Expr.cpp revision db2eb5abf4c082d1f0c5c45e39d8cd0300f81e38
1//===--- Expr.cpp - Expression AST Node Implementation --------------------===// 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 Expr class and subclasses. 11// 12//===----------------------------------------------------------------------===// 13 14#include "clang/AST/Expr.h" 15#include "clang/AST/ExprCXX.h" 16#include "clang/AST/APValue.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/AST/DeclObjC.h" 19#include "clang/AST/DeclCXX.h" 20#include "clang/AST/DeclTemplate.h" 21#include "clang/AST/RecordLayout.h" 22#include "clang/AST/StmtVisitor.h" 23#include "clang/Basic/Builtins.h" 24#include "clang/Basic/TargetInfo.h" 25#include "llvm/Support/ErrorHandling.h" 26#include "llvm/Support/raw_ostream.h" 27#include <algorithm> 28using namespace clang; 29 30//===----------------------------------------------------------------------===// 31// Primary Expressions. 32//===----------------------------------------------------------------------===// 33 34void ExplicitTemplateArgumentList::initializeFrom( 35 const TemplateArgumentListInfo &Info) { 36 LAngleLoc = Info.getLAngleLoc(); 37 RAngleLoc = Info.getRAngleLoc(); 38 NumTemplateArgs = Info.size(); 39 40 TemplateArgumentLoc *ArgBuffer = getTemplateArgs(); 41 for (unsigned i = 0; i != NumTemplateArgs; ++i) 42 new (&ArgBuffer[i]) TemplateArgumentLoc(Info[i]); 43} 44 45void ExplicitTemplateArgumentList::copyInto( 46 TemplateArgumentListInfo &Info) const { 47 Info.setLAngleLoc(LAngleLoc); 48 Info.setRAngleLoc(RAngleLoc); 49 for (unsigned I = 0; I != NumTemplateArgs; ++I) 50 Info.addArgument(getTemplateArgs()[I]); 51} 52 53std::size_t ExplicitTemplateArgumentList::sizeFor( 54 const TemplateArgumentListInfo &Info) { 55 return sizeof(ExplicitTemplateArgumentList) + 56 sizeof(TemplateArgumentLoc) * Info.size(); 57} 58 59void DeclRefExpr::computeDependence() { 60 TypeDependent = false; 61 ValueDependent = false; 62 63 NamedDecl *D = getDecl(); 64 65 // (TD) C++ [temp.dep.expr]p3: 66 // An id-expression is type-dependent if it contains: 67 // 68 // and 69 // 70 // (VD) C++ [temp.dep.constexpr]p2: 71 // An identifier is value-dependent if it is: 72 73 // (TD) - an identifier that was declared with dependent type 74 // (VD) - a name declared with a dependent type, 75 if (getType()->isDependentType()) { 76 TypeDependent = true; 77 ValueDependent = true; 78 } 79 // (TD) - a conversion-function-id that specifies a dependent type 80 else if (D->getDeclName().getNameKind() 81 == DeclarationName::CXXConversionFunctionName && 82 D->getDeclName().getCXXNameType()->isDependentType()) { 83 TypeDependent = true; 84 ValueDependent = true; 85 } 86 // (TD) - a template-id that is dependent, 87 else if (hasExplicitTemplateArgumentList() && 88 TemplateSpecializationType::anyDependentTemplateArguments( 89 getTemplateArgs(), 90 getNumTemplateArgs())) { 91 TypeDependent = true; 92 ValueDependent = true; 93 } 94 // (VD) - the name of a non-type template parameter, 95 else if (isa<NonTypeTemplateParmDecl>(D)) 96 ValueDependent = true; 97 // (VD) - a constant with integral or enumeration type and is 98 // initialized with an expression that is value-dependent. 99 else if (VarDecl *Var = dyn_cast<VarDecl>(D)) { 100 if (Var->getType()->isIntegralType() && 101 Var->getType().getCVRQualifiers() == Qualifiers::Const) { 102 if (const Expr *Init = Var->getAnyInitializer()) 103 if (Init->isValueDependent()) 104 ValueDependent = true; 105 } 106 } 107 // (TD) - a nested-name-specifier or a qualified-id that names a 108 // member of an unknown specialization. 109 // (handled by DependentScopeDeclRefExpr) 110} 111 112DeclRefExpr::DeclRefExpr(NestedNameSpecifier *Qualifier, 113 SourceRange QualifierRange, 114 ValueDecl *D, SourceLocation NameLoc, 115 const TemplateArgumentListInfo *TemplateArgs, 116 QualType T) 117 : Expr(DeclRefExprClass, T, false, false), 118 DecoratedD(D, 119 (Qualifier? HasQualifierFlag : 0) | 120 (TemplateArgs ? HasExplicitTemplateArgumentListFlag : 0)), 121 Loc(NameLoc) { 122 if (Qualifier) { 123 NameQualifier *NQ = getNameQualifier(); 124 NQ->NNS = Qualifier; 125 NQ->Range = QualifierRange; 126 } 127 128 if (TemplateArgs) 129 getExplicitTemplateArgumentList()->initializeFrom(*TemplateArgs); 130 131 computeDependence(); 132} 133 134DeclRefExpr *DeclRefExpr::Create(ASTContext &Context, 135 NestedNameSpecifier *Qualifier, 136 SourceRange QualifierRange, 137 ValueDecl *D, 138 SourceLocation NameLoc, 139 QualType T, 140 const TemplateArgumentListInfo *TemplateArgs) { 141 std::size_t Size = sizeof(DeclRefExpr); 142 if (Qualifier != 0) 143 Size += sizeof(NameQualifier); 144 145 if (TemplateArgs) 146 Size += ExplicitTemplateArgumentList::sizeFor(*TemplateArgs); 147 148 void *Mem = Context.Allocate(Size, llvm::alignof<DeclRefExpr>()); 149 return new (Mem) DeclRefExpr(Qualifier, QualifierRange, D, NameLoc, 150 TemplateArgs, T); 151} 152 153SourceRange DeclRefExpr::getSourceRange() const { 154 // FIXME: Does not handle multi-token names well, e.g., operator[]. 155 SourceRange R(Loc); 156 157 if (hasQualifier()) 158 R.setBegin(getQualifierRange().getBegin()); 159 if (hasExplicitTemplateArgumentList()) 160 R.setEnd(getRAngleLoc()); 161 return R; 162} 163 164// FIXME: Maybe this should use DeclPrinter with a special "print predefined 165// expr" policy instead. 166std::string PredefinedExpr::ComputeName(IdentType IT, const Decl *CurrentDecl) { 167 ASTContext &Context = CurrentDecl->getASTContext(); 168 169 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(CurrentDecl)) { 170 if (IT != PrettyFunction && IT != PrettyFunctionNoVirtual) 171 return FD->getNameAsString(); 172 173 llvm::SmallString<256> Name; 174 llvm::raw_svector_ostream Out(Name); 175 176 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) { 177 if (MD->isVirtual() && IT != PrettyFunctionNoVirtual) 178 Out << "virtual "; 179 if (MD->isStatic()) 180 Out << "static "; 181 } 182 183 PrintingPolicy Policy(Context.getLangOptions()); 184 185 std::string Proto = FD->getQualifiedNameAsString(Policy); 186 187 const FunctionType *AFT = FD->getType()->getAs<FunctionType>(); 188 const FunctionProtoType *FT = 0; 189 if (FD->hasWrittenPrototype()) 190 FT = dyn_cast<FunctionProtoType>(AFT); 191 192 Proto += "("; 193 if (FT) { 194 llvm::raw_string_ostream POut(Proto); 195 for (unsigned i = 0, e = FD->getNumParams(); i != e; ++i) { 196 if (i) POut << ", "; 197 std::string Param; 198 FD->getParamDecl(i)->getType().getAsStringInternal(Param, Policy); 199 POut << Param; 200 } 201 202 if (FT->isVariadic()) { 203 if (FD->getNumParams()) POut << ", "; 204 POut << "..."; 205 } 206 } 207 Proto += ")"; 208 209 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) { 210 Qualifiers ThisQuals = Qualifiers::fromCVRMask(MD->getTypeQualifiers()); 211 if (ThisQuals.hasConst()) 212 Proto += " const"; 213 if (ThisQuals.hasVolatile()) 214 Proto += " volatile"; 215 } 216 217 if (!isa<CXXConstructorDecl>(FD) && !isa<CXXDestructorDecl>(FD)) 218 AFT->getResultType().getAsStringInternal(Proto, Policy); 219 220 Out << Proto; 221 222 Out.flush(); 223 return Name.str().str(); 224 } 225 if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(CurrentDecl)) { 226 llvm::SmallString<256> Name; 227 llvm::raw_svector_ostream Out(Name); 228 Out << (MD->isInstanceMethod() ? '-' : '+'); 229 Out << '['; 230 231 // For incorrect code, there might not be an ObjCInterfaceDecl. Do 232 // a null check to avoid a crash. 233 if (const ObjCInterfaceDecl *ID = MD->getClassInterface()) 234 Out << ID->getNameAsString(); 235 236 if (const ObjCCategoryImplDecl *CID = 237 dyn_cast<ObjCCategoryImplDecl>(MD->getDeclContext())) { 238 Out << '('; 239 Out << CID->getNameAsString(); 240 Out << ')'; 241 } 242 Out << ' '; 243 Out << MD->getSelector().getAsString(); 244 Out << ']'; 245 246 Out.flush(); 247 return Name.str().str(); 248 } 249 if (isa<TranslationUnitDecl>(CurrentDecl) && IT == PrettyFunction) { 250 // __PRETTY_FUNCTION__ -> "top level", the others produce an empty string. 251 return "top level"; 252 } 253 return ""; 254} 255 256/// getValueAsApproximateDouble - This returns the value as an inaccurate 257/// double. Note that this may cause loss of precision, but is useful for 258/// debugging dumps, etc. 259double FloatingLiteral::getValueAsApproximateDouble() const { 260 llvm::APFloat V = getValue(); 261 bool ignored; 262 V.convert(llvm::APFloat::IEEEdouble, llvm::APFloat::rmNearestTiesToEven, 263 &ignored); 264 return V.convertToDouble(); 265} 266 267StringLiteral *StringLiteral::Create(ASTContext &C, const char *StrData, 268 unsigned ByteLength, bool Wide, 269 QualType Ty, 270 const SourceLocation *Loc, 271 unsigned NumStrs) { 272 // Allocate enough space for the StringLiteral plus an array of locations for 273 // any concatenated string tokens. 274 void *Mem = C.Allocate(sizeof(StringLiteral)+ 275 sizeof(SourceLocation)*(NumStrs-1), 276 llvm::alignof<StringLiteral>()); 277 StringLiteral *SL = new (Mem) StringLiteral(Ty); 278 279 // OPTIMIZE: could allocate this appended to the StringLiteral. 280 char *AStrData = new (C, 1) char[ByteLength]; 281 memcpy(AStrData, StrData, ByteLength); 282 SL->StrData = AStrData; 283 SL->ByteLength = ByteLength; 284 SL->IsWide = Wide; 285 SL->TokLocs[0] = Loc[0]; 286 SL->NumConcatenated = NumStrs; 287 288 if (NumStrs != 1) 289 memcpy(&SL->TokLocs[1], Loc+1, sizeof(SourceLocation)*(NumStrs-1)); 290 return SL; 291} 292 293StringLiteral *StringLiteral::CreateEmpty(ASTContext &C, unsigned NumStrs) { 294 void *Mem = C.Allocate(sizeof(StringLiteral)+ 295 sizeof(SourceLocation)*(NumStrs-1), 296 llvm::alignof<StringLiteral>()); 297 StringLiteral *SL = new (Mem) StringLiteral(QualType()); 298 SL->StrData = 0; 299 SL->ByteLength = 0; 300 SL->NumConcatenated = NumStrs; 301 return SL; 302} 303 304void StringLiteral::DoDestroy(ASTContext &C) { 305 C.Deallocate(const_cast<char*>(StrData)); 306 Expr::DoDestroy(C); 307} 308 309void StringLiteral::setString(ASTContext &C, llvm::StringRef Str) { 310 if (StrData) 311 C.Deallocate(const_cast<char*>(StrData)); 312 313 char *AStrData = new (C, 1) char[Str.size()]; 314 memcpy(AStrData, Str.data(), Str.size()); 315 StrData = AStrData; 316 ByteLength = Str.size(); 317} 318 319/// getOpcodeStr - Turn an Opcode enum value into the punctuation char it 320/// corresponds to, e.g. "sizeof" or "[pre]++". 321const char *UnaryOperator::getOpcodeStr(Opcode Op) { 322 switch (Op) { 323 default: assert(0 && "Unknown unary operator"); 324 case PostInc: return "++"; 325 case PostDec: return "--"; 326 case PreInc: return "++"; 327 case PreDec: return "--"; 328 case AddrOf: return "&"; 329 case Deref: return "*"; 330 case Plus: return "+"; 331 case Minus: return "-"; 332 case Not: return "~"; 333 case LNot: return "!"; 334 case Real: return "__real"; 335 case Imag: return "__imag"; 336 case Extension: return "__extension__"; 337 case OffsetOf: return "__builtin_offsetof"; 338 } 339} 340 341UnaryOperator::Opcode 342UnaryOperator::getOverloadedOpcode(OverloadedOperatorKind OO, bool Postfix) { 343 switch (OO) { 344 default: assert(false && "No unary operator for overloaded function"); 345 case OO_PlusPlus: return Postfix ? PostInc : PreInc; 346 case OO_MinusMinus: return Postfix ? PostDec : PreDec; 347 case OO_Amp: return AddrOf; 348 case OO_Star: return Deref; 349 case OO_Plus: return Plus; 350 case OO_Minus: return Minus; 351 case OO_Tilde: return Not; 352 case OO_Exclaim: return LNot; 353 } 354} 355 356OverloadedOperatorKind UnaryOperator::getOverloadedOperator(Opcode Opc) { 357 switch (Opc) { 358 case PostInc: case PreInc: return OO_PlusPlus; 359 case PostDec: case PreDec: return OO_MinusMinus; 360 case AddrOf: return OO_Amp; 361 case Deref: return OO_Star; 362 case Plus: return OO_Plus; 363 case Minus: return OO_Minus; 364 case Not: return OO_Tilde; 365 case LNot: return OO_Exclaim; 366 default: return OO_None; 367 } 368} 369 370 371//===----------------------------------------------------------------------===// 372// Postfix Operators. 