1 //===- DWARFDebugPubTable.cpp ---------------------------------------------===//
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/DWARF/DWARFDebugPubTable.h"
10 #include "llvm/DebugInfo/DWARF/DWARFDataExtractor.h"
11 #include "llvm/ADT/StringRef.h"
12 #include "llvm/BinaryFormat/Dwarf.h"
13 #include "llvm/Support/DataExtractor.h"
14 #include "llvm/Support/Errc.h"
15 #include "llvm/Support/Format.h"
16 #include "llvm/Support/raw_ostream.h"
17 #include <cstdint>
18 
19 using namespace llvm;
20 using namespace dwarf;
21 
22 void DWARFDebugPubTable::extract(
23     DWARFDataExtractor Data, bool GnuStyle,
24     function_ref<void(Error)> RecoverableErrorHandler) {
25   this->GnuStyle = GnuStyle;
26   Sets.clear();
27   uint64_t Offset = 0;
28   while (Data.isValidOffset(Offset)) {
29     uint64_t SetOffset = Offset;
30     Sets.push_back({});
31     Set &NewSet = Sets.back();
32 
33     DataExtractor::Cursor C(Offset);
34     std::tie(NewSet.Length, NewSet.Format) = Data.getInitialLength(C);
35     if (!C) {
36       // Drop the newly added set because it does not contain anything useful
37       // to dump.
38       Sets.pop_back();
39       RecoverableErrorHandler(createStringError(
40           errc::invalid_argument,
41           "name lookup table at offset 0x%" PRIx64 " parsing failed: %s",
42           SetOffset, toString(C.takeError()).c_str()));
43       return;
44     }
45 
46     Offset = C.tell() + NewSet.Length;
47     DWARFDataExtractor SetData(Data, Offset);
48     const unsigned OffsetSize = dwarf::getDwarfOffsetByteSize(NewSet.Format);
49 
50     NewSet.Version = SetData.getU16(C);
51     NewSet.Offset = SetData.getRelocatedValue(C, OffsetSize);
52     NewSet.Size = SetData.getUnsigned(C, OffsetSize);
53 
54     if (!C) {
55       // Preserve the newly added set because at least some fields of the header
56       // are read and can be dumped.
57       RecoverableErrorHandler(
58           createStringError(errc::invalid_argument,
59                             "name lookup table at offset 0x%" PRIx64
60                             " does not have a complete header: %s",
61                             SetOffset, toString(C.takeError()).c_str()));
62       continue;
63     }
64 
65     while (C) {
66       uint64_t DieRef = SetData.getUnsigned(C, OffsetSize);
67       if (DieRef == 0)
68         break;
69       uint8_t IndexEntryValue = GnuStyle ? SetData.getU8(C) : 0;
70       StringRef Name = SetData.getCStrRef(C);
71       if (C)
72         NewSet.Entries.push_back(
73             {DieRef, PubIndexEntryDescriptor(IndexEntryValue), Name});
74     }
75 
76     if (!C) {
77       RecoverableErrorHandler(createStringError(
78           errc::invalid_argument,
79           "name lookup table at offset 0x%" PRIx64 " parsing failed: %s",
80           SetOffset, toString(C.takeError()).c_str()));
81       continue;
82     }
83     if (C.tell() != Offset)
84       RecoverableErrorHandler(createStringError(
85           errc::invalid_argument,
86           "name lookup table at offset 0x%" PRIx64
87           " has a terminator at offset 0x%" PRIx64
88           " before the expected end at 0x%" PRIx64,
89           SetOffset, C.tell() - OffsetSize, Offset - OffsetSize));
90   }
91 }
92 
93 void DWARFDebugPubTable::dump(raw_ostream &OS) const {
94   for (const Set &S : Sets) {
95     int OffsetDumpWidth = 2 * dwarf::getDwarfOffsetByteSize(S.Format);
96     OS << "length = " << format("0x%0*" PRIx64, OffsetDumpWidth, S.Length);
97     OS << ", format = " << dwarf::FormatString(S.Format);
98     OS << ", version = " << format("0x%04x", S.Version);
99     OS << ", unit_offset = "
100        << format("0x%0*" PRIx64, OffsetDumpWidth, S.Offset);
101     OS << ", unit_size = " << format("0x%0*" PRIx64, OffsetDumpWidth, S.Size)
102        << '\n';
103     OS << (GnuStyle ? "Offset     Linkage  Kind     Name\n"
104                     : "Offset     Name\n");
105 
106     for (const Entry &E : S.Entries) {
107       OS << format("0x%0*" PRIx64 " ", OffsetDumpWidth, E.SecOffset);
108       if (GnuStyle) {
109         StringRef EntryLinkage =
110             GDBIndexEntryLinkageString(E.Descriptor.Linkage);
111         StringRef EntryKind = dwarf::GDBIndexEntryKindString(E.Descriptor.Kind);
112         OS << format("%-8s", EntryLinkage.data()) << ' '
113            << format("%-8s", EntryKind.data()) << ' ';
114       }
115       OS << '\"' << E.Name << "\"\n";
116     }
117   }
118 }
119