1 //===-- DWARFCompileUnit.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 #include "DWARFCompileUnit.h"
11 
12 #include "SymbolFileDWARF.h"
13 
14 using namespace lldb;
15 using namespace lldb_private;
16 
17 extern int g_verbose;
18 
19 DWARFCompileUnit::DWARFCompileUnit(SymbolFileDWARF *dwarf2Data)
20     : DWARFUnit(dwarf2Data) {}
21 
22 DWARFUnitSP DWARFCompileUnit::Extract(SymbolFileDWARF *dwarf2Data,
23     lldb::offset_t *offset_ptr) {
24   // std::make_shared would require the ctor to be public.
25   std::shared_ptr<DWARFCompileUnit> cu_sp(new DWARFCompileUnit(dwarf2Data));
26   // Out of memory?
27   if (cu_sp.get() == NULL)
28     return nullptr;
29 
30   const DWARFDataExtractor &debug_info = dwarf2Data->get_debug_info_data();
31 
32   cu_sp->m_offset = *offset_ptr;
33 
34   if (debug_info.ValidOffset(*offset_ptr)) {
35     dw_offset_t abbr_offset;
36     const DWARFDebugAbbrev *abbr = dwarf2Data->DebugAbbrev();
37     cu_sp->m_length = debug_info.GetDWARFInitialLength(offset_ptr);
38     cu_sp->m_is_dwarf64 = debug_info.IsDWARF64();
39     cu_sp->m_version = debug_info.GetU16(offset_ptr);
40     abbr_offset = debug_info.GetDWARFOffset(offset_ptr);
41     cu_sp->m_addr_size = debug_info.GetU8(offset_ptr);
42 
43     bool length_OK =
44         debug_info.ValidOffset(cu_sp->GetNextCompileUnitOffset() - 1);
45     bool version_OK = SymbolFileDWARF::SupportedVersion(cu_sp->m_version);
46     bool abbr_offset_OK =
47         dwarf2Data->get_debug_abbrev_data().ValidOffset(abbr_offset);
48     bool addr_size_OK = (cu_sp->m_addr_size == 4) || (cu_sp->m_addr_size == 8);
49 
50     if (length_OK && version_OK && addr_size_OK && abbr_offset_OK &&
51         abbr != NULL) {
52       cu_sp->m_abbrevs = abbr->GetAbbreviationDeclarationSet(abbr_offset);
53       return cu_sp;
54     }
55 
56     // reset the offset to where we tried to parse from if anything went wrong
57     *offset_ptr = cu_sp->m_offset;
58   }
59 
60   return nullptr;
61 }
62 
63 void DWARFCompileUnit::Dump(Stream *s) const {
64   s->Printf("0x%8.8x: Compile Unit: length = 0x%8.8x, version = 0x%4.4x, "
65             "abbr_offset = 0x%8.8x, addr_size = 0x%2.2x (next CU at "
66             "{0x%8.8x})\n",
67             m_offset, m_length, m_version, GetAbbrevOffset(), m_addr_size,
68             GetNextCompileUnitOffset());
69 }
70