Revert r301986 (and subsequent r301987).

The patch is failing to add StringTableStreamBuilder.h, but that isn't
even discovered because the corresponding StringTableStreamBuilder.cpp
isn't added to any CMakeLists.txt file and thus never built. I think
this patch is just incomplete.

llvm-svn: 302002

include/llvm/DebugInfo/CodeView/StringTable.h

@@ -1,70 +0,0 @@
-//===- StringTable.h - CodeView String Table Reader/Writer ------*- 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_CODEVIEW_STRINGTABLE_H
-#define LLVM_DEBUGINFO_CODEVIEW_STRINGTABLE_H
-
-#include "llvm/ADT/StringMap.h"
-#include "llvm/ADT/StringRef.h"
-
-#include "llvm/Support/BinaryStreamRef.h"
-#include "llvm/Support/Error.h"
-
-#include <stdint.h>
-
-namespace llvm {
-
-class BinaryStreamReader;
-class BinaryStreamRef;
-class BinaryStreamWriter;
-
-namespace codeview {
-
-/// Represents a read-only view of a CodeView string table.  This is a very
-/// simple flat buffer consisting of null-terminated strings, where strings
-/// are retrieved by their offset in the buffer.  StringTableRef does not own
-/// the underlying storage for the buffer.
-class StringTableRef {
-public:
-  StringTableRef();
-
-  Error initialize(BinaryStreamReader &Stream);
-
-  StringRef getString(uint32_t Offset) const;
-
-private:
-  BinaryStreamRef Stream;
-};
-
-/// Represents a read-write view of a CodeView string table.  StringTable owns
-/// the underlying storage for the table, and is capable of serializing the
-/// string table into a format understood by StringTableRef.
-class StringTable {
-public:
-  // If string S does not exist in the string table, insert it.
-  // Returns the ID for S.
-  uint32_t insert(StringRef S);
-
-  uint32_t calculateSerializedSize() const;
-  Error commit(BinaryStreamWriter &Writer) const;
-
-  uint32_t size() const;
-
-  StringMap<uint32_t>::const_iterator begin() const { return Strings.begin(); }
-
-  StringMap<uint32_t>::const_iterator end() const { return Strings.end(); }
-
-private:
-  StringMap<uint32_t> Strings;
-  uint32_t StringSize = 1;
-};
-}
-}
-
-#endif

include/llvm/DebugInfo/PDB/Native/PDBFile.h

@@ -130,7 +130,7 @@ private:
   std::unique_ptr<PublicsStream> Publics;
   std::unique_ptr<SymbolStream> Symbols;
   std::unique_ptr<msf::MappedBlockStream> DirectoryStream;
-  std::unique_ptr<msf::MappedBlockStream> StringTableStream;
+  std::unique_ptr<msf::MappedBlockStream> PDBStringTableStream;
   std::unique_ptr<PDBStringTable> Strings;
 };
 }

include/llvm/DebugInfo/PDB/Native/PDBFileBuilder.h

@@ -50,10 +50,8 @@ public:
 
   Error commit(StringRef Filename);
 
-  Expected<uint32_t> getNamedStreamIndex(StringRef Name) const;
-  Error addNamedStream(StringRef Name, uint32_t Size);
-
 private:
+  Error addNamedStream(StringRef Name, uint32_t Size);
   Expected<msf::MSFLayout> finalizeMsfLayout();
 
   BumpPtrAllocator &Allocator;

include/llvm/DebugInfo/PDB/Native/PDBStringTable.h

@@ -13,7 +13,6 @@
 
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/StringRef.h"
-#include "llvm/DebugInfo/CodeView/StringTable.h"
 #include "llvm/Support/BinaryStreamArray.h"
 #include "llvm/Support/BinaryStreamRef.h"
 #include "llvm/Support/Endian.h"
@@ -24,22 +23,19 @@
 namespace llvm {
 class BinaryStreamReader;
 
-namespace msf {
-class MappedBlockStream;
-}
-
 namespace pdb {
 
-struct PDBStringTableHeader;
-
 class PDBStringTable {
 public:
-  Error reload(BinaryStreamReader &Reader);
+  PDBStringTable();
+
+  Error load(BinaryStreamReader &Stream);
 
   uint32_t getByteSize() const;
-  uint32_t getNameCount() const;
-  uint32_t getHashVersion() const;
-  uint32_t getSignature() const;
+
+  uint32_t getNameCount() const { return NameCount; }
+  uint32_t getHashVersion() const { return HashVersion; }
+  uint32_t getSignature() const { return Signature; }
 
