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llvm-svn: 271597
diff --git a/llvm/lib/DebugInfo/PDB/Raw/TpiStream.cpp b/llvm/lib/DebugInfo/PDB/Raw/TpiStream.cpp
index 28c3d64..74a0427 100644
--- a/llvm/lib/DebugInfo/PDB/Raw/TpiStream.cpp
+++ b/llvm/lib/DebugInfo/PDB/Raw/TpiStream.cpp
@@ -35,6 +35,7 @@
   return 0;
 }
 
+// This corresponds to `HDR` in PDB/dbi/tpi.h.
 struct TpiStream::HeaderInfo {
   struct EmbeddedBuf {
     little32_t Off;
@@ -47,6 +48,7 @@
   ulittle32_t TypeIndexEnd;
   ulittle32_t TypeRecordBytes;
 
+  // The following members correspond to `TpiHash` in PDB/dbi/tpi.h.
   ulittle16_t HashStreamIndex;
   ulittle16_t HashAuxStreamIndex;
   ulittle32_t HashKeySize;