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
24using namespace lldb;
25using namespace lldb_private;
26
27//----------------------------------------------------------------------
28// BreakpointResolverFileLine:
29//----------------------------------------------------------------------
30BreakpointResolverFileLine::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
46BreakpointResolverFileLine::~BreakpointResolverFileLine ()
47{
48}
49
50Searcher::CallbackReturn
51BreakpointResolverFileLine::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        lldb::addr_t last_end_addr = LLDB_INVALID_ADDRESS;
144        current_idx = 0;
145        while (current_idx < tmp_sc_list.GetSize())
146        {
147            if (tmp_sc_list.GetContextAtIndex(current_idx, sc))
148            {
149                lldb::addr_t start_file_addr = sc.line_entry.range.GetBaseAddress().GetFileAddress();
150                lldb::addr_t end_file_addr   = start_file_addr + sc.line_entry.range.GetByteSize();
151
152                if (start_file_addr == last_end_addr)
153                    tmp_sc_list.RemoveContextAtIndex(current_idx);
154                else
155                    current_idx++;
156
157                last_end_addr = end_file_addr;
158            }
159        }
160
161        // and make breakpoints out of the closest line number match.
162
163        uint32_t tmp_sc_list_size = tmp_sc_list.GetSize();
164
165        for (uint32_t i = 0; i < tmp_sc_list_size; i++)
166        {
167            if (tmp_sc_list.GetContextAtIndex(i, sc))
168            {
169                Address line_start = sc.line_entry.range.GetBaseAddress();
170                if (line_start.IsValid())
171                {
172                    if (filter.AddressPasses(line_start))
173                    {
174                        // If the line number is before the prologue end, move it there...
175                        bool skipped_prologue = false;
176                        if (m_skip_prologue)
177                        {
178                            if (sc.function)
179                            {
180                                Address prologue_addr(sc.function->GetAddressRange().GetBaseAddress());
181                                if (prologue_addr.IsValid() && (line_start == prologue_addr))
182                                {
183                                    const uint32_t prologue_byte_size = sc.function->GetPrologueByteSize();
184                                    if (prologue_byte_size)
185                                    {
186                                        prologue_addr.Slide(prologue_byte_size);
187
188                                        if (filter.AddressPasses(prologue_addr))
189                                        {
190                                            skipped_prologue = true;
191                                            line_start = prologue_addr;
192                                        }
193                                    }
194                                }
195                            }
196                        }
197
198                        BreakpointLocationSP bp_loc_sp (m_breakpoint->AddLocation(line_start));
199                        if (log && bp_loc_sp && !m_breakpoint->IsInternal())
200                        {
201                            StreamString s;
202                            bp_loc_sp->GetDescription (&s, lldb::eDescriptionLevelVerbose);
203                            log->Printf ("Added location (skipped prologue: %s): %s \n", skipped_prologue ? "yes" : "no", s.GetData());
204                        }
205                    }
206                    else if (log)
207                    {
208                        log->Printf ("Breakpoint at file address 0x%" PRIx64 " for %s:%d didn't pass the filter.\n",
209                                     line_start.GetFileAddress(),
210                                     m_file_spec.GetFilename().AsCString("<Unknown>"),
211                                     m_line_number);
212                    }
213                }
214                else
215                {
216                    if (log)
217                        log->Printf ("error: Unable to set breakpoint at file address 0x%" PRIx64 " for %s:%d\n",
218                                     line_start.GetFileAddress(),
219                                     m_file_spec.GetFilename().AsCString("<Unknown>"),
220                                     m_line_number);
221                }
222            }
223        }
224    }
225
226    return Searcher::eCallbackReturnContinue;
227}
228
229Searcher::Depth
230BreakpointResolverFileLine::GetDepth()
231{
232    return Searcher::eDepthModule;
233}
234
235void
236BreakpointResolverFileLine::GetDescription (Stream *s)
237{
238    s->Printf ("file = '%s', line = %u", m_file_spec.GetPath().c_str(), m_line_number);
239}
240
241void
242BreakpointResolverFileLine::Dump (Stream *s) const
243{
244
245}
246
247