contrib/llvm/lib/BinaryFormat/Dwarf.cpp

   1 //===-- llvm/BinaryFormat/Dwarf.cpp - Dwarf Framework ------------*- 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 // This file contains support for generic dwarf information.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "llvm/BinaryFormat/Dwarf.h"
  15 #include "llvm/ADT/StringSwitch.h"
  16 #include "llvm/Support/ErrorHandling.h"
  17
  18 using namespace llvm;
  19 using namespace dwarf;
  20
  21 StringRef llvm::dwarf::TagString(unsigned Tag) {
  22   switch (Tag) {
  23   default:
  24     return StringRef();
  25 #define HANDLE_DW_TAG(ID, NAME, VERSION, VENDOR)                               \
  26   case DW_TAG_##NAME:                                                          \
  27     return "DW_TAG_" #NAME;
  28 #include "llvm/BinaryFormat/Dwarf.def"
  29   }
  30 }
  31
  32 unsigned llvm::dwarf::getTag(StringRef TagString) {
  33   return StringSwitch<unsigned>(TagString)
  34 #define HANDLE_DW_TAG(ID, NAME, VERSION, VENDOR)                               \
  35   .Case("DW_TAG_" #NAME, DW_TAG_##NAME)
  36 #include "llvm/BinaryFormat/Dwarf.def"
  37       .Default(DW_TAG_invalid);
  38 }
  39
  40 unsigned llvm::dwarf::TagVersion(dwarf::Tag Tag) {
  41   switch (Tag) {
  42   default:
  43     return 0;
  44 #define HANDLE_DW_TAG(ID, NAME, VERSION, VENDOR)                               \
  45   case DW_TAG_##NAME:                                                          \
  46     return VERSION;
  47 #include "llvm/BinaryFormat/Dwarf.def"
  48   }
  49 }
  50
  51 unsigned llvm::dwarf::TagVendor(dwarf::Tag Tag) {
  52   switch (Tag) {
  53   default:
  54     return 0;
  55 #define HANDLE_DW_TAG(ID, NAME, VERSION, VENDOR)                               \
  56   case DW_TAG_##NAME:                                                          \
  57     return DWARF_VENDOR_##VENDOR;
  58 #include "llvm/BinaryFormat/Dwarf.def"
  59   }
  60 }
  61
  62 StringRef llvm::dwarf::ChildrenString(unsigned Children) {
  63   switch (Children) {
  64   case DW_CHILDREN_no:
  65     return "DW_CHILDREN_no";
  66   case DW_CHILDREN_yes:
  67     return "DW_CHILDREN_yes";
  68   }
  69   return StringRef();
  70 }
  71
  72 StringRef llvm::dwarf::AttributeString(unsigned Attribute) {
  73   switch (Attribute) {
  74   default:
  75     return StringRef();
  76 #define HANDLE_DW_AT(ID, NAME, VERSION, VENDOR)                                \
  77   case DW_AT_##NAME:                                                           \
  78     return "DW_AT_" #NAME;
  79 #include "llvm/BinaryFormat/Dwarf.def"
  80   }
  81 }
  82
  83 unsigned llvm::dwarf::AttributeVersion(dwarf::Attribute Attribute) {
  84   switch (Attribute) {
  85   default:
  86     return 0;
  87 #define HANDLE_DW_AT(ID, NAME, VERSION, VENDOR)                                \
  88   case DW_AT_##NAME:                                                           \
  89     return VERSION;
  90 #include "llvm/BinaryFormat/Dwarf.def"
  91   }
  92 }
  93
  94 unsigned llvm::dwarf::AttributeVendor(dwarf::Attribute Attribute) {
  95   switch (Attribute) {
  96   default:
  97     return 0;
  98 #define HANDLE_DW_AT(ID, NAME, VERSION, VENDOR)                                \
  99   case DW_AT_##NAME:                                                           \
 100     return DWARF_VENDOR_##VENDOR;
 101 #include "llvm/BinaryFormat/Dwarf.def"
 102   }
 103 }
 104
