lib/Analysis/DebugInfo.cpp

   1 //===--- DebugInfo.cpp - Debug Information Helper Classes -----------------===//
   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 implements the helper classes used to build and interpret debug
  11 // information in LLVM IR form.
  12 //
  13 //===----------------------------------------------------------------------===//
  14
  15 #include "llvm/Analysis/DebugInfo.h"
  16 #include "llvm/Constants.h"
  17 #include "llvm/DerivedTypes.h"
  18 #include "llvm/Intrinsics.h"
  19 #include "llvm/IntrinsicInst.h"
  20 #include "llvm/Instructions.h"
  21 #include "llvm/Module.h"
  22 #include "llvm/Analysis/ValueTracking.h"
  23 #include "llvm/Support/Dwarf.h"
  24 #include "llvm/Support/Streams.h"
  25
  26 using namespace llvm;
  27 using namespace llvm::dwarf;
  28
  29 //===----------------------------------------------------------------------===//
  30 // DIDescriptor
  31 //===----------------------------------------------------------------------===//
  32
  33 /// ValidDebugInfo - Return true if V represents valid debug info value.
  34 bool DIDescriptor::ValidDebugInfo(Value *V, CodeGenOpt::Level OptLevel) {
  35   if (!V)
  36     return false;
  37
  38   GlobalVariable *GV = dyn_cast<GlobalVariable>(V->stripPointerCasts());
  39   if (!GV)
  40     return false;
  41
  42   if (!GV->hasInternalLinkage () && !GV->hasLinkOnceLinkage())
  43     return false;
  44
  45   DIDescriptor DI(GV);
  46
  47   // Check current version. Allow Version6 for now.
  48   unsigned Version = DI.getVersion();
  49   if (Version != LLVMDebugVersion && Version != LLVMDebugVersion6)
  50     return false;
  51
  52   unsigned Tag = DI.getTag();
  53   switch (Tag) {
  54   case DW_TAG_variable:
  55     assert(DIVariable(GV).Verify() && "Invalid DebugInfo value");
  56     break;
  57   case DW_TAG_compile_unit:
  58     assert(DICompileUnit(GV).Verify() && "Invalid DebugInfo value");
  59     break;
  60   case DW_TAG_subprogram:
  61     assert(DISubprogram(GV).Verify() && "Invalid DebugInfo value");
  62     break;
  63   case DW_TAG_lexical_block:
  64     // FIXME: This interfers with the quality of generated code during
  65     // optimization.
  66     if (OptLevel != CodeGenOpt::None)
  67       return false;
  68     // FALLTHROUGH
  69   default:
  70     break;
  71   }
  72
  73   return true;
  74 }
  75
  76 DIDescriptor::DIDescriptor(GlobalVariable *gv, unsigned RequiredTag) {
  77   GV = gv;
  78
  79   // If this is non-null, check to see if the Tag matches. If not, set to null.
  80   if (GV && getTag() != RequiredTag)
  81     GV = 0;
  82 }
  83
  84 const std::string &
  85 DIDescriptor::getStringField(unsigned Elt, std::string &Result) const {
  86   if (GV == 0) {
  87     Result.clear();
  88     return Result;
  89   }
  90
  91   Constant *C = GV->getInitializer();
  92   if (C == 0 || Elt >= C->getNumOperands()) {
  93     Result.clear();
  94     return Result;
  95   }
  96
  97   // Fills in the string if it succeeds
  98   if (!GetConstantStringInfo(C->getOperand(Elt), Result))
  99     Result.clear();
 100
 101   return Result;
 102 }
 103
 104 uint64_t DIDescriptor::getUInt64Field(unsigned Elt) const {
 105   if (GV == 0) return 0;
 106
 107   Constant *C = GV->getInitializer();
 108   if (C == 0 || Elt >= C->getNumOperands())
 109     return 0;
 110
 111   if (ConstantInt *CI = dyn_cast<ConstantInt>(C->getOperand(Elt)))
 112     return CI->getZExtValue();
 113   return 0;
 114 }
 115
 116 DIDescriptor DIDescriptor::getDescriptorField(unsigned Elt) const {
 117   if (GV == 0) return DIDescriptor();
 118
 119   Constant *C = GV->getInitializer();
 120   if (C == 0 || Elt >= C->getNumOperands())
 121     return DIDescriptor();
 122
 123   C = C->getOperand(Elt);
 124   return DIDescriptor(dyn_cast<GlobalVariable>(C->stripPointerCasts()));
 125 }
 126
 127 GlobalVariable *DIDescriptor::getGlobalVariableField(unsigned Elt) const {
 128   if (GV == 0) return 0;
 129
 130   Constant *C = GV->getInitializer();
 131   if (C == 0 || Elt >= C->getNumOperands())
 132     return 0;
 133
 134   C = C->getOperand(Elt);
 135   return dyn_cast<GlobalVariable>(C->stripPointerCasts());
 136 }
 137
 138 //===----------------------------------------------------------------------===//
 139 // Simple Descriptor Constructors and other Methods
 140 //===----------------------------------------------------------------------===//
 141
 142 // Needed by DIVariable::getType().
 143 DIType::DIType(GlobalVariable *gv) : DIDescriptor(gv) {
 144   if (!gv) return;
 145   unsigned tag = getTag();
 146   if (tag != dwarf::DW_TAG_base_type && !DIDerivedType::isDerivedType(tag) &&
 147       !DICompositeType::isCompositeType(tag))
 148     GV = 0;
 149 }
 150
 151 /// isDerivedType - Return true if the specified tag is legal for
 152 /// DIDerivedType.
