1 //===-- DWARFUnit.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 "DWARFUnit.h"
11 
12 #include "lldb/Core/Module.h"
13 #include "lldb/Host/StringConvert.h"
14 #include "lldb/Symbol/CompileUnit.h"
15 #include "lldb/Symbol/LineTable.h"
16 #include "lldb/Symbol/ObjectFile.h"
17 #include "lldb/Utility/LLDBAssert.h"
18 #include "lldb/Utility/StreamString.h"
19 #include "lldb/Utility/Timer.h"
20 
21 #include "DWARFDIECollection.h"
22 #include "DWARFDebugAranges.h"
23 #include "DWARFDebugInfo.h"
24 #include "LogChannelDWARF.h"
25 #include "SymbolFileDWARFDebugMap.h"
26 #include "SymbolFileDWARFDwo.h"
27 
28 using namespace lldb;
29 using namespace lldb_private;
30 using namespace std;
31 
32 extern int g_verbose;
33 
34 DWARFUnit::DWARFUnit(SymbolFileDWARF *dwarf)
35     : m_dwarf(dwarf), m_cancel_scopes(false) {}
36 
37 DWARFUnit::~DWARFUnit() {}
38 
39 //----------------------------------------------------------------------
40 // Parses first DIE of a compile unit.
41 //----------------------------------------------------------------------
42 void DWARFUnit::ExtractUnitDIEIfNeeded() {
43   {
44     llvm::sys::ScopedReader lock(m_first_die_mutex);
45     if (m_first_die)
46       return; // Already parsed
47   }
48   llvm::sys::ScopedWriter lock(m_first_die_mutex);
49   if (m_first_die)
50     return; // Already parsed
51 
52   static Timer::Category func_cat(LLVM_PRETTY_FUNCTION);
53   Timer scoped_timer(
54       func_cat, "%8.8x: DWARFUnit::ExtractUnitDIEIfNeeded()", m_offset);
55 
56   // Set the offset to that of the first DIE and calculate the start of the
57   // next compilation unit header.
58   lldb::offset_t offset = GetFirstDIEOffset();
59 
60   // We are in our compile unit, parse starting at the offset we were told to
61   // parse
62   const DWARFDataExtractor &data = GetData();
63   DWARFFormValue::FixedFormSizes fixed_form_sizes =
64       DWARFFormValue::GetFixedFormSizesForAddressSize(GetAddressByteSize(),
65                                                       IsDWARF64());
66   if (offset < GetNextCompileUnitOffset() &&
67       m_first_die.FastExtract(data, this, fixed_form_sizes, &offset)) {
68     AddUnitDIE(m_first_die);
69     return;
70   }
71 
72   ExtractDIEsEndCheck(offset);
73 }
74 
75 //----------------------------------------------------------------------
76 // Parses a compile unit and indexes its DIEs if it hasn't already been done.
77 // It will leave this compile unit extracted forever.
78 //----------------------------------------------------------------------
79 void DWARFUnit::ExtractDIEsIfNeeded() {
80   m_cancel_scopes = true;
81 
82   {
83     llvm::sys::ScopedReader lock(m_die_array_mutex);
84     if (!m_die_array.empty())
85       return; // Already parsed
86   }
87   llvm::sys::ScopedWriter lock(m_die_array_mutex);
88   if (!m_die_array.empty())
89     return; // Already parsed
90 
91   ExtractDIEsRWLocked();
92 }
93 
94 //----------------------------------------------------------------------
95 // Parses a compile unit and indexes its DIEs if it hasn't already been done.
96 // It will clear this compile unit after returned instance gets out of scope,
97 // no other ScopedExtractDIEs instance is running for this compile unit
98 // and no ExtractDIEsIfNeeded() has been executed during this ScopedExtractDIEs
99 // lifetime.
100 //----------------------------------------------------------------------
101 DWARFUnit::ScopedExtractDIEs DWARFUnit::ExtractDIEsScoped() {
102   ScopedExtractDIEs scoped(this);
103 
104   {
105     llvm::sys::ScopedReader lock(m_die_array_mutex);
106     if (!m_die_array.empty())
107       return scoped; // Already parsed
108   }
109   llvm::sys::ScopedWriter lock(m_die_array_mutex);
110   if (!m_die_array.empty())
111     return scoped; // Already parsed
112 
113   // Otherwise m_die_array would be already populated.