   StringRef getStringForID(uint32_t ID) const;
   uint32_t getIDForString(StringRef Str) const;
@@ -47,15 +43,11 @@ public:
   FixedStreamArray<support::ulittle32_t> name_ids() const;
 
 private:
-  Error readHeader(BinaryStreamReader &Reader);
-  Error readStrings(BinaryStreamReader &Reader);
-  Error readHashTable(BinaryStreamReader &Reader);
-  Error readEpilogue(BinaryStreamReader &Reader);
-
-  const PDBStringTableHeader *Header = nullptr;
-  codeview::StringTableRef Strings;
+  BinaryStreamRef NamesBuffer;
   FixedStreamArray<support::ulittle32_t> IDs;
   uint32_t ByteSize = 0;
+  uint32_t Signature = 0;
+  uint32_t HashVersion = 0;
   uint32_t NameCount = 0;
 };
 

include/llvm/DebugInfo/PDB/Native/PDBStringTableBuilder.h

@@ -16,39 +16,27 @@
 
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/StringRef.h"
-#include "llvm/DebugInfo/CodeView/StringTable.h"
 #include "llvm/Support/Error.h"
 #include <vector>
 
 namespace llvm {
 class BinaryStreamWriter;
-class WritableBinaryStreamRef;
-
-namespace msf {
-struct MSFLayout;
-}
 
 namespace pdb {
 
-class PDBFileBuilder;
-
 class PDBStringTableBuilder {
 public:
   // If string S does not exist in the string table, insert it.
   // Returns the ID for S.
   uint32_t insert(StringRef S);
+  uint32_t getStringIndex(StringRef S);
 
-  uint32_t calculateSerializedSize() const;
+  uint32_t finalize();
   Error commit(BinaryStreamWriter &Writer) const;
 
 private:
-  uint32_t calculateHashTableSize() const;
-  Error writeHeader(BinaryStreamWriter &Writer) const;
-  Error writeStrings(BinaryStreamWriter &Writer) const;
-  Error writeHashTable(BinaryStreamWriter &Writer) const;
-  Error writeEpilogue(BinaryStreamWriter &Writer) const;
-
-  codeview::StringTable Strings;
+  DenseMap<StringRef, uint32_t> Strings;
+  uint32_t StringSize = 1;
 };
 
 } // end namespace pdb

include/llvm/DebugInfo/PDB/Native/RawTypes.h

@@ -308,9 +308,9 @@ struct InfoStreamHeader {
 
 /// The header preceeding the /names stream.
 struct PDBStringTableHeader {
-  support::ulittle32_t Signature;   // PDBStringTableSignature
-  support::ulittle32_t HashVersion; // 1 or 2
-  support::ulittle32_t ByteSize;    // Number of bytes of names buffer.
+  support::ulittle32_t Signature;
+  support::ulittle32_t HashVersion;
+  support::ulittle32_t ByteSize;
 };
 
 const uint32_t PDBStringTableSignature = 0xEFFEEFFE;

include/llvm/Support/BinaryStreamReader.h

@@ -31,7 +31,6 @@ namespace llvm {
 /// are overridable.
 class BinaryStreamReader {
 public:
-  BinaryStreamReader() = default;
   explicit BinaryStreamReader(BinaryStreamRef Stream);
   virtual ~BinaryStreamReader() {}
 
@@ -244,9 +243,6 @@ public:
   /// \returns the next byte in the stream.
   uint8_t peek() const;
 
-  std::pair<BinaryStreamReader, BinaryStreamReader>
-  split(uint32_t Offset) const;
-
 private:
   BinaryStreamRef Stream;
   uint32_t Offset;

include/llvm/Support/BinaryStreamWriter.h

@@ -20,7 +20,6 @@
 #include "llvm/Support/Error.h"
 #include <cstdint>
 #include <type_traits>
-#include <utility>
 
 namespace llvm {
 
@@ -31,6 +30,8 @@ namespace llvm {
 /// although no methods are overridable.
 class BinaryStreamWriter {
 public:
+  // FIXME: We should be able to slice and drop_front etc on Writers / Readers.
+
   BinaryStreamWriter() = default;
   explicit BinaryStreamWriter(WritableBinaryStreamRef Stream);
   virtual ~BinaryStreamWriter() {}
@@ -151,9 +152,6 @@ public:
     return writeStreamRef(Array.getUnderlyingStream());
   }
 
