Slightly simplify MappedBlockStream::createIndexedStream() calls

[thakis]

Summary

All callers had a PDBFile object at hand, so call Pdb.createIndexedStream() instead, which pre-populates all the arguments (and returns nullptr for kInvalidStreamIndex).

Also change safelyCreateIndexedStream() to only take the string index, and update callers. Make the method public and call it in two places that manually did the bounds checking before.

No intended behavior change.

[rnk]

lgtm

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

ArrayRef<ArrayRef<support::ulittle32_t>> getStreamMap() const {
     return ContainerLayout.StreamMap;
   }
 
   const msf::MSFLayout &getMsfLayout() const { return ContainerLayout; }
   BinaryStreamRef getMsfBuffer() const { return *Buffer; }
 
   ArrayRef<support::ulittle32_t> getDirectoryBlockArray() const;
 
-  std::unique_ptr<msf::MappedBlockStream> createIndexedStream(uint16_t SN);
+  std::unique_ptr<msf::MappedBlockStream>
+  createIndexedStream(uint16_t SN) const;
+  Expected<std::unique_ptr<msf::MappedBlockStream>>
+  safelyCreateIndexedStream(uint32_t StreamIndex) const;
 
   msf::MSFStreamLayout getStreamLayout(uint32_t StreamIdx) const;
   msf::MSFStreamLayout getFpmStreamLayout() const;
 
   Error parseFileHeaders();
   Error parseStreamData();
 
   Expected<InfoStream &> getPDBInfoStream();
public:
   bool hasPDBPublicsStream();
   bool hasPDBSymbolStream();
   bool hasPDBTpiStream() const;
   bool hasPDBStringTable();
 
   uint32_t getPointerSize();
 
 private:
-  Expected<std::unique_ptr<msf::MappedBlockStream>>
-  safelyCreateIndexedStream(const msf::MSFLayout &Layout,
-                            BinaryStreamRef MsfData,
-                            uint32_t StreamIndex) const;
-
   std::string FilePath;
   BumpPtrAllocator &Allocator;
 
   std::unique_ptr<BinaryStream> Buffer;
 
   msf::MSFLayout ContainerLayout;
 
   std::unique_ptr<GlobalsStream> Globals;

llvm/lib/DebugInfo/PDB/Native/DbiStream.cpp

DbiStream::createIndexedStreamForHeaderType(PDBFile *Pdb,
   if (!Pdb)
     return nullptr;
 
   if (DbgStreams.empty())
     return nullptr;
 
   uint32_t StreamNum = getDebugStreamIndex(Type);
 
-  // This means there is no such stream
+  // This means there is no such stream.
   if (StreamNum == kInvalidStreamIndex)
     return nullptr;
 
-  if (StreamNum >= Pdb->getNumStreams())
-    return make_error<RawError>(raw_error_code::no_stream);
-
-  return MappedBlockStream::createIndexedStream(
-      Pdb->getMsfLayout(), Pdb->getMsfBuffer(), StreamNum, Pdb->getAllocator());
+  return Pdb->safelyCreateIndexedStream(StreamNum);
 }
 
 BinarySubstreamRef DbiStream::getSectionContributionData() const {
   return SecContrSubstream;
 }
 
 BinarySubstreamRef DbiStream::getSecMapSubstreamData() const {
   return SecMapSubstream;

llvm/lib/DebugInfo/PDB/Native/PDBFile.cpp

Error PDBFile::parseStreamData() {
   DirectoryStream = std::move(DS);
   return Error::success();
 }
 
 ArrayRef<support::ulittle32_t> PDBFile::getDirectoryBlockArray() const {
   return ContainerLayout.DirectoryBlocks;
 }
 
-std::unique_ptr<MappedBlockStream> PDBFile::createIndexedStream(uint16_t SN) {
+std::unique_ptr<MappedBlockStream>
+PDBFile::createIndexedStream(uint16_t SN) const {
   if (SN == kInvalidStreamIndex)
     return nullptr;
   return MappedBlockStream::createIndexedStream(ContainerLayout, *Buffer, SN,
                                                 Allocator);
 }
 
 MSFStreamLayout PDBFile::getStreamLayout(uint32_t StreamIdx) const {
   MSFStreamLayout Result;
   auto Blocks = getStreamBlockList(StreamIdx);
   Result.Blocks.assign(Blocks.begin(), Blocks.end());
   Result.Length = getStreamByteSize(StreamIdx);
   return Result;
 }
 
 msf::MSFStreamLayout PDBFile::getFpmStreamLayout() const {
   return msf::getFpmStreamLayout(ContainerLayout);
 }
 