114   lldbassert(!m_cancel_scopes);
115 
116   ExtractDIEsRWLocked();
117   scoped.m_clear_dies = true;
118   return scoped;
119 }
120 
121 DWARFUnit::ScopedExtractDIEs::ScopedExtractDIEs(DWARFUnit *cu) : m_cu(cu) {
122   lldbassert(m_cu);
123   m_cu->m_die_array_scoped_mutex.lock_shared();
124 }
125 
126 DWARFUnit::ScopedExtractDIEs::~ScopedExtractDIEs() {
127   if (!m_cu)
128     return;
129   m_cu->m_die_array_scoped_mutex.unlock_shared();
130   if (!m_clear_dies || m_cu->m_cancel_scopes)
131     return;
132   // Be sure no other ScopedExtractDIEs is running anymore.
133   llvm::sys::ScopedWriter lock_scoped(m_cu->m_die_array_scoped_mutex);
134   llvm::sys::ScopedWriter lock(m_cu->m_die_array_mutex);
135   if (m_cu->m_cancel_scopes)
136     return;
137   m_cu->ClearDIEsRWLocked();
138 }
139 
140 DWARFUnit::ScopedExtractDIEs::ScopedExtractDIEs(ScopedExtractDIEs &&rhs)
141     : m_cu(rhs.m_cu), m_clear_dies(rhs.m_clear_dies) {
142   rhs.m_cu = nullptr;
143 }
144 
145 DWARFUnit::ScopedExtractDIEs &DWARFUnit::ScopedExtractDIEs::operator=(
146     DWARFUnit::ScopedExtractDIEs &&rhs) {
147   m_cu = rhs.m_cu;
148   rhs.m_cu = nullptr;
149   m_clear_dies = rhs.m_clear_dies;
150   return *this;
151 }
152 
153 //----------------------------------------------------------------------
154 // Parses a compile unit and indexes its DIEs, m_die_array_mutex must be
155 // held R/W and m_die_array must be empty.
156 //----------------------------------------------------------------------
157 void DWARFUnit::ExtractDIEsRWLocked() {
158   llvm::sys::ScopedWriter first_die_lock(m_first_die_mutex);
159 
160   static Timer::Category func_cat(LLVM_PRETTY_FUNCTION);
161   Timer scoped_timer(
162       func_cat, "%8.8x: DWARFUnit::ExtractDIEsIfNeeded()", m_offset);
163 
164   // Set the offset to that of the first DIE and calculate the start of the
165   // next compilation unit header.
166   lldb::offset_t offset = GetFirstDIEOffset();
167   lldb::offset_t next_cu_offset = GetNextCompileUnitOffset();
168 
169   DWARFDebugInfoEntry die;
170   // Keep a flat array of the DIE for binary lookup by DIE offset
171   Log *log(
172       LogChannelDWARF::GetLogIfAny(DWARF_LOG_DEBUG_INFO | DWARF_LOG_LOOKUPS));
173   if (log) {
174     m_dwarf->GetObjectFile()->GetModule()->LogMessageVerboseBacktrace(
175         log,
176         "DWARFUnit::ExtractDIEsIfNeeded () for compile unit at "
177         ".debug_info[0x%8.8x]",
178         GetOffset());
179   }
180 
181   uint32_t depth = 0;
182   // We are in our compile unit, parse starting at the offset we were told to
183   // parse
184   const DWARFDataExtractor &data = GetData();
185   std::vector<uint32_t> die_index_stack;
186   die_index_stack.reserve(32);
187   die_index_stack.push_back(0);
188   bool prev_die_had_children = false;
189   DWARFFormValue::FixedFormSizes fixed_form_sizes =
190       DWARFFormValue::GetFixedFormSizesForAddressSize(GetAddressByteSize(),
191                                                       IsDWARF64());
192   while (offset < next_cu_offset &&
193          die.FastExtract(data, this, fixed_form_sizes, &offset)) {
194     //        if (log)
195     //            log->Printf("0x%8.8x: %*.*s%s%s",
196     //                        die.GetOffset(),
197     //                        depth * 2, depth * 2, "",
198     //                        DW_TAG_value_to_name (die.Tag()),
199     //                        die.HasChildren() ? " *" : "");
200 
201     const bool null_die = die.IsNULL();
202     if (depth == 0) {
203       assert(m_die_array.empty() && "Compile unit DIE already added");
204 
205       // The average bytes per DIE entry has been seen to be around 14-20 so
206       // lets pre-reserve half of that since we are now stripping the NULL
207       // tags.
