[PDB] Merge in types and items from type servers (/Zi)

[rnk]

Summary

Object files compiled with /Zi emit type information into a type server
PDB. The .debug$S section will contain a single TypeServer2Record with
the absolute path and GUID of the type server. LLD needs to load the
type server PDB and merge all types and items it finds in it into the
destination PDB.

Depends on D35495

[ruiu]

lld/COFF/PDB.cpp

125 ↗

(On Diff #106942)

Do you need an ordered map?

176 ↗

(On Diff #106942)

Reverse the condition for early break.

223–226 ↗

(On Diff #106942)

Is this correct that you are calling getPDBInfoStream only to check the existence of an Info stream?

230–238 ↗

(On Diff #106942)

Can you remove this code for now?

[rnk]

lld/COFF/PDB.cpp

125 ↗

(On Diff #106942)

I don't need ordering, but the keys and values are large (16 byte GUID + six pointers), so I want a container with a separate allocation. std::unordered_map is probably appropriate, but DenseMap is not.

223–226 ↗

(On Diff #106942)

We need it for the Guid checking code below.

230–238 ↗

(On Diff #106942)

Oh, the whole point of rebasing this on D35495 was to remove this check. We can check the GUIDs now that YAML serialization works.

[rnk]

• remove CheckGuids hack

[ruiu]

lld/COFF/PDB.cpp

175–177 ↗

(On Diff #106966)

Is this possible that Types contain an LF_TYPESERVER2 and other types? If that is impossible, maybe this is more straightforward:

if (Types.empty() || Types[0].kind() == LF_TYPESERVER2)
  return None;

...

[rnk]

• rebase, remove for loop

[rnk]

lld/COFF/PDB.cpp

175–177 ↗

(On Diff #106966)

The type array isn't a real collection, though. There's no .front(), no operator[], and begin() could equal end() if there was an error during deserialization even if empty() returns false.

I'll remove the for loop and use begin().

[ruiu]

LGTM

lld/trunk/COFF/PDB.cpp

 //===- PDB.cpp ------------------------------------------------------------===//
 //
 //                             The LLVM Linker
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 
 #include "PDB.h"
 #include "Chunks.h"
 #include "Config.h"
 #include "Error.h"
 #include "SymbolTable.h"
 #include "Symbols.h"
 #include "llvm/DebugInfo/CodeView/CVDebugRecord.h"
-#include "llvm/DebugInfo/CodeView/CVTypeVisitor.h"
 #include "llvm/DebugInfo/CodeView/DebugSubsectionRecord.h"
-#include "llvm/DebugInfo/CodeView/DebugSubsectionVisitor.h"
 #include "llvm/DebugInfo/CodeView/LazyRandomTypeCollection.h"
 #include "llvm/DebugInfo/CodeView/SymbolSerializer.h"
+#include "llvm/DebugInfo/CodeView/TypeDeserializer.h"
 #include "llvm/DebugInfo/CodeView/TypeDumpVisitor.h"
 #include "llvm/DebugInfo/CodeView/TypeIndexDiscovery.h"
 #include "llvm/DebugInfo/CodeView/TypeStreamMerger.h"
 #include "llvm/DebugInfo/CodeView/TypeTableBuilder.h"
 #include "llvm/DebugInfo/MSF/MSFBuilder.h"
 #include "llvm/DebugInfo/MSF/MSFCommon.h"
+#include "llvm/DebugInfo/PDB/GenericError.h"
 #include "llvm/DebugInfo/PDB/Native/DbiModuleDescriptorBuilder.h"
 #include "llvm/DebugInfo/PDB/Native/DbiStream.h"
 #include "llvm/DebugInfo/PDB/Native/DbiStreamBuilder.h"
 #include "llvm/DebugInfo/PDB/Native/InfoStream.h"
 #include "llvm/DebugInfo/PDB/Native/InfoStreamBuilder.h"
+#include "llvm/DebugInfo/PDB/Native/NativeSession.h"
 #include "llvm/DebugInfo/PDB/Native/PDBFile.h"
 #include "llvm/DebugInfo/PDB/Native/PDBFileBuilder.h"
 #include "llvm/DebugInfo/PDB/Native/PDBStringTableBuilder.h"
 #include "llvm/DebugInfo/PDB/Native/TpiStream.h"
 #include "llvm/DebugInfo/PDB/Native/TpiStreamBuilder.h"
+#include "llvm/DebugInfo/PDB/PDB.h"
 #include "llvm/Object/COFF.h"
 #include "llvm/Support/BinaryByteStream.h"
 #include "llvm/Support/Endian.h"
 #include "llvm/Support/FileOutputBuffer.h"
 #include "llvm/Support/Path.h"
 #include "llvm/Support/ScopedPrinter.h"
 #include <memory>
 
 using namespace lld;
 using namespace lld::coff;
 using namespace llvm;
 using namespace llvm::codeview;
 
 using llvm::object::coff_section;
 
 static ExitOnError ExitOnErr;
 
 namespace {
+/// Map from type index and item index in a type server PDB to the
+/// corresponding index in the destination PDB.
+struct CVIndexMap {
+  SmallVector<TypeIndex, 0> TPIMap;
+  SmallVector<TypeIndex, 0> IPIMap;
+  bool IsTypeServerMap = false;
+};
+
 class PDBLinker {
 public:
   PDBLinker(SymbolTable *Symtab)
       : Alloc(), Symtab(Symtab), Builder(Alloc), TypeTable(Alloc),
         IDTable(Alloc) {}
 
   /// Emit the basic PDB structure: initial streams, headers, etc.
   void initialize(const llvm::codeview::DebugInfo *DI);
 
   /// Link CodeView from each object file in the symbol table into the PDB.
   void addObjectsToPDB();
 
   /// Link CodeView from a single object file into the PDB.
   void addObjectFile(ObjectFile *File);
 
