1 //===-- DWARFDebugLine.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 "DWARFDebugLine.h"
11
12 //#define ENABLE_DEBUG_PRINTF // DO NOT LEAVE THIS DEFINED: DEBUG ONLY!!!
13 #include <assert.h>
14
15 #include "lldb/Core/FileSpecList.h"
16 #include "lldb/Core/Log.h"
17 #include "lldb/Core/Module.h"
18 #include "lldb/Core/Timer.h"
19 #include "lldb/Host/Host.h"
20
21 #include "SymbolFileDWARF.h"
22 #include "LogChannelDWARF.h"
23
24 using namespace lldb;
25 using namespace lldb_private;
26 using namespace std;
27
28 //----------------------------------------------------------------------
29 // Parse
30 //
31 // Parse all information in the debug_line_data into an internal
32 // representation.
33 //----------------------------------------------------------------------
34 void
Parse(const DataExtractor & debug_line_data)35 DWARFDebugLine::Parse(const DataExtractor& debug_line_data)
36 {
37 m_lineTableMap.clear();
38 lldb::offset_t offset = 0;
39 LineTable::shared_ptr line_table_sp(new LineTable);
40 while (debug_line_data.ValidOffset(offset))
41 {
42 const lldb::offset_t debug_line_offset = offset;
43
44 if (line_table_sp.get() == NULL)
45 break;
46
47 if (ParseStatementTable(debug_line_data, &offset, line_table_sp.get()))
48 {
49 // Make sure we don't don't loop infinitely
50 if (offset <= debug_line_offset)
51 break;
52 //DEBUG_PRINTF("m_lineTableMap[0x%8.8x] = line_table_sp\n", debug_line_offset);
53 m_lineTableMap[debug_line_offset] = line_table_sp;
54 line_table_sp.reset(new LineTable);
55 }
56 else
57 ++offset; // Try next byte in line table
58 }
59 }
60
61 void
ParseIfNeeded(const DataExtractor & debug_line_data)62 DWARFDebugLine::ParseIfNeeded(const DataExtractor& debug_line_data)
63 {
64 if (m_lineTableMap.empty())
65 Parse(debug_line_data);
66 }
67
68
69 //----------------------------------------------------------------------
70 // DWARFDebugLine::GetLineTable
71 //----------------------------------------------------------------------
72 DWARFDebugLine::LineTable::shared_ptr
GetLineTable(const dw_offset_t offset) const73 DWARFDebugLine::GetLineTable(const dw_offset_t offset) const
74 {
75 DWARFDebugLine::LineTable::shared_ptr line_table_shared_ptr;
76 LineTableConstIter pos = m_lineTableMap.find(offset);
77 if (pos != m_lineTableMap.end())
78 line_table_shared_ptr = pos->second;
79 return line_table_shared_ptr;
80 }
81
82
83 //----------------------------------------------------------------------
84 // DumpStateToFile
85 //----------------------------------------------------------------------
86 static void
DumpStateToFile(dw_offset_t offset,const DWARFDebugLine::State & state,void * userData)87 DumpStateToFile (dw_offset_t offset, const DWARFDebugLine::State& state, void* userData)
88 {
89 Log *log = (Log *)userData;
90 if (state.row == DWARFDebugLine::State::StartParsingLineTable)
91 {
92 // If the row is zero we are being called with the prologue only
93 state.prologue->Dump (log);
94 log->PutCString ("Address Line Column File");
95 log->PutCString ("------------------ ------ ------ ------");
96 }
97 else if (state.row == DWARFDebugLine::State::DoneParsingLineTable)
98 {
99 // Done parsing line table
100 }
101 else
102 {
103 log->Printf( "0x%16.16" PRIx64 " %6u %6u %6u%s\n", state.address, state.line, state.column, state.file, state.end_sequence ? " END" : "");
104 }
105 }
106
107 //----------------------------------------------------------------------
108 // DWARFDebugLine::DumpLineTableRows
109 //----------------------------------------------------------------------
110 bool
DumpLineTableRows(Log * log,SymbolFileDWARF * dwarf2Data,dw_offset_t debug_line_offset)111 DWARFDebugLine::DumpLineTableRows(Log *log, SymbolFileDWARF* dwarf2Data, dw_offset_t debug_line_offset)
112 {
113 const DataExtractor& debug_line_data = dwarf2Data->get_debug_line_data();
114
115 if (debug_line_offset == DW_INVALID_OFFSET)
116 {
117 // Dump line table to a single file only
118 debug_line_offset = 0;
119 while (debug_line_data.ValidOffset(debug_line_offset))
120 debug_line_offset = DumpStatementTable (log, debug_line_data, debug_line_offset);
121 }
122 else
123 {
124 // Dump line table to a single file only
125 DumpStatementTable (log, debug_line_data, debug_line_offset);
126 }
127 return false;
128 }
129
130 //----------------------------------------------------------------------
131 // DWARFDebugLine::DumpStatementTable
132 //----------------------------------------------------------------------
133 dw_offset_t
DumpStatementTable(Log * log,const DataExtractor & debug_line_data,const dw_offset_t debug_line_offset)134 DWARFDebugLine::DumpStatementTable(Log *log, const DataExtractor& debug_line_data, const dw_offset_t debug_line_offset)
135 {
136 if (debug_line_data.ValidOffset(debug_line_offset))
137 {
138 lldb::offset_t offset = debug_line_offset;
139 log->Printf( "----------------------------------------------------------------------\n"
140 "debug_line[0x%8.8x]\n"
141 "----------------------------------------------------------------------\n", debug_line_offset);
142
143 if (ParseStatementTable(debug_line_data, &offset, DumpStateToFile, log))
144 return offset;
145 else
146 return debug_line_offset + 1; // Skip to next byte in .debug_line section
147 }
148
149 return DW_INVALID_OFFSET;
150 }
151
152
153 //----------------------------------------------------------------------
154 // DumpOpcodes
155 //----------------------------------------------------------------------
156 bool
DumpOpcodes(Log * log,SymbolFileDWARF * dwarf2Data,dw_offset_t debug_line_offset,uint32_t dump_flags)157 DWARFDebugLine::DumpOpcodes(Log *log, SymbolFileDWARF* dwarf2Data, dw_offset_t debug_line_offset, uint32_t dump_flags)
158 {
159 const DataExtractor& debug_line_data = dwarf2Data->get_debug_line_data();
160
161 if (debug_line_data.GetByteSize() == 0)
162 {
163 log->Printf( "< EMPTY >\n");
164 return false;
165 }
166
167 if (debug_line_offset == DW_INVALID_OFFSET)
168 {
169 // Dump line table to a single file only
170 debug_line_offset = 0;
171 while (debug_line_data.ValidOffset(debug_line_offset))
172 debug_line_offset = DumpStatementOpcodes (log, debug_line_data, debug_line_offset, dump_flags);
173 }
174 else
175 {
176 // Dump line table to a single file only
177 DumpStatementOpcodes (log, debug_line_data, debug_line_offset, dump_flags);
178 }
179 return false;
180 }
181
182 //----------------------------------------------------------------------
183 // DumpStatementOpcodes
184 //----------------------------------------------------------------------
185 dw_offset_t
