1 //===-- Function.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/Symbol/Function.h"
11 #include "lldb/Core/Disassembler.h"
12 #include "lldb/Core/Module.h"
13 #include "lldb/Core/Section.h"
14 #include "lldb/Host/Host.h"
15 #include "lldb/Symbol/CompileUnit.h"
16 #include "lldb/Symbol/CompilerType.h"
17 #include "lldb/Symbol/LineTable.h"
18 #include "lldb/Symbol/SymbolFile.h"
19 #include "lldb/Symbol/SymbolVendor.h"
20 #include "lldb/Target/Language.h"
21 #include "llvm/Support/Casting.h"
22 
23 using namespace lldb;
24 using namespace lldb_private;
25 
26 //----------------------------------------------------------------------
27 // Basic function information is contained in the FunctionInfo class.
28 // It is designed to contain the name, linkage name, and declaration
29 // location.
30 //----------------------------------------------------------------------
31 FunctionInfo::FunctionInfo(const char *name, const Declaration *decl_ptr)
32     : m_name(name), m_declaration(decl_ptr) {}
33 
34 FunctionInfo::FunctionInfo(const ConstString &name, const Declaration *decl_ptr)
35     : m_name(name), m_declaration(decl_ptr) {}
36 
37 FunctionInfo::~FunctionInfo() {}
38 
39 void FunctionInfo::Dump(Stream *s, bool show_fullpaths) const {
40   if (m_name)
41     *s << ", name = \"" << m_name << "\"";
42   m_declaration.Dump(s, show_fullpaths);
43 }
44 
45 int FunctionInfo::Compare(const FunctionInfo &a, const FunctionInfo &b) {
46   int result = ConstString::Compare(a.GetName(), b.GetName());
47   if (result)
48     return result;
49 
50   return Declaration::Compare(a.m_declaration, b.m_declaration);
51 }
52 
53 Declaration &FunctionInfo::GetDeclaration() { return m_declaration; }
54 
55 const Declaration &FunctionInfo::GetDeclaration() const {
56   return m_declaration;
57 }
58 
59 ConstString FunctionInfo::GetName() const { return m_name; }
60 
61 size_t FunctionInfo::MemorySize() const {
62   return m_name.MemorySize() + m_declaration.MemorySize();
63 }
64 
65 InlineFunctionInfo::InlineFunctionInfo(const char *name, const char *mangled,
66                                        const Declaration *decl_ptr,
67                                        const Declaration *call_decl_ptr)
68     : FunctionInfo(name, decl_ptr), m_mangled(ConstString(mangled), true),
69       m_call_decl(call_decl_ptr) {}
70 
71 InlineFunctionInfo::InlineFunctionInfo(const ConstString &name,
72                                        const Mangled &mangled,
73                                        const Declaration *decl_ptr,
74                                        const Declaration *call_decl_ptr)
75     : FunctionInfo(name, decl_ptr), m_mangled(mangled),
76       m_call_decl(call_decl_ptr) {}
77 
78 InlineFunctionInfo::~InlineFunctionInfo() {}
79 
80 int InlineFunctionInfo::Compare(const InlineFunctionInfo &a,
81                                 const InlineFunctionInfo &b) {
82 
83   int result = FunctionInfo::Compare(a, b);
84   if (result)
85     return result;
86   // only compare the mangled names if both have them
87   return Mangled::Compare(a.m_mangled, a.m_mangled);
88 }
89 
90 void InlineFunctionInfo::Dump(Stream *s, bool show_fullpaths) const {
91   FunctionInfo::Dump(s, show_fullpaths);
92   if (m_mangled)
93     m_mangled.Dump(s);
94 }
95 
96 void InlineFunctionInfo::DumpStopContext(Stream *s,
97                                          LanguageType language) const {
