1 //===-- BreakpointResolverFileLine.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 "lldb/Breakpoint/BreakpointResolverFileLine.h"
11 
12 // C Includes
13 // C++ Includes
14 // Other libraries and framework includes
15 // Project includes
16 #include "lldb/Breakpoint/BreakpointLocation.h"
17 #include "lldb/Core/Log.h"
18 #include "lldb/Core/Module.h"
19 #include "lldb/Core/StreamString.h"
20 #include "lldb/Symbol/CompileUnit.h"
21 #include "lldb/Symbol/Function.h"
22 #include "lldb/lldb-private-log.h"
23 
24 using namespace lldb;
25 using namespace lldb_private;
26 
27 //----------------------------------------------------------------------
28 // BreakpointResolverFileLine:
29 //----------------------------------------------------------------------
30 BreakpointResolverFileLine::BreakpointResolverFileLine
31 (
32     Breakpoint *bkpt,
33     const FileSpec &file_spec,
34     uint32_t line_no,
35     bool check_inlines,
36     bool skip_prologue
37 ) :
38     BreakpointResolver (bkpt, BreakpointResolver::FileLineResolver),
39     m_file_spec (file_spec),
40     m_line_number (line_no),
41     m_inlines (check_inlines),
42     m_skip_prologue(skip_prologue)
43 {
44 }
45 
46 BreakpointResolverFileLine::~BreakpointResolverFileLine ()
47 {
48 }
49 
50 Searcher::CallbackReturn
51 BreakpointResolverFileLine::SearchCallback
52 (
53     SearchFilter &filter,
54     SymbolContext &context,
55     Address *addr,
56     bool containing
57 )
58 {
59     SymbolContextList sc_list;
60 
61     assert (m_breakpoint != NULL);
62     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_BREAKPOINTS));
63 
64     // There is a tricky bit here.  You can have two compilation units that #include the same file, and
65     // in one of them the function at m_line_number is used (and so code and a line entry for it is generated) but in the
66     // other it isn't.  If we considered the CU's independently, then in the second inclusion, we'd move the breakpoint
67     // to the next function that actually generated code in the header file.  That would end up being confusing.
68     // So instead, we do the CU iterations by hand here, then scan through the complete list of matches, and figure out
69     // the closest line number match, and only set breakpoints on that match.
70 
71     // Note also that if file_spec only had a file name and not a directory, there may be many different file spec's in
72     // the resultant list.  The closest line match for one will not be right for some totally different file.
73     // So we go through the match list and pull out the sets that have the same file spec in their line_entry
74     // and treat each set separately.
75 
76     const size_t num_comp_units = context.module_sp->GetNumCompileUnits();
77     for (size_t i = 0; i < num_comp_units; i++)
78     {
79         CompUnitSP cu_sp (context.module_sp->GetCompileUnitAtIndex (i));
80         if (cu_sp)
81         {
82             if (filter.CompUnitPasses(*cu_sp))
83                 cu_sp->ResolveSymbolContext (m_file_spec, m_line_number, m_inlines, false, eSymbolContextEverything, sc_list);
84         }
85     }
86 
87     while (sc_list.GetSize() > 0)
88     {
89         SymbolContextList tmp_sc_list;
90         unsigned current_idx = 0;
91         SymbolContext sc;
92         bool first_entry = true;
93 
94         FileSpec match_file_spec;
95         uint32_t closest_line_number = UINT32_MAX;
96 
97         // Pull out the first entry, and all the others that match its file spec, and stuff them in the tmp list.
98         while (current_idx < sc_list.GetSize())
99         {
100             bool matches;
101 
102             sc_list.GetContextAtIndex (current_idx, sc);
103             if (first_entry)
104             {
105                 match_file_spec = sc.line_entry.file;
106                 matches = true;
107                 first_entry = false;
108             }
109             else
110                 matches = (sc.line_entry.file == match_file_spec);
111 
112             if (matches)
113             {
114                 tmp_sc_list.Append (sc);
115                 sc_list.RemoveContextAtIndex(current_idx);
116 
117                 // ResolveSymbolContext will always return a number that is >= the line number you pass in.
118                 // So the smaller line number is always better.