DumpStatementOpcodes(Log * log,const DataExtractor & debug_line_data,const dw_offset_t debug_line_offset,uint32_t flags)186 DWARFDebugLine::DumpStatementOpcodes(Log *log, const DataExtractor& debug_line_data, const dw_offset_t debug_line_offset, uint32_t flags)
187 {
188 lldb::offset_t offset = debug_line_offset;
189 if (debug_line_data.ValidOffset(offset))
190 {
191 Prologue prologue;
192
193 if (ParsePrologue(debug_line_data, &offset, &prologue))
194 {
195 log->PutCString ("----------------------------------------------------------------------");
196 log->Printf ("debug_line[0x%8.8x]", debug_line_offset);
197 log->PutCString ("----------------------------------------------------------------------\n");
198 prologue.Dump (log);
199 }
200 else
201 {
202 offset = debug_line_offset;
203 log->Printf( "0x%8.8" PRIx64 ": skipping pad byte %2.2x", offset, debug_line_data.GetU8(&offset));
204 return offset;
205 }
206
207 Row row(prologue.default_is_stmt);
208 const dw_offset_t end_offset = debug_line_offset + prologue.total_length + sizeof(prologue.total_length);
209
210 assert(debug_line_data.ValidOffset(end_offset-1));
211
212 while (offset < end_offset)
213 {
214 const uint32_t op_offset = offset;
215 uint8_t opcode = debug_line_data.GetU8(&offset);
216 switch (opcode)
217 {
218 case 0: // Extended Opcodes always start with a zero opcode followed by
219 { // a uleb128 length so you can skip ones you don't know about
220
221 dw_offset_t ext_offset = offset;
222 dw_uleb128_t len = debug_line_data.GetULEB128(&offset);
223 dw_offset_t arg_size = len - (offset - ext_offset);
224 uint8_t sub_opcode = debug_line_data.GetU8(&offset);
225 // if (verbose)
226 // log->Printf( "Extended: <%u> %2.2x ", len, sub_opcode);
227
228 switch (sub_opcode)
229 {
230 case DW_LNE_end_sequence :
231 log->Printf( "0x%8.8x: DW_LNE_end_sequence", op_offset);
232 row.Dump(log);
233 row.Reset(prologue.default_is_stmt);
234 break;
235
236 case DW_LNE_set_address :
237 {
238 row.address = debug_line_data.GetMaxU64(&offset, arg_size);
239 log->Printf( "0x%8.8x: DW_LNE_set_address (0x%" PRIx64 ")", op_offset, row.address);
240 }
241 break;
242
243 case DW_LNE_define_file:
244 {
245 FileNameEntry fileEntry;
246 fileEntry.name = debug_line_data.GetCStr(&offset);
247 fileEntry.dir_idx = debug_line_data.GetULEB128(&offset);
248 fileEntry.mod_time = debug_line_data.GetULEB128(&offset);
249 fileEntry.length = debug_line_data.GetULEB128(&offset);
250 log->Printf( "0x%8.8x: DW_LNE_define_file('%s', dir=%i, mod_time=0x%8.8x, length=%i )",
251 op_offset,
252 fileEntry.name.c_str(),
253 fileEntry.dir_idx,
254 fileEntry.mod_time,
255 fileEntry.length);
256 prologue.file_names.push_back(fileEntry);
257 }
258 break;
259
260 default:
261 log->Printf( "0x%8.8x: DW_LNE_??? (%2.2x) - Skipping unknown upcode", op_offset, opcode);
262 // Length doesn't include the zero opcode byte or the length itself, but
263 // it does include the sub_opcode, so we have to adjust for that below
264 offset += arg_size;
265 break;
266 }
267 }
268 break;
269
270 // Standard Opcodes
271 case DW_LNS_copy:
272 log->Printf( "0x%8.8x: DW_LNS_copy", op_offset);
273 row.Dump (log);
274 break;
275
276 case DW_LNS_advance_pc:
277 {
278 dw_uleb128_t addr_offset_n = debug_line_data.GetULEB128(&offset);
279 dw_uleb128_t addr_offset = addr_offset_n * prologue.min_inst_length;
280 log->Printf( "0x%8.8x: DW_LNS_advance_pc (0x%x)", op_offset, addr_offset);
281 row.address += addr_offset;
282 }
283 break;
284
285 case DW_LNS_advance_line:
286 {
287 dw_sleb128_t line_offset = debug_line_data.GetSLEB128(&offset);
288 log->Printf( "0x%8.8x: DW_LNS_advance_line (%i)", op_offset, line_offset);
289 row.line += line_offset;
290 }
291 break;
292
293 case DW_LNS_set_file:
294 row.file = debug_line_data.GetULEB128(&offset);
295 log->Printf( "0x%8.8x: DW_LNS_set_file (%u)", op_offset, row.file);
296 break;
297
298 case DW_LNS_set_column:
299 row.column = debug_line_data.GetULEB128(&offset);
300 log->Printf( "0x%8.8x: DW_LNS_set_column (%u)", op_offset, row.column);
301 break;
302
303 case DW_LNS_negate_stmt:
304 row.is_stmt = !row.is_stmt;
305 log->Printf( "0x%8.8x: DW_LNS_negate_stmt", op_offset);
306 break;
307
308 case DW_LNS_set_basic_block:
309 row.basic_block = true;
310 log->Printf( "0x%8.8x: DW_LNS_set_basic_block", op_offset);
311 break;
312
313 case DW_LNS_const_add_pc:
314 {
315 uint8_t adjust_opcode = 255 - prologue.opcode_base;
316 dw_addr_t addr_offset = (adjust_opcode / prologue.line_range) * prologue.min_inst_length;
317 log->Printf( "0x%8.8x: DW_LNS_const_add_pc (0x%8.8" PRIx64 ")", op_offset, addr_offset);
318 row.address += addr_offset;
319 }
320 break;
321
322 case DW_LNS_fixed_advance_pc:
323 {
324 uint16_t pc_offset = debug_line_data.GetU16(&offset);
325 log->Printf( "0x%8.8x: DW_LNS_fixed_advance_pc (0x%4.4x)", op_offset, pc_offset);
326 row.address += pc_offset;
327 }
328 break;
329
330 case DW_LNS_set_prologue_end:
331 row.prologue_end = true;
332 log->Printf( "0x%8.8x: DW_LNS_set_prologue_end", op_offset);
333 break;
334
335 case DW_LNS_set_epilogue_begin:
336 row.epilogue_begin = true;
337 log->Printf( "0x%8.8x: DW_LNS_set_epilogue_begin", op_offset);
338 break;
339
340 case DW_LNS_set_isa:
341 row.isa = debug_line_data.GetULEB128(&offset);
342 log->Printf( "0x%8.8x: DW_LNS_set_isa (%u)", op_offset, row.isa);
343 break;
344
345 // Special Opcodes
346 default:
347 if (opcode < prologue.opcode_base)
348 {
349 // We have an opcode that this parser doesn't know about, skip
350 // the number of ULEB128 numbers that is says to skip in the
351 // prologue's standard_opcode_lengths array
352 uint8_t n = prologue.standard_opcode_lengths[opcode-1];
353 log->Printf( "0x%8.8x: Special : Unknown skipping %u ULEB128 values.", op_offset, n);
354 while (n > 0)
355 {
356 debug_line_data.GetULEB128(&offset);
357 --n;
358 }
359 }
360 else
361 {
362 uint8_t adjust_opcode = opcode - prologue.opcode_base;
363 dw_addr_t addr_offset = (adjust_opcode / prologue.line_range) * prologue.min_inst_length;
364 int32_t line_offset = prologue.line_base + (adjust_opcode % prologue.line_range);
365 log->Printf("0x%8.8x: address += 0x%" PRIx64 ", line += %i\n", op_offset, (uint64_t)addr_offset, line_offset);
366 row.address += addr_offset;
367 row.line += line_offset;
368 row.Dump (log);
369 }
370 break;
371 }
372 }
373 return end_offset;
374 }
375 return DW_INVALID_OFFSET;
376 }
377
378
379
380
381 //----------------------------------------------------------------------
382 // Parse
383 //
384 // Parse the entire line table contents calling callback each time a
385 // new prologue is parsed and every time a new row is to be added to
386 // the line table.
