MemRegion.cpp revision e17fdb2d5dbf0ffefd417587003eebbe5baf5984
1//== MemRegion.cpp - Abstract memory regions for static analysis --*- 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 defines MemRegion and its subclasses. MemRegion defines a 11// partially-typed abstraction of memory useful for path-sensitive dataflow 12// analyses. 13// 14//===----------------------------------------------------------------------===// 15 16#include "clang/StaticAnalyzer/Core/PathSensitive/MemRegion.h" 17#include "clang/StaticAnalyzer/Core/PathSensitive/SValBuilder.h" 18#include "clang/Analysis/AnalysisContext.h" 19#include "clang/Analysis/Support/BumpVector.h" 20#include "clang/AST/CharUnits.h" 21#include "clang/AST/DeclObjC.h" 22#include "clang/AST/RecordLayout.h" 23#include "clang/Basic/SourceManager.h" 24#include "llvm/Support/raw_ostream.h" 25 26using namespace clang; 27using namespace ento; 28 29//===----------------------------------------------------------------------===// 30// MemRegion Construction. 31//===----------------------------------------------------------------------===// 32 33template<typename RegionTy> struct MemRegionManagerTrait; 34 35template <typename RegionTy, typename A1> 36RegionTy* MemRegionManager::getRegion(const A1 a1) { 37 38 const typename MemRegionManagerTrait<RegionTy>::SuperRegionTy *superRegion = 39 MemRegionManagerTrait<RegionTy>::getSuperRegion(*this, a1); 40 41 llvm::FoldingSetNodeID ID; 42 RegionTy::ProfileRegion(ID, a1, superRegion); 43 void *InsertPos; 44 RegionTy* R = cast_or_null<RegionTy>(Regions.FindNodeOrInsertPos(ID, 45 InsertPos)); 46 47 if (!R) { 48 R = (RegionTy*) A.Allocate<RegionTy>(); 49 new (R) RegionTy(a1, superRegion); 50 Regions.InsertNode(R, InsertPos); 51 } 52 53 return R; 54} 55 56template <typename RegionTy, typename A1> 57RegionTy* MemRegionManager::getSubRegion(const A1 a1, 58 const MemRegion *superRegion) { 59 llvm::FoldingSetNodeID ID; 60 RegionTy::ProfileRegion(ID, a1, superRegion); 61 void *InsertPos; 62 RegionTy* R = cast_or_null<RegionTy>(Regions.FindNodeOrInsertPos(ID, 63 InsertPos)); 64 65 if (!R) { 66 R = (RegionTy*) A.Allocate<RegionTy>(); 67 new (R) RegionTy(a1, superRegion); 68 Regions.InsertNode(R, InsertPos); 69 } 70 71 return R; 72} 73 74template <typename RegionTy, typename A1, typename A2> 75RegionTy* MemRegionManager::getRegion(const A1 a1, const A2 a2) { 76 77 const typename MemRegionManagerTrait<RegionTy>::SuperRegionTy *superRegion = 78 MemRegionManagerTrait<RegionTy>::getSuperRegion(*this, a1, a2); 79 80 llvm::FoldingSetNodeID ID; 81 RegionTy::ProfileRegion(ID, a1, a2, superRegion); 82 void *InsertPos; 83 RegionTy* R = cast_or_null<RegionTy>(Regions.FindNodeOrInsertPos(ID, 84 InsertPos)); 85 86 if (!R) { 87 R = (RegionTy*) A.Allocate<RegionTy>(); 88 new (R) RegionTy(a1, a2, superRegion); 89 Regions.InsertNode(R, InsertPos); 90 } 91 92 return R; 93} 94 95template <typename RegionTy, typename A1, typename A2> 96RegionTy* MemRegionManager::getSubRegion(const A1 a1, const A2 a2, 97 const MemRegion *superRegion) { 98 99 llvm::FoldingSetNodeID ID; 100 RegionTy::ProfileRegion(ID, a1, a2, superRegion); 101 void *InsertPos; 102 RegionTy* R = cast_or_null<RegionTy>(Regions.FindNodeOrInsertPos(ID, 103 InsertPos)); 104 105 if (!R) { 106 R = (RegionTy*) A.Allocate<RegionTy>(); 107 new (R) RegionTy(a1, a2, superRegion); 108 Regions.InsertNode(R, InsertPos); 109 } 110 111 return R; 112} 113 114template <typename RegionTy, typename A1, typename A2, typename A3> 115RegionTy* MemRegionManager::getSubRegion(const A1 a1, const A2 a2, const A3 a3, 116 const MemRegion *superRegion) { 117 118 llvm::FoldingSetNodeID ID; 119 RegionTy::ProfileRegion(ID, a1, a2, a3, superRegion); 120 void *InsertPos; 121 RegionTy* R = cast_or_null<RegionTy>(Regions.FindNodeOrInsertPos(ID, 122 InsertPos)); 123 124 if (!R) { 125 R = (RegionTy*) A.Allocate<RegionTy>(); 126 new (R) RegionTy(a1, a2, a3, superRegion); 127 Regions.InsertNode(R, InsertPos); 128 } 129 130 return R; 131} 132 133//===----------------------------------------------------------------------===// 134// Object destruction. 135//===----------------------------------------------------------------------===// 136 137MemRegion::~MemRegion() {} 138 139MemRegionManager::~MemRegionManager() { 140 // All regions and their data are BumpPtrAllocated. No need to call 141 // their destructors. 142} 143 144//===----------------------------------------------------------------------===// 145// Basic methods. 