-  /// Merge the type information from the .debug$T section in the given object
-  /// file. Produce a mapping from object file type indices to type or
-  /// item indices in the final PDB.
-  void mergeDebugT(ObjectFile *File, SmallVectorImpl<TypeIndex> &TypeIndexMap);
+  /// Produce a mapping from the type and item indices used in the object
+  /// file to those in the destination PDB.
+  ///
+  /// If the object file uses a type server PDB (compiled with /Zi), merge TPI
+  /// and IPI from the type server PDB and return a map for it. Each unique type
+  /// server PDB is merged at most once, so this may return an existing index
+  /// mapping.
+  ///
+  /// If the object does not use a type server PDB (compiled with /Z7), we merge
+  /// all the type and item records from the .debug$S stream and fill in the
+  /// caller-provided ObjectIndexMap.
+  const CVIndexMap &mergeDebugT(ObjectFile *File, CVIndexMap &ObjectIndexMap);
+
+  const CVIndexMap &maybeMergeTypeServerPDB(ObjectFile *File,
+                                            TypeServer2Record &TS);
 
   /// Add the section map and section contributions to the PDB.
   void addSections(ArrayRef<uint8_t> SectionTable);
 
   /// Write the PDB to disk.
   void commit();
 
 private:
private:
 
   /// PDBs use a single global string table for filenames in the file checksum
   /// table.
   DebugStringTableSubsection PDBStrTab;
 
   llvm::SmallString<128> NativePath;
 
   std::vector<pdb::SecMapEntry> SectionMap;
+
+  /// Type index mappings of type server PDBs that we've loaded so far.
+  std::map<GUID, CVIndexMap> TypeServerIndexMappings;
 };
 }
 
 // Returns a list of all SectionChunks.
 static void addSectionContribs(SymbolTable *Symtab,
                                pdb::DbiStreamBuilder &DbiBuilder) {
   for (Chunk *C : Symtab->getChunks())
     if (auto *SC = dyn_cast<SectionChunk>(C))
static void addTypeInfo(pdb::TpiStreamBuilder &TpiBuilder,
 
   // Flatten the in memory type table.
   TypeTable.ForEachRecord([&](TypeIndex TI, ArrayRef<uint8_t> Rec) {
     // FIXME: Hash types.
     TpiBuilder.addTypeRecord(Rec, None);
   });
 }
 
-void PDBLinker::mergeDebugT(ObjectFile *File,
-                            SmallVectorImpl<TypeIndex> &TypeIndexMap) {
+static Optional<TypeServer2Record>
+maybeReadTypeServerRecord(CVTypeArray &Types) {
+  auto I = Types.begin();
+  if (I == Types.end())
+    return None;
+  const CVType &Type = *I;
+  if (Type.kind() != LF_TYPESERVER2)
+    return None;
+  TypeServer2Record TS;
+  if (auto EC = TypeDeserializer::deserializeAs(const_cast<CVType &>(Type), TS))
+    fatal(EC, "error reading type server record");
+  return std::move(TS);
+}
+
+const CVIndexMap &PDBLinker::mergeDebugT(ObjectFile *File,
+                                         CVIndexMap &ObjectIndexMap) {
   ArrayRef<uint8_t> Data = getDebugSection(File, ".debug$T");
   if (Data.empty())
-    return;
-
-  // Look for type server PDBs next to the input file. If this file has a parent
-  // archive, look next to the archive path.
-  StringRef LocalPath =
-      !File->ParentName.empty() ? File->ParentName : File->getName();
-  (void)LocalPath; // FIXME: Implement type server handling here.
+    return ObjectIndexMap;
 
   BinaryByteStream Stream(Data, support::little);
   CVTypeArray Types;
   BinaryStreamReader Reader(Stream);
   if (auto EC = Reader.readArray(Types, Reader.getLength()))
     fatal(EC, "Reader::readArray failed");
-  if (auto Err = mergeTypeAndIdRecords(IDTable, TypeTable, TypeIndexMap, Types))
-    fatal(Err, "codeview::mergeTypeStreams failed");
+
+  // Look through type servers. If we've already seen this type server, don't
+  // merge any type information.
+  if (Optional<TypeServer2Record> TS = maybeReadTypeServerRecord(Types))
+    return maybeMergeTypeServerPDB(File, *TS);
+
+  // This is a /Z7 object. Fill in the temporary, caller-provided
+  // ObjectIndexMap.
+  if (auto Err = mergeTypeAndIdRecords(IDTable, TypeTable,
+                                       ObjectIndexMap.TPIMap, Types))
+    fatal(Err, "codeview::mergeTypeAndIdRecords failed");
+  return ObjectIndexMap;
+}
+
+static Expected<std::unique_ptr<pdb::NativeSession>>
+tryToLoadPDB(const GUID &GuidFromObj, StringRef TSPath) {
+  std::unique_ptr<pdb::IPDBSession> ThisSession;
+  if (auto EC =
+          pdb::loadDataForPDB(pdb::PDB_ReaderType::Native, TSPath, ThisSession))
+    return std::move(EC);
+
+  std::unique_ptr<pdb::NativeSession> NS(
+      static_cast<pdb::NativeSession *>(ThisSession.release()));
+  pdb::PDBFile &File = NS->getPDBFile();
+  auto ExpectedInfo = File.getPDBInfoStream();
+  // All PDB Files should have an Info stream.
+  if (!ExpectedInfo)
+    return ExpectedInfo.takeError();
+
+  // Just because a file with a matching name was found and it was an actual
+  // PDB file doesn't mean it matches.  For it to match the InfoStream's GUID
+  // must match the GUID specified in the TypeServer2 record.
+  if (ExpectedInfo->getGuid() != GuidFromObj)
+    return make_error<pdb::GenericError>(
+        pdb::generic_error_code::type_server_not_found, TSPath);
+
+  return std::move(NS);
+}
+
+const CVIndexMap &PDBLinker::maybeMergeTypeServerPDB(ObjectFile *File,
+                                                     TypeServer2Record &TS) {
+  // First, check if we already loaded a PDB with this GUID. Return the type
+  // index mapping if we have it.
+  auto Insertion = TypeServerIndexMappings.insert({TS.getGuid(), CVIndexMap()});
+  CVIndexMap &IndexMap = Insertion.first->second;
+  if (!Insertion.second)
+    return IndexMap;
+
+  // Mark this map as a type server map.
+  IndexMap.IsTypeServerMap = true;
+
+  // Check for a PDB at:
+  // 1. The given file path
+  // 2. Next to the object file or archive file
+  auto ExpectedSession = tryToLoadPDB(TS.getGuid(), TS.getName());
+  if (!ExpectedSession) {
+    consumeError(ExpectedSession.takeError());
+    StringRef LocalPath =
+        !File->ParentName.empty() ? File->ParentName : File->getName();
+    SmallString<128> Path = sys::path::parent_path(LocalPath);
+    sys::path::append(Path, sys::path::filename(TS.getName()));
+    ExpectedSession = tryToLoadPDB(TS.getGuid(), Path);
+  }
+  if (auto E = ExpectedSession.takeError())
+    fatal(E, "Type server PDB was not found");
+
+  // Merge TPI first, because the IPI stream will reference type indices.
+  auto ExpectedTpi = (*ExpectedSession)->getPDBFile().getPDBTpiStream();
+  if (auto E = ExpectedTpi.takeError())
+    fatal(E, "Type server does not have TPI stream");
+  if (auto Err = mergeTypeRecords(TypeTable, IndexMap.TPIMap,
+                                  ExpectedTpi->typeArray()))
+    fatal(Err, "codeview::mergeTypeRecords failed");
+
+  // Merge IPI.
+  auto ExpectedIpi = (*ExpectedSession)->getPDBFile().getPDBIpiStream();
+  if (auto E = ExpectedIpi.takeError())
+    fatal(E, "Type server does not have TPI stream");
+  if (auto Err = mergeIdRecords(IDTable, IndexMap.TPIMap, IndexMap.IPIMap,
+                                ExpectedIpi->typeArray()))
+    fatal(Err, "codeview::mergeIdRecords failed");
+
+  return IndexMap;
 }
 