 105 StringRef llvm::dwarf::FormEncodingString(unsigned Encoding) {
 106   switch (Encoding) {
 107   default:
 108     return StringRef();
 109 #define HANDLE_DW_FORM(ID, NAME, VERSION, VENDOR)                              \
 110   case DW_FORM_##NAME:                                                         \
 111     return "DW_FORM_" #NAME;
 112 #include "llvm/BinaryFormat/Dwarf.def"
 113   }
 114 }
 115
 116 unsigned llvm::dwarf::FormVersion(dwarf::Form Form) {
 117   switch (Form) {
 118   default:
 119     return 0;
 120 #define HANDLE_DW_FORM(ID, NAME, VERSION, VENDOR)                              \
 121   case DW_FORM_##NAME:                                                         \
 122     return VERSION;
 123 #include "llvm/BinaryFormat/Dwarf.def"
 124   }
 125 }
 126
 127 unsigned llvm::dwarf::FormVendor(dwarf::Form Form) {
 128   switch (Form) {
 129   default:
 130     return 0;
 131 #define HANDLE_DW_FORM(ID, NAME, VERSION, VENDOR)                              \
 132   case DW_FORM_##NAME:                                                         \
 133     return DWARF_VENDOR_##VENDOR;
 134 #include "llvm/BinaryFormat/Dwarf.def"
 135   }
 136 }
 137
 138 StringRef llvm::dwarf::OperationEncodingString(unsigned Encoding) {
 139   switch (Encoding) {
 140   default:
 141     return StringRef();
 142 #define HANDLE_DW_OP(ID, NAME, VERSION, VENDOR)                                \
 143   case DW_OP_##NAME:                                                           \
 144     return "DW_OP_" #NAME;
 145 #include "llvm/BinaryFormat/Dwarf.def"
 146   case DW_OP_LLVM_fragment:
 147     return "DW_OP_LLVM_fragment";
 148   }
 149 }
 150
 151 unsigned llvm::dwarf::getOperationEncoding(StringRef OperationEncodingString) {
 152   return StringSwitch<unsigned>(OperationEncodingString)
 153 #define HANDLE_DW_OP(ID, NAME, VERSION, VENDOR)                                \
 154   .Case("DW_OP_" #NAME, DW_OP_##NAME)
 155 #include "llvm/BinaryFormat/Dwarf.def"
 156       .Case("DW_OP_LLVM_fragment", DW_OP_LLVM_fragment)
 157       .Default(0);
 158 }
 159
 160 unsigned llvm::dwarf::OperationVersion(dwarf::LocationAtom Op) {
 161   switch (Op) {
 162   default:
 163     return 0;
 164 #define HANDLE_DW_OP(ID, NAME, VERSION, VENDOR)                                \
 165   case DW_OP_##NAME:                                                           \
 166     return VERSION;
 167 #include "llvm/BinaryFormat/Dwarf.def"
 168   }
 169 }
 170
 171 unsigned llvm::dwarf::OperationVendor(dwarf::LocationAtom Op) {
 172   switch (Op) {
 173   default:
 174     return 0;
 175 #define HANDLE_DW_OP(ID, NAME, VERSION, VENDOR)                                \
 176   case DW_OP_##NAME:                                                           \
 177     return DWARF_VENDOR_##VENDOR;
 178 #include "llvm/BinaryFormat/Dwarf.def"
 179   }
 180 }
 181
 182 StringRef llvm::dwarf::AttributeEncodingString(unsigned Encoding) {
 183   switch (Encoding) {
 184   default:
 185     return StringRef();
 186 #define HANDLE_DW_ATE(ID, NAME, VERSION, VENDOR)                               \
 187   case DW_ATE_##NAME:                                                          \
 188     return "DW_ATE_" #NAME;
 189 #include "llvm/BinaryFormat/Dwarf.def"
 190   }
 191 }
 192
 193 unsigned llvm::dwarf::getAttributeEncoding(StringRef EncodingString) {
 194   return StringSwitch<unsigned>(EncodingString)
