1 //===-- CompileUnitIndex.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 "CompileUnitIndex.h"
11 
12 #include "PdbIndex.h"
13 #include "PdbUtil.h"
14 
15 #include "llvm/DebugInfo/CodeView/LazyRandomTypeCollection.h"
16 #include "llvm/DebugInfo/CodeView/SymbolDeserializer.h"
17 #include "llvm/DebugInfo/CodeView/TypeDeserializer.h"
18 #include "llvm/DebugInfo/MSF/MappedBlockStream.h"
19 #include "llvm/DebugInfo/PDB/Native/DbiModuleDescriptor.h"
20 #include "llvm/DebugInfo/PDB/Native/DbiStream.h"
21 #include "llvm/DebugInfo/PDB/Native/InfoStream.h"
22 #include "llvm/DebugInfo/PDB/Native/ModuleDebugStream.h"
23 #include "llvm/DebugInfo/PDB/Native/NamedStreamMap.h"
24 #include "llvm/DebugInfo/PDB/Native/TpiStream.h"
25 #include "llvm/Support/Path.h"
26 
27 #include "lldb/Utility/LLDBAssert.h"
28 
29 using namespace lldb;
30 using namespace lldb_private;
31 using namespace lldb_private::npdb;
32 using namespace llvm::codeview;
33 using namespace llvm::pdb;
34 
IsMainFile(llvm::StringRef main,llvm::StringRef other)35 static bool IsMainFile(llvm::StringRef main, llvm::StringRef other) {
36   if (main == other)
37     return true;
38 
39   // If the files refer to the local file system, we can just ask the file
40   // system if they're equivalent.  But if the source isn't present on disk
41   // then we still want to try.
42   if (llvm::sys::fs::equivalent(main, other))
43     return true;
44 
45   llvm::SmallString<64> normalized(other);
46   llvm::sys::path::native(normalized);
47   return main.equals_lower(normalized);
48 }
49 
ParseCompile3(const CVSymbol & sym,CompilandIndexItem & cci)50 static void ParseCompile3(const CVSymbol &sym, CompilandIndexItem &cci) {
51   cci.m_compile_opts.emplace();
52   llvm::cantFail(
53       SymbolDeserializer::deserializeAs<Compile3Sym>(sym, *cci.m_compile_opts));
54 }
55 
ParseObjname(const CVSymbol & sym,CompilandIndexItem & cci)56 static void ParseObjname(const CVSymbol &sym, CompilandIndexItem &cci) {
57   cci.m_obj_name.emplace();
58   llvm::cantFail(
59       SymbolDeserializer::deserializeAs<ObjNameSym>(sym, *cci.m_obj_name));
60 }
61 
ParseBuildInfo(PdbIndex & index,const CVSymbol & sym,CompilandIndexItem & cci)62 static void ParseBuildInfo(PdbIndex &index, const CVSymbol &sym,
63                            CompilandIndexItem &cci) {
64   BuildInfoSym bis(SymbolRecordKind::BuildInfoSym);
65   llvm::cantFail(SymbolDeserializer::deserializeAs<BuildInfoSym>(sym, bis));
66 
67   // S_BUILDINFO just points to an LF_BUILDINFO in the IPI stream.  Let's do
68   // a little extra work to pull out the LF_BUILDINFO.
69   LazyRandomTypeCollection &types = index.ipi().typeCollection();
70   llvm::Optional<CVType> cvt = types.tryGetType(bis.BuildId);
71 
72   if (!cvt || cvt->kind() != LF_BUILDINFO)
73     return;
74 
75   BuildInfoRecord bir;
76   llvm::cantFail(TypeDeserializer::deserializeAs<BuildInfoRecord>(*cvt, bir));
77   cci.m_build_info.assign(bir.ArgIndices.begin(), bir.ArgIndices.end());
78 }
79 
ParseExtendedInfo(PdbIndex & index,CompilandIndexItem & item)80 static void ParseExtendedInfo(PdbIndex &index, CompilandIndexItem &item) {
81   const CVSymbolArray &syms = item.m_debug_stream.getSymbolArray();
82 
83   // This is a private function, it shouldn't be called if the information
84   // has already been parsed.
85   lldbassert(!item.m_obj_name);
86   lldbassert(!item.m_compile_opts);
87   lldbassert(item.m_build_info.empty());
88 
89   // We're looking for 3 things.  S_COMPILE3, S_OBJNAME, and S_BUILDINFO.
90   int found = 0;
91   for (const CVSymbol &sym : syms) {
92     switch (sym.kind()) {
93     case S_COMPILE3:
94       ParseCompile3(sym, item);
95       break;
96     case S_OBJNAME:
97       ParseObjname(sym, item);
98       break;
99     case S_BUILDINFO:
100       ParseBuildInfo(index, sym, item);
101       break;
102     default:
103       continue;
104     }
105     if (++found >= 3)
106       break;
107   }
108 }
109 
CompilandIndexItem(PdbCompilandId id,llvm::pdb::ModuleDebugStreamRef debug_stream,llvm::pdb::DbiModuleDescriptor descriptor)110 CompilandIndexItem::CompilandIndexItem(
111     PdbCompilandId id, llvm::pdb::ModuleDebugStreamRef debug_stream,
112     llvm::pdb::DbiModuleDescriptor descriptor)
113     : m_id(id), m_debug_stream(std::move(debug_stream)),
114       m_module_descriptor(std::move(descriptor)) {}
115 
GetOrCreateCompiland(uint16_t modi)116 CompilandIndexItem &CompileUnitIndex::GetOrCreateCompiland(uint16_t modi) {
117   auto result = m_comp_units.try_emplace(modi, nullptr);
118   if (!result.second)
119     return *result.first->second;
120 
121   // Find the module list and load its debug information stream and cache it
122   // since we need to use it for almost all interesting operations.
