[PDB] Move PDB functions to a separate file.

We are going to use the hash functions from TPI streams.

Differential Revision: http://reviews.llvm.org/D21142

llvm-svn: 272223

include/llvm/DebugInfo/PDB/Raw/Hash.h

@@ -0,0 +1,22 @@
+//===- Hash.h - PDB hash functions ------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_DEBUGINFO_PDB_RAW_HASH_H
+#define LLVM_DEBUGINFO_PDB_RAW_HASH_H
+
+#include "llvm/ADT/StringRef.h"
+
+namespace llvm {
+namespace pdb {
+uint32_t HashStringV1(StringRef Str);
+uint32_t HashStringV2(StringRef Str);
+}
+}
+
+#endif

lib/DebugInfo/PDB/CMakeLists.txt

@@ -30,6 +30,7 @@ endif()
 add_pdb_impl_folder(Raw
   Raw/DbiStream.cpp
   Raw/EnumTables.cpp
+  Raw/Hash.cpp
   Raw/IndexedStreamData.cpp
   Raw/InfoStream.cpp
   Raw/MappedBlockStream.cpp

lib/DebugInfo/PDB/Raw/Hash.cpp

@@ -0,0 +1,77 @@
+//===- Hash.cpp - PDB Hash Functions --------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/DebugInfo/PDB/Raw/Hash.h"
+
+#include "llvm/ADT/ArrayRef.h"
+#include "llvm/Support/Endian.h"
+
+using namespace llvm;
+using namespace llvm::support;
+
+// Corresponds to `Hasher::lhashPbCb` in PDB/include/misc.h.
+// Used for name hash table and TPI/IPI hashes.
+uint32_t pdb::HashStringV1(StringRef Str) {
+  uint32_t Result = 0;
+  uint32_t Size = Str.size();
+
+  ArrayRef<ulittle32_t> Longs(reinterpret_cast<const ulittle32_t *>(Str.data()),
+                              Size / 4);
+
+  for (auto Value : Longs)
+    Result ^= Value;
+
+  const uint8_t *Remainder = reinterpret_cast<const uint8_t *>(Longs.end());
+  uint32_t RemainderSize = Size % 4;
+
+  // Maximum of 3 bytes left.  Hash a 2 byte word if possible, then hash the
+  // possibly remaining 1 byte.
+  if (RemainderSize >= 2) {
+    uint16_t Value = *reinterpret_cast<const ulittle16_t *>(Remainder);
+    Result ^= static_cast<uint32_t>(Value);
+    Remainder += 2;
+    RemainderSize -= 2;
+  }
+
+  // hash possible odd byte
+  if (RemainderSize == 1) {
+    Result ^= *(Remainder++);
+  }
+
+  const uint32_t toLowerMask = 0x20202020;
+  Result |= toLowerMask;
+  Result ^= (Result >> 11);
+
+  return Result ^ (Result >> 16);
+}
+
+// Corresponds to `HasherV2::HashULONG` in PDB/include/misc.h.
+// Used for name hash table.
+uint32_t pdb::HashStringV2(StringRef Str) {
+  uint32_t Hash = 0xb170a1bf;
+
+  ArrayRef<char> Buffer(Str.begin(), Str.end());
+
+  ArrayRef<ulittle32_t> Items(
+      reinterpret_cast<const ulittle32_t *>(Buffer.data()),
+      Buffer.size() / sizeof(ulittle32_t));
+  for (ulittle32_t Item : Items) {
+    Hash += Item;
+    Hash += (Hash << 10);
+    Hash ^= (Hash >> 6);
+  }
+  Buffer = Buffer.slice(Items.size() * sizeof(ulittle32_t));
+  for (uint8_t Item : Buffer) {
+    Hash += Item;
+    Hash += (Hash << 10);
+    Hash ^= (Hash >> 6);
+  }
+
+  return Hash * 1664525L + 1013904223L;
+}

lib/DebugInfo/PDB/Raw/NameHashTable.cpp

@@ -11,6 +11,7 @@
 
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/DebugInfo/CodeView/StreamReader.h"
+#include "llvm/DebugInfo/PDB/Raw/Hash.h"
 #include "llvm/DebugInfo/PDB/Raw/RawError.h"
 #include "llvm/Support/Endian.h"
 
@@ -18,65 +19,6 @@ using namespace llvm;
 using namespace llvm::support;
 using namespace llvm::pdb;
 
-// Corresponds to `Hasher::lhashPbCb` in PDB/include/misc.h.
-static inline uint32_t HashStringV1(StringRef Str) {
-  uint32_t Result = 0;
-  uint32_t Size = Str.size();
-
-  ArrayRef<ulittle32_t> Longs(reinterpret_cast<const ulittle32_t *>(Str.data()),
-                              Size / 4);
-
-  for (auto Value : Longs)
-    Result ^= Value;
-
-  const uint8_t *Remainder = reinterpret_cast<const uint8_t *>(Longs.end());
-  uint32_t RemainderSize = Size - Longs.size() * 4;
-
-  // Maximum of 3 bytes left.  Hash a 2 byte word if possible, then hash the
-  // possibly remaining 1 byte.
-  if (RemainderSize >= 2) {
-    uint16_t Value = *reinterpret_cast<const ulittle16_t *>(Remainder);
-    Result ^= static_cast<uint32_t>(Value);
-    Remainder += 2;
-    RemainderSize -= 2;
-  }
-
-  // hash possible odd byte
-  if (RemainderSize == 1) {
-    Result ^= *(Remainder++);
-  }
-
-  const uint32_t toLowerMask = 0x20202020;
-  Result |= toLowerMask;
-  Result ^= (Result >> 11);
-
-  return Result ^ (Result >> 16);
-}
-
-// Corresponds to `HasherV2::HashULONG` in PDB/include/misc.h.
-static inline uint32_t HashStringV2(StringRef Str) {
-  uint32_t Hash = 0xb170a1bf;
-
-  ArrayRef<char> Buffer(Str.begin(), Str.end());
-
-  ArrayRef<ulittle32_t> Items(
-      reinterpret_cast<const ulittle32_t *>(Buffer.data()),
-      Buffer.size() / sizeof(ulittle32_t));
-  for (ulittle32_t Item : Items) {
-    Hash += Item;
-    Hash += (Hash << 10);
-    Hash ^= (Hash >> 6);
-  }
-  Buffer = Buffer.slice(Items.size() * sizeof(ulittle32_t));
-  for (uint8_t Item : Buffer) {
-    Hash += Item;
-    Hash += (Hash << 10);
-    Hash ^= (Hash >> 6);
-  }
-
-  return Hash * 1664525L + 1013904223L;
-}
-
 NameHashTable::NameHashTable() : Signature(0), HashVersion(0), NameCount(0) {}
 
 Error NameHashTable::load(codeview::StreamReader &Stream) {