[PDB] Add support for parsing Flags from PDB Stream.

This was discovered when running `llvm-pdbdump diff` against
two files, the second of which was generated by running the
first one through pdb2yaml and then yaml2pdb.

The second one was missing some bytes from the PDB Stream, and
tracking this down showed that at the end of the PDB Stream were
some additional bytes that we were ignoring.  Looking back
to the reference code, these seem to specify some additional
flags that indicate whether the PDB supports various optional
features.

This patch adds support for reading, writing, and round-tripping
these flags through YAML and the raw dumper, and updates the
tests accordingly.

llvm-svn: 297984

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

@@ -10,6 +10,7 @@
 #ifndef LLVM_DEBUGINFO_PDB_RAW_PDBINFOSTREAM_H
 #define LLVM_DEBUGINFO_PDB_RAW_PDBINFOSTREAM_H
 
+#include "llvm/ADT/BitmaskEnum.h"
 #include "llvm/ADT/StringMap.h"
 #include "llvm/DebugInfo/MSF/MappedBlockStream.h"
 #include "llvm/DebugInfo/PDB/Native/NamedStreamMap.h"
@@ -40,6 +41,9 @@ public:
   PDB_UniqueId getGuid() const;
   uint32_t getNamedStreamMapByteSize() const;
 
+  PdbRaw_Features getFeatures() const;
+  ArrayRef<PdbRaw_FeatureSig> getFeatureSignatures() const;
+
   const NamedStreamMap &getNamedStreams() const;
 
   uint32_t getNamedStreamIndex(llvm::StringRef Name) const;
@@ -66,6 +70,9 @@ private:
   // universally unique.
   PDB_UniqueId Guid;
 
+  std::vector<PdbRaw_FeatureSig> FeatureSignatures;
+  PdbRaw_Features Features = PdbFeatureNone;
+
   uint32_t NamedStreamMapByteSize = 0;
 
   NamedStreamMap NamedStreams;

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

@@ -38,6 +38,7 @@ public:
   void setSignature(uint32_t S);
   void setAge(uint32_t A);
   void setGuid(PDB_UniqueId G);
+  void addFeature(PdbRaw_FeatureSig Sig);
 
   uint32_t finalize();
 
@@ -49,6 +50,7 @@ public:
 private:
   msf::MSFBuilder &Msf;
 
+  std::vector<PdbRaw_FeatureSig> Features;
   PdbRaw_ImplVer Ver;
   uint32_t Sig;
   uint32_t Age;

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

@@ -10,6 +10,7 @@
 #ifndef LLVM_DEBUGINFO_PDB_RAW_PDBRAWCONSTANTS_H
 #define LLVM_DEBUGINFO_PDB_RAW_PDBRAWCONSTANTS_H
 
+#include "llvm/ADT/BitmaskEnum.h"
 #include "llvm/DebugInfo/CodeView/CodeView.h"
 
 #include <cstdint>
@@ -32,6 +33,21 @@ enum PdbRaw_ImplVer : uint32_t {
   PdbImplVC140 = 20140508,
 };
 
+enum class PdbRaw_FeatureSig : uint32_t {
+  VC110 = PdbImplVC110,
+  VC140 = PdbImplVC140,
+  NoTypeMerge = 0x4D544F4E,
+  MinimalDebugInfo = 0x494E494D,
+};
+
+enum PdbRaw_Features : uint32_t {
+  PdbFeatureNone = 0x0,
+  PdbFeatureContainsIdStream = 0x1,
+  PdbFeatureMinimalDebugInfo = 0x2,
+  PdbFeatureNoTypeMerging = 0x4,
+  LLVM_MARK_AS_BITMASK_ENUM(/* LargestValue = */ PdbFeatureNoTypeMerging)
+};
+
 enum PdbRaw_DbiVer : uint32_t {
   PdbDbiVC41 = 930803,
   PdbDbiV50 = 19960307,

