llvm/lib/DebugInfo/CodeView/CVSymbolVisitor.cpp

   1 //===- CVSymbolVisitor.cpp --------------------------------------*- 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 #include "llvm/DebugInfo/CodeView/CVSymbolVisitor.h"
  10
  11 #include "llvm/DebugInfo/CodeView/CodeView.h"
  12 #include "llvm/DebugInfo/CodeView/SymbolRecordHelpers.h"
  13 #include "llvm/DebugInfo/CodeView/SymbolVisitorCallbacks.h"
  14 #include "llvm/Support/BinaryStreamArray.h"
  15
  16 using namespace llvm;
  17 using namespace llvm::codeview;
  18
  19 CVSymbolVisitor::CVSymbolVisitor(SymbolVisitorCallbacks &Callbacks)
  20     : Callbacks(Callbacks) {}
  21
  22 template <typename T>
  23 static Error visitKnownRecord(CVSymbol &Record,
  24                               SymbolVisitorCallbacks &Callbacks) {
  25   SymbolRecordKind RK = static_cast<SymbolRecordKind>(Record.kind());
  26   T KnownRecord(RK);
  27   if (auto EC = Callbacks.visitKnownRecord(Record, KnownRecord))
  28     return EC;
  29   return Error::success();
  30 }
  31
  32 static Error finishVisitation(CVSymbol &Record,
  33                               SymbolVisitorCallbacks &Callbacks) {
  34   switch (Record.kind()) {
  35   default:
  36     if (auto EC = Callbacks.visitUnknownSymbol(Record))
  37       return EC;
  38     break;
  39 #define SYMBOL_RECORD(EnumName, EnumVal, Name)                                 \
  40   case EnumName: {                                                             \
  41     if (auto EC = visitKnownRecord<Name>(Record, Callbacks))                   \
  42       return EC;                                                               \
  43     break;                                                                     \
  44   }
  45 #define SYMBOL_RECORD_ALIAS(EnumName, EnumVal, Name, AliasName)                \
  46   SYMBOL_RECORD(EnumVal, EnumVal, AliasName)
  47 #include "llvm/DebugInfo/CodeView/CodeViewSymbols.def"
  48   }
  49
  50   if (auto EC = Callbacks.visitSymbolEnd(Record))
  51     return EC;
  52
  53   return Error::success();
  54 }
  55
  56 Error CVSymbolVisitor::visitSymbolRecord(CVSymbol &Record) {
  57   if (auto EC = Callbacks.visitSymbolBegin(Record))
  58     return EC;
  59   return finishVisitation(Record, Callbacks);
  60 }
  61
  62 Error CVSymbolVisitor::visitSymbolRecord(CVSymbol &Record, uint32_t Offset) {
  63   if (auto EC = Callbacks.visitSymbolBegin(Record, Offset))
  64     return EC;
  65   return finishVisitation(Record, Callbacks);
  66 }
  67
  68 Error CVSymbolVisitor::visitSymbolStream(const CVSymbolArray &Symbols) {
  69   for (auto I : Symbols) {
  70     if (auto EC = visitSymbolRecord(I))
  71       return EC;
  72   }
  73   return Error::success();
  74 }
  75
  76 Error CVSymbolVisitor::visitSymbolStream(const CVSymbolArray &Symbols,
  77                                          uint32_t InitialOffset) {
  78   for (auto I : Symbols) {
  79     if (auto EC = visitSymbolRecord(I, InitialOffset + Symbols.skew()))
  80       return EC;
  81     InitialOffset += I.length();
  82   }
  83   return Error::success();
  84 }
  85
  86 Error CVSymbolVisitor::visitSymbolStreamFiltered(const CVSymbolArray &Symbols,
  87                                                  const FilterOptions &Filter) {
  88   if (!Filter.SymbolOffset)
  89     return visitSymbolStream(Symbols);
  90   uint32_t SymbolOffset = *Filter.SymbolOffset;
  91   uint32_t ParentRecurseDepth = Filter.ParentRecursiveDepth.value_or(0);
  92   uint32_t ChildrenRecurseDepth = Filter.ChildRecursiveDepth.value_or(0);
  93   if (!Symbols.isOffsetValid(SymbolOffset))
  94     return createStringError(inconvertibleErrorCode(), "Invalid symbol offset");
  95   CVSymbol Sym = *Symbols.at(SymbolOffset);
  96   uint32_t SymEndOffset =
  97       symbolOpensScope(Sym.kind()) ? getScopeEndOffset(Sym) : 0;
  98
  99   std::vector<uint32_t> ParentOffsets;
 100   std::vector<uint32_t> ParentEndOffsets;
 101   uint32_t ChildrenDepth = 0;
 102   for (auto Begin = Symbols.begin(), End = Symbols.end(); Begin != End;
 103        ++Begin) {
 104     uint32_t BeginOffset = Begin.offset();
 105     CVSymbol BeginSym = *Begin;
 106     if (BeginOffset < SymbolOffset) {
 107       if (symbolOpensScope(Begin->kind())) {
 108         uint32_t EndOffset = getScopeEndOffset(BeginSym);
 109         if (SymbolOffset < EndOffset) {
 110           ParentOffsets.push_back(BeginOffset);
 111           ParentEndOffsets.push_back(EndOffset);
 112         }
 113       }
 114     } else if (BeginOffset == SymbolOffset) {
 115       // Found symbol at offset. Visit its parent up to ParentRecurseDepth.
 116       if (ParentRecurseDepth >= ParentOffsets.size())
 117         ParentRecurseDepth = ParentOffsets.size();
 118       uint32_t StartIndex = ParentOffsets.size() - ParentRecurseDepth;
 119       while (StartIndex < ParentOffsets.size()) {
 120         if (!Symbols.isOffsetValid(ParentOffsets[StartIndex]))
 121           break;
 122         CVSymbol Parent = *Symbols.at(ParentOffsets[StartIndex]);
 123         if (auto EC = visitSymbolRecord(Parent, ParentOffsets[StartIndex]))
 124           return EC;
 125         ++StartIndex;
 126       }
 127       if (auto EC = visitSymbolRecord(Sym, SymbolOffset))
 128         return EC;
 129     } else if (BeginOffset <= SymEndOffset) {
 130       if (ChildrenRecurseDepth) {
 131         // Visit children.
 132         if (symbolEndsScope(Begin->kind()))
 133           --ChildrenDepth;
 134         if (ChildrenDepth < ChildrenRecurseDepth ||
 135             BeginOffset == SymEndOffset) {
 136           if (auto EC = visitSymbolRecord(BeginSym, BeginOffset))
 137             return EC;
 138         }
 139         if (symbolOpensScope(Begin->kind()))
 140           ++ChildrenDepth;
 141       }
 142     } else {
 143       // Visit parents' ends.
 144       if (ParentRecurseDepth && BeginOffset == ParentEndOffsets.back()) {
 145         if (auto EC = visitSymbolRecord(BeginSym, BeginOffset))
 146           return EC;
 147         ParentEndOffsets.pop_back();
 148         --ParentRecurseDepth;
 149       }
 150     }
 151   }
 152   return Error::success();
 153 }