summaryrefslogtreecommitdiffstats
path: root/llvm/lib/DebugInfo/DWARF/DWARFDebugRnglists.cpp
blob: b19c808a8fb37a9fdde106d77f048eb3357497fa (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
//===- DWARFDebugRnglists.cpp ---------------------------------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

#include "llvm/DebugInfo/DWARF/DWARFDebugRnglists.h"
#include "llvm/BinaryFormat/Dwarf.h"
#include "llvm/DebugInfo/DWARF/DWARFUnit.h"
#include "llvm/Support/Error.h"
#include "llvm/Support/Format.h"
#include "llvm/Support/raw_ostream.h"

using namespace llvm;

template <typename... Ts>
static Error createError(char const *Fmt, const Ts &... Vals) {
  std::string Buffer;
  raw_string_ostream Stream(Buffer);
  Stream << format(Fmt, Vals...);
  return make_error<StringError>(Stream.str(), inconvertibleErrorCode());
}

namespace llvm {   // workaround for gcc bug
template <>
Error DWARFListType<RangeListEntry>::createError(const char *Fmt, const char *s,
                                                 uint32_t Val) {
  return ::createError(Fmt, s, Val);
}
}

Error RangeListEntry::extract(DWARFDataExtractor Data, uint32_t End,
                              uint32_t *OffsetPtr) {
  Offset = *OffsetPtr;
  SectionIndex = -1ULL;
  // The caller should guarantee that we have at least 1 byte available, so
  // we just assert instead of revalidate.
  assert(*OffsetPtr < End &&
         "not enough space to extract a rangelist encoding");
  uint8_t Encoding = Data.getU8(OffsetPtr);

  switch (Encoding) {
  case dwarf::DW_RLE_end_of_list:
    Value0 = Value1 = 0;
    break;
  // TODO: Support other encodings.
  case dwarf::DW_RLE_base_addressx:
    return createError("unsupported rnglists encoding DW_RLE_base_addressx "
                       "at offset 0x%" PRIx32,
                       *OffsetPtr - 1);
  case dwarf::DW_RLE_startx_endx:
    return createError("unsupported rnglists encoding DW_RLE_startx_endx at "
                       "offset 0x%" PRIx32,
                       *OffsetPtr - 1);
  case dwarf::DW_RLE_startx_length:
    return createError("unsupported rnglists encoding DW_RLE_startx_length "
                       "at offset 0x%" PRIx32,
                       *OffsetPtr - 1);
  case dwarf::DW_RLE_offset_pair: {
    uint32_t PreviousOffset = *OffsetPtr - 1;
    Value0 = Data.getULEB128(OffsetPtr);
    Value1 = Data.getULEB128(OffsetPtr);
    if (End < *OffsetPtr)
      return createError("read past end of table when reading "
                         "DW_RLE_offset_pair encoding at offset 0x%" PRIx32,
                         PreviousOffset);
    break;
  }
  case dwarf::DW_RLE_base_address: {
    if ((End - *OffsetPtr) < Data.getAddressSize())
      return createError("insufficient space remaining in table for "
                         "DW_RLE_base_address encoding at offset 0x%" PRIx32,
                         *OffsetPtr - 1);
    Value0 = Data.getRelocatedAddress(OffsetPtr, &SectionIndex);
    break;
  }
  case dwarf::DW_RLE_start_end: {
    if ((End - *OffsetPtr) < unsigned(Data.getAddressSize() * 2))
      return createError("insufficient space remaining in table for "
                         "DW_RLE_start_end encoding "
                         "at offset 0x%" PRIx32,
                         *OffsetPtr - 1);
    Value0 = Data.getRelocatedAddress(OffsetPtr, &SectionIndex);
    Value1 = Data.getRelocatedAddress(OffsetPtr);
    break;
  }
  case dwarf::DW_RLE_start_length: {
    uint32_t PreviousOffset = *OffsetPtr - 1;
    Value0 = Data.getRelocatedAddress(OffsetPtr, &SectionIndex);
    Value1 = Data.getULEB128(OffsetPtr);
    if (End < *OffsetPtr)
      return createError("read past end of table when reading "
                         "DW_RLE_start_length encoding at offset 0x%" PRIx32,
                         PreviousOffset);
    break;
  }
  default:
    return createError("unknown rnglists encoding 0x%" PRIx32
                       " at offset 0x%" PRIx32,
                       uint32_t(Encoding), *OffsetPtr - 1);
  }

