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 using namespace llvm;
  25
  26 //===----------------------------------------------------------------------===//
  27 // DIDescriptor
  28 //===----------------------------------------------------------------------===//
  29
  30 DIDescriptor::DIDescriptor(GlobalVariable *gv, unsigned RequiredTag) {
  31   GV = gv;
  32
  33   // If this is non-null, check to see if the Tag matches.  If not, set to null.
  34   if (GV && getTag() != RequiredTag)
  35     GV = 0;
  36 }
  37
  38
  39 std::string DIDescriptor::getStringField(unsigned Elt) const {
  40   if (GV == 0) return "";
  41   Constant *C = GV->getInitializer();
  42   if (C == 0 || Elt >= C->getNumOperands())
  43     return "";
  44
  45   std::string Result;
  46   // Fills in the string if it succeeds
  47   if (!GetConstantStringInfo(C->getOperand(Elt), Result))
  48     Result.clear();
  49   return Result;
  50 }
  51
  52 uint64_t DIDescriptor::getUInt64Field(unsigned Elt) const {
  53   if (GV == 0) return 0;
  54   Constant *C = GV->getInitializer();
  55   if (C == 0 || Elt >= C->getNumOperands())
  56     return 0;
  57   if (ConstantInt *CI = dyn_cast<ConstantInt>(C->getOperand(Elt)))
  58     return CI->getZExtValue();
  59   return 0;
  60 }
  61
  62
  63 DIDescriptor DIDescriptor::getDescriptorField(unsigned Elt) const {
  64   if (GV == 0) return DIDescriptor();
  65   Constant *C = GV->getInitializer();
  66   if (C == 0 || Elt >= C->getNumOperands())
  67     return DIDescriptor();
  68   C = C->getOperand(Elt);
  69   return DIDescriptor(dyn_cast<GlobalVariable>(C->stripPointerCasts()));
  70 }
  71
  72 GlobalVariable *DIDescriptor::getGlobalVariableField(unsigned Elt) const {
  73   if (GV == 0) return 0;
  74   Constant *C = GV->getInitializer();
  75   if (C == 0 || Elt >= C->getNumOperands())
  76     return 0;
  77   C = C->getOperand(Elt);
  78
  79   return dyn_cast<GlobalVariable>(C->stripPointerCasts());
  80 }
  81
  82
  83
  84 //===----------------------------------------------------------------------===//
  85 // Simple Descriptor Constructors and other Methods
  86 //===----------------------------------------------------------------------===//
  87
  88 DIAnchor::DIAnchor(GlobalVariable *GV)
  89   : DIDescriptor(GV, dwarf::DW_TAG_anchor) {}
  90 DIEnumerator::DIEnumerator(GlobalVariable *GV)
  91   : DIDescriptor(GV, dwarf::DW_TAG_enumerator) {}
  92 DISubrange::DISubrange(GlobalVariable *GV)
  93   : DIDescriptor(GV, dwarf::DW_TAG_subrange_type) {}
  94 DICompileUnit::DICompileUnit(GlobalVariable *GV)
  95   : DIDescriptor(GV, dwarf::DW_TAG_compile_unit) {}
  96 DIBasicType::DIBasicType(GlobalVariable *GV)
  97   : DIType(GV, dwarf::DW_TAG_base_type) {}
  98 DISubprogram::DISubprogram(GlobalVariable *GV)
  99   : DIGlobal(GV, dwarf::DW_TAG_subprogram) {}
 100 DIGlobalVariable::DIGlobalVariable(GlobalVariable *GV)
 101   : DIGlobal(GV, dwarf::DW_TAG_variable) {}
 102 DIBlock::DIBlock(GlobalVariable *GV)
 103   : DIDescriptor(GV, dwarf::DW_TAG_lexical_block) {}
 104 // needed by DIVariable::getType()
 105 DIType::DIType(GlobalVariable *gv) : DIDescriptor(gv) {
 106   if (!gv) return;
 107   unsigned tag = getTag();
 108   if (tag != dwarf::DW_TAG_base_type && !DIDerivedType::isDerivedType(tag) &&
 109       !DICompositeType::isCompositeType(tag))
 110     GV = 0;
 111 }
 112
 113 /// isDerivedType - Return true if the specified tag is legal for
 114 /// DIDerivedType.