208 
209       // Only reserve the memory if we are adding children of the main
210       // compile unit DIE. The compile unit DIE is always the first entry, so
211       // if our size is 1, then we are adding the first compile unit child
212       // DIE and should reserve the memory.
213       m_die_array.reserve(GetDebugInfoSize() / 24);
214       m_die_array.push_back(die);
215 
216       if (!m_first_die)
217         AddUnitDIE(m_die_array.front());
218     } else {
219       if (null_die) {
220         if (prev_die_had_children) {
221           // This will only happen if a DIE says is has children but all it
222           // contains is a NULL tag. Since we are removing the NULL DIEs from
223           // the list (saves up to 25% in C++ code), we need a way to let the
224           // DIE know that it actually doesn't have children.
225           if (!m_die_array.empty())
226             m_die_array.back().SetEmptyChildren(true);
227         }
228       } else {
229         die.SetParentIndex(m_die_array.size() - die_index_stack[depth - 1]);
230 
231         if (die_index_stack.back())
232           m_die_array[die_index_stack.back()].SetSiblingIndex(
233               m_die_array.size() - die_index_stack.back());
234 
235         // Only push the DIE if it isn't a NULL DIE
236         m_die_array.push_back(die);
237       }
238     }
239 
240     if (null_die) {
241       // NULL DIE.
242       if (!die_index_stack.empty())
243         die_index_stack.pop_back();
244 
245       if (depth > 0)
246         --depth;
247       if (depth == 0)
248         break; // We are done with this compile unit!
249 
250       prev_die_had_children = false;
251     } else {
252       die_index_stack.back() = m_die_array.size() - 1;
253       // Normal DIE
254       const bool die_has_children = die.HasChildren();
255       if (die_has_children) {
256         die_index_stack.push_back(0);
257         ++depth;
258       }
259       prev_die_had_children = die_has_children;
260     }
261   }
262 
263   if (!m_die_array.empty()) {
264     lldbassert(!m_first_die || m_first_die == m_die_array.front());
265     m_first_die = m_die_array.front();
266   }
267 
268   m_die_array.shrink_to_fit();
269 
270   ExtractDIEsEndCheck(offset);
271 
272   if (m_dwo_symbol_file) {
273     DWARFUnit *dwo_cu = m_dwo_symbol_file->GetCompileUnit();
274     dwo_cu->ExtractDIEsIfNeeded();
275   }
276 }
277 
278 //--------------------------------------------------------------------------
279 // Final checks for both ExtractUnitDIEIfNeeded() and ExtractDIEsIfNeeded().
280 //--------------------------------------------------------------------------
281 void DWARFUnit::ExtractDIEsEndCheck(lldb::offset_t offset) const {
282   // Give a little bit of info if we encounter corrupt DWARF (our offset should
283   // always terminate at or before the start of the next compilation unit
284   // header).
285   if (offset > GetNextCompileUnitOffset()) {
286     m_dwarf->GetObjectFile()->GetModule()->ReportWarning(
287         "DWARF compile unit extends beyond its bounds cu 0x%8.8x at "
288         "0x%8.8" PRIx64 "\n",
289         GetOffset(), offset);
290   }
291 
292   Log *log(LogChannelDWARF::GetLogIfAll(DWARF_LOG_DEBUG_INFO));
293   if (log && log->GetVerbose()) {
294     StreamString strm;
295     Dump(&strm);
296     if (m_die_array.empty())
297       strm.Printf("error: no DIE for compile unit");
298     else
299       m_die_array[0].Dump(m_dwarf, this, strm, UINT32_MAX);
300     log->PutString(strm.GetString());
301   }
302 }
303 
304 // m_die_array_mutex must be already held as read/write.