387 //----------------------------------------------------------------------
388 void
Parse(const DataExtractor & debug_line_data,DWARFDebugLine::State::Callback callback,void * userData)389 DWARFDebugLine::Parse(const DataExtractor& debug_line_data, DWARFDebugLine::State::Callback callback, void* userData)
390 {
391 lldb::offset_t offset = 0;
392 if (debug_line_data.ValidOffset(offset))
393 {
394 if (!ParseStatementTable(debug_line_data, &offset, callback, userData))
395 ++offset; // Skip to next byte in .debug_line section
396 }
397 }
398
399
400 //----------------------------------------------------------------------
401 // DWARFDebugLine::ParsePrologue
402 //----------------------------------------------------------------------
403 bool
ParsePrologue(const DataExtractor & debug_line_data,lldb::offset_t * offset_ptr,Prologue * prologue)404 DWARFDebugLine::ParsePrologue(const DataExtractor& debug_line_data, lldb::offset_t* offset_ptr, Prologue* prologue)
405 {
406 const lldb::offset_t prologue_offset = *offset_ptr;
407
408 //DEBUG_PRINTF("0x%8.8x: ParsePrologue()\n", *offset_ptr);
409
410 prologue->Clear();
411 uint32_t i;
412 const char * s;
413 prologue->total_length = debug_line_data.GetU32(offset_ptr);
414 prologue->version = debug_line_data.GetU16(offset_ptr);
415 if (prologue->version != 2)
416 return false;
417
418 prologue->prologue_length = debug_line_data.GetU32(offset_ptr);
419 const lldb::offset_t end_prologue_offset = prologue->prologue_length + *offset_ptr;
420 prologue->min_inst_length = debug_line_data.GetU8(offset_ptr);
421 prologue->default_is_stmt = debug_line_data.GetU8(offset_ptr);
422 prologue->line_base = debug_line_data.GetU8(offset_ptr);
423 prologue->line_range = debug_line_data.GetU8(offset_ptr);
424 prologue->opcode_base = debug_line_data.GetU8(offset_ptr);
425
426 prologue->standard_opcode_lengths.reserve(prologue->opcode_base-1);
427
428 for (i=1; i<prologue->opcode_base; ++i)
429 {
430 uint8_t op_len = debug_line_data.GetU8(offset_ptr);
431 prologue->standard_opcode_lengths.push_back(op_len);
432 }
433
434 while (*offset_ptr < end_prologue_offset)
435 {
436 s = debug_line_data.GetCStr(offset_ptr);
437 if (s && s[0])
438 prologue->include_directories.push_back(s);
439 else
440 break;
441 }
442
443 while (*offset_ptr < end_prologue_offset)
444 {
445 const char* name = debug_line_data.GetCStr( offset_ptr );
446 if (name && name[0])
447 {
448 FileNameEntry fileEntry;
449 fileEntry.name = name;
450 fileEntry.dir_idx = debug_line_data.GetULEB128( offset_ptr );
451 fileEntry.mod_time = debug_line_data.GetULEB128( offset_ptr );
452 fileEntry.length = debug_line_data.GetULEB128( offset_ptr );
453 prologue->file_names.push_back(fileEntry);
454 }
455 else
456 break;
457 }
458
459 if (*offset_ptr != end_prologue_offset)
460 {
461 Host::SystemLog (Host::eSystemLogWarning,
462 "warning: parsing line table prologue at 0x%8.8" PRIx64 " should have ended at 0x%8.8" PRIx64 " but it ended ad 0x%8.8" PRIx64 "\n",
463 prologue_offset,
464 end_prologue_offset,
465 *offset_ptr);
466 }
467 return end_prologue_offset;
468 }
469
470 bool
ParseSupportFiles(const lldb::ModuleSP & module_sp,const DataExtractor & debug_line_data,const char * cu_comp_dir,dw_offset_t stmt_list,FileSpecList & support_files)471 DWARFDebugLine::ParseSupportFiles (const lldb::ModuleSP &module_sp,
472 const DataExtractor& debug_line_data,
473 const char *cu_comp_dir,
474 dw_offset_t stmt_list,
475 FileSpecList &support_files)
476 {
477 lldb::offset_t offset = stmt_list + 4; // Skip the total length
478 const char * s;
479 uint32_t version = debug_line_data.GetU16(&offset);
480 if (version != 2)
481 return false;
482
483 const dw_offset_t end_prologue_offset = debug_line_data.GetU32(&offset) + offset;
484 // Skip instruction length, default is stmt, line base, line range and
485 // opcode base, and all opcode lengths
486 offset += 4;
487 const uint8_t opcode_base = debug_line_data.GetU8(&offset);
488 offset += opcode_base - 1;
489 std::vector<std::string> include_directories;
490 include_directories.push_back(""); // Directory at index zero doesn't exist
491 while (offset < end_prologue_offset)
492 {
493 s = debug_line_data.GetCStr(&offset);
494 if (s && s[0])
495 include_directories.push_back(s);
496 else
497 break;
498 }
499 std::string fullpath;
500 std::string remapped_fullpath;
501 while (offset < end_prologue_offset)
502 {
503 const char* path = debug_line_data.GetCStr( &offset );
504 if (path && path[0])
505 {
506 uint32_t dir_idx = debug_line_data.GetULEB128( &offset );
507 debug_line_data.Skip_LEB128(&offset); // Skip mod_time
508 debug_line_data.Skip_LEB128(&offset); // Skip length
509
510 if (path[0] == '/')
511 {
512 // The path starts with a directory delimiter, so we are done.