123   const DbiModuleList &modules = m_index.dbi().modules();
124   llvm::pdb::DbiModuleDescriptor descriptor = modules.getModuleDescriptor(modi);
125   uint16_t stream = descriptor.getModuleStreamIndex();
126   std::unique_ptr<llvm::msf::MappedBlockStream> stream_data =
127       m_index.pdb().createIndexedStream(stream);
128   llvm::pdb::ModuleDebugStreamRef debug_stream(descriptor,
129                                                std::move(stream_data));
130   cantFail(debug_stream.reload());
131 
132   std::unique_ptr<CompilandIndexItem> &cci = result.first->second;
133 
134   cci = llvm::make_unique<CompilandIndexItem>(
135       PdbCompilandId{modi}, std::move(debug_stream), std::move(descriptor));
136   ParseExtendedInfo(m_index, *cci);
137 
138   cci->m_strings.initialize(debug_stream.getSubsectionsArray());
139   PDBStringTable &strings = cantFail(m_index.pdb().getStringTable());
140   cci->m_strings.setStrings(strings.getStringTable());
141 
142   // We want the main source file to always comes first.  Note that we can't
143   // just push_back the main file onto the front because `GetMainSourceFile`
144   // computes it in such a way that it doesn't own the resulting memory.  So we
145   // have to iterate the module file list comparing each one to the main file
146   // name until we find it, and we can cache that one since the memory is backed
147   // by a contiguous chunk inside the mapped PDB.
148   llvm::SmallString<64> main_file = GetMainSourceFile(*cci);
149   std::string s = main_file.str();
150   llvm::sys::path::native(main_file);
151 
152   uint32_t file_count = modules.getSourceFileCount(modi);
153   cci->m_file_list.reserve(file_count);
154   bool found_main_file = false;
155   for (llvm::StringRef file : modules.source_files(modi)) {
156     if (!found_main_file && IsMainFile(main_file, file)) {
157       cci->m_file_list.insert(cci->m_file_list.begin(), file);
158       found_main_file = true;
159       continue;
160     }
161     cci->m_file_list.push_back(file);
162   }
163 
164   return *cci;
165 }
166 
GetCompiland(uint16_t modi) const167 const CompilandIndexItem *CompileUnitIndex::GetCompiland(uint16_t modi) const {
168   auto iter = m_comp_units.find(modi);
169   if (iter == m_comp_units.end())
170     return nullptr;
171   return iter->second.get();
172 }
173 
GetCompiland(uint16_t modi)174 CompilandIndexItem *CompileUnitIndex::GetCompiland(uint16_t modi) {
175   auto iter = m_comp_units.find(modi);
176   if (iter == m_comp_units.end())
177     return nullptr;
178   return iter->second.get();
179 }
180 
181 llvm::SmallString<64>
GetMainSourceFile(const CompilandIndexItem & item) const182 CompileUnitIndex::GetMainSourceFile(const CompilandIndexItem &item) const {
183   // LF_BUILDINFO contains a list of arg indices which point to LF_STRING_ID
184   // records in the IPI stream.  The order of the arg indices is as follows:
185   // [0] - working directory where compiler was invoked.
186   // [1] - absolute path to compiler binary
187   // [2] - source file name
188   // [3] - path to compiler generated PDB (the /Zi PDB, although this entry gets
189   //       added even when using /Z7)
190   // [4] - full command line invocation.
191   //
192   // We need to form the path [0]\[2] to generate the full path to the main
193   // file.source
194   if (item.m_build_info.size() < 3)
195     return {""};
196 
197   LazyRandomTypeCollection &types = m_index.ipi().typeCollection();
198 
199   StringIdRecord working_dir;
200   StringIdRecord file_name;
201   CVType dir_cvt = types.getType(item.m_build_info[0]);
202   CVType file_cvt = types.getType(item.m_build_info[2]);
203   llvm::cantFail(
204       TypeDeserializer::deserializeAs<StringIdRecord>(dir_cvt, working_dir));
205   llvm::cantFail(
206       TypeDeserializer::deserializeAs<StringIdRecord>(file_cvt, file_name));
207 
208   llvm::sys::path::Style style = working_dir.String.startswith("/")
209                                      ? llvm::sys::path::Style::posix
210                                      : llvm::sys::path::Style::windows;
211   if (llvm::sys::path::is_absolute(file_name.String, style))
212     return file_name.String;
213 
214   llvm::SmallString<64> absolute_path = working_dir.String;
215   llvm::sys::path::append(absolute_path, file_name.String);
216   return absolute_path;
217 }
218