373//===----------------------------------------------------------------------===// 374 375CallExpr::CallExpr(ASTContext& C, StmtClass SC, Expr *fn, Expr **args, 376 unsigned numargs, QualType t, SourceLocation rparenloc) 377 : Expr(SC, t, 378 fn->isTypeDependent() || hasAnyTypeDependentArguments(args, numargs), 379 fn->isValueDependent() || hasAnyValueDependentArguments(args,numargs)), 380 NumArgs(numargs) { 381 382 SubExprs = new (C) Stmt*[numargs+1]; 383 SubExprs[FN] = fn; 384 for (unsigned i = 0; i != numargs; ++i) 385 SubExprs[i+ARGS_START] = args[i]; 386 387 RParenLoc = rparenloc; 388} 389 390CallExpr::CallExpr(ASTContext& C, Expr *fn, Expr **args, unsigned numargs, 391 QualType t, SourceLocation rparenloc) 392 : Expr(CallExprClass, t, 393 fn->isTypeDependent() || hasAnyTypeDependentArguments(args, numargs), 394 fn->isValueDependent() || hasAnyValueDependentArguments(args,numargs)), 395 NumArgs(numargs) { 396 397 SubExprs = new (C) Stmt*[numargs+1]; 398 SubExprs[FN] = fn; 399 for (unsigned i = 0; i != numargs; ++i) 400 SubExprs[i+ARGS_START] = args[i]; 401 402 RParenLoc = rparenloc; 403} 404 405CallExpr::CallExpr(ASTContext &C, StmtClass SC, EmptyShell Empty) 406 : Expr(SC, Empty), SubExprs(0), NumArgs(0) { 407 SubExprs = new (C) Stmt*[1]; 408} 409 410void CallExpr::DoDestroy(ASTContext& C) { 411 DestroyChildren(C); 412 if (SubExprs) C.Deallocate(SubExprs); 413 this->~CallExpr(); 414 C.Deallocate(this); 415} 416 417Decl *CallExpr::getCalleeDecl() { 418 Expr *CEE = getCallee()->IgnoreParenCasts(); 419 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) 420 return DRE->getDecl(); 421 if (MemberExpr *ME = dyn_cast<MemberExpr>(CEE)) 422 return ME->getMemberDecl(); 423 424 return 0; 425} 426 427FunctionDecl *CallExpr::getDirectCallee() { 428 return dyn_cast_or_null<FunctionDecl>(getCalleeDecl()); 429} 430 431/// setNumArgs - This changes the number of arguments present in this call. 432/// Any orphaned expressions are deleted by this, and any new operands are set 433/// to null. 434void CallExpr::setNumArgs(ASTContext& C, unsigned NumArgs) { 435 // No change, just return. 436 if (NumArgs == getNumArgs()) return; 437 438 // If shrinking # arguments, just delete the extras and forgot them. 439 if (NumArgs < getNumArgs()) { 440 for (unsigned i = NumArgs, e = getNumArgs(); i != e; ++i) 441 getArg(i)->Destroy(C); 442 this->NumArgs = NumArgs; 443 return; 444 } 445 446 // Otherwise, we are growing the # arguments. New an bigger argument array. 447 Stmt **NewSubExprs = new (C) Stmt*[NumArgs+1]; 448 // Copy over args. 449 for (unsigned i = 0; i != getNumArgs()+ARGS_START; ++i) 450 NewSubExprs[i] = SubExprs[i]; 451 // Null out new args. 452 for (unsigned i = getNumArgs()+ARGS_START; i != NumArgs+ARGS_START; ++i) 453 NewSubExprs[i] = 0; 454 455 if (SubExprs) C.Deallocate(SubExprs); 456 SubExprs = NewSubExprs; 457 this->NumArgs = NumArgs; 458} 459 460/// isBuiltinCall - If this is a call to a builtin, return the builtin ID. If 461/// not, return 0. 462unsigned CallExpr::isBuiltinCall(ASTContext &Context) const { 463 // All simple function calls (e.g. func()) are implicitly cast to pointer to 464 // function. As a result, we try and obtain the DeclRefExpr from the 465 // ImplicitCastExpr. 466 const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(getCallee()); 467 if (!ICE) // FIXME: deal with more complex calls (e.g. (func)(), (*func)()). 468 return 0; 469 470 const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ICE->getSubExpr()); 471 if (!DRE) 472 return 0; 473 474 const FunctionDecl *FDecl = dyn_cast<FunctionDecl>(DRE->getDecl()); 475 if (!FDecl) 476 return 0; 477 478 if (!FDecl->getIdentifier()) 479 return 0; 480 481 return FDecl->getBuiltinID(); 482} 483 484QualType CallExpr::getCallReturnType() const { 485 QualType CalleeType = getCallee()->getType(); 486 if (const PointerType *FnTypePtr = CalleeType->getAs<PointerType>()) 487 CalleeType = FnTypePtr->getPointeeType(); 488 else if (const BlockPointerType *BPT = CalleeType->getAs<BlockPointerType>()) 489 CalleeType = BPT->getPointeeType(); 490 491 const FunctionType *FnType = CalleeType->getAs<FunctionType>(); 492 return FnType->getResultType(); 493} 494 495MemberExpr *MemberExpr::Create(ASTContext &C, Expr *base, bool isarrow, 496 NestedNameSpecifier *qual, 497 SourceRange qualrange, 498 ValueDecl *memberdecl, 499 NamedDecl *founddecl, 500 SourceLocation l, 501 const TemplateArgumentListInfo *targs, 502 QualType ty) { 503 std::size_t Size = sizeof(MemberExpr); 504 505 bool hasQualOrFound = (qual != 0 || founddecl != memberdecl); 506 if (hasQualOrFound) 507 Size += sizeof(MemberNameQualifier); 508 509 if (targs) 510 Size += ExplicitTemplateArgumentList::sizeFor(*targs); 511 512 void *Mem = C.Allocate(Size, llvm::alignof<MemberExpr>()); 513 MemberExpr *E = new (Mem) MemberExpr(base, isarrow, memberdecl, l, ty); 514 515 if (hasQualOrFound) { 516 if (qual && qual->isDependent()) { 517 E->setValueDependent(true); 518 E->setTypeDependent(true); 519 } 520 E->HasQualifierOrFoundDecl = true; 521 522 MemberNameQualifier *NQ = E->getMemberQualifier(); 523 NQ->NNS = qual; 524 NQ->Range = qualrange; 525 NQ->FoundDecl = founddecl; 526 } 527 528 if (targs) { 529 E->HasExplicitTemplateArgumentList = true; 530 E->getExplicitTemplateArgumentList()->initializeFrom(*targs); 531 } 532 533 return E; 534} 535 536const char *CastExpr::getCastKindName() const { 537 switch (getCastKind()) { 538 case CastExpr::CK_Unknown: 539 return "Unknown"; 540 case CastExpr::CK_BitCast: 541 return "BitCast"; 542 case CastExpr::CK_NoOp: 543 return "NoOp"; 544 case CastExpr::CK_BaseToDerived: 545 return "BaseToDerived"; 546 case CastExpr::CK_DerivedToBase: 547 return "DerivedToBase"; 548 case CastExpr::CK_UncheckedDerivedToBase: 549 return "UncheckedDerivedToBase"; 550 case CastExpr::CK_Dynamic: 551 return "Dynamic"; 552 case CastExpr::CK_ToUnion: 553 return "ToUnion"; 554 case CastExpr::CK_ArrayToPointerDecay: 555 return "ArrayToPointerDecay"; 556 case CastExpr::CK_FunctionToPointerDecay: 557 return "FunctionToPointerDecay"; 558 case CastExpr::CK_NullToMemberPointer: 559 return "NullToMemberPointer"; 560 case CastExpr::CK_BaseToDerivedMemberPointer: 561 return "BaseToDerivedMemberPointer"; 562 case CastExpr::CK_DerivedToBaseMemberPointer: 563 return "DerivedToBaseMemberPointer"; 564 case CastExpr::CK_UserDefinedConversion: 565 return "UserDefinedConversion"; 566 case CastExpr::CK_ConstructorConversion: 567 return "ConstructorConversion"; 568 case CastExpr::CK_IntegralToPointer: 569 return "IntegralToPointer"; 570 case CastExpr::CK_PointerToIntegral: 571 return "PointerToIntegral"; 572 case CastExpr::CK_ToVoid: 573 return "ToVoid"; 574 case CastExpr::CK_VectorSplat: 575 return "VectorSplat"; 576 case CastExpr::CK_IntegralCast: 577 return "IntegralCast"; 578 case CastExpr::CK_IntegralToFloating: 579 return "IntegralToFloating"; 580 case CastExpr::CK_FloatingToIntegral: 581 return "FloatingToIntegral"; 582 case CastExpr::CK_FloatingCast: 583 return "FloatingCast"; 584 case CastExpr::CK_MemberPointerToBoolean: 585 return "MemberPointerToBoolean"; 586 case CastExpr::CK_AnyPointerToObjCPointerCast: 587 return "AnyPointerToObjCPointerCast"; 588 case CastExpr::CK_AnyPointerToBlockPointerCast: 589 return "AnyPointerToBlockPointerCast"; 590 } 591 592 assert(0 && "Unhandled cast kind!"); 593 return 0; 594} 595 596Expr *CastExpr::getSubExprAsWritten() { 597 Expr *SubExpr = 0; 598 CastExpr *E = this; 599 do { 600 SubExpr = E->getSubExpr(); 601 602 // Skip any temporary bindings; they're implicit. 603 if (CXXBindTemporaryExpr *Binder = dyn_cast<CXXBindTemporaryExpr>(SubExpr)) 604 SubExpr = Binder->getSubExpr(); 605 606 // Conversions by constructor and conversion functions have a 607 // subexpression describing the call; strip it off. 608 if (E->getCastKind() == CastExpr::CK_ConstructorConversion) 609 SubExpr = cast<CXXConstructExpr>(SubExpr)->getArg(0); 610 else if (E->getCastKind() == CastExpr::CK_UserDefinedConversion) 611 SubExpr = cast<CXXMemberCallExpr>(SubExpr)->getImplicitObjectArgument(); 612 613 // If the subexpression we're left with is an implicit cast, look 614 // through that, too. 615 } while ((E = dyn_cast<ImplicitCastExpr>(SubExpr))); 616 617 return SubExpr; 618} 619 620/// getOpcodeStr - Turn an Opcode enum value into the punctuation char it 621/// corresponds to, e.g. "<<=". 622const char *BinaryOperator::getOpcodeStr(Opcode Op) { 623 switch (Op) { 624 case PtrMemD: return ".*"; 625 case PtrMemI: return "->*"; 626 case Mul: return "*"; 627 case Div: return "/"; 628 case Rem: return "%"; 629 case Add: return "+"; 630 case Sub: return "-"; 631 case Shl: return "<<"; 632 case Shr: return ">>"; 633 case LT: return "<"; 634 case GT: return ">"; 635 case LE: return "<="; 636 case GE: return ">="; 637 case EQ: return "=="; 638 case NE: return "!="; 639 case And: return "&"; 640 case Xor: return "^"; 641 case Or: return "|"; 642 case LAnd: return "&&"; 643 case LOr: return "||"; 644 case Assign: return "="; 645 case MulAssign: return "*="; 646 case DivAssign: return "/="; 647 case RemAssign: return "%="; 648 case AddAssign: return "+="; 649 case SubAssign: return "-="; 650 case ShlAssign: return "<<="; 651 case ShrAssign: return ">>="; 652 case AndAssign: return "&="; 653 case XorAssign: return "^="; 654 case OrAssign: return "|="; 655 case Comma: return ","; 656 } 657 658 return ""; 659} 660 661BinaryOperator::Opcode 662BinaryOperator::getOverloadedOpcode(OverloadedOperatorKind OO) { 663 switch (OO) { 664 default: assert(false && "Not an overloadable binary operator"); 665 case OO_Plus: return Add; 666 case OO_Minus: return Sub; 667 case OO_Star: return Mul; 668 case OO_Slash: return Div; 669 case OO_Percent: return Rem; 670 case OO_Caret: return Xor; 671 case OO_Amp: return And; 672 case OO_Pipe: return Or; 673 case OO_Equal: return Assign; 674 case OO_Less: return LT; 675 case OO_Greater: return GT; 676 case OO_PlusEqual: return AddAssign; 677 case OO_MinusEqual: return SubAssign; 678 case OO_StarEqual: return MulAssign; 679 case OO_SlashEqual: return DivAssign; 680 case OO_PercentEqual: return RemAssign; 681 case OO_CaretEqual: return XorAssign; 682 case OO_AmpEqual: return AndAssign; 683 case OO_PipeEqual: return OrAssign; 684 case OO_LessLess: return Shl; 685 case OO_GreaterGreater: return Shr; 686 case OO_LessLessEqual: return ShlAssign; 687 case OO_GreaterGreaterEqual: return ShrAssign; 688 case OO_EqualEqual: return EQ; 689 case OO_ExclaimEqual: return NE; 690 case OO_LessEqual: return LE; 691 case OO_GreaterEqual: return GE; 692 case OO_AmpAmp: return LAnd; 693 case OO_PipePipe: return LOr; 694 case OO_Comma: return Comma; 695 case OO_ArrowStar: return PtrMemI; 696 } 697} 698 699OverloadedOperatorKind BinaryOperator::getOverloadedOperator(Opcode Opc) { 700 static const OverloadedOperatorKind OverOps[] = { 701 /* .* Cannot be overloaded */OO_None, OO_ArrowStar, 702 OO_Star, OO_Slash, OO_Percent, 703 OO_Plus, OO_Minus, 704 OO_LessLess, OO_GreaterGreater, 705 OO_Less, OO_Greater, OO_LessEqual, OO_GreaterEqual, 706 OO_EqualEqual, OO_ExclaimEqual, 707 OO_Amp, 708 OO_Caret, 709 OO_Pipe, 710 OO_AmpAmp, 711 OO_PipePipe, 712 OO_Equal, OO_StarEqual, 713 OO_SlashEqual, OO_PercentEqual, 714 OO_PlusEqual, OO_MinusEqual, 715 OO_LessLessEqual, OO_GreaterGreaterEqual, 716 OO_AmpEqual, OO_CaretEqual, 717 OO_PipeEqual, 718 OO_Comma 719 }; 720 return OverOps[Opc]; 721} 722 723InitListExpr::InitListExpr(SourceLocation lbraceloc, 724 Expr **initExprs, unsigned numInits, 725 SourceLocation rbraceloc) 726 : Expr(InitListExprClass, QualType(), false, false), 727 LBraceLoc(lbraceloc), RBraceLoc(rbraceloc), SyntacticForm(0), 728 UnionFieldInit(0), HadArrayRangeDesignator(false) 729{ 730 for (unsigned I = 0; I != numInits; ++I) { 731 if (initExprs[I]->isTypeDependent()) 732 TypeDependent = true; 733 if (initExprs[I]->isValueDependent()) 734 ValueDependent = true; 735 } 736 737 InitExprs.insert(InitExprs.end(), initExprs, initExprs+numInits); 738} 739 740void InitListExpr::reserveInits(unsigned NumInits) { 741 if (NumInits > InitExprs.size()) 742 InitExprs.reserve(NumInits); 743} 744 745void InitListExpr::resizeInits(ASTContext &Context, unsigned NumInits) { 746 for (unsigned Idx = NumInits, LastIdx = InitExprs.size(); 747 Idx < LastIdx; ++Idx) 748 InitExprs[Idx]->Destroy(Context); 749 InitExprs.resize(NumInits, 0); 750} 751 752Expr *InitListExpr::updateInit(unsigned Init, Expr *expr) { 753 if (Init >= InitExprs.size()) { 754 InitExprs.insert(InitExprs.end(), Init - InitExprs.size() + 1, 0); 755 InitExprs.back() = expr; 756 return 0; 757 } 758 759 Expr *Result = cast_or_null<Expr>(InitExprs[Init]); 760 InitExprs[Init] = expr; 761 return Result; 762} 763 764/// getFunctionType - Return the underlying function type for this block. 