513 if (module_sp->RemapSourceFile (path, fullpath))
514 support_files.Append(FileSpec (fullpath.c_str(), false));
515 else
516 support_files.Append(FileSpec (path, false));
517 }
518 else
519 {
520 if (dir_idx > 0 && dir_idx < include_directories.size())
521 {
522 if (cu_comp_dir && include_directories[dir_idx][0] != '/')
523 {
524 fullpath = cu_comp_dir;
525
526 if (*fullpath.rbegin() != '/')
527 fullpath += '/';
528 fullpath += include_directories[dir_idx];
529
530 }
531 else
532 fullpath = include_directories[dir_idx];
533 }
534 else if (cu_comp_dir && cu_comp_dir[0])
535 {
536 fullpath = cu_comp_dir;
537 }
538
539 if (!fullpath.empty())
540 {
541 if (*fullpath.rbegin() != '/')
542 fullpath += '/';
543 }
544 fullpath += path;
545 if (module_sp->RemapSourceFile (fullpath.c_str(), remapped_fullpath))
546 support_files.Append(FileSpec (remapped_fullpath.c_str(), false));
547 else
548 support_files.Append(FileSpec (fullpath.c_str(), false));
549 }
550
551 }
552 }
553
554 if (offset != end_prologue_offset)
555 {
556 Host::SystemLog (Host::eSystemLogError,
557 "warning: parsing line table prologue at 0x%8.8x should have ended at 0x%8.8x but it ended ad 0x%8.8" PRIx64 "\n",
558 stmt_list,
559 end_prologue_offset,
560 offset);
561 }
562 return end_prologue_offset;
563 }
564
565 //----------------------------------------------------------------------
566 // ParseStatementTable
567 //
568 // Parse a single line table (prologue and all rows) and call the
569 // callback function once for the prologue (row in state will be zero)
570 // and each time a row is to be added to the line table.
571 //----------------------------------------------------------------------
572 bool
ParseStatementTable(const DataExtractor & debug_line_data,lldb::offset_t * offset_ptr,DWARFDebugLine::State::Callback callback,void * userData)573 DWARFDebugLine::ParseStatementTable
574 (
575 const DataExtractor& debug_line_data,
576 lldb::offset_t* offset_ptr,
577 DWARFDebugLine::State::Callback callback,
578 void* userData
579 )
580 {
581 Log *log (LogChannelDWARF::GetLogIfAll(DWARF_LOG_DEBUG_LINE));
582 Prologue::shared_ptr prologue(new Prologue());
583
584
585 const dw_offset_t debug_line_offset = *offset_ptr;
586
587 Timer scoped_timer (__PRETTY_FUNCTION__,
588 "DWARFDebugLine::ParseStatementTable (.debug_line[0x%8.8x])",
589 debug_line_offset);
590
591 if (!ParsePrologue(debug_line_data, offset_ptr, prologue.get()))
592 {
593 if (log)
594 log->Error ("failed to parse DWARF line table prologue");
595 // Restore our offset and return false to indicate failure!
596 *offset_ptr = debug_line_offset;
597 return false;
598 }
599
600 if (log)
601 prologue->Dump (log);
602
603 const dw_offset_t end_offset = debug_line_offset + prologue->total_length + sizeof(prologue->total_length);
604
605 State state(prologue, log, callback, userData);
606
607 while (*offset_ptr < end_offset)
608 {
609 //DEBUG_PRINTF("0x%8.8x: ", *offset_ptr);
610 uint8_t opcode = debug_line_data.GetU8(offset_ptr);
611
612 if (opcode == 0)
613 {
614 // Extended Opcodes always start with a zero opcode followed by
615 // a uleb128 length so you can skip ones you don't know about
616 lldb::offset_t ext_offset = *offset_ptr;
617 dw_uleb128_t len = debug_line_data.GetULEB128(offset_ptr);
618 dw_offset_t arg_size = len - (*offset_ptr - ext_offset);
619
620 //DEBUG_PRINTF("Extended: <%2u> ", len);
621 uint8_t sub_opcode = debug_line_data.GetU8(offset_ptr);
622 switch (sub_opcode)
623 {
624 case DW_LNE_end_sequence:
625 // Set the end_sequence register of the state machine to true and
626 // append a row to the matrix using the current values of the
627 // state-machine registers. Then reset the registers to the initial
628 // values specified above. Every statement program sequence must end
629 // with a DW_LNE_end_sequence instruction which creates a row whose
630 // address is that of the byte after the last target machine instruction
631 // of the sequence.
632 state.end_sequence = true;
633 state.AppendRowToMatrix(*offset_ptr);
634 state.Reset();
635 break;
636
637 case DW_LNE_set_address:
638 // Takes a single relocatable address as an operand. The size of the
639 // operand is the size appropriate to hold an address on the target
640 // machine. Set the address register to the value given by the
641 // relocatable address. All of the other statement program opcodes
642 // that affect the address register add a delta to it. This instruction
643 // stores a relocatable value into it instead.
644 state.address = debug_line_data.GetAddress(offset_ptr);
645 break;
646
647 case DW_LNE_define_file:
648 // Takes 4 arguments. The first is a null terminated string containing
649 // a source file name. The second is an unsigned LEB128 number representing
650 // the directory index of the directory in which the file was found. The
651 // third is an unsigned LEB128 number representing the time of last
652 // modification of the file. The fourth is an unsigned LEB128 number
653 // representing the length in bytes of the file. The time and length
654 // fields may contain LEB128(0) if the information is not available.
655 //
656 // The directory index represents an entry in the include_directories
657 // section of the statement program prologue. The index is LEB128(0)
658 // if the file was found in the current directory of the compilation,
659 // LEB128(1) if it was found in the first directory in the
660 // include_directories section, and so on. The directory index is
661 // ignored for file names that represent full path names.
662 //
663 // The files are numbered, starting at 1, in the order in which they
664 // appear; the names in the prologue come before names defined by
665 // the DW_LNE_define_file instruction. These numbers are used in the
666 // the file register of the state machine.
667 {
668 FileNameEntry fileEntry;
669 fileEntry.name = debug_line_data.GetCStr(offset_ptr);
670 fileEntry.dir_idx = debug_line_data.GetULEB128(offset_ptr);
671 fileEntry.mod_time = debug_line_data.GetULEB128(offset_ptr);
672 fileEntry.length = debug_line_data.GetULEB128(offset_ptr);
673 state.prologue->file_names.push_back(fileEntry);
674 }
675 break;
676
677 default:
678 // Length doesn't include the zero opcode byte or the length itself, but
679 // it does include the sub_opcode, so we have to adjust for that below
680 (*offset_ptr) += arg_size;
681 break;
682 }
683 }
684 else if (opcode < prologue->opcode_base)
685 {
686 switch (opcode)
687 {
688 // Standard Opcodes
689 case DW_LNS_copy:
690 // Takes no arguments. Append a row to the matrix using the
691 // current values of the state-machine registers. Then set
692 // the basic_block register to false.
693 state.AppendRowToMatrix(*offset_ptr);
694 break;
695
696 case DW_LNS_advance_pc:
697 // Takes a single unsigned LEB128 operand, multiplies it by the
698 // min_inst_length field of the prologue, and adds the
699 // result to the address register of the state machine.
700 state.address += debug_line_data.GetULEB128(offset_ptr) * prologue->min_inst_length;
701 break;
702
703 case DW_LNS_advance_line:
704 // Takes a single signed LEB128 operand and adds that value to
705 // the line register of the state machine.
706 state.line += debug_line_data.GetSLEB128(offset_ptr);
707 break;
708
709 case DW_LNS_set_file:
710 // Takes a single unsigned LEB128 operand and stores it in the file
711 // register of the state machine.