305 void DWARFUnit::AddUnitDIE(const DWARFDebugInfoEntry &cu_die) {
306   uint64_t base_addr = cu_die.GetAttributeValueAsAddress(
307       m_dwarf, this, DW_AT_low_pc, LLDB_INVALID_ADDRESS);
308   if (base_addr == LLDB_INVALID_ADDRESS)
309     base_addr = cu_die.GetAttributeValueAsAddress(
310         m_dwarf, this, DW_AT_entry_pc, 0);
311   SetBaseAddress(base_addr);
312 
313   std::unique_ptr<SymbolFileDWARFDwo> dwo_symbol_file =
314       m_dwarf->GetDwoSymbolFileForCompileUnit(*this, cu_die);
315   if (!dwo_symbol_file)
316     return;
317 
318   DWARFUnit *dwo_cu = dwo_symbol_file->GetCompileUnit();
319   if (!dwo_cu)
320     return; // Can't fetch the compile unit from the dwo file.
321 
322   DWARFBaseDIE dwo_cu_die = dwo_cu->GetUnitDIEOnly();
323   if (!dwo_cu_die.IsValid())
324     return; // Can't fetch the compile unit DIE from the dwo file.
325 
326   uint64_t main_dwo_id =
327       cu_die.GetAttributeValueAsUnsigned(m_dwarf, this, DW_AT_GNU_dwo_id, 0);
328   uint64_t sub_dwo_id =
329       dwo_cu_die.GetAttributeValueAsUnsigned(DW_AT_GNU_dwo_id, 0);
330   if (main_dwo_id != sub_dwo_id)
331     return; // The 2 dwo ID isn't match. Don't use the dwo file as it belongs to
332   // a differectn compilation.
333 
334   m_dwo_symbol_file = std::move(dwo_symbol_file);
335 
336   dw_addr_t addr_base =
337       cu_die.GetAttributeValueAsUnsigned(m_dwarf, this, DW_AT_GNU_addr_base, 0);
338   dw_addr_t ranges_base = cu_die.GetAttributeValueAsUnsigned(
339       m_dwarf, this, DW_AT_GNU_ranges_base, 0);
340   dwo_cu->SetAddrBase(addr_base, ranges_base, m_offset);
341 }
342 
343 DWARFDIE DWARFUnit::LookupAddress(const dw_addr_t address) {
344   if (DIE()) {
345     const DWARFDebugAranges &func_aranges = GetFunctionAranges();
346 
347     // Re-check the aranges auto pointer contents in case it was created above
348     if (!func_aranges.IsEmpty())
349       return GetDIE(func_aranges.FindAddress(address));
350   }
351   return DWARFDIE();
352 }
353 
354 size_t DWARFUnit::AppendDIEsWithTag(const dw_tag_t tag,
355 				    DWARFDIECollection &dies,
356 				    uint32_t depth) const {
357   size_t old_size = dies.Size();
358   {
359     llvm::sys::ScopedReader lock(m_die_array_mutex);
360     DWARFDebugInfoEntry::const_iterator pos;
361     DWARFDebugInfoEntry::const_iterator end = m_die_array.end();
362     for (pos = m_die_array.begin(); pos != end; ++pos) {
363       if (pos->Tag() == tag)
364         dies.Append(DWARFDIE(this, &(*pos)));
365     }
366   }
367 
368   // Return the number of DIEs added to the collection
369   return dies.Size() - old_size;
370 }
371 
372 
373 lldb::user_id_t DWARFUnit::GetID() const {
374   dw_offset_t local_id =
375       m_base_obj_offset != DW_INVALID_OFFSET ? m_base_obj_offset : m_offset;
376   if (m_dwarf)
377     return DIERef(local_id, local_id).GetUID(m_dwarf);
378   else
379     return local_id;
380 }
381 
382 dw_offset_t DWARFUnit::GetNextCompileUnitOffset() const {
383   return m_offset + GetLengthByteSize() + GetLength();
384 }
385 
386 size_t DWARFUnit::GetDebugInfoSize() const {
387   return GetLengthByteSize() + GetLength() - GetHeaderByteSize();
388 }
389 
390 const DWARFAbbreviationDeclarationSet *DWARFUnit::GetAbbreviations() const {
391   return m_abbrevs;
392 }
393 
394 dw_offset_t DWARFUnit::GetAbbrevOffset() const {
395   return m_abbrevs ? m_abbrevs->GetOffset() : DW_INVALID_OFFSET;
396 }
397 
398 void DWARFUnit::SetAddrBase(dw_addr_t addr_base,
399                             dw_addr_t ranges_base,
400                             dw_offset_t base_obj_offset) {
401   m_addr_base = addr_base;
402   m_ranges_base = ranges_base;
403   m_base_obj_offset = base_obj_offset;
404 }
405 
406 // It may be called only with m_die_array_mutex held R/W.
