LLVM  8.0.1
DWARFVisitor.cpp
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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>;
llvm::DWARFYAML::Abbrev::Attributes
std::vector< AttributeAbbrev > Attributes
Definition: DWARFYAML.h:58
llvm
This class represents lattice values for constants.
Definition: AllocatorList.h:24
getRefSize
static unsigned getRefSize(const DWARFYAML::Unit &Unit)
Definition: DWARFVisitor.cpp:41
llvm::DWARFYAML::Unit::Length
InitialLength Length
Definition: DWARFYAML.h:102
Unit
struct UnitT Unit
llvm::DWARFYAML::Unit::Entries
std::vector< Entry > Entries
Definition: DWARFYAML.h:107
llvm::DWARFYAML::Entry::Values
std::vector< FormValue > Values
Definition: DWARFYAML.h:98
llvm_unreachable
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
Definition: ErrorHandling.h:136
uint32_t
llvm::DWARFYAML::VisitorImpl
A class to visits DWARFYAML Compile Units and DIEs in preorder.
Definition: DWARFVisitor.h:33
llvm::DWARFYAML::Entry::AbbrCode
llvm::yaml::Hex32 AbbrCode
Definition: DWARFYAML.h:97
DWARFYAML.h
This file declares classes for handling the YAML representation of DWARF Debug Info.
Size
uint32_t Size
Definition: Profile.cpp:47
llvm::StringRef
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:49
getOffsetSize
static unsigned getOffsetSize(const DWARFYAML::Unit &Unit)
Definition: DWARFVisitor.cpp:37
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