 115 bool DIDerivedType::isDerivedType(unsigned Tag) {
 116   switch (Tag) {
 117   case dwarf::DW_TAG_typedef:
 118   case dwarf::DW_TAG_pointer_type:
 119   case dwarf::DW_TAG_reference_type:
 120   case dwarf::DW_TAG_const_type:
 121   case dwarf::DW_TAG_volatile_type:
 122   case dwarf::DW_TAG_restrict_type:
 123   case dwarf::DW_TAG_member:
 124   case dwarf::DW_TAG_inheritance:
 125     return true;
 126   default:
 127     // FIXME: Even though it doesn't make sense, CompositeTypes are current
 128     // modelled as DerivedTypes, this should return true for them as well.
 129     return false;
 130   }
 131 }
 132
 133 DIDerivedType::DIDerivedType(GlobalVariable *GV) : DIType(GV, true, true) {
 134   if (GV && !isDerivedType(getTag()))
 135     GV = 0;
 136 }
 137
 138 /// isCompositeType - Return true if the specified tag is legal for
 139 /// DICompositeType.
 140 bool DICompositeType::isCompositeType(unsigned TAG) {
 141   switch (TAG) {
 142   case dwarf::DW_TAG_array_type:
 143   case dwarf::DW_TAG_structure_type:
 144   case dwarf::DW_TAG_union_type:
 145   case dwarf::DW_TAG_enumeration_type:
 146   case dwarf::DW_TAG_vector_type:
 147   case dwarf::DW_TAG_subroutine_type:
 148     return true;
 149   default:
 150     return false;
 151   }
 152 }
 153
 154 DICompositeType::DICompositeType(GlobalVariable *GV)
 155   : DIDerivedType(GV, true, true) {
 156   if (GV && !isCompositeType(getTag()))
 157     GV = 0;
 158 }
 159
 160 /// isVariable - Return true if the specified tag is legal for DIVariable.
 161 bool DIVariable::isVariable(unsigned Tag) {
 162   switch (Tag) {
 163   case dwarf::DW_TAG_auto_variable:
 164   case dwarf::DW_TAG_arg_variable:
 165   case dwarf::DW_TAG_return_variable:
 166     return true;
 167   default:
 168     return false;
 169   }
 170 }
 171
 172 DIVariable::DIVariable(GlobalVariable *GV) : DIDescriptor(GV) {
 173   if (GV && !isVariable(getTag()))
 174     GV = 0;
 175 }
 176
 177 unsigned DIArray::getNumElements() const {
 178   assert (GV && "Invalid DIArray");
 179   Constant *C = GV->getInitializer();
 180   assert (C && "Invalid DIArray initializer");
 181   return C->getNumOperands();
 182 }
 183
 184 /// isSubrange - Return true if the specified tag is legal for DISubrange.
 185 bool DISubrange::isSubrange(unsigned Tag) {
 186   return Tag == dwarf::DW_TAG_subrange_type;
 187 }
 188
 189 //===----------------------------------------------------------------------===//
 190 // DIFactory: Basic Helpers
 191 //===----------------------------------------------------------------------===//
 192
 193 DIFactory::DIFactory(Module &m) : M(m) {
 194   StopPointFn = FuncStartFn = RegionStartFn = RegionEndFn = DeclareFn = 0;
 195   EmptyStructPtr = PointerType::getUnqual(StructType::get(NULL, NULL));
 196 }
 197
 198 /// getCastToEmpty - Return this descriptor as a Constant* with type '{}*'.
 199 /// This is only valid when the descriptor is non-null.
 200 Constant *DIFactory::getCastToEmpty(DIDescriptor D) {
 201   if (D.isNull()) return Constant::getNullValue(EmptyStructPtr);
 202   return ConstantExpr::getBitCast(D.getGV(), EmptyStructPtr);
 203 }
 204
 205 Constant *DIFactory::GetTagConstant(unsigned TAG) {
 206   assert((TAG & DIDescriptor::VersionMask) == 0 &&
 207          "Tag too large for debug encoding!");
 208   return ConstantInt::get(Type::Int32Ty, TAG | DIDescriptor::Version7);
 209 }
 210
 211 Constant *DIFactory::GetStringConstant(const std::string &String) {
 212   // Check string cache for previous edition.
 213   Constant *&Slot = StringCache[String];
 214
 215   // Return Constant if previously defined.
 216   if (Slot) return Slot;
 217
 218   const PointerType *DestTy = PointerType::getUnqual(Type::Int8Ty);
 219
 220   // If empty string then use a sbyte* null instead.