712 state.file = debug_line_data.GetULEB128(offset_ptr);
713 break;
714
715 case DW_LNS_set_column:
716 // Takes a single unsigned LEB128 operand and stores it in the
717 // column register of the state machine.
718 state.column = debug_line_data.GetULEB128(offset_ptr);
719 break;
720
721 case DW_LNS_negate_stmt:
722 // Takes no arguments. Set the is_stmt register of the state
723 // machine to the logical negation of its current value.
724 state.is_stmt = !state.is_stmt;
725 break;
726
727 case DW_LNS_set_basic_block:
728 // Takes no arguments. Set the basic_block register of the
729 // state machine to true
730 state.basic_block = true;
731 break;
732
733 case DW_LNS_const_add_pc:
734 // Takes no arguments. Add to the address register of the state
735 // machine the address increment value corresponding to special
736 // opcode 255. The motivation for DW_LNS_const_add_pc is this:
737 // when the statement program needs to advance the address by a
738 // small amount, it can use a single special opcode, which occupies
739 // a single byte. When it needs to advance the address by up to
740 // twice the range of the last special opcode, it can use
741 // DW_LNS_const_add_pc followed by a special opcode, for a total
742 // of two bytes. Only if it needs to advance the address by more
743 // than twice that range will it need to use both DW_LNS_advance_pc
744 // and a special opcode, requiring three or more bytes.
745 {
746 uint8_t adjust_opcode = 255 - prologue->opcode_base;
747 dw_addr_t addr_offset = (adjust_opcode / prologue->line_range) * prologue->min_inst_length;
748 state.address += addr_offset;
749 }
750 break;
751
752 case DW_LNS_fixed_advance_pc:
753 // Takes a single uhalf operand. Add to the address register of
754 // the state machine the value of the (unencoded) operand. This
755 // is the only extended opcode that takes an argument that is not
756 // a variable length number. The motivation for DW_LNS_fixed_advance_pc
757 // is this: existing assemblers cannot emit DW_LNS_advance_pc or
758 // special opcodes because they cannot encode LEB128 numbers or
759 // judge when the computation of a special opcode overflows and
760 // requires the use of DW_LNS_advance_pc. Such assemblers, however,
761 // can use DW_LNS_fixed_advance_pc instead, sacrificing compression.
762 state.address += debug_line_data.GetU16(offset_ptr);
763 break;
764
765 case DW_LNS_set_prologue_end:
766 // Takes no arguments. Set the prologue_end register of the
767 // state machine to true
768 state.prologue_end = true;
769 break;
770
771 case DW_LNS_set_epilogue_begin:
772 // Takes no arguments. Set the basic_block register of the
773 // state machine to true
774 state.epilogue_begin = true;
775 break;
776
777 case DW_LNS_set_isa:
778 // Takes a single unsigned LEB128 operand and stores it in the
779 // column register of the state machine.
780 state.isa = debug_line_data.GetULEB128(offset_ptr);
781 break;
782
783 default:
784 // Handle any unknown standard opcodes here. We know the lengths
785 // of such opcodes because they are specified in the prologue
786 // as a multiple of LEB128 operands for each opcode.
787 {
788 uint8_t i;
789 assert (opcode - 1 < prologue->standard_opcode_lengths.size());
790 const uint8_t opcode_length = prologue->standard_opcode_lengths[opcode - 1];
791 for (i=0; i<opcode_length; ++i)
792 debug_line_data.Skip_LEB128(offset_ptr);
793 }
794 break;
795 }
796 }
797 else
798 {
799 // Special Opcodes
800
801 // A special opcode value is chosen based on the amount that needs
802 // to be added to the line and address registers. The maximum line
803 // increment for a special opcode is the value of the line_base
804 // field in the header, plus the value of the line_range field,
805 // minus 1 (line base + line range - 1). If the desired line
806 // increment is greater than the maximum line increment, a standard
807 // opcode must be used instead of a special opcode. The "address
808 // advance" is calculated by dividing the desired address increment
809 // by the minimum_instruction_length field from the header. The
810 // special opcode is then calculated using the following formula:
811 //
812 // opcode = (desired line increment - line_base) + (line_range * address advance) + opcode_base
813 //
814 // If the resulting opcode is greater than 255, a standard opcode
815 // must be used instead.
816 //
817 // To decode a special opcode, subtract the opcode_base from the
818 // opcode itself to give the adjusted opcode. The amount to
819 // increment the address register is the result of the adjusted
820 // opcode divided by the line_range multiplied by the
821 // minimum_instruction_length field from the header. That is:
822 //
823 // address increment = (adjusted opcode / line_range) * minimum_instruction_length
824 //
825 // The amount to increment the line register is the line_base plus
826 // the result of the adjusted opcode modulo the line_range. That is:
827 //
828 // line increment = line_base + (adjusted opcode % line_range)
829
830 uint8_t adjust_opcode = opcode - prologue->opcode_base;
831 dw_addr_t addr_offset = (adjust_opcode / prologue->line_range) * prologue->min_inst_length;
832 int32_t line_offset = prologue->line_base + (adjust_opcode % prologue->line_range);
833 state.line += line_offset;
834 state.address += addr_offset;
835 state.AppendRowToMatrix(*offset_ptr);
836 }
837 }
838
839 state.Finalize( *offset_ptr );
840
841 return end_offset;
842 }
843
844
845 //----------------------------------------------------------------------
846 // ParseStatementTableCallback
847 //----------------------------------------------------------------------
848 static void
ParseStatementTableCallback(dw_offset_t offset,const DWARFDebugLine::State & state,void * userData)849 ParseStatementTableCallback(dw_offset_t offset, const DWARFDebugLine::State& state, void* userData)
850 {
851 DWARFDebugLine::LineTable* line_table = (DWARFDebugLine::LineTable*)userData;
852 if (state.row == DWARFDebugLine::State::StartParsingLineTable)
853 {
854 // Just started parsing the line table, so lets keep a reference to
855 // the prologue using the supplied shared pointer
856 line_table->prologue = state.prologue;
857 }
858 else if (state.row == DWARFDebugLine::State::DoneParsingLineTable)
859 {
860 // Done parsing line table, nothing to do for the cleanup
861 }
862 else
863 {
864 // We have a new row, lets append it
865 line_table->AppendRow(state);
866 }
867 }
868
869 //----------------------------------------------------------------------
870 // ParseStatementTable
871 //
872 // Parse a line table at offset and populate the LineTable class with
873 // the prologue and all rows.