 195 #define HANDLE_DW_ATE(ID, NAME, VERSION, VENDOR)                               \
 196   .Case("DW_ATE_" #NAME, DW_ATE_##NAME)
 197 #include "llvm/BinaryFormat/Dwarf.def"
 198       .Default(0);
 199 }
 200
 201 unsigned llvm::dwarf::AttributeEncodingVersion(dwarf::TypeKind ATE) {
 202   switch (ATE) {
 203   default:
 204     return 0;
 205 #define HANDLE_DW_ATE(ID, NAME, VERSION, VENDOR)                               \
 206   case DW_ATE_##NAME:                                                          \
 207     return VERSION;
 208 #include "llvm/BinaryFormat/Dwarf.def"
 209   }
 210 }
 211
 212 unsigned llvm::dwarf::AttributeEncodingVendor(dwarf::TypeKind ATE) {
 213   switch (ATE) {
 214   default:
 215     return 0;
 216 #define HANDLE_DW_ATE(ID, NAME, VERSION, VENDOR)                               \
 217   case DW_ATE_##NAME:                                                          \
 218     return DWARF_VENDOR_##VENDOR;
 219 #include "llvm/BinaryFormat/Dwarf.def"
 220   }
 221 }
 222
 223 StringRef llvm::dwarf::DecimalSignString(unsigned Sign) {
 224   switch (Sign) {
 225   case DW_DS_unsigned:
 226     return "DW_DS_unsigned";
 227   case DW_DS_leading_overpunch:
 228     return "DW_DS_leading_overpunch";
 229   case DW_DS_trailing_overpunch:
 230     return "DW_DS_trailing_overpunch";
 231   case DW_DS_leading_separate:
 232     return "DW_DS_leading_separate";
 233   case DW_DS_trailing_separate:
 234     return "DW_DS_trailing_separate";
 235   }
 236   return StringRef();
 237 }
 238
 239 StringRef llvm::dwarf::EndianityString(unsigned Endian) {
 240   switch (Endian) {
 241   case DW_END_default:
 242     return "DW_END_default";
 243   case DW_END_big:
 244     return "DW_END_big";
 245   case DW_END_little:
 246     return "DW_END_little";
 247   case DW_END_lo_user:
 248     return "DW_END_lo_user";
 249   case DW_END_hi_user:
 250     return "DW_END_hi_user";
 251   }
 252   return StringRef();
 253 }
 254
 255 StringRef llvm::dwarf::AccessibilityString(unsigned Access) {
 256   switch (Access) {
 257   // Accessibility codes
 258   case DW_ACCESS_public:
 259     return "DW_ACCESS_public";
 260   case DW_ACCESS_protected:
 261     return "DW_ACCESS_protected";
 262   case DW_ACCESS_private:
 263     return "DW_ACCESS_private";
 264   }
 265   return StringRef();
 266 }
 267
 268 StringRef llvm::dwarf::VisibilityString(unsigned Visibility) {
 269   switch (Visibility) {
 270   case DW_VIS_local:
 271     return "DW_VIS_local";
 272   case DW_VIS_exported:
 273     return "DW_VIS_exported";
 274   case DW_VIS_qualified:
 275     return "DW_VIS_qualified";
 276   }
 277   return StringRef();
 278 }
 279
 280 StringRef llvm::dwarf::VirtualityString(unsigned Virtuality) {
 281   switch (Virtuality) {
 282   default:
 283     return StringRef();
 284 #define HANDLE_DW_VIRTUALITY(ID, NAME)                                         \
 285   case DW_VIRTUALITY_##NAME:                                                   \
 286     return "DW_VIRTUALITY_" #NAME;
 287 #include "llvm/BinaryFormat/Dwarf.def"
 288   }
 289 }
 290
 291 unsigned llvm::dwarf::getVirtuality(StringRef VirtualityString) {
 292   return StringSwitch<unsigned>(VirtualityString)
 293 #define HANDLE_DW_VIRTUALITY(ID, NAME)                                         \
 294   .Case("DW_VIRTUALITY_" #NAME, DW_VIRTUALITY_##NAME)
 295 #include "llvm/BinaryFormat/Dwarf.def"
 296       .Default(DW_VIRTUALITY_invalid);
 297 }
 298
