include/llvm/DebugInfo/CodeView/SymbolSerializer.h

   1 //===- SymbolSerializer.h ---------------------------------------*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #ifndef LLVM_DEBUGINFO_CODEVIEW_SYMBOLSERIALIZER_H
  10 #define LLVM_DEBUGINFO_CODEVIEW_SYMBOLSERIALIZER_H
  11
  12 #include "llvm/ADT/Optional.h"
  13 #include "llvm/DebugInfo/CodeView/CodeView.h"
  14 #include "llvm/DebugInfo/CodeView/RecordSerialization.h"
  15 #include "llvm/DebugInfo/CodeView/SymbolRecord.h"
  16 #include "llvm/DebugInfo/CodeView/SymbolRecordMapping.h"
  17 #include "llvm/DebugInfo/CodeView/SymbolVisitorCallbacks.h"
  18 #include "llvm/Support/Allocator.h"
  19 #include "llvm/Support/BinaryByteStream.h"
  20 #include "llvm/Support/BinaryStreamWriter.h"
  21 #include "llvm/Support/Error.h"
  22 #include <cstdint>
  23 #include <vector>
  24
  25 namespace llvm {
  26 namespace codeview {
  27
  28 class SymbolSerializer : public SymbolVisitorCallbacks {
  29   BumpPtrAllocator &Storage;
  30   // Since this is a fixed size buffer, use a stack allocated buffer.  This
  31   // yields measurable performance increase over the repeated heap allocations
  32   // when serializing many independent records via writeOneSymbol.
  33   std::array<uint8_t, MaxRecordLength> RecordBuffer;
  34   MutableBinaryByteStream Stream;
  35   BinaryStreamWriter Writer;
  36   SymbolRecordMapping Mapping;
  37   Optional<SymbolKind> CurrentSymbol;
  38
  39   Error writeRecordPrefix(SymbolKind Kind) {
  40     RecordPrefix Prefix;
  41     Prefix.RecordKind = Kind;
  42     Prefix.RecordLen = 0;
  43     if (auto EC = Writer.writeObject(Prefix))
  44       return EC;
  45     return Error::success();
  46   }
  47
  48 public:
  49   SymbolSerializer(BumpPtrAllocator &Storage, CodeViewContainer Container);
  50
  51   template <typename SymType>
  52   static CVSymbol writeOneSymbol(SymType &Sym, BumpPtrAllocator &Storage,
  53                                  CodeViewContainer Container) {
  54     RecordPrefix Prefix{uint16_t(Sym.Kind)};
  55     CVSymbol Result(&Prefix, sizeof(Prefix));
  56     SymbolSerializer Serializer(Storage, Container);
  57     consumeError(Serializer.visitSymbolBegin(Result));
  58     consumeError(Serializer.visitKnownRecord(Result, Sym));
  59     consumeError(Serializer.visitSymbolEnd(Result));
  60     return Result;
  61   }
  62
  63   Error visitSymbolBegin(CVSymbol &Record) override;
  64   Error visitSymbolEnd(CVSymbol &Record) override;
  65
  66 #define SYMBOL_RECORD(EnumName, EnumVal, Name)                                 \
  67   Error visitKnownRecord(CVSymbol &CVR, Name &Record) override {               \
  68     return visitKnownRecordImpl(CVR, Record);                                  \
  69   }
  70 #define SYMBOL_RECORD_ALIAS(EnumName, EnumVal, Name, AliasName)
  71 #include "llvm/DebugInfo/CodeView/CodeViewSymbols.def"
  72
  73 private:
  74   template <typename RecordKind>
  75   Error visitKnownRecordImpl(CVSymbol &CVR, RecordKind &Record) {
  76     return Mapping.visitKnownRecord(CVR, Record);
  77   }
  78 };
  79
  80 } // end namespace codeview
  81 } // end namespace llvm
  82
  83 #endif // LLVM_DEBUGINFO_CODEVIEW_SYMBOLSERIALIZER_H