874 //----------------------------------------------------------------------
875 bool
ParseStatementTable(const DataExtractor & debug_line_data,lldb::offset_t * offset_ptr,LineTable * line_table)876 DWARFDebugLine::ParseStatementTable(const DataExtractor& debug_line_data, lldb::offset_t *offset_ptr, LineTable* line_table)
877 {
878 return ParseStatementTable(debug_line_data, offset_ptr, ParseStatementTableCallback, line_table);
879 }
880
881
882 inline bool
IsValid() const883 DWARFDebugLine::Prologue::IsValid() const
884 {
885 return SymbolFileDWARF::SupportedVersion(version);
886 }
887
888 //----------------------------------------------------------------------
889 // DWARFDebugLine::Prologue::Dump
890 //----------------------------------------------------------------------
891 void
Dump(Log * log)892 DWARFDebugLine::Prologue::Dump(Log *log)
893 {
894 uint32_t i;
895
896 log->Printf( "Line table prologue:");
897 log->Printf( " total_length: 0x%8.8x", total_length);
898 log->Printf( " version: %u", version);
899 log->Printf( "prologue_length: 0x%8.8x", prologue_length);
900 log->Printf( "min_inst_length: %u", min_inst_length);
901 log->Printf( "default_is_stmt: %u", default_is_stmt);
902 log->Printf( " line_base: %i", line_base);
903 log->Printf( " line_range: %u", line_range);
904 log->Printf( " opcode_base: %u", opcode_base);
905
906 for (i=0; i<standard_opcode_lengths.size(); ++i)
907 {
908 log->Printf( "standard_opcode_lengths[%s] = %u", DW_LNS_value_to_name(i+1), standard_opcode_lengths[i]);
909 }
910
911 if (!include_directories.empty())
912 {
913 for (i=0; i<include_directories.size(); ++i)
914 {
915 log->Printf( "include_directories[%3u] = '%s'", i+1, include_directories[i].c_str());
916 }
917 }
918
919 if (!file_names.empty())
920 {
921 log->PutCString (" Dir Mod Time File Len File Name");
922 log->PutCString (" ---- ---------- ---------- ---------------------------");
923 for (i=0; i<file_names.size(); ++i)
924 {
925 const FileNameEntry& fileEntry = file_names[i];
926 log->Printf ("file_names[%3u] %4u 0x%8.8x 0x%8.8x %s",
927 i+1,
928 fileEntry.dir_idx,
929 fileEntry.mod_time,
930 fileEntry.length,
931 fileEntry.name.c_str());
932 }
933 }
934 }
935
936
937 //----------------------------------------------------------------------
938 // DWARFDebugLine::ParsePrologue::Append
939 //
940 // Append the contents of the prologue to the binary stream buffer
941 //----------------------------------------------------------------------
942 //void
943 //DWARFDebugLine::Prologue::Append(BinaryStreamBuf& buff) const
944 //{
945 // uint32_t i;
946 //
947 // buff.Append32(total_length);
948 // buff.Append16(version);
949 // buff.Append32(prologue_length);
950 // buff.Append8(min_inst_length);
951 // buff.Append8(default_is_stmt);
952 // buff.Append8(line_base);
953 // buff.Append8(line_range);
954 // buff.Append8(opcode_base);
955 //
956 // for (i=0; i<standard_opcode_lengths.size(); ++i)
957 // buff.Append8(standard_opcode_lengths[i]);
958 //
959 // for (i=0; i<include_directories.size(); ++i)
960 // buff.AppendCStr(include_directories[i].c_str());
961 // buff.Append8(0); // Terminate the include directory section with empty string
962 //
963 // for (i=0; i<file_names.size(); ++i)
964 // {
965 // buff.AppendCStr(file_names[i].name.c_str());
966 // buff.Append32_as_ULEB128(file_names[i].dir_idx);
967 // buff.Append32_as_ULEB128(file_names[i].mod_time);
968 // buff.Append32_as_ULEB128(file_names[i].length);
969 // }
970 // buff.Append8(0); // Terminate the file names section with empty string
971 //}
972
973
GetFile(uint32_t file_idx,std::string & path,std::string & directory) const974 bool DWARFDebugLine::Prologue::GetFile(uint32_t file_idx, std::string& path, std::string& directory) const
975 {
976 uint32_t idx = file_idx - 1; // File indexes are 1 based...
977 if (idx < file_names.size())
978 {
979 path = file_names[idx].name;
980 uint32_t dir_idx = file_names[idx].dir_idx - 1;
981 if (dir_idx < include_directories.size())
982 directory = include_directories[dir_idx];
983 else
984 directory.clear();
985 return true;
986 }
987 return false;
988 }
989
990 //----------------------------------------------------------------------
991 // DWARFDebugLine::LineTable::Dump
992 //----------------------------------------------------------------------
993 void
Dump(Log * log) const994 DWARFDebugLine::LineTable::Dump(Log *log) const
995 {
996 if (prologue.get())
997 prologue->Dump (log);
998
999 if (!rows.empty())
1000 {
1001 log->PutCString ("Address Line Column File ISA Flags");
1002 log->PutCString ("------------------ ------ ------ ------ --- -------------");
1003 Row::const_iterator pos = rows.begin();
1004 Row::const_iterator end = rows.end();
1005 while (pos != end)
1006 {
1007 (*pos).Dump (log);
1008 ++pos;
1009 }
1010 }
1011 }
1012
1013
1014 void
AppendRow(const DWARFDebugLine::Row & state)1015 DWARFDebugLine::LineTable::AppendRow(const DWARFDebugLine::Row& state)
1016 {
1017 rows.push_back(state);
1018 }
1019
1020
1021
1022 //----------------------------------------------------------------------
1023 // Compare function for the binary search in DWARFDebugLine::LineTable::LookupAddress()
1024 //----------------------------------------------------------------------
FindMatchingAddress(const DWARFDebugLine::Row & row1,const DWARFDebugLine::Row & row2)1025 static bool FindMatchingAddress (const DWARFDebugLine::Row& row1, const DWARFDebugLine::Row& row2)
1026 {
1027 return row1.address < row2.address;
1028 }
1029
1030
1031 //----------------------------------------------------------------------
1032 // DWARFDebugLine::LineTable::LookupAddress
1033 //----------------------------------------------------------------------
1034 uint32_t
LookupAddress(dw_addr_t address,dw_addr_t cu_high_pc) const1035 DWARFDebugLine::LineTable::LookupAddress(dw_addr_t address, dw_addr_t cu_high_pc) const
1036 {
1037 uint32_t index = UINT32_MAX;
1038 if (!rows.empty())
1039 {
1040 // Use the lower_bound algorithm to perform a binary search since we know
1041 // that our line table data is ordered by address.
1042 DWARFDebugLine::Row row;
1043 row.address = address;
1044 Row::const_iterator begin_pos = rows.begin();
1045 Row::const_iterator end_pos = rows.end();
1046 Row::const_iterator pos = lower_bound(begin_pos, end_pos, row, FindMatchingAddress);
1047 if (pos == end_pos)
1048 {
1049 if (address < cu_high_pc)
1050 return rows.size()-1;
1051 }
1052 else
1053 {
1054 // Rely on fact that we are using a std::vector and we can do
1055 // pointer arithmetic to find the row index (which will be one less
1056 // that what we found since it will find the first position after
1057 // the current address) since std::vector iterators are just
1058 // pointers to the container type.