 221   if (String.empty())
 222     return Slot = ConstantPointerNull::get(DestTy);
 223
 224   // Construct string as an llvm constant.
 225   Constant *ConstStr = ConstantArray::get(String);
 226
 227   // Otherwise create and return a new string global.
 228   GlobalVariable *StrGV = new GlobalVariable(ConstStr->getType(), true,
 229                                              GlobalVariable::InternalLinkage,
 230                                              ConstStr, ".str", &M);
 231   StrGV->setSection("llvm.metadata");
 232   return Slot = ConstantExpr::getBitCast(StrGV, DestTy);
 233 }
 234
 235 /// GetOrCreateAnchor - Look up an anchor for the specified tag and name.  If it
 236 /// already exists, return it.  If not, create a new one and return it.
 237 DIAnchor DIFactory::GetOrCreateAnchor(unsigned TAG, const char *Name) {
 238   const Type *EltTy = StructType::get(Type::Int32Ty, Type::Int32Ty, NULL);
 239
 240   // Otherwise, create the global or return it if already in the module.
 241   Constant *C = M.getOrInsertGlobal(Name, EltTy);
 242   assert(isa<GlobalVariable>(C) && "Incorrectly typed anchor?");
 243   GlobalVariable *GV = cast<GlobalVariable>(C);
 244
 245   // If it has an initializer, it is already in the module.
 246   if (GV->hasInitializer())
 247     return SubProgramAnchor = DIAnchor(GV);
 248
 249   GV->setLinkage(GlobalValue::LinkOnceLinkage);
 250   GV->setSection("llvm.metadata");
 251   GV->setConstant(true);
 252   M.addTypeName("llvm.dbg.anchor.type", EltTy);
 253
 254   // Otherwise, set the initializer.
 255   Constant *Elts[] = {
 256     GetTagConstant(dwarf::DW_TAG_anchor),
 257     ConstantInt::get(Type::Int32Ty, TAG)
 258   };
 259
 260   GV->setInitializer(ConstantStruct::get(Elts, 2));
 261   return DIAnchor(GV);
 262 }
 263
 264
 265
 266 //===----------------------------------------------------------------------===//
 267 // DIFactory: Primary Constructors
 268 //===----------------------------------------------------------------------===//
 269
 270 /// GetOrCreateCompileUnitAnchor - Return the anchor for compile units,
 271 /// creating a new one if there isn't already one in the module.
 272 DIAnchor DIFactory::GetOrCreateCompileUnitAnchor() {
 273   // If we already created one, just return it.
 274   if (!CompileUnitAnchor.isNull())
 275     return CompileUnitAnchor;
 276   return CompileUnitAnchor = GetOrCreateAnchor(dwarf::DW_TAG_compile_unit,
 277                                                "llvm.dbg.compile_units");
 278 }
 279
 280 /// GetOrCreateSubprogramAnchor - Return the anchor for subprograms,
 281 /// creating a new one if there isn't already one in the module.
 282 DIAnchor DIFactory::GetOrCreateSubprogramAnchor() {
 283   // If we already created one, just return it.
 284   if (!SubProgramAnchor.isNull())
 285     return SubProgramAnchor;
 286   return SubProgramAnchor = GetOrCreateAnchor(dwarf::DW_TAG_subprogram,
 287                                               "llvm.dbg.subprograms");
 288 }
 289
 290 /// GetOrCreateGlobalVariableAnchor - Return the anchor for globals,
 291 /// creating a new one if there isn't already one in the module.
 292 DIAnchor DIFactory::GetOrCreateGlobalVariableAnchor() {
 293   // If we already created one, just return it.
 294   if (!GlobalVariableAnchor.isNull())
 295     return GlobalVariableAnchor;
 296   return GlobalVariableAnchor = GetOrCreateAnchor(dwarf::DW_TAG_variable,
 297                                                   "llvm.dbg.global_variables");
 298 }
 299
 300 /// GetOrCreateArray - Create an descriptor for an array of descriptors.
 301 /// This implicitly uniques the arrays created.
 302 DIArray DIFactory::GetOrCreateArray(DIDescriptor *Tys, unsigned NumTys) {
 303   SmallVector<Constant*, 16> Elts;
 304
 305   for (unsigned i = 0; i != NumTys; ++i)
 306     Elts.push_back(getCastToEmpty(Tys[i]));
 307
 308   Constant *Init = ConstantArray::get(ArrayType::get(EmptyStructPtr,
 309                                                      Elts.size()),
 310                                       &Elts[0], Elts.size());
 311   // If we already have this array, just return the uniqued version.