-  /// Splits the Writer into two Writers at a given offset.
-  std::pair<BinaryStreamWriter, BinaryStreamWriter> split(uint32_t Off) const;
-
   void setOffset(uint32_t Off) { Offset = Off; }
   uint32_t getOffset() const { return Offset; }
   uint32_t getLength() const { return Stream.getLength(); }

lib/DebugInfo/CodeView/CMakeLists.txt

@@ -15,7 +15,6 @@ add_llvm_library(LLVMDebugInfoCodeView
   ModuleDebugLineFragment.cpp
   ModuleDebugUnknownFragment.cpp
   RecordSerialization.cpp
-  StringTable.cpp
   SymbolRecordMapping.cpp
   SymbolDumper.cpp
   SymbolSerializer.cpp

lib/DebugInfo/CodeView/StringTable.cpp

@@ -1,65 +0,0 @@
-//===- StringTable.cpp - CodeView String Table Reader/Writer ----*- 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/CodeView/StringTable.h"
-
-#include "llvm/Support/BinaryStream.h"
-#include "llvm/Support/BinaryStreamReader.h"
-#include "llvm/Support/BinaryStreamWriter.h"
-
-using namespace llvm;
-using namespace llvm::codeview;
-
-StringTableRef::StringTableRef() {}
-
-Error StringTableRef::initialize(BinaryStreamReader &Reader) {
-  return Reader.readStreamRef(Stream, Reader.bytesRemaining());
-}
-
-StringRef StringTableRef::getString(uint32_t Offset) const {
-  BinaryStreamReader Reader(Stream);
-  Reader.setOffset(Offset);
-  StringRef Result;
-  Error EC = Reader.readCString(Result);
-  assert(!EC);
-  consumeError(std::move(EC));
-  return Result;
-}
-
-uint32_t StringTable::insert(StringRef S) {
-  auto P = Strings.insert({S, StringSize});
-
-  // If a given string didn't exist in the string table, we want to increment
-  // the string table size.
-  if (P.second)
-    StringSize += S.size() + 1; // +1 for '\0'
-  return P.first->second;
-}
-
-uint32_t StringTable::calculateSerializedSize() const { return StringSize; }
-
-Error StringTable::commit(BinaryStreamWriter &Writer) const {
-  assert(Writer.bytesRemaining() == StringSize);
-  uint32_t MaxOffset = 1;
-
-  for (auto &Pair : Strings) {
-    StringRef S = Pair.getKey();
-    uint32_t Offset = Pair.getValue();
-    Writer.setOffset(Offset);
-    if (auto EC = Writer.writeCString(S))
-      return EC;
-    MaxOffset = std::max<uint32_t>(MaxOffset, Offset + S.size() + 1);
-  }
-
-  Writer.setOffset(MaxOffset);
-  assert(Writer.bytesRemaining() == 0);
-  return Error::success();
-}
-
-uint32_t StringTable::size() const { return Strings.size(); }

lib/DebugInfo/PDB/Native/DbiStream.cpp

@@ -146,7 +146,7 @@ Error DbiStream::reload() {
 
   if (ECSubstream.getLength() > 0) {
     BinaryStreamReader ECReader(ECSubstream);
-    if (auto EC = ECNames.reload(ECReader))
+    if (auto EC = ECNames.load(ECReader))
       return EC;
   }
 

lib/DebugInfo/PDB/Native/PDBFile.cpp

@@ -338,7 +338,7 @@ Expected<SymbolStream &> PDBFile::getPDBSymbolStream() {
 }
 
 Expected<PDBStringTable &> PDBFile::getStringTable() {
-  if (!Strings) {
+  if (!Strings || !PDBStringTableStream) {
     auto IS = getPDBInfoStream();
     if (!IS)
       return IS.takeError();
@@ -350,13 +350,12 @@ Expected<PDBStringTable &> PDBFile::getStringTable() {
     if (!NS)
       return NS.takeError();
 
-    auto N = llvm::make_unique<PDBStringTable>();
     BinaryStreamReader Reader(**NS);
-    if (auto EC = N->reload(Reader))
+    auto N = llvm::make_unique<PDBStringTable>();
+    if (auto EC = N->load(Reader))
       return std::move(EC);
-    assert(Reader.bytesRemaining() == 0);
-    StringTableStream = std::move(*NS);
     Strings = std::move(N);
+    PDBStringTableStream = std::move(*NS);
   }
   return *Strings;
 }

lib/DebugInfo/PDB/Native/PDBFileBuilder.cpp

@@ -80,9 +80,9 @@ Error PDBFileBuilder::addNamedStream(StringRef Name, uint32_t Size) {
 }
 
