1 //===-- DWARFDIE.cpp ------------------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #include "DWARFDIE.h" 10 11 #include "DWARFASTParser.h" 12 #include "DWARFDebugInfo.h" 13 #include "DWARFDebugInfoEntry.h" 14 #include "DWARFDeclContext.h" 15 #include "DWARFUnit.h" 16 17 #include "llvm/ADT/iterator.h" 18 19 using namespace lldb_private; 20 using namespace lldb_private::dwarf; 21 22 namespace { 23 24 /// Iterate through all DIEs elaborating (i.e. reachable by a chain of 25 /// DW_AT_specification and DW_AT_abstract_origin attributes) a given DIE. For 26 /// convenience, the starting die is included in the sequence as the first 27 /// item. 28 class ElaboratingDIEIterator 29 : public llvm::iterator_facade_base< 30 ElaboratingDIEIterator, std::input_iterator_tag, DWARFDIE, 31 std::ptrdiff_t, DWARFDIE *, DWARFDIE *> { 32 33 // The operating invariant is: top of m_worklist contains the "current" item 34 // and the rest of the list are items yet to be visited. An empty worklist 35 // means we've reached the end. 36 // Infinite recursion is prevented by maintaining a list of seen DIEs. 37 // Container sizes are optimized for the case of following DW_AT_specification 38 // and DW_AT_abstract_origin just once. 39 llvm::SmallVector<DWARFDIE, 2> m_worklist; 40 llvm::SmallSet<DWARFDebugInfoEntry *, 3> m_seen; 41 42 void Next() { 43 assert(!m_worklist.empty() && "Incrementing end iterator?"); 44 45 // Pop the current item from the list. 46 DWARFDIE die = m_worklist.back(); 47 m_worklist.pop_back(); 48 49 // And add back any items that elaborate it. 50 for (dw_attr_t attr : {DW_AT_specification, DW_AT_abstract_origin}) { 51 if (DWARFDIE d = die.GetReferencedDIE(attr)) 52 if (m_seen.insert(die.GetDIE()).second) 53 m_worklist.push_back(d); 54 } 55 } 56 57 public: 58 /// An iterator starting at die d. 59 explicit ElaboratingDIEIterator(DWARFDIE d) : m_worklist(1, d) {} 60 61 /// End marker 62 ElaboratingDIEIterator() = default; 63 64 const DWARFDIE &operator*() const { return m_worklist.back(); } 65 ElaboratingDIEIterator &operator++() { 66 Next(); 67 return *this; 68 } 69 70 friend bool operator==(const ElaboratingDIEIterator &a, 71 const ElaboratingDIEIterator &b) { 72 if (a.m_worklist.empty() || b.m_worklist.empty()) 73 return a.m_worklist.empty() == b.m_worklist.empty(); 74 return a.m_worklist.back() == b.m_worklist.back(); 75 } 76 }; 77 78 llvm::iterator_range<ElaboratingDIEIterator> 79 elaborating_dies(const DWARFDIE &die) { 80 return llvm::make_range(ElaboratingDIEIterator(die), 81 ElaboratingDIEIterator()); 82 } 83 } // namespace 84 85 DWARFDIE 86 DWARFDIE::GetParent() const { 87 if (IsValid()) 88 return DWARFDIE(m_cu, m_die->GetParent()); 89 else 90 return DWARFDIE(); 91 } 92 93 DWARFDIE 94 DWARFDIE::GetFirstChild() const { 95 if (IsValid()) 96 return DWARFDIE(m_cu, m_die->GetFirstChild()); 97 else 98 return DWARFDIE(); 99 } 100 101 DWARFDIE 102 DWARFDIE::GetSibling() const { 103 if (IsValid()) 104 return DWARFDIE(m_cu, m_die->GetSibling()); 105 else 106 return DWARFDIE(); 107 } 108 109 DWARFDIE 110 DWARFDIE::GetReferencedDIE(const dw_attr_t attr) const { 111 if (IsValid()) 112 return m_die->GetAttributeValueAsReference(GetCU(), attr); 