765/// 766const FunctionType *BlockExpr::getFunctionType() const { 767 return getType()->getAs<BlockPointerType>()-> 768 getPointeeType()->getAs<FunctionType>(); 769} 770 771SourceLocation BlockExpr::getCaretLocation() const { 772 return TheBlock->getCaretLocation(); 773} 774const Stmt *BlockExpr::getBody() const { 775 return TheBlock->getBody(); 776} 777Stmt *BlockExpr::getBody() { 778 return TheBlock->getBody(); 779} 780 781 782//===----------------------------------------------------------------------===// 783// Generic Expression Routines 784//===----------------------------------------------------------------------===// 785 786/// isUnusedResultAWarning - Return true if this immediate expression should 787/// be warned about if the result is unused. If so, fill in Loc and Ranges 788/// with location to warn on and the source range[s] to report with the 789/// warning. 790bool Expr::isUnusedResultAWarning(SourceLocation &Loc, SourceRange &R1, 791 SourceRange &R2, ASTContext &Ctx) const { 792 // Don't warn if the expr is type dependent. The type could end up 793 // instantiating to void. 794 if (isTypeDependent()) 795 return false; 796 797 switch (getStmtClass()) { 798 default: 799 if (getType()->isVoidType()) 800 return false; 801 Loc = getExprLoc(); 802 R1 = getSourceRange(); 803 return true; 804 case ParenExprClass: 805 return cast<ParenExpr>(this)->getSubExpr()-> 806 isUnusedResultAWarning(Loc, R1, R2, Ctx); 807 case UnaryOperatorClass: { 808 const UnaryOperator *UO = cast<UnaryOperator>(this); 809 810 switch (UO->getOpcode()) { 811 default: break; 812 case UnaryOperator::PostInc: 813 case UnaryOperator::PostDec: 814 case UnaryOperator::PreInc: 815 case UnaryOperator::PreDec: // ++/-- 816 return false; // Not a warning. 817 case UnaryOperator::Deref: 818 // Dereferencing a volatile pointer is a side-effect. 819 if (Ctx.getCanonicalType(getType()).isVolatileQualified()) 820 return false; 821 break; 822 case UnaryOperator::Real: 823 case UnaryOperator::Imag: 824 // accessing a piece of a volatile complex is a side-effect. 825 if (Ctx.getCanonicalType(UO->getSubExpr()->getType()) 826 .isVolatileQualified()) 827 return false; 828 break; 829 case UnaryOperator::Extension: 830 return UO->getSubExpr()->isUnusedResultAWarning(Loc, R1, R2, Ctx); 831 } 832 Loc = UO->getOperatorLoc(); 833 R1 = UO->getSubExpr()->getSourceRange(); 834 return true; 835 } 836 case BinaryOperatorClass: { 837 const BinaryOperator *BO = cast<BinaryOperator>(this); 838 // Consider comma to have side effects if the LHS or RHS does. 839 if (BO->getOpcode() == BinaryOperator::Comma) { 840 // ((foo = <blah>), 0) is an idiom for hiding the result (and 841 // lvalue-ness) of an assignment written in a macro. 842 if (IntegerLiteral *IE = 843 dyn_cast<IntegerLiteral>(BO->getRHS()->IgnoreParens())) 844 if (IE->getValue() == 0) 845 return false; 846 847 return (BO->getLHS()->isUnusedResultAWarning(Loc, R1, R2, Ctx) || 848 BO->getRHS()->isUnusedResultAWarning(Loc, R1, R2, Ctx)); 849 } 850 851 if (BO->isAssignmentOp()) 852 return false; 853 Loc = BO->getOperatorLoc(); 854 R1 = BO->getLHS()->getSourceRange(); 855 R2 = BO->getRHS()->getSourceRange(); 856 return true; 857 } 858 case CompoundAssignOperatorClass: 859 return false; 860 861 case ConditionalOperatorClass: { 862 // The condition must be evaluated, but if either the LHS or RHS is a 863 // warning, warn about them. 864 const ConditionalOperator *Exp = cast<ConditionalOperator>(this); 865 if (Exp->getLHS() && 866 Exp->getLHS()->isUnusedResultAWarning(Loc, R1, R2, Ctx)) 867 return true; 868 return Exp->getRHS()->isUnusedResultAWarning(Loc, R1, R2, Ctx); 869 } 870 871 case MemberExprClass: 872 // If the base pointer or element is to a volatile pointer/field, accessing 873 // it is a side effect. 874 if (Ctx.getCanonicalType(getType()).isVolatileQualified()) 875 return false; 876 Loc = cast<MemberExpr>(this)->getMemberLoc(); 877 R1 = SourceRange(Loc, Loc); 878 R2 = cast<MemberExpr>(this)->getBase()->getSourceRange(); 879 return true; 880 881 case ArraySubscriptExprClass: 882 // If the base pointer or element is to a volatile pointer/field, accessing 883 // it is a side effect. 884 if (Ctx.getCanonicalType(getType()).isVolatileQualified()) 885 return false; 886 Loc = cast<ArraySubscriptExpr>(this)->getRBracketLoc(); 887 R1 = cast<ArraySubscriptExpr>(this)->getLHS()->getSourceRange(); 888 R2 = cast<ArraySubscriptExpr>(this)->getRHS()->getSourceRange(); 889 return true; 890 891 case CallExprClass: 892 case CXXOperatorCallExprClass: 893 case CXXMemberCallExprClass: { 894 // If this is a direct call, get the callee. 895 const CallExpr *CE = cast<CallExpr>(this); 896 if (const Decl *FD = CE->getCalleeDecl()) { 897 // If the callee has attribute pure, const, or warn_unused_result, warn 898 // about it. void foo() { strlen("bar"); } should warn. 899 // 900 // Note: If new cases are added here, DiagnoseUnusedExprResult should be 901 // updated to match for QoI. 902 if (FD->getAttr<WarnUnusedResultAttr>() || 903 FD->getAttr<PureAttr>() || FD->getAttr<ConstAttr>()) { 904 Loc = CE->getCallee()->getLocStart(); 905 R1 = CE->getCallee()->getSourceRange(); 906 907 if (unsigned NumArgs = CE->getNumArgs()) 908 R2 = SourceRange(CE->getArg(0)->getLocStart(), 909 CE->getArg(NumArgs-1)->getLocEnd()); 910 return true; 911 } 912 } 913 return false; 914 } 915 916 case CXXTemporaryObjectExprClass: 917 case CXXConstructExprClass: 918 return false; 919 920 case ObjCMessageExprClass: { 921 const ObjCMessageExpr *ME = cast<ObjCMessageExpr>(this); 922 const ObjCMethodDecl *MD = ME->getMethodDecl(); 923 if (MD && MD->getAttr<WarnUnusedResultAttr>()) { 924 Loc = getExprLoc(); 925 return true; 926 } 927 return false; 928 } 929 930 case ObjCImplicitSetterGetterRefExprClass: { // Dot syntax for message send. 931#if 0 932 const ObjCImplicitSetterGetterRefExpr *Ref = 933 cast<ObjCImplicitSetterGetterRefExpr>(this); 934 // FIXME: We really want the location of the '.' here. 935 Loc = Ref->getLocation(); 936 R1 = SourceRange(Ref->getLocation(), Ref->getLocation()); 937 if (Ref->getBase()) 938 R2 = Ref->getBase()->getSourceRange(); 939#else 940 Loc = getExprLoc(); 941 R1 = getSourceRange(); 942#endif 943 return true; 944 } 945 case StmtExprClass: { 946 // Statement exprs don't logically have side effects themselves, but are 947 // sometimes used in macros in ways that give them a type that is unused. 948 // For example ({ blah; foo(); }) will end up with a type if foo has a type. 949 // however, if the result of the stmt expr is dead, we don't want to emit a 950 // warning. 951 const CompoundStmt *CS = cast<StmtExpr>(this)->getSubStmt(); 952 if (!CS->body_empty()) 953 if (const Expr *E = dyn_cast<Expr>(CS->body_back())) 954 return E->isUnusedResultAWarning(Loc, R1, R2, Ctx); 955 956 if (getType()->isVoidType()) 957 return false; 958 Loc = cast<StmtExpr>(this)->getLParenLoc(); 959 R1 = getSourceRange(); 960 return true; 961 } 962 case CStyleCastExprClass: 963 // If this is an explicit cast to void, allow it. People do this when they 964 // think they know what they're doing :). 965 if (getType()->isVoidType()) 966 return false; 967 Loc = cast<CStyleCastExpr>(this)->getLParenLoc(); 968 R1 = cast<CStyleCastExpr>(this)->getSubExpr()->getSourceRange(); 969 return true; 970 case CXXFunctionalCastExprClass: { 971 if (getType()->isVoidType()) 972 return false; 973 const CastExpr *CE = cast<CastExpr>(this); 974 975 // If this is a cast to void or a constructor conversion, check the operand. 976 // Otherwise, the result of the cast is unused. 977 if (CE->getCastKind() == CastExpr::CK_ToVoid || 978 CE->getCastKind() == CastExpr::CK_ConstructorConversion) 979 return (cast<CastExpr>(this)->getSubExpr() 980 ->isUnusedResultAWarning(Loc, R1, R2, Ctx)); 981 Loc = cast<CXXFunctionalCastExpr>(this)->getTypeBeginLoc(); 982 R1 = cast<CXXFunctionalCastExpr>(this)->getSubExpr()->getSourceRange(); 983 return true; 984 } 985 986 case ImplicitCastExprClass: 987 // Check the operand, since implicit casts are inserted by Sema 988 return (cast<ImplicitCastExpr>(this) 989 ->getSubExpr()->isUnusedResultAWarning(Loc, R1, R2, Ctx)); 990 991 case CXXDefaultArgExprClass: 992 return (cast<CXXDefaultArgExpr>(this) 993 ->getExpr()->isUnusedResultAWarning(Loc, R1, R2, Ctx)); 994 995 case CXXNewExprClass: 996 // FIXME: In theory, there might be new expressions that don't have side 997 // effects (e.g. a placement new with an uninitialized POD). 998 case CXXDeleteExprClass: 999 return false; 1000 case CXXBindTemporaryExprClass: 1001 return (cast<CXXBindTemporaryExpr>(this) 1002 ->getSubExpr()->isUnusedResultAWarning(Loc, R1, R2, Ctx)); 1003 case CXXExprWithTemporariesClass: 1004 return (cast<CXXExprWithTemporaries>(this) 1005 ->getSubExpr()->isUnusedResultAWarning(Loc, R1, R2, Ctx)); 1006 } 1007} 1008 1009/// DeclCanBeLvalue - Determine whether the given declaration can be 1010/// an lvalue. This is a helper routine for isLvalue. 1011static bool DeclCanBeLvalue(const NamedDecl *Decl, ASTContext &Ctx) { 1012 // C++ [temp.param]p6: 1013 // A non-type non-reference template-parameter is not an lvalue. 1014 if (const NonTypeTemplateParmDecl *NTTParm 1015 = dyn_cast<NonTypeTemplateParmDecl>(Decl)) 1016 return NTTParm->getType()->isReferenceType(); 1017 1018 return isa<VarDecl>(Decl) || isa<FieldDecl>(Decl) || 1019 // C++ 3.10p2: An lvalue refers to an object or function. 1020 (Ctx.getLangOptions().CPlusPlus && 1021 (isa<FunctionDecl>(Decl) || isa<FunctionTemplateDecl>(Decl))); 1022} 1023 1024/// isLvalue - C99 6.3.2.1: an lvalue is an expression with an object type or an 1025/// incomplete type other than void. Nonarray expressions that can be lvalues: 1026/// - name, where name must be a variable 1027/// - e[i] 1028/// - (e), where e must be an lvalue 1029/// - e.name, where e must be an lvalue 1030/// - e->name 1031/// - *e, the type of e cannot be a function type 1032/// - string-constant 1033/// - (__real__ e) and (__imag__ e) where e is an lvalue [GNU extension] 1034/// - reference type [C++ [expr]] 1035/// 1036Expr::isLvalueResult Expr::isLvalue(ASTContext &Ctx) const { 1037 assert(!TR->isReferenceType() && "Expressions can't have reference type."); 1038 1039 isLvalueResult Res = isLvalueInternal(Ctx); 1040 if (Res != LV_Valid || Ctx.getLangOptions().CPlusPlus) 1041 return Res; 1042 1043 // first, check the type (C99 6.3.2.1). Expressions with function 1044 // type in C are not lvalues, but they can be lvalues in C++. 1045 if (TR->isFunctionType() || TR == Ctx.OverloadTy) 1046 return LV_NotObjectType; 1047 1048 // Allow qualified void which is an incomplete type other than void (yuck). 1049 if (TR->isVoidType() && !Ctx.getCanonicalType(TR).hasQualifiers()) 1050 return LV_IncompleteVoidType; 1051 1052 return LV_Valid; 1053} 1054 1055// Check whether the expression can be sanely treated like an l-value 1056Expr::isLvalueResult Expr::isLvalueInternal(ASTContext &Ctx) const { 1057 switch (getStmtClass()) { 1058 case ObjCIsaExprClass: 1059 case StringLiteralClass: // C99 6.5.1p4 1060 case ObjCEncodeExprClass: // @encode behaves like its string in every way. 1061 return LV_Valid; 1062 case ArraySubscriptExprClass: // C99 6.5.3p4 (e1[e2] == (*((e1)+(e2)))) 1063 // For vectors, make sure base is an lvalue (i.e. not a function call). 