xref: /freebsd-src/contrib/llvm-project/lldb/source/Breakpoint/BreakpointResolverFileLine.cpp (revision 2eb4d8dc723da3cf7d735a3226ae49da4c8c5dbc)
1 //===-- BreakpointResolverFileLine.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 "lldb/Breakpoint/BreakpointResolverFileLine.h"
10 
11 #include "lldb/Breakpoint/BreakpointLocation.h"
12 #include "lldb/Core/Module.h"
13 #include "lldb/Symbol/CompileUnit.h"
14 #include "lldb/Symbol/Function.h"
15 #include "lldb/Utility/Log.h"
16 #include "lldb/Utility/StreamString.h"
17 
18 using namespace lldb;
19 using namespace lldb_private;
20 
21 // BreakpointResolverFileLine:
22 BreakpointResolverFileLine::BreakpointResolverFileLine(
23     const BreakpointSP &bkpt, const FileSpec &file_spec, uint32_t line_no,
24     uint32_t column, lldb::addr_t offset, bool check_inlines,
25     bool skip_prologue, bool exact_match)
26     : BreakpointResolver(bkpt, BreakpointResolver::FileLineResolver, offset),
27       m_file_spec(file_spec), m_line_number(line_no), m_column(column),
28       m_inlines(check_inlines), m_skip_prologue(skip_prologue),
29       m_exact_match(exact_match) {}
30 
31 BreakpointResolver *BreakpointResolverFileLine::CreateFromStructuredData(
32     const BreakpointSP &bkpt, const StructuredData::Dictionary &options_dict,
33     Status &error) {
34   llvm::StringRef filename;
35   uint32_t line_no;
36   uint32_t column;
37   bool check_inlines;
38   bool skip_prologue;
39   bool exact_match;
40   bool success;
41 
42   lldb::addr_t offset = 0;
43 
44   success = options_dict.GetValueForKeyAsString(GetKey(OptionNames::FileName),
45                                                 filename);
46   if (!success) {
47     error.SetErrorString("BRFL::CFSD: Couldn't find filename entry.");
48     return nullptr;
49   }
50 
51   success = options_dict.GetValueForKeyAsInteger(
52       GetKey(OptionNames::LineNumber), line_no);
53   if (!success) {
54     error.SetErrorString("BRFL::CFSD: Couldn't find line number entry.");
55     return nullptr;
56   }
57 
58   success =
59       options_dict.GetValueForKeyAsInteger(GetKey(OptionNames::Column), column);
60   if (!success) {
61     // Backwards compatibility.
62     column = 0;
63   }
64 
65   success = options_dict.GetValueForKeyAsBoolean(GetKey(OptionNames::Inlines),
66                                                  check_inlines);
67   if (!success) {
68     error.SetErrorString("BRFL::CFSD: Couldn't find check inlines entry.");
69     return nullptr;
70   }
71 
72   success = options_dict.GetValueForKeyAsBoolean(
73       GetKey(OptionNames::SkipPrologue), skip_prologue);
74   if (!success) {
75     error.SetErrorString("BRFL::CFSD: Couldn't find skip prologue entry.");
76     return nullptr;
77   }
78 
79   success = options_dict.GetValueForKeyAsBoolean(
80       GetKey(OptionNames::ExactMatch), exact_match);
81   if (!success) {
82     error.SetErrorString("BRFL::CFSD: Couldn't find exact match entry.");
83     return nullptr;
84   }
85 
86   FileSpec file_spec(filename);
87 
88   return new BreakpointResolverFileLine(bkpt, file_spec, line_no, column,
89                                         offset, check_inlines, skip_prologue,
90                                         exact_match);
91 }
92 
93 StructuredData::ObjectSP
94 BreakpointResolverFileLine::SerializeToStructuredData() {
95   StructuredData::DictionarySP options_dict_sp(
96       new StructuredData::Dictionary());
97 
98   options_dict_sp->AddStringItem(GetKey(OptionNames::FileName),
99                                  m_file_spec.GetPath());
100   options_dict_sp->AddIntegerItem(GetKey(OptionNames::LineNumber),
101                                   m_line_number);
102   options_dict_sp->AddIntegerItem(GetKey(OptionNames::Column),
103                                   m_column);
104   options_dict_sp->AddBooleanItem(GetKey(OptionNames::Inlines), m_inlines);
105   options_dict_sp->AddBooleanItem(GetKey(OptionNames::SkipPrologue),
106                                   m_skip_prologue);
107   options_dict_sp->AddBooleanItem(GetKey(OptionNames::ExactMatch),
108                                   m_exact_match);
109 
110   return WrapOptionsDict(options_dict_sp);
111 }
112 
113 // Filter the symbol context list to remove contexts where the line number was
114 // moved into a new function. We do this conservatively, so if e.g. we cannot
115 // resolve the function in the context (which can happen in case of line-table-
116 // only debug info), we leave the context as is. The trickiest part here is
117 // handling inlined functions -- in this case we need to make sure we look at
118 // the declaration line of the inlined function, NOT the function it was
119 // inlined into.
120 void BreakpointResolverFileLine::FilterContexts(SymbolContextList &sc_list,
121                                                 bool is_relative) {
122   if (m_exact_match)
123     return; // Nothing to do. Contexts are precise.