98   //    s->Indent("[inlined] ");
99   s->Indent();
100   if (m_mangled)
101     s->PutCString(m_mangled.GetName(language).AsCString());
102   else
103     s->PutCString(m_name.AsCString());
104 }
105 
106 ConstString InlineFunctionInfo::GetName(LanguageType language) const {
107   if (m_mangled)
108     return m_mangled.GetName(language);
109   return m_name;
110 }
111 
112 ConstString InlineFunctionInfo::GetDisplayName(LanguageType language) const {
113   if (m_mangled)
114     return m_mangled.GetDisplayDemangledName(language);
115   return m_name;
116 }
117 
118 Declaration &InlineFunctionInfo::GetCallSite() { return m_call_decl; }
119 
120 const Declaration &InlineFunctionInfo::GetCallSite() const {
121   return m_call_decl;
122 }
123 
124 Mangled &InlineFunctionInfo::GetMangled() { return m_mangled; }
125 
126 const Mangled &InlineFunctionInfo::GetMangled() const { return m_mangled; }
127 
128 size_t InlineFunctionInfo::MemorySize() const {
129   return FunctionInfo::MemorySize() + m_mangled.MemorySize();
130 }
131 
132 //----------------------------------------------------------------------
133 //
134 //----------------------------------------------------------------------
135 Function::Function(CompileUnit *comp_unit, lldb::user_id_t func_uid,
136                    lldb::user_id_t type_uid, const Mangled &mangled, Type *type,
137                    const AddressRange &range)
138     : UserID(func_uid), m_comp_unit(comp_unit), m_type_uid(type_uid),
139       m_type(type), m_mangled(mangled), m_block(func_uid), m_range(range),
140       m_frame_base(nullptr), m_flags(), m_prologue_byte_size(0) {
141   m_block.SetParentScope(this);
142   assert(comp_unit != nullptr);
143 }
144 
145 Function::Function(CompileUnit *comp_unit, lldb::user_id_t func_uid,
146                    lldb::user_id_t type_uid, const char *mangled, Type *type,
147                    const AddressRange &range)
148     : UserID(func_uid), m_comp_unit(comp_unit), m_type_uid(type_uid),
149       m_type(type), m_mangled(ConstString(mangled), true), m_block(func_uid),
150       m_range(range), m_frame_base(nullptr), m_flags(),
151       m_prologue_byte_size(0) {
152   m_block.SetParentScope(this);
153   assert(comp_unit != nullptr);
154 }
155 
156 Function::~Function() {}
157 
158 void Function::GetStartLineSourceInfo(FileSpec &source_file,
159                                       uint32_t &line_no) {
160   line_no = 0;
161   source_file.Clear();
162 
163   if (m_comp_unit == nullptr)
164     return;
165 
166   if (m_type != nullptr && m_type->GetDeclaration().GetLine() != 0) {
167     source_file = m_type->GetDeclaration().GetFile();
168     line_no = m_type->GetDeclaration().GetLine();
169   } else {
170     LineTable *line_table = m_comp_unit->GetLineTable();
171     if (line_table == nullptr)
172       return;
173 
174     LineEntry line_entry;
175     if (line_table->FindLineEntryByAddress(GetAddressRange().GetBaseAddress(),
176                                            line_entry, nullptr)) {
177       line_no = line_entry.line;
178       source_file = line_entry.file;
179     }
180   }
181 }
182 
183 void Function::GetEndLineSourceInfo(FileSpec &source_file, uint32_t &line_no) {
184   line_no = 0;
185   source_file.Clear();
186 
187   // The -1 is kind of cheesy, but I want to get the last line entry for the
188   // given function, not the
189   // first entry of the next.