407 void DWARFUnit::ClearDIEsRWLocked() {
408   m_die_array.clear();
409   m_die_array.shrink_to_fit();
410 
411   if (m_dwo_symbol_file)
412     m_dwo_symbol_file->GetCompileUnit()->ClearDIEsRWLocked();
413 }
414 
415 void DWARFUnit::BuildAddressRangeTable(SymbolFileDWARF *dwarf,
416                                        DWARFDebugAranges *debug_aranges) {
417   // This function is usually called if there in no .debug_aranges section in
418   // order to produce a compile unit level set of address ranges that is
419   // accurate.
420 
421   size_t num_debug_aranges = debug_aranges->GetNumRanges();
422 
423   // First get the compile unit DIE only and check if it has a DW_AT_ranges
424   const DWARFDebugInfoEntry *die = GetUnitDIEPtrOnly();
425 
426   const dw_offset_t cu_offset = GetOffset();
427   if (die) {
428     DWARFRangeList ranges;
429     const size_t num_ranges =
430         die->GetAttributeAddressRanges(dwarf, this, ranges, false);
431     if (num_ranges > 0) {
432       // This compile unit has DW_AT_ranges, assume this is correct if it is
433       // present since clang no longer makes .debug_aranges by default and it
434       // emits DW_AT_ranges for DW_TAG_compile_units. GCC also does this with
435       // recent GCC builds.
436       for (size_t i = 0; i < num_ranges; ++i) {
437         const DWARFRangeList::Entry &range = ranges.GetEntryRef(i);
438         debug_aranges->AppendRange(cu_offset, range.GetRangeBase(),
439                                    range.GetRangeEnd());
440       }
441 
442       return; // We got all of our ranges from the DW_AT_ranges attribute
443     }
444   }
445   // We don't have a DW_AT_ranges attribute, so we need to parse the DWARF
446 
447   // If the DIEs weren't parsed, then we don't want all dies for all compile
448   // units to stay loaded when they weren't needed. So we can end up parsing
449   // the DWARF and then throwing them all away to keep memory usage down.
450   ScopedExtractDIEs clear_dies(ExtractDIEsScoped());
451 
452   die = DIEPtr();
453   if (die)
454     die->BuildAddressRangeTable(dwarf, this, debug_aranges);
455 
456   if (debug_aranges->GetNumRanges() == num_debug_aranges) {
457     // We got nothing from the functions, maybe we have a line tables only
458     // situation. Check the line tables and build the arange table from this.
