11 files changed, 88 insertions, 123 deletions
diff --git a/llvm/include/llvm/DebugInfo/PDB/Raw/HashTable.h b/llvm/include/llvm/DebugInfo/PDB/Raw/HashTable.h
index d8035501203..793df32858d 100644
--- a/llvm/include/llvm/DebugInfo/PDB/Raw/HashTable.h
+++ b/llvm/include/llvm/DebugInfo/PDB/Raw/HashTable.h
@@ -47,6 +47,8 @@ public:
   uint32_t calculateSerializedLength() const;
   Error commit(msf::StreamWriter &Writer) const;
 
+  void clear();
+
   uint32_t capacity() const;
   uint32_t size() const;
 
diff --git a/llvm/include/llvm/DebugInfo/PDB/Raw/InfoStreamBuilder.h b/llvm/include/llvm/DebugInfo/PDB/Raw/InfoStreamBuilder.h
index ab6a0c33ff0..199249225c7 100644
--- a/llvm/include/llvm/DebugInfo/PDB/Raw/InfoStreamBuilder.h
+++ b/llvm/include/llvm/DebugInfo/PDB/Raw/InfoStreamBuilder.h
@@ -14,7 +14,7 @@
 #include "llvm/Support/Error.h"
 
 #include "llvm/DebugInfo/PDB/PDBTypes.h"
-#include "llvm/DebugInfo/PDB/Raw/NamedStreamMapBuilder.h"
+#include "llvm/DebugInfo/PDB/Raw/NamedStreamMap.h"
 #include "llvm/DebugInfo/PDB/Raw/PDBFile.h"
 #include "llvm/DebugInfo/PDB/Raw/RawConstants.h"
 
@@ -37,9 +37,9 @@ public:
   void setAge(uint32_t A);
   void setGuid(PDB_UniqueId G);
 
-  NamedStreamMapBuilder &getNamedStreamsBuilder();
+  NamedStreamMap &getNamedStreamsBuilder();
 
-  uint32_t calculateSerializedLength() const;
+  uint32_t finalize();
 
   Error finalizeMsfLayout();
 
@@ -54,7 +54,7 @@ private:
   uint32_t Age;
   PDB_UniqueId Guid;
 
-  NamedStreamMapBuilder NamedStreams;
+  NamedStreamMap NamedStreams;
 };
 }
 }
diff --git a/llvm/include/llvm/DebugInfo/PDB/Raw/NamedStreamMap.h b/llvm/include/llvm/DebugInfo/PDB/Raw/NamedStreamMap.h
index 088c53aed84..18b828a4a43 100644
--- a/llvm/include/llvm/DebugInfo/PDB/Raw/NamedStreamMap.h
+++ b/llvm/include/llvm/DebugInfo/PDB/Raw/NamedStreamMap.h
@@ -12,6 +12,7 @@
 
 #include "llvm/ADT/StringMap.h"
 #include "llvm/ADT/StringRef.h"
+#include "llvm/DebugInfo/PDB/Raw/HashTable.h"
 #include "llvm/Support/Error.h"
 #include <cstdint>
 
@@ -23,18 +24,28 @@ class StreamWriter;
 namespace pdb {
 class NamedStreamMapBuilder;
 class NamedStreamMap {
+  struct FinalizationInfo {
+    uint32_t StringDataBytes = 0;
+    uint32_t SerializedLength = 0;
+  };
   friend NamedStreamMapBuilder;
 
 public:
   NamedStreamMap();
 
   Error load(msf::StreamReader &Stream);
+  Error commit(msf::StreamWriter &Writer) const;
+  uint32_t finalize();
 