 Expected<msf::MSFLayout> PDBFileBuilder::finalizeMsfLayout() {
-  uint32_t StringsLen = Strings.calculateSerializedSize();
+  uint32_t PDBStringTableSize = Strings.finalize();
 
-  if (auto EC = addNamedStream("/names", StringsLen))
+  if (auto EC = addNamedStream("/names", PDBStringTableSize))
     return std::move(EC);
   if (auto EC = addNamedStream("/LinkInfo", 0))
     return std::move(EC);
@@ -109,13 +109,6 @@ Expected<msf::MSFLayout> PDBFileBuilder::finalizeMsfLayout() {
   return Msf->build();
 }
 
-Expected<uint32_t> PDBFileBuilder::getNamedStreamIndex(StringRef Name) const {
-  uint32_t SN = 0;
-  if (!NamedStreams.get(Name, SN))
-    return llvm::make_error<pdb::RawError>(raw_error_code::no_stream);
-  return SN;
-}
-
 Error PDBFileBuilder::commit(StringRef Filename) {
   auto ExpectedLayout = finalizeMsfLayout();
   if (!ExpectedLayout)
@@ -153,12 +146,12 @@ Error PDBFileBuilder::commit(StringRef Filename) {
       return EC;
   }
 
-  auto ExpectedSN = getNamedStreamIndex("/names");
-  if (!ExpectedSN)
-    return ExpectedSN.takeError();
+  uint32_t PDBStringTableStreamNo = 0;
+  if (!NamedStreams.get("/names", PDBStringTableStreamNo))
+    return llvm::make_error<pdb::RawError>(raw_error_code::no_stream);
 
-  auto NS = WritableMappedBlockStream::createIndexedStream(Layout, Buffer,
-                                                           *ExpectedSN);
+  auto NS = WritableMappedBlockStream::createIndexedStream(
+      Layout, Buffer, PDBStringTableStreamNo);
   BinaryStreamWriter NSWriter(*NS);
   if (auto EC = Strings.commit(NSWriter))
     return EC;

lib/DebugInfo/PDB/Native/PDBStringTable.cpp

@@ -1,4 +1,5 @@
-//===- PDBStringTable.cpp - PDB String Table ---------------------*- C++-*-===//
+//===- PDBStringTable.cpp - PDB String Table -----------------------*- C++
+//-*-===//
 //
 //                     The LLVM Compiler Infrastructure
 //
@@ -10,7 +11,6 @@
 #include "llvm/DebugInfo/PDB/Native/PDBStringTable.h"
 
 #include "llvm/ADT/ArrayRef.h"
-#include "llvm/DebugInfo/MSF/MappedBlockStream.h"
 #include "llvm/DebugInfo/PDB/Native/Hash.h"
 #include "llvm/DebugInfo/PDB/Native/RawError.h"
 #include "llvm/DebugInfo/PDB/Native/RawTypes.h"
@@ -21,91 +21,71 @@ using namespace llvm;
 using namespace llvm::support;
 using namespace llvm::pdb;
 
-uint32_t PDBStringTable::getByteSize() const { return ByteSize; }
-uint32_t PDBStringTable::getNameCount() const { return NameCount; }
-uint32_t PDBStringTable::getHashVersion() const { return Header->HashVersion; }
-uint32_t PDBStringTable::getSignature() const { return Header->Signature; }
+PDBStringTable::PDBStringTable() {}
 
-Error PDBStringTable::readHeader(BinaryStreamReader &Reader) {
-  if (auto EC = Reader.readObject(Header))
+Error PDBStringTable::load(BinaryStreamReader &Stream) {
+  ByteSize = Stream.getLength();
+
+  const PDBStringTableHeader *H;
+  if (auto EC = Stream.readObject(H))
     return EC;
 
-  if (Header->Signature != PDBStringTableSignature)
+  if (H->Signature != PDBStringTableSignature)
     return make_error<RawError>(raw_error_code::corrupt_file,
                                 "Invalid hash table signature");
-  if (Header->HashVersion != 1 && Header->HashVersion != 2)
+  if (H->HashVersion != 1 && H->HashVersion != 2)
     return make_error<RawError>(raw_error_code::corrupt_file,
                                 "Unsupported hash version");
 