459     SymbolContext sc;
460     sc.comp_unit = dwarf->GetCompUnitForDWARFCompUnit(this);
461     if (sc.comp_unit) {
462       SymbolFileDWARFDebugMap *debug_map_sym_file =
463           m_dwarf->GetDebugMapSymfile();
464       if (debug_map_sym_file == NULL) {
465         LineTable *line_table = sc.comp_unit->GetLineTable();
466 
467         if (line_table) {
468           LineTable::FileAddressRanges file_ranges;
469           const bool append = true;
470           const size_t num_ranges =
471               line_table->GetContiguousFileAddressRanges(file_ranges, append);
472           for (uint32_t idx = 0; idx < num_ranges; ++idx) {
473             const LineTable::FileAddressRanges::Entry &range =
474                 file_ranges.GetEntryRef(idx);
475             debug_aranges->AppendRange(cu_offset, range.GetRangeBase(),
476                                        range.GetRangeEnd());
477           }
478         }
479       } else
480         debug_map_sym_file->AddOSOARanges(dwarf, debug_aranges);
481     }
482   }
483 
484   if (debug_aranges->GetNumRanges() == num_debug_aranges) {
485     // We got nothing from the functions, maybe we have a line tables only
486     // situation. Check the line tables and build the arange table from this.
487     SymbolContext sc;
488     sc.comp_unit = dwarf->GetCompUnitForDWARFCompUnit(this);
489     if (sc.comp_unit) {
490       LineTable *line_table = sc.comp_unit->GetLineTable();
491 
492       if (line_table) {
493         LineTable::FileAddressRanges file_ranges;
494         const bool append = true;
495         const size_t num_ranges =
496             line_table->GetContiguousFileAddressRanges(file_ranges, append);
497         for (uint32_t idx = 0; idx < num_ranges; ++idx) {
498           const LineTable::FileAddressRanges::Entry &range =
499               file_ranges.GetEntryRef(idx);
500           debug_aranges->AppendRange(GetOffset(), range.GetRangeBase(),
501                                      range.GetRangeEnd());
502         }
503       }
504     }
505   }
506 }
507 
508 lldb::ByteOrder DWARFUnit::GetByteOrder() const {
509   return m_dwarf->GetObjectFile()->GetByteOrder();
510 }
511 
512 TypeSystem *DWARFUnit::GetTypeSystem() {
513   if (m_dwarf)
514     return m_dwarf->GetTypeSystemForLanguage(GetLanguageType());
515   else
516     return nullptr;
517 }
518 
519 DWARFFormValue::FixedFormSizes DWARFUnit::GetFixedFormSizes() {
520   return DWARFFormValue::GetFixedFormSizesForAddressSize(GetAddressByteSize(),
521                                                          IsDWARF64());
522 }
523 
524 void DWARFUnit::SetBaseAddress(dw_addr_t base_addr) { m_base_addr = base_addr; }
525 
526 //----------------------------------------------------------------------
527 // Compare function DWARFDebugAranges::Range structures
528 //----------------------------------------------------------------------
529 static bool CompareDIEOffset(const DWARFDebugInfoEntry &die,
530                              const dw_offset_t die_offset) {
531   return die.GetOffset() < die_offset;
532 }
533 
534 //----------------------------------------------------------------------
535 // GetDIE()
536 //
537 // Get the DIE (Debug Information Entry) with the specified offset by first
538 // checking if the DIE is contained within this compile unit and grabbing the
539 // DIE from this compile unit. Otherwise we grab the DIE from the DWARF file.
540 //----------------------------------------------------------------------
541 DWARFDIE
542 DWARFUnit::GetDIE(dw_offset_t die_offset) {
543   if (die_offset != DW_INVALID_OFFSET) {
544     if (GetDwoSymbolFile())
545       return GetDwoSymbolFile()->GetCompileUnit()->GetDIE(die_offset);
546 
547     if (ContainsDIEOffset(die_offset)) {
548       ExtractDIEsIfNeeded();
549       DWARFDebugInfoEntry::const_iterator end = m_die_array.cend();
550       DWARFDebugInfoEntry::const_iterator pos =
551           lower_bound(m_die_array.cbegin(), end, die_offset, CompareDIEOffset);
552       if (pos != end) {
553         if (die_offset == (*pos).GetOffset())
554           return DWARFDIE(this, &(*pos));
555       }
556     } else {
557       // Don't specify the compile unit offset as we don't know it because the
558       // DIE belongs to
559       // a different compile unit in the same symbol file.