-  bool tryGetValue(StringRef Name, uint32_t &Value) const;
+  bool get(StringRef Stream, uint32_t &StreamNo) const;
+  void set(StringRef Stream, uint32_t StreamNo);
+  void remove(StringRef Stream);
 
   iterator_range<StringMapConstIterator<uint32_t>> entries() const;
 
 private:
+  Optional<FinalizationInfo> FinalizedInfo;
+  HashTable FinalizedHashTable;
   StringMap<uint32_t> Mapping;
 };
 
diff --git a/llvm/include/llvm/DebugInfo/PDB/Raw/NamedStreamMapBuilder.h b/llvm/include/llvm/DebugInfo/PDB/Raw/NamedStreamMapBuilder.h
deleted file mode 100644
index b53a60dd426..00000000000
--- a/llvm/include/llvm/DebugInfo/PDB/Raw/NamedStreamMapBuilder.h
+++ /dev/null
@@ -1,45 +0,0 @@
-//===- NamedStreamMapBuilder.h - PDB Named Stream Map Builder ---*- 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_PDBNAMEDSTREAMMAPBUILDER_H
-#define LLVM_DEBUGINFO_PDB_RAW_PDBNAMEDSTREAMMAPBUILDER_H
-
-#include "llvm/DebugInfo/PDB/Raw/HashTable.h"
-#include "llvm/Support/Error.h"
-
-#include <cstdint>
-#include <memory>
-#include <vector>
-
-namespace llvm {
-namespace msf {
-class StreamWriter;
-}
-namespace pdb {
-
-class NamedStreamMapBuilder {
-public:
-  NamedStreamMapBuilder();
-
-  void addMapping(StringRef Name, uint32_t Mapping);
-
-  Error commit(msf::StreamWriter &Writer) const;
-
-  uint32_t calculateSerializedLength() const;
-
-private:
-  std::vector<StringRef> Strings;
-  HashTable Map;
-  uint32_t Offset = 0;
-};
-
-} // end namespace pdb
-} // end namespace llvm
-
-#endif // LLVM_DEBUGINFO_PDB_RAW_PDBNAMEMAPBUILDER_H
diff --git a/llvm/lib/DebugInfo/PDB/CMakeLists.txt b/llvm/lib/DebugInfo/PDB/CMakeLists.txt
index 469886d23e8..1a995e6b351 100644
--- a/llvm/lib/DebugInfo/PDB/CMakeLists.txt
+++ b/llvm/lib/DebugInfo/PDB/CMakeLists.txt
@@ -40,7 +40,6 @@ add_pdb_impl_folder(Raw
   Raw/ModInfo.cpp
   Raw/ModStream.cpp
   Raw/NamedStreamMap.cpp
-  Raw/NamedStreamMapBuilder.cpp
   Raw/PDBFile.cpp
   Raw/PDBFileBuilder.cpp
   Raw/PublicsStream.cpp
diff --git a/llvm/lib/DebugInfo/PDB/Raw/HashTable.cpp b/llvm/lib/DebugInfo/PDB/Raw/HashTable.cpp
index b218f3d8f38..aadc13e53a5 100644
--- a/llvm/lib/DebugInfo/PDB/Raw/HashTable.cpp
+++ b/llvm/lib/DebugInfo/PDB/Raw/HashTable.cpp
@@ -99,6 +99,12 @@ Error HashTable::commit(msf::StreamWriter &Writer) const {
   return Error::success();
 }
 
+void HashTable::clear() {
+  Buckets.resize(8);
+  Present.clear();
+  Deleted.clear();
+}
+
 uint32_t HashTable::capacity() const { return Buckets.size(); }
 uint32_t HashTable::size() const { return Present.count(); }
 
diff --git a/llvm/lib/DebugInfo/PDB/Raw/InfoStream.cpp b/llvm/lib/DebugInfo/PDB/Raw/InfoStream.cpp
index f19535d1180..9334d2a6a23 100644
--- a/llvm/lib/DebugInfo/PDB/Raw/InfoStream.cpp
+++ b/llvm/lib/DebugInfo/PDB/Raw/InfoStream.cpp
@@ -56,7 +56,7 @@ Error InfoStream::reload() {
 
 uint32_t InfoStream::getNamedStreamIndex(llvm::StringRef Name) const {
   uint32_t Result;
-  if (!NamedStreams.tryGetValue(Name, Result))
+  if (!NamedStreams.get(Name, Result))
     return 0;
   return Result;
 }
diff --git a/llvm/lib/DebugInfo/PDB/Raw/InfoStreamBuilder.cpp b/llvm/lib/DebugInfo/PDB/Raw/InfoStreamBuilder.cpp
index 50539658819..4485c83dc05 100644
--- a/llvm/lib/DebugInfo/PDB/Raw/InfoStreamBuilder.cpp
+++ b/llvm/lib/DebugInfo/PDB/Raw/InfoStreamBuilder.cpp
@@ -32,16 +32,12 @@ void InfoStreamBuilder::setAge(uint32_t A) { Age = A; }
 