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

@@ -56,6 +56,30 @@ Error InfoStream::reload() {
     return EC;
   uint32_t NewOffset = Reader.getOffset();
   NamedStreamMapByteSize = NewOffset - Offset;
+
+  bool Stop = false;
+  while (!Stop && !Reader.empty()) {
+    PdbRaw_FeatureSig Sig;
+    if (auto EC = Reader.readEnum(Sig))
+      return EC;
+    switch (Sig) {
+    case PdbRaw_FeatureSig::VC110:
+      // No other flags for VC110 PDB.
+      Stop = true;
+      LLVM_FALLTHROUGH;
+    case PdbRaw_FeatureSig::VC140:
+      Features |= PdbFeatureContainsIdStream;
+      break;
+    case PdbRaw_FeatureSig::NoTypeMerge:
+      Features |= PdbFeatureNoTypeMerging;
+      break;
+    case PdbRaw_FeatureSig::MinimalDebugInfo:
+      Features |= PdbFeatureMinimalDebugInfo;
+    default:
+      continue;
+    }
+    FeatureSignatures.push_back(Sig);
+  }
   return Error::success();
 }
 
@@ -87,6 +111,12 @@ uint32_t InfoStream::getNamedStreamMapByteSize() const {
   return NamedStreamMapByteSize;
 }
 
+PdbRaw_Features InfoStream::getFeatures() const { return Features; }
+
+ArrayRef<PdbRaw_FeatureSig> InfoStream::getFeatureSignatures() const {
+  return FeatureSignatures;
+}
+
 const NamedStreamMap &InfoStream::getNamedStreams() const {
   return NamedStreams;
 }

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

@@ -36,8 +36,13 @@ void InfoStreamBuilder::setAge(uint32_t A) { Age = A; }
 
 void InfoStreamBuilder::setGuid(PDB_UniqueId G) { Guid = G; }
 
+void InfoStreamBuilder::addFeature(PdbRaw_FeatureSig Sig) {
+  Features.push_back(Sig);
+}
+
 Error InfoStreamBuilder::finalizeMsfLayout() {
-  uint32_t Length = sizeof(InfoStreamHeader) + NamedStreams.finalize();
+  uint32_t Length = sizeof(InfoStreamHeader) + NamedStreams.finalize() +
+                    (Features.size() + 1) * sizeof(uint32_t);
   if (auto EC = Msf.setStreamSize(StreamPDB, Length))
     return EC;
   return Error::success();
@@ -57,5 +62,13 @@ Error InfoStreamBuilder::commit(const msf::MSFLayout &Layout,
   if (auto EC = Writer.writeObject(H))
     return EC;
 
-  return NamedStreams.commit(Writer);
+  if (auto EC = NamedStreams.commit(Writer))
+    return EC;
+  if (auto EC = Writer.writeInteger(0))
+    return EC;
+  for (auto E : Features) {
+    if (auto EC = Writer.writeEnum(E))
+      return EC;
+  }
+  return Error::success();
 }

llvm/test/DebugInfo/PDB/pdbdump-headers.test

@@ -71,6 +71,7 @@
 ; EMPTY-NEXT:   Signature: 0x54E507E2
 ; EMPTY-NEXT:   Age: 1
 ; EMPTY-NEXT:   Guid: {0B355641-86A0-A249-896F-9988FAE52FF0}
+; EMPTY-NEXT:   Features: 0x1
 ; EMPTY-NEXT:   Named Streams {
 ; EMPTY-NEXT:     /names: 13
 ; EMPTY-NEXT:     /LinkInfo: 5
@@ -1003,6 +1004,7 @@
 ; ALL:   Signature: 0x54E507E2
 ; ALL:   Age: 1
 ; ALL:   Guid: {0B355641-86A0-A249-896F-9988FAE52FF0}
+; ALL:   Features: 0x1
 ; ALL: }
 ; ALL: Type Info Stream (IPI) {
 ; ALL:   IPI Version: 20040203
@@ -1701,6 +1703,7 @@
 ; BIG-NEXT:   Signature: 0x571FFE67
 ; BIG-NEXT:   Age: 1
 ; BIG-NEXT:   Guid: {880ECC89-DF81-0B4F-839C-58CBD052E937}
+; BIG-NEXT:   Features: 0x1
 ; BIG-NEXT:   Named Streams {
 ; BIG-NEXT:     /names: 13
 ; BIG-NEXT:     /LinkInfo: 5