 Expected<GlobalsStream &> PDBFile::getPDBGlobalsStream() {
   if (!Globals) {
     auto DbiS = getPDBDbiStream();
     if (!DbiS)
       return DbiS.takeError();
 
-    auto GlobalS = safelyCreateIndexedStream(
-        ContainerLayout, *Buffer, DbiS->getGlobalSymbolStreamIndex());
+    auto GlobalS =
+        safelyCreateIndexedStream(DbiS->getGlobalSymbolStreamIndex());
     if (!GlobalS)
       return GlobalS.takeError();
     auto TempGlobals = llvm::make_unique<GlobalsStream>(std::move(*GlobalS));
     if (auto EC = TempGlobals->reload())
       return std::move(EC);
     Globals = std::move(TempGlobals);
   }
   return *Globals;
 }
 
 Expected<InfoStream &> PDBFile::getPDBInfoStream() {
   if (!Info) {
-    auto InfoS = safelyCreateIndexedStream(ContainerLayout, *Buffer, StreamPDB);
+    auto InfoS = safelyCreateIndexedStream(StreamPDB);
     if (!InfoS)
       return InfoS.takeError();
     auto TempInfo = llvm::make_unique<InfoStream>(std::move(*InfoS));
     if (auto EC = TempInfo->reload())
       return std::move(EC);
     Info = std::move(TempInfo);
   }
   return *Info;
 }
 
 Expected<DbiStream &> PDBFile::getPDBDbiStream() {
   if (!Dbi) {
-    auto DbiS = safelyCreateIndexedStream(ContainerLayout, *Buffer, StreamDBI);
+    auto DbiS = safelyCreateIndexedStream(StreamDBI);
     if (!DbiS)
       return DbiS.takeError();
     auto TempDbi = llvm::make_unique<DbiStream>(std::move(*DbiS));
     if (auto EC = TempDbi->reload(this))
       return std::move(EC);
     Dbi = std::move(TempDbi);
   }
   return *Dbi;
 }
 
 Expected<TpiStream &> PDBFile::getPDBTpiStream() {
   if (!Tpi) {
-    auto TpiS = safelyCreateIndexedStream(ContainerLayout, *Buffer, StreamTPI);
+    auto TpiS = safelyCreateIndexedStream(StreamTPI);
     if (!TpiS)
       return TpiS.takeError();
     auto TempTpi = llvm::make_unique<TpiStream>(*this, std::move(*TpiS));
     if (auto EC = TempTpi->reload())
       return std::move(EC);
     Tpi = std::move(TempTpi);
   }
   return *Tpi;
 }
 
 Expected<TpiStream &> PDBFile::getPDBIpiStream() {
   if (!Ipi) {
     if (!hasPDBIpiStream())
       return make_error<RawError>(raw_error_code::no_stream);
 
-    auto IpiS = safelyCreateIndexedStream(ContainerLayout, *Buffer, StreamIPI);
+    auto IpiS = safelyCreateIndexedStream(StreamIPI);
     if (!IpiS)
       return IpiS.takeError();
     auto TempIpi = llvm::make_unique<TpiStream>(*this, std::move(*IpiS));
     if (auto EC = TempIpi->reload())
       return std::move(EC);
     Ipi = std::move(TempIpi);
   }
   return *Ipi;
 }
 
 Expected<PublicsStream &> PDBFile::getPDBPublicsStream() {
   if (!Publics) {
     auto DbiS = getPDBDbiStream();
     if (!DbiS)
       return DbiS.takeError();
 
-    auto PublicS = safelyCreateIndexedStream(
-        ContainerLayout, *Buffer, DbiS->getPublicSymbolStreamIndex());
+    auto PublicS =
+        safelyCreateIndexedStream(DbiS->getPublicSymbolStreamIndex());
     if (!PublicS)
       return PublicS.takeError();
     auto TempPublics = llvm::make_unique<PublicsStream>(std::move(*PublicS));
     if (auto EC = TempPublics->reload())
       return std::move(EC);
     Publics = std::move(TempPublics);
   }
   return *Publics;
 }
 