 void InfoStreamBuilder::setGuid(PDB_UniqueId G) { Guid = G; }
 
-NamedStreamMapBuilder &InfoStreamBuilder::getNamedStreamsBuilder() {
+NamedStreamMap &InfoStreamBuilder::getNamedStreamsBuilder() {
   return NamedStreams;
 }
 
-uint32_t InfoStreamBuilder::calculateSerializedLength() const {
-  return sizeof(InfoStreamHeader) + NamedStreams.calculateSerializedLength();
-}
-
 Error InfoStreamBuilder::finalizeMsfLayout() {
-  uint32_t Length = calculateSerializedLength();
+  uint32_t Length = sizeof(InfoStreamHeader) + NamedStreams.finalize();
   if (auto EC = Msf.setStreamSize(StreamPDB, Length))
     return EC;
   return Error::success();
diff --git a/llvm/lib/DebugInfo/PDB/Raw/NamedStreamMap.cpp b/llvm/lib/DebugInfo/PDB/Raw/NamedStreamMap.cpp
index 77077bc3738..54d2649ac22 100644
--- a/llvm/lib/DebugInfo/PDB/Raw/NamedStreamMap.cpp
+++ b/llvm/lib/DebugInfo/PDB/Raw/NamedStreamMap.cpp
@@ -27,6 +27,10 @@ using namespace llvm::pdb;
 NamedStreamMap::NamedStreamMap() = default;
 
 Error NamedStreamMap::load(StreamReader &Stream) {
+  Mapping.clear();
+  FinalizedHashTable.clear();
+  FinalizedInfo.reset();
+
   uint32_t StringBufferSize;
   if (auto EC = Stream.readInteger(StringBufferSize))
     return joinErrors(std::move(EC),
@@ -63,16 +67,69 @@ Error NamedStreamMap::load(StreamReader &Stream) {
   return Error::success();
 }
 
+Error NamedStreamMap::commit(msf::StreamWriter &Writer) const {
+  assert(FinalizedInfo.hasValue());
+
+  // The first field is the number of bytes of string data.
+  if (auto EC = Writer.writeInteger(
+          FinalizedInfo->StringDataBytes)) // Number of bytes of string data
+    return EC;
+
+  // Now all of the string data itself.
+  for (const auto &Item : Mapping) {
+    if (auto EC = Writer.writeZeroString(Item.getKey()))
+      return EC;
+  }
+
+  // And finally the Offset Index map.
+  if (auto EC = FinalizedHashTable.commit(Writer))
+    return EC;
+
+  return Error::success();
+}
+
+uint32_t NamedStreamMap::finalize() {
+  if (FinalizedInfo.hasValue())
+    return FinalizedInfo->SerializedLength;
+
+  // Build the finalized hash table.
+  FinalizedHashTable.clear();
+  FinalizedInfo.emplace();
+  for (const auto &Item : Mapping) {
+    FinalizedHashTable.set(FinalizedInfo->StringDataBytes, Item.getValue());
+    FinalizedInfo->StringDataBytes += Item.getKeyLength() + 1;
+  }
+
+  // Number of bytes of string data.
+  FinalizedInfo->SerializedLength += sizeof(support::ulittle32_t);
+  // Followed by that many actual bytes of string data.
+  FinalizedInfo->SerializedLength += FinalizedInfo->StringDataBytes;
+  // Followed by the mapping from Offset to Index.
+  FinalizedInfo->SerializedLength +=
+      FinalizedHashTable.calculateSerializedLength();
+  return FinalizedInfo->SerializedLength;
+}
+
 iterator_range<StringMapConstIterator<uint32_t>>
 NamedStreamMap::entries() const {
   return make_range<StringMapConstIterator<uint32_t>>(Mapping.begin(),
                                                       Mapping.end());
 }
 