 static bool remapTypeIndex(TypeIndex &TI, ArrayRef<TypeIndex> TypeIndexMap) {
   if (TI.isSimple())
     return true;
   if (TI.toArrayIndex() >= TypeIndexMap.size())
     return false;
   TI = TypeIndexMap[TI.toArrayIndex()];
   return true;
 }
 
 static void remapTypesInSymbolRecord(ObjectFile *File,
                                      MutableArrayRef<uint8_t> Contents,
-                                     ArrayRef<TypeIndex> TypeIndexMap,
+                                     const CVIndexMap &IndexMap,
                                      ArrayRef<TiReference> TypeRefs) {
   for (const TiReference &Ref : TypeRefs) {
     unsigned ByteSize = Ref.Count * sizeof(TypeIndex);
     if (Contents.size() < Ref.Offset + ByteSize)
       fatal("symbol record too short");
+
+    // This can be an item index or a type index. Choose the appropriate map.
+    ArrayRef<TypeIndex> TypeOrItemMap = IndexMap.TPIMap;
+    if (Ref.Kind == TiRefKind::IndexRef && IndexMap.IsTypeServerMap)
+      TypeOrItemMap = IndexMap.IPIMap;
+
     MutableArrayRef<TypeIndex> TIs(
         reinterpret_cast<TypeIndex *>(Contents.data() + Ref.Offset), Ref.Count);
     for (TypeIndex &TI : TIs) {
-      if (!remapTypeIndex(TI, TypeIndexMap)) {
+      if (!remapTypeIndex(TI, TypeOrItemMap)) {
         TI = TypeIndex(SimpleTypeKind::NotTranslated);
         log("ignoring symbol record in " + File->getName() +
             " with bad type index 0x" + utohexstr(TI.getIndex()));
         continue;
       }
     }
   }
 }
if (Stack.empty()) {
     warn("symbol scopes are not balanced in " + File->getName());
     return;
   }
   SymbolScope S = Stack.pop_back_val();
   S.OpeningRecord->PtrEnd = CurOffset;
 }
 
 static void mergeSymbolRecords(BumpPtrAllocator &Alloc, ObjectFile *File,
-                               ArrayRef<TypeIndex> TypeIndexMap,
+                               const CVIndexMap &IndexMap,
                                BinaryStreamRef SymData) {
   // FIXME: Improve error recovery by warning and skipping records when
   // possible.
   CVSymbolArray Syms;
   BinaryStreamReader Reader(SymData);
   ExitOnErr(Reader.readArray(Syms, Reader.getLength()));
   SmallVector<SymbolScope, 4> Scopes;
   for (const CVSymbol &Sym : Syms) {
     // Discover type index references in the record. Skip it if we don't know
     // where they are.
     SmallVector<TiReference, 32> TypeRefs;
     if (!discoverTypeIndices(Sym, TypeRefs)) {
       log("ignoring unknown symbol record with kind 0x" + utohexstr(Sym.kind()));
       continue;
     }
 
     // Copy the symbol record so we can mutate it.
     MutableArrayRef<uint8_t> NewData = copySymbolForPdb(Sym, Alloc);
 
     // Re-map all the type index references.
     MutableArrayRef<uint8_t> Contents =
         NewData.drop_front(sizeof(RecordPrefix));
-    remapTypesInSymbolRecord(File, Contents, TypeIndexMap, TypeRefs);
+    remapTypesInSymbolRecord(File, Contents, IndexMap, TypeRefs);
 
     // Fill in "Parent" and "End" fields by maintaining a stack of scopes.
     CVSymbol NewSym(Sym.kind(), NewData);
     if (symbolOpensScope(Sym.kind()))
       scopeStackOpen(Scopes, File->ModuleDBI->getNextSymbolOffset(), NewSym);
     else if (symbolEndsScope(Sym.kind()))
       scopeStackClose(Scopes, File->ModuleDBI->getNextSymbolOffset(), File);
 
void PDBLinker::addObjectFile(ObjectFile *File) {
 
   File->ModuleDBI = &ExitOnErr(Builder.getDbiBuilder().addModuleInfo(Name));
   File->ModuleDBI->setObjFileName(Path);
 