1064 if (cast<ArraySubscriptExpr>(this)->getBase()->getType()->isVectorType()) 1065 return cast<ArraySubscriptExpr>(this)->getBase()->isLvalue(Ctx); 1066 return LV_Valid; 1067 case DeclRefExprClass: { // C99 6.5.1p2 1068 const NamedDecl *RefdDecl = cast<DeclRefExpr>(this)->getDecl(); 1069 if (DeclCanBeLvalue(RefdDecl, Ctx)) 1070 return LV_Valid; 1071 break; 1072 } 1073 case BlockDeclRefExprClass: { 1074 const BlockDeclRefExpr *BDR = cast<BlockDeclRefExpr>(this); 1075 if (isa<VarDecl>(BDR->getDecl())) 1076 return LV_Valid; 1077 break; 1078 } 1079 case MemberExprClass: { 1080 const MemberExpr *m = cast<MemberExpr>(this); 1081 if (Ctx.getLangOptions().CPlusPlus) { // C++ [expr.ref]p4: 1082 NamedDecl *Member = m->getMemberDecl(); 1083 // C++ [expr.ref]p4: 1084 // If E2 is declared to have type "reference to T", then E1.E2 1085 // is an lvalue. 1086 if (ValueDecl *Value = dyn_cast<ValueDecl>(Member)) 1087 if (Value->getType()->isReferenceType()) 1088 return LV_Valid; 1089 1090 // -- If E2 is a static data member [...] then E1.E2 is an lvalue. 1091 if (isa<VarDecl>(Member) && Member->getDeclContext()->isRecord()) 1092 return LV_Valid; 1093 1094 // -- If E2 is a non-static data member [...]. If E1 is an 1095 // lvalue, then E1.E2 is an lvalue. 1096 if (isa<FieldDecl>(Member)) { 1097 if (m->isArrow()) 1098 return LV_Valid; 1099 return m->getBase()->isLvalue(Ctx); 1100 } 1101 1102 // -- If it refers to a static member function [...], then 1103 // E1.E2 is an lvalue. 1104 // -- Otherwise, if E1.E2 refers to a non-static member 1105 // function [...], then E1.E2 is not an lvalue. 1106 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Member)) 1107 return Method->isStatic()? LV_Valid : LV_MemberFunction; 1108 1109 // -- If E2 is a member enumerator [...], the expression E1.E2 1110 // is not an lvalue. 1111 if (isa<EnumConstantDecl>(Member)) 1112 return LV_InvalidExpression; 1113 1114 // Not an lvalue. 1115 return LV_InvalidExpression; 1116 } 1117 1118 // C99 6.5.2.3p4 1119 if (m->isArrow()) 1120 return LV_Valid; 1121 Expr *BaseExp = m->getBase(); 1122 if (BaseExp->getStmtClass() == ObjCPropertyRefExprClass || 1123 BaseExp->getStmtClass() == ObjCImplicitSetterGetterRefExprClass) 1124 return LV_SubObjCPropertySetting; 1125 return 1126 BaseExp->isLvalue(Ctx); 1127 } 1128 case UnaryOperatorClass: 1129 if (cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::Deref) 1130 return LV_Valid; // C99 6.5.3p4 1131 1132 if (cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::Real || 1133 cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::Imag || 1134 cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::Extension) 1135 return cast<UnaryOperator>(this)->getSubExpr()->isLvalue(Ctx); // GNU. 1136 1137 if (Ctx.getLangOptions().CPlusPlus && // C++ [expr.pre.incr]p1 1138 (cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::PreInc || 1139 cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::PreDec)) 1140 return LV_Valid; 1141 break; 1142 case ImplicitCastExprClass: 1143 if (cast<ImplicitCastExpr>(this)->isLvalueCast()) 1144 return LV_Valid; 1145 1146 // If this is a conversion to a class temporary, make a note of 1147 // that. 1148 if (Ctx.getLangOptions().CPlusPlus && getType()->isRecordType()) 1149 return LV_ClassTemporary; 1150 1151 break; 1152 case ParenExprClass: // C99 6.5.1p5 1153 return cast<ParenExpr>(this)->getSubExpr()->isLvalue(Ctx); 1154 case BinaryOperatorClass: 1155 case CompoundAssignOperatorClass: { 1156 const BinaryOperator *BinOp = cast<BinaryOperator>(this); 1157 1158 if (Ctx.getLangOptions().CPlusPlus && // C++ [expr.comma]p1 1159 BinOp->getOpcode() == BinaryOperator::Comma) 1160 return BinOp->getRHS()->isLvalue(Ctx); 1161 1162 // C++ [expr.mptr.oper]p6 1163 // The result of a .* expression is an lvalue only if its first operand is 1164 // an lvalue and its second operand is a pointer to data member. 1165 if (BinOp->getOpcode() == BinaryOperator::PtrMemD && 1166 !BinOp->getType()->isFunctionType()) 1167 return BinOp->getLHS()->isLvalue(Ctx); 1168 1169 // The result of an ->* expression is an lvalue only if its second operand 1170 // is a pointer to data member. 1171 if (BinOp->getOpcode() == BinaryOperator::PtrMemI && 1172 !BinOp->getType()->isFunctionType()) { 1173 QualType Ty = BinOp->getRHS()->getType(); 1174 if (Ty->isMemberPointerType() && !Ty->isMemberFunctionPointerType()) 1175 return LV_Valid; 1176 } 1177 1178 if (!BinOp->isAssignmentOp()) 1179 return LV_InvalidExpression; 1180 1181 if (Ctx.getLangOptions().CPlusPlus) 1182 // C++ [expr.ass]p1: 1183 // The result of an assignment operation [...] is an lvalue. 1184 return LV_Valid; 1185 1186 1187 // C99 6.5.16: 1188 // An assignment expression [...] is not an lvalue. 1189 return LV_InvalidExpression; 1190 } 1191 case CallExprClass: 1192 case CXXOperatorCallExprClass: 1193 case CXXMemberCallExprClass: { 1194 // C++0x [expr.call]p10 1195 // A function call is an lvalue if and only if the result type 1196 // is an lvalue reference. 1197 QualType ReturnType = cast<CallExpr>(this)->getCallReturnType(); 1198 if (ReturnType->isLValueReferenceType()) 1199 return LV_Valid; 1200 1201 // If the function is returning a class temporary, make a note of 1202 // that. 1203 if (Ctx.getLangOptions().CPlusPlus && ReturnType->isRecordType()) 1204 return LV_ClassTemporary; 1205 1206 break; 1207 } 1208 case CompoundLiteralExprClass: // C99 6.5.2.5p5 1209 // FIXME: Is this what we want in C++? 1210 return LV_Valid; 1211 case ChooseExprClass: 1212 // __builtin_choose_expr is an lvalue if the selected operand is. 1213 return cast<ChooseExpr>(this)->getChosenSubExpr(Ctx)->isLvalue(Ctx); 1214 case ExtVectorElementExprClass: 1215 if (cast<ExtVectorElementExpr>(this)->containsDuplicateElements()) 1216 return LV_DuplicateVectorComponents; 1217 return LV_Valid; 1218 case ObjCIvarRefExprClass: // ObjC instance variables are lvalues. 1219 return LV_Valid; 1220 case ObjCPropertyRefExprClass: // FIXME: check if read-only property. 1221 return LV_Valid; 1222 case ObjCImplicitSetterGetterRefExprClass: // FIXME: check if read-only property. 1223 return LV_Valid; 1224 case PredefinedExprClass: 1225 return LV_Valid; 1226 case UnresolvedLookupExprClass: 1227 return LV_Valid; 1228 case CXXDefaultArgExprClass: 1229 return cast<CXXDefaultArgExpr>(this)->getExpr()->isLvalue(Ctx); 1230 case CStyleCastExprClass: 1231 case CXXFunctionalCastExprClass: 1232 case CXXStaticCastExprClass: 1233 case CXXDynamicCastExprClass: 1234 case CXXReinterpretCastExprClass: 1235 case CXXConstCastExprClass: 1236 // The result of an explicit cast is an lvalue if the type we are 1237 // casting to is an lvalue reference type. See C++ [expr.cast]p1, 1238 // C++ [expr.static.cast]p2, C++ [expr.dynamic.cast]p2, 1239 // C++ [expr.reinterpret.cast]p1, C++ [expr.const.cast]p1. 1240 if (cast<ExplicitCastExpr>(this)->getTypeAsWritten()-> 1241 isLValueReferenceType()) 1242 return LV_Valid; 1243 1244 // If this is a conversion to a class temporary, make a note of 1245 // that. 1246 if (Ctx.getLangOptions().CPlusPlus && 1247 cast<ExplicitCastExpr>(this)->getTypeAsWritten()->isRecordType()) 1248 return LV_ClassTemporary; 1249 1250 break; 1251 case CXXTypeidExprClass: 1252 // C++ 5.2.8p1: The result of a typeid expression is an lvalue of ... 1253 return LV_Valid; 1254 case CXXBindTemporaryExprClass: 1255 return cast<CXXBindTemporaryExpr>(this)->getSubExpr()-> 1256 isLvalueInternal(Ctx); 1257 case CXXBindReferenceExprClass: 1258 // Something that's bound to a reference is always an lvalue. 1259 return LV_Valid; 1260 case ConditionalOperatorClass: { 1261 // Complicated handling is only for C++. 1262 if (!Ctx.getLangOptions().CPlusPlus) 1263 return LV_InvalidExpression; 1264 1265 // Sema should have taken care to ensure that a CXXTemporaryObjectExpr is 1266 // everywhere there's an object converted to an rvalue. Also, any other 1267 // casts should be wrapped by ImplicitCastExprs. There's just the special 1268 // case involving throws to work out. 1269 const ConditionalOperator *Cond = cast<ConditionalOperator>(this); 1270 Expr *True = Cond->getTrueExpr(); 1271 Expr *False = Cond->getFalseExpr(); 1272 // C++0x 5.16p2 1273 // If either the second or the third operand has type (cv) void, [...] 1274 // the result [...] is an rvalue. 1275 if (True->getType()->isVoidType() || False->getType()->isVoidType()) 1276 return LV_InvalidExpression; 1277 1278 // Both sides must be lvalues for the result to be an lvalue. 1279 if (True->isLvalue(Ctx) != LV_Valid || False->isLvalue(Ctx) != LV_Valid) 1280 return LV_InvalidExpression; 1281 1282 // That's it. 1283 return LV_Valid; 1284 } 1285 1286 case Expr::CXXExprWithTemporariesClass: 1287 return cast<CXXExprWithTemporaries>(this)->getSubExpr()->isLvalue(Ctx); 1288 1289 case Expr::ObjCMessageExprClass: 1290 if (const ObjCMethodDecl *Method 1291 = cast<ObjCMessageExpr>(this)->getMethodDecl()) 1292 if (Method->getResultType()->isLValueReferenceType()) 1293 return LV_Valid; 1294 break; 1295 1296 case Expr::CXXConstructExprClass: 1297 case Expr::CXXTemporaryObjectExprClass: 1298 case Expr::CXXZeroInitValueExprClass: 1299 return LV_ClassTemporary; 1300 1301 default: 1302 break; 1303 } 1304 return LV_InvalidExpression; 1305} 1306 1307/// isModifiableLvalue - C99 6.3.2.1: an lvalue that does not have array type, 1308/// does not have an incomplete type, does not have a const-qualified type, and 1309/// if it is a structure or union, does not have any member (including, 1310/// recursively, any member or element of all contained aggregates or unions) 1311/// with a const-qualified type. 1312Expr::isModifiableLvalueResult 1313Expr::isModifiableLvalue(ASTContext &Ctx, SourceLocation *Loc) const { 1314 isLvalueResult lvalResult = isLvalue(Ctx); 1315 1316 switch (lvalResult) { 1317 case LV_Valid: 1318 // C++ 3.10p11: Functions cannot be modified, but pointers to 1319 // functions can be modifiable. 1320 if (Ctx.getLangOptions().CPlusPlus && TR->isFunctionType()) 1321 return MLV_NotObjectType; 1322 break; 1323 1324 case LV_NotObjectType: return MLV_NotObjectType; 1325 case LV_IncompleteVoidType: return MLV_IncompleteVoidType; 1326 case LV_DuplicateVectorComponents: return MLV_DuplicateVectorComponents; 1327 case LV_InvalidExpression: 1328 // If the top level is a C-style cast, and the subexpression is a valid 1329 // lvalue, then this is probably a use of the old-school "cast as lvalue" 1330 // GCC extension. We don't support it, but we want to produce good 1331 // diagnostics when it happens so that the user knows why. 1332 if (const CStyleCastExpr *CE = dyn_cast<CStyleCastExpr>(IgnoreParens())) { 1333 if (CE->getSubExpr()->isLvalue(Ctx) == LV_Valid) { 1334 if (Loc) 1335 *Loc = CE->getLParenLoc(); 1336 return MLV_LValueCast; 1337 } 1338 } 1339 return MLV_InvalidExpression; 1340 case LV_MemberFunction: return MLV_MemberFunction; 1341 case LV_SubObjCPropertySetting: return MLV_SubObjCPropertySetting; 1342 case LV_ClassTemporary: 1343 return MLV_ClassTemporary; 1344 } 1345 1346 // The following is illegal: 1347 // void takeclosure(void (^C)(void)); 1348 // void func() { int x = 1; takeclosure(^{ x = 7; }); } 1349 // 1350 if (const BlockDeclRefExpr *BDR = dyn_cast<BlockDeclRefExpr>(this)) { 1351 if (!BDR->isByRef() && isa<VarDecl>(BDR->getDecl())) 1352 return MLV_NotBlockQualified; 1353 } 1354 1355 // Assigning to an 'implicit' property? 1356 if (const ObjCImplicitSetterGetterRefExpr* Expr = 1357 dyn_cast<ObjCImplicitSetterGetterRefExpr>(this)) { 1358 if (Expr->getSetterMethod() == 0) 1359 return MLV_NoSetterProperty; 1360 } 1361 1362 QualType CT = Ctx.getCanonicalType(getType()); 1363 1364 if (CT.isConstQualified()) 1365 return MLV_ConstQualified; 1366 if (CT->isArrayType()) 1367 return MLV_ArrayType; 1368 if (CT->isIncompleteType()) 1369 return MLV_IncompleteType; 1370 1371 if (const RecordType *r = CT->getAs<RecordType>()) { 1372 if (r->hasConstFields()) 1373 return MLV_ConstQualified; 1374 } 1375 1376 return MLV_Valid; 1377} 1378 1379/// isOBJCGCCandidate - Check if an expression is objc gc'able. 1380/// returns true, if it is; false otherwise. 