 153 bool DIType::isDerivedType(unsigned Tag) {
 154   switch (Tag) {
 155   case dwarf::DW_TAG_typedef:
 156   case dwarf::DW_TAG_pointer_type:
 157   case dwarf::DW_TAG_reference_type:
 158   case dwarf::DW_TAG_const_type:
 159   case dwarf::DW_TAG_volatile_type:
 160   case dwarf::DW_TAG_restrict_type:
 161   case dwarf::DW_TAG_member:
 162   case dwarf::DW_TAG_inheritance:
 163     return true;
 164   default:
 165     // FIXME: Even though it doesn't make sense, CompositeTypes are current
 166     // modelled as DerivedTypes, this should return true for them as well.
 167     return false;
 168   }
 169 }
 170
 171 /// isCompositeType - Return true if the specified tag is legal for
 172 /// DICompositeType.
 173 bool DIType::isCompositeType(unsigned TAG) {
 174   switch (TAG) {
 175   case dwarf::DW_TAG_array_type:
 176   case dwarf::DW_TAG_structure_type:
 177   case dwarf::DW_TAG_union_type:
 178   case dwarf::DW_TAG_enumeration_type:
 179   case dwarf::DW_TAG_vector_type:
 180   case dwarf::DW_TAG_subroutine_type:
 181   case dwarf::DW_TAG_class_type:
 182     return true;
 183   default:
 184     return false;
 185   }
 186 }
 187
 188 /// isVariable - Return true if the specified tag is legal for DIVariable.
 189 bool DIVariable::isVariable(unsigned Tag) {
 190   switch (Tag) {
 191   case dwarf::DW_TAG_auto_variable:
 192   case dwarf::DW_TAG_arg_variable:
 193   case dwarf::DW_TAG_return_variable:
 194     return true;
 195   default:
 196     return false;
 197   }
 198 }
 199
 200 unsigned DIArray::getNumElements() const {
 201   assert (GV && "Invalid DIArray");
 202   Constant *C = GV->getInitializer();
 203   assert (C && "Invalid DIArray initializer");
 204   return C->getNumOperands();
 205 }
 206
 207 /// Verify - Verify that a compile unit is well formed.
 208 bool DICompileUnit::Verify() const {
 209   if (isNull())
 210     return false;
 211   std::string Res;
 212   if (getFilename(Res).empty())
 213     return false;
 214   // It is possible that directory and produce string is empty.
 215   return true;
 216 }
 217
 218 /// Verify - Verify that a type descriptor is well formed.
 219 bool DIType::Verify() const {
 220   if (isNull())
 221     return false;
 222   if (getContext().isNull())
 223     return false;
 224
 225   DICompileUnit CU = getCompileUnit();
 226   if (!CU.isNull() && !CU.Verify())
 227     return false;
 228   return true;
 229 }
 230
 231 /// Verify - Verify that a composite type descriptor is well formed.
 232 bool DICompositeType::Verify() const {
 233   if (isNull())
 234     return false;
 235   if (getContext().isNull())
 236     return false;
 237
 238   DICompileUnit CU = getCompileUnit();
 239   if (!CU.isNull() && !CU.Verify())
 240     return false;
 241   return true;
 242 }
 243
 244 /// Verify - Verify that a subprogram descriptor is well formed.
 245 bool DISubprogram::Verify() const {
 246   if (isNull())
 247     return false;
 248
 249   if (getContext().isNull())
 250     return false;
 251
 252   DICompileUnit CU = getCompileUnit();
 253   if (!CU.Verify())
 254     return false;
 255
 256   DICompositeType Ty = getType();
 257   if (!Ty.isNull() && !Ty.Verify())
 258     return false;
 259   return true;
 260 }
 261
 262 /// Verify - Verify that a global variable descriptor is well formed.
 263 bool DIGlobalVariable::Verify() const {
 264   if (isNull())
 265     return false;
 266
 267   if (getContext().isNull())
 268     return false;
 269
 270   DICompileUnit CU = getCompileUnit();
 271   if (!CU.isNull() && !CU.Verify())
 272     return false;
 273
 274   DIType Ty = getType();
 275   if (!Ty.Verify())
 276     return false;
 277
 278   if (!getGlobal())
 279     return false;
 280
 281   return true;
 282 }
 283
 284 /// Verify - Verify that a variable descriptor is well formed.
 285 bool DIVariable::Verify() const {
 286   if (isNull())
 287     return false;
 288
 289   if (getContext().isNull())
 290     return false;
 291
 292   DIType Ty = getType();
 293   if (!Ty.Verify())
 294     return false;
 295
 296   return true;
 297 }
 298
 299 /// getOriginalTypeSize - If this type is derived from a base type then
 300 /// return base type size.
 301 uint64_t DIDerivedType::getOriginalTypeSize() const {
 302   if (getTag() != dwarf::DW_TAG_member)
 303     return getSizeInBits();
 304   DIType BT = getTypeDerivedFrom();
 305   if (BT.getTag() != dwarf::DW_TAG_base_type)
 306     return getSizeInBits();
 307   return BT.getSizeInBits();
 308 }
 309
 310 /// describes - Return true if this subprogram provides debugging
 311 /// information for the function F.