 Expected<SymbolStream &> PDBFile::getPDBSymbolStream() {
   if (!Symbols) {
     auto DbiS = getPDBDbiStream();
     if (!DbiS)
       return DbiS.takeError();
 
     uint32_t SymbolStreamNum = DbiS->getSymRecordStreamIndex();
-    auto SymbolS =
-        safelyCreateIndexedStream(ContainerLayout, *Buffer, SymbolStreamNum);
+    auto SymbolS = safelyCreateIndexedStream(SymbolStreamNum);
     if (!SymbolS)
       return SymbolS.takeError();
 
     auto TempSymbols = llvm::make_unique<SymbolStream>(std::move(*SymbolS));
     if (auto EC = TempSymbols->reload())
       return std::move(EC);
     Symbols = std::move(TempSymbols);
   }
   return *Symbols;
 }
 
 Expected<PDBStringTable &> PDBFile::getStringTable() {
   if (!Strings) {
     auto IS = getPDBInfoStream();
     if (!IS)
       return IS.takeError();
 
     Expected<uint32_t> ExpectedNSI = IS->getNamedStreamIndex("/names");
     if (!ExpectedNSI)
       return ExpectedNSI.takeError();
     uint32_t NameStreamIndex = *ExpectedNSI;
 
-    auto NS =
-        safelyCreateIndexedStream(ContainerLayout, *Buffer, NameStreamIndex);
+    auto NS = safelyCreateIndexedStream(NameStreamIndex);
     if (!NS)
       return NS.takeError();
 
     auto N = llvm::make_unique<PDBStringTable>();
     BinaryStreamReader Reader(**NS);
     if (auto EC = N->reload(Reader))
       return std::move(EC);
     assert(Reader.bytesRemaining() == 0);
bool PDBFile::hasPDBStringTable() {
   return true;
 }
 
 /// Wrapper around MappedBlockStream::createIndexedStream() that checks if a
 /// stream with that index actually exists.  If it does not, the return value
 /// will have an MSFError with code msf_error_code::no_stream.  Else, the return
 /// value will contain the stream returned by createIndexedStream().
 Expected<std::unique_ptr<MappedBlockStream>>
-PDBFile::safelyCreateIndexedStream(const MSFLayout &Layout,
-                                   BinaryStreamRef MsfData,
-                                   uint32_t StreamIndex) const {
+PDBFile::safelyCreateIndexedStream(uint32_t StreamIndex) const {
   if (StreamIndex >= getNumStreams())
+    // This rejects kInvalidStreamIndex with an error as well.
     return make_error<RawError>(raw_error_code::no_stream);
-  return MappedBlockStream::createIndexedStream(Layout, MsfData, StreamIndex,
-                                                Allocator);
+  return createIndexedStream(StreamIndex);
 }

llvm/lib/DebugInfo/PDB/Native/TpiStream.cpp

Error TpiStream::reload() {
 
   BinaryStreamReader RecordReader(TypeRecordsSubstream.StreamData);
   if (auto EC =
           RecordReader.readArray(TypeRecords, TypeRecordsSubstream.size()))
     return EC;
 
   // Hash indices, hash values, etc come from the hash stream.
   if (Header->HashStreamIndex != kInvalidStreamIndex) {
-    if (Header->HashStreamIndex >= Pdb.getNumStreams())
+    auto HS = Pdb.safelyCreateIndexedStream(Header->HashStreamIndex);
+    if (!HS) {
+      consumeError(HS.takeError());
       return make_error<RawError>(raw_error_code::corrupt_file,
                                   "Invalid TPI hash stream index.");
-
-    auto HS = MappedBlockStream::createIndexedStream(
-        Pdb.getMsfLayout(), Pdb.getMsfBuffer(), Header->HashStreamIndex,
-        Pdb.getAllocator());
-    BinaryStreamReader HSR(*HS);
+    }
+    BinaryStreamReader HSR(**HS);
 
     // There should be a hash value for every type record, or no hashes at all.
     uint32_t NumHashValues =
         Header->HashValueBuffer.Length / sizeof(ulittle32_t);
     if (NumHashValues != getNumTypeRecords() && NumHashValues != 0)
       return make_error<RawError>(
           raw_error_code::corrupt_file,
           "TPI hash count does not match with the number of type records.");
     HSR.setOffset(Header->HashValueBuffer.Off);
     if (auto EC = HSR.readArray(HashValues, NumHashValues))
       return EC;
 
     HSR.setOffset(Header->IndexOffsetBuffer.Off);
     uint32_t NumTypeIndexOffsets =
         Header->IndexOffsetBuffer.Length / sizeof(TypeIndexOffset);
     if (auto EC = HSR.readArray(TypeIndexOffsets, NumTypeIndexOffsets))
       return EC;
 
     if (Header->HashAdjBuffer.Length > 0) {
       HSR.setOffset(Header->HashAdjBuffer.Off);
       if (auto EC = HashAdjusters.load(HSR))
         return EC;
     }
 