 299 StringRef llvm::dwarf::LanguageString(unsigned Language) {
 300   switch (Language) {
 301   default:
 302     return StringRef();
 303 #define HANDLE_DW_LANG(ID, NAME, VERSION, VENDOR)                              \
 304   case DW_LANG_##NAME:                                                         \
 305     return "DW_LANG_" #NAME;
 306 #include "llvm/BinaryFormat/Dwarf.def"
 307   }
 308 }
 309
 310 unsigned llvm::dwarf::getLanguage(StringRef LanguageString) {
 311   return StringSwitch<unsigned>(LanguageString)
 312 #define HANDLE_DW_LANG(ID, NAME, VERSION, VENDOR)                              \
 313   .Case("DW_LANG_" #NAME, DW_LANG_##NAME)
 314 #include "llvm/BinaryFormat/Dwarf.def"
 315       .Default(0);
 316 }
 317
 318 unsigned llvm::dwarf::LanguageVersion(dwarf::SourceLanguage Lang) {
 319   switch (Lang) {
 320   default:
 321     return 0;
 322 #define HANDLE_DW_LANG(ID, NAME, VERSION, VENDOR)                              \
 323   case DW_LANG_##NAME:                                                         \
 324     return VERSION;
 325 #include "llvm/BinaryFormat/Dwarf.def"
 326   }
 327 }
 328
 329 unsigned llvm::dwarf::LanguageVendor(dwarf::SourceLanguage Lang) {
 330   switch (Lang) {
 331   default:
 332     return 0;
 333 #define HANDLE_DW_LANG(ID, NAME, VERSION, VENDOR)                              \
 334   case DW_LANG_##NAME:                                                         \
 335     return DWARF_VENDOR_##VENDOR;
 336 #include "llvm/BinaryFormat/Dwarf.def"
 337   }
 338 }
 339
 340 StringRef llvm::dwarf::CaseString(unsigned Case) {
 341   switch (Case) {
 342   case DW_ID_case_sensitive:
 343     return "DW_ID_case_sensitive";
 344   case DW_ID_up_case:
 345     return "DW_ID_up_case";
 346   case DW_ID_down_case:
 347     return "DW_ID_down_case";
 348   case DW_ID_case_insensitive:
 349     return "DW_ID_case_insensitive";
 350   }
 351   return StringRef();
 352 }
 353
 354 StringRef llvm::dwarf::ConventionString(unsigned CC) {
 355   switch (CC) {
 356   default:
 357     return StringRef();
 358 #define HANDLE_DW_CC(ID, NAME)                                                 \
 359   case DW_CC_##NAME:                                                           \
 360     return "DW_CC_" #NAME;
 361 #include "llvm/BinaryFormat/Dwarf.def"
 362   }
 363 }
 364
 365 unsigned llvm::dwarf::getCallingConvention(StringRef CCString) {
 366   return StringSwitch<unsigned>(CCString)
 367 #define HANDLE_DW_CC(ID, NAME) .Case("DW_CC_" #NAME, DW_CC_##NAME)
 368 #include "llvm/BinaryFormat/Dwarf.def"
 369       .Default(0);
 370 }
 371
 372 StringRef llvm::dwarf::InlineCodeString(unsigned Code) {
 373   switch (Code) {
 374   case DW_INL_not_inlined:
 375     return "DW_INL_not_inlined";
 376   case DW_INL_inlined:
 377     return "DW_INL_inlined";
 378   case DW_INL_declared_not_inlined:
 379     return "DW_INL_declared_not_inlined";
 380   case DW_INL_declared_inlined:
 381     return "DW_INL_declared_inlined";
 382   }
 383   return StringRef();
 384 }
 385
 386 StringRef llvm::dwarf::ArrayOrderString(unsigned Order) {
 387   switch (Order) {
 388   case DW_ORD_row_major:
 389     return "DW_ORD_row_major";
 390   case DW_ORD_col_major:
 391     return "DW_ORD_col_major";
 392   }
 393   return StringRef();
 394 }
 395
 396 StringRef llvm::dwarf::LNStandardString(unsigned Standard) {
 397   switch (Standard) {
 398   default:
 399     return StringRef();