 312 bool DISubprogram::describes(const Function *F) {
 313   assert (F && "Invalid function");
 314   std::string Name;
 315   getLinkageName(Name);
 316   if (Name.empty())
 317     getName(Name);
 318   if (!Name.empty() && (strcmp(Name.c_str(), F->getNameStart()) == false))
 319     return true;
 320   return false;
 321 }
 322
 323 //===----------------------------------------------------------------------===//
 324 // DIFactory: Basic Helpers
 325 //===----------------------------------------------------------------------===//
 326
 327 DIFactory::DIFactory(Module &m)
 328   : M(m), StopPointFn(0), FuncStartFn(0), RegionStartFn(0), RegionEndFn(0),
 329     DeclareFn(0) {
 330   EmptyStructPtr = PointerType::getUnqual(StructType::get(NULL, NULL));
 331 }
 332
 333 /// getCastToEmpty - Return this descriptor as a Constant* with type '{}*'.
 334 /// This is only valid when the descriptor is non-null.
 335 Constant *DIFactory::getCastToEmpty(DIDescriptor D) {
 336   if (D.isNull()) return Constant::getNullValue(EmptyStructPtr);
 337   return ConstantExpr::getBitCast(D.getGV(), EmptyStructPtr);
 338 }
 339
 340 Constant *DIFactory::GetTagConstant(unsigned TAG) {
 341   assert((TAG & LLVMDebugVersionMask) == 0 &&
 342          "Tag too large for debug encoding!");
 343   return ConstantInt::get(Type::Int32Ty, TAG | LLVMDebugVersion);
 344 }
 345
 346 Constant *DIFactory::GetStringConstant(const std::string &String) {
 347   // Check string cache for previous edition.
 348   Constant *&Slot = StringCache[String];
 349
 350   // Return Constant if previously defined.
 351   if (Slot) return Slot;
 352
 353   const PointerType *DestTy = PointerType::getUnqual(Type::Int8Ty);
 354
 355   // If empty string then use a sbyte* null instead.
 356   if (String.empty())
 357     return Slot = ConstantPointerNull::get(DestTy);
 358
 359   // Construct string as an llvm constant.
 360   Constant *ConstStr = ConstantArray::get(String);
 361
 362   // Otherwise create and return a new string global.
 363   GlobalVariable *StrGV = new GlobalVariable(ConstStr->getType(), true,
 364                                              GlobalVariable::InternalLinkage,
 365                                              ConstStr, ".str", &M);
 366   StrGV->setSection("llvm.metadata");
 367   return Slot = ConstantExpr::getBitCast(StrGV, DestTy);
 368 }
 369
 370 /// GetOrCreateAnchor - Look up an anchor for the specified tag and name.  If it
 371 /// already exists, return it.  If not, create a new one and return it.
 372 DIAnchor DIFactory::GetOrCreateAnchor(unsigned TAG, const char *Name) {
 373   const Type *EltTy = StructType::get(Type::Int32Ty, Type::Int32Ty, NULL);
 374
 375   // Otherwise, create the global or return it if already in the module.
 376   Constant *C = M.getOrInsertGlobal(Name, EltTy);
 377   assert(isa<GlobalVariable>(C) && "Incorrectly typed anchor?");
 378   GlobalVariable *GV = cast<GlobalVariable>(C);
 379
 380   // If it has an initializer, it is already in the module.
 381   if (GV->hasInitializer())
 382     return SubProgramAnchor = DIAnchor(GV);
 383
 384   GV->setLinkage(GlobalValue::LinkOnceAnyLinkage);
 385   GV->setSection("llvm.metadata");
 386   GV->setConstant(true);
 387   M.addTypeName("llvm.dbg.anchor.type", EltTy);
 388
 389   // Otherwise, set the initializer.
 390   Constant *Elts[] = {
 391     GetTagConstant(dwarf::DW_TAG_anchor),
 392     ConstantInt::get(Type::Int32Ty, TAG)
 393   };
 394
 395   GV->setInitializer(ConstantStruct::get(Elts, 2));
 396   return DIAnchor(GV);
 397 }
 398
 399
 400
 401 //===----------------------------------------------------------------------===//
 402 // DIFactory: Primary Constructors
 403 //===----------------------------------------------------------------------===//
 404
 405 /// GetOrCreateCompileUnitAnchor - Return the anchor for compile units,
 406 /// creating a new one if there isn't already one in the module.
 407 DIAnchor DIFactory::GetOrCreateCompileUnitAnchor() {
 408   // If we already created one, just return it.
 409   if (!CompileUnitAnchor.isNull())
 410     return CompileUnitAnchor;
 411   return CompileUnitAnchor = GetOrCreateAnchor(dwarf::DW_TAG_compile_unit,
 412                                                "llvm.dbg.compile_units");
 413 }
 414
 415 /// GetOrCreateSubprogramAnchor - Return the anchor for subprograms,
 416 /// creating a new one if there isn't already one in the module.
 417 DIAnchor DIFactory::GetOrCreateSubprogramAnchor() {
 418   // If we already created one, just return it.
 419   if (!SubProgramAnchor.isNull())
 420     return SubProgramAnchor;
 421   return SubProgramAnchor = GetOrCreateAnchor(dwarf::DW_TAG_subprogram,
 422                                               "llvm.dbg.subprograms");
 423 }
 424
 425 /// GetOrCreateGlobalVariableAnchor - Return the anchor for globals,
 426 /// creating a new one if there isn't already one in the module.
 427 DIAnchor DIFactory::GetOrCreateGlobalVariableAnchor() {
 428   // If we already created one, just return it.
 429   if (!GlobalVariableAnchor.isNull())
 430     return GlobalVariableAnchor;
 431   return GlobalVariableAnchor = GetOrCreateAnchor(dwarf::DW_TAG_variable,
 432                                                   "llvm.dbg.global_variables");
 433 }
 434
 435 /// GetOrCreateArray - Create an descriptor for an array of descriptors.