-  assert(Reader.bytesRemaining() == 0);
-  return Error::success();
-}
-
-Error PDBStringTable::readStrings(BinaryStreamReader &Reader) {
-  if (auto EC = Strings.initialize(Reader)) {
+  Signature = H->Signature;
+  HashVersion = H->HashVersion;
+  if (auto EC = Stream.readStreamRef(NamesBuffer, H->ByteSize))
     return joinErrors(std::move(EC),
                       make_error<RawError>(raw_error_code::corrupt_file,
                                            "Invalid hash table byte length"));
-  }
 
-  assert(Reader.bytesRemaining() == 0);
-  return Error::success();
-}
-
-Error PDBStringTable::readHashTable(BinaryStreamReader &Reader) {
   const support::ulittle32_t *HashCount;
-  if (auto EC = Reader.readObject(HashCount))
+  if (auto EC = Stream.readObject(HashCount))
     return EC;
 
-  if (auto EC = Reader.readArray(IDs, *HashCount)) {
+  if (auto EC = Stream.readArray(IDs, *HashCount))
     return joinErrors(std::move(EC),
                       make_error<RawError>(raw_error_code::corrupt_file,
                                            "Could not read bucket array"));
-  }
+
+  if (Stream.bytesRemaining() < sizeof(support::ulittle32_t))
+    return make_error<RawError>(raw_error_code::corrupt_file,
+                                "Missing name count");
+
+  if (auto EC = Stream.readInteger(NameCount))
+    return EC;
+
+  if (Stream.bytesRemaining() > 0)
+    return make_error<RawError>(raw_error_code::stream_too_long,
+                                "Unexpected bytes found in string table");
 
   return Error::success();
 }
 
-Error PDBStringTable::readEpilogue(BinaryStreamReader &Reader) {
-  if (auto EC = Reader.readInteger(NameCount))
-    return EC;
-
-  assert(Reader.bytesRemaining() == 0);
-  return Error::success();
-}
-
-Error PDBStringTable::reload(BinaryStreamReader &Reader) {
-
-  BinaryStreamReader SectionReader;
-
-  std::tie(SectionReader, Reader) = Reader.split(sizeof(PDBStringTableHeader));
-  if (auto EC = readHeader(SectionReader))
-    return EC;
-
-  std::tie(SectionReader, Reader) = Reader.split(Header->ByteSize);
-  if (auto EC = readStrings(SectionReader))
-    return EC;
-
-  // We don't know how long the hash table is until we parse it, so let the
-  // function responsible for doing that figure it out.
-  if (auto EC = readHashTable(Reader))
-    return EC;
-
-  std::tie(SectionReader, Reader) = Reader.split(sizeof(uint32_t));
-  if (auto EC = readEpilogue(SectionReader))
-    return EC;
-
-  assert(Reader.bytesRemaining() == 0);
-  return Error::success();
-}
+uint32_t PDBStringTable::getByteSize() const { return ByteSize; }
 
 StringRef PDBStringTable::getStringForID(uint32_t ID) const {
-  return Strings.getString(ID);
+  if (ID == IDs[0])
+    return StringRef();
+
+  // NamesBuffer is a buffer of null terminated strings back to back.  ID is
+  // the starting offset of the string we're looking for.  So just seek into
+  // the desired offset and a read a null terminated stream from that offset.
+  StringRef Result;
+  BinaryStreamReader NameReader(NamesBuffer);
+  NameReader.setOffset(ID);
+  if (auto EC = NameReader.readCString(Result))
+    consumeError(std::move(EC));
+  return Result;
 }
 
 uint32_t PDBStringTable::getIDForString(StringRef Str) const {
-  uint32_t Hash =
-      (Header->HashVersion == 1) ? hashStringV1(Str) : hashStringV2(Str);
+  uint32_t Hash = (HashVersion == 1) ? hashStringV1(Str) : hashStringV2(Str);
   size_t Count = IDs.size();
   uint32_t Start = Hash % Count;
   for (size_t I = 0; I < Count; ++I) {