   // Before we can process symbol substreams from .debug$S, we need to process
   // type information, file checksums, and the string table.  Add type info to
   // the PDB first, so that we can get the map from object file type and item
   // indices to PDB type and item indices.
-  SmallVector<TypeIndex, 128> TypeIndexMap;
-  mergeDebugT(File, TypeIndexMap);
+  CVIndexMap ObjectIndexMap;
+  const CVIndexMap &IndexMap = mergeDebugT(File, ObjectIndexMap);
 
   // Now do all live .debug$S sections.
   for (SectionChunk *DebugChunk : File->getDebugChunks()) {
     if (!DebugChunk->isLive() || DebugChunk->getSectionName() != ".debug$S")
       continue;
 
     ArrayRef<uint8_t> RelocatedDebugContents =
         relocateDebugChunk(Alloc, DebugChunk);
for (const DebugSubsectionRecord &SS : Subsections) {
         ExitOnErr(Checksums.initialize(SS.getRecordData()));
         break;
       case DebugSubsectionKind::Lines:
         // We can add the relocated line table directly to the PDB without
         // modification because the file checksum offsets will stay the same.
         File->ModuleDBI->addDebugSubsection(SS);
         break;
       case DebugSubsectionKind::Symbols:
-        mergeSymbolRecords(Alloc, File, TypeIndexMap, SS.getRecordData());
+        mergeSymbolRecords(Alloc, File, IndexMap, SS.getRecordData());
         break;
       default:
         // FIXME: Process the rest of the subsections.
         break;
       }
     }
 