113 else 114 return {}; 115 } 116 117 DWARFDIE 118 DWARFDIE::GetDIE(dw_offset_t die_offset) const { 119 if (IsValid()) 120 return m_cu->GetDIE(die_offset); 121 else 122 return DWARFDIE(); 123 } 124 125 DWARFDIE 126 DWARFDIE::GetAttributeValueAsReferenceDIE(const dw_attr_t attr) const { 127 if (IsValid()) { 128 DWARFUnit *cu = GetCU(); 129 const bool check_specification_or_abstract_origin = true; 130 DWARFFormValue form_value; 131 if (m_die->GetAttributeValue(cu, attr, form_value, nullptr, 132 check_specification_or_abstract_origin)) 133 return form_value.Reference(); 134 } 135 return DWARFDIE(); 136 } 137 138 DWARFDIE 139 DWARFDIE::LookupDeepestBlock(lldb::addr_t address) const { 140 if (!IsValid()) 141 return DWARFDIE(); 142 143 DWARFDIE result; 144 bool check_children = false; 145 bool match_addr_range = false; 146 switch (Tag()) { 147 case DW_TAG_class_type: 148 case DW_TAG_namespace: 149 case DW_TAG_structure_type: 150 case DW_TAG_common_block: 151 check_children = true; 152 break; 153 case DW_TAG_compile_unit: 154 case DW_TAG_module: 155 case DW_TAG_catch_block: 156 case DW_TAG_subprogram: 157 case DW_TAG_try_block: 158 case DW_TAG_partial_unit: 159 match_addr_range = true; 160 break; 161 case DW_TAG_lexical_block: 162 case DW_TAG_inlined_subroutine: 163 check_children = true; 164 match_addr_range = true; 165 break; 166 default: 167 break; 168 } 169 170 if (match_addr_range) { 171 DWARFRangeList ranges; 172 if (m_die->GetAttributeAddressRanges(m_cu, ranges, 173 /*check_hi_lo_pc=*/true) && 174 ranges.FindEntryThatContains(address)) { 175 check_children = true; 176 switch (Tag()) { 177 default: 178 break; 179 180 case DW_TAG_inlined_subroutine: // Inlined Function 181 case DW_TAG_lexical_block: // Block { } in code 182 result = *this; 183 break; 184 } 185 } else { 186 check_children = false; 187 } 188 } 189 190 if (check_children) { 191 for (DWARFDIE child : children()) { 192 if (DWARFDIE child_result = child.LookupDeepestBlock(address)) 193 return child_result; 194 } 195 } 196 return result; 197 } 198 199 const char *DWARFDIE::GetMangledName() const { 200 if (IsValid()) 201 return m_die->GetMangledName(m_cu); 202 else 203 return nullptr; 204 } 205 206 const char *DWARFDIE::GetPubname() const { 207 if (IsValid()) 208 return m_die->GetPubname(m_cu); 209 else 210 return nullptr; 211 } 212 213 // GetName 214 // 215 // Get value of the DW_AT_name attribute and place that value into the supplied 216 // stream object. If the DIE is a NULL object "NULL" is placed into the stream, 217 // and if no DW_AT_name attribute exists for the DIE then nothing is printed. 218 void DWARFDIE::GetName(Stream &s) const { 219 if (!IsValid()) 220 return; 221 if (GetDIE()->IsNULL()) { 222 s.PutCString("NULL"); 223 return; 224 } 225 const char *name = GetDIE()->GetAttributeValueAsString(GetCU(), DW_AT_name, nullptr, true); 226 if (!name) 227 return; 228 s.PutCString(name); 229 } 230 231 // AppendTypeName 232 // 233 // Follows the type name definition down through all needed tags to end up with 234 // a fully qualified type name and dump the results to the supplied stream. 235 // This is used to show the name of types given a type identifier. 