146//===----------------------------------------------------------------------===// 147 148bool SubRegion::isSubRegionOf(const MemRegion* R) const { 149 const MemRegion* r = getSuperRegion(); 150 while (r != 0) { 151 if (r == R) 152 return true; 153 if (const SubRegion* sr = dyn_cast<SubRegion>(r)) 154 r = sr->getSuperRegion(); 155 else 156 break; 157 } 158 return false; 159} 160 161MemRegionManager* SubRegion::getMemRegionManager() const { 162 const SubRegion* r = this; 163 do { 164 const MemRegion *superRegion = r->getSuperRegion(); 165 if (const SubRegion *sr = dyn_cast<SubRegion>(superRegion)) { 166 r = sr; 167 continue; 168 } 169 return superRegion->getMemRegionManager(); 170 } while (1); 171} 172 173const StackFrameContext *VarRegion::getStackFrame() const { 174 const StackSpaceRegion *SSR = dyn_cast<StackSpaceRegion>(getMemorySpace()); 175 return SSR ? SSR->getStackFrame() : NULL; 176} 177 178//===----------------------------------------------------------------------===// 179// Region extents. 180//===----------------------------------------------------------------------===// 181 182DefinedOrUnknownSVal DeclRegion::getExtent(SValBuilder &svalBuilder) const { 183 ASTContext &Ctx = svalBuilder.getContext(); 184 QualType T = getDesugaredValueType(Ctx); 185 186 if (isa<VariableArrayType>(T)) 187 return nonloc::SymbolVal(svalBuilder.getSymbolManager().getExtentSymbol(this)); 188 if (isa<IncompleteArrayType>(T)) 189 return UnknownVal(); 190 191 CharUnits size = Ctx.getTypeSizeInChars(T); 192 QualType sizeTy = svalBuilder.getArrayIndexType(); 193 return svalBuilder.makeIntVal(size.getQuantity(), sizeTy); 194} 195 196DefinedOrUnknownSVal FieldRegion::getExtent(SValBuilder &svalBuilder) const { 197 DefinedOrUnknownSVal Extent = DeclRegion::getExtent(svalBuilder); 198 199 // A zero-length array at the end of a struct often stands for dynamically- 200 // allocated extra memory. 201 if (Extent.isZeroConstant()) { 202 QualType T = getDesugaredValueType(svalBuilder.getContext()); 203 204 if (isa<ConstantArrayType>(T)) 205 return UnknownVal(); 206 } 207 208 return Extent; 209} 210 211DefinedOrUnknownSVal AllocaRegion::getExtent(SValBuilder &svalBuilder) const { 212 return nonloc::SymbolVal(svalBuilder.getSymbolManager().getExtentSymbol(this)); 213} 214 215DefinedOrUnknownSVal SymbolicRegion::getExtent(SValBuilder &svalBuilder) const { 216 return nonloc::SymbolVal(svalBuilder.getSymbolManager().getExtentSymbol(this)); 217} 218 219DefinedOrUnknownSVal StringRegion::getExtent(SValBuilder &svalBuilder) const { 220 return svalBuilder.makeIntVal(getStringLiteral()->getByteLength()+1, 221 svalBuilder.getArrayIndexType()); 222} 223 224ObjCIvarRegion::ObjCIvarRegion(const ObjCIvarDecl *ivd, const MemRegion* sReg) 225 : DeclRegion(ivd, sReg, ObjCIvarRegionKind) {} 226 227const ObjCIvarDecl *ObjCIvarRegion::getDecl() const { 228 return cast<ObjCIvarDecl>(D); 229} 230 231QualType ObjCIvarRegion::getValueType() const { 232 return getDecl()->getType(); 233} 234 235QualType CXXBaseObjectRegion::getValueType() const { 236 return QualType(decl->getTypeForDecl(), 0); 237} 238 239//===----------------------------------------------------------------------===// 240// FoldingSet profiling. 241//===----------------------------------------------------------------------===// 242 243void MemSpaceRegion::Profile(llvm::FoldingSetNodeID& ID) const { 244 ID.AddInteger((unsigned)getKind()); 245} 246 247void StackSpaceRegion::Profile(llvm::FoldingSetNodeID &ID) const { 248 ID.AddInteger((unsigned)getKind()); 249 ID.AddPointer(getStackFrame()); 250} 251 252void StaticGlobalSpaceRegion::Profile(llvm::FoldingSetNodeID &ID) const { 253 ID.AddInteger((unsigned)getKind()); 254 ID.AddPointer(getCodeRegion()); 255} 256 257void StringRegion::ProfileRegion(llvm::FoldingSetNodeID& ID, 258 const StringLiteral* Str, 259 const MemRegion* superRegion) { 260 ID.AddInteger((unsigned) StringRegionKind); 261 ID.AddPointer(Str); 262 ID.AddPointer(superRegion); 263} 264 265void ObjCStringRegion::ProfileRegion(llvm::FoldingSetNodeID& ID, 266 const ObjCStringLiteral* Str, 267 const MemRegion* superRegion) { 268 ID.AddInteger((unsigned) ObjCStringRegionKind); 269 ID.AddPointer(Str); 270 ID.AddPointer(superRegion); 271} 272 273void AllocaRegion::ProfileRegion(llvm::FoldingSetNodeID& ID, 274 const Expr *Ex, unsigned cnt, 275 const MemRegion *) { 276 ID.AddInteger((unsigned) AllocaRegionKind); 277 ID.AddPointer(Ex); 278 ID.AddInteger(cnt); 279} 280 281void AllocaRegion::Profile(llvm::FoldingSetNodeID& ID) const { 282 ProfileRegion(ID, Ex, Cnt, superRegion); 283} 284 285void CompoundLiteralRegion::Profile(llvm::FoldingSetNodeID& ID) const { 286 CompoundLiteralRegion::ProfileRegion(ID, CL, superRegion); 287} 288 289void CompoundLiteralRegion::ProfileRegion(llvm::FoldingSetNodeID& ID, 