560       return m_dwarf->DebugInfo()->GetDIEForDIEOffset(die_offset);
561     }
562   }
563   return DWARFDIE(); // Not found
564 }
565 
566 uint8_t DWARFUnit::GetAddressByteSize(const DWARFUnit *cu) {
567   if (cu)
568     return cu->GetAddressByteSize();
569   return DWARFUnit::GetDefaultAddressSize();
570 }
571 
572 bool DWARFUnit::IsDWARF64(const DWARFUnit *cu) {
573   if (cu)
574     return cu->IsDWARF64();
575   return false;
576 }
577 
578 uint8_t DWARFUnit::GetDefaultAddressSize() { return 4; }
579 
580 void *DWARFUnit::GetUserData() const { return m_user_data; }
581 
582 void DWARFUnit::SetUserData(void *d) {
583   m_user_data = d;
584   if (m_dwo_symbol_file)
585     m_dwo_symbol_file->GetCompileUnit()->SetUserData(d);
586 }
587 
588 bool DWARFUnit::Supports_DW_AT_APPLE_objc_complete_type() {
589   if (GetProducer() == eProducerLLVMGCC)
590     return false;
591   return true;
592 }
593 
594 bool DWARFUnit::DW_AT_decl_file_attributes_are_invalid() {
595   // llvm-gcc makes completely invalid decl file attributes and won't ever be
596   // fixed, so we need to know to ignore these.
597   return GetProducer() == eProducerLLVMGCC;
598 }
599 
600 bool DWARFUnit::Supports_unnamed_objc_bitfields() {
601   if (GetProducer() == eProducerClang) {
602     const uint32_t major_version = GetProducerVersionMajor();
603     if (major_version > 425 ||
604         (major_version == 425 && GetProducerVersionUpdate() >= 13))
605       return true;
606     else
607       return false;
608   }
609   return true; // Assume all other compilers didn't have incorrect ObjC bitfield
610                // info
611 }
612 
613 SymbolFileDWARF *DWARFUnit::GetSymbolFileDWARF() const { return m_dwarf; }
614 
615 void DWARFUnit::ParseProducerInfo() {
616   m_producer_version_major = UINT32_MAX;
617   m_producer_version_minor = UINT32_MAX;
618   m_producer_version_update = UINT32_MAX;
619 
620   const DWARFDebugInfoEntry *die = GetUnitDIEPtrOnly();
621   if (die) {
622 
623     const char *producer_cstr =
624         die->GetAttributeValueAsString(m_dwarf, this, DW_AT_producer, NULL);
625     if (producer_cstr) {
626       RegularExpression llvm_gcc_regex(
627           llvm::StringRef("^4\\.[012]\\.[01] \\(Based on Apple "
628                           "Inc\\. build [0-9]+\\) \\(LLVM build "
629                           "[\\.0-9]+\\)$"));
630       if (llvm_gcc_regex.Execute(llvm::StringRef(producer_cstr))) {
631         m_producer = eProducerLLVMGCC;
632       } else if (strstr(producer_cstr, "clang")) {
633         static RegularExpression g_clang_version_regex(
634             llvm::StringRef("clang-([0-9]+)\\.([0-9]+)\\.([0-9]+)"));
635         RegularExpression::Match regex_match(3);
636         if (g_clang_version_regex.Execute(llvm::StringRef(producer_cstr),
637                                           &regex_match)) {
638           std::string str;
639           if (regex_match.GetMatchAtIndex(producer_cstr, 1, str))
640             m_producer_version_major =
641                 StringConvert::ToUInt32(str.c_str(), UINT32_MAX, 10);
642           if (regex_match.GetMatchAtIndex(producer_cstr, 2, str))
643             m_producer_version_minor =
644                 StringConvert::ToUInt32(str.c_str(), UINT32_MAX, 10);
645           if (regex_match.GetMatchAtIndex(producer_cstr, 3, str))
646             m_producer_version_update =
647                 StringConvert::ToUInt32(str.c_str(), UINT32_MAX, 10);
648         }
649         m_producer = eProducerClang;
650       } else if (strstr(producer_cstr, "GNU"))
651         m_producer = eProducerGCC;
652     }
653   }
654   if (m_producer == eProducerInvalid)
655     m_producer = eProcucerOther;
656 }
657 
658 DWARFProducer DWARFUnit::GetProducer() {
659   if (m_producer == eProducerInvalid)
660     ParseProducerInfo();
661   return m_producer;
662 }
663 
664 uint32_t DWARFUnit::GetProducerVersionMajor() {
665   if (m_producer_version_major == 0)
666     ParseProducerInfo();
667   return m_producer_version_major;
668 }
669 
670 uint32_t DWARFUnit::GetProducerVersionMinor() {
671   if (m_producer_version_minor == 0)
672     ParseProducerInfo();
673   return m_producer_version_minor;
674 }
675 
676 uint32_t DWARFUnit::GetProducerVersionUpdate() {
677   if (m_producer_version_update == 0)
678     ParseProducerInfo();
679   return m_producer_version_update;
680 }
681 LanguageType DWARFUnit::LanguageTypeFromDWARF(uint64_t val) {
682   // Note: user languages between lo_user and hi_user must be handled
683   // explicitly here.
