1 //===- DWARFDebugMacro.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/DWARFDebugMacro.h"
10 #include "llvm/BinaryFormat/Dwarf.h"
11 #include "llvm/DebugInfo/DWARF/DWARFContext.h"
12 #include "llvm/DebugInfo/DWARF/DWARFDataExtractor.h"
13 #include "llvm/Support/WithColor.h"
14 #include "llvm/Support/raw_ostream.h"
15 #include <cstdint>
16 
17 using namespace llvm;
18 using namespace dwarf;
19 
20 DwarfFormat DWARFDebugMacro::MacroHeader::getDwarfFormat() const {
21   return Flags & MACRO_OFFSET_SIZE ? DWARF64 : DWARF32;
22 }
23 
24 uint8_t DWARFDebugMacro::MacroHeader::getOffsetByteSize() const {
25   return getDwarfOffsetByteSize(getDwarfFormat());
26 }
27 
28 void DWARFDebugMacro::MacroHeader::dumpMacroHeader(raw_ostream &OS) const {
29   // FIXME: Add support for dumping opcode_operands_table
30   OS << format("macro header: version = 0x%04" PRIx16, Version)
31      << format(", flags = 0x%02" PRIx8, Flags)
32      << ", format = " << FormatString(getDwarfFormat());
33   if (Flags & MACRO_DEBUG_LINE_OFFSET)
34     OS << format(", debug_line_offset = 0x%0*" PRIx64, 2 * getOffsetByteSize(),
35                  DebugLineOffset);
36   OS << "\n";
37 }
38 
39 void DWARFDebugMacro::dump(raw_ostream &OS) const {
40   unsigned IndLevel = 0;
41   for (const auto &Macros : MacroLists) {
42     OS << format("0x%08" PRIx64 ":\n", Macros.Offset);
43     if (Macros.Header.Version >= 5)
44       Macros.Header.dumpMacroHeader(OS);
45     for (const Entry &E : Macros.Macros) {
46       // There should not be DW_MACINFO_end_file when IndLevel is Zero. However,
47       // this check handles the case of corrupted ".debug_macinfo" section.
48       if (IndLevel > 0)
49         IndLevel -= (E.Type == DW_MACINFO_end_file);
50       // Print indentation.
51       for (unsigned I = 0; I < IndLevel; I++)
52         OS << "  ";
53       IndLevel += (E.Type == DW_MACINFO_start_file);
54       // Based on which version we are handling choose appropriate macro forms.
55       if (Macros.Header.Version >= 5)
56         WithColor(OS, HighlightColor::Macro).get() << MacroString(E.Type);
57       else
58         WithColor(OS, HighlightColor::Macro).get() << MacinfoString(E.Type);
59       switch (E.Type) {
60       default:
61         // Got a corrupted ".debug_macinfo/.debug_macro" section (invalid
62         // macinfo type).
63         break;
64         // debug_macro and debug_macinfo share some common encodings.
65         // DW_MACRO_define     == DW_MACINFO_define
66         // DW_MACRO_undef      == DW_MACINFO_undef
67         // DW_MACRO_start_file == DW_MACINFO_start_file
68         // DW_MACRO_end_file   == DW_MACINFO_end_file
69         // For readability/uniformity we are using DW_MACRO_*.
70       case DW_MACRO_define:
71       case DW_MACRO_undef:
72       case DW_MACRO_define_strp:
73       case DW_MACRO_undef_strp:
74       case DW_MACRO_define_strx:
75       case DW_MACRO_undef_strx:
76         OS << " - lineno: " << E.Line;
77         OS << " macro: " << E.MacroStr;
78         break;
79       case DW_MACRO_start_file:
80         OS << " - lineno: " << E.Line;
81         OS << " filenum: " << E.File;
82         break;
83       case DW_MACRO_import:
84         OS << format(" - import offset: 0x%0*" PRIx64,
85                      2 * Macros.Header.getOffsetByteSize(), E.ImportOffset);
86         break;
87       case DW_MACRO_end_file:
88         break;
89       case DW_MACINFO_vendor_ext:
90         OS << " - constant: " << E.ExtConstant;
91         OS << " string: " << E.ExtStr;
92         break;
93       }
94       OS << "\n";
95     }
96   }
97 }
98 
99 Error DWARFDebugMacro::parseImpl(
100     Optional<DWARFUnitVector::iterator_range> Units,
101     Optional<DataExtractor> StringExtractor, DWARFDataExtractor Data,
102     bool IsMacro) {
103   uint64_t Offset = 0;
104   MacroList *M = nullptr;
105   using MacroToUnitsMap = DenseMap<uint64_t, DWARFUnit *>;
106   MacroToUnitsMap MacroToUnits;
107   if (IsMacro && Data.isValidOffset(Offset)) {
108     // Keep a mapping from Macro contribution to CUs, this will
109     // be needed while retrieving macro from DW_MACRO_define_strx form.
110     for (const auto &U : Units.getValue())
111       if (auto CUDIE = U->getUnitDIE())
112         // Skip units which does not contibutes to macro section.