 400 #define HANDLE_DW_LNS(ID, NAME)                                                \
 401   case DW_LNS_##NAME:                                                          \
 402     return "DW_LNS_" #NAME;
 403 #include "llvm/BinaryFormat/Dwarf.def"
 404   }
 405 }
 406
 407 StringRef llvm::dwarf::LNExtendedString(unsigned Encoding) {
 408   switch (Encoding) {
 409   default:
 410     return StringRef();
 411 #define HANDLE_DW_LNE(ID, NAME)                                                \
 412   case DW_LNE_##NAME:                                                          \
 413     return "DW_LNE_" #NAME;
 414 #include "llvm/BinaryFormat/Dwarf.def"
 415   }
 416 }
 417
 418 StringRef llvm::dwarf::MacinfoString(unsigned Encoding) {
 419   switch (Encoding) {
 420   // Macinfo Type Encodings
 421   case DW_MACINFO_define:
 422     return "DW_MACINFO_define";
 423   case DW_MACINFO_undef:
 424     return "DW_MACINFO_undef";
 425   case DW_MACINFO_start_file:
 426     return "DW_MACINFO_start_file";
 427   case DW_MACINFO_end_file:
 428     return "DW_MACINFO_end_file";
 429   case DW_MACINFO_vendor_ext:
 430     return "DW_MACINFO_vendor_ext";
 431   case DW_MACINFO_invalid:
 432     return "DW_MACINFO_invalid";
 433   }
 434   return StringRef();
 435 }
 436
 437 unsigned llvm::dwarf::getMacinfo(StringRef MacinfoString) {
 438   return StringSwitch<unsigned>(MacinfoString)
 439       .Case("DW_MACINFO_define", DW_MACINFO_define)
 440       .Case("DW_MACINFO_undef", DW_MACINFO_undef)
 441       .Case("DW_MACINFO_start_file", DW_MACINFO_start_file)
 442       .Case("DW_MACINFO_end_file", DW_MACINFO_end_file)
 443       .Case("DW_MACINFO_vendor_ext", DW_MACINFO_vendor_ext)
 444       .Default(DW_MACINFO_invalid);
 445 }
 446
 447 StringRef llvm::dwarf::RangeListEncodingString(unsigned Encoding) {
 448   switch (Encoding) {
 449   default:
 450     return StringRef();
 451 #define HANDLE_DW_RLE(ID, NAME)                                                \
 452   case DW_RLE_##NAME:                                                          \
 453     return "DW_RLE_" #NAME;
 454 #include "llvm/BinaryFormat/Dwarf.def"
 455   }
 456 }
 457
 458 StringRef llvm::dwarf::CallFrameString(unsigned Encoding) {
 459   switch (Encoding) {
 460   default:
 461     return StringRef();
 462 #define HANDLE_DW_CFA(ID, NAME)                                                \
 463   case DW_CFA_##NAME:                                                          \
 464     return "DW_CFA_" #NAME;
 465 #include "llvm/BinaryFormat/Dwarf.def"
 466   }
 467 }
 468
 469 StringRef llvm::dwarf::ApplePropertyString(unsigned Prop) {
 470   switch (Prop) {
 471   default:
 472     return StringRef();
 473 #define HANDLE_DW_APPLE_PROPERTY(ID, NAME)                                     \
 474   case DW_APPLE_PROPERTY_##NAME:                                               \
 475     return "DW_APPLE_PROPERTY_" #NAME;
 476 #include "llvm/BinaryFormat/Dwarf.def"
 477   }
 478 }
 479
 480 StringRef llvm::dwarf::UnitTypeString(unsigned UT) {
 481   switch (UT) {
 482   default:
 483     return StringRef();
 484 #define HANDLE_DW_UT(ID, NAME)                                                 \
 485   case DW_UT_##NAME:                                                           \
 486     return "DW_UT_" #NAME;
 487 #include "llvm/BinaryFormat/Dwarf.def"
 488   }
 489 }
 490
 491 StringRef llvm::dwarf::AtomTypeString(unsigned AT) {
