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
CVSymbolVisitor(SymbolVisitorCallbacks & Callbacks)21 CVSymbolVisitor::CVSymbolVisitor(SymbolVisitorCallbacks &Callbacks)
22 : Callbacks(Callbacks) {}
23
24 template <typename T>
visitKnownRecord(CVSymbol & Record,SymbolVisitorCallbacks & Callbacks)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
finishVisitation(CVSymbol & Record,SymbolVisitorCallbacks & Callbacks)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
visitSymbolRecord(CVSymbol & Record)58 Error CVSymbolVisitor::visitSymbolRecord(CVSymbol &Record) {
59 if (auto EC = Callbacks.visitSymbolBegin(Record))
60 return EC;
61 return finishVisitation(Record, Callbacks);
62 }
63
visitSymbolRecord(CVSymbol & Record,uint32_t Offset)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
visitSymbolStream(const CVSymbolArray & Symbols)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
visitSymbolStream(const CVSymbolArray & Symbols,uint32_t InitialOffset)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
visitSymbolStreamFiltered(const CVSymbolArray & Symbols,const FilterOptions & Filter)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 }
156