lib/DebugInfo/PDB/Native/PDBStringTableBuilder.cpp

@@ -8,23 +8,31 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/DebugInfo/PDB/Native/PDBStringTableBuilder.h"
-
 #include "llvm/ADT/ArrayRef.h"
-#include "llvm/DebugInfo/MSF/MappedBlockStream.h"
 #include "llvm/DebugInfo/PDB/Native/Hash.h"
-#include "llvm/DebugInfo/PDB/Native/PDBFileBuilder.h"
 #include "llvm/DebugInfo/PDB/Native/RawTypes.h"
 #include "llvm/Support/BinaryStreamWriter.h"
 #include "llvm/Support/Endian.h"
 
 using namespace llvm;
-using namespace llvm::msf;
 using namespace llvm::support;
 using namespace llvm::support::endian;
 using namespace llvm::pdb;
 
 uint32_t PDBStringTableBuilder::insert(StringRef S) {
-  return Strings.insert(S);
+  auto P = Strings.insert({S, StringSize});
+
+  // If a given string didn't exist in the string table, we want to increment
+  // the string table size.
+  if (P.second)
+    StringSize += S.size() + 1; // +1 for '\0'
+  return P.first->second;
+}
+
+uint32_t PDBStringTableBuilder::getStringIndex(StringRef S) {
+  auto Iter = Strings.find(S);
+  assert(Iter != Strings.end());
+  return Iter->second;
 }
 
 static uint32_t computeBucketCount(uint32_t NumStrings) {
@@ -36,52 +44,49 @@ static uint32_t computeBucketCount(uint32_t NumStrings) {
   return (NumStrings + 1) * 1.25;
 }
 
-uint32_t PDBStringTableBuilder::calculateHashTableSize() const {
-  uint32_t Size = sizeof(uint32_t); // Hash table begins with 4-byte size field.
-  Size += sizeof(uint32_t) * computeBucketCount(Strings.size());
-
-  return Size;
-}
-
-uint32_t PDBStringTableBuilder::calculateSerializedSize() const {
+uint32_t PDBStringTableBuilder::finalize() {
   uint32_t Size = 0;
   Size += sizeof(PDBStringTableHeader);
-  Size += Strings.calculateSerializedSize();
-  Size += calculateHashTableSize();
-  Size += sizeof(uint32_t); // The /names stream ends with the string count.
+  Size += StringSize;
+  Size += sizeof(uint32_t); // Hash table begins with 4-byte size field.
+
+  uint32_t BucketCount = computeBucketCount(Strings.size());
+  Size += BucketCount * sizeof(uint32_t);
+
+  Size +=
+      sizeof(uint32_t); // The /names stream ends with the number of strings.
   return Size;
 }
 
-Error PDBStringTableBuilder::writeHeader(BinaryStreamWriter &Writer) const {
+Error PDBStringTableBuilder::commit(BinaryStreamWriter &Writer) const {
   // Write a header
   PDBStringTableHeader H;
   H.Signature = PDBStringTableSignature;
   H.HashVersion = 1;
-  H.ByteSize = Strings.calculateSerializedSize();
+  H.ByteSize = StringSize;
   if (auto EC = Writer.writeObject(H))
     return EC;
-  assert(Writer.bytesRemaining() == 0);
-  return Error::success();
-}
 
-Error PDBStringTableBuilder::writeStrings(BinaryStreamWriter &Writer) const {
-  if (auto EC = Strings.commit(Writer))
-    return EC;
+  // Write a string table.
+  uint32_t StringStart = Writer.getOffset();
+  for (auto Pair : Strings) {
+    StringRef S = Pair.first;
+    uint32_t Offset = Pair.second;
+    Writer.setOffset(StringStart + Offset);
+    if (auto EC = Writer.writeCString(S))
+      return EC;
+  }
+  Writer.setOffset(StringStart + StringSize);
 
-  assert(Writer.bytesRemaining() == 0);
-  return Error::success();
-}
-
-Error PDBStringTableBuilder::writeHashTable(BinaryStreamWriter &Writer) const {
   // Write a hash table.
   uint32_t BucketCount = computeBucketCount(Strings.size());
   if (auto EC = Writer.writeInteger(BucketCount))
     return EC;
   std::vector<ulittle32_t> Buckets(BucketCount);
 