236 void DWARFDIE::AppendTypeName(Stream &s) const { 237 if (!IsValid()) 238 return; 239 if (GetDIE()->IsNULL()) { 240 s.PutCString("NULL"); 241 return; 242 } 243 if (const char *name = GetPubname()) { 244 s.PutCString(name); 245 return; 246 } 247 switch (Tag()) { 248 case DW_TAG_array_type: 249 break; // print out a "[]" after printing the full type of the element 250 // below 251 case DW_TAG_base_type: 252 s.PutCString("base "); 253 break; 254 case DW_TAG_class_type: 255 s.PutCString("class "); 256 break; 257 case DW_TAG_const_type: 258 s.PutCString("const "); 259 break; 260 case DW_TAG_enumeration_type: 261 s.PutCString("enum "); 262 break; 263 case DW_TAG_file_type: 264 s.PutCString("file "); 265 break; 266 case DW_TAG_interface_type: 267 s.PutCString("interface "); 268 break; 269 case DW_TAG_packed_type: 270 s.PutCString("packed "); 271 break; 272 case DW_TAG_pointer_type: 273 break; // print out a '*' after printing the full type below 274 case DW_TAG_ptr_to_member_type: 275 break; // print out a '*' after printing the full type below 276 case DW_TAG_reference_type: 277 break; // print out a '&' after printing the full type below 278 case DW_TAG_restrict_type: 279 s.PutCString("restrict "); 280 break; 281 case DW_TAG_set_type: 282 s.PutCString("set "); 283 break; 284 case DW_TAG_shared_type: 285 s.PutCString("shared "); 286 break; 287 case DW_TAG_string_type: 288 s.PutCString("string "); 289 break; 290 case DW_TAG_structure_type: 291 s.PutCString("struct "); 292 break; 293 case DW_TAG_subrange_type: 294 s.PutCString("subrange "); 295 break; 296 case DW_TAG_subroutine_type: 297 s.PutCString("function "); 298 break; 299 case DW_TAG_thrown_type: 300 s.PutCString("thrown "); 301 break; 302 case DW_TAG_union_type: 303 s.PutCString("union "); 304 break; 305 case DW_TAG_unspecified_type: 306 s.PutCString("unspecified "); 307 break; 308 case DW_TAG_volatile_type: 309 s.PutCString("volatile "); 310 break; 311 case DW_TAG_LLVM_ptrauth_type: { 312 unsigned key = GetAttributeValueAsUnsigned(DW_AT_LLVM_ptrauth_key, 0); 313 bool isAddressDiscriminated = GetAttributeValueAsUnsigned( 314 DW_AT_LLVM_ptrauth_address_discriminated, 0); 315 unsigned extraDiscriminator = 316 GetAttributeValueAsUnsigned(DW_AT_LLVM_ptrauth_extra_discriminator, 0); 317 bool isaPointer = 318 GetAttributeValueAsUnsigned(DW_AT_LLVM_ptrauth_isa_pointer, 0); 319 s.Printf("__ptrauth(%d, %d, 0x0%x, %d)", key, isAddressDiscriminated, 320 extraDiscriminator, isaPointer); 321 break; 322 } 323 default: 324 return; 325 } 326 327 // Follow the DW_AT_type if possible 328 if (DWARFDIE next_die = GetAttributeValueAsReferenceDIE(DW_AT_type)) 329 next_die.AppendTypeName(s); 330 331 switch (Tag()) { 332 case DW_TAG_array_type: 333 s.PutCString("[]"); 334 break; 335 case DW_TAG_pointer_type: 336 s.PutChar('*'); 337 break; 338 case DW_TAG_ptr_to_member_type: 339 s.PutChar('*'); 340 break; 341 case DW_TAG_reference_type: 342 s.PutChar('&'); 343 break; 344 default: 345 break; 346 } 347 } 348 349 lldb_private::Type *DWARFDIE::ResolveType() const { 350 if (IsValid()) 351 return GetDWARF()->ResolveType(*this, true); 352 else 353 return nullptr; 354 } 355 356 lldb_private::Type *DWARFDIE::ResolveTypeUID(const DWARFDIE &die) const { 357 if (SymbolFileDWARF *dwarf = GetDWARF()) 358 return dwarf->ResolveTypeUID(die, true); 359 return nullptr; 360 } 361 362 std::vector<DWARFDIE> DWARFDIE::GetDeclContextDIEs() const { 363 if (!IsValid()) 364 return {}; 365 366 std::vector<DWARFDIE> result; 367 DWARFDIE parent = GetParentDeclContextDIE(); 368 while (parent.IsValid() && parent.GetDIE() != GetDIE()) { 369 result.push_back(std::move(parent)); 370 parent = parent.GetParentDeclContextDIE(); 371 } 372 373 return result; 374 } 375 376 void DWARFDIE::GetDeclContext( 377 llvm::SmallVectorImpl<lldb_private::CompilerContext> &context) const { 378 const dw_tag_t tag = Tag(); 379 if (tag == DW_TAG_compile_unit || tag == DW_TAG_partial_unit) 380 return; 381 DWARFDIE parent = GetParent(); 382 if (parent) 383 parent.GetDeclContext(context); 384 switch (tag) { 385 case DW_TAG_module: 386 context.push_back({CompilerContextKind::Module, ConstString(GetName())}); 387 break; 388 case DW_TAG_namespace: 389 context.push_back({CompilerContextKind::Namespace, ConstString(GetName())}); 390 break; 391 case DW_TAG_structure_type: 392 context.push_back({CompilerContextKind::Struct, ConstString(GetName())}); 393 break; 394 case DW_TAG_union_type: 395 context.push_back({CompilerContextKind::Union, ConstString(GetName())}); 396 break; 397 case DW_TAG_class_type: 398 context.push_back({CompilerContextKind::Class, ConstString(GetName())}); 399 break; 400 case DW_TAG_enumeration_type: 401 context.push_back({CompilerContextKind::Enum, ConstString(GetName())}); 402 break; 403 case DW_TAG_subprogram: 404 context.push_back( 405 {CompilerContextKind::Function, ConstString(GetPubname())}); 406 break; 407 case DW_TAG_variable: 408 context.push_back( 409 {CompilerContextKind::Variable, ConstString(GetPubname())}); 410 break; 411 case DW_TAG_typedef: 412 context.push_back({CompilerContextKind::Typedef, ConstString(GetName())}); 413 break; 414 default: 415 break; 416 } 417 } 418 419 DWARFDIE 420 DWARFDIE::GetParentDeclContextDIE() const { 421 if (IsValid()) 422 return m_die->GetParentDeclContextDIE(m_cu); 423 else 424 return DWARFDIE(); 425 } 426 427 bool DWARFDIE::IsStructUnionOrClass() const { 428 const dw_tag_t tag = Tag(); 429 return tag == DW_TAG_class_type || tag == DW_TAG_structure_type || 430 tag == DW_TAG_union_type; 431 } 432 433 bool DWARFDIE::IsMethod() const { 434 for (DWARFDIE d : elaborating_dies(*this)) 435 if (d.GetParent().IsStructUnionOrClass()) 436 return true; 437 return false; 438 } 439 440 bool DWARFDIE::GetDIENamesAndRanges( 441 const char *&name, const char *&mangled, DWARFRangeList &ranges, 442 int &decl_file, int &decl_line, int &decl_column, int &call_file, 443 int &call_line, int &call_column, 444 lldb_private::DWARFExpressionList *frame_base) const { 445 if (IsValid()) { 446 return m_die->GetDIENamesAndRanges( 447 GetCU(), name, mangled, ranges, decl_file, decl_line, decl_column, 448 call_file, call_line, call_column, frame_base); 449 } else 450 return false; 451 } 452 453 llvm::iterator_range<DWARFDIE::child_iterator> DWARFDIE::children() const { 454 return llvm::make_range(child_iterator(*this), child_iterator()); 455 } 456