     if (Checksums.valid()) {

lld/trunk/test/COFF/Inputs/pdb-type-server-simple-a.yaml

+--- !COFF
+header:
+  Machine:         IMAGE_FILE_MACHINE_AMD64
+  Characteristics: [  ]
+sections:
+  - Name:            .drectve
+    Characteristics: [ IMAGE_SCN_LNK_INFO, IMAGE_SCN_LNK_REMOVE ]
+    Alignment:       1
+    SectionData:     2020202F44454641554C544C49423A224C4942434D5422202F44454641554C544C49423A224F4C444E414D45532220
+  - Name:            '.debug$S'
+    Characteristics: [ IMAGE_SCN_CNT_INITIALIZED_DATA, IMAGE_SCN_MEM_DISCARDABLE, IMAGE_SCN_MEM_READ ]
+    Alignment:       1
+    Subsections:
+      - !Symbols
+        Records:
+          - Kind:            S_OBJNAME
+            ObjNameSym:
+              Signature:       0
+              ObjectName:      'C:\src\llvm-project\build\a.obj'
+          - Kind:            S_COMPILE3
+            Compile3Sym:
+              Flags:           [ SecurityChecks, HotPatch ]
+              Machine:         X64
+              FrontendMajor:   19
+              FrontendMinor:   0
+              FrontendBuild:   24215
+              FrontendQFE:     1
+              BackendMajor:    19
+              BackendMinor:    0
+              BackendBuild:    24215
+              BackendQFE:      1
+              Version:         'Microsoft (R) Optimizing Compiler'
+      - !Symbols
+        Records:
+          - Kind:            S_GPROC32_ID
+            ProcSym:
+              CodeSize:        27
+              DbgStart:        4
+              DbgEnd:          22
+              FunctionType:    4098
+              Flags:           [  ]
+              DisplayName:     main
+          - Kind:            S_FRAMEPROC
+            FrameProcSym:
+              TotalFrameBytes: 56
+              PaddingFrameBytes: 0
+              OffsetToPadding: 0
+              BytesOfCalleeSavedRegisters: 0
+              OffsetOfExceptionHandler: 0
+              SectionIdOfExceptionHandler: 0
+              Flags:           [ AsynchronousExceptionHandling, OptimizedForSpeed ]
+          - Kind:            S_REGREL32
+            RegRelativeSym:
+              Offset:          32
+              Type:            4102
+              Register:        RSP
+              VarName:         f
+          - Kind:            S_PROC_ID_END
+            ScopeEndSym:
+      - !Lines
+        CodeSize:        27
+        Flags:           [  ]
+        RelocOffset:     0
+        RelocSegment:    0
+        Blocks:
+          - FileName:        'c:\src\llvm-project\build\a.c'
+            Lines:
+              - Offset:          0
+                LineStart:       3
+                IsStatement:     true
+                EndDelta:        0
+              - Offset:          4
+                LineStart:       4
+                IsStatement:     true
+                EndDelta:        0
+              - Offset:          12
+                LineStart:       5
+                IsStatement:     true
+                EndDelta:        0
+              - Offset:          22
+                LineStart:       6
+                IsStatement:     true
+                EndDelta:        0
+            Columns:
+      - !Symbols
+        Records:
+          - Kind:            S_UDT
+            UDTSym:
+              Type:            4102
+              UDTName:         Foo
+      - !FileChecksums
+        Checksums:
+          - FileName:        'c:\src\llvm-project\build\a.c'
+            Kind:            MD5
+            Checksum:        BF69E7E933074E1B7ED1FE8FB395965B
+      - !StringTable
+        Strings:
+          - 'c:\src\llvm-project\build\a.c'
+      - !Symbols
+        Records:
+          - Kind:            S_BUILDINFO
+            BuildInfoSym:
+              BuildId:         4107
+    Relocations:
+      - VirtualAddress:  152
+        SymbolName:      main
+        Type:            IMAGE_REL_AMD64_SECREL
+      - VirtualAddress:  156
+        SymbolName:      main
+        Type:            IMAGE_REL_AMD64_SECTION
+      - VirtualAddress:  224
+        SymbolName:      main
+        Type:            IMAGE_REL_AMD64_SECREL
+      - VirtualAddress:  228
+        SymbolName:      main
+        Type:            IMAGE_REL_AMD64_SECTION
+  - Name:            '.debug$T'
+    Characteristics: [ IMAGE_SCN_CNT_INITIALIZED_DATA, IMAGE_SCN_MEM_DISCARDABLE, IMAGE_SCN_MEM_READ ]
+    Alignment:       1
+    Types:
+      - Kind:            LF_TYPESERVER2
+        TypeServer2:
+          Guid:            '{41414141-4141-4141-4141-414141414141}'
+          Age:             1
+          Name:            'C:\src\llvm-project\build\ts.pdb'
+  - Name:            '.text$mn'
+    Characteristics: [ IMAGE_SCN_CNT_CODE, IMAGE_SCN_MEM_EXECUTE, IMAGE_SCN_MEM_READ ]
+    Alignment:       16
+    SectionData:     4883EC38C74424202A000000488D4C2420E8000000004883C438C3
+    Relocations:
+      - VirtualAddress:  18
+        SymbolName:      g
+        Type:            IMAGE_REL_AMD64_REL32
+  - Name:            .xdata
+    Characteristics: [ IMAGE_SCN_CNT_INITIALIZED_DATA, IMAGE_SCN_MEM_READ ]
+    Alignment:       4
+    SectionData:     '0104010004620000'
+  - Name:            .pdata
+    Characteristics: [ IMAGE_SCN_CNT_INITIALIZED_DATA, IMAGE_SCN_MEM_READ ]
+    Alignment:       4
+    SectionData:     000000001B00000000000000
+    Relocations:
+      - VirtualAddress:  0
+        SymbolName:      '$LN3'
+        Type:            IMAGE_REL_AMD64_ADDR32NB
+      - VirtualAddress:  4
+        SymbolName:      '$LN3'
+        Type:            IMAGE_REL_AMD64_ADDR32NB
+      - VirtualAddress:  8
+        SymbolName:      '$unwind$main'
+        Type:            IMAGE_REL_AMD64_ADDR32NB
+symbols:
+  - Name:            .drectve
+    Value:           0
+    SectionNumber:   1
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    SectionDefinition:
+      Length:          47
+      NumberOfRelocations: 0
+      NumberOfLinenumbers: 0
+      CheckSum:        0
+      Number:          0
+  - Name:            '.debug$S'
+    Value:           0
+    SectionNumber:   2
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    SectionDefinition:
+      Length:          388
+      NumberOfRelocations: 4
+      NumberOfLinenumbers: 0
+      CheckSum:        0
+      Number:          0
+  - Name:            '.debug$T'
+    Value:           0
+    SectionNumber:   3
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    SectionDefinition:
+      Length:          64
+      NumberOfRelocations: 0
+      NumberOfLinenumbers: 0
+      CheckSum:        0
+      Number:          0
+  - Name:            '.text$mn'
+    Value:           0
+    SectionNumber:   4
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    SectionDefinition:
+      Length:          27
+      NumberOfRelocations: 1
+      NumberOfLinenumbers: 0
+      CheckSum:        1939996292
+      Number:          0
+  - Name:            g
+    Value:           0
+    SectionNumber:   0
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_FUNCTION
+    StorageClass:    IMAGE_SYM_CLASS_EXTERNAL
+  - Name:            main
+    Value:           0
+    SectionNumber:   4
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_FUNCTION
+    StorageClass:    IMAGE_SYM_CLASS_EXTERNAL
+  - Name:            '$LN3'
+    Value:           0
+    SectionNumber:   4
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_LABEL
+  - Name:            .xdata
+    Value:           0
+    SectionNumber:   5
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    SectionDefinition:
+      Length:          8
+      NumberOfRelocations: 0
+      NumberOfLinenumbers: 0
+      CheckSum:        931692337
+      Number:          0
+  - Name:            '$unwind$main'
+    Value:           0
+    SectionNumber:   5
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+  - Name:            .pdata
+    Value:           0
+    SectionNumber:   6
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    SectionDefinition:
+      Length:          12
+      NumberOfRelocations: 3
+      NumberOfLinenumbers: 0
+      CheckSum:        567356797
+      Number:          0
+  - Name:            '$pdata$main'
+    Value:           0
+    SectionNumber:   6
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+...