-  for (auto &Pair : Strings) {
-    StringRef S = Pair.getKey();
-    uint32_t Offset = Pair.getValue();
+  for (auto Pair : Strings) {
+    StringRef S = Pair.first;
+    uint32_t Offset = Pair.second;
     uint32_t Hash = hashStringV1(S);
 
     for (uint32_t I = 0; I != BucketCount; ++I) {
@@ -97,37 +102,7 @@ Error PDBStringTableBuilder::writeHashTable(BinaryStreamWriter &Writer) const {
 
   if (auto EC = Writer.writeArray(ArrayRef<ulittle32_t>(Buckets)))
     return EC;
-
-  assert(Writer.bytesRemaining() == 0);
-  return Error::success();
-}
-
-Error PDBStringTableBuilder::writeEpilogue(BinaryStreamWriter &Writer) const {
-  if (auto EC = Writer.writeInteger<uint32_t>(Strings.size()))
-    return EC;
-  assert(Writer.bytesRemaining() == 0);
-  return Error::success();
-}
-
-Error PDBStringTableBuilder::commit(BinaryStreamWriter &Writer) const {
-  BinaryStreamWriter SectionWriter;
-
-  std::tie(SectionWriter, Writer) = Writer.split(sizeof(PDBStringTableHeader));
-  if (auto EC = writeHeader(SectionWriter))
-    return EC;
-
-  std::tie(SectionWriter, Writer) =
-      Writer.split(Strings.calculateSerializedSize());
-  if (auto EC = writeStrings(SectionWriter))
-    return EC;
-
-  std::tie(SectionWriter, Writer) = Writer.split(calculateHashTableSize());
-  if (auto EC = writeHashTable(SectionWriter))
-    return EC;
-
-  std::tie(SectionWriter, Writer) = Writer.split(sizeof(uint32_t));
-  if (auto EC = writeEpilogue(SectionWriter))
-    return EC;
-
+  if (auto EC = Writer.writeInteger(static_cast<uint32_t>(Strings.size())))
+    return EC;
   return Error::success();
 }

lib/DebugInfo/PDB/Native/StringTableStreamBuilder.cpp

@@ -1,123 +0,0 @@
-//===- StringTableStreamBuilder.cpp - PDB String Table ----------*- 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/Native/StringTableStreamBuilder.h"
-#include "llvm/ADT/ArrayRef.h"
-#include "llvm/DebugInfo/PDB/Native/Hash.h"
-#include "llvm/DebugInfo/PDB/Native/RawTypes.h"
-#include "llvm/Support/BinaryStreamWriter.h"
-#include "llvm/Support/Endian.h"
-
-using namespace llvm;
-using namespace llvm::support;
-using namespace llvm::support::endian;
-using namespace llvm::pdb;
-
-uint32_t StringTableStreamBuilder::insert(StringRef S) {
-  return Strings.insert(S);
-}
-
-static uint32_t computeBucketCount(uint32_t NumStrings) {
-  // The /names stream is basically an on-disk open-addressing hash table.
-  // Hash collisions are resolved by linear probing. We cannot make
-  // utilization 100% because it will make the linear probing extremely
-  // slow. But lower utilization wastes disk space. As a reasonable
-  // load factor, we choose 80%. We need +1 because slot 0 is reserved.
-  return (NumStrings + 1) * 1.25;
-}
-
-uint32_t StringTableStreamBuilder::hashTableSize() const {
-  uint32_t Size = sizeof(uint32_t); // Hash table begins with 4-byte size field.
-
-  Size += computeBucketCount(Strings.size()) * sizeof(uint32_t);
-  return Size;
-}
-
-uint32_t StringTableStreamBuilder::calculateSerializedSize() const {
-  uint32_t Size = 0;
-  Size += sizeof(StringTableHeader);
-  Size += Strings.calculateSerializedSize();
-  Size += hashTableSize();
-  Size += sizeof(uint32_t); // The table ends with the number of strings.
-  return Size;
-}
-
-Error StringTableStreamBuilder::writeHeader(BinaryStreamWriter &Writer) const {
-  // Write a header
-  StringTableHeader H;
-  H.Signature = StringTableSignature;
-  H.HashVersion = 1;
-  H.ByteSize = Strings.calculateSerializedSize();
-  if (auto EC = Writer.writeObject(H))
-    return EC;
-
-  assert(Writer.bytesRemaining() == 0);
-  return Error::success();
-}
-
-Error StringTableStreamBuilder::writeStrings(BinaryStreamWriter &Writer) const {
-  if (auto EC = Strings.commit(Writer))
-    return EC;
-
-  assert(Writer.bytesRemaining() == 0);
-  return Error::success();
-}
-
-Error StringTableStreamBuilder::writeHashTable(
-    BinaryStreamWriter &Writer) const {
-  // Write a hash table.
-  uint32_t BucketCount = computeBucketCount(Strings.size());
-  if (auto EC = Writer.writeInteger(BucketCount))
-    return EC;
-
-  std::vector<ulittle32_t> Buckets(BucketCount);
-
-  for (auto &Pair : Strings) {
-    StringRef S = Pair.getKey();
-    uint32_t Offset = Pair.getValue();
-    uint32_t Hash = hashStringV1(S);
-
-    for (uint32_t I = 0; I != BucketCount; ++I) {
-      uint32_t Slot = (Hash + I) % BucketCount;
-      if (Slot == 0)
-        continue; // Skip reserved slot
-      if (Buckets[Slot] != 0)
-        continue;
-      Buckets[Slot] = Offset;
-      break;
-    }
-  }
-
-  if (auto EC = Writer.writeArray(makeArrayRef(Buckets)))
-    return EC;
-  assert(Writer.bytesRemaining() == 0);
-  return Error::success();
-}
-
-Error StringTableStreamBuilder::commit(BinaryStreamWriter &Writer) const {
-  BinaryStreamWriter Section;
-
-  std::tie(Section, Writer) = Writer.split(sizeof(StringTableHeader));
-  if (auto EC = writeHeader(Section))
-    return EC;
-
-  std::tie(Section, Writer) = Writer.split(Strings.calculateSerializedSize());
-  if (auto EC = writeStrings(Section))
-    return EC;
-
-  std::tie(Section, Writer) = Writer.split(hashTableSize());
-  if (auto EC = writeHashTable(Section))
-    return EC;
-
-  if (auto EC = Writer.writeInteger<uint32_t>(Strings.size()))
-    return EC;
-
-  assert(Writer.bytesRemaining() == 0);
-  return Error::success();
-}