 312   DIDescriptor &Entry = SimpleConstantCache[Init];
 313   if (!Entry.isNull()) return DIArray(Entry.getGV());
 314
 315   GlobalVariable *GV = new GlobalVariable(Init->getType(), true,
 316                                           GlobalValue::InternalLinkage,
 317                                           Init, "llvm.dbg.array", &M);
 318   GV->setSection("llvm.metadata");
 319   Entry = DIDescriptor(GV);
 320   return DIArray(GV);
 321 }
 322
 323 /// GetOrCreateSubrange - Create a descriptor for a value range.  This
 324 /// implicitly uniques the values returned.
 325 DISubrange DIFactory::GetOrCreateSubrange(int64_t Lo, int64_t Hi) {
 326   Constant *Elts[] = {
 327     GetTagConstant(dwarf::DW_TAG_subrange_type),
 328     ConstantInt::get(Type::Int64Ty, Lo),
 329     ConstantInt::get(Type::Int64Ty, Hi)
 330   };
 331
 332   Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0]));
 333
 334   // If we already have this range, just return the uniqued version.
 335   DIDescriptor &Entry = SimpleConstantCache[Init];
 336   if (!Entry.isNull()) return DISubrange(Entry.getGV());
 337
 338   M.addTypeName("llvm.dbg.subrange.type", Init->getType());
 339
 340   GlobalVariable *GV = new GlobalVariable(Init->getType(), true,
 341                                           GlobalValue::InternalLinkage,
 342                                           Init, "llvm.dbg.subrange", &M);
 343   GV->setSection("llvm.metadata");
 344   Entry = DIDescriptor(GV);
 345   return DISubrange(GV);
 346 }
 347
 348
 349
 350 /// CreateCompileUnit - Create a new descriptor for the specified compile
 351 /// unit.  Note that this does not unique compile units within the module.
 352 DICompileUnit DIFactory::CreateCompileUnit(unsigned LangID,
 353                                            const std::string &Filename,
 354                                            const std::string &Directory,
 355                                            const std::string &Producer) {
 356   Constant *Elts[] = {
 357     GetTagConstant(dwarf::DW_TAG_compile_unit),
 358     getCastToEmpty(GetOrCreateCompileUnitAnchor()),
 359     ConstantInt::get(Type::Int32Ty, LangID),
 360     GetStringConstant(Filename),
 361     GetStringConstant(Directory),
 362     GetStringConstant(Producer)
 363   };
 364
 365   Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0]));
 366
 367   M.addTypeName("llvm.dbg.compile_unit.type", Init->getType());
 368   GlobalVariable *GV = new GlobalVariable(Init->getType(), true,
 369                                           GlobalValue::InternalLinkage,
 370                                           Init, "llvm.dbg.compile_unit", &M);
 371   GV->setSection("llvm.metadata");
 372   return DICompileUnit(GV);
 373 }
 374
 375 /// CreateEnumerator - Create a single enumerator value.
 376 DIEnumerator DIFactory::CreateEnumerator(const std::string &Name, uint64_t Val){
 377   Constant *Elts[] = {
 378     GetTagConstant(dwarf::DW_TAG_enumerator),
 379     GetStringConstant(Name),
 380     ConstantInt::get(Type::Int64Ty, Val)
 381   };
 382
 383   Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0]));
 384
 385   M.addTypeName("llvm.dbg.enumerator.type", Init->getType());
 386   GlobalVariable *GV = new GlobalVariable(Init->getType(), true,
 387                                           GlobalValue::InternalLinkage,
 388                                           Init, "llvm.dbg.enumerator", &M);
 389   GV->setSection("llvm.metadata");
 390   return DIEnumerator(GV);
 391 }
 392
 393
 394 /// CreateBasicType - Create a basic type like int, float, etc.