1381bool Expr::isOBJCGCCandidate(ASTContext &Ctx) const { 1382 switch (getStmtClass()) { 1383 default: 1384 return false; 1385 case ObjCIvarRefExprClass: 1386 return true; 1387 case Expr::UnaryOperatorClass: 1388 return cast<UnaryOperator>(this)->getSubExpr()->isOBJCGCCandidate(Ctx); 1389 case ParenExprClass: 1390 return cast<ParenExpr>(this)->getSubExpr()->isOBJCGCCandidate(Ctx); 1391 case ImplicitCastExprClass: 1392 return cast<ImplicitCastExpr>(this)->getSubExpr()->isOBJCGCCandidate(Ctx); 1393 case CStyleCastExprClass: 1394 return cast<CStyleCastExpr>(this)->getSubExpr()->isOBJCGCCandidate(Ctx); 1395 case DeclRefExprClass: { 1396 const Decl *D = cast<DeclRefExpr>(this)->getDecl(); 1397 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1398 if (VD->hasGlobalStorage()) 1399 return true; 1400 QualType T = VD->getType(); 1401 // dereferencing to a pointer is always a gc'able candidate, 1402 // unless it is __weak. 1403 return T->isPointerType() && 1404 (Ctx.getObjCGCAttrKind(T) != Qualifiers::Weak); 1405 } 1406 return false; 1407 } 1408 case MemberExprClass: { 1409 const MemberExpr *M = cast<MemberExpr>(this); 1410 return M->getBase()->isOBJCGCCandidate(Ctx); 1411 } 1412 case ArraySubscriptExprClass: 1413 return cast<ArraySubscriptExpr>(this)->getBase()->isOBJCGCCandidate(Ctx); 1414 } 1415} 1416Expr* Expr::IgnoreParens() { 1417 Expr* E = this; 1418 while (ParenExpr* P = dyn_cast<ParenExpr>(E)) 1419 E = P->getSubExpr(); 1420 1421 return E; 1422} 1423 1424/// IgnoreParenCasts - Ignore parentheses and casts. Strip off any ParenExpr 1425/// or CastExprs or ImplicitCastExprs, returning their operand. 1426Expr *Expr::IgnoreParenCasts() { 1427 Expr *E = this; 1428 while (true) { 1429 if (ParenExpr *P = dyn_cast<ParenExpr>(E)) 1430 E = P->getSubExpr(); 1431 else if (CastExpr *P = dyn_cast<CastExpr>(E)) 1432 E = P->getSubExpr(); 1433 else 1434 return E; 1435 } 1436} 1437 1438/// IgnoreParenNoopCasts - Ignore parentheses and casts that do not change the 1439/// value (including ptr->int casts of the same size). Strip off any 1440/// ParenExpr or CastExprs, returning their operand. 1441Expr *Expr::IgnoreParenNoopCasts(ASTContext &Ctx) { 1442 Expr *E = this; 1443 while (true) { 1444 if (ParenExpr *P = dyn_cast<ParenExpr>(E)) { 1445 E = P->getSubExpr(); 1446 continue; 1447 } 1448 1449 if (CastExpr *P = dyn_cast<CastExpr>(E)) { 1450 // We ignore integer <-> casts that are of the same width, ptr<->ptr and 1451 // ptr<->int casts of the same width. We also ignore all identify casts. 1452 Expr *SE = P->getSubExpr(); 1453 1454 if (Ctx.hasSameUnqualifiedType(E->getType(), SE->getType())) { 1455 E = SE; 1456 continue; 1457 } 1458 1459 if ((E->getType()->isPointerType() || E->getType()->isIntegralType()) && 1460 (SE->getType()->isPointerType() || SE->getType()->isIntegralType()) && 1461 Ctx.getTypeSize(E->getType()) == Ctx.getTypeSize(SE->getType())) { 1462 E = SE; 1463 continue; 1464 } 1465 } 1466 1467 return E; 1468 } 1469} 1470 1471bool Expr::isDefaultArgument() const { 1472 const Expr *E = this; 1473 while (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) 1474 E = ICE->getSubExprAsWritten(); 1475 1476 return isa<CXXDefaultArgExpr>(E); 1477} 1478 1479/// hasAnyTypeDependentArguments - Determines if any of the expressions 1480/// in Exprs is type-dependent. 1481bool Expr::hasAnyTypeDependentArguments(Expr** Exprs, unsigned NumExprs) { 1482 for (unsigned I = 0; I < NumExprs; ++I) 1483 if (Exprs[I]->isTypeDependent()) 1484 return true; 1485 1486 return false; 1487} 1488 1489/// hasAnyValueDependentArguments - Determines if any of the expressions 1490/// in Exprs is value-dependent. 1491bool Expr::hasAnyValueDependentArguments(Expr** Exprs, unsigned NumExprs) { 1492 for (unsigned I = 0; I < NumExprs; ++I) 1493 if (Exprs[I]->isValueDependent()) 1494 return true; 1495 1496 return false; 1497} 1498 1499bool Expr::isConstantInitializer(ASTContext &Ctx) const { 1500 // This function is attempting whether an expression is an initializer 1501 // which can be evaluated at compile-time. isEvaluatable handles most 1502 // of the cases, but it can't deal with some initializer-specific 1503 // expressions, and it can't deal with aggregates; we deal with those here, 1504 // and fall back to isEvaluatable for the other cases. 1505 1506 // FIXME: This function assumes the variable being assigned to 1507 // isn't a reference type! 1508 1509 switch (getStmtClass()) { 1510 default: break; 1511 case StringLiteralClass: 1512 case ObjCStringLiteralClass: 1513 case ObjCEncodeExprClass: 1514 return true; 1515 case CompoundLiteralExprClass: { 1516 // This handles gcc's extension that allows global initializers like 1517 // "struct x {int x;} x = (struct x) {};". 1518 // FIXME: This accepts other cases it shouldn't! 1519 const Expr *Exp = cast<CompoundLiteralExpr>(this)->getInitializer(); 1520 return Exp->isConstantInitializer(Ctx); 1521 } 1522 case InitListExprClass: { 1523 // FIXME: This doesn't deal with fields with reference types correctly. 1524 // FIXME: This incorrectly allows pointers cast to integers to be assigned 1525 // to bitfields. 1526 const InitListExpr *Exp = cast<InitListExpr>(this); 1527 unsigned numInits = Exp->getNumInits(); 1528 for (unsigned i = 0; i < numInits; i++) { 1529 if (!Exp->getInit(i)->isConstantInitializer(Ctx)) 1530 return false; 1531 } 1532 return true; 1533 } 1534 case ImplicitValueInitExprClass: 1535 return true; 1536 case ParenExprClass: 1537 return cast<ParenExpr>(this)->getSubExpr()->isConstantInitializer(Ctx); 1538 case UnaryOperatorClass: { 1539 const UnaryOperator* Exp = cast<UnaryOperator>(this); 1540 if (Exp->getOpcode() == UnaryOperator::Extension) 1541 return Exp->getSubExpr()->isConstantInitializer(Ctx); 1542 break; 1543 } 1544 case BinaryOperatorClass: { 1545 // Special case &&foo - &&bar. It would be nice to generalize this somehow 1546 // but this handles the common case. 1547 const BinaryOperator *Exp = cast<BinaryOperator>(this); 1548 if (Exp->getOpcode() == BinaryOperator::Sub && 1549 isa<AddrLabelExpr>(Exp->getLHS()->IgnoreParenNoopCasts(Ctx)) && 1550 isa<AddrLabelExpr>(Exp->getRHS()->IgnoreParenNoopCasts(Ctx))) 1551 return true; 1552 break; 1553 } 1554 case ImplicitCastExprClass: 1555 case CStyleCastExprClass: 1556 // Handle casts with a destination that's a struct or union; this 1557 // deals with both the gcc no-op struct cast extension and the 1558 // cast-to-union extension. 1559 if (getType()->isRecordType()) 1560 return cast<CastExpr>(this)->getSubExpr()->isConstantInitializer(Ctx); 1561 1562 // Integer->integer casts can be handled here, which is important for 1563 // things like (int)(&&x-&&y). Scary but true. 1564 if (getType()->isIntegerType() && 1565 cast<CastExpr>(this)->getSubExpr()->getType()->isIntegerType()) 1566 return cast<CastExpr>(this)->getSubExpr()->isConstantInitializer(Ctx); 1567 1568 break; 1569 } 1570 return isEvaluatable(Ctx); 1571} 1572 1573/// isIntegerConstantExpr - this recursive routine will test if an expression is 1574/// an integer constant expression. 1575 1576/// FIXME: Pass up a reason why! Invalid operation in i-c-e, division by zero, 1577/// comma, etc 1578/// 1579/// FIXME: Handle offsetof. Two things to do: Handle GCC's __builtin_offsetof 1580/// to support gcc 4.0+ and handle the idiom GCC recognizes with a null pointer 1581/// cast+dereference. 1582 1583// CheckICE - This function does the fundamental ICE checking: the returned 1584// ICEDiag contains a Val of 0, 1, or 2, and a possibly null SourceLocation. 1585// Note that to reduce code duplication, this helper does no evaluation 1586// itself; the caller checks whether the expression is evaluatable, and 1587// in the rare cases where CheckICE actually cares about the evaluated 1588// value, it calls into Evalute. 1589// 1590// Meanings of Val: 1591// 0: This expression is an ICE if it can be evaluated by Evaluate. 1592// 1: This expression is not an ICE, but if it isn't evaluated, it's 1593// a legal subexpression for an ICE. This return value is used to handle 1594// the comma operator in C99 mode. 1595// 2: This expression is not an ICE, and is not a legal subexpression for one. 1596 1597struct ICEDiag { 1598 unsigned Val; 1599 SourceLocation Loc; 1600 1601 public: 1602 ICEDiag(unsigned v, SourceLocation l) : Val(v), Loc(l) {} 1603 ICEDiag() : Val(0) {} 1604}; 1605 1606ICEDiag NoDiag() { return ICEDiag(); } 1607 1608static ICEDiag CheckEvalInICE(const Expr* E, ASTContext &Ctx) { 1609 Expr::EvalResult EVResult; 1610 if (!E->Evaluate(EVResult, Ctx) || EVResult.HasSideEffects || 1611 !EVResult.Val.isInt()) { 1612 return ICEDiag(2, E->getLocStart()); 1613 } 1614 return NoDiag(); 1615} 1616 1617static ICEDiag CheckICE(const Expr* E, ASTContext &Ctx) { 1618 assert(!E->isValueDependent() && "Should not see value dependent exprs!"); 1619 if (!E->getType()->isIntegralType()) { 1620 return ICEDiag(2, E->getLocStart()); 1621 } 1622 1623 switch (E->getStmtClass()) { 1624#define STMT(Node, Base) case Expr::Node##Class: 1625#define EXPR(Node, Base) 1626#include "clang/AST/StmtNodes.def" 1627 case Expr::PredefinedExprClass: 1628 case Expr::FloatingLiteralClass: 1629 case Expr::ImaginaryLiteralClass: 1630 case Expr::StringLiteralClass: 1631 case Expr::ArraySubscriptExprClass: 1632 case Expr::MemberExprClass: 1633 case Expr::CompoundAssignOperatorClass: 1634 case Expr::CompoundLiteralExprClass: 1635 case Expr::ExtVectorElementExprClass: 1636 case Expr::InitListExprClass: 1637 case Expr::DesignatedInitExprClass: 1638 case Expr::ImplicitValueInitExprClass: 1639 case Expr::ParenListExprClass: 1640 case Expr::VAArgExprClass: 1641 case Expr::AddrLabelExprClass: 1642 case Expr::StmtExprClass: 1643 case Expr::CXXMemberCallExprClass: 1644 case Expr::CXXDynamicCastExprClass: 1645 case Expr::CXXTypeidExprClass: 1646 case Expr::CXXNullPtrLiteralExprClass: 1647 case Expr::CXXThisExprClass: 1648 case Expr::CXXThrowExprClass: 1649 case Expr::CXXNewExprClass: 1650 case Expr::CXXDeleteExprClass: 1651 case Expr::CXXPseudoDestructorExprClass: 1652 case Expr::UnresolvedLookupExprClass: 1653 case Expr::DependentScopeDeclRefExprClass: 1654 case Expr::CXXConstructExprClass: 1655 case Expr::CXXBindTemporaryExprClass: 1656 case Expr::CXXBindReferenceExprClass: 1657 case Expr::CXXExprWithTemporariesClass: 1658 case Expr::CXXTemporaryObjectExprClass: 1659 case Expr::CXXUnresolvedConstructExprClass: 1660 case Expr::CXXDependentScopeMemberExprClass: 1661 case Expr::UnresolvedMemberExprClass: 1662 case Expr::ObjCStringLiteralClass: 1663 case Expr::ObjCEncodeExprClass: 1664 case Expr::ObjCMessageExprClass: 1665 case Expr::ObjCSelectorExprClass: 1666 case Expr::ObjCProtocolExprClass: 1667 case Expr::ObjCIvarRefExprClass: 1668 case Expr::ObjCPropertyRefExprClass: 1669 case Expr::ObjCImplicitSetterGetterRefExprClass: 1670 case Expr::ObjCSuperExprClass: 1671 case Expr::ObjCIsaExprClass: 1672 case Expr::ShuffleVectorExprClass: 1673 case Expr::BlockExprClass: 1674 case Expr::BlockDeclRefExprClass: 1675 case Expr::NoStmtClass: 1676 return ICEDiag(2, E->getLocStart()); 1677 1678 case Expr::GNUNullExprClass: 1679 // GCC considers the GNU __null value to be an integral constant expression. 1680 return NoDiag(); 1681 1682 case Expr::ParenExprClass: 1683 return CheckICE(cast<ParenExpr>(E)->getSubExpr(), Ctx); 1684 case Expr::IntegerLiteralClass: 1685 case Expr::CharacterLiteralClass: 1686 case Expr::CXXBoolLiteralExprClass: 1687 case Expr::CXXZeroInitValueExprClass: 1688 case Expr::TypesCompatibleExprClass: 1689 case Expr::UnaryTypeTraitExprClass: 1690 return NoDiag(); 1691 case Expr::CallExprClass: 1692 case Expr::CXXOperatorCallExprClass: { 1693 const CallExpr *CE = cast<CallExpr>(E); 1694 if (CE->isBuiltinCall(Ctx)) 1695 return CheckEvalInICE(E, Ctx); 1696 return ICEDiag(2, E->getLocStart()); 1697 } 1698 case Expr::DeclRefExprClass: 1699 if (isa<EnumConstantDecl>(cast<DeclRefExpr>(E)->getDecl())) 1700 return NoDiag(); 1701 if (Ctx.getLangOptions().CPlusPlus && 1702 E->getType().getCVRQualifiers() == Qualifiers::Const) { 1703 const NamedDecl *D = cast<DeclRefExpr>(E)->getDecl(); 1704 1705 // Parameter variables are never constants. Without this check, 1706 // getAnyInitializer() can find a default argument, which leads 1707 // to chaos. 