contrib/llvm/lib/DebugInfo/PDB/Native/TpiStreamBuilder.cpp

   1 //===- TpiStreamBuilder.cpp -   -------------------------------------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 #include "llvm/DebugInfo/PDB/Native/TpiStreamBuilder.h"
  11 #include "llvm/ADT/ArrayRef.h"
  12 #include "llvm/ADT/STLExtras.h"
  13 #include "llvm/DebugInfo/CodeView/TypeIndex.h"
  14 #include "llvm/DebugInfo/CodeView/TypeRecord.h"
  15 #include "llvm/DebugInfo/MSF/MSFBuilder.h"
  16 #include "llvm/DebugInfo/MSF/MappedBlockStream.h"
  17 #include "llvm/DebugInfo/PDB/Native/PDBFile.h"
  18 #include "llvm/DebugInfo/PDB/Native/RawError.h"
  19 #include "llvm/DebugInfo/PDB/Native/RawTypes.h"
  20 #include "llvm/Support/Allocator.h"
  21 #include "llvm/Support/BinaryByteStream.h"
  22 #include "llvm/Support/BinaryStreamArray.h"
  23 #include "llvm/Support/BinaryStreamReader.h"
  24 #include "llvm/Support/BinaryStreamWriter.h"
  25 #include "llvm/Support/Endian.h"
  26 #include "llvm/Support/Error.h"
  27 #include <algorithm>
  28 #include <cstdint>
  29
  30 using namespace llvm;
  31 using namespace llvm::msf;
  32 using namespace llvm::pdb;
  33 using namespace llvm::support;
  34
  35 TpiStreamBuilder::TpiStreamBuilder(MSFBuilder &Msf, uint32_t StreamIdx)
  36     : Msf(Msf), Allocator(Msf.getAllocator()), Header(nullptr), Idx(StreamIdx) {
  37 }
  38
  39 TpiStreamBuilder::~TpiStreamBuilder() = default;
  40
  41 void TpiStreamBuilder::setVersionHeader(PdbRaw_TpiVer Version) {
  42   VerHeader = Version;
  43 }
  44
  45 void TpiStreamBuilder::addTypeRecord(ArrayRef<uint8_t> Record,
  46                                      Optional<uint32_t> Hash) {
  47   // If we just crossed an 8KB threshold, add a type index offset.
  48   size_t NewSize = TypeRecordBytes + Record.size();
  49   constexpr size_t EightKB = 8 * 1024;
  50   if (NewSize / EightKB > TypeRecordBytes / EightKB || TypeRecords.empty()) {
  51     TypeIndexOffsets.push_back(
  52         {codeview::TypeIndex(codeview::TypeIndex::FirstNonSimpleIndex +
  53                              TypeRecords.size()),
  54          ulittle32_t(TypeRecordBytes)});
  55   }
  56   TypeRecordBytes = NewSize;
  57
  58   TypeRecords.push_back(Record);
  59   if (Hash)
  60     TypeHashes.push_back(*Hash);
  61 }
  62
  63 Error TpiStreamBuilder::finalize() {
  64   if (Header)
  65     return Error::success();
  66
  67   TpiStreamHeader *H = Allocator.Allocate<TpiStreamHeader>();
  68
  69   uint32_t Count = TypeRecords.size();
  70
  71   H->Version = VerHeader;
  72   H->HeaderSize = sizeof(TpiStreamHeader);
  73   H->TypeIndexBegin = codeview::TypeIndex::FirstNonSimpleIndex;
  74   H->TypeIndexEnd = H->TypeIndexBegin + Count;
  75   H->TypeRecordBytes = TypeRecordBytes;
  76
  77   H->HashStreamIndex = HashStreamIndex;
  78   H->HashAuxStreamIndex = kInvalidStreamIndex;
  79   H->HashKeySize = sizeof(ulittle32_t);
  80   H->NumHashBuckets = MinTpiHashBuckets;
  81
  82   // Recall that hash values go into a completely different stream identified by
  83   // the `HashStreamIndex` field of the `TpiStreamHeader`.  Therefore, the data
  84   // begins at offset 0 of this independent stream.