 395 DIBasicType DIFactory::CreateBasicType(DIDescriptor Context,
 396                                       const std::string &Name,
 397                                        DICompileUnit CompileUnit,
 398                                        unsigned LineNumber,
 399                                        uint64_t SizeInBits,
 400                                        uint64_t AlignInBits,
 401                                        uint64_t OffsetInBits, unsigned Flags,
 402                                        unsigned Encoding,
 403                                        const std::string *FileName,
 404                                        const std::string *Directory) {
 405   Constant *Elts[] = {
 406     GetTagConstant(dwarf::DW_TAG_base_type),
 407     getCastToEmpty(Context),
 408     GetStringConstant(Name),
 409     getCastToEmpty(CompileUnit),
 410     ConstantInt::get(Type::Int32Ty, LineNumber),
 411     ConstantInt::get(Type::Int64Ty, SizeInBits),
 412     ConstantInt::get(Type::Int64Ty, AlignInBits),
 413     ConstantInt::get(Type::Int64Ty, OffsetInBits),
 414     ConstantInt::get(Type::Int32Ty, Flags),
 415     ConstantInt::get(Type::Int32Ty, Encoding),
 416     GetStringConstant(FileName ? FileName->c_str() : ""),
 417     GetStringConstant(Directory ? Directory->c_str() : "")
 418   };
 419
 420   Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0]));
 421
 422   M.addTypeName("llvm.dbg.basictype.type", Init->getType());
 423   GlobalVariable *GV = new GlobalVariable(Init->getType(), true,
 424                                           GlobalValue::InternalLinkage,
 425                                           Init, "llvm.dbg.basictype", &M);
 426   GV->setSection("llvm.metadata");
 427   return DIBasicType(GV);
 428 }
 429
 430 /// CreateDerivedType - Create a derived type like const qualified type,
 431 /// pointer, typedef, etc.
 432 DIDerivedType DIFactory::CreateDerivedType(unsigned Tag,
 433                                            DIDescriptor Context,
 434                                            const std::string &Name,
 435                                            DICompileUnit CompileUnit,
 436                                            unsigned LineNumber,
 437                                            uint64_t SizeInBits,
 438                                            uint64_t AlignInBits,
 439                                            uint64_t OffsetInBits,
 440                                            unsigned Flags,
 441                                            DIType DerivedFrom,
 442                                            const std::string *FileName,
 443                                            const std::string *Directory) {
 444   Constant *Elts[] = {
 445     GetTagConstant(Tag),
 446     getCastToEmpty(Context),
 447     GetStringConstant(Name),
 448     getCastToEmpty(CompileUnit),
 449     ConstantInt::get(Type::Int32Ty, LineNumber),
 450     ConstantInt::get(Type::Int64Ty, SizeInBits),
 451     ConstantInt::get(Type::Int64Ty, AlignInBits),
 452     ConstantInt::get(Type::Int64Ty, OffsetInBits),
 453     ConstantInt::get(Type::Int32Ty, Flags),
 454     getCastToEmpty(DerivedFrom),
 455     GetStringConstant(FileName ? FileName->c_str() : ""),
 456     GetStringConstant(Directory ? Directory->c_str() : "")
 457   };
 458
 459   Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0]));
 460
 461   M.addTypeName("llvm.dbg.derivedtype.type", Init->getType());
 462   GlobalVariable *GV = new GlobalVariable(Init->getType(), true,
 463                                           GlobalValue::InternalLinkage,
 464                                           Init, "llvm.dbg.derivedtype", &M);
 465   GV->setSection("llvm.metadata");
 466   return DIDerivedType(GV);
 467 }
 468
 469 /// CreateCompositeType - Create a composite type like array, struct, etc.
 470 DICompositeType DIFactory::CreateCompositeType(unsigned Tag,
 471                                                DIDescriptor Context,
 472                                                const std::string &Name,
 473                                                DICompileUnit CompileUnit,
 474                                                unsigned LineNumber,
 475                                                uint64_t SizeInBits,
 476                                                uint64_t AlignInBits,
 477                                                uint64_t OffsetInBits,
 478                                                unsigned Flags,
 479                                                DIType DerivedFrom,
 480                                                DIArray Elements,
 481                                                const std::string *FileName,
 482                                                const std::string *Directory) {
 483
 484   Constant *Elts[] = {
 485     GetTagConstant(Tag),
 486     getCastToEmpty(Context),
 487     GetStringConstant(Name),
 488     getCastToEmpty(CompileUnit),
 489     ConstantInt::get(Type::Int32Ty, LineNumber),
 490     ConstantInt::get(Type::Int64Ty, SizeInBits),
 491     ConstantInt::get(Type::Int64Ty, AlignInBits),
 492     ConstantInt::get(Type::Int64Ty, OffsetInBits),
 493     ConstantInt::get(Type::Int32Ty, Flags),
 494     getCastToEmpty(DerivedFrom),
 495     getCastToEmpty(Elements),
 496     GetStringConstant(FileName ? FileName->c_str() : ""),
 497     GetStringConstant(Directory ? Directory->c_str() : "")
 498   };
 499
 500   Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0]));
 501
 502   M.addTypeName("llvm.dbg.composite.type", Init->getType());
 503   GlobalVariable *GV = new GlobalVariable(Init->getType(), true,
 504                                           GlobalValue::InternalLinkage,
 505                                           Init, "llvm.dbg.composite", &M);
 506   GV->setSection("llvm.metadata");
 507   return DICompositeType(GV);
 508 }
 509
 510
 511 /// CreateSubprogram - Create a new descriptor for the specified subprogram.
