1 //===--- DWARFVisitor.cpp ---------------------------------------*- C++ -*-===//
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 //===----------------------------------------------------------------------===//
11 
12 #include "DWARFVisitor.h"
13 #include "llvm/ObjectYAML/DWARFYAML.h"
14 
15 using namespace llvm;
16 
17 template <typename T>
18 void DWARFYAML::VisitorImpl<T>::onVariableSizeValue(uint64_t U, unsigned Size) {
19   switch (Size) {
20   case 8:
21     onValue((uint64_t)U);
22     break;
23   case 4:
24     onValue((uint32_t)U);
25     break;
26   case 2:
27     onValue((uint16_t)U);
28     break;
29   case 1:
30     onValue((uint8_t)U);
31     break;
32   default:
33     llvm_unreachable("Invalid integer write size.");
34   }
35 }
36 
37 static unsigned getOffsetSize(const DWARFYAML::Unit &Unit) {
38   return Unit.Length.isDWARF64() ? 8 : 4;
39 }
40 
41 static unsigned getRefSize(const DWARFYAML::Unit &Unit) {
42   if (Unit.Version == 2)
43     return Unit.AddrSize;
44   return getOffsetSize(Unit);
45 }
46 
47 template <typename T> void DWARFYAML::VisitorImpl<T>::traverseDebugInfo() {
48   for (auto &Unit : DebugInfo.CompileUnits) {
49     onStartCompileUnit(Unit);
50     auto FirstAbbrevCode = Unit.Entries[0].AbbrCode;
51 
52     for (auto &Entry : Unit.Entries) {
53       onStartDIE(Unit, Entry);
54       if (Entry.AbbrCode == 0u)
55         continue;
56       auto &Abbrev = DebugInfo.AbbrevDecls[Entry.AbbrCode - FirstAbbrevCode];
57       auto FormVal = Entry.Values.begin();
58       auto AbbrForm = Abbrev.Attributes.begin();
59       for (;
60            FormVal != Entry.Values.end() && AbbrForm != Abbrev.Attributes.end();
61            ++FormVal, ++AbbrForm) {
62         onForm(*AbbrForm, *FormVal);
63         dwarf::Form Form = AbbrForm->Form;
64         bool Indirect;
65         do {
66           Indirect = false;
67           switch (Form) {
68           case dwarf::DW_FORM_addr:
69             onVariableSizeValue(FormVal->Value, Unit.AddrSize);
70             break;
71           case dwarf::DW_FORM_ref_addr:
72             onVariableSizeValue(FormVal->Value, getRefSize(Unit));
73             break;
74           case dwarf::DW_FORM_exprloc:
75           case dwarf::DW_FORM_block:
76             onValue((uint64_t)FormVal->BlockData.size(), true);
77             onValue(
78                 MemoryBufferRef(StringRef((const char *)&FormVal->BlockData[0],
79                                           FormVal->BlockData.size()),
80                                 ""));
81             break;
82           case dwarf::DW_FORM_block1: {
83             auto writeSize = FormVal->BlockData.size();
84             onValue((uint8_t)writeSize);
85             onValue(
86                 MemoryBufferRef(StringRef((const char *)&FormVal->BlockData[0],
87                                           FormVal->BlockData.size()),
88                                 ""));
89             break;
90           }
91           case dwarf::DW_FORM_block2: {
92             auto writeSize = FormVal->BlockData.size();
93             onValue((uint16_t)writeSize);
94             onValue(
95                 MemoryBufferRef(StringRef((const char *)&FormVal->BlockData[0],
96                                           FormVal->BlockData.size()),
97                                 ""));
98             break;
99           }
100           case dwarf::DW_FORM_block4: {
101             auto writeSize = FormVal->BlockData.size();
102             onValue((uint32_t)writeSize);
103             onValue(
104                 MemoryBufferRef(StringRef((const char *)&FormVal->BlockData[0],
105                                           FormVal->BlockData.size()),
106                                 ""));
107             break;
108           }
109           case dwarf::DW_FORM_data1:
110           case dwarf::DW_FORM_ref1:
111           case dwarf::DW_FORM_flag:
112           case dwarf::DW_FORM_strx1:
113           case dwarf::DW_FORM_addrx1:
114             onValue((uint8_t)FormVal->Value);
115             break;
116           case dwarf::DW_FORM_data2:
117           case dwarf::DW_FORM_ref2:
118           case dwarf::DW_FORM_strx2:
119           case dwarf::DW_FORM_addrx2:
120             onValue((uint16_t)FormVal->Value);
121             break;
122           case dwarf::DW_FORM_data4:
123           case dwarf::DW_FORM_ref4:
124           case dwarf::DW_FORM_ref_sup4:
125           case dwarf::DW_FORM_strx4:
126           case dwarf::DW_FORM_addrx4:
127             onValue((uint32_t)FormVal->Value);
128             break;
129           case dwarf::DW_FORM_data8:
130           case dwarf::DW_FORM_ref8:
131           case dwarf::DW_FORM_ref_sup8:
132             onValue((uint64_t)FormVal->Value);
133             break;
134           case dwarf::DW_FORM_sdata:
135             onValue((int64_t)FormVal->Value, true);
136             break;
137           case dwarf::DW_FORM_udata:
138           case dwarf::DW_FORM_ref_udata:
139             onValue((uint64_t)FormVal->Value, true);
140             break;
141           case dwarf::DW_FORM_string:
142             onValue(FormVal->CStr);
143             break;
144           case dwarf::DW_FORM_indirect:
145             onValue((uint64_t)FormVal->Value, true);
146             Indirect = true;
147             Form = static_cast<dwarf::Form>((uint64_t)FormVal->Value);
148             ++FormVal;
149             break;
150           case dwarf::DW_FORM_strp:
151           case dwarf::DW_FORM_sec_offset:
152           case dwarf::DW_FORM_GNU_ref_alt:
153           case dwarf::DW_FORM_GNU_strp_alt:
154           case dwarf::DW_FORM_line_strp:
155           case dwarf::DW_FORM_strp_sup:
156             onVariableSizeValue(FormVal->Value, getOffsetSize(Unit));
157             break;
158           case dwarf::DW_FORM_ref_sig8:
159             onValue((uint64_t)FormVal->Value);
160             break;
161           case dwarf::DW_FORM_GNU_addr_index:
162           case dwarf::DW_FORM_GNU_str_index:
163             onValue((uint64_t)FormVal->Value, true);
164             break;
165           default:
166             break;
167           }
168         } while (Indirect);
169       }
170       onEndDIE(Unit, Entry);
171     }
172     onEndCompileUnit(Unit);
173   }
174 }
175 
176 // Explicitly instantiate the two template expansions.
177 template class DWARFYAML::VisitorImpl<DWARFYAML::Data>;
178 template class DWARFYAML::VisitorImpl<const DWARFYAML::Data>;
179