contrib/llvm/include/llvm/DebugInfo/CodeView/TypeSerializer.h

   1 //===- TypeSerializer.h -----------------------------------------*- C++ -*-===//
   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 #ifndef LLVM_DEBUGINFO_CODEVIEW_TYPESERIALIZER_H
  11 #define LLVM_DEBUGINFO_CODEVIEW_TYPESERIALIZER_H
  12
  13 #include "llvm/DebugInfo/CodeView/TypeRecordMapping.h"
  14 #include "llvm/DebugInfo/CodeView/TypeVisitorCallbacks.h"
  15 #include "llvm/Support/BinaryByteStream.h"
  16 #include "llvm/Support/BinaryStreamWriter.h"
  17
  18 #include "llvm/ADT/Optional.h"
  19 #include "llvm/ADT/SmallVector.h"
  20 #include "llvm/ADT/StringMap.h"
  21 #include "llvm/ADT/StringRef.h"
  22 #include "llvm/Support/Allocator.h"
  23 #include "llvm/Support/Error.h"
  24
  25 namespace llvm {
  26
  27 namespace codeview {
  28
  29 class TypeSerializer : public TypeVisitorCallbacks {
  30   struct SubRecord {
  31     SubRecord(TypeLeafKind K, uint32_t S) : Kind(K), Size(S) {}
  32
  33     TypeLeafKind Kind;
  34     uint32_t Size = 0;
  35   };
  36   struct RecordSegment {
  37     SmallVector<SubRecord, 16> SubRecords;
  38
  39     uint32_t length() const {
  40       uint32_t L = sizeof(RecordPrefix);
  41       for (const auto &R : SubRecords) {
  42         L += R.Size;
  43       }
  44       return L;
  45     }
  46   };
  47
  48   typedef SmallVector<MutableArrayRef<uint8_t>, 2> RecordList;
  49
  50   static constexpr uint8_t ContinuationLength = 8;
  51   BumpPtrAllocator &RecordStorage;
  52   RecordSegment CurrentSegment;
  53   RecordList FieldListSegments;
  54
  55   TypeIndex LastTypeIndex;
  56   Optional<TypeLeafKind> TypeKind;
  57   Optional<TypeLeafKind> MemberKind;
  58   std::vector<uint8_t> RecordBuffer;
  59   MutableBinaryByteStream Stream;
  60   BinaryStreamWriter Writer;
  61   TypeRecordMapping Mapping;
  62
  63   RecordList SeenRecords;
  64   StringMap<TypeIndex> HashedRecords;
  65
  66   bool isInFieldList() const;
  67   TypeIndex calcNextTypeIndex() const;
  68   TypeIndex incrementTypeIndex();
  69   MutableArrayRef<uint8_t> getCurrentSubRecordData();
  70   MutableArrayRef<uint8_t> getCurrentRecordData();
  71   Error writeRecordPrefix(TypeLeafKind Kind);
  72   TypeIndex insertRecordBytesPrivate(MutableArrayRef<uint8_t> Record);
  73   TypeIndex insertRecordBytesWithCopy(CVType &Record,
  74                                       MutableArrayRef<uint8_t> Data);
  75
  76   Expected<MutableArrayRef<uint8_t>>
  77   addPadding(MutableArrayRef<uint8_t> Record);
  78
  79 public:
  80   explicit TypeSerializer(BumpPtrAllocator &Storage);
  81
  82   ArrayRef<MutableArrayRef<uint8_t>> records() const;
  83   TypeIndex getLastTypeIndex() const;
  84   TypeIndex insertRecordBytes(MutableArrayRef<uint8_t> Record);
  85   Expected<TypeIndex> visitTypeEndGetIndex(CVType &Record);
  86
  87   Error visitTypeBegin(CVType &Record) override;
  88   Error visitTypeEnd(CVType &Record) override;
  89   Error visitMemberBegin(CVMemberRecord &Record) override;
  90   Error visitMemberEnd(CVMemberRecord &Record) override;
  91
  92 #define TYPE_RECORD(EnumName, EnumVal, Name)                                   \
  93   virtual Error visitKnownRecord(CVType &CVR, Name##Record &Record) override { \
  94     return visitKnownRecordImpl(CVR, Record);                                  \
  95   }
  96 #define TYPE_RECORD_ALIAS(EnumName, EnumVal, Name, AliasName)
  97 #define MEMBER_RECORD(EnumName, EnumVal, Name)                                 \
  98   Error visitKnownMember(CVMemberRecord &CVR, Name##Record &Record) override { \
  99     return visitKnownMemberImpl<Name##Record>(CVR, Record);                    \
 100   }
 101 #define MEMBER_RECORD_ALIAS(EnumName, EnumVal, Name, AliasName)
 102 #include "llvm/DebugInfo/CodeView/TypeRecords.def"
 103
 104 private:
 105   template <typename RecordKind>
 106   Error visitKnownRecordImpl(CVType &CVR, RecordKind &Record) {
 107     return Mapping.visitKnownRecord(CVR, Record);
 108   }
 109
 110   template <typename RecordType>
 111   Error visitKnownMemberImpl(CVMemberRecord &CVR, RecordType &Record) {
 112     assert(CVR.Kind == static_cast<TypeLeafKind>(Record.getKind()));
 113
 114     if (auto EC = Writer.writeEnum(CVR.Kind))
 115       return EC;
 116
 117     if (auto EC = Mapping.visitKnownMember(CVR, Record))
 118       return EC;
 119
 120     // Get all the data that was just written and is yet to be committed to
 121     // the current segment.  Then pad it to 4 bytes.
 122     MutableArrayRef<uint8_t> ThisRecord = getCurrentSubRecordData();
 123     auto ExpectedRecord = addPadding(ThisRecord);
 124     if (!ExpectedRecord)
 125       return ExpectedRecord.takeError();
 126     ThisRecord = *ExpectedRecord;
 127
 128     CurrentSegment.SubRecords.emplace_back(CVR.Kind, ThisRecord.size());
 129     CVR.Data = ThisRecord;
 130
 131     // Both the last subrecord and the total length of this segment should be
 132     // multiples of 4.
 133     assert(ThisRecord.size() % 4 == 0);
 134     assert(CurrentSegment.length() % 4 == 0);
 135
 136     return Error::success();
 137   }
 138 };
 139 }
 140 }
 141
 142 #endif