 512 /// See comments in DISubprogram for descriptions of these fields.  This
 513 /// method does not unique the generated descriptors.
 514 DISubprogram DIFactory::CreateSubprogram(DIDescriptor Context,
 515                                          const std::string &Name,
 516                                          const std::string &DisplayName,
 517                                          const std::string &LinkageName,
 518                                          DICompileUnit CompileUnit,
 519                                          unsigned LineNo, DIType Type,
 520                                          bool isLocalToUnit,
 521                                          bool isDefinition,
 522                                          const std::string *FileName,
 523                                          const std::string *Directory) {
 524
 525   Constant *Elts[] = {
 526     GetTagConstant(dwarf::DW_TAG_subprogram),
 527     getCastToEmpty(GetOrCreateSubprogramAnchor()),
 528     getCastToEmpty(Context),
 529     GetStringConstant(Name),
 530     GetStringConstant(DisplayName),
 531     GetStringConstant(LinkageName),
 532     getCastToEmpty(CompileUnit),
 533     ConstantInt::get(Type::Int32Ty, LineNo),
 534     getCastToEmpty(Type),
 535     ConstantInt::get(Type::Int1Ty, isLocalToUnit),
 536     ConstantInt::get(Type::Int1Ty, isDefinition),
 537     GetStringConstant(FileName ? FileName->c_str() : ""),
 538     GetStringConstant(Directory ? Directory->c_str() : "")
 539   };
 540
 541   Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0]));
 542
 543   M.addTypeName("llvm.dbg.subprogram.type", Init->getType());
 544   GlobalVariable *GV = new GlobalVariable(Init->getType(), true,
 545                                           GlobalValue::InternalLinkage,
 546                                           Init, "llvm.dbg.subprogram", &M);
 547   GV->setSection("llvm.metadata");
 548   return DISubprogram(GV);
 549 }
 550
 551 /// CreateGlobalVariable - Create a new descriptor for the specified global.
 552 DIGlobalVariable
 553 DIFactory::CreateGlobalVariable(DIDescriptor Context, const std::string &Name,
 554                                 const std::string &DisplayName,
 555                                 const std::string &LinkageName,
 556                                 DICompileUnit CompileUnit,
 557                                 unsigned LineNo, DIType Type,bool isLocalToUnit,
 558                                 bool isDefinition, llvm::GlobalVariable *Val,
 559                                 const std::string *FileName,
 560                                 const std::string *Directory) {
 561   Constant *Elts[] = {
 562     GetTagConstant(dwarf::DW_TAG_variable),
 563     getCastToEmpty(GetOrCreateGlobalVariableAnchor()),
 564     getCastToEmpty(Context),
 565     GetStringConstant(Name),
 566     GetStringConstant(DisplayName),
 567     GetStringConstant(LinkageName),
 568     getCastToEmpty(CompileUnit),
 569     ConstantInt::get(Type::Int32Ty, LineNo),
 570     getCastToEmpty(Type),
 571     ConstantInt::get(Type::Int1Ty, isLocalToUnit),
 572     ConstantInt::get(Type::Int1Ty, isDefinition),
 573     ConstantExpr::getBitCast(Val, EmptyStructPtr),
 574     GetStringConstant(FileName ? FileName->c_str() : ""),
 575     GetStringConstant(Directory ? Directory->c_str() : "")
 576   };
 577
 578   Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0]));
 579
 580   M.addTypeName("llvm.dbg.global_variable.type", Init->getType());
 581   GlobalVariable *GV = new GlobalVariable(Init->getType(), true,
 582                                           GlobalValue::InternalLinkage,
 583                                           Init, "llvm.dbg.global_variable", &M);
 584   GV->setSection("llvm.metadata");
 585   return DIGlobalVariable(GV);
 586 }
 587
 588
 589 /// CreateVariable - Create a new descriptor for the specified variable.