 492   switch (AT) {
 493   case dwarf::DW_ATOM_null:
 494     return "DW_ATOM_null";
 495   case dwarf::DW_ATOM_die_offset:
 496     return "DW_ATOM_die_offset";
 497   case DW_ATOM_cu_offset:
 498     return "DW_ATOM_cu_offset";
 499   case DW_ATOM_die_tag:
 500     return "DW_ATOM_die_tag";
 501   case DW_ATOM_type_flags:
 502   case DW_ATOM_type_type_flags:
 503     return "DW_ATOM_type_flags";
 504   case DW_ATOM_qual_name_hash:
 505     return "DW_ATOM_qual_name_hash";
 506   }
 507   return StringRef();
 508 }
 509
 510 StringRef llvm::dwarf::GDBIndexEntryKindString(GDBIndexEntryKind Kind) {
 511   switch (Kind) {
 512   case GIEK_NONE:
 513     return "NONE";
 514   case GIEK_TYPE:
 515     return "TYPE";
 516   case GIEK_VARIABLE:
 517     return "VARIABLE";
 518   case GIEK_FUNCTION:
 519     return "FUNCTION";
 520   case GIEK_OTHER:
 521     return "OTHER";
 522   case GIEK_UNUSED5:
 523     return "UNUSED5";
 524   case GIEK_UNUSED6:
 525     return "UNUSED6";
 526   case GIEK_UNUSED7:
 527     return "UNUSED7";
 528   }
 529   llvm_unreachable("Unknown GDBIndexEntryKind value");
 530 }
 531
 532 StringRef
 533 llvm::dwarf::GDBIndexEntryLinkageString(GDBIndexEntryLinkage Linkage) {
 534   switch (Linkage) {
 535   case GIEL_EXTERNAL:
 536     return "EXTERNAL";
 537   case GIEL_STATIC:
 538     return "STATIC";
 539   }
 540   llvm_unreachable("Unknown GDBIndexEntryLinkage value");
 541 }
 542
 543 StringRef llvm::dwarf::AttributeValueString(uint16_t Attr, unsigned Val) {
 544   switch (Attr) {
 545   case DW_AT_accessibility:
 546     return AccessibilityString(Val);
 547   case DW_AT_virtuality:
 548     return VirtualityString(Val);
 549   case DW_AT_language:
 550     return LanguageString(Val);
 551   case DW_AT_encoding:
 552     return AttributeEncodingString(Val);
 553   case DW_AT_decimal_sign:
 554     return DecimalSignString(Val);
 555   case DW_AT_endianity:
 556     return EndianityString(Val);
 557   case DW_AT_visibility:
 558     return VisibilityString(Val);
 559   case DW_AT_identifier_case:
 560     return CaseString(Val);
 561   case DW_AT_calling_convention:
 562     return ConventionString(Val);
 563   case DW_AT_inline:
 564     return InlineCodeString(Val);
 565   case DW_AT_ordering:
 566     return ArrayOrderString(Val);
 567   case DW_AT_APPLE_runtime_class:
 568     return LanguageString(Val);
 569   }
 570
 571   return StringRef();
 572 }
 573
 574 StringRef llvm::dwarf::AtomValueString(uint16_t Atom, unsigned Val) {
 575   switch (Atom) {
 576   case DW_ATOM_null:
 577     return "NULL";
 578   case DW_ATOM_die_tag:
 579     return TagString(Val);
 580   }
 581
 582   return StringRef();
 583 }
 584
 585 StringRef llvm::dwarf::IndexString(unsigned Idx) {
 586   switch (Idx) {
 587   default:
 588     return StringRef();
 589 #define HANDLE_DW_IDX(ID, NAME)                                                \
 590   case DW_IDX_##NAME:                                                          \
 591     return "DW_IDX_" #NAME;
 592 #include "llvm/BinaryFormat/Dwarf.def"
 593   }
 594 }
 595
 596 Optional<uint8_t> llvm::dwarf::getFixedFormByteSize(dwarf::Form Form,
 597                                                     FormParams Params) {
 598   switch (Form) {
 599   case DW_FORM_addr:
 600     if (Params)
 601       return Params.AddrSize;
 602     return None;
 603
 604   case DW_FORM_block:          // ULEB128 length L followed by L bytes.
