[codeview] Add an extra check for TPI hash values.

This patch adds a function that corresponds to `fUDTAnon`
and use that to compute TPI hash values as the reference does.

llvm-svn: 273139
diff --git a/llvm/lib/DebugInfo/PDB/Raw/TpiStream.cpp b/llvm/lib/DebugInfo/PDB/Raw/TpiStream.cpp
index 00ff6e4..feb6f2b 100644
--- a/llvm/lib/DebugInfo/PDB/Raw/TpiStream.cpp
+++ b/llvm/lib/DebugInfo/PDB/Raw/TpiStream.cpp
@@ -64,6 +64,13 @@
 
 TpiStream::~TpiStream() {}
 
+// Corresponds to `fUDTAnon`.
+template <typename T> static bool isAnonymous(T &Rec) {
+  StringRef Name = Rec.getUniqueName();
+  return Name == "<unnamed-tag>" || Name == "__unnamed" ||
+      Name.endswith("::<unnamed-tag>") || Name.endswith("::__unnamed");
+}
+
 // Computes a hash for a given TPI record.
 template <typename T>
 static uint32_t getTpiHash(T &Rec, const CVRecord<TypeLeafKind> &RawRec) {
@@ -73,10 +80,11 @@
       Opts & static_cast<uint16_t>(ClassOptions::ForwardReference);
   bool Scoped = Opts & static_cast<uint16_t>(ClassOptions::Scoped);
   bool UniqueName = Opts & static_cast<uint16_t>(ClassOptions::HasUniqueName);
+  bool IsAnon = UniqueName && isAnonymous(Rec);
 
-  if (!ForwardRef && !Scoped)
+  if (!ForwardRef && !Scoped && !IsAnon)
     return hashStringV1(Rec.getName());
-  if (!ForwardRef && UniqueName)
+  if (!ForwardRef && UniqueName && !IsAnon)
     return hashStringV1(Rec.getUniqueName());
   return hashBufferV8(RawRec.RawData);
 }