 590 DIVariable DIFactory::CreateVariable(unsigned Tag, DIDescriptor Context,
 591                                      const std::string &Name,
 592                                      DICompileUnit CompileUnit, unsigned LineNo,
 593                                      DIType Type,
 594                                      const std::string *FileName,
 595                                      const std::string *Directory) {
 596
 597
 598   Constant *Elts[] = {
 599     GetTagConstant(Tag),
 600     getCastToEmpty(Context),
 601     GetStringConstant(Name),
 602     getCastToEmpty(CompileUnit),
 603     ConstantInt::get(Type::Int32Ty, LineNo),
 604     getCastToEmpty(Type),
 605     GetStringConstant(FileName ? FileName->c_str() : ""),
 606     GetStringConstant(Directory ? Directory->c_str() : "")
 607   };
 608
 609   Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0]));
 610
 611   M.addTypeName("llvm.dbg.variable.type", Init->getType());
 612   GlobalVariable *GV = new GlobalVariable(Init->getType(), true,
 613                                           GlobalValue::InternalLinkage,
 614                                           Init, "llvm.dbg.variable", &M);
 615   GV->setSection("llvm.metadata");
 616   return DIVariable(GV);
 617 }
 618
 619
 620 /// CreateBlock - This creates a descriptor for a lexical block with the
 621 /// specified parent context.
 622 DIBlock DIFactory::CreateBlock(DIDescriptor Context) {
 623   Constant *Elts[] = {
 624     GetTagConstant(dwarf::DW_TAG_lexical_block),
 625     getCastToEmpty(Context)
 626   };
 627
 628   Constant *Init = ConstantStruct::get(Elts, sizeof(Elts)/sizeof(Elts[0]));
 629
 630   M.addTypeName("llvm.dbg.block.type", Init->getType());
 631   GlobalVariable *GV = new GlobalVariable(Init->getType(), true,
 632                                           GlobalValue::InternalLinkage,
 633                                           Init, "llvm.dbg.block", &M);
 634   GV->setSection("llvm.metadata");
 635   return DIBlock(GV);
 636 }
 637
 638
 639 //===----------------------------------------------------------------------===//
 640 // DIFactory: Routines for inserting code into a function
 641 //===----------------------------------------------------------------------===//
 642
 643 /// InsertStopPoint - Create a new llvm.dbg.stoppoint intrinsic invocation,
 644 /// inserting it at the end of the specified basic block.
 645 void DIFactory::InsertStopPoint(DICompileUnit CU, unsigned LineNo,
 646                                 unsigned ColNo, BasicBlock *BB) {
 647
 648   // Lazily construct llvm.dbg.stoppoint function.
 649   if (!StopPointFn)
 650     StopPointFn = llvm::Intrinsic::getDeclaration(&M,
 651                                               llvm::Intrinsic::dbg_stoppoint);
 652
 653   // Invoke llvm.dbg.stoppoint
 654   Value *Args[] = {
 655     llvm::ConstantInt::get(llvm::Type::Int32Ty, LineNo),
 656     llvm::ConstantInt::get(llvm::Type::Int32Ty, ColNo),
 657     getCastToEmpty(CU)
 658   };
 659   CallInst::Create(StopPointFn, Args, Args+3, "", BB);
 660 }
 661
 662 /// InsertSubprogramStart - Create a new llvm.dbg.func.start intrinsic to
 663 /// mark the start of the specified subprogram.
 664 void DIFactory::InsertSubprogramStart(DISubprogram SP, BasicBlock *BB) {
 665   // Lazily construct llvm.dbg.func.start.
 666   if (!FuncStartFn)
 667     FuncStartFn = llvm::Intrinsic::getDeclaration(&M,
 668                                               llvm::Intrinsic::dbg_func_start);
 669
 670   // Call llvm.dbg.func.start which also implicitly sets a stoppoint.
 671   CallInst::Create(FuncStartFn, getCastToEmpty(SP), "", BB);
 672 }
 673
 674 /// InsertRegionStart - Insert a new llvm.dbg.region.start intrinsic call to
 675 /// mark the start of a region for the specified scoping descriptor.
 676 void DIFactory::InsertRegionStart(DIDescriptor D, BasicBlock *BB) {
 677   // Lazily construct llvm.dbg.region.start function.
 678   if (!RegionStartFn)
 679     RegionStartFn = llvm::Intrinsic::getDeclaration(&M,
 680                                             llvm::Intrinsic::dbg_region_start);
 681   // Call llvm.dbg.func.start.