190   Address scratch_addr(GetAddressRange().GetBaseAddress());
191   scratch_addr.SetOffset(scratch_addr.GetOffset() +
192                          GetAddressRange().GetByteSize() - 1);
193 
194   LineTable *line_table = m_comp_unit->GetLineTable();
195   if (line_table == nullptr)
196     return;
197 
198   LineEntry line_entry;
199   if (line_table->FindLineEntryByAddress(scratch_addr, line_entry, nullptr)) {
200     line_no = line_entry.line;
201     source_file = line_entry.file;
202   }
203 }
204 
205 Block &Function::GetBlock(bool can_create) {
206   if (!m_block.BlockInfoHasBeenParsed() && can_create) {
207     SymbolContext sc;
208     CalculateSymbolContext(&sc);
209     if (sc.module_sp) {
210       sc.module_sp->GetSymbolVendor()->ParseFunctionBlocks(sc);
211     } else {
212       Host::SystemLog(Host::eSystemLogError, "error: unable to find module "
213                                              "shared pointer for function '%s' "
214                                              "in %s\n",
215                       GetName().GetCString(), m_comp_unit->GetPath().c_str());
216     }
217     m_block.SetBlockInfoHasBeenParsed(true, true);
218   }
219   return m_block;
220 }
221 
222 CompileUnit *Function::GetCompileUnit() { return m_comp_unit; }
223 
224 const CompileUnit *Function::GetCompileUnit() const { return m_comp_unit; }
225 
226 void Function::GetDescription(Stream *s, lldb::DescriptionLevel level,
227                               Target *target) {
228   Type *func_type = GetType();
229   const char *name = func_type ? func_type->GetName().AsCString() : "<unknown>";
230 
231   *s << "id = " << (const UserID &)*this << ", name = \"" << name
232      << "\", range = ";
233 
234   Address::DumpStyle fallback_style;
235   if (level == eDescriptionLevelVerbose)
236     fallback_style = Address::DumpStyleModuleWithFileAddress;
237   else
238     fallback_style = Address::DumpStyleFileAddress;
239   GetAddressRange().Dump(s, target, Address::DumpStyleLoadAddress,
240                          fallback_style);
241 }
242 
243 void Function::Dump(Stream *s, bool show_context) const {
244   s->Printf("%p: ", static_cast<const void *>(this));
245   s->Indent();
246   *s << "Function" << static_cast<const UserID &>(*this);
247 
248   m_mangled.Dump(s);
249 
250   if (m_type)
251     s->Printf(", type = %p", static_cast<void *>(m_type));
252   else if (m_type_uid != LLDB_INVALID_UID)
253     s->Printf(", type_uid = 0x%8.8" PRIx64, m_type_uid);
254 
255   s->EOL();
256   // Dump the root object
257   if (m_block.BlockInfoHasBeenParsed())
258     m_block.Dump(s, m_range.GetBaseAddress().GetFileAddress(), INT_MAX,
259                  show_context);
260 }
261 
262 void Function::CalculateSymbolContext(SymbolContext *sc) {
263   sc->function = this;
264   m_comp_unit->CalculateSymbolContext(sc);
265 }
266 
267 ModuleSP Function::CalculateSymbolContextModule() {
268   SectionSP section_sp(m_range.GetBaseAddress().GetSection());
269   if (section_sp)
270     return section_sp->GetModule();
271 
272   return this->GetCompileUnit()->GetModule();
273 }
274 
275 CompileUnit *Function::CalculateSymbolContextCompileUnit() {
276   return this->GetCompileUnit();
277 }
278 
279 Function *Function::CalculateSymbolContextFunction() { return this; }
280 
281 lldb::DisassemblerSP Function::GetInstructions(const ExecutionContext &exe_ctx,
282                                                const char *flavor,
283                                                bool prefer_file_cache) {
284   ModuleSP module_sp(GetAddressRange().GetBaseAddress().GetModule());
285   if (module_sp) {
286     const bool prefer_file_cache = false;
287     return Disassembler::DisassembleRange(module_sp->GetArchitecture(), nullptr,
288                                           flavor, exe_ctx, GetAddressRange(),
289                                           prefer_file_cache);
290   }
291   return lldb::DisassemblerSP();
292 }
293 
294 bool Function::GetDisassembly(const ExecutionContext &exe_ctx,
295                               const char *flavor, bool prefer_file_cache,
296                               Stream &strm) {
297   lldb::DisassemblerSP disassembler_sp =
298       GetInstructions(exe_ctx, flavor, prefer_file_cache);
299   if (disassembler_sp) {
300     const bool show_address = true;
301     const bool show_bytes = false;
302     disassembler_sp->GetInstructionList().Dump(&strm, show_address, show_bytes,
303                                                &exe_ctx);
304     return true;
305   }
306   return false;
307 }
308 
309 // Symbol *
310 // Function::CalculateSymbolContextSymbol ()
311 //{
312 //    return // TODO: find the symbol for the function???