 436 /// This implicitly uniques the arrays created.
 437 DIArray DIFactory::GetOrCreateArray(DIDescriptor *Tys, unsigned NumTys) {
 438   SmallVector<Constant*, 16> Elts;
 439
 440   for (unsigned i = 0; i != NumTys; ++i)
 441     Elts.push_back(getCastToEmpty(Tys[i]));
 442
 443   Constant *Init = ConstantArray::get(ArrayType::get(EmptyStructPtr,
 444                                                      Elts.size()),
 445                                       &Elts[0], Elts.size());
 446   // If we already have this array, just return the uniqued version.
 447   DIDescriptor &Entry = SimpleConstantCache[Init];
 448   if (!Entry.isNull()) return DIArray(Entry.getGV());
 449
 450   GlobalVariable *GV = new GlobalVariable(Init->getType(), true,
 451                                           GlobalValue::InternalLinkage,
 452                                           Init, "llvm.dbg.array", &M);
 453   GV->setSection("llvm.metadata");
 454   Entry = DIDescriptor(GV);
 455   return DIArray(GV);
 456 }
 457
 458 /// GetOrCreateSubrange - Create a descriptor for a value range.  This
 459 /// implicitly uniques the values returned.
 460 DISubrange DIFactory::GetOrCreateSubrange(int64_t Lo, int64_t Hi) {
 461   Constant *Elts[] = {
 462     GetTagConstant(dwarf::DW_TAG_subrange_type),
 463     ConstantInt::get(Type::Int64Ty, Lo),
 464     ConstantInt::get(Type::Int64Ty, Hi)
 465   };
 466
 467   Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0]));
 468
 469   // If we already have this range, just return the uniqued version.
 470   DIDescriptor &Entry = SimpleConstantCache[Init];
 471   if (!Entry.isNull()) return DISubrange(Entry.getGV());
 472
 473   M.addTypeName("llvm.dbg.subrange.type", Init->getType());
 474
 475   GlobalVariable *GV = new GlobalVariable(Init->getType(), true,
 476                                           GlobalValue::InternalLinkage,
 477                                           Init, "llvm.dbg.subrange", &M);
 478   GV->setSection("llvm.metadata");
 479   Entry = DIDescriptor(GV);
 480   return DISubrange(GV);
 481 }
 482
 483
 484
 485 /// CreateCompileUnit - Create a new descriptor for the specified compile
 486 /// unit.  Note that this does not unique compile units within the module.
 487 DICompileUnit DIFactory::CreateCompileUnit(unsigned LangID,
 488                                            const std::string &Filename,
 489                                            const std::string &Directory,
 490                                            const std::string &Producer,
 491                                            bool isMain,
 492                                            bool isOptimized,
 493                                            const char *Flags,
 494                                            unsigned RunTimeVer) {
 495   Constant *Elts[] = {
 496     GetTagConstant(dwarf::DW_TAG_compile_unit),
 497     getCastToEmpty(GetOrCreateCompileUnitAnchor()),
 498     ConstantInt::get(Type::Int32Ty, LangID),
 499     GetStringConstant(Filename),
 500     GetStringConstant(Directory),
 501     GetStringConstant(Producer),
 502     ConstantInt::get(Type::Int1Ty, isMain),
 503     ConstantInt::get(Type::Int1Ty, isOptimized),
 504     GetStringConstant(Flags),
 505     ConstantInt::get(Type::Int32Ty, RunTimeVer)
 506   };
 507
 508   Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0]));
 509
 510   M.addTypeName("llvm.dbg.compile_unit.type", Init->getType());
 511   GlobalVariable *GV = new GlobalVariable(Init->getType(), true,
 512                                           GlobalValue::InternalLinkage,
 513                                           Init, "llvm.dbg.compile_unit", &M);
 514   GV->setSection("llvm.metadata");
 515   return DICompileUnit(GV);
 516 }
 517
 518 /// CreateEnumerator - Create a single enumerator value.
 519 DIEnumerator DIFactory::CreateEnumerator(const std::string &Name, uint64_t Val){
 520   Constant *Elts[] = {
 521     GetTagConstant(dwarf::DW_TAG_enumerator),
 522     GetStringConstant(Name),
 523     ConstantInt::get(Type::Int64Ty, Val)
 524   };
 525
 526   Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0]));
 527
 528   M.addTypeName("llvm.dbg.enumerator.type", Init->getType());
 529   GlobalVariable *GV = new GlobalVariable(Init->getType(), true,
 530                                           GlobalValue::InternalLinkage,
 531                                           Init, "llvm.dbg.enumerator", &M);
 532   GV->setSection("llvm.metadata");
 533   return DIEnumerator(GV);
 534 }
 535
 536
 537 /// CreateBasicType - Create a basic type like int, float, etc.
