName(readStringFromTable());
+    if (std::error_code EC = FName.getError())
+      return EC;
+    return SampleContext(*FName);
+  }
 }
 
 std::error_code
@@ -671,31 +687,6 @@
   return sampleprof_error::success;
 }
 
-ErrorOr<SampleContextFrames>
-SampleProfileReaderExtBinaryBase::readContextFromTable() {
-  auto ContextIdx = readNumber<size_t>();
-  if (std::error_code EC = ContextIdx.getError())
-    return EC;
-  if (*ContextIdx >= CSNameTable->size())
-    return sampleprof_error::truncated_name_table;
-  return (*CSNameTable)[*ContextIdx];
-}
-
-ErrorOr<SampleContext>
-SampleProfileReaderExtBinaryBase::readSampleContextFromTable() {
-  if (ProfileIsCS) {
-    auto FContext(readContextFromTable());
-    if (std::error_code EC = FContext.getError())
-      return EC;
-    return SampleContext(*FContext);
-  } else {
-    auto FName(readStringFromTable());
-    if (std::error_code EC = FName.getError())
-      return EC;
-    return SampleContext(*FName);
-  }
-}
-
 std::error_code SampleProfileReaderExtBinaryBase::readOneSection(
     const uint8_t *Start, uint64_t Size, const SecHdrTableEntry &Entry) {
   Data = Start;
@@ -1035,7 +1026,7 @@
 SampleProfileReaderExtBinaryBase::readNameTableSec(bool IsMD5,
                                                    bool FixedLengthMD5) {
   if (FixedLengthMD5) {
-    if (IsMD5)
+    if (!IsMD5)
       errs() << "If FixedLengthMD5 is true, UseMD5 has to be true";
     auto Size = readNumber<size_t>();
     if (std::error_code EC = Size.getError())
@@ -1089,11 +1080,10 @@
   if (std::error_code EC = Size.getError())
     return EC;
 
-  std::vector<SampleContextFrameVector> *PNameVec =
-      new std::vector<SampleContextFrameVector>();
-  PNameVec->reserve(*Size);
+  CSNameTable.clear();
+  CSNameTable.reserve(*Size);
   for (size_t I = 0; I < *Size; ++I) {
-    PNameVec->emplace_back(SampleContextFrameVector());
+    CSNameTable.emplace_back(SampleContextFrameVector());
     auto ContextSize = readNumber<uint32_t>();
     if (std::error_code EC = ContextSize.getError())
       return EC;
@@ -1112,18 +1102,15 @@
       if (std::error_code EC = Discriminator.getError())
         return EC;
 
-      PNameVec->back().emplace_back(
+      CSNameTable.back().emplace_back(
           FName.get(), LineLocation(LineOffset.get(), Discriminator.get()));
     }
   }
 
-  // From this point the underlying object of CSNameTable should be immutable.
-  CSNameTable.reset(PNameVec);
   return sampleprof_error::success;
 }
 
 std::error_code
-
 SampleProfileReaderExtBinaryBase::readFuncMetadata(bool ProfileHasAttribute,
                                                    FunctionSamples *FProfile) {
   if (Data < End) {