1059 index = pos - begin_pos;
1060 if (pos->address > address)
1061 {
1062 if (index > 0)
1063 --index;
1064 else
1065 index = UINT32_MAX;
1066 }
1067 }
1068 }
1069 return index; // Failed to find address
1070 }
1071
1072
1073 //----------------------------------------------------------------------
1074 // DWARFDebugLine::Row::Row
1075 //----------------------------------------------------------------------
Row(bool default_is_stmt)1076 DWARFDebugLine::Row::Row(bool default_is_stmt) :
1077 address(0),
1078 line(1),
1079 column(0),
1080 file(1),
1081 is_stmt(default_is_stmt),
1082 basic_block(false),
1083 end_sequence(false),
1084 prologue_end(false),
1085 epilogue_begin(false),
1086 isa(0)
1087 {
1088 }
1089
1090 //----------------------------------------------------------------------
1091 // Called after a row is appended to the matrix
1092 //----------------------------------------------------------------------
1093 void
PostAppend()1094 DWARFDebugLine::Row::PostAppend()
1095 {
1096 basic_block = false;
1097 prologue_end = false;
1098 epilogue_begin = false;
1099 }
1100
1101
1102 //----------------------------------------------------------------------
1103 // DWARFDebugLine::Row::Reset
1104 //----------------------------------------------------------------------
1105 void
Reset(bool default_is_stmt)1106 DWARFDebugLine::Row::Reset(bool default_is_stmt)
1107 {
1108 address = 0;
1109 line = 1;
1110 column = 0;
1111 file = 1;
1112 is_stmt = default_is_stmt;
1113 basic_block = false;
1114 end_sequence = false;
1115 prologue_end = false;
1116 epilogue_begin = false;
1117 isa = 0;
1118 }
1119 //----------------------------------------------------------------------
1120 // DWARFDebugLine::Row::Dump
1121 //----------------------------------------------------------------------
1122 void
Dump(Log * log) const1123 DWARFDebugLine::Row::Dump(Log *log) const
1124 {
1125 log->Printf( "0x%16.16" PRIx64 " %6u %6u %6u %3u %s%s%s%s%s",
1126 address,
1127 line,
1128 column,
1129 file,
1130 isa,
1131 is_stmt ? " is_stmt" : "",
1132 basic_block ? " basic_block" : "",
1133 prologue_end ? " prologue_end" : "",
1134 epilogue_begin ? " epilogue_begin" : "",
1135 end_sequence ? " end_sequence" : "");
1136 }
1137
1138 //----------------------------------------------------------------------
1139 // Compare function LineTable structures
1140 //----------------------------------------------------------------------
AddressLessThan(const DWARFDebugLine::Row & a,const DWARFDebugLine::Row & b)1141 static bool AddressLessThan (const DWARFDebugLine::Row& a, const DWARFDebugLine::Row& b)
1142 {
1143 return a.address < b.address;
1144 }
1145
1146
1147
1148 // Insert a row at the correct address if the addresses can be out of
1149 // order which can only happen when we are linking a line table that
1150 // may have had it's contents rearranged.
1151 void
Insert(Row::collection & state_coll,const Row & state)1152 DWARFDebugLine::Row::Insert(Row::collection& state_coll, const Row& state)
1153 {
1154 // If we don't have anything yet, or if the address of the last state in our
1155 // line table is less than the current one, just append the current state
1156 if (state_coll.empty() || AddressLessThan(state_coll.back(), state))
1157 {
1158 state_coll.push_back(state);
1159 }
1160 else
1161 {
1162 // Do a binary search for the correct entry
1163 pair<Row::iterator, Row::iterator> range(equal_range(state_coll.begin(), state_coll.end(), state, AddressLessThan));
1164
1165 // If the addresses are equal, we can safely replace the previous entry
1166 // with the current one if the one it is replacing is an end_sequence entry.
1167 // We currently always place an extra end sequence when ever we exit a valid
1168 // address range for a function in case the functions get rearranged by
1169 // optimizations or by order specifications. These extra end sequences will
1170 // disappear by getting replaced with valid consecutive entries within a
1171 // compile unit if there are no gaps.
1172 if (range.first == range.second)
1173 {
1174 state_coll.insert(range.first, state);
1175 }
1176 else
1177 {
1178 if ((distance(range.first, range.second) == 1) && range.first->end_sequence == true)
1179 {
1180 *range.first = state;
1181 }
1182 else
1183 {
1184 state_coll.insert(range.second, state);
1185 }
1186 }
1187 }
1188 }
1189
1190 void
Dump(Log * log,const Row::collection & state_coll)1191 DWARFDebugLine::Row::Dump(Log *log, const Row::collection& state_coll)
1192 {
1193 std::for_each (state_coll.begin(), state_coll.end(), bind2nd(std::mem_fun_ref(&Row::Dump),log));
1194 }
1195
1196
1197 //----------------------------------------------------------------------
1198 // DWARFDebugLine::State::State
1199 //----------------------------------------------------------------------
State(Prologue::shared_ptr & p,Log * l,DWARFDebugLine::State::Callback cb,void * userData)1200 DWARFDebugLine::State::State(Prologue::shared_ptr& p, Log *l, DWARFDebugLine::State::Callback cb, void* userData) :
1201 Row (p->default_is_stmt),
1202 prologue (p),
1203 log (l),
1204 callback (cb),
1205 callbackUserData (userData),
1206 row (StartParsingLineTable)
1207 {
1208 // Call the callback with the initial row state of zero for the prologue
1209 if (callback)
1210 callback(0, *this, callbackUserData);
1211 }
1212
1213 //----------------------------------------------------------------------
1214 // DWARFDebugLine::State::Reset
1215 //----------------------------------------------------------------------
1216 void
Reset()1217 DWARFDebugLine::State::Reset()
1218 {
1219 Row::Reset(prologue->default_is_stmt);
1220 }
1221
1222 //----------------------------------------------------------------------
1223 // DWARFDebugLine::State::AppendRowToMatrix
1224 //----------------------------------------------------------------------
1225 void
AppendRowToMatrix(dw_offset_t offset)1226 DWARFDebugLine::State::AppendRowToMatrix(dw_offset_t offset)
1227 {
1228 // Each time we are to add an entry into the line table matrix
1229 // call the callback function so that someone can do something with
1230 // the current state of the state machine (like build a line table
1231 // or dump the line table!)