  EntryKind = Encoding;
  return Error::success();
}

DWARFAddressRangesVector DWARFDebugRnglist::getAbsoluteRanges(
    llvm::Optional<BaseAddress> BaseAddr) const {
  DWARFAddressRangesVector Res;
  for (const RangeListEntry &RLE : Entries) {
    if (RLE.EntryKind == dwarf::DW_RLE_end_of_list)
      break;
    if (RLE.EntryKind == dwarf::DW_RLE_base_address) {
      BaseAddr = {RLE.Value0, RLE.SectionIndex};
      continue;
    }

    DWARFAddressRange E;
    E.SectionIndex = RLE.SectionIndex;
    if (BaseAddr && E.SectionIndex == -1ULL)
      E.SectionIndex = BaseAddr->SectionIndex;

    switch (RLE.EntryKind) {
    case dwarf::DW_RLE_offset_pair:
      E.LowPC = RLE.Value0;
      E.HighPC = RLE.Value1;
      if (BaseAddr) {
        E.LowPC += BaseAddr->Address;
        E.HighPC += BaseAddr->Address;
      }
      break;
    case dwarf::DW_RLE_start_end:
      E.LowPC = RLE.Value0;
      E.HighPC = RLE.Value1;
      break;
    case dwarf::DW_RLE_start_length:
      E.LowPC = RLE.Value0;
      E.HighPC = E.LowPC + RLE.Value1;
      break;
    default:
      // Unsupported encodings should have been reported during extraction,
      // so we should not run into any here.
      llvm_unreachable("Unsupported range list encoding");
    }
    Res.push_back(E);
  }
  return Res;
}

void RangeListEntry::dump(raw_ostream &OS, uint8_t AddrSize,
                          uint8_t MaxEncodingStringLength,
                          uint64_t &CurrentBase, DIDumpOptions DumpOpts) const {
  auto PrintRawEntry = [](raw_ostream &OS, const RangeListEntry &Entry,
                          uint8_t AddrSize, DIDumpOptions DumpOpts) {
    if (DumpOpts.Verbose) {
      DumpOpts.DisplayRawContents = true;
      DWARFAddressRange(Entry.Value0, Entry.Value1)
          .dump(OS, AddrSize, DumpOpts);
      OS << " => ";
    }
  };

  if (DumpOpts.Verbose) {
    // Print the section offset in verbose mode.
    OS << format("0x%8.8" PRIx32 ":", Offset);
    auto EncodingString = dwarf::RangeListEncodingString(EntryKind);
    // Unsupported encodings should have been reported during parsing.
    assert(!EncodingString.empty() && "Unknown range entry encoding");
    OS << format(" [%s%*c", EncodingString.data(),
                 MaxEncodingStringLength - EncodingString.size() + 1, ']');
    if (EntryKind != dwarf::DW_RLE_end_of_list)
      OS << ": ";
  }

  switch (EntryKind) {
  case dwarf::DW_RLE_end_of_list:
    OS << (DumpOpts.Verbose ? "" : "<End of list>");
    break;
  case dwarf::DW_RLE_base_address:
    // In non-verbose mode we do not print anything for this entry.
    CurrentBase = Value0;
    if (!DumpOpts.Verbose)
      return;
    OS << format(" 0x%*.*" PRIx64, AddrSize * 2, AddrSize * 2, Value0);
    break;
  case dwarf::DW_RLE_start_length:
    PrintRawEntry(OS, *this, AddrSize, DumpOpts);
    DWARFAddressRange(Value0, Value0 + Value1).dump(OS, AddrSize, DumpOpts);
    break;
  case dwarf::DW_RLE_offset_pair:
    PrintRawEntry(OS, *this, AddrSize, DumpOpts);
    DWARFAddressRange(Value0 + CurrentBase, Value1 + CurrentBase)
        .dump(OS, AddrSize, DumpOpts);
    break;
  case dwarf::DW_RLE_start_end:
    DWARFAddressRange(Value0, Value1).dump(OS, AddrSize, DumpOpts);
    break;
  default:
    llvm_unreachable("Unsupported range list encoding");
  }
  OS << "\n";
}
OpenPOWER on IntegriCloud