290 const CompoundLiteralExpr *CL, 291 const MemRegion* superRegion) { 292 ID.AddInteger((unsigned) CompoundLiteralRegionKind); 293 ID.AddPointer(CL); 294 ID.AddPointer(superRegion); 295} 296 297void CXXThisRegion::ProfileRegion(llvm::FoldingSetNodeID &ID, 298 const PointerType *PT, 299 const MemRegion *sRegion) { 300 ID.AddInteger((unsigned) CXXThisRegionKind); 301 ID.AddPointer(PT); 302 ID.AddPointer(sRegion); 303} 304 305void CXXThisRegion::Profile(llvm::FoldingSetNodeID &ID) const { 306 CXXThisRegion::ProfileRegion(ID, ThisPointerTy, superRegion); 307} 308 309void ObjCIvarRegion::ProfileRegion(llvm::FoldingSetNodeID& ID, 310 const ObjCIvarDecl *ivd, 311 const MemRegion* superRegion) { 312 DeclRegion::ProfileRegion(ID, ivd, superRegion, ObjCIvarRegionKind); 313} 314 315void DeclRegion::ProfileRegion(llvm::FoldingSetNodeID& ID, const Decl *D, 316 const MemRegion* superRegion, Kind k) { 317 ID.AddInteger((unsigned) k); 318 ID.AddPointer(D); 319 ID.AddPointer(superRegion); 320} 321 322void DeclRegion::Profile(llvm::FoldingSetNodeID& ID) const { 323 DeclRegion::ProfileRegion(ID, D, superRegion, getKind()); 324} 325 326void VarRegion::Profile(llvm::FoldingSetNodeID &ID) const { 327 VarRegion::ProfileRegion(ID, getDecl(), superRegion); 328} 329 330void SymbolicRegion::ProfileRegion(llvm::FoldingSetNodeID& ID, SymbolRef sym, 331 const MemRegion *sreg) { 332 ID.AddInteger((unsigned) MemRegion::SymbolicRegionKind); 333 ID.Add(sym); 334 ID.AddPointer(sreg); 335} 336 337void SymbolicRegion::Profile(llvm::FoldingSetNodeID& ID) const { 338 SymbolicRegion::ProfileRegion(ID, sym, getSuperRegion()); 339} 340 341void ElementRegion::ProfileRegion(llvm::FoldingSetNodeID& ID, 342 QualType ElementType, SVal Idx, 343 const MemRegion* superRegion) { 344 ID.AddInteger(MemRegion::ElementRegionKind); 345 ID.Add(ElementType); 346 ID.AddPointer(superRegion); 347 Idx.Profile(ID); 348} 349 350void ElementRegion::Profile(llvm::FoldingSetNodeID& ID) const { 351 ElementRegion::ProfileRegion(ID, ElementType, Index, superRegion); 352} 353 354void FunctionTextRegion::ProfileRegion(llvm::FoldingSetNodeID& ID, 355 const FunctionDecl *FD, 356 const MemRegion*) { 357 ID.AddInteger(MemRegion::FunctionTextRegionKind); 358 ID.AddPointer(FD); 359} 360 361void FunctionTextRegion::Profile(llvm::FoldingSetNodeID& ID) const { 362 FunctionTextRegion::ProfileRegion(ID, FD, superRegion); 363} 364 365void BlockTextRegion::ProfileRegion(llvm::FoldingSetNodeID& ID, 366 const BlockDecl *BD, CanQualType, 367 const AnalysisDeclContext *AC, 368 const MemRegion*) { 369 ID.AddInteger(MemRegion::BlockTextRegionKind); 370 ID.AddPointer(BD); 371} 372 373void BlockTextRegion::Profile(llvm::FoldingSetNodeID& ID) const { 374 BlockTextRegion::ProfileRegion(ID, BD, locTy, AC, superRegion); 375} 376 377void BlockDataRegion::ProfileRegion(llvm::FoldingSetNodeID& ID, 378 const BlockTextRegion *BC, 379 const LocationContext *LC, 380 const MemRegion *sReg) { 381 ID.AddInteger(MemRegion::BlockDataRegionKind); 382 ID.AddPointer(BC); 383 ID.AddPointer(LC); 384 ID.AddPointer(sReg); 385} 386 387void BlockDataRegion::Profile(llvm::FoldingSetNodeID& ID) const { 388 BlockDataRegion::ProfileRegion(ID, BC, LC, getSuperRegion()); 389} 390 391void CXXTempObjectRegion::ProfileRegion(llvm::FoldingSetNodeID &ID, 392 Expr const *Ex, 393 const MemRegion *sReg) { 394 ID.AddPointer(Ex); 395 ID.AddPointer(sReg); 396} 397 398void CXXTempObjectRegion::Profile(llvm::FoldingSetNodeID &ID) const { 399 ProfileRegion(ID, Ex, getSuperRegion()); 400} 401 402void CXXBaseObjectRegion::ProfileRegion(llvm::FoldingSetNodeID &ID, 403 const CXXRecordDecl *decl, 404 const MemRegion *sReg) { 405 ID.AddPointer(decl); 406 ID.AddPointer(sReg); 407} 408 409void CXXBaseObjectRegion::Profile(llvm::FoldingSetNodeID &ID) const { 410 ProfileRegion(ID, decl, superRegion); 411} 412 413//===----------------------------------------------------------------------===// 414// Region anchors. 415//===----------------------------------------------------------------------===// 416 417void GlobalsSpaceRegion::anchor() { } 418void HeapSpaceRegion::anchor() { } 419void UnknownSpaceRegion::anchor() { } 420void StackLocalsSpaceRegion::anchor() { } 421void StackArgumentsSpaceRegion::anchor() { } 422void TypedRegion::anchor() { } 423void TypedValueRegion::anchor() { } 424void CodeTextRegion::anchor() { } 425void SubRegion::anchor() { } 426 427//===----------------------------------------------------------------------===// 428// Region pretty-printing. 