-bool NamedStreamMap::tryGetValue(StringRef Name, uint32_t &Value) const {
-  auto Iter = Mapping.find(Name);
+bool NamedStreamMap::get(StringRef Stream, uint32_t &StreamNo) const {
+  auto Iter = Mapping.find(Stream);
   if (Iter == Mapping.end())
     return false;
-  Value = Iter->second;
+  StreamNo = Iter->second;
   return true;
 }
+
+void NamedStreamMap::set(StringRef Stream, uint32_t StreamNo) {
+  FinalizedInfo.reset();
+  Mapping[Stream] = StreamNo;
+}
+
+void NamedStreamMap::remove(StringRef Stream) {
+  FinalizedInfo.reset();
+  Mapping.erase(Stream);
+}
diff --git a/llvm/lib/DebugInfo/PDB/Raw/NamedStreamMapBuilder.cpp b/llvm/lib/DebugInfo/PDB/Raw/NamedStreamMapBuilder.cpp
deleted file mode 100644
index 886d2ffb331..00000000000
--- a/llvm/lib/DebugInfo/PDB/Raw/NamedStreamMapBuilder.cpp
+++ /dev/null
@@ -1,60 +0,0 @@
-//===- NamedStreamMapBuilder.cpp - PDB Named Stream Map Builder -*- C++ -*-===//
-//
-//                     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/NamedStreamMapBuilder.h"
-#include "llvm/ADT/STLExtras.h"
-#include "llvm/DebugInfo/MSF/StreamWriter.h"
-#include "llvm/DebugInfo/PDB/Raw/NamedStreamMap.h"
-#include "llvm/Support/Endian.h"
-#include "llvm/Support/Error.h"
-#include <algorithm>
-#include <cstdint>
-
-using namespace llvm;
-using namespace llvm::pdb;
-
-NamedStreamMapBuilder::NamedStreamMapBuilder() = default;
-
-void NamedStreamMapBuilder::addMapping(StringRef Name, uint32_t Mapping) {
-  Strings.push_back(Name);
-  Map.set(Offset, Mapping);
-  Offset += Name.size() + 1;
-}
-
-uint32_t NamedStreamMapBuilder::calculateSerializedLength() const {
-  uint32_t TotalLength = 0;
-
-  // Number of bytes of string data.
-  TotalLength += sizeof(support::ulittle32_t);
-  // Followed by that many actual bytes of string data.
-  TotalLength += Offset;
-  // Followed by the mapping from Name to Index.
-  TotalLength += Map.calculateSerializedLength();
-
-  return TotalLength;
-}
-
-Error NamedStreamMapBuilder::commit(msf::StreamWriter &Writer) const {
-  // The first field is the number of bytes of string data.  We've already been
-  // keeping a running total of this in `Offset`.
-  if (auto EC = Writer.writeInteger(Offset)) // Number of bytes of string data
-    return EC;
-
-  // Now all of the string data itself.
-  for (auto S : Strings) {
-    if (auto EC = Writer.writeZeroString(S))
-      return EC;
-  }
-
-  // And finally the Linear Map.
-  if (auto EC = Map.commit(Writer))
-    return EC;
-
-  return Error::success();
-}
diff --git a/llvm/tools/llvm-pdbdump/llvm-pdbdump.cpp b/llvm/tools/llvm-pdbdump/llvm-pdbdump.cpp
index cce0a043997..762af6d1e5b 100644
--- a/llvm/tools/llvm-pdbdump/llvm-pdbdump.cpp
+++ b/llvm/tools/llvm-pdbdump/llvm-pdbdump.cpp
@@ -352,8 +352,7 @@ static void yamlToPdb(StringRef Path) {
     InfoBuilder.setSignature(YamlObj.PdbStream->Signature);
     InfoBuilder.setVersion(YamlObj.PdbStream->Version);
     for (auto &NM : YamlObj.PdbStream->NamedStreams)
-      InfoBuilder.getNamedStreamsBuilder().addMapping(NM.StreamName,
-                                                      NM.StreamNumber);
+      InfoBuilder.getNamedStreamsBuilder().set(NM.StreamName, NM.StreamNumber);
   }
 
   if (YamlObj.DbiStream.hasValue()) {