1 //===-- DWARFCompileUnit.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 "DWARFCompileUnit.h"
10 #include "DWARFDebugAranges.h"
11 #include "SymbolFileDWARFDebugMap.h"
12 
13 #include "lldb/Symbol/CompileUnit.h"
14 #include "lldb/Symbol/LineTable.h"
15 #include "lldb/Utility/Stream.h"
16 
17 using namespace lldb;
18 using namespace lldb_private;
19 
20 void DWARFCompileUnit::Dump(Stream *s) const {
21   s->Format(
22 
23       "{0:x16}: Compile Unit: length = {1:x8}, version = {2:x}, "
24       "abbr_offset = {3:x8}, addr_size = {4:x2} (next CU at "
25       "[{5:x16}])\n",
26       GetOffset(), GetLength(), GetVersion(), (uint32_t)GetAbbrevOffset(),
27       GetAddressByteSize(), GetNextUnitOffset());
28 }
29 
30 void DWARFCompileUnit::BuildAddressRangeTable(
31     DWARFDebugAranges *debug_aranges) {
32   // This function is usually called if there in no .debug_aranges section in
33   // order to produce a compile unit level set of address ranges that is
34   // accurate.
35 
36   size_t num_debug_aranges = debug_aranges->GetNumRanges();
37 
38   // First get the compile unit DIE only and check contains ranges information.
39   const DWARFDebugInfoEntry *die = GetUnitDIEPtrOnly();
40 
41   const dw_offset_t cu_offset = GetOffset();
42   if (die) {
43     DWARFRangeList ranges;
44     const size_t num_ranges =
45         die->GetAttributeAddressRanges(this, ranges, /*check_hi_lo_pc=*/true);
46     if (num_ranges > 0) {
47       for (size_t i = 0; i < num_ranges; ++i) {
48         const DWARFRangeList::Entry &range = ranges.GetEntryRef(i);
49         debug_aranges->AppendRange(cu_offset, range.GetRangeBase(),
50                                    range.GetRangeEnd());
51       }
52 
53       return;
54     }
55   }
56 
57   if (debug_aranges->GetNumRanges() == num_debug_aranges) {
58     // We got nothing from the debug info, try to build the arange table from
59     // the debug map OSO aranges.
60     SymbolContext sc;
61     sc.comp_unit = m_dwarf.GetCompUnitForDWARFCompUnit(*this);
62     if (sc.comp_unit) {
63       SymbolFileDWARFDebugMap *debug_map_sym_file =
64           m_dwarf.GetDebugMapSymfile();
65       if (debug_map_sym_file) {
66         auto *cu_info =
67             debug_map_sym_file->GetCompileUnitInfo(&GetSymbolFileDWARF());
68         // If there are extra compile units the OSO entries aren't a reliable
69         // source of information.
70         if (cu_info->compile_units_sps.empty())
71           debug_map_sym_file->AddOSOARanges(&m_dwarf, debug_aranges);
72       }
73     }
74   }
75 
76   if (debug_aranges->GetNumRanges() == num_debug_aranges) {
77     // We got nothing from the functions, maybe we have a line tables only
78     // situation. Check the line tables and build the arange table from this.
79     SymbolContext sc;
80     sc.comp_unit = m_dwarf.GetCompUnitForDWARFCompUnit(*this);
81     if (sc.comp_unit) {
82       if (LineTable *line_table = sc.comp_unit->GetLineTable()) {
83         LineTable::FileAddressRanges file_ranges;
84         const bool append = true;
85         const size_t num_ranges =
86             line_table->GetContiguousFileAddressRanges(file_ranges, append);
87         for (uint32_t idx = 0; idx < num_ranges; ++idx) {
88           const LineTable::FileAddressRanges::Entry &range =
89               file_ranges.GetEntryRef(idx);
90           debug_aranges->AppendRange(GetOffset(), range.GetRangeBase(),
91                                      range.GetRangeEnd());
92         }
93       }
94     }
95   }
96 }
97 
98 DWARFCompileUnit &DWARFCompileUnit::GetNonSkeletonUnit() {
99   return llvm::cast<DWARFCompileUnit>(DWARFUnit::GetNonSkeletonUnit());
100 }
101 
102 DWARFDIE DWARFCompileUnit::LookupAddress(const dw_addr_t address) {
103   if (DIE()) {
104     const DWARFDebugAranges &func_aranges = GetFunctionAranges();
105 
106     // Re-check the aranges auto pointer contents in case it was created above
107     if (!func_aranges.IsEmpty())
108       return GetDIE(func_aranges.FindAddress(address));
109   }
110   return DWARFDIE();
111 }
112