429//===----------------------------------------------------------------------===// 430 431void MemRegion::dump() const { 432 dumpToStream(llvm::errs()); 433} 434 435std::string MemRegion::getString() const { 436 std::string s; 437 llvm::raw_string_ostream os(s); 438 dumpToStream(os); 439 return os.str(); 440} 441 442void MemRegion::dumpToStream(raw_ostream &os) const { 443 os << "<Unknown Region>"; 444} 445 446void AllocaRegion::dumpToStream(raw_ostream &os) const { 447 os << "alloca{" << (void*) Ex << ',' << Cnt << '}'; 448} 449 450void FunctionTextRegion::dumpToStream(raw_ostream &os) const { 451 os << "code{" << getDecl()->getDeclName().getAsString() << '}'; 452} 453 454void BlockTextRegion::dumpToStream(raw_ostream &os) const { 455 os << "block_code{" << (void*) this << '}'; 456} 457 458void BlockDataRegion::dumpToStream(raw_ostream &os) const { 459 os << "block_data{" << BC << '}'; 460} 461 462void CompoundLiteralRegion::dumpToStream(raw_ostream &os) const { 463 // FIXME: More elaborate pretty-printing. 464 os << "{ " << (void*) CL << " }"; 465} 466 467void CXXTempObjectRegion::dumpToStream(raw_ostream &os) const { 468 os << "temp_object{" << getValueType().getAsString() << ',' 469 << (void*) Ex << '}'; 470} 471 472void CXXBaseObjectRegion::dumpToStream(raw_ostream &os) const { 473 os << "base " << decl->getName(); 474} 475 476void CXXThisRegion::dumpToStream(raw_ostream &os) const { 477 os << "this"; 478} 479 480void ElementRegion::dumpToStream(raw_ostream &os) const { 481 os << "element{" << superRegion << ',' 482 << Index << ',' << getElementType().getAsString() << '}'; 483} 484 485void FieldRegion::dumpToStream(raw_ostream &os) const { 486 os << superRegion << "->" << *getDecl(); 487} 488 489void ObjCIvarRegion::dumpToStream(raw_ostream &os) const { 490 os << "ivar{" << superRegion << ',' << *getDecl() << '}'; 491} 492 493void StringRegion::dumpToStream(raw_ostream &os) const { 494 Str->printPretty(os, 0, PrintingPolicy(getContext().getLangOpts())); 495} 496 497void ObjCStringRegion::dumpToStream(raw_ostream &os) const { 498 Str->printPretty(os, 0, PrintingPolicy(getContext().getLangOpts())); 499} 500 501void SymbolicRegion::dumpToStream(raw_ostream &os) const { 502 os << "SymRegion{" << sym << '}'; 503} 504 505void VarRegion::dumpToStream(raw_ostream &os) const { 506 os << *cast<VarDecl>(D); 507} 508 509void RegionRawOffset::dump() const { 510 dumpToStream(llvm::errs()); 511} 512 513void RegionRawOffset::dumpToStream(raw_ostream &os) const { 514 os << "raw_offset{" << getRegion() << ',' << getOffset().getQuantity() << '}'; 515} 516 517void StaticGlobalSpaceRegion::dumpToStream(raw_ostream &os) const { 518 os << "StaticGlobalsMemSpace{" << CR << '}'; 519} 520 521void GlobalInternalSpaceRegion::dumpToStream(raw_ostream &os) const { 522 os << "GlobalInternalSpaceRegion"; 523} 524 525void GlobalSystemSpaceRegion::dumpToStream(raw_ostream &os) const { 526 os << "GlobalSystemSpaceRegion"; 527} 528 529void GlobalImmutableSpaceRegion::dumpToStream(raw_ostream &os) const { 530 os << "GlobalImmutableSpaceRegion"; 531} 532 533void HeapSpaceRegion::dumpToStream(raw_ostream &os) const { 534 os << "HeapSpaceRegion"; 535} 536 537void UnknownSpaceRegion::dumpToStream(raw_ostream &os) const { 538 os << "UnknownSpaceRegion"; 539} 540 541void StackArgumentsSpaceRegion::dumpToStream(raw_ostream &os) const { 542 os << "StackArgumentsSpaceRegion"; 543} 544 545void StackLocalsSpaceRegion::dumpToStream(raw_ostream &os) const { 546 os << "StackLocalsSpaceRegion"; 547} 548 549void MemRegion::dumpPretty(raw_ostream &os) const { 550 return; 551} 552 553void VarRegion::dumpPretty(raw_ostream &os) const { 554 os << getDecl()->getName(); 555} 556 557void FieldRegion::dumpPretty(raw_ostream &os) const { 558 superRegion->dumpPretty(os); 559 os << "->" << getDecl(); 560} 561 562//===----------------------------------------------------------------------===// 563// MemRegionManager methods. 564//===----------------------------------------------------------------------===// 565 566template <typename REG> 567const REG *MemRegionManager::LazyAllocate(REG*& region) { 568 if (!region) { 569 region = (REG*) A.Allocate<REG>(); 570 new (region) REG(this); 571 } 572 573 return region; 574} 575 576template <typename REG, typename ARG> 577const REG *MemRegionManager::LazyAllocate(REG*& region, ARG a) { 578 if (!region) { 579 region = (REG*) A.Allocate<REG>(); 580 new (region) REG(this, a); 581 } 582 583 return region; 584} 585 586const StackLocalsSpaceRegion* 587MemRegionManager::getStackLocalsRegion(const StackFrameContext *STC) { 588 assert(STC); 589 StackLocalsSpaceRegion *&R = StackLocalsSpaceRegions[STC]; 590 591 if (R) 592 return R; 593 594 R = A.Allocate<StackLocalsSpaceRegion>(); 