llvm/test/DebugInfo/PDB/pdbdump-readwrite.test

@@ -27,6 +27,7 @@ CHECK-NEXT:   Version: 20000404
 CHECK-NEXT:   Signature: 0x54E507E2
 CHECK-NEXT:   Age: 1
 CHECK-NEXT:   Guid: {0B355641-86A0-A249-896F-9988FAE52FF0}
+CHECK-NEXT:   Features: 0x1
 CHECK-NEXT:   Named Streams {
 CHECK:          /names: 
 CHECK:        }

llvm/test/DebugInfo/PDB/pdbdump-yaml.test

@@ -44,6 +44,7 @@
 ; YAML-NEXT:   Age:             1
 ; YAML-NEXT:   Guid:            '{0B355641-86A0-A249-896F-9988FAE52FF0}'
 ; YAML-NEXT:   Signature:       1424295906
+; YAML-NEXT:   Features:        [ VC110 ]
 ; YAML-NEXT:   Version:         VC70
 ; YAML-NEXT: ...
 

llvm/tools/llvm-pdbdump/Diff.cpp

@@ -19,11 +19,34 @@
 #include "llvm/DebugInfo/PDB/Native/StringTable.h"
 
 #include "llvm/Support/FormatAdapters.h"
+#include "llvm/Support/FormatProviders.h"
 #include "llvm/Support/FormatVariadic.h"
 
 using namespace llvm;
 using namespace llvm::pdb;
 
+namespace llvm {
+template <> struct format_provider<PdbRaw_FeatureSig> {
+  static void format(const PdbRaw_FeatureSig &Sig, raw_ostream &Stream,
+                     StringRef Style) {
+    switch (Sig) {
+    case PdbRaw_FeatureSig::MinimalDebugInfo:
+      Stream << "MinimalDebugInfo";
+      break;
+    case PdbRaw_FeatureSig::NoTypeMerge:
+      Stream << "NoTypeMerge";
+      break;
+    case PdbRaw_FeatureSig::VC110:
+      Stream << "VC110";
+      break;
+    case PdbRaw_FeatureSig::VC140:
+      Stream << "VC140";
+      break;
+    }
+  }
+};
+}
+
 template <typename R> using ValueOfRange = llvm::detail::ValueOfRange<R>;
 
 template <typename Range, typename Comp>
@@ -127,6 +150,22 @@ static bool diffAndPrint(StringRef Label, PDBFile &File1, PDBFile &File2, T V1,
   return true;
 }
 
+template <typename T>
+static bool diffAndPrint(StringRef Label, PDBFile &File1, PDBFile &File2,
+                         ArrayRef<T> V1, ArrayRef<T> V2) {
+  if (V1 == V2) {
+    outs() << formatv("  {0}: No differences detected!\n", Label);
+    return false;
+  }
+
+  outs().indent(2) << Label << "\n";
+  outs().indent(4) << formatv("{0}: {1}\n", File1.getFilePath(),
+                              make_range(V1.begin(), V1.end()));
+  outs().indent(4) << formatv("{0}: {1}\n", File2.getFilePath(),
+                              make_range(V2.begin(), V2.end()));
+  return true;
+}
+
 template <typename T>
 static bool printSymmetricDifferences(PDBFile &File1, PDBFile &File2,
                                       T &&OnlyRange1, T &&OnlyRange2,
@@ -446,6 +485,8 @@ Error DiffStyle::diffInfoStream() {
                           IS2.getSignature());
   HasDiff |=
       diffAndPrint("Version", File1, File2, IS1.getVersion(), IS2.getVersion());
+  HasDiff |= diffAndPrint("Features", File1, File2, IS1.getFeatureSignatures(),
+                          IS2.getFeatureSignatures());
   HasDiff |= diffAndPrint("Named Stream Byte Size", File1, File2,
                           IS1.getNamedStreamMapByteSize(),
                           IS2.getNamedStreamMapByteSize());

llvm/tools/llvm-pdbdump/LLVMOutputStyle.cpp

@@ -387,6 +387,7 @@ Error LLVMOutputStyle::dumpInfoStream() {
   P.printHex("Signature", IS->getSignature());
   P.printNumber("Age", IS->getAge());
   P.printObject("Guid", IS->getGuid());
+  P.printHex("Features", IS->getFeatures());
   {
     DictScope DD(P, "Named Streams");
     for (const auto &S : IS->getNamedStreams().entries())

