NFC:  Rename (PDB) RawSession to NativeSession

This eliminates one overload on the term Raw.

Differential Revision: https://reviews.llvm.org/D29098

llvm-svn: 293104
diff --git a/llvm/lib/DebugInfo/PDB/Native/GSI.h b/llvm/lib/DebugInfo/PDB/Native/GSI.h
new file mode 100644
index 0000000..d5f2fb1
--- /dev/null
+++ b/llvm/lib/DebugInfo/PDB/Native/GSI.h
@@ -0,0 +1,70 @@
+//===- GSI.h - Common Declarations for GlobalsStream and PublicsStream ----===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// The data structures defined in this file are based on the reference
+// implementation which is available at
+// https://github.com/Microsoft/microsoft-pdb/blob/master/PDB/dbi/gsi.h
+//
+// When you are reading the reference source code, you'd find the
+// information below useful.
+//
+//  - ppdb1->m_fMinimalDbgInfo seems to be always true.
+//  - SMALLBUCKETS macro is defined.
+//
+// The reference doesn't compile, so I learned just by reading code.
+// It's not guaranteed to be correct.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIB_DEBUGINFO_PDB_RAW_GSI_H
+#define LLVM_LIB_DEBUGINFO_PDB_RAW_GSI_H
+
+#include "llvm/DebugInfo/MSF/StreamArray.h"
+#include "llvm/DebugInfo/PDB/Native/RawTypes.h"
+
+#include "llvm/Support/Endian.h"
+#include "llvm/Support/Error.h"
+
+namespace llvm {
+
+namespace msf {
+class StreamReader;
+}
+
+namespace pdb {
+
+/// From https://github.com/Microsoft/microsoft-pdb/blob/master/PDB/dbi/gsi.cpp
+static const unsigned IPHR_HASH = 4096;
+
+/// Header of the hash tables found in the globals and publics sections.
+/// Based on GSIHashHeader in
+/// https://github.com/Microsoft/microsoft-pdb/blob/master/PDB/dbi/gsi.h
+struct GSIHashHeader {
+  enum : unsigned {
+    HdrSignature = ~0U,
+    HdrVersion = 0xeffe0000 + 19990810,
+  };
+  support::ulittle32_t VerSignature;
+  support::ulittle32_t VerHdr;
+  support::ulittle32_t HrSize;
+  support::ulittle32_t NumBuckets;
+};
+
+Error readGSIHashBuckets(
+    msf::FixedStreamArray<support::ulittle32_t> &HashBuckets,
+    const GSIHashHeader *HashHdr, msf::StreamReader &Reader);
+Error readGSIHashHeader(const GSIHashHeader *&HashHdr,
+                        msf::StreamReader &Reader);
+Error readGSIHashRecords(msf::FixedStreamArray<PSHashRecord> &HashRecords,
+                         const GSIHashHeader *HashHdr,
+                         msf::StreamReader &Reader);
+}
+}
+
+#endif