684   switch (val) {
685   case DW_LANG_Mips_Assembler:
686     return eLanguageTypeMipsAssembler;
687   case DW_LANG_GOOGLE_RenderScript:
688     return eLanguageTypeExtRenderScript;
689   default:
690     return static_cast<LanguageType>(val);
691   }
692 }
693 
694 LanguageType DWARFUnit::GetLanguageType() {
695   if (m_language_type != eLanguageTypeUnknown)
696     return m_language_type;
697 
698   const DWARFDebugInfoEntry *die = GetUnitDIEPtrOnly();
699   if (die)
700     m_language_type = LanguageTypeFromDWARF(
701         die->GetAttributeValueAsUnsigned(m_dwarf, this, DW_AT_language, 0));
702   return m_language_type;
703 }
704 
705 bool DWARFUnit::GetIsOptimized() {
706   if (m_is_optimized == eLazyBoolCalculate) {
707     const DWARFDebugInfoEntry *die = GetUnitDIEPtrOnly();
708     if (die) {
709       m_is_optimized = eLazyBoolNo;
710       if (die->GetAttributeValueAsUnsigned(m_dwarf, this, DW_AT_APPLE_optimized,
711                                            0) == 1) {
712         m_is_optimized = eLazyBoolYes;
713       }
714     }
715   }
716   return m_is_optimized == eLazyBoolYes;
717 }
718 
719 SymbolFileDWARFDwo *DWARFUnit::GetDwoSymbolFile() const {
720   return m_dwo_symbol_file.get();
721 }
722 
723 dw_offset_t DWARFUnit::GetBaseObjOffset() const { return m_base_obj_offset; }
724 
725 const DWARFDebugAranges &DWARFUnit::GetFunctionAranges() {
726   if (m_func_aranges_ap.get() == NULL) {
727     m_func_aranges_ap.reset(new DWARFDebugAranges());
728     Log *log(LogChannelDWARF::GetLogIfAll(DWARF_LOG_DEBUG_ARANGES));
729 
730     if (log) {
731       m_dwarf->GetObjectFile()->GetModule()->LogMessage(
732           log,
733           "DWARFUnit::GetFunctionAranges() for compile unit at "
734           ".debug_info[0x%8.8x]",
735           GetOffset());
736     }
737     const DWARFDebugInfoEntry *die = DIEPtr();
738     if (die)
739       die->BuildFunctionAddressRangeTable(m_dwarf, this,
740                                           m_func_aranges_ap.get());
741 
742     if (m_dwo_symbol_file) {
743       DWARFUnit *dwo_cu = m_dwo_symbol_file->GetCompileUnit();
744       const DWARFDebugInfoEntry *dwo_die = dwo_cu->DIEPtr();
745       if (dwo_die)
746         dwo_die->BuildFunctionAddressRangeTable(m_dwo_symbol_file.get(), dwo_cu,
747                                                 m_func_aranges_ap.get());
748     }
749 
750     const bool minimize = false;
751     m_func_aranges_ap->Sort(minimize);
752   }
753   return *m_func_aranges_ap.get();
754 }
755 
756