llvm/tools/llvm-pdbdump/PdbYaml.cpp

@@ -38,6 +38,7 @@ LLVM_YAML_IS_SEQUENCE_VECTOR(llvm::pdb::yaml::PdbDbiModuleInfo)
 LLVM_YAML_IS_SEQUENCE_VECTOR(llvm::pdb::yaml::PdbSymbolRecord)
 LLVM_YAML_IS_SEQUENCE_VECTOR(llvm::pdb::yaml::PdbTpiRecord)
 LLVM_YAML_IS_SEQUENCE_VECTOR(llvm::pdb::yaml::StreamBlockList)
+LLVM_YAML_IS_FLOW_SEQUENCE_VECTOR(llvm::pdb::PdbRaw_FeatureSig)
 
 namespace llvm {
 namespace yaml {
@@ -134,6 +135,16 @@ template <> struct ScalarEnumerationTraits<llvm::pdb::PdbRaw_TpiVer> {
     io.enumCase(Value, "VC80", llvm::pdb::PdbRaw_TpiVer::PdbTpiV80);
   }
 };
+
+template <> struct ScalarEnumerationTraits<llvm::pdb::PdbRaw_FeatureSig> {
+  static void enumeration(IO &io, PdbRaw_FeatureSig &Features) {
+    io.enumCase(Features, "MinimalDebugInfo",
+                PdbRaw_FeatureSig::MinimalDebugInfo);
+    io.enumCase(Features, "NoTypeMerge", PdbRaw_FeatureSig::NoTypeMerge);
+    io.enumCase(Features, "VC110", PdbRaw_FeatureSig::VC110);
+    io.enumCase(Features, "VC140", PdbRaw_FeatureSig::VC140);
+  }
+};
 }
 }
 
@@ -187,6 +198,7 @@ void MappingTraits<PdbInfoStream>::mapping(IO &IO, PdbInfoStream &Obj) {
   IO.mapOptional("Age", Obj.Age, 1U);
   IO.mapOptional("Guid", Obj.Guid);
   IO.mapOptional("Signature", Obj.Signature, 0U);
+  IO.mapOptional("Features", Obj.Features);
   IO.mapOptional("Version", Obj.Version, PdbImplVC70);
 }
 

llvm/tools/llvm-pdbdump/PdbYaml.h

@@ -52,6 +52,7 @@ struct PdbInfoStream {
   uint32_t Signature = 0;
   uint32_t Age = 1;
   PDB_UniqueId Guid;
+  std::vector<PdbRaw_FeatureSig> Features;
   std::vector<NamedStreamMapping> NamedStreams;
 };
 

llvm/tools/llvm-pdbdump/YAMLOutputStyle.cpp

@@ -145,6 +145,7 @@ Error YAMLOutputStyle::dumpPDBStream() {
   Obj.PdbStream->Guid = InfoS.getGuid();
   Obj.PdbStream->Signature = InfoS.getSignature();
   Obj.PdbStream->Version = InfoS.getVersion();
+  Obj.PdbStream->Features = InfoS.getFeatureSignatures();
 
   return Error::success();
 }

llvm/tools/llvm-pdbdump/llvm-pdbdump.cpp

@@ -404,6 +404,8 @@ static void yamlToPdb(StringRef Path) {
   InfoBuilder.setGuid(Info.Guid);
   InfoBuilder.setSignature(Info.Signature);
   InfoBuilder.setVersion(Info.Version);
+  for (auto F : Info.Features)
+    InfoBuilder.addFeature(F);
 
   const auto &Dbi = YamlObj.DbiStream.getValueOr(DefaultDbiStream);
   auto &DbiBuilder = Builder.getDbiBuilder();
@@ -415,7 +417,7 @@ static void yamlToPdb(StringRef Path) {
   DbiBuilder.setPdbDllVersion(Dbi.PdbDllVersion);
   DbiBuilder.setVersionHeader(Dbi.VerHeader);
   for (const auto &MI : Dbi.ModInfos) {
-    auto &ModiBuilder = ExitOnErr(DbiBuilder.addModuleInfo(MI.Obj));
+    auto &ModiBuilder = ExitOnErr(DbiBuilder.addModuleInfo(MI.Mod));
 
     for (auto S : MI.SourceFiles)
       ExitOnErr(DbiBuilder.addModuleSourceFile(MI.Mod, S));