595 new (R) StackLocalsSpaceRegion(this, STC); 596 return R; 597} 598 599const StackArgumentsSpaceRegion * 600MemRegionManager::getStackArgumentsRegion(const StackFrameContext *STC) { 601 assert(STC); 602 StackArgumentsSpaceRegion *&R = StackArgumentsSpaceRegions[STC]; 603 604 if (R) 605 return R; 606 607 R = A.Allocate<StackArgumentsSpaceRegion>(); 608 new (R) StackArgumentsSpaceRegion(this, STC); 609 return R; 610} 611 612const GlobalsSpaceRegion 613*MemRegionManager::getGlobalsRegion(MemRegion::Kind K, 614 const CodeTextRegion *CR) { 615 if (!CR) { 616 if (K == MemRegion::GlobalSystemSpaceRegionKind) 617 return LazyAllocate(SystemGlobals); 618 if (K == MemRegion::GlobalImmutableSpaceRegionKind) 619 return LazyAllocate(ImmutableGlobals); 620 assert(K == MemRegion::GlobalInternalSpaceRegionKind); 621 return LazyAllocate(InternalGlobals); 622 } 623 624 assert(K == MemRegion::StaticGlobalSpaceRegionKind); 625 StaticGlobalSpaceRegion *&R = StaticsGlobalSpaceRegions[CR]; 626 if (R) 627 return R; 628 629 R = A.Allocate<StaticGlobalSpaceRegion>(); 630 new (R) StaticGlobalSpaceRegion(this, CR); 631 return R; 632} 633 634const HeapSpaceRegion *MemRegionManager::getHeapRegion() { 635 return LazyAllocate(heap); 636} 637 638const MemSpaceRegion *MemRegionManager::getUnknownRegion() { 639 return LazyAllocate(unknown); 640} 641 642const MemSpaceRegion *MemRegionManager::getCodeRegion() { 643 return LazyAllocate(code); 644} 645 646//===----------------------------------------------------------------------===// 647// Constructing regions. 648//===----------------------------------------------------------------------===// 649const StringRegion* MemRegionManager::getStringRegion(const StringLiteral* Str){ 650 return getSubRegion<StringRegion>(Str, getGlobalsRegion()); 651} 652 653const ObjCStringRegion * 654MemRegionManager::getObjCStringRegion(const ObjCStringLiteral* Str){ 655 return getSubRegion<ObjCStringRegion>(Str, getGlobalsRegion()); 656} 657 658/// Look through a chain of LocationContexts to either find the 659/// StackFrameContext that matches a DeclContext, or find a VarRegion 660/// for a variable captured by a block. 661static llvm::PointerUnion<const StackFrameContext *, const VarRegion *> 662getStackOrCaptureRegionForDeclContext(const LocationContext *LC, 663 const DeclContext *DC, 664 const VarDecl *VD) { 665 while (LC) { 666 if (const StackFrameContext *SFC = dyn_cast<StackFrameContext>(LC)) { 667 if (cast<DeclContext>(SFC->getDecl()) == DC) 668 return SFC; 669 } 670 if (const BlockInvocationContext *BC = 671 dyn_cast<BlockInvocationContext>(LC)) { 672 const BlockDataRegion *BR = 673 static_cast<const BlockDataRegion*>(BC->getContextData()); 674 // FIXME: This can be made more efficient. 675 for (BlockDataRegion::referenced_vars_iterator 676 I = BR->referenced_vars_begin(), 677 E = BR->referenced_vars_end(); I != E; ++I) { 678 if (const VarRegion *VR = dyn_cast<VarRegion>(I.getOriginalRegion())) 679 if (VR->getDecl() == VD) 680 return cast<VarRegion>(I.getCapturedRegion()); 681 } 682 } 683 684 LC = LC->getParent(); 685 } 686 return (const StackFrameContext*)0; 687} 688 689const VarRegion* MemRegionManager::getVarRegion(const VarDecl *D, 690 const LocationContext *LC) { 691 const MemRegion *sReg = 0; 692 693 if (D->hasGlobalStorage() && !D->isStaticLocal()) { 694 695 // First handle the globals defined in system headers. 696 if (C.getSourceManager().isInSystemHeader(D->getLocation())) { 697 // Whitelist the system globals which often DO GET modified, assume the 698 // rest are immutable. 699 if (D->getName().find("errno") != StringRef::npos) 700 sReg = getGlobalsRegion(MemRegion::GlobalSystemSpaceRegionKind); 701 else 702 sReg = getGlobalsRegion(MemRegion::GlobalImmutableSpaceRegionKind); 703 704 // Treat other globals as GlobalInternal unless they are constants. 705 } else { 706 QualType GQT = D->getType(); 707 const Type *GT = GQT.getTypePtrOrNull(); 708 // TODO: We could walk the complex types here and see if everything is 709 // constified. 710 if (GT && GQT.isConstQualified() && GT->isArithmeticType()) 711 sReg = getGlobalsRegion(MemRegion::GlobalImmutableSpaceRegionKind); 712 else 713 sReg = getGlobalsRegion(); 714 } 715 716 // Finally handle static locals. 717 } else { 718 // FIXME: Once we implement scope handling, we will need to properly lookup 719 // 'D' to the proper LocationContext. 