-    HashStream = std::move(HS);
+    HashStream = std::move(*HS);
   }
 
   Types = llvm::make_unique<LazyRandomTypeCollection>(
       TypeRecords, getNumTypeRecords(), getTypeIndexOffsets());
   return Error::success();
 }
 
 PdbRaw_TpiVer TpiStream::getTpiVersion() const {

llvm/tools/llvm-pdbutil/BytesOutputStyle.cpp

P.formatLine("Mod {0:4} | `{1}`: ",
                fmt_align(I, AlignStyle::Right, std::max(Digits, 4U)),
                Modi.getModuleName());
 
   uint16_t ModiStream = Modi.getModuleStreamIndex();
   AutoIndent Indent2(P, IndentLevel);
   if (ModiStream == kInvalidStreamIndex)
     return;
 
-  auto ModStreamData = MappedBlockStream::createIndexedStream(
-      File.getMsfLayout(), File.getMsfBuffer(), ModiStream,
-      File.getAllocator());
+  auto ModStreamData = File.createIndexedStream(ModiStream);
   ModuleDebugStreamRef ModStream(Modi, std::move(ModStreamData));
   if (auto EC = ModStream.reload()) {
     P.formatLine("Could not parse debug information.");
     return;
   }
   auto Layout = File.getStreamLayout(ModiStream);
   Callback(I, ModStream, Layout);
 }

llvm/tools/llvm-pdbutil/LinePrinter.cpp

void LinePrinter::formatMsfStreamData(StringRef Label, PDBFile &File,
   }
   if (Size + Offset > File.getStreamByteSize(StreamIdx)) {
     formatLine(
         "Stream {0}: Invalid offset and size, range out of stream bounds",
         StreamIdx);
     return;
   }
 
-  auto S = MappedBlockStream::createIndexedStream(
-      File.getMsfLayout(), File.getMsfBuffer(), StreamIdx, File.getAllocator());
+  auto S = File.createIndexedStream(StreamIdx);
   if (!S) {
     NewLine();
     formatLine("Stream {0}: Not present", StreamIdx);
     return;
   }
 
   uint32_t End =
       (Size == 0) ? S->getLength() : std::min(Offset + Size, S->getLength());

llvm/tools/llvm-pdbutil/YAMLOutputStyle.cpp

for (uint32_t I = 0; I < Modules.getModuleCount(); ++I) {
         auto Files = Modules.source_files(I);
         DMI.SourceFiles.assign(Files.begin(), Files.end());
       }
 
       uint16_t ModiStream = MI.getModuleStreamIndex();
       if (ModiStream == kInvalidStreamIndex)
         continue;
 
-      auto ModStreamData = msf::MappedBlockStream::createIndexedStream(
-          File.getMsfLayout(), File.getMsfBuffer(), ModiStream,
-          File.getAllocator());
-
+      auto ModStreamData = File.createIndexedStream(ModiStream);
       pdb::ModuleDebugStreamRef ModS(MI, std::move(ModStreamData));
       if (auto EC = ModS.reload())
         return EC;
 
       auto ExpectedST = File.getStringTable();
       if (!ExpectedST)
         return ExpectedST.takeError();
       if (!opts::pdb2yaml::DumpModuleSubsections.empty() &&

llvm/tools/llvm-pdbutil/llvm-pdbutil.cpp

 
   if (!Success) {
     InfoStream &IS = cantFail(File.getPDBInfoStream());
     Index = ExitOnErr(IS.getNamedStreamIndex(opts::exportstream::Stream));
     outs() << "Dumping contents of stream '" << opts::exportstream::Stream
            << "' (index " << Index << ") to file " << OutFileName << ".\n";
   }
 
-  SourceStream = MappedBlockStream::createIndexedStream(
-      File.getMsfLayout(), File.getMsfBuffer(), Index, File.getAllocator());
+  SourceStream = File.createIndexedStream(Index);
   auto OutFile = ExitOnErr(
       FileOutputBuffer::create(OutFileName, SourceStream->getLength()));
   FileBufferByteStream DestStream(std::move(OutFile), llvm::support::little);
   BinaryStreamWriter Writer(DestStream);
   ExitOnErr(Writer.writeStreamRef(*SourceStream));
   ExitOnErr(DestStream.commit());
 }