lld/trunk/test/COFF/Inputs/pdb-type-server-simple-b.yaml

+--- !COFF
+header:
+  Machine:         IMAGE_FILE_MACHINE_AMD64
+  Characteristics: [  ]
+sections:
+  - Name:            .drectve
+    Characteristics: [ IMAGE_SCN_LNK_INFO, IMAGE_SCN_LNK_REMOVE ]
+    Alignment:       1
+    SectionData:     2020202F44454641554C544C49423A224C4942434D5422202F44454641554C544C49423A224F4C444E414D45532220
+  - Name:            '.debug$S'
+    Characteristics: [ IMAGE_SCN_CNT_INITIALIZED_DATA, IMAGE_SCN_MEM_DISCARDABLE, IMAGE_SCN_MEM_READ ]
+    Alignment:       1
+    Subsections:
+      - !Symbols
+        Records:
+          - Kind:            S_OBJNAME
+            ObjNameSym:
+              Signature:       0
+              ObjectName:      'C:\src\llvm-project\build\b.obj'
+          - Kind:            S_COMPILE3
+            Compile3Sym:
+              Flags:           [ SecurityChecks, HotPatch ]
+              Machine:         X64
+              FrontendMajor:   19
+              FrontendMinor:   0
+              FrontendBuild:   24215
+              FrontendQFE:     1
+              BackendMajor:    19
+              BackendMinor:    0
+              BackendBuild:    24215
+              BackendQFE:      1
+              Version:         'Microsoft (R) Optimizing Compiler'
+      - !Symbols
+        Records:
+          - Kind:            S_GPROC32_ID
+            ProcSym:
+              CodeSize:        13
+              DbgStart:        5
+              DbgEnd:          12
+              FunctionType:    4099
+              Flags:           [  ]
+              DisplayName:     g
+          - Kind:            S_FRAMEPROC
+            FrameProcSym:
+              TotalFrameBytes: 0
+              PaddingFrameBytes: 0
+              OffsetToPadding: 0
+              BytesOfCalleeSavedRegisters: 0
+              OffsetOfExceptionHandler: 0
+              SectionIdOfExceptionHandler: 0
+              Flags:           [ AsynchronousExceptionHandling, OptimizedForSpeed ]
+          - Kind:            S_REGREL32
+            RegRelativeSym:
+              Offset:          8
+              Type:            4097
+              Register:        RSP
+              VarName:         p
+          - Kind:            S_PROC_ID_END
+            ScopeEndSym:
+      - !Lines
+        CodeSize:        13
+        Flags:           [  ]
+        RelocOffset:     0
+        RelocSegment:    0
+        Blocks:
+          - FileName:        'c:\src\llvm-project\build\b.c'
+            Lines:
+              - Offset:          0
+                LineStart:       2
+                IsStatement:     true
+                EndDelta:        0
+            Columns:
+      - !Symbols
+        Records:
+          - Kind:            S_UDT
+            UDTSym:
+              Type:            4102
+              UDTName:         Foo
+      - !FileChecksums
+        Checksums:
+          - FileName:        'c:\src\llvm-project\build\b.c'
+            Kind:            MD5
+            Checksum:        DDF8FD35CD67990C5D4147516BE10D0C
+      - !StringTable
+        Strings:
+          - 'c:\src\llvm-project\build\b.c'
+      - !Symbols
+        Records:
+          - Kind:            S_BUILDINFO
+            BuildInfoSym:
+              BuildId:         4111
+    Relocations:
+      - VirtualAddress:  152
+        SymbolName:      g
+        Type:            IMAGE_REL_AMD64_SECREL
+      - VirtualAddress:  156
+        SymbolName:      g
+        Type:            IMAGE_REL_AMD64_SECTION
+      - VirtualAddress:  220
+        SymbolName:      g
+        Type:            IMAGE_REL_AMD64_SECREL
+      - VirtualAddress:  224
+        SymbolName:      g
+        Type:            IMAGE_REL_AMD64_SECTION
+  - Name:            '.debug$T'
+    Characteristics: [ IMAGE_SCN_CNT_INITIALIZED_DATA, IMAGE_SCN_MEM_DISCARDABLE, IMAGE_SCN_MEM_READ ]
+    Alignment:       1
+    Types:
+      - Kind:            LF_TYPESERVER2
+        TypeServer2:
+          Guid:            '{41414141-4141-4141-4141-414141414141}'
+          Age:             1
+          Name:            'C:\src\llvm-project\build\ts.pdb'
+  - Name:            '.text$mn'
+    Characteristics: [ IMAGE_SCN_CNT_CODE, IMAGE_SCN_MEM_EXECUTE, IMAGE_SCN_MEM_READ ]
+    Alignment:       16
+    SectionData:     48894C2408488B4424088B00C3
+symbols:
+  - Name:            .drectve
+    Value:           0
+    SectionNumber:   1
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    SectionDefinition:
+      Length:          47
+      NumberOfRelocations: 0
+      NumberOfLinenumbers: 0
+      CheckSum:        0
+      Number:          0
+  - Name:            '.debug$S'
+    Value:           0
+    SectionNumber:   2
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    SectionDefinition:
+      Length:          360
+      NumberOfRelocations: 4
+      NumberOfLinenumbers: 0
+      CheckSum:        0
+      Number:          0
+  - Name:            '.debug$T'
+    Value:           0
+    SectionNumber:   3
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    SectionDefinition:
+      Length:          64
+      NumberOfRelocations: 0
+      NumberOfLinenumbers: 0
+      CheckSum:        0
+      Number:          0
+  - Name:            '.text$mn'
+    Value:           0
+    SectionNumber:   4
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_NULL
+    StorageClass:    IMAGE_SYM_CLASS_STATIC
+    SectionDefinition:
+      Length:          13
+      NumberOfRelocations: 0
+      NumberOfLinenumbers: 0
+      CheckSum:        3246683207
+      Number:          0
+  - Name:            g
+    Value:           0
+    SectionNumber:   4
+    SimpleType:      IMAGE_SYM_TYPE_NULL
+    ComplexType:     IMAGE_SYM_DTYPE_FUNCTION
+    StorageClass:    IMAGE_SYM_CLASS_EXTERNAL
+...

