include/llvm/DebugInfo/CodeView/SymbolDeserializer.h

   1 //===- SymbolDeserializer.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_SYMBOLDESERIALIZER_H
  10 #define LLVM_DEBUGINFO_CODEVIEW_SYMBOLDESERIALIZER_H
  11
  12 #include "llvm/ADT/ArrayRef.h"
  13 #include "llvm/DebugInfo/CodeView/SymbolRecord.h"
  14 #include "llvm/DebugInfo/CodeView/SymbolRecordMapping.h"
  15 #include "llvm/DebugInfo/CodeView/SymbolVisitorCallbacks.h"
  16 #include "llvm/DebugInfo/CodeView/SymbolVisitorDelegate.h"
  17 #include "llvm/Support/BinaryByteStream.h"
  18 #include "llvm/Support/BinaryStreamReader.h"
  19 #include "llvm/Support/Error.h"
  20
  21 namespace llvm {
  22 namespace codeview {
  23 class SymbolVisitorDelegate;
  24 class SymbolDeserializer : public SymbolVisitorCallbacks {
  25   struct MappingInfo {
  26     MappingInfo(ArrayRef<uint8_t> RecordData, CodeViewContainer Container)
  27         : Stream(RecordData, llvm::support::little), Reader(Stream),
  28           Mapping(Reader, Container) {}
  29
  30     BinaryByteStream Stream;
  31     BinaryStreamReader Reader;
  32     SymbolRecordMapping Mapping;
  33   };
  34
  35 public:
  36   template <typename T> static Error deserializeAs(CVSymbol Symbol, T &Record) {
  37     // If we're just deserializing one record, then don't worry about alignment
  38     // as there's nothing that comes after.
  39     SymbolDeserializer S(nullptr, CodeViewContainer::ObjectFile);
  40     if (auto EC = S.visitSymbolBegin(Symbol))
  41       return EC;
  42     if (auto EC = S.visitKnownRecord(Symbol, Record))
  43       return EC;
  44     if (auto EC = S.visitSymbolEnd(Symbol))
  45       return EC;
  46     return Error::success();
  47   }
  48   template <typename T> static Expected<T> deserializeAs(CVSymbol Symbol) {
  49     T Record(static_cast<SymbolRecordKind>(Symbol.kind()));
  50     if (auto EC = deserializeAs<T>(Symbol, Record))
  51       return std::move(EC);
  52     return Record;
  53   }
  54
  55   explicit SymbolDeserializer(SymbolVisitorDelegate *Delegate,
  56                               CodeViewContainer Container)
  57       : Delegate(Delegate), Container(Container) {}
  58
  59   Error visitSymbolBegin(CVSymbol &Record, uint32_t Offset) override {
  60     return visitSymbolBegin(Record);
  61   }
  62
  63   Error visitSymbolBegin(CVSymbol &Record) override {
  64     assert(!Mapping && "Already in a symbol mapping!");
  65     Mapping = std::make_unique<MappingInfo>(Record.content(), Container);
  66     return Mapping->Mapping.visitSymbolBegin(Record);
  67   }
  68   Error visitSymbolEnd(CVSymbol &Record) override {
  69     assert(Mapping && "Not in a symbol mapping!");
  70     auto EC = Mapping->Mapping.visitSymbolEnd(Record);
  71     Mapping.reset();
  72     return EC;
  73   }
  74
  75 #define SYMBOL_RECORD(EnumName, EnumVal, Name)                                 \
  76   Error visitKnownRecord(CVSymbol &CVR, Name &Record) override {               \
  77     return visitKnownRecordImpl(CVR, Record);                                  \
  78   }
  79 #define SYMBOL_RECORD_ALIAS(EnumName, EnumVal, Name, AliasName)
  80 #include "llvm/DebugInfo/CodeView/CodeViewSymbols.def"
  81
  82 private:
  83   template <typename T> Error visitKnownRecordImpl(CVSymbol &CVR, T &Record) {
  84
  85     Record.RecordOffset =
  86         Delegate ? Delegate->getRecordOffset(Mapping->Reader) : 0;
  87     if (auto EC = Mapping->Mapping.visitKnownRecord(CVR, Record))
  88       return EC;
  89     return Error::success();
  90   }
  91
  92   SymbolVisitorDelegate *Delegate;
  93   CodeViewContainer Container;
  94   std::unique_ptr<MappingInfo> Mapping;
  95 };
  96 }
  97 }
  98
  99 #endif