 538 DIBasicType DIFactory::CreateBasicType(DIDescriptor Context,
 539                                       const std::string &Name,
 540                                        DICompileUnit CompileUnit,
 541                                        unsigned LineNumber,
 542                                        uint64_t SizeInBits,
 543                                        uint64_t AlignInBits,
 544                                        uint64_t OffsetInBits, unsigned Flags,
 545                                        unsigned Encoding) {
 546   Constant *Elts[] = {
 547     GetTagConstant(dwarf::DW_TAG_base_type),
 548     getCastToEmpty(Context),
 549     GetStringConstant(Name),
 550     getCastToEmpty(CompileUnit),
 551     ConstantInt::get(Type::Int32Ty, LineNumber),
 552     ConstantInt::get(Type::Int64Ty, SizeInBits),
 553     ConstantInt::get(Type::Int64Ty, AlignInBits),
 554     ConstantInt::get(Type::Int64Ty, OffsetInBits),
 555     ConstantInt::get(Type::Int32Ty, Flags),
 556     ConstantInt::get(Type::Int32Ty, Encoding)
 557   };
 558
 559   Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0]));
 560
 561   M.addTypeName("llvm.dbg.basictype.type", Init->getType());
 562   GlobalVariable *GV = new GlobalVariable(Init->getType(), true,
 563                                           GlobalValue::InternalLinkage,
 564                                           Init, "llvm.dbg.basictype", &M);
 565   GV->setSection("llvm.metadata");
 566   return DIBasicType(GV);
 567 }
 568
 569 /// CreateDerivedType - Create a derived type like const qualified type,
 570 /// pointer, typedef, etc.
 571 DIDerivedType DIFactory::CreateDerivedType(unsigned Tag,
 572                                            DIDescriptor Context,
 573                                            const std::string &Name,
 574                                            DICompileUnit CompileUnit,
 575                                            unsigned LineNumber,
 576                                            uint64_t SizeInBits,
 577                                            uint64_t AlignInBits,
 578                                            uint64_t OffsetInBits,
 579                                            unsigned Flags,
 580                                            DIType DerivedFrom) {
 581   Constant *Elts[] = {
 582     GetTagConstant(Tag),
 583     getCastToEmpty(Context),
 584     GetStringConstant(Name),
 585     getCastToEmpty(CompileUnit),
 586     ConstantInt::get(Type::Int32Ty, LineNumber),
 587     ConstantInt::get(Type::Int64Ty, SizeInBits),
 588     ConstantInt::get(Type::Int64Ty, AlignInBits),
 589     ConstantInt::get(Type::Int64Ty, OffsetInBits),
 590     ConstantInt::get(Type::Int32Ty, Flags),
 591     getCastToEmpty(DerivedFrom)
 592   };
 593
 594   Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0]));
 595
 596   M.addTypeName("llvm.dbg.derivedtype.type", Init->getType());
 597   GlobalVariable *GV = new GlobalVariable(Init->getType(), true,
 598                                           GlobalValue::InternalLinkage,
 599                                           Init, "llvm.dbg.derivedtype", &M);
 600   GV->setSection("llvm.metadata");
 601   return DIDerivedType(GV);
 602 }
 603
 604 /// CreateCompositeType - Create a composite type like array, struct, etc.
 605 DICompositeType DIFactory::CreateCompositeType(unsigned Tag,
 606                                                DIDescriptor Context,
 607                                                const std::string &Name,
 608                                                DICompileUnit CompileUnit,
 609                                                unsigned LineNumber,
 610                                                uint64_t SizeInBits,
 611                                                uint64_t AlignInBits,
 612                                                uint64_t OffsetInBits,
 613                                                unsigned Flags,
 614                                                DIType DerivedFrom,
 615                                                DIArray Elements,
 616                                                unsigned RuntimeLang) {
 617
 618   Constant *Elts[] = {
 619     GetTagConstant(Tag),
 620     getCastToEmpty(Context),
 621     GetStringConstant(Name),
 622     getCastToEmpty(CompileUnit),
 623     ConstantInt::get(Type::Int32Ty, LineNumber),
 624     ConstantInt::get(Type::Int64Ty, SizeInBits),
 625     ConstantInt::get(Type::Int64Ty, AlignInBits),
 626     ConstantInt::get(Type::Int64Ty, OffsetInBits),
 627     ConstantInt::get(Type::Int32Ty, Flags),
 628     getCastToEmpty(DerivedFrom),
 629     getCastToEmpty(Elements),
 630     ConstantInt::get(Type::Int32Ty, RuntimeLang)
 631   };
 632
 633   Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0]));
 634
 635   M.addTypeName("llvm.dbg.composite.type", Init->getType());
 636   GlobalVariable *GV = new GlobalVariable(Init->getType(), true,
 637                                           GlobalValue::InternalLinkage,
 638                                           Init, "llvm.dbg.composite", &M);
 639   GV->setSection("llvm.metadata");
 640   return DICompositeType(GV);
 641 }
 642
 643
 644 /// CreateSubprogram - Create a new descriptor for the specified subprogram.
 645 /// See comments in DISubprogram for descriptions of these fields.  This
 646 /// method does not unique the generated descriptors.
 647 DISubprogram DIFactory::CreateSubprogram(DIDescriptor Context,
 648                                          const std::string &Name,
 649                                          const std::string &DisplayName,
 650                                          const std::string &LinkageName,
 651                                          DICompileUnit CompileUnit,
 652                                          unsigned LineNo, DIType Type,
 653                                          bool isLocalToUnit,
 654                                          bool isDefinition) {
 655
 656   Constant *Elts[] = {
 657     GetTagConstant(dwarf::DW_TAG_subprogram),
 658     getCastToEmpty(GetOrCreateSubprogramAnchor()),
 659     getCastToEmpty(Context),
 660     GetStringConstant(Name),
 661     GetStringConstant(DisplayName),
 662     GetStringConstant(LinkageName),
 663     getCastToEmpty(CompileUnit),
 664     ConstantInt::get(Type::Int32Ty, LineNo),
 665     getCastToEmpty(Type),
 666     ConstantInt::get(Type::Int1Ty, isLocalToUnit),
 667     ConstantInt::get(Type::Int1Ty, isDefinition)
 668   };
 669
 670   Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0]));
 671
 672   M.addTypeName("llvm.dbg.subprogram.type", Init->getType());
 673   GlobalVariable *GV = new GlobalVariable(Init->getType(), true,
 674                                           GlobalValue::InternalLinkage,
 675                                           Init, "llvm.dbg.subprogram", &M);
 676   GV->setSection("llvm.metadata");
 677   return DISubprogram(GV);
 678 }
 679
 680 /// CreateGlobalVariable - Create a new descriptor for the specified global.