lld/trunk/test/COFF/Inputs/pdb-type-server-simple-ts.yaml

+---
+MSF:
+  SuperBlock:
+    BlockSize:       4096
+    FreeBlockMap:    1
+    NumBlocks:       19
+    NumDirectoryBytes: 64
+    Unknown1:        0
+    BlockMapAddr:    17
+  NumDirectoryBlocks: 1
+  DirectoryBlocks: [ 16 ]
+  NumStreams:      0
+  FileSize:        77824
+PdbStream:
+  Age:             1
+  Guid:            '{41414141-4141-4141-4141-414141414141}'
+  Signature:       1500053944
+  Features:        [ VC140 ]
+  Version:         VC70
+TpiStream:
+  Version:         VC80
+  Records:
+    - Kind:            LF_STRUCTURE
+      Class:
+        MemberCount:     0
+        Options:         [ None, ForwardReference, HasUniqueName ]
+        FieldList:       0
+        Name:            Foo
+        UniqueName:      '.?AUFoo@@'
+        DerivationList:  0
+        VTableShape:     0
+        Size:            0
+    - Kind:            LF_POINTER
+      Pointer:
+        ReferentType:    4096
+        Attrs:           65548
+    - Kind:            LF_ARGLIST
+      ArgList:
+        ArgIndices:      [ 4097 ]
+    - Kind:            LF_PROCEDURE
+      Procedure:
+        ReturnType:      116
+        CallConv:        NearC
+        Options:         [ None ]
+        ParameterCount:  1
+        ArgumentList:    4098
+    - Kind:            LF_POINTER
+      Pointer:
+        ReferentType:    4099
+        Attrs:           65548
+    - Kind:            LF_FIELDLIST
+      FieldList:
+        - Kind:            LF_MEMBER
+          DataMember:
+            Attrs:           3
+            Type:            116
+            FieldOffset:     0
+            Name:            x
+    - Kind:            LF_STRUCTURE
+      Class:
+        MemberCount:     1
+        Options:         [ None, HasUniqueName ]
+        FieldList:       4101
+        Name:            Foo
+        UniqueName:      '.?AUFoo@@'
+        DerivationList:  0
+        VTableShape:     0
+        Size:            4
+    - Kind:            LF_ARGLIST
+      ArgList:
+        ArgIndices:      [ 0 ]
+    - Kind:            LF_PROCEDURE
+      Procedure:
+        ReturnType:      116
+        CallConv:        NearC
+        Options:         [ None ]
+        ParameterCount:  0
+        ArgumentList:    4103
+IpiStream:
+  Version:         VC80
+  Records:
+    - Kind:            LF_STRING_ID
+      StringId:
+        Id:              0
+        String:          'c:\src\llvm-project\build\a.c'
+    - Kind:            LF_UDT_SRC_LINE
+      UdtSourceLine:
+        UDT:             4102
+        SourceFile:      4096
+        LineNumber:      1
+    - Kind:            LF_FUNC_ID
+      FuncId:
+        ParentScope:     0
+        FunctionType:    4104
+        Name:            main
+    - Kind:            LF_FUNC_ID
+      FuncId:
+        ParentScope:     0
+        FunctionType:    4099
+        Name:            g
+    - Kind:            LF_STRING_ID
+      StringId:
+        Id:              0
+        String:          'C:\src\llvm-project\build'
+    - Kind:            LF_STRING_ID
+      StringId:
+        Id:              0
+        String:          'C:\PROGRA~2\MICROS~1.0\VC\Bin\amd64\cl.exe'
+    - Kind:            LF_STRING_ID
+      StringId:
+        Id:              0
+        String:          '-c -Zi -MT -IC:\PROGRA~2\MICROS~1.0\VC\include -IC:\PROGRA~2\MICROS~1.0\VC\atlmfc\include -IC:\PROGRA~2\WI3CF2~1\10\include\10.0.14393.0\ucrt -IC:\PROGRA~2\WI3CF2~1\10\include\10.0.14393.0\shared -IC:\PROGRA~2\WI3CF2~1\10\include\10.0.14393.0\um'
+    - Kind:            LF_SUBSTR_LIST
+      StringList:
+        StringIndices:   [ 4102 ]
+    - Kind:            LF_STRING_ID
+      StringId:
+        Id:              4103
+        String:          ' -IC:\PROGRA~2\WI3CF2~1\10\include\10.0.14393.0\winrt -TC -X'
+    - Kind:            LF_STRING_ID
+      StringId:
+        Id:              0
+        String:          a.c
+    - Kind:            LF_STRING_ID
+      StringId:
+        Id:              0
+        String:          'C:\src\llvm-project\build\ts.pdb'
+    - Kind:            LF_BUILDINFO
+      BuildInfo:
+        ArgIndices:      [ 4100, 4101, 4105, 4106, 4104 ]
+    - Kind:            LF_STRING_ID
+      StringId:
+        Id:              0
+        String:          'c:\src\llvm-project\build\b.c'
+    - Kind:            LF_UDT_SRC_LINE
+      UdtSourceLine:
+        UDT:             4102
+        SourceFile:      4108
+        LineNumber:      1
+    - Kind:            LF_STRING_ID
+      StringId:
+        Id:              0
+        String:          b.c
+    - Kind:            LF_BUILDINFO
+      BuildInfo:
+        ArgIndices:      [ 4100, 4101, 4110, 4106, 4104 ]
+...

lld/trunk/test/COFF/pdb-type-server-missing.yaml

 # This is an object compiled with /Zi (see the LF_TYPESERVER2 record) without an
 # adjacent type server PDB. Test that LLD fails gracefully on it.
 
-# FIXME: Type server handling was removed from LLVM.
-# XFAIL: *
-
 # FIXME: Ideally we'd do what MSVC does, which is to warn and drop all debug
 # info in the object with the missing PDB.
 
 # RUN: yaml2obj %s -o %t.obj
 # RUN: not lld-link %t.obj -out:%t.exe -debug -pdb:%t.pdb -nodefaultlib -entry:main 2>&1 | FileCheck %s
 
-# CHECK: error: {{.*}} Type server PDB was not found
+# CHECK: error: Type server PDB was not found
 
 --- !COFF
 header:
   Machine:         IMAGE_FILE_MACHINE_AMD64
   Characteristics: [  ]
 sections:
   - Name:            '.debug$S'
     Characteristics: [ IMAGE_SCN_CNT_INITIALIZED_DATA, IMAGE_SCN_MEM_DISCARDABLE, IMAGE_SCN_MEM_READ ]