1708 if (isa<ParmVarDecl>(D)) 1709 return ICEDiag(2, cast<DeclRefExpr>(E)->getLocation()); 1710 1711 // C++ 7.1.5.1p2 1712 // A variable of non-volatile const-qualified integral or enumeration 1713 // type initialized by an ICE can be used in ICEs. 1714 if (const VarDecl *Dcl = dyn_cast<VarDecl>(D)) { 1715 Qualifiers Quals = Ctx.getCanonicalType(Dcl->getType()).getQualifiers(); 1716 if (Quals.hasVolatile() || !Quals.hasConst()) 1717 return ICEDiag(2, cast<DeclRefExpr>(E)->getLocation()); 1718 1719 // Look for a declaration of this variable that has an initializer. 1720 const VarDecl *ID = 0; 1721 const Expr *Init = Dcl->getAnyInitializer(ID); 1722 if (Init) { 1723 if (ID->isInitKnownICE()) { 1724 // We have already checked whether this subexpression is an 1725 // integral constant expression. 1726 if (ID->isInitICE()) 1727 return NoDiag(); 1728 else 1729 return ICEDiag(2, cast<DeclRefExpr>(E)->getLocation()); 1730 } 1731 1732 // It's an ICE whether or not the definition we found is 1733 // out-of-line. See DR 721 and the discussion in Clang PR 1734 // 6206 for details. 1735 1736 if (Dcl->isCheckingICE()) { 1737 return ICEDiag(2, cast<DeclRefExpr>(E)->getLocation()); 1738 } 1739 1740 Dcl->setCheckingICE(); 1741 ICEDiag Result = CheckICE(Init, Ctx); 1742 // Cache the result of the ICE test. 1743 Dcl->setInitKnownICE(Result.Val == 0); 1744 return Result; 1745 } 1746 } 1747 } 1748 return ICEDiag(2, E->getLocStart()); 1749 case Expr::UnaryOperatorClass: { 1750 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1751 switch (Exp->getOpcode()) { 1752 case UnaryOperator::PostInc: 1753 case UnaryOperator::PostDec: 1754 case UnaryOperator::PreInc: 1755 case UnaryOperator::PreDec: 1756 case UnaryOperator::AddrOf: 1757 case UnaryOperator::Deref: 1758 return ICEDiag(2, E->getLocStart()); 1759 1760 case UnaryOperator::Extension: 1761 case UnaryOperator::LNot: 1762 case UnaryOperator::Plus: 1763 case UnaryOperator::Minus: 1764 case UnaryOperator::Not: 1765 case UnaryOperator::Real: 1766 case UnaryOperator::Imag: 1767 return CheckICE(Exp->getSubExpr(), Ctx); 1768 case UnaryOperator::OffsetOf: 1769 // Note that per C99, offsetof must be an ICE. And AFAIK, using 1770 // Evaluate matches the proposed gcc behavior for cases like 1771 // "offsetof(struct s{int x[4];}, x[!.0])". This doesn't affect 1772 // compliance: we should warn earlier for offsetof expressions with 1773 // array subscripts that aren't ICEs, and if the array subscripts 1774 // are ICEs, the value of the offsetof must be an integer constant. 1775 return CheckEvalInICE(E, Ctx); 1776 } 1777 } 1778 case Expr::SizeOfAlignOfExprClass: { 1779 const SizeOfAlignOfExpr *Exp = cast<SizeOfAlignOfExpr>(E); 1780 if (Exp->isSizeOf() && Exp->getTypeOfArgument()->isVariableArrayType()) 1781 return ICEDiag(2, E->getLocStart()); 1782 return NoDiag(); 1783 } 1784 case Expr::BinaryOperatorClass: { 1785 const BinaryOperator *Exp = cast<BinaryOperator>(E); 1786 switch (Exp->getOpcode()) { 1787 case BinaryOperator::PtrMemD: 1788 case BinaryOperator::PtrMemI: 1789 case BinaryOperator::Assign: 1790 case BinaryOperator::MulAssign: 1791 case BinaryOperator::DivAssign: 1792 case BinaryOperator::RemAssign: 1793 case BinaryOperator::AddAssign: 1794 case BinaryOperator::SubAssign: 1795 case BinaryOperator::ShlAssign: 1796 case BinaryOperator::ShrAssign: 1797 case BinaryOperator::AndAssign: 1798 case BinaryOperator::XorAssign: 1799 case BinaryOperator::OrAssign: 1800 return ICEDiag(2, E->getLocStart()); 1801 1802 case BinaryOperator::Mul: 1803 case BinaryOperator::Div: 1804 case BinaryOperator::Rem: 1805 case BinaryOperator::Add: 1806 case BinaryOperator::Sub: 1807 case BinaryOperator::Shl: 1808 case BinaryOperator::Shr: 1809 case BinaryOperator::LT: 1810 case BinaryOperator::GT: 1811 case BinaryOperator::LE: 1812 case BinaryOperator::GE: 1813 case BinaryOperator::EQ: 1814 case BinaryOperator::NE: 1815 case BinaryOperator::And: 1816 case BinaryOperator::Xor: 1817 case BinaryOperator::Or: 1818 case BinaryOperator::Comma: { 1819 ICEDiag LHSResult = CheckICE(Exp->getLHS(), Ctx); 1820 ICEDiag RHSResult = CheckICE(Exp->getRHS(), Ctx); 1821 if (Exp->getOpcode() == BinaryOperator::Div || 1822 Exp->getOpcode() == BinaryOperator::Rem) { 1823 // Evaluate gives an error for undefined Div/Rem, so make sure 1824 // we don't evaluate one. 1825 if (LHSResult.Val != 2 && RHSResult.Val != 2) { 1826 llvm::APSInt REval = Exp->getRHS()->EvaluateAsInt(Ctx); 1827 if (REval == 0) 1828 return ICEDiag(1, E->getLocStart()); 1829 if (REval.isSigned() && REval.isAllOnesValue()) { 1830 llvm::APSInt LEval = Exp->getLHS()->EvaluateAsInt(Ctx); 1831 if (LEval.isMinSignedValue()) 1832 return ICEDiag(1, E->getLocStart()); 1833 } 1834 } 1835 } 1836 if (Exp->getOpcode() == BinaryOperator::Comma) { 1837 if (Ctx.getLangOptions().C99) { 1838 // C99 6.6p3 introduces a strange edge case: comma can be in an ICE 1839 // if it isn't evaluated. 1840 if (LHSResult.Val == 0 && RHSResult.Val == 0) 1841 return ICEDiag(1, E->getLocStart()); 1842 } else { 1843 // In both C89 and C++, commas in ICEs are illegal. 1844 return ICEDiag(2, E->getLocStart()); 1845 } 1846 } 1847 if (LHSResult.Val >= RHSResult.Val) 1848 return LHSResult; 1849 return RHSResult; 1850 } 1851 case BinaryOperator::LAnd: 1852 case BinaryOperator::LOr: { 1853 ICEDiag LHSResult = CheckICE(Exp->getLHS(), Ctx); 1854 ICEDiag RHSResult = CheckICE(Exp->getRHS(), Ctx); 1855 if (LHSResult.Val == 0 && RHSResult.Val == 1) { 1856 // Rare case where the RHS has a comma "side-effect"; we need 1857 // to actually check the condition to see whether the side 1858 // with the comma is evaluated. 1859 if ((Exp->getOpcode() == BinaryOperator::LAnd) != 1860 (Exp->getLHS()->EvaluateAsInt(Ctx) == 0)) 1861 return RHSResult; 1862 return NoDiag(); 1863 } 1864 1865 if (LHSResult.Val >= RHSResult.Val) 1866 return LHSResult; 1867 return RHSResult; 1868 } 1869 } 1870 } 1871 case Expr::ImplicitCastExprClass: 1872 case Expr::CStyleCastExprClass: 1873 case Expr::CXXFunctionalCastExprClass: 1874 case Expr::CXXNamedCastExprClass: 1875 case Expr::CXXStaticCastExprClass: 1876 case Expr::CXXReinterpretCastExprClass: 1877 case Expr::CXXConstCastExprClass: { 1878 const Expr *SubExpr = cast<CastExpr>(E)->getSubExpr(); 1879 if (SubExpr->getType()->isIntegralType()) 1880 return CheckICE(SubExpr, Ctx); 1881 if (isa<FloatingLiteral>(SubExpr->IgnoreParens())) 1882 return NoDiag(); 1883 return ICEDiag(2, E->getLocStart()); 1884 } 1885 case Expr::ConditionalOperatorClass: { 1886 const ConditionalOperator *Exp = cast<ConditionalOperator>(E); 1887 // If the condition (ignoring parens) is a __builtin_constant_p call, 1888 // then only the true side is actually considered in an integer constant 1889 // expression, and it is fully evaluated. This is an important GNU 1890 // extension. See GCC PR38377 for discussion. 1891 if (const CallExpr *CallCE = dyn_cast<CallExpr>(Exp->getCond()->IgnoreParenCasts())) 1892 if (CallCE->isBuiltinCall(Ctx) == Builtin::BI__builtin_constant_p) { 1893 Expr::EvalResult EVResult; 1894 if (!E->Evaluate(EVResult, Ctx) || EVResult.HasSideEffects || 1895 !EVResult.Val.isInt()) { 1896 return ICEDiag(2, E->getLocStart()); 1897 } 1898 return NoDiag(); 1899 } 1900 ICEDiag CondResult = CheckICE(Exp->getCond(), Ctx); 1901 ICEDiag TrueResult = CheckICE(Exp->getTrueExpr(), Ctx); 1902 ICEDiag FalseResult = CheckICE(Exp->getFalseExpr(), Ctx); 1903 if (CondResult.Val == 2) 1904 return CondResult; 1905 if (TrueResult.Val == 2) 1906 return TrueResult; 1907 if (FalseResult.Val == 2) 1908 return FalseResult; 1909 if (CondResult.Val == 1) 1910 return CondResult; 1911 if (TrueResult.Val == 0 && FalseResult.Val == 0) 1912 return NoDiag(); 1913 // Rare case where the diagnostics depend on which side is evaluated 1914 // Note that if we get here, CondResult is 0, and at least one of 1915 // TrueResult and FalseResult is non-zero. 1916 if (Exp->getCond()->EvaluateAsInt(Ctx) == 0) { 1917 return FalseResult; 1918 } 1919 return TrueResult; 1920 } 1921 case Expr::CXXDefaultArgExprClass: 1922 return CheckICE(cast<CXXDefaultArgExpr>(E)->getExpr(), Ctx); 1923 case Expr::ChooseExprClass: { 1924 return CheckICE(cast<ChooseExpr>(E)->getChosenSubExpr(Ctx), Ctx); 1925 } 1926 } 1927 1928 // Silence a GCC warning 1929 return ICEDiag(2, E->getLocStart()); 1930} 1931 1932bool Expr::isIntegerConstantExpr(llvm::APSInt &Result, ASTContext &Ctx, 1933 SourceLocation *Loc, bool isEvaluated) const { 1934 ICEDiag d = CheckICE(this, Ctx); 1935 if (d.Val != 0) { 1936 if (Loc) *Loc = d.Loc; 1937 return false; 1938 } 1939 EvalResult EvalResult; 1940 if (!Evaluate(EvalResult, Ctx)) 1941 llvm_unreachable("ICE cannot be evaluated!"); 1942 assert(!EvalResult.HasSideEffects && "ICE with side effects!"); 1943 assert(EvalResult.Val.isInt() && "ICE that isn't integer!"); 1944 Result = EvalResult.Val.getInt(); 1945 return true; 1946} 1947 1948/// isNullPointerConstant - C99 6.3.2.3p3 - Return true if this is either an 1949/// integer constant expression with the value zero, or if this is one that is 1950/// cast to void*. 1951bool Expr::isNullPointerConstant(ASTContext &Ctx, 1952 NullPointerConstantValueDependence NPC) const { 1953 if (isValueDependent()) { 1954 switch (NPC) { 1955 case NPC_NeverValueDependent: 1956 assert(false && "Unexpected value dependent expression!"); 1957 // If the unthinkable happens, fall through to the safest alternative. 1958 1959 case NPC_ValueDependentIsNull: 1960 return isTypeDependent() || getType()->isIntegralType(); 1961 1962 case NPC_ValueDependentIsNotNull: 1963 return false; 1964 } 1965 } 1966 1967 // Strip off a cast to void*, if it exists. Except in C++. 1968 if (const ExplicitCastExpr *CE = dyn_cast<ExplicitCastExpr>(this)) { 1969 if (!Ctx.getLangOptions().CPlusPlus) { 1970 // Check that it is a cast to void*. 1971 if (const PointerType *PT = CE->getType()->getAs<PointerType>()) { 1972 QualType Pointee = PT->getPointeeType(); 1973 if (!Pointee.hasQualifiers() && 1974 Pointee->isVoidType() && // to void* 1975 CE->getSubExpr()->getType()->isIntegerType()) // from int. 1976 return CE->getSubExpr()->isNullPointerConstant(Ctx, NPC); 1977 } 1978 } 1979 } else if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(this)) { 1980 // Ignore the ImplicitCastExpr type entirely. 1981 return ICE->getSubExpr()->isNullPointerConstant(Ctx, NPC); 1982 } else if (const ParenExpr *PE = dyn_cast<ParenExpr>(this)) { 1983 // Accept ((void*)0) as a null pointer constant, as many other 1984 // implementations do. 1985 return PE->getSubExpr()->isNullPointerConstant(Ctx, NPC); 1986 } else if (const CXXDefaultArgExpr *DefaultArg 1987 = dyn_cast<CXXDefaultArgExpr>(this)) { 1988 // See through default argument expressions 1989 return DefaultArg->getExpr()->isNullPointerConstant(Ctx, NPC); 1990 } else if (isa<GNUNullExpr>(this)) { 1991 // The GNU __null extension is always a null pointer constant. 1992 return true; 1993 } 1994 1995 // C++0x nullptr_t is always a null pointer constant. 1996 if (getType()->isNullPtrType()) 1997 return true; 1998 1999 // This expression must be an integer type. 2000 if (!getType()->isIntegerType() || 2001 (Ctx.getLangOptions().CPlusPlus && getType()->isEnumeralType())) 2002 return false; 2003 2004 // If we have an integer constant expression, we need to *evaluate* it and 2005 // test for the value 0. 2006 llvm::APSInt Result; 2007 return isIntegerConstantExpr(Result, Ctx) && Result == 0; 2008} 2009 2010FieldDecl *Expr::getBitField() { 2011 Expr *E = this->IgnoreParens(); 2012 2013 while (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) { 2014 if (ICE->isLvalueCast() && ICE->getCastKind() == CastExpr::CK_NoOp) 2015 E = ICE->getSubExpr()->IgnoreParens(); 2016 else 2017 break; 2018 } 2019 2020 if (MemberExpr *MemRef = dyn_cast<MemberExpr>(E)) 2021 if (FieldDecl *Field = dyn_cast<FieldDecl>(MemRef->getMemberDecl())) 2022 if (Field->isBitField()) 2023 return Field; 2024 2025 if (BinaryOperator *BinOp = dyn_cast<BinaryOperator>(E)) 2026 if (BinOp->isAssignmentOp() && BinOp->getLHS()) 2027 return BinOp->getLHS()->getBitField(); 2028 2029 return 0; 2030} 2031 2032bool Expr::refersToVectorElement() const { 2033 const Expr *E = this->IgnoreParens(); 2034 2035 while (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) { 2036 if (ICE->isLvalueCast() && ICE->getCastKind() == CastExpr::CK_NoOp) 2037 E = ICE->getSubExpr()->IgnoreParens(); 2038 else 2039 break; 2040 } 2041 2042 if (const ArraySubscriptExpr *ASE = dyn_cast<ArraySubscriptExpr>(E)) 2043 return ASE->getBase()->getType()->isVectorType(); 2044 2045 if (isa<ExtVectorElementExpr>(E)) 2046 return true; 2047 2048 return false; 2049} 2050 2051/// isArrow - Return true if the base expression is a pointer to vector, 2052/// return false if the base expression is a vector. 