 681 DIGlobalVariable
 682 DIFactory::CreateGlobalVariable(DIDescriptor Context, const std::string &Name,
 683                                 const std::string &DisplayName,
 684                                 const std::string &LinkageName,
 685                                 DICompileUnit CompileUnit,
 686                                 unsigned LineNo, DIType Type,bool isLocalToUnit,
 687                                 bool isDefinition, llvm::GlobalVariable *Val) {
 688   Constant *Elts[] = {
 689     GetTagConstant(dwarf::DW_TAG_variable),
 690     getCastToEmpty(GetOrCreateGlobalVariableAnchor()),
 691     getCastToEmpty(Context),
 692     GetStringConstant(Name),
 693     GetStringConstant(DisplayName),
 694     GetStringConstant(LinkageName),
 695     getCastToEmpty(CompileUnit),
 696     ConstantInt::get(Type::Int32Ty, LineNo),
 697     getCastToEmpty(Type),
 698     ConstantInt::get(Type::Int1Ty, isLocalToUnit),
 699     ConstantInt::get(Type::Int1Ty, isDefinition),
 700     ConstantExpr::getBitCast(Val, EmptyStructPtr)
 701   };
 702
 703   Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0]));
 704
 705   M.addTypeName("llvm.dbg.global_variable.type", Init->getType());
 706   GlobalVariable *GV = new GlobalVariable(Init->getType(), true,
 707                                           GlobalValue::InternalLinkage,
 708                                           Init, "llvm.dbg.global_variable", &M);
 709   GV->setSection("llvm.metadata");
 710   return DIGlobalVariable(GV);
 711 }
 712
 713
 714 /// CreateVariable - Create a new descriptor for the specified variable.
 715 DIVariable DIFactory::CreateVariable(unsigned Tag, DIDescriptor Context,
 716                                      const std::string &Name,
 717                                      DICompileUnit CompileUnit, unsigned LineNo,
 718                                      DIType Type) {
 719   Constant *Elts[] = {
 720     GetTagConstant(Tag),
 721     getCastToEmpty(Context),
 722     GetStringConstant(Name),
 723     getCastToEmpty(CompileUnit),
 724     ConstantInt::get(Type::Int32Ty, LineNo),
 725     getCastToEmpty(Type)
 726   };
 727
 728   Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0]));
 729
 730   M.addTypeName("llvm.dbg.variable.type", Init->getType());
 731   GlobalVariable *GV = new GlobalVariable(Init->getType(), true,
 732                                           GlobalValue::InternalLinkage,
 733                                           Init, "llvm.dbg.variable", &M);
 734   GV->setSection("llvm.metadata");
 735   return DIVariable(GV);
 736 }
 737
 738
 739 /// CreateBlock - This creates a descriptor for a lexical block with the
 740 /// specified parent context.
 741 DIBlock DIFactory::CreateBlock(DIDescriptor Context) {
 742   Constant *Elts[] = {
 743     GetTagConstant(dwarf::DW_TAG_lexical_block),
 744     getCastToEmpty(Context)
 745   };
 746
 747   Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0]));
 748
 749   M.addTypeName("llvm.dbg.block.type", Init->getType());
 750   GlobalVariable *GV = new GlobalVariable(Init->getType(), true,
 751                                           GlobalValue::InternalLinkage,
 752                                           Init, "llvm.dbg.block", &M);
 753   GV->setSection("llvm.metadata");
 754   return DIBlock(GV);
 755 }
 756
 757
 758 //===----------------------------------------------------------------------===//
 759 // DIFactory: Routines for inserting code into a function
 760 //===----------------------------------------------------------------------===//
 761
 762 /// InsertStopPoint - Create a new llvm.dbg.stoppoint intrinsic invocation,
 763 /// inserting it at the end of the specified basic block.
 764 void DIFactory::InsertStopPoint(DICompileUnit CU, unsigned LineNo,
 765                                 unsigned ColNo, BasicBlock *BB) {
 766
 767   // Lazily construct llvm.dbg.stoppoint function.
 768   if (!StopPointFn)
 769     StopPointFn = llvm::Intrinsic::getDeclaration(&M,
 770                                               llvm::Intrinsic::dbg_stoppoint);
 771
 772   // Invoke llvm.dbg.stoppoint
 773   Value *Args[] = {
 774     llvm::ConstantInt::get(llvm::Type::Int32Ty, LineNo),
 775     llvm::ConstantInt::get(llvm::Type::Int32Ty, ColNo),
 776     getCastToEmpty(CU)
 777   };
 778   CallInst::Create(StopPointFn, Args, Args+3, "", BB);
 779 }
 780
 781 /// InsertSubprogramStart - Create a new llvm.dbg.func.start intrinsic to
 782 /// mark the start of the specified subprogram.
 783 void DIFactory::InsertSubprogramStart(DISubprogram SP, BasicBlock *BB) {
 784   // Lazily construct llvm.dbg.func.start.
 785   if (!FuncStartFn)
 786     FuncStartFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_func_start);
 787
 788   // Call llvm.dbg.func.start which also implicitly sets a stoppoint.