313 //}
314 
315 void Function::DumpSymbolContext(Stream *s) {
316   m_comp_unit->DumpSymbolContext(s);
317   s->Printf(", Function{0x%8.8" PRIx64 "}", GetID());
318 }
319 
320 size_t Function::MemorySize() const {
321   size_t mem_size = sizeof(Function) + m_block.MemorySize();
322   return mem_size;
323 }
324 
325 bool Function::GetIsOptimized() {
326   bool result = false;
327 
328   // Currently optimization is only indicted by the
329   // vendor extension DW_AT_APPLE_optimized which
330   // is set on a compile unit level.
331   if (m_comp_unit) {
332     result = m_comp_unit->GetIsOptimized();
333   }
334   return result;
335 }
336 
337 bool Function::IsTopLevelFunction() {
338   bool result = false;
339 
340   if (Language *language = Language::FindPlugin(GetLanguage()))
341     result = language->IsTopLevelFunction(*this);
342 
343   return result;
344 }
345 
346 ConstString Function::GetDisplayName() const {
347   if (!m_mangled)
348     return ConstString();
349   return m_mangled.GetDisplayDemangledName(GetLanguage());
350 }
351 
352 CompilerDeclContext Function::GetDeclContext() {
353   ModuleSP module_sp = CalculateSymbolContextModule();
354 
355   if (module_sp) {
356     SymbolVendor *sym_vendor = module_sp->GetSymbolVendor();
357 
358     if (sym_vendor) {
359       SymbolFile *sym_file = sym_vendor->GetSymbolFile();
360 
361       if (sym_file)
362         return sym_file->GetDeclContextForUID(GetID());
363     }
364   }
365   return CompilerDeclContext();
366 }
367 
368 Type *Function::GetType() {
369   if (m_type == nullptr) {
370     SymbolContext sc;
371 
372     CalculateSymbolContext(&sc);
373 
374     if (!sc.module_sp)
375       return nullptr;
376 
377     SymbolVendor *sym_vendor = sc.module_sp->GetSymbolVendor();
378 
379     if (sym_vendor == nullptr)
380       return nullptr;
381 
382     SymbolFile *sym_file = sym_vendor->GetSymbolFile();
383 
384     if (sym_file == nullptr)
385       return nullptr;
386 
387     m_type = sym_file->ResolveTypeUID(m_type_uid);
388   }
389   return m_type;
390 }
391 
392 const Type *Function::GetType() const { return m_type; }
393 
394 CompilerType Function::GetCompilerType() {
395   Type *function_type = GetType();
396   if (function_type)
397     return function_type->GetFullCompilerType();
398   return CompilerType();
399 }
400 
401 uint32_t Function::GetPrologueByteSize() {
402   if (m_prologue_byte_size == 0 &&
403       m_flags.IsClear(flagsCalculatedPrologueSize)) {
404     m_flags.Set(flagsCalculatedPrologueSize);
405     LineTable *line_table = m_comp_unit->GetLineTable();
406     uint32_t prologue_end_line_idx = 0;
407 
408     if (line_table) {
409       LineEntry first_line_entry;
410       uint32_t first_line_entry_idx = UINT32_MAX;
411       if (line_table->FindLineEntryByAddress(GetAddressRange().GetBaseAddress(),
412                                              first_line_entry,
413                                              &first_line_entry_idx)) {
414         // Make sure the first line entry isn't already the end of the prologue
415         addr_t prologue_end_file_addr = LLDB_INVALID_ADDRESS;
416         addr_t line_zero_end_file_addr = LLDB_INVALID_ADDRESS;
417 
418         if (first_line_entry.is_prologue_end) {
419           prologue_end_file_addr =
420               first_line_entry.range.GetBaseAddress().GetFileAddress();
421           prologue_end_line_idx = first_line_entry_idx;
422         } else {
423           // Check the first few instructions and look for one that has
424           // is_prologue_end set to true.