1232 if (log)
1233 {
1234 if (row == 0)
1235 {
1236 log->PutCString ("Address Line Column File ISA Flags");
1237 log->PutCString ("------------------ ------ ------ ------ --- -------------");
1238 }
1239 Dump (log);
1240 }
1241
1242 ++row; // Increase the row number before we call our callback for a real row
1243 if (callback)
1244 callback(offset, *this, callbackUserData);
1245 PostAppend();
1246 }
1247
1248 //----------------------------------------------------------------------
1249 // DWARFDebugLine::State::Finalize
1250 //----------------------------------------------------------------------
1251 void
Finalize(dw_offset_t offset)1252 DWARFDebugLine::State::Finalize(dw_offset_t offset)
1253 {
1254 // Call the callback with a special row state when we are done parsing a
1255 // line table
1256 row = DoneParsingLineTable;
1257 if (callback)
1258 callback(offset, *this, callbackUserData);
1259 }
1260
1261 //void
1262 //DWARFDebugLine::AppendLineTableData
1263 //(
1264 // const DWARFDebugLine::Prologue* prologue,
1265 // const DWARFDebugLine::Row::collection& state_coll,
1266 // const uint32_t addr_size,
1267 // BinaryStreamBuf &debug_line_data
1268 //)
1269 //{
1270 // if (state_coll.empty())
1271 // {
1272 // // We have no entries, just make an empty line table
1273 // debug_line_data.Append8(0);
1274 // debug_line_data.Append8(1);
1275 // debug_line_data.Append8(DW_LNE_end_sequence);
1276 // }
1277 // else
1278 // {
1279 // DWARFDebugLine::Row::const_iterator pos;
1280 // Row::const_iterator end = state_coll.end();
1281 // bool default_is_stmt = prologue->default_is_stmt;
1282 // const DWARFDebugLine::Row reset_state(default_is_stmt);
1283 // const DWARFDebugLine::Row* prev_state = &reset_state;
1284 // const int32_t max_line_increment_for_special_opcode = prologue->MaxLineIncrementForSpecialOpcode();
1285 // for (pos = state_coll.begin(); pos != end; ++pos)
1286 // {
1287 // const DWARFDebugLine::Row& curr_state = *pos;
1288 // int32_t line_increment = 0;
1289 // dw_addr_t addr_offset = curr_state.address - prev_state->address;
1290 // dw_addr_t addr_advance = (addr_offset) / prologue->min_inst_length;
1291 // line_increment = (int32_t)(curr_state.line - prev_state->line);
1292 //
1293 // // If our previous state was the reset state, then let's emit the
1294 // // address to keep GDB's DWARF parser happy. If we don't start each
1295 // // sequence with a DW_LNE_set_address opcode, the line table won't
1296 // // get slid properly in GDB.
1297 //
1298 // if (prev_state == &reset_state)
1299 // {
1300 // debug_line_data.Append8(0); // Extended opcode
1301 // debug_line_data.Append32_as_ULEB128(addr_size + 1); // Length of opcode bytes
1302 // debug_line_data.Append8(DW_LNE_set_address);
1303 // debug_line_data.AppendMax64(curr_state.address, addr_size);
1304 // addr_advance = 0;
1305 // }
1306 //
1307 // if (prev_state->file != curr_state.file)
1308 // {
1309 // debug_line_data.Append8(DW_LNS_set_file);
1310 // debug_line_data.Append32_as_ULEB128(curr_state.file);
1311 // }
1312 //
1313 // if (prev_state->column != curr_state.column)
1314 // {
1315 // debug_line_data.Append8(DW_LNS_set_column);
1316 // debug_line_data.Append32_as_ULEB128(curr_state.column);
1317 // }
1318 //
1319 // // Don't do anything fancy if we are at the end of a sequence
1320 // // as we don't want to push any extra rows since the DW_LNE_end_sequence
1321 // // will push a row itself!
1322 // if (curr_state.end_sequence)
1323 // {
1324 // if (line_increment != 0)
1325 // {
1326 // debug_line_data.Append8(DW_LNS_advance_line);
1327 // debug_line_data.Append32_as_SLEB128(line_increment);
1328 // }
1329 //
1330 // if (addr_advance > 0)
1331 // {
1332 // debug_line_data.Append8(DW_LNS_advance_pc);
1333 // debug_line_data.Append32_as_ULEB128(addr_advance);
1334 // }
1335 //
1336 // // Now push the end sequence on!
1337 // debug_line_data.Append8(0);
1338 // debug_line_data.Append8(1);
1339 // debug_line_data.Append8(DW_LNE_end_sequence);
1340 //
1341 // prev_state = &reset_state;
1342 // }
1343 // else
1344 // {
1345 // if (line_increment || addr_advance)
1346 // {
1347 // if (line_increment > max_line_increment_for_special_opcode)
1348 // {
1349 // debug_line_data.Append8(DW_LNS_advance_line);
1350 // debug_line_data.Append32_as_SLEB128(line_increment);
1351 // line_increment = 0;
1352 // }
1353 //
1354 // uint32_t special_opcode = (line_increment >= prologue->line_base) ? ((line_increment - prologue->line_base) + (prologue->line_range * addr_advance) + prologue->opcode_base) : 256;
1355 // if (special_opcode > 255)
1356 // {
1357 // // Both the address and line won't fit in one special opcode
1358 // // check to see if just the line advance will?
1359 // uint32_t special_opcode_line = ((line_increment >= prologue->line_base) && (line_increment != 0)) ?
1360 // ((line_increment - prologue->line_base) + prologue->opcode_base) : 256;
1361 //
1362 //
1363 // if (special_opcode_line > 255)
1364 // {
1365 // // Nope, the line advance won't fit by itself, check the address increment by itself
1366 // uint32_t special_opcode_addr = addr_advance ?
1367 // ((0 - prologue->line_base) + (prologue->line_range * addr_advance) + prologue->opcode_base) : 256;
1368 //
1369 // if (special_opcode_addr > 255)
1370 // {
1371 // // Neither the address nor the line will fit in a
1372 // // special opcode, we must manually enter both then
1373 // // do a DW_LNS_copy to push a row (special opcode
1374 // // automatically imply a new row is pushed)
1375 // if (line_increment != 0)
1376 // {
1377 // debug_line_data.Append8(DW_LNS_advance_line);
1378 // debug_line_data.Append32_as_SLEB128(line_increment);
1379 // }
1380 //
1381 // if (addr_advance > 0)
1382 // {
1383 // debug_line_data.Append8(DW_LNS_advance_pc);
1384 // debug_line_data.Append32_as_ULEB128(addr_advance);
1385 // }
1386 //
1387 // // Now push a row onto the line table manually
1388 // debug_line_data.Append8(DW_LNS_copy);
1389 //
1390 // }
1391 // else
1392 // {
1393 // // The address increment alone will fit into a special opcode
1394 // // so modify our line change, then issue a special opcode
1395 // // for the address increment and it will push a row into the
1396 // // line table
1397 // if (line_increment != 0)
1398 // {
1399 // debug_line_data.Append8(DW_LNS_advance_line);
1400 // debug_line_data.Append32_as_SLEB128(line_increment);
1401 // }
1402 //
1403 // // Advance of line and address will fit into a single byte special opcode
1404 // // and this will also push a row onto the line table
1405 // debug_line_data.Append8(special_opcode_addr);
1406 // }
1407 // }
1408 // else
1409 // {
1410 // // The line change alone will fit into a special opcode
1411 // // so modify our address increment first, then issue a
1412 // // special opcode for the line change and it will push
1413 // // a row into the line table
1414 // if (addr_advance > 0)
1415 // {
1416 // debug_line_data.Append8(DW_LNS_advance_pc);
1417 // debug_line_data.Append32_as_ULEB128(addr_advance);
1418 // }
1419 //
1420 // // Advance of line and address will fit into a single byte special opcode
1421 // // and this will also push a row onto the line table
1422 // debug_line_data.Append8(special_opcode_line);
1423 // }
1424 // }
1425 // else
1426 // {
1427 // // Advance of line and address will fit into a single byte special opcode
1428 // // and this will also push a row onto the line table
1429 // debug_line_data.Append8(special_opcode);
1430 // }
1431 // }
1432 // prev_state = &curr_state;
1433 // }
1434 // }
1435 // }
1436 //}
1437