lib/Support/BinaryStreamReader.cpp

@@ -93,16 +93,3 @@ uint8_t BinaryStreamReader::peek() const {
   llvm::consumeError(std::move(EC));
   return Buffer[0];
 }
-
-std::pair<BinaryStreamReader, BinaryStreamReader>
-BinaryStreamReader::split(uint32_t Off) const {
-  assert(getLength() >= Off);
-
-  BinaryStreamRef First = Stream.drop_front(Offset);
-
-  BinaryStreamRef Second = First.drop_front(Off);
-  First = First.keep_front(Off);
-  BinaryStreamReader W1{First};
-  BinaryStreamReader W2{Second};
-  return std::make_pair(W1, W2);
-}

lib/Support/BinaryStreamWriter.cpp

@@ -59,19 +59,6 @@ Error BinaryStreamWriter::writeStreamRef(BinaryStreamRef Ref, uint32_t Length) {
   return Error::success();
 }
 
-std::pair<BinaryStreamWriter, BinaryStreamWriter>
-BinaryStreamWriter::split(uint32_t Off) const {
-  assert(getLength() >= Off);
-
-  WritableBinaryStreamRef First = Stream.drop_front(Offset);
-
-  WritableBinaryStreamRef Second = First.drop_front(Off);
-  First = First.keep_front(Off);
-  BinaryStreamWriter W1{First};
-  BinaryStreamWriter W2{Second};
-  return std::make_pair(W1, W2);
-}
-
 Error BinaryStreamWriter::padToAlignment(uint32_t Align) {
   uint32_t NewOffset = alignTo(Offset, Align);
   if (NewOffset > getLength())

unittests/DebugInfo/PDB/StringTableBuilderTest.cpp

@@ -33,7 +33,7 @@ TEST_F(StringTableBuilderTest, Simple) {
   EXPECT_EQ(1U, Builder.insert("foo"));
   EXPECT_EQ(9U, Builder.insert("baz"));
 
-  std::vector<uint8_t> Buffer(Builder.calculateSerializedSize());
+  std::vector<uint8_t> Buffer(Builder.finalize());
   MutableBinaryByteStream OutStream(Buffer, little);
   BinaryStreamWriter Writer(OutStream);
   EXPECT_NO_ERROR(Builder.commit(Writer));
@@ -42,7 +42,7 @@ TEST_F(StringTableBuilderTest, Simple) {
   BinaryByteStream InStream(Buffer, little);
   BinaryStreamReader Reader(InStream);
   PDBStringTable Table;
-  EXPECT_NO_ERROR(Table.reload(Reader));
+  EXPECT_NO_ERROR(Table.load(Reader));
 
   EXPECT_EQ(3U, Table.getNameCount());
   EXPECT_EQ(1U, Table.getHashVersion());