425           const uint32_t last_line_entry_idx = first_line_entry_idx + 6;
426           for (uint32_t idx = first_line_entry_idx + 1;
427                idx < last_line_entry_idx; ++idx) {
428             LineEntry line_entry;
429             if (line_table->GetLineEntryAtIndex(idx, line_entry)) {
430               if (line_entry.is_prologue_end) {
431                 prologue_end_file_addr =
432                     line_entry.range.GetBaseAddress().GetFileAddress();
433                 prologue_end_line_idx = idx;
434                 break;
435               }
436             }
437           }
438         }
439 
440         // If we didn't find the end of the prologue in the line tables,
441         // then just use the end address of the first line table entry
442         if (prologue_end_file_addr == LLDB_INVALID_ADDRESS) {
443           // Check the first few instructions and look for one that has
444           // a line number that's different than the first entry.
445           uint32_t last_line_entry_idx = first_line_entry_idx + 6;
446           for (uint32_t idx = first_line_entry_idx + 1;
447                idx < last_line_entry_idx; ++idx) {
448             LineEntry line_entry;
449             if (line_table->GetLineEntryAtIndex(idx, line_entry)) {
450               if (line_entry.line != first_line_entry.line) {
451                 prologue_end_file_addr =
452                     line_entry.range.GetBaseAddress().GetFileAddress();
453                 prologue_end_line_idx = idx;
454                 break;
455               }
456             }
457           }
458 
459           if (prologue_end_file_addr == LLDB_INVALID_ADDRESS) {
460             prologue_end_file_addr =
461                 first_line_entry.range.GetBaseAddress().GetFileAddress() +
462                 first_line_entry.range.GetByteSize();
463             prologue_end_line_idx = first_line_entry_idx;
464           }
465         }
466 
467         const addr_t func_start_file_addr =
468             m_range.GetBaseAddress().GetFileAddress();
469         const addr_t func_end_file_addr =
470             func_start_file_addr + m_range.GetByteSize();
471 
472         // Now calculate the offset to pass the subsequent line 0 entries.
473         uint32_t first_non_zero_line = prologue_end_line_idx;
474         while (1) {
475           LineEntry line_entry;
476           if (line_table->GetLineEntryAtIndex(first_non_zero_line,
477                                               line_entry)) {
478             if (line_entry.line != 0)
479               break;
480           }
481           if (line_entry.range.GetBaseAddress().GetFileAddress() >=
482               func_end_file_addr)
483             break;
484 
485           first_non_zero_line++;
486         }
487 
488         if (first_non_zero_line > prologue_end_line_idx) {
489           LineEntry first_non_zero_entry;
490           if (line_table->GetLineEntryAtIndex(first_non_zero_line,
491                                               first_non_zero_entry)) {
492             line_zero_end_file_addr =
493                 first_non_zero_entry.range.GetBaseAddress().GetFileAddress();
494           }
495         }
496 
497         // Verify that this prologue end file address in the function's
498         // address range just to be sure
499         if (func_start_file_addr < prologue_end_file_addr &&
500             prologue_end_file_addr < func_end_file_addr) {
501           m_prologue_byte_size = prologue_end_file_addr - func_start_file_addr;
502         }
503 
504         if (prologue_end_file_addr < line_zero_end_file_addr &&
505             line_zero_end_file_addr < func_end_file_addr) {
506           m_prologue_byte_size +=
507               line_zero_end_file_addr - prologue_end_file_addr;
508         }
509       }
510     }
511   }
512 
513   return m_prologue_byte_size;
514 }
515 
516 lldb::LanguageType Function::GetLanguage() const {
517   if (m_comp_unit)
518     return m_comp_unit->GetLanguage();
519   else
520     return lldb::eLanguageTypeUnknown;
521 }
522 
523 ConstString Function::GetName() const {
524   LanguageType language = lldb::eLanguageTypeUnknown;
525   if (m_comp_unit)
526     language = m_comp_unit->GetLanguage();
527   return m_mangled.GetName(language);
528 }
529 
530 ConstString Function::GetNameNoArguments() const {
531   LanguageType language = lldb::eLanguageTypeUnknown;
532   if (m_comp_unit)
533     language = m_comp_unit->GetLanguage();
534   return m_mangled.GetName(language, Mangled::ePreferDemangledWithoutArguments);
535 }
536