 605   case DW_FORM_block1:         // 1 byte length L followed by L bytes.
 606   case DW_FORM_block2:         // 2 byte length L followed by L bytes.
 607   case DW_FORM_block4:         // 4 byte length L followed by L bytes.
 608   case DW_FORM_string:         // C-string with null terminator.
 609   case DW_FORM_sdata:          // SLEB128.
 610   case DW_FORM_udata:          // ULEB128.
 611   case DW_FORM_ref_udata:      // ULEB128.
 612   case DW_FORM_indirect:       // ULEB128.
 613   case DW_FORM_exprloc:        // ULEB128 length L followed by L bytes.
 614   case DW_FORM_strx:           // ULEB128.
 615   case DW_FORM_addrx:          // ULEB128.
 616   case DW_FORM_loclistx:       // ULEB128.
 617   case DW_FORM_rnglistx:       // ULEB128.
 618   case DW_FORM_GNU_addr_index: // ULEB128.
 619   case DW_FORM_GNU_str_index:  // ULEB128.
 620     return None;
 621
 622   case DW_FORM_ref_addr:
 623     if (Params)
 624       return Params.getRefAddrByteSize();
 625     return None;
 626
 627   case DW_FORM_flag:
 628   case DW_FORM_data1:
 629   case DW_FORM_ref1:
 630   case DW_FORM_strx1:
 631   case DW_FORM_addrx1:
 632     return 1;
 633
 634   case DW_FORM_data2:
 635   case DW_FORM_ref2:
 636   case DW_FORM_strx2:
 637   case DW_FORM_addrx2:
 638     return 2;
 639
 640   case DW_FORM_strx3:
 641     return 3;
 642
 643   case DW_FORM_data4:
 644   case DW_FORM_ref4:
 645   case DW_FORM_ref_sup4:
 646   case DW_FORM_strx4:
 647   case DW_FORM_addrx4:
 648     return 4;
 649
 650   case DW_FORM_strp:
 651   case DW_FORM_GNU_ref_alt:
 652   case DW_FORM_GNU_strp_alt:
 653   case DW_FORM_line_strp:
 654   case DW_FORM_sec_offset:
 655   case DW_FORM_strp_sup:
 656     if (Params)
 657       return Params.getDwarfOffsetByteSize();
 658     return None;
 659
 660   case DW_FORM_data8:
 661   case DW_FORM_ref8:
 662   case DW_FORM_ref_sig8:
 663   case DW_FORM_ref_sup8:
 664     return 8;
 665
 666   case DW_FORM_flag_present:
 667     return 0;
 668
 669   case DW_FORM_data16:
 670     return 16;
 671
 672   case DW_FORM_implicit_const:
 673     // The implicit value is stored in the abbreviation as a SLEB128, and
 674     // there no data in debug info.
 675     return 0;
 676
 677   default:
 678     break;
 679   }
 680   return None;
 681 }
 682
 683 bool llvm::dwarf::isValidFormForVersion(Form F, unsigned Version,
 684                                         bool ExtensionsOk) {
 685   if (FormVendor(F) == DWARF_VENDOR_DWARF) {
 686     unsigned FV = FormVersion(F);
 687     return FV > 0 && FV <= Version;
 688   }
 689   return ExtensionsOk;
 690 }
 691
 692 constexpr char llvm::dwarf::EnumTraits<Attribute>::Type[];
 693 constexpr char llvm::dwarf::EnumTraits<Form>::Type[];
 694 constexpr char llvm::dwarf::EnumTraits<Index>::Type[];
 695 constexpr char llvm::dwarf::EnumTraits<Tag>::Type[];