 789   CallInst::Create(FuncStartFn, getCastToEmpty(SP), "", BB);
 790 }
 791
 792 /// InsertRegionStart - Insert a new llvm.dbg.region.start intrinsic call to
 793 /// mark the start of a region for the specified scoping descriptor.
 794 void DIFactory::InsertRegionStart(DIDescriptor D, BasicBlock *BB) {
 795   // Lazily construct llvm.dbg.region.start function.
 796   if (!RegionStartFn)
 797     RegionStartFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_region_start);
 798
 799   // Call llvm.dbg.func.start.
 800   CallInst::Create(RegionStartFn, getCastToEmpty(D), "", BB);
 801 }
 802
 803 /// InsertRegionEnd - Insert a new llvm.dbg.region.end intrinsic call to
 804 /// mark the end of a region for the specified scoping descriptor.
 805 void DIFactory::InsertRegionEnd(DIDescriptor D, BasicBlock *BB) {
 806   // Lazily construct llvm.dbg.region.end function.
 807   if (!RegionEndFn)
 808     RegionEndFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_region_end);
 809
 810   // Call llvm.dbg.region.end.
 811   CallInst::Create(RegionEndFn, getCastToEmpty(D), "", BB);
 812 }
 813
 814 /// InsertDeclare - Insert a new llvm.dbg.declare intrinsic call.
 815 void DIFactory::InsertDeclare(Value *Storage, DIVariable D, BasicBlock *BB) {
 816   // Cast the storage to a {}* for the call to llvm.dbg.declare.
 817   Storage = new BitCastInst(Storage, EmptyStructPtr, "", BB);
 818
 819   if (!DeclareFn)
 820     DeclareFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_declare);
 821
 822   Value *Args[] = { Storage, getCastToEmpty(D) };
 823   CallInst::Create(DeclareFn, Args, Args+2, "", BB);
 824 }
 825
 826 namespace llvm {
 827   /// findStopPoint - Find the stoppoint coressponding to this instruction, that
 828   /// is the stoppoint that dominates this instruction.
 829   const DbgStopPointInst *findStopPoint(const Instruction *Inst) {
 830     if (const DbgStopPointInst *DSI = dyn_cast<DbgStopPointInst>(Inst))
 831       return DSI;
 832
 833     const BasicBlock *BB = Inst->getParent();
 834     BasicBlock::const_iterator I = Inst, B;
 835     while (BB) {
 836       B = BB->begin();
 837
 838       // A BB consisting only of a terminator can't have a stoppoint.
 839       while (I != B) {
 840         --I;
 841         if (const DbgStopPointInst *DSI = dyn_cast<DbgStopPointInst>(I))
 842           return DSI;
 843       }
 844
 845       // This BB didn't have a stoppoint: if there is only one predecessor, look
 846       // for a stoppoint there. We could use getIDom(), but that would require
 847       // dominator info.
 848       BB = I->getParent()->getUniquePredecessor();
 849       if (BB)
 850         I = BB->getTerminator();
 851     }
 852
 853     return 0;
 854   }
 855
 856   /// findBBStopPoint - Find the stoppoint corresponding to first real
 857   /// (non-debug intrinsic) instruction in this Basic Block, and return the
 858   /// stoppoint for it.
 859   const DbgStopPointInst *findBBStopPoint(const BasicBlock *BB) {
 860     for(BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I != E; ++I)
 861       if (const DbgStopPointInst *DSI = dyn_cast<DbgStopPointInst>(I))
 862         return DSI;
 863
 864     // Fallback to looking for stoppoint of unique predecessor. Useful if this
 865     // BB contains no stoppoints, but unique predecessor does.
 866     BB = BB->getUniquePredecessor();
 867     if (BB)
 868       return findStopPoint(BB->getTerminator());
 869
 870     return 0;
 871   }
 872
 873   Value *findDbgGlobalDeclare(GlobalVariable *V) {
 874     const Module *M = V->getParent();
 875     const Type *Ty = M->getTypeByName("llvm.dbg.global_variable.type");
 876     if (!Ty) return 0;
 877
 878     Ty = PointerType::get(Ty, 0);
 879
 880     Value *Val = V->stripPointerCasts();
 881     for (Value::use_iterator I = Val->use_begin(), E = Val->use_end();
 882          I != E; ++I) {
 883       if (ConstantExpr *CE = dyn_cast<ConstantExpr>(I)) {
 884         if (CE->getOpcode() == Instruction::BitCast) {
 885           Value *VV = CE;
 886
 887           while (VV->hasOneUse())
 888             VV = *VV->use_begin();
 889
 890           if (VV->getType() == Ty)
 891             return VV;
 892         }
 893       }
 894     }
 895
 896     if (Val->getType() == Ty)
 897       return Val;
 898
 899     return 0;
 900   }
 901
 902   /// Finds the llvm.dbg.declare intrinsic corresponding to this value if any.
 903   /// It looks through pointer casts too.
 904   const DbgDeclareInst *findDbgDeclare(const Value *V, bool stripCasts) {
 905     if (stripCasts) {
 906       V = V->stripPointerCasts();
 907
 908       // Look for the bitcast.
 909       for (Value::use_const_iterator I = V->use_begin(), E =V->use_end();
 910             I != E; ++I)
 911         if (isa<BitCastInst>(I))
 912           return findDbgDeclare(*I, false);
 913
 914       return 0;
 915     }
 916
 917     // Find llvm.dbg.declare among uses of the instruction.