720 const DeclContext *DC = D->getDeclContext(); 721 llvm::PointerUnion<const StackFrameContext *, const VarRegion *> V = 722 getStackOrCaptureRegionForDeclContext(LC, DC, D); 723 724 if (V.is<const VarRegion*>()) 725 return V.get<const VarRegion*>(); 726 727 const StackFrameContext *STC = V.get<const StackFrameContext*>(); 728 729 if (!STC) 730 sReg = getUnknownRegion(); 731 else { 732 if (D->hasLocalStorage()) { 733 sReg = isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) 734 ? static_cast<const MemRegion*>(getStackArgumentsRegion(STC)) 735 : static_cast<const MemRegion*>(getStackLocalsRegion(STC)); 736 } 737 else { 738 assert(D->isStaticLocal()); 739 const Decl *D = STC->getDecl(); 740 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) 741 sReg = getGlobalsRegion(MemRegion::StaticGlobalSpaceRegionKind, 742 getFunctionTextRegion(FD)); 743 else if (const BlockDecl *BD = dyn_cast<BlockDecl>(D)) { 744 const BlockTextRegion *BTR = 745 getBlockTextRegion(BD, 746 C.getCanonicalType(BD->getSignatureAsWritten()->getType()), 747 STC->getAnalysisDeclContext()); 748 sReg = getGlobalsRegion(MemRegion::StaticGlobalSpaceRegionKind, 749 BTR); 750 } 751 else { 752 // FIXME: For ObjC-methods, we need a new CodeTextRegion. For now 753 // just use the main global memspace. 754 sReg = getGlobalsRegion(); 755 } 756 } 757 } 758 } 759 760 return getSubRegion<VarRegion>(D, sReg); 761} 762 763const VarRegion *MemRegionManager::getVarRegion(const VarDecl *D, 764 const MemRegion *superR) { 765 return getSubRegion<VarRegion>(D, superR); 766} 767 768const BlockDataRegion * 769MemRegionManager::getBlockDataRegion(const BlockTextRegion *BC, 770 const LocationContext *LC) { 771 const MemRegion *sReg = 0; 772 const BlockDecl *BD = BC->getDecl(); 773 if (!BD->hasCaptures()) { 774 // This handles 'static' blocks. 775 sReg = getGlobalsRegion(MemRegion::GlobalImmutableSpaceRegionKind); 776 } 777 else { 778 if (LC) { 779 // FIXME: Once we implement scope handling, we want the parent region 780 // to be the scope. 781 const StackFrameContext *STC = LC->getCurrentStackFrame(); 782 assert(STC); 783 sReg = getStackLocalsRegion(STC); 784 } 785 else { 786 // We allow 'LC' to be NULL for cases where want BlockDataRegions 787 // without context-sensitivity. 788 sReg = getUnknownRegion(); 789 } 790 } 791 792 return getSubRegion<BlockDataRegion>(BC, LC, sReg); 793} 794 795const CompoundLiteralRegion* 796MemRegionManager::getCompoundLiteralRegion(const CompoundLiteralExpr *CL, 797 const LocationContext *LC) { 798 799 const MemRegion *sReg = 0; 800 801 if (CL->isFileScope()) 802 sReg = getGlobalsRegion(); 803 else { 804 const StackFrameContext *STC = LC->getCurrentStackFrame(); 805 assert(STC); 806 sReg = getStackLocalsRegion(STC); 807 } 808 809 return getSubRegion<CompoundLiteralRegion>(CL, sReg); 810} 811 812const ElementRegion* 813MemRegionManager::getElementRegion(QualType elementType, NonLoc Idx, 814 const MemRegion* superRegion, 815 ASTContext &Ctx){ 816 817 QualType T = Ctx.getCanonicalType(elementType).getUnqualifiedType(); 818 819 llvm::FoldingSetNodeID ID; 820 ElementRegion::ProfileRegion(ID, T, Idx, superRegion); 821 822 void *InsertPos; 823 MemRegion* data = Regions.FindNodeOrInsertPos(ID, InsertPos); 824 ElementRegion* R = cast_or_null<ElementRegion>(data); 825 826 if (!R) { 827 R = (ElementRegion*) A.Allocate<ElementRegion>(); 828 new (R) ElementRegion(T, Idx, superRegion); 829 Regions.InsertNode(R, InsertPos); 830 } 831 832 return R; 833} 834 835const FunctionTextRegion * 836MemRegionManager::getFunctionTextRegion(const FunctionDecl *FD) { 837 return getSubRegion<FunctionTextRegion>(FD, getCodeRegion()); 838} 839 840const BlockTextRegion * 841MemRegionManager::getBlockTextRegion(const BlockDecl *BD, CanQualType locTy, 842 AnalysisDeclContext *AC) { 843 return getSubRegion<BlockTextRegion>(BD, locTy, AC, getCodeRegion()); 844} 845 846 847/// getSymbolicRegion - Retrieve or create a "symbolic" memory region. 848const SymbolicRegion *MemRegionManager::getSymbolicRegion(SymbolRef sym) { 849 return getSubRegion<SymbolicRegion>(sym, getUnknownRegion()); 850} 851 852const SymbolicRegion *MemRegionManager::getSymbolicHeapRegion(SymbolRef Sym) { 853 return getSubRegion<SymbolicRegion>(Sym, getHeapRegion()); 854} 855 856const FieldRegion* 857MemRegionManager::getFieldRegion(const FieldDecl *d, 858 const MemRegion* superRegion){ 859 return getSubRegion<FieldRegion>(d, superRegion); 860} 861 862const ObjCIvarRegion* 863MemRegionManager::getObjCIvarRegion(const ObjCIvarDecl *d, 864 const MemRegion* superRegion) { 865 return getSubRegion<ObjCIvarRegion>(d, superRegion); 866} 867 868const CXXTempObjectRegion* 869MemRegionManager::getCXXTempObjectRegion(Expr const *E, 870 LocationContext const *LC) { 871 const StackFrameContext *SFC = LC->getCurrentStackFrame(); 872 assert(SFC); 873 return