2053bool ExtVectorElementExpr::isArrow() const { 2054 return getBase()->getType()->isPointerType(); 2055} 2056 2057unsigned ExtVectorElementExpr::getNumElements() const { 2058 if (const VectorType *VT = getType()->getAs<VectorType>()) 2059 return VT->getNumElements(); 2060 return 1; 2061} 2062 2063/// containsDuplicateElements - Return true if any element access is repeated. 2064bool ExtVectorElementExpr::containsDuplicateElements() const { 2065 // FIXME: Refactor this code to an accessor on the AST node which returns the 2066 // "type" of component access, and share with code below and in Sema. 2067 llvm::StringRef Comp = Accessor->getName(); 2068 2069 // Halving swizzles do not contain duplicate elements. 2070 if (Comp == "hi" || Comp == "lo" || Comp == "even" || Comp == "odd") 2071 return false; 2072 2073 // Advance past s-char prefix on hex swizzles. 2074 if (Comp[0] == 's' || Comp[0] == 'S') 2075 Comp = Comp.substr(1); 2076 2077 for (unsigned i = 0, e = Comp.size(); i != e; ++i) 2078 if (Comp.substr(i + 1).find(Comp[i]) != llvm::StringRef::npos) 2079 return true; 2080 2081 return false; 2082} 2083 2084/// getEncodedElementAccess - We encode the fields as a llvm ConstantArray. 2085void ExtVectorElementExpr::getEncodedElementAccess( 2086 llvm::SmallVectorImpl<unsigned> &Elts) const { 2087 llvm::StringRef Comp = Accessor->getName(); 2088 if (Comp[0] == 's' || Comp[0] == 'S') 2089 Comp = Comp.substr(1); 2090 2091 bool isHi = Comp == "hi"; 2092 bool isLo = Comp == "lo"; 2093 bool isEven = Comp == "even"; 2094 bool isOdd = Comp == "odd"; 2095 2096 for (unsigned i = 0, e = getNumElements(); i != e; ++i) { 2097 uint64_t Index; 2098 2099 if (isHi) 2100 Index = e + i; 2101 else if (isLo) 2102 Index = i; 2103 else if (isEven) 2104 Index = 2 * i; 2105 else if (isOdd) 2106 Index = 2 * i + 1; 2107 else 2108 Index = ExtVectorType::getAccessorIdx(Comp[i]); 2109 2110 Elts.push_back(Index); 2111 } 2112} 2113 2114// constructor for instance messages. 2115ObjCMessageExpr::ObjCMessageExpr(ASTContext &C, Expr *receiver, 2116 Selector selInfo, 2117 QualType retType, ObjCMethodDecl *mproto, 2118 SourceLocation LBrac, SourceLocation RBrac, 2119 Expr **ArgExprs, unsigned nargs) 2120 : Expr(ObjCMessageExprClass, retType, false, false), SelName(selInfo), 2121 MethodProto(mproto) { 2122 NumArgs = nargs; 2123 SubExprs = new (C) Stmt*[NumArgs+1]; 2124 SubExprs[RECEIVER] = receiver; 2125 if (NumArgs) { 2126 for (unsigned i = 0; i != NumArgs; ++i) 2127 SubExprs[i+ARGS_START] = static_cast<Expr *>(ArgExprs[i]); 2128 } 2129 LBracloc = LBrac; 2130 RBracloc = RBrac; 2131} 2132 2133// constructor for class messages. 2134// FIXME: clsName should be typed to ObjCInterfaceType 2135ObjCMessageExpr::ObjCMessageExpr(ASTContext &C, IdentifierInfo *clsName, 2136 SourceLocation clsNameLoc, Selector selInfo, 2137 QualType retType, ObjCMethodDecl *mproto, 2138 SourceLocation LBrac, SourceLocation RBrac, 2139 Expr **ArgExprs, unsigned nargs) 2140 : Expr(ObjCMessageExprClass, retType, false, false), ClassNameLoc(clsNameLoc), 2141 SelName(selInfo), MethodProto(mproto) { 2142 NumArgs = nargs; 2143 SubExprs = new (C) Stmt*[NumArgs+1]; 2144 SubExprs[RECEIVER] = (Expr*) ((uintptr_t) clsName | IsClsMethDeclUnknown); 2145 if (NumArgs) { 2146 for (unsigned i = 0; i != NumArgs; ++i) 2147 SubExprs[i+ARGS_START] = static_cast<Expr *>(ArgExprs[i]); 2148 } 2149 LBracloc = LBrac; 2150 RBracloc = RBrac; 2151} 2152 2153// constructor for class messages. 2154ObjCMessageExpr::ObjCMessageExpr(ASTContext &C, ObjCInterfaceDecl *cls, 2155 SourceLocation clsNameLoc, Selector selInfo, 2156 QualType retType, 2157 ObjCMethodDecl *mproto, SourceLocation LBrac, 2158 SourceLocation RBrac, Expr **ArgExprs, 2159 unsigned nargs) 2160 : Expr(ObjCMessageExprClass, retType, false, false), ClassNameLoc(clsNameLoc), 2161 SelName(selInfo), MethodProto(mproto) 2162{ 2163 NumArgs = nargs; 2164 SubExprs = new (C) Stmt*[NumArgs+1]; 2165 SubExprs[RECEIVER] = (Expr*) ((uintptr_t) cls | IsClsMethDeclKnown); 2166 if (NumArgs) { 2167 for (unsigned i = 0; i != NumArgs; ++i) 2168 SubExprs[i+ARGS_START] = static_cast<Expr *>(ArgExprs[i]); 2169 } 2170 LBracloc = LBrac; 2171 RBracloc = RBrac; 2172} 2173 2174ObjCMessageExpr::ClassInfo ObjCMessageExpr::getClassInfo() const { 2175 uintptr_t x = (uintptr_t) SubExprs[RECEIVER]; 2176 switch (x & Flags) { 2177 default: 2178 assert(false && "Invalid ObjCMessageExpr."); 2179 case IsInstMeth: 2180 return ClassInfo(0, 0, SourceLocation()); 2181 case IsClsMethDeclUnknown: 2182 return ClassInfo(0, (IdentifierInfo*) (x & ~Flags), ClassNameLoc); 2183 case IsClsMethDeclKnown: { 2184 ObjCInterfaceDecl* D = (ObjCInterfaceDecl*) (x & ~Flags); 2185 return ClassInfo(D, D->getIdentifier(), ClassNameLoc); 2186 } 2187 } 2188} 2189 2190void ObjCMessageExpr::setClassInfo(const ObjCMessageExpr::ClassInfo &CI) { 2191 if (CI.Decl == 0 && CI.Name == 0) { 2192 SubExprs[RECEIVER] = (Expr*)((uintptr_t)0 | IsInstMeth); 2193 return; 2194 } 2195 2196 if (CI.Decl == 0) 2197 SubExprs[RECEIVER] = (Expr*)((uintptr_t)CI.Name | IsClsMethDeclUnknown); 2198 else 2199 SubExprs[RECEIVER] = (Expr*)((uintptr_t)CI.Decl | IsClsMethDeclKnown); 2200 ClassNameLoc = CI.Loc; 2201} 2202 2203void ObjCMessageExpr::DoDestroy(ASTContext &C) { 2204 DestroyChildren(C); 2205 if (SubExprs) 2206 C.Deallocate(SubExprs); 2207 this->~ObjCMessageExpr(); 2208 C.Deallocate((void*) this); 2209} 2210 2211bool ChooseExpr::isConditionTrue(ASTContext &C) const { 2212 return getCond()->EvaluateAsInt(C) != 0; 2213} 2214 2215void ShuffleVectorExpr::setExprs(ASTContext &C, Expr ** Exprs, 2216 unsigned NumExprs) { 2217 if (SubExprs) C.Deallocate(SubExprs); 2218 2219 SubExprs = new (C) Stmt* [NumExprs]; 2220 this->NumExprs = NumExprs; 2221 memcpy(SubExprs, Exprs, sizeof(Expr *) * NumExprs); 2222} 2223 2224void ShuffleVectorExpr::DoDestroy(ASTContext& C) { 2225 DestroyChildren(C); 2226 if (SubExprs) C.Deallocate(SubExprs); 2227 this->~ShuffleVectorExpr(); 2228 C.Deallocate(this); 2229} 2230 2231void SizeOfAlignOfExpr::DoDestroy(ASTContext& C) { 2232 // Override default behavior of traversing children. If this has a type 2233 // operand and the type is a variable-length array, the child iteration 2234 // will iterate over the size expression. However, this expression belongs 2235 // to the type, not to this, so we don't want to delete it. 2236 // We still want to delete this expression. 2237 if (isArgumentType()) { 2238 this->~SizeOfAlignOfExpr(); 2239 C.Deallocate(this); 2240 } 2241 else 2242 Expr::DoDestroy(C); 2243} 2244 2245//===----------------------------------------------------------------------===// 2246// DesignatedInitExpr 2247//===----------------------------------------------------------------------===// 2248 2249IdentifierInfo *DesignatedInitExpr::Designator::getFieldName() { 2250 assert(Kind == FieldDesignator && "Only valid on a field designator"); 2251 if (Field.NameOrField & 0x01) 2252 return reinterpret_cast<IdentifierInfo *>(Field.NameOrField&~0x01); 2253 else 2254 return getField()->getIdentifier(); 2255} 2256 2257DesignatedInitExpr::DesignatedInitExpr(ASTContext &C, QualType Ty, 2258 unsigned NumDesignators, 2259 const Designator *Designators, 2260 SourceLocation EqualOrColonLoc, 2261 bool GNUSyntax, 2262 Expr **IndexExprs, 2263 unsigned NumIndexExprs, 2264 Expr *Init) 2265 : Expr(DesignatedInitExprClass, Ty, 2266 Init->isTypeDependent(), Init->isValueDependent()), 2267 EqualOrColonLoc(EqualOrColonLoc), GNUSyntax(GNUSyntax), 2268 NumDesignators(NumDesignators), NumSubExprs(NumIndexExprs + 1) { 2269 this->Designators = new (C) Designator[NumDesignators]; 2270 2271 // Record the initializer itself. 2272 child_iterator Child = child_begin(); 2273 *Child++ = Init; 2274 2275 // Copy the designators and their subexpressions, computing 2276 // value-dependence along the way. 2277 unsigned IndexIdx = 0; 2278 for (unsigned I = 0; I != NumDesignators; ++I) { 2279 this->Designators[I] = Designators[I]; 2280 2281 if (this->Designators[I].isArrayDesignator()) { 2282 // Compute type- and value-dependence. 2283 Expr *Index = IndexExprs[IndexIdx]; 2284 ValueDependent = ValueDependent || 2285 Index->isTypeDependent() || Index->isValueDependent(); 2286 2287 // Copy the index expressions into permanent storage. 2288 *Child++ = IndexExprs[IndexIdx++]; 2289 } else if (this->Designators[I].isArrayRangeDesignator()) { 2290 // Compute type- and value-dependence. 2291 Expr *Start = IndexExprs[IndexIdx]; 2292 Expr *End = IndexExprs[IndexIdx + 1]; 2293 ValueDependent = ValueDependent || 2294 Start->isTypeDependent() || Start->isValueDependent() || 2295 End->isTypeDependent() || End->isValueDependent(); 2296 2297 // Copy the start/end expressions into permanent storage. 2298 *Child++ = IndexExprs[IndexIdx++]; 2299 *Child++ = IndexExprs[IndexIdx++]; 2300 } 2301 } 2302 2303 assert(IndexIdx == NumIndexExprs && "Wrong number of index expressions"); 2304} 2305 2306DesignatedInitExpr * 2307DesignatedInitExpr::Create(ASTContext &C, Designator *Designators, 2308 unsigned NumDesignators, 2309 Expr **IndexExprs, unsigned NumIndexExprs, 2310 SourceLocation ColonOrEqualLoc, 2311 bool UsesColonSyntax, Expr *Init) { 2312 void *Mem = C.Allocate(sizeof(DesignatedInitExpr) + 2313 sizeof(Stmt *) * (NumIndexExprs + 1), 8); 2314 return new (Mem) DesignatedInitExpr(C, C.VoidTy, NumDesignators, Designators, 2315 ColonOrEqualLoc, UsesColonSyntax, 2316 IndexExprs, NumIndexExprs, Init); 2317} 2318 2319DesignatedInitExpr *DesignatedInitExpr::CreateEmpty(ASTContext &C, 2320 unsigned NumIndexExprs) { 2321 void *Mem = C.Allocate(sizeof(DesignatedInitExpr) + 2322 sizeof(Stmt *) * (NumIndexExprs + 1), 8); 2323 return new (Mem) DesignatedInitExpr(NumIndexExprs + 1); 2324} 2325 2326void DesignatedInitExpr::setDesignators(ASTContext &C, 2327 const Designator *Desigs, 2328 unsigned NumDesigs) { 2329 DestroyDesignators(C); 2330 2331 Designators = new (C) Designator[NumDesigs]; 2332 NumDesignators = NumDesigs; 2333 for (unsigned I = 0; I != NumDesigs; ++I) 2334 Designators[I] = Desigs[I]; 2335} 2336 2337SourceRange DesignatedInitExpr::getSourceRange() const { 2338 SourceLocation StartLoc; 2339 Designator &First = 2340 *const_cast<DesignatedInitExpr*>(this)->designators_begin(); 2341 if (First.isFieldDesignator()) { 2342 if (GNUSyntax) 2343 StartLoc = SourceLocation::getFromRawEncoding(First.Field.FieldLoc); 2344 else 2345 StartLoc = SourceLocation::getFromRawEncoding(First.Field.DotLoc); 2346 } else 2347 StartLoc = 2348 SourceLocation::getFromRawEncoding(First.ArrayOrRange.LBracketLoc); 2349 return SourceRange(StartLoc, getInit()->getSourceRange().getEnd()); 2350} 2351 2352Expr *DesignatedInitExpr::getArrayIndex(const Designator& D) { 2353 assert(D.Kind == Designator::ArrayDesignator && "Requires array designator"); 2354 char* Ptr = static_cast<char*>(static_cast<void *>(this)); 2355 Ptr += sizeof(DesignatedInitExpr); 2356 Stmt **SubExprs = reinterpret_cast<Stmt**>(reinterpret_cast<void**>(Ptr)); 2357 return cast<Expr>(*(SubExprs + D.ArrayOrRange.Index + 1)); 2358} 2359 2360Expr *DesignatedInitExpr::getArrayRangeStart(const Designator& D) { 2361 assert(D.Kind == Designator::ArrayRangeDesignator && 2362 "Requires array range designator"); 2363 char* Ptr = static_cast<char*>(static_cast<void *>(this)); 2364 Ptr += sizeof(DesignatedInitExpr); 2365 Stmt **SubExprs = reinterpret_cast<Stmt**>(reinterpret_cast<void**>(Ptr)); 2366 return cast<Expr>(*(SubExprs + D.ArrayOrRange.Index + 1)); 2367} 2368 2369Expr *DesignatedInitExpr::getArrayRangeEnd(const Designator& D) { 2370 assert(D.Kind == Designator::ArrayRangeDesignator && 2371 "Requires array range designator"); 2372 char* Ptr = static_cast<char*>(static_cast<void *>(this)); 2373 Ptr += sizeof(DesignatedInitExpr); 2374 Stmt **SubExprs = reinterpret_cast<Stmt**>(reinterpret_cast<void**>(Ptr)); 2375 return cast<Expr>(*(SubExprs + D.ArrayOrRange.Index + 2)); 2376} 2377 2378/// \brief Replaces the designator at index @p Idx with the series 2379/// of designators in [First, Last). 