3 files changed, 52 insertions, 5 deletions
diff --git a/llvm/lib/DebugInfo/CodeView/LazyRandomTypeCollection.cpp b/llvm/lib/DebugInfo/CodeView/LazyRandomTypeCollection.cpp
index 9ba45fd0519..bad291e8381 100644
--- a/llvm/lib/DebugInfo/CodeView/LazyRandomTypeCollection.cpp
+++ b/llvm/lib/DebugInfo/CodeView/LazyRandomTypeCollection.cpp
@@ -90,6 +90,16 @@ CVType LazyRandomTypeCollection::getType(TypeIndex Index) {
   return Records[Index.toArrayIndex()].Type;
 }
 
+Optional<CVType> LazyRandomTypeCollection::tryGetType(TypeIndex Index) {
+  if (auto EC = ensureTypeExists(Index)) {
+    consumeError(std::move(EC));
+    return None;
+  }
+
+  assert(contains(Index));
+  return Records[Index.toArrayIndex()].Type;
+}
+
 StringRef LazyRandomTypeCollection::getTypeName(TypeIndex Index) {
   if (Index.isNoneType() || Index.isSimple())
     return TypeIndex::simpleTypeName(Index);
@@ -113,6 +123,9 @@ StringRef LazyRandomTypeCollection::getTypeName(TypeIndex Index) {
 }
 
 bool LazyRandomTypeCollection::contains(TypeIndex Index) {
+  if (Index.isSimple() || Index.isNoneType())
+    return false;
+
   if (Records.size() <= Index.toArrayIndex())
     return false;
   if (!Records[Index.toArrayIndex()].Type.valid())
diff --git a/llvm/lib/DebugInfo/CodeView/StringsAndChecksums.cpp b/llvm/lib/DebugInfo/CodeView/StringsAndChecksums.cpp
index 306af1d1ef6..85d9dbb8c7d 100644
--- a/llvm/lib/DebugInfo/CodeView/StringsAndChecksums.cpp
+++ b/llvm/lib/DebugInfo/CodeView/StringsAndChecksums.cpp
@@ -35,14 +35,36 @@ void StringsAndChecksumsRef::initializeStrings(
   assert(SR.kind() == DebugSubsectionKind::StringTable);
   assert(!Strings && "Found a string table even though we already have one!");
 
-  OwnedStrings = llvm::make_unique<DebugStringTableSubsectionRef>();
+  OwnedStrings = std::make_shared<DebugStringTableSubsectionRef>();
   consumeError(OwnedStrings->initialize(SR.getRecordData()));
   Strings = OwnedStrings.get();
 }
 
+void StringsAndChecksumsRef::reset() {
+  resetStrings();
+  resetChecksums();
+}
+
+void StringsAndChecksumsRef::resetStrings() {
+  OwnedStrings.reset();
+  Strings = nullptr;
+}
+
+void StringsAndChecksumsRef::resetChecksums() {
+  OwnedChecksums.reset();
+  Checksums = nullptr;
+}
+
+void StringsAndChecksumsRef::setStrings(
+    const DebugStringTableSubsectionRef &StringsRef) {
+  OwnedStrings = std::make_shared<DebugStringTableSubsectionRef>();
+  *OwnedStrings = StringsRef;
+  Strings = OwnedStrings.get();
+}
+
 void StringsAndChecksumsRef::setChecksums(
     const DebugChecksumsSubsectionRef &CS) {
-  OwnedChecksums = llvm::make_unique<DebugChecksumsSubsectionRef>();
+  OwnedChecksums = std::make_shared<DebugChecksumsSubsectionRef>();
   *OwnedChecksums = CS;
   Checksums = OwnedChecksums.get();
 }
@@ -53,7 +75,7 @@ void StringsAndChecksumsRef::initializeChecksums(
   if (Checksums)
     return;
 
-  OwnedChecksums = llvm::make_unique<DebugChecksumsSubsectionRef>();
+  OwnedChecksums = std::make_shared<DebugChecksumsSubsectionRef>();
   consumeError(OwnedChecksums->initialize(FCR.getRecordData()));
   Checksums = OwnedChecksums.get();
 }
diff --git a/llvm/lib/DebugInfo/PDB/Native/PDBFile.cpp b/llvm/lib/DebugInfo/PDB/Native/PDBFile.cpp
index 414de7be91f..15b31d821b1 100644
--- a/llvm/lib/DebugInfo/PDB/Native/PDBFile.cpp
+++ b/llvm/lib/DebugInfo/PDB/Native/PDBFile.cpp
@@ -312,6 +312,9 @@ Expected<TpiStream &> PDBFile::getPDBTpiStream() {
 
 Expected<TpiStream &> PDBFile::getPDBIpiStream() {
   if (!Ipi) {
+    if (!hasPDBIpiStream())
+      return make_error<RawError>(raw_error_code::no_stream);
+
     auto IpiS = safelyCreateIndexedStream(ContainerLayout, *Buffer, StreamIPI);
     if (!IpiS)
       return IpiS.takeError();
@@ -407,9 +410,18 @@ bool PDBFile::hasPDBGlobalsStream() {
   return DbiS->getGlobalSymbolStreamIndex() < getNumStreams();
 }
 
-bool PDBFile::hasPDBInfoStream() { return StreamPDB < getNumStreams(); }
+bool PDBFile::hasPDBInfoStream() const { return StreamPDB < getNumStreams(); }
+
+bool PDBFile::hasPDBIpiStream() const {
+  if (!hasPDBInfoStream())
+    return false;
+
+  if (StreamIPI >= getNumStreams())
+    return false;
 
-bool PDBFile::hasPDBIpiStream() const { return StreamIPI < getNumStreams(); }
+  auto &InfoStream = cantFail(const_cast<PDBFile *>(this)->getPDBInfoStream());
+  return InfoStream.containsIdStream();
+}
 
 bool PDBFile::hasPDBPublicsStream() {
   auto DbiS = getPDBDbiStream();