lld/trunk/test/COFF/pdb-type-server-simple.test

+Replicate this scenario:
+
+$ cat a.c
+struct Foo { int x; };
+int g(struct Foo *p);
+int main() {
+  struct Foo f = {42};
+  return g(&f);
+}
+
+$ cat b.c
+struct Foo { int x; };
+int g(struct Foo *p) { return p->x; }
+
+$ cl -c a.c b.c -Zi -Fdts.pdb
+
+$ lld-link a.obj b.obj -debug -entry:main -nodefaultlib -out:t.exe
+
+RUN: rm -rf %t && mkdir -p %t && cd %t
+RUN: yaml2obj %S/Inputs/pdb-type-server-simple-a.yaml -o a.obj
+RUN: yaml2obj %S/Inputs/pdb-type-server-simple-b.yaml -o b.obj
+RUN: llvm-pdbutil yaml2pdb %S/Inputs/pdb-type-server-simple-ts.yaml -pdb ts.pdb
+RUN: lld-link a.obj b.obj -entry:main -debug -out:t.exe -pdb:t.pdb -nodefaultlib
+RUN: llvm-pdbutil dump -symbols -types -ids %t/t.pdb | FileCheck %s
+
+
+CHECK-LABEL: Types (TPI Stream)
+CHECK: ============================================================
+
+CHECK:   [[FOO_DECL:[^ ]*]] | LF_STRUCTURE [size = 36] `Foo`
+
+CHECK:   [[FOO_PTR:[^ ]*]] | LF_POINTER [size = 12]
+CHECK-NEXT:            referent = [[FOO_DECL]]
+
+CHECK:   [[G_ARGS:[^ ]*]] | LF_ARGLIST [size = 12]
+CHECK-NEXT:            [[FOO_PTR]]: `Foo*`
+
+CHECK:   [[G_PROTO:[^ ]*]] | LF_PROCEDURE [size = 16]
+CHECK-NEXT:       return type = 0x0074 (int), # args = 1, param list = [[G_ARGS]]
+CHECK-NEXT:       calling conv = cdecl, options = None
+
+CHECK:   [[FOO_COMPLETE:[^ ]*]] | LF_STRUCTURE [size = 36] `Foo`
+CHECK-NEXT:       unique name: `.?AUFoo@@`
+CHECK-NEXT:       vtable: <no type>, base list: <no type>, field list: 0x{{.*}}
+CHECK:            options: has unique name
+CHECK:   [[MAIN_PROTO:[^ ]*]] | LF_PROCEDURE [size = 16]
+CHECK:            return type = 0x0074 (int), # args = 0, param list = 0x{{.*}}
+CHECK:            calling conv = cdecl, options = None
+
+
+CHECK-LABEL:                      Types (IPI Stream)
+CHECK: ============================================================
+CHECK:   [[MAIN_ID:[^ ]*]] | LF_FUNC_ID [size = 20]
+CHECK:            name = main, type = [[MAIN_PROTO]], parent scope = <no type>
+CHECK:   [[G_ID:[^ ]*]] | LF_FUNC_ID [size = 16]
+CHECK:            name = g, type = [[G_PROTO]], parent scope = <no type>
+CHECK:   [[A_BUILD:[^ ]*]] | LF_BUILDINFO [size = 28]
+CHECK:            {{.*}}: `a.c`
+CHECK:   [[B_BUILD:[^ ]*]] | LF_BUILDINFO [size = 28]
+CHECK:            {{.*}}: `b.c`
+
+CHECK-LABEL:                           Symbols
+CHECK: ============================================================
+CHECK-LABEL:   Mod 0000 | `{{.*}}a.obj`:
+CHECK:        4 | S_OBJNAME [size = 40] sig=0, `C:\src\llvm-project\build\a.obj`
+CHECK:      104 | S_GPROC32_ID [size = 44] `main`
+CHECK:            parent = 0, end = 196, addr = 0002:0000, code size = 27
+CHECK:            type = {{.*}}, debug start = 4, debug end = 22, flags = none
+CHECK:      200 | S_UDT [size = 12] `Foo`
+CHECK:            original type = [[FOO_COMPLETE]]
+CHECK:      212 | S_BUILDINFO [size = 8] BuildId = `[[A_BUILD]]`
+CHECK-LABEL:   Mod 0001 | `{{.*}}b.obj`:
+CHECK:        4 | S_OBJNAME [size = 40] sig=0, `C:\src\llvm-project\build\b.obj`
+CHECK:       44 | S_COMPILE3 [size = 60]
+CHECK:            machine = intel x86-x64, Ver = Microsoft (R) Optimizing Compiler, language = c
+CHECK:            frontend = 19.0.24215.1, backend = 19.0.24215.1
+CHECK:            flags = security checks | hot patchable
+CHECK:      104 | S_GPROC32_ID [size = 44] `g`
+CHECK:            parent = 0, end = 196, addr = 0002:0032, code size = 13
+CHECK:            type = {{.*}}, debug start = 5, debug end = 12, flags = none
+CHECK:      148 | S_FRAMEPROC [size = 32]
+CHECK:            size = 0, padding size = 0, offset to padding = 0
+CHECK:            bytes of callee saved registers = 0, exception handler addr = 0000:0000
+CHECK:            flags = has async eh | opt speed
+CHECK:      180 | S_REGREL32 [size = 16] `p`
+CHECK:            type = [[FOO_PTR]] (Foo*), register = rsp, offset = 8
+CHECK:      196 | S_END [size = 4]
+CHECK:      200 | S_UDT [size = 12] `Foo`
+CHECK:            original type = [[FOO_COMPLETE]]
+CHECK:      212 | S_BUILDINFO [size = 8] BuildId = `[[B_BUILD]]`
+CHECK-LABEL:   Mod 0002 | `* Linker *`:

llvm/trunk/include/llvm/DebugInfo/CodeView/GUID.h

 struct GUID {
   uint8_t Guid[16];
 };
 
 inline bool operator==(const GUID &LHS, const GUID &RHS) {
   return 0 == ::memcmp(LHS.Guid, RHS.Guid, sizeof(LHS.Guid));
 }
 
+inline bool operator<(const GUID &LHS, const GUID &RHS) {
+  return ::memcmp(LHS.Guid, RHS.Guid, sizeof(LHS.Guid)) < 0;
+}
+
+inline bool operator<=(const GUID &LHS, const GUID &RHS) {
+  return ::memcmp(LHS.Guid, RHS.Guid, sizeof(LHS.Guid)) <= 0;
+}
+
+inline bool operator>(const GUID &LHS, const GUID &RHS) {
+  return !(LHS <= RHS);
+}
+
+inline bool operator>=(const GUID &LHS, const GUID &RHS) {
+  return !(LHS < RHS);
+}
+
+inline bool operator!=(const GUID &LHS, const GUID &RHS) {
+  return !(LHS == RHS);
+}
+
 raw_ostream &operator<<(raw_ostream &OS, const GUID &Guid);
 
 } // namespace codeview
 } // namespace llvm
 
 #endif