113         if (auto MacroOffset = toSectionOffset(CUDIE.find(DW_AT_macros)))
114           MacroToUnits.try_emplace(*MacroOffset, U.get());
115   }
116   while (Data.isValidOffset(Offset)) {
117     if (!M) {
118       MacroLists.emplace_back();
119       M = &MacroLists.back();
120       M->Offset = Offset;
121       if (IsMacro) {
122         auto Err = M->Header.parseMacroHeader(Data, &Offset);
123         if (Err)
124           return Err;
125       }
126     }
127     // A macro list entry consists of:
128     M->Macros.emplace_back();
129     Entry &E = M->Macros.back();
130     // 1. Macinfo type
131     E.Type = Data.getULEB128(&Offset);
132 
133     if (E.Type == 0) {
134       // Reached end of a ".debug_macinfo/debug_macro" section contribution.
135       M = nullptr;
136       continue;
137     }
138 
139     switch (E.Type) {
140     default:
141       // Got a corrupted ".debug_macinfo" section (invalid macinfo type).
142       // Push the corrupted entry to the list and halt parsing.
143       E.Type = DW_MACINFO_invalid;
144       return Error::success();
145     // debug_macro and debug_macinfo share some common encodings.
146     // DW_MACRO_define     == DW_MACINFO_define
147     // DW_MACRO_undef      == DW_MACINFO_undef
148     // DW_MACRO_start_file == DW_MACINFO_start_file
149     // DW_MACRO_end_file   == DW_MACINFO_end_file
150     // For readibility/uniformity we are using DW_MACRO_*.
151     case DW_MACRO_define:
152     case DW_MACRO_undef:
153       // 2. Source line
154       E.Line = Data.getULEB128(&Offset);
155       // 3. Macro string
156       E.MacroStr = Data.getCStr(&Offset);
157       break;
158     case DW_MACRO_define_strp:
159     case DW_MACRO_undef_strp: {
160       if (!IsMacro) {
161         // DW_MACRO_define_strp is a new form introduced in DWARFv5, it is
162         // not supported in debug_macinfo[.dwo] sections. Assume it as an
163         // invalid entry, push it and halt parsing.
164         E.Type = DW_MACINFO_invalid;
165         return Error::success();
166       }
167       uint64_t StrOffset = 0;
168       // 2. Source line
169       E.Line = Data.getULEB128(&Offset);
170       // 3. Macro string
171       StrOffset =
172           Data.getRelocatedValue(M->Header.getOffsetByteSize(), &Offset);
173       assert(StringExtractor && "String Extractor not found");
174       E.MacroStr = StringExtractor->getCStr(&StrOffset);
175       break;
176     }
177     case DW_MACRO_define_strx:
178     case DW_MACRO_undef_strx: {
179       if (!IsMacro) {
180         // DW_MACRO_define_strx is a new form introduced in DWARFv5, it is
181         // not supported in debug_macinfo[.dwo] sections. Assume it as an
182         // invalid entry, push it and halt parsing.
183         E.Type = DW_MACINFO_invalid;
184         return Error::success();
185       }
186       E.Line = Data.getULEB128(&Offset);
187       auto MacroContributionOffset = MacroToUnits.find(M->Offset);
188       if (MacroContributionOffset == MacroToUnits.end())
189         return createStringError(errc::invalid_argument,
190                                  "Macro contribution of the unit not found");
191       Optional<uint64_t> StrOffset =
192           MacroContributionOffset->second->getStringOffsetSectionItem(
193               Data.getULEB128(&Offset));
194       if (!StrOffset)
195         return createStringError(
196             errc::invalid_argument,
197             "String offsets contribution of the unit not found");
198       E.MacroStr =
199           MacroContributionOffset->second->getStringExtractor().getCStr(
200               &*StrOffset);
201       break;
202     }
203     case DW_MACRO_start_file:
204       // 2. Source line
205       E.Line = Data.getULEB128(&Offset);
206       // 3. Source file id
207       E.File = Data.getULEB128(&Offset);
208       break;
209     case DW_MACRO_end_file:
210       break;
211     case DW_MACRO_import:
212       E.ImportOffset =
213           Data.getRelocatedValue(M->Header.getOffsetByteSize(), &Offset);
214       break;
215     case DW_MACINFO_vendor_ext:
216       // 2. Vendor extension constant
217       E.ExtConstant = Data.getULEB128(&Offset);
218       // 3. Vendor extension string
219       E.ExtStr = Data.getCStr(&Offset);
220       break;
221     }
222   }
223   return Error::success();
224 }
225 
226 Error DWARFDebugMacro::MacroHeader::parseMacroHeader(DWARFDataExtractor Data,
227                                                      uint64_t *Offset) {
228   Version = Data.getU16(Offset);
229   uint8_t FlagData = Data.getU8(Offset);
230 
231   // FIXME: Add support for parsing opcode_operands_table
232   if (FlagData & MACRO_OPCODE_OPERANDS_TABLE)
233     return createStringError(errc::not_supported,
234                              "opcode_operands_table is not supported");
235   Flags = FlagData;
236   if (Flags & MACRO_DEBUG_LINE_OFFSET)
237     DebugLineOffset = Data.getUnsigned(Offset, getOffsetByteSize());
238   return Error::success();
239 }
240