getSubRegion<CXXTempObjectRegion>(E, getStackLocalsRegion(SFC)); 874} 875 876const CXXBaseObjectRegion * 877MemRegionManager::getCXXBaseObjectRegion(const CXXRecordDecl *decl, 878 const MemRegion *superRegion) { 879 return getSubRegion<CXXBaseObjectRegion>(decl, superRegion); 880} 881 882const CXXThisRegion* 883MemRegionManager::getCXXThisRegion(QualType thisPointerTy, 884 const LocationContext *LC) { 885 const StackFrameContext *STC = LC->getCurrentStackFrame(); 886 assert(STC); 887 const PointerType *PT = thisPointerTy->getAs<PointerType>(); 888 assert(PT); 889 return getSubRegion<CXXThisRegion>(PT, getStackArgumentsRegion(STC)); 890} 891 892const AllocaRegion* 893MemRegionManager::getAllocaRegion(const Expr *E, unsigned cnt, 894 const LocationContext *LC) { 895 const StackFrameContext *STC = LC->getCurrentStackFrame(); 896 assert(STC); 897 return getSubRegion<AllocaRegion>(E, cnt, getStackLocalsRegion(STC)); 898} 899 900const MemSpaceRegion *MemRegion::getMemorySpace() const { 901 const MemRegion *R = this; 902 const SubRegion* SR = dyn_cast<SubRegion>(this); 903 904 while (SR) { 905 R = SR->getSuperRegion(); 906 SR = dyn_cast<SubRegion>(R); 907 } 908 909 return dyn_cast<MemSpaceRegion>(R); 910} 911 912bool MemRegion::hasStackStorage() const { 913 return isa<StackSpaceRegion>(getMemorySpace()); 914} 915 916bool MemRegion::hasStackNonParametersStorage() const { 917 return isa<StackLocalsSpaceRegion>(getMemorySpace()); 918} 919 920bool MemRegion::hasStackParametersStorage() const { 921 return isa<StackArgumentsSpaceRegion>(getMemorySpace()); 922} 923 924bool MemRegion::hasGlobalsOrParametersStorage() const { 925 const MemSpaceRegion *MS = getMemorySpace(); 926 return isa<StackArgumentsSpaceRegion>(MS) || 927 isa<GlobalsSpaceRegion>(MS); 928} 929 930// getBaseRegion strips away all elements and fields, and get the base region 931// of them. 932const MemRegion *MemRegion::getBaseRegion() const { 933 const MemRegion *R = this; 934 while (true) { 935 switch (R->getKind()) { 936 case MemRegion::ElementRegionKind: 937 case MemRegion::FieldRegionKind: 938 case MemRegion::ObjCIvarRegionKind: 939 case MemRegion::CXXBaseObjectRegionKind: 940 R = cast<SubRegion>(R)->getSuperRegion(); 941 continue; 942 default: 943 break; 944 } 945 break; 946 } 947 return R; 948} 949 950//===----------------------------------------------------------------------===// 951// View handling. 952//===----------------------------------------------------------------------===// 953 954const MemRegion *MemRegion::StripCasts() const { 955 const MemRegion *R = this; 956 while (true) { 957 if (const ElementRegion *ER = dyn_cast<ElementRegion>(R)) { 958 // FIXME: generalize. Essentially we want to strip away ElementRegions 959 // that were layered on a symbolic region because of casts. We only 960 // want to strip away ElementRegions, however, where the index is 0. 961 SVal index = ER->getIndex(); 962 if (nonloc::ConcreteInt *CI = dyn_cast<nonloc::ConcreteInt>(&index)) { 963 if (CI->getValue().getSExtValue() == 0) { 964 R = ER->getSuperRegion(); 965 continue; 966 } 967 } 968 } 969 break; 970 } 971 return R; 972} 973 974// FIXME: Merge with the implementation of the same method in Store.cpp 975static bool IsCompleteType(ASTContext &Ctx, QualType Ty) { 976 if (const RecordType *RT = Ty->getAs<RecordType>()) { 977 const RecordDecl *D = RT->getDecl(); 978 if (!D->getDefinition()) 979 return false; 980 } 981 982 return true; 983} 984 985RegionRawOffset ElementRegion::getAsArrayOffset() const { 986 CharUnits offset = CharUnits::Zero(); 987 const ElementRegion *ER = this; 988 const MemRegion *superR = NULL; 989 ASTContext &C = getContext(); 990 991 // FIXME: Handle multi-dimensional arrays. 992 993 while (ER) { 994 superR = ER->getSuperRegion(); 995 996 // FIXME: generalize to symbolic offsets. 997 SVal index = ER->getIndex(); 998 if (nonloc::ConcreteInt *CI = dyn_cast<nonloc::ConcreteInt>(&index)) { 999 // Update the offset. 1000 int64_t i = CI->getValue().getSExtValue(); 1001 1002 if (i != 0) { 1003 QualType elemType = ER->getElementType(); 1004 1005 // If we are pointing to an incomplete type, go no further. 1006 if (!IsCompleteType(C, elemType)) { 1007 superR = ER; 1008 break; 1009 } 1010 1011 CharUnits size = C.getTypeSizeInChars(elemType); 1012 offset += (i * size); 1013 } 1014 1015 // Go to the next ElementRegion (if any). 