  85   H->HashValueBuffer.Off = 0;
  86   H->HashValueBuffer.Length = calculateHashBufferSize();
  87
  88   // We never write any adjustments into our PDBs, so this is usually some
  89   // offset with zero length.
  90   H->HashAdjBuffer.Off = H->HashValueBuffer.Off + H->HashValueBuffer.Length;
  91   H->HashAdjBuffer.Length = 0;
  92
  93   H->IndexOffsetBuffer.Off = H->HashAdjBuffer.Off + H->HashAdjBuffer.Length;
  94   H->IndexOffsetBuffer.Length = calculateIndexOffsetSize();
  95
  96   Header = H;
  97   return Error::success();
  98 }
  99
 100 uint32_t TpiStreamBuilder::calculateSerializedLength() {
 101   return sizeof(TpiStreamHeader) + TypeRecordBytes;
 102 }
 103
 104 uint32_t TpiStreamBuilder::calculateHashBufferSize() const {
 105   assert((TypeRecords.size() == TypeHashes.size() || TypeHashes.empty()) &&
 106          "either all or no type records should have hashes");
 107   return TypeHashes.size() * sizeof(ulittle32_t);
 108 }
 109
 110 uint32_t TpiStreamBuilder::calculateIndexOffsetSize() const {
 111   return TypeIndexOffsets.size() * sizeof(codeview::TypeIndexOffset);
 112 }
 113
 114 Error TpiStreamBuilder::finalizeMsfLayout() {
 115   uint32_t Length = calculateSerializedLength();
 116   if (auto EC = Msf.setStreamSize(Idx, Length))
 117     return EC;
 118
 119   uint32_t HashStreamSize =
 120       calculateHashBufferSize() + calculateIndexOffsetSize();
 121
 122   if (HashStreamSize == 0)
 123     return Error::success();
 124
 125   auto ExpectedIndex = Msf.addStream(HashStreamSize);
 126   if (!ExpectedIndex)
 127     return ExpectedIndex.takeError();
 128   HashStreamIndex = *ExpectedIndex;
 129   if (!TypeHashes.empty()) {
 130     ulittle32_t *H = Allocator.Allocate<ulittle32_t>(TypeHashes.size());
 131     MutableArrayRef<ulittle32_t> HashBuffer(H, TypeHashes.size());
 132     for (uint32_t I = 0; I < TypeHashes.size(); ++I) {
 133       HashBuffer[I] = TypeHashes[I] % MinTpiHashBuckets;
 134     }
 135     ArrayRef<uint8_t> Bytes(
 136         reinterpret_cast<const uint8_t *>(HashBuffer.data()),
 137         calculateHashBufferSize());
 138     HashValueStream =
 139         llvm::make_unique<BinaryByteStream>(Bytes, llvm::support::little);
 140   }
 141   return Error::success();
 142 }
 143
 144 Error TpiStreamBuilder::commit(const msf::MSFLayout &Layout,
 145                                WritableBinaryStreamRef Buffer) {
 146   if (auto EC = finalize())
 147     return EC;
 148
 149   auto InfoS = WritableMappedBlockStream::createIndexedStream(Layout, Buffer,
 150                                                               Idx, Allocator);
 151
 152   BinaryStreamWriter Writer(*InfoS);
 153   if (auto EC = Writer.writeObject(*Header))
 154     return EC;
 155
 156   for (auto Rec : TypeRecords)
 157     if (auto EC = Writer.writeBytes(Rec))
 158       return EC;
 159
 160   if (HashStreamIndex != kInvalidStreamIndex) {
 161     auto HVS = WritableMappedBlockStream::createIndexedStream(
 162         Layout, Buffer, HashStreamIndex, Allocator);
 163     BinaryStreamWriter HW(*HVS);
 164     if (HashValueStream) {
 165       if (auto EC = HW.writeStreamRef(*HashValueStream))
 166         return EC;
 167     }
 168
 169     for (auto &IndexOffset : TypeIndexOffsets) {
 170       if (auto EC = HW.writeObject(IndexOffset))
 171         return EC;
 172     }
 173   }
 174
 175   return Error::success();
 176 }