124 
125   llvm::StringRef relative_path;
126   if (is_relative)
127     relative_path = m_file_spec.GetDirectory().GetStringRef();
128 
129   Log * log = GetLogIfAllCategoriesSet(LIBLLDB_LOG_BREAKPOINTS);
130   for(uint32_t i = 0; i < sc_list.GetSize(); ++i) {
131     SymbolContext sc;
132     sc_list.GetContextAtIndex(i, sc);
133     if (is_relative) {
134       // If the path was relative, make sure any matches match as long as the
135       // relative parts of the path match the path from support files
136       auto sc_dir = sc.line_entry.file.GetDirectory().GetStringRef();
137       if (!sc_dir.endswith(relative_path)) {
138         // We had a relative path specified and the relative directory doesn't
139         // match so remove this one
140         LLDB_LOG(log, "removing not matching relative path {0} since it "
141                 "doesn't end with {1}", sc_dir, relative_path);
142         sc_list.RemoveContextAtIndex(i);
143         --i;
144         continue;
145       }
146     }
147 
148     if (!sc.block)
149       continue;
150 
151     FileSpec file;
152     uint32_t line;
153     const Block *inline_block = sc.block->GetContainingInlinedBlock();
154     if (inline_block) {
155       const Declaration &inline_declaration = inline_block->GetInlinedFunctionInfo()->GetDeclaration();
156       if (!inline_declaration.IsValid())
157         continue;
158       file = inline_declaration.GetFile();
159       line = inline_declaration.GetLine();
160     } else if (sc.function)
161       sc.function->GetStartLineSourceInfo(file, line);
162     else
163       continue;
164 
165     if (file != sc.line_entry.file) {
166       LLDB_LOG(log, "unexpected symbol context file {0}", sc.line_entry.file);
167       continue;
168     }
169 
170     // Compare the requested line number with the line of the function
171     // declaration. In case of a function declared as:
172     //
173     // int
174     // foo()
175     // {
176     //   ...
177     //
178     // the compiler will set the declaration line to the "foo" line, which is
179     // the reason why we have -1 here. This can fail in case of two inline
180     // functions defined back-to-back:
181     //
182     // inline int foo1() { ... }
183     // inline int foo2() { ... }
184     //
185     // but that's the best we can do for now.
186     // One complication, if the line number returned from GetStartLineSourceInfo
187     // is 0, then we can't do this calculation.  That can happen if
188     // GetStartLineSourceInfo gets an error, or if the first line number in
189     // the function really is 0 - which happens for some languages.
190 
191     // But only do this calculation if the line number we found in the SC
192     // was different from the one requested in the source file.  If we actually
193     // found an exact match it must be valid.
194 
195     if (m_line_number == sc.line_entry.line)
196       continue;
197 
198     const int decl_line_is_too_late_fudge = 1;
199     if (line && m_line_number < line - decl_line_is_too_late_fudge) {
200       LLDB_LOG(log, "removing symbol context at {0}:{1}", file, line);
201       sc_list.RemoveContextAtIndex(i);
202       --i;
203     }
204   }
205 }
206 
207 Searcher::CallbackReturn BreakpointResolverFileLine::SearchCallback(
208     SearchFilter &filter, SymbolContext &context, Address *addr) {
209   SymbolContextList sc_list;
210 
211   // There is a tricky bit here.  You can have two compilation units that
212   // #include the same file, and in one of them the function at m_line_number
213   // is used (and so code and a line entry for it is generated) but in the
214   // other it isn't.  If we considered the CU's independently, then in the
215   // second inclusion, we'd move the breakpoint to the next function that
216   // actually generated code in the header file.  That would end up being
217   // confusing.  So instead, we do the CU iterations by hand here, then scan
218   // through the complete list of matches, and figure out the closest line
219   // number match, and only set breakpoints on that match.
220 
221   // Note also that if file_spec only had a file name and not a directory,
222   // there may be many different file spec's in the resultant list.  The
223   // closest line match for one will not be right for some totally different
224   // file.  So we go through the match list and pull out the sets that have the
225   // same file spec in their line_entry and treat each set separately.
226 
227   FileSpec search_file_spec = m_file_spec;
228   const bool is_relative = m_file_spec.IsRelative();
229   if (is_relative)
230     search_file_spec.GetDirectory().Clear();
231 
232   const size_t num_comp_units = context.module_sp->GetNumCompileUnits();
233   for (size_t i = 0; i < num_comp_units; i++) {
234     CompUnitSP cu_sp(context.module_sp->GetCompileUnitAtIndex(i));
235     if (cu_sp) {
236       if (filter.CompUnitPasses(*cu_sp))
237         cu_sp->ResolveSymbolContext(search_file_spec, m_line_number, m_inlines,
238                                     m_exact_match, eSymbolContextEverything,
239                                     sc_list);
240     }
241   }
242 
243   FilterContexts(sc_list, is_relative);
244 
245   StreamString s;
246   s.Printf("for %s:%d ", m_file_spec.GetFilename().AsCString("<Unknown>"),
247            m_line_number);
248 
249   SetSCMatchesByLine(filter, sc_list, m_skip_prologue, s.GetString(),
250                      m_line_number, m_column);
251 
252   return Searcher::eCallbackReturnContinue;
253 }
254 
255 lldb::SearchDepth BreakpointResolverFileLine::GetDepth() {
256   return lldb::eSearchDepthModule;
257 }
258 
259 void BreakpointResolverFileLine::GetDescription(Stream *s) {
260   s->Printf("file = '%s', line = %u, ", m_file_spec.GetPath().c_str(),
261             m_line_number);
262   if (m_column)
263     s->Printf("column = %u, ", m_column);
264   s->Printf("exact_match = %d", m_exact_match);
265 }
266 
267 void BreakpointResolverFileLine::Dump(Stream *s) const {}
268 
269 lldb::BreakpointResolverSP
270 BreakpointResolverFileLine::CopyForBreakpoint(BreakpointSP &breakpoint) {
271   lldb::BreakpointResolverSP ret_sp(new BreakpointResolverFileLine(
272       breakpoint, m_file_spec, m_line_number, m_column, GetOffset(), m_inlines,
273       m_skip_prologue, m_exact_match));
274 
275   return ret_sp;
276 }
277