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/SymbolRecord.h"
  13 #include "llvm/DebugInfo/CodeView/SymbolRecordHelpers.h"
  14 #include "llvm/DebugInfo/CodeView/SymbolVisitorCallbacks.h"
  15 #include "llvm/Support/BinaryStreamArray.h"
  16 #include "llvm/Support/ErrorHandling.h"
  17
  18 using namespace llvm;
  19 using namespace llvm::codeview;
  20
  21 CVSymbolVisitor::CVSymbolVisitor(SymbolVisitorCallbacks &Callbacks)
  22     : Callbacks(Callbacks) {}
  23
  24 template <typename T>
  25 static Error visitKnownRecord(CVSymbol &Record,
  26                               SymbolVisitorCallbacks &Callbacks) {
  27   SymbolRecordKind RK = static_cast<SymbolRecordKind>(Record.kind());
  28   T KnownRecord(RK);
  29   if (auto EC = Callbacks.visitKnownRecord(Record, KnownRecord))
  30     return EC;
  31   return Error::success();
  32 }
  33
  34 static Error finishVisitation(CVSymbol &Record,
  35                               SymbolVisitorCallbacks &Callbacks) {
  36   switch (Record.kind()) {
  37   default:
  38     if (auto EC = Callbacks.visitUnknownSymbol(Record))
  39       return EC;
  40     break;
  41 #define SYMBOL_RECORD(EnumName, EnumVal, Name)                                 \
  42   case EnumName: {                                                             \
  43     if (auto EC = visitKnownRecord<Name>(Record, Callbacks))                   \
  44       return EC;                                                               \
  45     break;                                                                     \
  46   }
  47 #define SYMBOL_RECORD_ALIAS(EnumName, EnumVal, Name, AliasName)                \
  48   SYMBOL_RECORD(EnumVal, EnumVal, AliasName)
  49 #include "llvm/DebugInfo/CodeView/CodeViewSymbols.def"
  50   }
  51
  52   if (auto EC = Callbacks.visitSymbolEnd(Record))
  53     return EC;
  54
  55   return Error::success();
  56 }
  57
  58 Error CVSymbolVisitor::visitSymbolRecord(CVSymbol &Record) {
  59   if (auto EC = Callbacks.visitSymbolBegin(Record))
  60     return EC;
  61   return finishVisitation(Record, Callbacks);
  62 }
  63
  64 Error CVSymbolVisitor::visitSymbolRecord(CVSymbol &Record, uint32_t Offset) {
  65   if (auto EC = Callbacks.visitSymbolBegin(Record, Offset))
  66     return EC;
  67   return finishVisitation(Record, Callbacks);
  68 }
  69
  70 Error CVSymbolVisitor::visitSymbolStream(const CVSymbolArray &Symbols) {
  71   for (auto I : Symbols) {
  72     if (auto EC = visitSymbolRecord(I))
  73       return EC;
  74   }
  75   return Error::success();
  76 }
  77
  78 Error CVSymbolVisitor::visitSymbolStream(const CVSymbolArray &Symbols,
  79                                          uint32_t InitialOffset) {
  80   for (auto I : Symbols) {
  81     if (auto EC = visitSymbolRecord(I, InitialOffset + Symbols.skew()))
  82       return EC;
  83     InitialOffset += I.length();
  84   }
  85   return Error::success();
  86 }
  87
  88 Error CVSymbolVisitor::visitSymbolStreamFiltered(const CVSymbolArray &Symbols,
  89                                                  const FilterOptions &Filter) {
  90   if (!Filter.SymbolOffset)
  91     return visitSymbolStream(Symbols);
  92   uint32_t SymbolOffset = *Filter.SymbolOffset;
  93   uint32_t ParentRecurseDepth = Filter.ParentRecursiveDepth.value_or(0);
  94   uint32_t ChildrenRecurseDepth = Filter.ChildRecursiveDepth.value_or(0);
  95   if (!Symbols.isOffsetValid(SymbolOffset))
  96     return createStringError(inconvertibleErrorCode(), "Invalid symbol offset");
  97   CVSymbol Sym = *Symbols.at(SymbolOffset);
  98   uint32_t SymEndOffset =
  99       symbolOpensScope(Sym.kind()) ? getScopeEndOffset(Sym) : 0;
 100
 101   std::vector<uint32_t> ParentOffsets;
 102   std::vector<uint32_t> ParentEndOffsets;
 103   uint32_t ChildrenDepth = 0;
 104   for (auto Begin = Symbols.begin(), End = Symbols.end(); Begin != End;
 105        ++Begin) {
 106     uint32_t BeginOffset = Begin.offset();
 107     CVSymbol BeginSym = *Begin;
 108     if (BeginOffset < SymbolOffset) {
 109       if (symbolOpensScope(Begin->kind())) {
 110         uint32_t EndOffset = getScopeEndOffset(BeginSym);
 111         if (SymbolOffset < EndOffset) {
 112           ParentOffsets.push_back(BeginOffset);
 113           ParentEndOffsets.push_back(EndOffset);
 114         }
 115       }
 116     } else if (BeginOffset == SymbolOffset) {
 117       // Found symbol at offset. Visit its parent up to ParentRecurseDepth.
 118       if (ParentRecurseDepth >= ParentOffsets.size())
 119         ParentRecurseDepth = ParentOffsets.size();
 120       uint32_t StartIndex = ParentOffsets.size() - ParentRecurseDepth;
 121       while (StartIndex < ParentOffsets.size()) {
 122         if (!Symbols.isOffsetValid(ParentOffsets[StartIndex]))
 123           break;
 124         CVSymbol Parent = *Symbols.at(ParentOffsets[StartIndex]);
 125         if (auto EC = visitSymbolRecord(Parent, ParentOffsets[StartIndex]))
 126           return EC;
 127         ++StartIndex;
 128       }
 129       if (auto EC = visitSymbolRecord(Sym, SymbolOffset))
 130         return EC;
 131     } else if (BeginOffset <= SymEndOffset) {
 132       if (ChildrenRecurseDepth) {
 133         // Visit children.
 134         if (symbolEndsScope(Begin->kind()))
 135           --ChildrenDepth;
 136         if (ChildrenDepth < ChildrenRecurseDepth ||
 137             BeginOffset == SymEndOffset) {
 138           if (auto EC = visitSymbolRecord(BeginSym, BeginOffset))
 139             return EC;
 140         }
 141         if (symbolOpensScope(Begin->kind()))
 142           ++ChildrenDepth;
 143       }
 144     } else {
 145       // Visit parents' ends.
 146       if (ParentRecurseDepth && BeginOffset == ParentEndOffsets.back()) {
 147         if (auto EC = visitSymbolRecord(BeginSym, BeginOffset))
 148           return EC;
 149         ParentEndOffsets.pop_back();
 150         --ParentRecurseDepth;
 151       }
 152     }
 153   }
 154   return Error::success();
 155 }