 918     for (Value::use_const_iterator I = V->use_begin(), E =V->use_end();
 919           I != E; ++I)
 920       if (const DbgDeclareInst *DDI = dyn_cast<DbgDeclareInst>(I))
 921         return DDI;
 922
 923     return 0;
 924   }
 925
 926   bool getLocationInfo(const Value *V, std::string &DisplayName,
 927                        std::string &Type, unsigned &LineNo, std::string &File,
 928                        std::string &Dir) {
 929     DICompileUnit Unit;
 930     DIType TypeD;
 931
 932     if (GlobalVariable *GV = dyn_cast<GlobalVariable>(const_cast<Value*>(V))) {
 933       Value *DIGV = findDbgGlobalDeclare(GV);
 934       if (!DIGV) return false;
 935       DIGlobalVariable Var(cast<GlobalVariable>(DIGV));
 936
 937       Var.getDisplayName(DisplayName);
 938       LineNo = Var.getLineNumber();
 939       Unit = Var.getCompileUnit();
 940       TypeD = Var.getType();
 941     } else {
 942       const DbgDeclareInst *DDI = findDbgDeclare(V);
 943       if (!DDI) return false;
 944       DIVariable Var(cast<GlobalVariable>(DDI->getVariable()));
 945
 946       Var.getName(DisplayName);
 947       LineNo = Var.getLineNumber();
 948       Unit = Var.getCompileUnit();
 949       TypeD = Var.getType();
 950     }
 951
 952     TypeD.getName(Type);
 953     Unit.getFilename(File);
 954     Unit.getDirectory(Dir);
 955     return true;
 956   }
 957 }
 958
 959 /// dump - Print descriptor.
 960 void DIDescriptor::dump() const {
 961   cerr << "[" << dwarf::TagString(getTag()) << "] ";
 962   cerr << std::hex << "[GV:" << GV << "]" << std::dec;
 963 }
 964
 965 /// dump - Print compile unit.
 966 void DICompileUnit::dump() const {
 967   if (getLanguage())
 968     cerr << " [" << dwarf::LanguageString(getLanguage()) << "] ";
 969
 970   std::string Res1, Res2;
 971   cerr << " [" << getDirectory(Res1) << "/" << getFilename(Res2) << " ]";
 972 }
 973
 974 /// dump - Print type.
 975 void DIType::dump() const {
 976   if (isNull()) return;
 977
 978   std::string Res;
 979   if (!getName(Res).empty())
 980     cerr << " [" << Res << "] ";
 981
 982   unsigned Tag = getTag();
 983   cerr << " [" << dwarf::TagString(Tag) << "] ";
 984
 985   // TODO : Print context
 986   getCompileUnit().dump();
 987   cerr << " ["
 988        << getLineNumber() << ", "
 989        << getSizeInBits() << ", "
 990        << getAlignInBits() << ", "
 991        << getOffsetInBits()
 992        << "] ";
 993
 994   if (isPrivate())
 995     cerr << " [private] ";
 996   else if (isProtected())
 997     cerr << " [protected] ";
 998
 999   if (isForwardDecl())
1000     cerr << " [fwd] ";
1001
1002   if (isBasicType(Tag))
1003     DIBasicType(GV).dump();
1004   else if (isDerivedType(Tag))
1005     DIDerivedType(GV).dump();
1006   else if (isCompositeType(Tag))
1007     DICompositeType(GV).dump();
1008   else {
1009     cerr << "Invalid DIType\n";
1010     return;
1011   }
1012
1013   cerr << "\n";
1014 }
1015
1016 /// dump - Print basic type.
1017 void DIBasicType::dump() const {
1018   cerr << " [" << dwarf::AttributeEncodingString(getEncoding()) << "] ";
1019 }
1020
1021 /// dump - Print derived type.
1022 void DIDerivedType::dump() const {
1023   cerr << "\n\t Derived From: "; getTypeDerivedFrom().dump();
1024 }
1025
1026 /// dump - Print composite type.
1027 void DICompositeType::dump() const {
1028   DIArray A = getTypeArray();
1029   if (A.isNull())
1030     return;
1031   cerr << " [" << A.getNumElements() << " elements]";
1032 }
1033
1034 /// dump - Print global.
1035 void DIGlobal::dump() const {
1036   std::string Res;
1037   if (!getName(Res).empty())
1038     cerr << " [" << Res << "] ";
1039
1040   unsigned Tag = getTag();
1041   cerr << " [" << dwarf::TagString(Tag) << "] ";
1042
1043   // TODO : Print context
1044   getCompileUnit().dump();
1045   cerr << " [" << getLineNumber() << "] ";
1046
1047   if (isLocalToUnit())
1048     cerr << " [local] ";
1049
1050   if (isDefinition())
1051     cerr << " [def] ";
1052
1053   if (isGlobalVariable(Tag))
1054     DIGlobalVariable(GV).dump();
1055
1056   cerr << "\n";
1057 }
1058
1059 /// dump - Print subprogram.
1060 void DISubprogram::dump() const {
1061   DIGlobal::dump();
1062 }
1063
1064 /// dump - Print global variable.
1065 void DIGlobalVariable::dump() const {
1066   cerr << " ["; getGlobal()->dump(); cerr << "] ";
1067 }
1068
1069 /// dump - Print variable.
1070 void DIVariable::dump() const {
1071   std::string Res;
1072   if (!getName(Res).empty())
1073     cerr << " [" << Res << "] ";
1074
1075   getCompileUnit().dump();
1076   cerr << " [" << getLineNumber() << "] ";
1077   getType().dump();
1078   cerr << "\n";
1079 }