1016 ER = dyn_cast<ElementRegion>(superR); 1017 continue; 1018 } 1019 1020 return NULL; 1021 } 1022 1023 assert(superR && "super region cannot be NULL"); 1024 return RegionRawOffset(superR, offset); 1025} 1026 1027RegionOffset MemRegion::getAsOffset() const { 1028 const MemRegion *R = this; 1029 int64_t Offset = 0; 1030 1031 while (1) { 1032 switch (R->getKind()) { 1033 default: 1034 return RegionOffset(0); 1035 case SymbolicRegionKind: 1036 case AllocaRegionKind: 1037 case CompoundLiteralRegionKind: 1038 case CXXThisRegionKind: 1039 case StringRegionKind: 1040 case VarRegionKind: 1041 case CXXTempObjectRegionKind: 1042 goto Finish; 1043 case ElementRegionKind: { 1044 const ElementRegion *ER = cast<ElementRegion>(R); 1045 QualType EleTy = ER->getValueType(); 1046 1047 if (!IsCompleteType(getContext(), EleTy)) 1048 return RegionOffset(0); 1049 1050 SVal Index = ER->getIndex(); 1051 if (const nonloc::ConcreteInt *CI=dyn_cast<nonloc::ConcreteInt>(&Index)) { 1052 int64_t i = CI->getValue().getSExtValue(); 1053 CharUnits Size = getContext().getTypeSizeInChars(EleTy); 1054 Offset += i * Size.getQuantity() * 8; 1055 } else { 1056 // We cannot compute offset for non-concrete index. 1057 return RegionOffset(0); 1058 } 1059 R = ER->getSuperRegion(); 1060 break; 1061 } 1062 case FieldRegionKind: { 1063 const FieldRegion *FR = cast<FieldRegion>(R); 1064 const RecordDecl *RD = FR->getDecl()->getParent(); 1065 if (!RD->isCompleteDefinition()) 1066 // We cannot compute offset for incomplete type. 1067 return RegionOffset(0); 1068 // Get the field number. 1069 unsigned idx = 0; 1070 for (RecordDecl::field_iterator FI = RD->field_begin(), 1071 FE = RD->field_end(); FI != FE; ++FI, ++idx) 1072 if (FR->getDecl() == *FI) 1073 break; 1074 1075 const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD); 1076 // This is offset in bits. 1077 Offset += Layout.getFieldOffset(idx); 1078 R = FR->getSuperRegion(); 1079 break; 1080 } 1081 } 1082 } 1083 1084 Finish: 1085 return RegionOffset(R, Offset); 1086} 1087 1088//===----------------------------------------------------------------------===// 1089// BlockDataRegion 1090//===----------------------------------------------------------------------===// 1091 1092void BlockDataRegion::LazyInitializeReferencedVars() { 1093 if (ReferencedVars) 1094 return; 1095 1096 AnalysisDeclContext *AC = getCodeRegion()->getAnalysisDeclContext(); 1097 AnalysisDeclContext::referenced_decls_iterator I, E; 1098 llvm::tie(I, E) = AC->getReferencedBlockVars(BC->getDecl()); 1099 1100 if (I == E) { 1101 ReferencedVars = (void*) 0x1; 1102 return; 1103 } 1104 1105 MemRegionManager &MemMgr = *getMemRegionManager(); 1106 llvm::BumpPtrAllocator &A = MemMgr.getAllocator(); 1107 BumpVectorContext BC(A); 1108 1109 typedef BumpVector<const MemRegion*> VarVec; 1110 VarVec *BV = (VarVec*) A.Allocate<VarVec>(); 1111 new (BV) VarVec(BC, E - I); 1112 VarVec *BVOriginal = (VarVec*) A.Allocate<VarVec>(); 1113 new (BVOriginal) VarVec(BC, E - I); 1114 1115 for ( ; I != E; ++I) { 1116 const VarDecl *VD = *I; 1117 const VarRegion *VR = 0; 1118 const VarRegion *OriginalVR = 0; 1119 1120 if (!VD->getAttr<BlocksAttr>() && VD->hasLocalStorage()) { 1121 VR = MemMgr.getVarRegion(VD, this); 1122 OriginalVR = MemMgr.getVarRegion(VD, LC); 1123 } 1124 else { 1125 if (LC) { 1126 VR = MemMgr.getVarRegion(VD, LC); 1127 OriginalVR = VR; 1128 } 1129 else { 1130 VR = MemMgr.getVarRegion(VD, MemMgr.getUnknownRegion()); 1131 OriginalVR = MemMgr.getVarRegion(VD, LC); 1132 } 1133 } 1134 1135 assert(VR); 1136 assert(OriginalVR); 1137 BV->push_back(VR, BC); 1138 BVOriginal->push_back(OriginalVR, BC); 1139 } 1140 1141 ReferencedVars = BV; 1142 OriginalVars = BVOriginal; 1143} 1144 1145BlockDataRegion::referenced_vars_iterator 1146BlockDataRegion::referenced_vars_begin() const { 1147 const_cast<BlockDataRegion*>(this)->LazyInitializeReferencedVars(); 1148 1149 BumpVector<const MemRegion*> *Vec = 1150 static_cast<BumpVector<const MemRegion*>*>(ReferencedVars); 1151 1152 if (Vec == (void*) 0x1) 1153 return BlockDataRegion::referenced_vars_iterator(0, 0); 1154 1155 BumpVector<const MemRegion*> *VecOriginal = 1156 static_cast<BumpVector<const MemRegion*>*>(OriginalVars); 1157 1158 return BlockDataRegion::referenced_vars_iterator(Vec->begin(), 1159 VecOriginal->begin()); 1160} 1161 1162BlockDataRegion::referenced_vars_iterator 1163BlockDataRegion::referenced_vars_end() const { 1164 const_cast<BlockDataRegion*>(this)->LazyInitializeReferencedVars(); 1165 1166 BumpVector<const MemRegion*> *Vec = 1167 static_cast<BumpVector<const MemRegion*>*>(ReferencedVars); 1168 1169 if (Vec == (void*) 0x1) 1170 return BlockDataRegion::referenced_vars_iterator(0, 0); 1171 1172 BumpVector<const MemRegion*> *VecOriginal = 1173 static_cast<BumpVector<const MemRegion*>*>(OriginalVars); 1174 1175 return BlockDataRegion::referenced_vars_iterator(Vec->end(), 1176 VecOriginal->end()); 1177} 1178