 682   CallInst::Create(RegionStartFn, getCastToEmpty(D), "", BB);
 683 }
 684
 685
 686 /// InsertRegionEnd - Insert a new llvm.dbg.region.end intrinsic call to
 687 /// mark the end of a region for the specified scoping descriptor.
 688 void DIFactory::InsertRegionEnd(DIDescriptor D, BasicBlock *BB) {
 689   // Lazily construct llvm.dbg.region.end function.
 690   if (!RegionEndFn)
 691     RegionEndFn = llvm::Intrinsic::getDeclaration(&M,
 692                                                llvm::Intrinsic::dbg_region_end);
 693
 694   CallInst::Create(RegionEndFn, getCastToEmpty(D), "", BB);
 695 }
 696
 697 /// InsertDeclare - Insert a new llvm.dbg.declare intrinsic call.
 698 void DIFactory::InsertDeclare(llvm::Value *Storage, DIVariable D,
 699                               BasicBlock *BB) {
 700   // Cast the storage to a {}* for the call to llvm.dbg.declare.
 701   Storage = new llvm::BitCastInst(Storage, EmptyStructPtr, "", BB);
 702
 703   if (!DeclareFn)
 704     DeclareFn = llvm::Intrinsic::getDeclaration(&M,
 705                                                 llvm::Intrinsic::dbg_declare);
 706   Value *Args[] = { Storage, getCastToEmpty(D) };
 707   CallInst::Create(DeclareFn, Args, Args+2, "", BB);
 708 }
 709
 710 namespace llvm {
 711   /// Finds the stoppoint coressponding to this instruction, that is the
 712   /// stoppoint that dominates this instruction
 713   const DbgStopPointInst *findStopPoint(const Instruction *Inst)
 714   {
 715     if (const DbgStopPointInst *DSI = dyn_cast<DbgStopPointInst>(Inst))
 716       return DSI;
 717
 718     const BasicBlock *BB = Inst->getParent();
 719     BasicBlock::const_iterator I = Inst, B;
 720     do {
 721       B = BB->begin();
 722       // A BB consisting only of a terminator can't have a stoppoint.
 723       if (I != B) {
 724         do {
 725           --I;
 726           if (const DbgStopPointInst *DSI = dyn_cast<DbgStopPointInst>(I))
 727             return DSI;
 728         } while (I != B);
 729       }
 730       // This BB didn't have a stoppoint: if there is only one
 731       // predecessor, look for a stoppoint there.
 732       // We could use getIDom(), but that would require dominator info.
 733       BB = I->getParent()->getUniquePredecessor();
 734       if (BB)
 735         I = BB->getTerminator();
 736     } while (BB != 0);
 737     return 0;
 738   }
 739
 740   /// Finds the stoppoint corresponding to first real (non-debug intrinsic)
 741   /// instruction in this Basic Block, and returns the stoppoint for it.
 742   const DbgStopPointInst *findBBStopPoint(const BasicBlock *BB)
 743   {
 744     for(BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I != E; ++I) {
 745       if (const DbgStopPointInst *DSI = dyn_cast<DbgStopPointInst>(I))
 746         return DSI;
 747     }
 748     // Fallback to looking for stoppoint of unique predecessor.
 749     // Useful if this BB contains no stoppoints, but unique predecessor does.
 750     BB = BB->getUniquePredecessor();
 751     if (BB)
 752       return findStopPoint(BB->getTerminator());
 753     return 0;
 754   }
 755
 756   /// Finds the dbg.declare intrinsic corresponding to this value if any.
 757   /// It looks through pointer casts too.
 758   const DbgDeclareInst *findDbgDeclare(const Value *V, bool stripCasts)
 759   {
 760     if (stripCasts) {
 761       V = V->stripPointerCasts();
 762       // Look for the bitcast.
 763       for (Value::use_const_iterator I = V->use_begin(), E =V->use_end();
 764             I != E; ++I) {
 765         if (isa<BitCastInst>(I))
 766           return findDbgDeclare(*I, false);
 767       }
 768       return 0;
 769     }
 770
 771     // Find dbg.declare among uses of the instruction.
 772     for (Value::use_const_iterator I = V->use_begin(), E =V->use_end();
 773           I != E; ++I) {
 774       if (const DbgDeclareInst *DDI = dyn_cast<DbgDeclareInst>(I))
 775         return DDI;
 776     }
 777     return 0;
 778   }
 779 }
 780