2380void DesignatedInitExpr::ExpandDesignator(ASTContext &C, unsigned Idx, 2381 const Designator *First, 2382 const Designator *Last) { 2383 unsigned NumNewDesignators = Last - First; 2384 if (NumNewDesignators == 0) { 2385 std::copy_backward(Designators + Idx + 1, 2386 Designators + NumDesignators, 2387 Designators + Idx); 2388 --NumNewDesignators; 2389 return; 2390 } else if (NumNewDesignators == 1) { 2391 Designators[Idx] = *First; 2392 return; 2393 } 2394 2395 Designator *NewDesignators 2396 = new (C) Designator[NumDesignators - 1 + NumNewDesignators]; 2397 std::copy(Designators, Designators + Idx, NewDesignators); 2398 std::copy(First, Last, NewDesignators + Idx); 2399 std::copy(Designators + Idx + 1, Designators + NumDesignators, 2400 NewDesignators + Idx + NumNewDesignators); 2401 DestroyDesignators(C); 2402 Designators = NewDesignators; 2403 NumDesignators = NumDesignators - 1 + NumNewDesignators; 2404} 2405 2406void DesignatedInitExpr::DoDestroy(ASTContext &C) { 2407 DestroyDesignators(C); 2408 Expr::DoDestroy(C); 2409} 2410 2411void DesignatedInitExpr::DestroyDesignators(ASTContext &C) { 2412 for (unsigned I = 0; I != NumDesignators; ++I) 2413 Designators[I].~Designator(); 2414 C.Deallocate(Designators); 2415 Designators = 0; 2416} 2417 2418ParenListExpr::ParenListExpr(ASTContext& C, SourceLocation lparenloc, 2419 Expr **exprs, unsigned nexprs, 2420 SourceLocation rparenloc) 2421: Expr(ParenListExprClass, QualType(), 2422 hasAnyTypeDependentArguments(exprs, nexprs), 2423 hasAnyValueDependentArguments(exprs, nexprs)), 2424 NumExprs(nexprs), LParenLoc(lparenloc), RParenLoc(rparenloc) { 2425 2426 Exprs = new (C) Stmt*[nexprs]; 2427 for (unsigned i = 0; i != nexprs; ++i) 2428 Exprs[i] = exprs[i]; 2429} 2430 2431void ParenListExpr::DoDestroy(ASTContext& C) { 2432 DestroyChildren(C); 2433 if (Exprs) C.Deallocate(Exprs); 2434 this->~ParenListExpr(); 2435 C.Deallocate(this); 2436} 2437 2438//===----------------------------------------------------------------------===// 2439// ExprIterator. 2440//===----------------------------------------------------------------------===// 2441 2442Expr* ExprIterator::operator[](size_t idx) { return cast<Expr>(I[idx]); } 2443Expr* ExprIterator::operator*() const { return cast<Expr>(*I); } 2444Expr* ExprIterator::operator->() const { return cast<Expr>(*I); } 2445const Expr* ConstExprIterator::operator[](size_t idx) const { 2446 return cast<Expr>(I[idx]); 2447} 2448const Expr* ConstExprIterator::operator*() const { return cast<Expr>(*I); } 2449const Expr* ConstExprIterator::operator->() const { return cast<Expr>(*I); } 2450 2451//===----------------------------------------------------------------------===// 2452// Child Iterators for iterating over subexpressions/substatements 2453//===----------------------------------------------------------------------===// 2454 2455// DeclRefExpr 2456Stmt::child_iterator DeclRefExpr::child_begin() { return child_iterator(); } 2457Stmt::child_iterator DeclRefExpr::child_end() { return child_iterator(); } 2458 2459// ObjCIvarRefExpr 2460Stmt::child_iterator ObjCIvarRefExpr::child_begin() { return &Base; } 2461Stmt::child_iterator ObjCIvarRefExpr::child_end() { return &Base+1; } 2462 2463// ObjCPropertyRefExpr 2464Stmt::child_iterator ObjCPropertyRefExpr::child_begin() { return &Base; } 2465Stmt::child_iterator ObjCPropertyRefExpr::child_end() { return &Base+1; } 2466 2467// ObjCImplicitSetterGetterRefExpr 2468Stmt::child_iterator ObjCImplicitSetterGetterRefExpr::child_begin() { 2469 return &Base; 2470} 2471Stmt::child_iterator ObjCImplicitSetterGetterRefExpr::child_end() { 2472 return &Base+1; 2473} 2474 2475// ObjCSuperExpr 2476Stmt::child_iterator ObjCSuperExpr::child_begin() { return child_iterator(); } 2477Stmt::child_iterator ObjCSuperExpr::child_end() { return child_iterator(); } 2478 2479// ObjCIsaExpr 2480Stmt::child_iterator ObjCIsaExpr::child_begin() { return &Base; } 2481Stmt::child_iterator ObjCIsaExpr::child_end() { return &Base+1; } 2482 2483// PredefinedExpr 2484Stmt::child_iterator PredefinedExpr::child_begin() { return child_iterator(); } 2485Stmt::child_iterator PredefinedExpr::child_end() { return child_iterator(); } 2486 2487// IntegerLiteral 2488Stmt::child_iterator IntegerLiteral::child_begin() { return child_iterator(); } 2489Stmt::child_iterator IntegerLiteral::child_end() { return child_iterator(); } 2490 2491// CharacterLiteral 2492Stmt::child_iterator CharacterLiteral::child_begin() { return child_iterator();} 2493Stmt::child_iterator CharacterLiteral::child_end() { return child_iterator(); } 2494 2495// FloatingLiteral 2496Stmt::child_iterator FloatingLiteral::child_begin() { return child_iterator(); } 2497Stmt::child_iterator FloatingLiteral::child_end() { return child_iterator(); } 2498 2499// ImaginaryLiteral 2500Stmt::child_iterator ImaginaryLiteral::child_begin() { return &Val; } 2501Stmt::child_iterator ImaginaryLiteral::child_end() { return &Val+1; } 2502 2503// StringLiteral 2504Stmt::child_iterator StringLiteral::child_begin() { return child_iterator(); } 2505Stmt::child_iterator StringLiteral::child_end() { return child_iterator(); } 2506 2507// ParenExpr 2508Stmt::child_iterator ParenExpr::child_begin() { return &Val; } 2509Stmt::child_iterator ParenExpr::child_end() { return &Val+1; } 2510 2511// UnaryOperator 2512Stmt::child_iterator UnaryOperator::child_begin() { return &Val; } 2513Stmt::child_iterator UnaryOperator::child_end() { return &Val+1; } 2514 2515// SizeOfAlignOfExpr 2516Stmt::child_iterator SizeOfAlignOfExpr::child_begin() { 2517 // If this is of a type and the type is a VLA type (and not a typedef), the 2518 // size expression of the VLA needs to be treated as an executable expression. 2519 // Why isn't this weirdness documented better in StmtIterator? 2520 if (isArgumentType()) { 2521 if (VariableArrayType* T = dyn_cast<VariableArrayType>( 2522 getArgumentType().getTypePtr())) 2523 return child_iterator(T); 2524 return child_iterator(); 2525 } 2526 return child_iterator(&Argument.Ex); 2527} 2528Stmt::child_iterator SizeOfAlignOfExpr::child_end() { 2529 if (isArgumentType()) 2530 return child_iterator(); 2531 return child_iterator(&Argument.Ex + 1); 2532} 2533 2534// ArraySubscriptExpr 2535Stmt::child_iterator ArraySubscriptExpr::child_begin() { 2536 return &SubExprs[0]; 2537} 2538Stmt::child_iterator ArraySubscriptExpr::child_end() { 2539 return &SubExprs[0]+END_EXPR; 2540} 2541 2542// CallExpr 2543Stmt::child_iterator CallExpr::child_begin() { 2544 return &SubExprs[0]; 2545} 2546Stmt::child_iterator CallExpr::child_end() { 2547 return &SubExprs[0]+NumArgs+ARGS_START; 2548} 2549 2550// MemberExpr 2551Stmt::child_iterator MemberExpr::child_begin() { return &Base; } 2552Stmt::child_iterator MemberExpr::child_end() { return &Base+1; } 2553 2554// ExtVectorElementExpr 2555Stmt::child_iterator ExtVectorElementExpr::child_begin() { return &Base; } 2556Stmt::child_iterator ExtVectorElementExpr::child_end() { return &Base+1; } 2557 2558// CompoundLiteralExpr 2559Stmt::child_iterator CompoundLiteralExpr::child_begin() { return &Init; } 2560Stmt::child_iterator CompoundLiteralExpr::child_end() { return &Init+1; } 2561 2562// CastExpr 2563Stmt::child_iterator CastExpr::child_begin() { return &Op; } 2564Stmt::child_iterator CastExpr::child_end() { return &Op+1; } 2565 2566// BinaryOperator 2567Stmt::child_iterator BinaryOperator::child_begin() { 2568 return &SubExprs[0]; 2569} 2570Stmt::child_iterator BinaryOperator::child_end() { 2571 return &SubExprs[0]+END_EXPR; 2572} 2573 2574// ConditionalOperator 2575Stmt::child_iterator ConditionalOperator::child_begin() { 2576 return &SubExprs[0]; 2577} 2578Stmt::child_iterator ConditionalOperator::child_end() { 2579 return &SubExprs[0]+END_EXPR; 2580} 2581 2582// AddrLabelExpr 2583Stmt::child_iterator AddrLabelExpr::child_begin() { return child_iterator(); } 2584Stmt::child_iterator AddrLabelExpr::child_end() { return child_iterator(); } 2585 2586// StmtExpr 2587Stmt::child_iterator StmtExpr::child_begin() { return &SubStmt; } 2588Stmt::child_iterator StmtExpr::child_end() { return &SubStmt+1; } 2589 2590// TypesCompatibleExpr 2591Stmt::child_iterator TypesCompatibleExpr::child_begin() { 2592 return child_iterator(); 2593} 2594 2595Stmt::child_iterator TypesCompatibleExpr::child_end() { 2596 return child_iterator(); 2597} 2598 2599// ChooseExpr 2600Stmt::child_iterator ChooseExpr::child_begin() { return &SubExprs[0]; } 2601Stmt::child_iterator ChooseExpr::child_end() { return &SubExprs[0]+END_EXPR; } 2602 2603// GNUNullExpr 2604Stmt::child_iterator GNUNullExpr::child_begin() { return child_iterator(); } 2605Stmt::child_iterator GNUNullExpr::child_end() { return child_iterator(); } 2606 2607// ShuffleVectorExpr 2608Stmt::child_iterator ShuffleVectorExpr::child_begin() { 2609 return &SubExprs[0]; 2610} 2611Stmt::child_iterator ShuffleVectorExpr::child_end() { 2612 return &SubExprs[0]+NumExprs; 2613} 2614 2615// VAArgExpr 2616Stmt::child_iterator VAArgExpr::child_begin() { return &Val; } 2617Stmt::child_iterator VAArgExpr::child_end() { return &Val+1; } 2618 2619// InitListExpr 2620Stmt::child_iterator InitListExpr::child_begin() { 2621 return InitExprs.size() ? &InitExprs[0] : 0; 2622} 2623Stmt::child_iterator InitListExpr::child_end() { 2624 return InitExprs.size() ? &InitExprs[0] + InitExprs.size() : 0; 2625} 2626 2627// DesignatedInitExpr 2628Stmt::child_iterator DesignatedInitExpr::child_begin() { 2629 char* Ptr = static_cast<char*>(static_cast<void *>(this)); 2630 Ptr += sizeof(DesignatedInitExpr); 2631 return reinterpret_cast<Stmt**>(reinterpret_cast<void**>(Ptr)); 2632} 2633Stmt::child_iterator DesignatedInitExpr::child_end() { 2634 return child_iterator(&*child_begin() + NumSubExprs); 2635} 2636 2637// ImplicitValueInitExpr 2638Stmt::child_iterator ImplicitValueInitExpr::child_begin() { 2639 return child_iterator(); 2640} 2641 2642Stmt::child_iterator ImplicitValueInitExpr::child_end() { 2643 return child_iterator(); 2644} 2645 2646// ParenListExpr 2647Stmt::child_iterator ParenListExpr::child_begin() { 2648 return &Exprs[0]; 2649} 2650Stmt::child_iterator ParenListExpr::child_end() { 2651 return &Exprs[0]+NumExprs; 2652} 2653 2654// ObjCStringLiteral 2655Stmt::child_iterator ObjCStringLiteral::child_begin() { 2656 return &String; 2657} 2658Stmt::child_iterator ObjCStringLiteral::child_end() { 2659 return &String+1; 2660} 2661 2662// ObjCEncodeExpr 2663Stmt::child_iterator ObjCEncodeExpr::child_begin() { return child_iterator(); } 2664Stmt::child_iterator ObjCEncodeExpr::child_end() { return child_iterator(); } 2665 2666// ObjCSelectorExpr 2667Stmt::child_iterator ObjCSelectorExpr::child_begin() { 2668 return child_iterator(); 2669} 2670Stmt::child_iterator ObjCSelectorExpr::child_end() { 2671 return child_iterator(); 2672} 2673 2674// ObjCProtocolExpr 2675Stmt::child_iterator ObjCProtocolExpr::child_begin() { 2676 return child_iterator(); 2677} 2678Stmt::child_iterator ObjCProtocolExpr::child_end() { 2679 return child_iterator(); 2680} 2681 2682// ObjCMessageExpr 2683Stmt::child_iterator ObjCMessageExpr::child_begin() { 2684 return getReceiver() ? &SubExprs[0] : &SubExprs[0] + ARGS_START; 2685} 2686Stmt::child_iterator ObjCMessageExpr::child_end() { 2687 return &SubExprs[0]+ARGS_START+getNumArgs(); 2688} 2689 2690// Blocks 2691Stmt::child_iterator BlockExpr::child_begin() { return child_iterator(); } 2692Stmt::child_iterator BlockExpr::child_end() { return child_iterator(); } 2693 2694Stmt::child_iterator BlockDeclRefExpr::child_begin() { return child_iterator();} 2695Stmt::child_iterator BlockDeclRefExpr::child_end() { return child_iterator(); } 2696