1 //===- DWARFDebugAbbrev.cpp -----------------------------------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9
10 #include "llvm/DebugInfo/DWARF/DWARFDebugAbbrev.h"
11 #include "llvm/Support/Format.h"
12 #include "llvm/Support/raw_ostream.h"
13 #include <algorithm>
14 #include <cinttypes>
15 #include <cstdint>
16
17 using namespace llvm;
18
DWARFAbbreviationDeclarationSet()19 DWARFAbbreviationDeclarationSet::DWARFAbbreviationDeclarationSet() {
20 clear();
21 }
22
clear()23 void DWARFAbbreviationDeclarationSet::clear() {
24 Offset = 0;
25 FirstAbbrCode = 0;
26 Decls.clear();
27 }
28
extract(DataExtractor Data,uint32_t * OffsetPtr)29 bool DWARFAbbreviationDeclarationSet::extract(DataExtractor Data,
30 uint32_t *OffsetPtr) {
31 clear();
32 const uint32_t BeginOffset = *OffsetPtr;
33 Offset = BeginOffset;
34 DWARFAbbreviationDeclaration AbbrDecl;
35 uint32_t PrevAbbrCode = 0;
36 while (AbbrDecl.extract(Data, OffsetPtr)) {
37 if (FirstAbbrCode == 0) {
38 FirstAbbrCode = AbbrDecl.getCode();
39 } else {
40 if (PrevAbbrCode + 1 != AbbrDecl.getCode()) {
41 // Codes are not consecutive, can't do O(1) lookups.
42 FirstAbbrCode = UINT32_MAX;
43 }
44 }
45 PrevAbbrCode = AbbrDecl.getCode();
46 Decls.push_back(std::move(AbbrDecl));
47 }
48 return BeginOffset != *OffsetPtr;
49 }
50
dump(raw_ostream & OS) const51 void DWARFAbbreviationDeclarationSet::dump(raw_ostream &OS) const {
52 for (const auto &Decl : Decls)
53 Decl.dump(OS);
54 }
55
56 const DWARFAbbreviationDeclaration *
getAbbreviationDeclaration(uint32_t AbbrCode) const57 DWARFAbbreviationDeclarationSet::getAbbreviationDeclaration(
58 uint32_t AbbrCode) const {
59 if (FirstAbbrCode == UINT32_MAX) {
60 for (const auto &Decl : Decls) {
61 if (Decl.getCode() == AbbrCode)
62 return &Decl;
63 }
64 return nullptr;
65 }
66 if (AbbrCode < FirstAbbrCode || AbbrCode >= FirstAbbrCode + Decls.size())
67 return nullptr;
68 return &Decls[AbbrCode - FirstAbbrCode];
69 }
70
DWARFDebugAbbrev()71 DWARFDebugAbbrev::DWARFDebugAbbrev() { clear(); }
72
clear()73 void DWARFDebugAbbrev::clear() {
74 AbbrDeclSets.clear();
75 PrevAbbrOffsetPos = AbbrDeclSets.end();
76 }
77
extract(DataExtractor Data)78 void DWARFDebugAbbrev::extract(DataExtractor Data) {
79 clear();
80 this->Data = Data;
81 }
82
parse() const83 void DWARFDebugAbbrev::parse() const {
84 if (!Data)
85 return;
86 uint32_t Offset = 0;
87 DWARFAbbreviationDeclarationSet AbbrDecls;
88 auto I = AbbrDeclSets.begin();
89 while (Data->isValidOffset(Offset)) {
90 while (I != AbbrDeclSets.end() && I->first < Offset)
91 ++I;
92 uint32_t CUAbbrOffset = Offset;
93 if (!AbbrDecls.extract(*Data, &Offset))
94 break;
95 AbbrDeclSets.insert(I, std::make_pair(CUAbbrOffset, std::move(AbbrDecls)));
96 }
97 Data = None;
98 }
99
dump(raw_ostream & OS) const100 void DWARFDebugAbbrev::dump(raw_ostream &OS) const {
101 parse();
102
103 if (AbbrDeclSets.empty()) {
104 OS << "< EMPTY >\n";
105 return;
106 }
107
108 for (const auto &I : AbbrDeclSets) {
109 OS << format("Abbrev table for offset: 0x%8.8" PRIx64 "\n", I.first);
110 I.second.dump(OS);
111 }
112 }
113
114 const DWARFAbbreviationDeclarationSet*
getAbbreviationDeclarationSet(uint64_t CUAbbrOffset) const115 DWARFDebugAbbrev::getAbbreviationDeclarationSet(uint64_t CUAbbrOffset) const {
116 const auto End = AbbrDeclSets.end();
117 if (PrevAbbrOffsetPos != End && PrevAbbrOffsetPos->first == CUAbbrOffset) {
118 return &(PrevAbbrOffsetPos->second);
119 }
120
121 const auto Pos = AbbrDeclSets.find(CUAbbrOffset);
122 if (Pos != End) {
123 PrevAbbrOffsetPos = Pos;
124 return &(Pos->second);
125 }
126
127 if (Data && CUAbbrOffset < Data->getData().size()) {
128 uint32_t Offset = CUAbbrOffset;
129 DWARFAbbreviationDeclarationSet AbbrDecls;
130 if (!AbbrDecls.extract(*Data, &Offset))
131 return nullptr;
132 PrevAbbrOffsetPos =
133 AbbrDeclSets.insert(std::make_pair(CUAbbrOffset, std::move(AbbrDecls)))
134 .first;
135 return &PrevAbbrOffsetPos->second;
136 }
137
138 return nullptr;
139 }
140