119                 if (sc.line_entry.line < closest_line_number)
120                     closest_line_number = sc.line_entry.line;
121             }
122             else
123                 current_idx++;
124         }
125 
126         // Okay, we've found the closest line number match, now throw away all the others:
127 
128         current_idx = 0;
129         while (current_idx < tmp_sc_list.GetSize())
130         {
131             if (tmp_sc_list.GetContextAtIndex(current_idx, sc))
132             {
133                 if (sc.line_entry.line != closest_line_number)
134                     tmp_sc_list.RemoveContextAtIndex(current_idx);
135                 else
136                     current_idx++;
137             }
138         }
139 
140         // Next go through and see if there are line table entries that are contiguous, and if so keep only the
141         // first of the contiguous range:
142 
143         current_idx = 0;
144         std::map<Block *, lldb::addr_t> blocks_with_breakpoints;
145 
146         while (current_idx < tmp_sc_list.GetSize())
147         {
148             if (tmp_sc_list.GetContextAtIndex(current_idx, sc))
149             {
150                 if (blocks_with_breakpoints.find (sc.block) != blocks_with_breakpoints.end())
151                     tmp_sc_list.RemoveContextAtIndex(current_idx);
152                 else
153                 {
154                     blocks_with_breakpoints.insert (std::pair<Block *, lldb::addr_t>(sc.block, sc.line_entry.range.GetBaseAddress().GetFileAddress()));
155                     current_idx++;
156                 }
157             }
158         }
159 
160         // and make breakpoints out of the closest line number match.
161 
162         uint32_t tmp_sc_list_size = tmp_sc_list.GetSize();
163 
164         for (uint32_t i = 0; i < tmp_sc_list_size; i++)
165         {
166             if (tmp_sc_list.GetContextAtIndex(i, sc))
167             {
168                 Address line_start = sc.line_entry.range.GetBaseAddress();
169                 if (line_start.IsValid())
170                 {
171                     if (filter.AddressPasses(line_start))
172                     {
173                         // If the line number is before the prologue end, move it there...
174                         bool skipped_prologue = false;
175                         if (m_skip_prologue)
176                         {
177                             if (sc.function)
178                             {
179                                 Address prologue_addr(sc.function->GetAddressRange().GetBaseAddress());
180                                 if (prologue_addr.IsValid() && (line_start == prologue_addr))
181                                 {
182                                     const uint32_t prologue_byte_size = sc.function->GetPrologueByteSize();
183                                     if (prologue_byte_size)
184                                     {
185                                         prologue_addr.Slide(prologue_byte_size);
186 
187                                         if (filter.AddressPasses(prologue_addr))
188                                         {
189                                             skipped_prologue = true;
190                                             line_start = prologue_addr;
191                                         }
192                                     }
193                                 }
194                             }
195                         }
196 
197                         BreakpointLocationSP bp_loc_sp (m_breakpoint->AddLocation(line_start));
198                         if (log && bp_loc_sp && !m_breakpoint->IsInternal())
199                         {
200                             StreamString s;
201                             bp_loc_sp->GetDescription (&s, lldb::eDescriptionLevelVerbose);
202                             log->Printf ("Added location (skipped prologue: %s): %s \n", skipped_prologue ? "yes" : "no", s.GetData());
203                         }
204                     }
205                     else if (log)
206                     {
207                         log->Printf ("Breakpoint at file address 0x%" PRIx64 " for %s:%d didn't pass the filter.\n",
208                                      line_start.GetFileAddress(),
209                                      m_file_spec.GetFilename().AsCString("<Unknown>"),
210                                      m_line_number);
211                     }
212                 }
213                 else
214                 {
215                     if (log)
216                         log->Printf ("error: Unable to set breakpoint at file address 0x%" PRIx64 " for %s:%d\n",
217                                      line_start.GetFileAddress(),
218                                      m_file_spec.GetFilename().AsCString("<Unknown>"),
219                                      m_line_number);
220                 }
221             }
222         }
223     }
224 
225     return Searcher::eCallbackReturnContinue;
226 }
227 
228 Searcher::Depth
229 BreakpointResolverFileLine::GetDepth()
230 {
231     return Searcher::eDepthModule;
232 }
233 
234 void
235 BreakpointResolverFileLine::GetDescription (Stream *s)
236 {
237     s->Printf ("file = '%s', line = %u", m_file_spec.GetPath().c_str(), m_line_number);
238 }
239 
240 void
241 BreakpointResolverFileLine::Dump (Stream *s) const
242 {
243 
244 }
245 
246