Expr.cpp revision b03d33edaf24af2893a50caee4d2c99839242c44
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(Expr *base, bool isarrow, NestedNameSpecifier *qual, 496 SourceRange qualrange, ValueDecl *memberdecl, 497 SourceLocation l, const TemplateArgumentListInfo *targs, 498 QualType ty) 499 : Expr(MemberExprClass, ty, 500 base->isTypeDependent() || (qual && qual->isDependent()), 501 base->isValueDependent() || (qual && qual->isDependent())), 502 Base(base), MemberDecl(memberdecl), MemberLoc(l), IsArrow(isarrow), 503 HasQualifier(qual != 0), HasExplicitTemplateArgumentList(targs) { 504 // Initialize the qualifier, if any. 505 if (HasQualifier) { 506 NameQualifier *NQ = getMemberQualifier(); 507 NQ->NNS = qual; 508 NQ->Range = qualrange; 509 } 510 511 // Initialize the explicit template argument list, if any. 512 if (targs) 513 getExplicitTemplateArgumentList()->initializeFrom(*targs); 514} 515 516MemberExpr *MemberExpr::Create(ASTContext &C, Expr *base, bool isarrow, 517 NestedNameSpecifier *qual, 518 SourceRange qualrange, 519 ValueDecl *memberdecl, 520 SourceLocation l, 521 const TemplateArgumentListInfo *targs, 522 QualType ty) { 523 std::size_t Size = sizeof(MemberExpr); 524 if (qual != 0) 525 Size += sizeof(NameQualifier); 526 527 if (targs) 528 Size += ExplicitTemplateArgumentList::sizeFor(*targs); 529 530 void *Mem = C.Allocate(Size, llvm::alignof<MemberExpr>()); 531 return new (Mem) MemberExpr(base, isarrow, qual, qualrange, memberdecl, l, 532 targs, ty); 533} 534 535const char *CastExpr::getCastKindName() const { 536 switch (getCastKind()) { 537 case CastExpr::CK_Unknown: 538 return "Unknown"; 539 case CastExpr::CK_BitCast: 540 return "BitCast"; 541 case CastExpr::CK_NoOp: 542 return "NoOp"; 543 case CastExpr::CK_BaseToDerived: 544 return "BaseToDerived"; 545 case CastExpr::CK_DerivedToBase: 546 return "DerivedToBase"; 547 case CastExpr::CK_Dynamic: 548 return "Dynamic"; 549 case CastExpr::CK_ToUnion: 550 return "ToUnion"; 551 case CastExpr::CK_ArrayToPointerDecay: 552 return "ArrayToPointerDecay"; 553 case CastExpr::CK_FunctionToPointerDecay: 554 return "FunctionToPointerDecay"; 555 case CastExpr::CK_NullToMemberPointer: 556 return "NullToMemberPointer"; 557 case CastExpr::CK_BaseToDerivedMemberPointer: 558 return "BaseToDerivedMemberPointer"; 559 case CastExpr::CK_DerivedToBaseMemberPointer: 560 return "DerivedToBaseMemberPointer"; 561 case CastExpr::CK_UserDefinedConversion: 562 return "UserDefinedConversion"; 563 case CastExpr::CK_ConstructorConversion: 564 return "ConstructorConversion"; 565 case CastExpr::CK_IntegralToPointer: 566 return "IntegralToPointer"; 567 case CastExpr::CK_PointerToIntegral: 568 return "PointerToIntegral"; 569 case CastExpr::CK_ToVoid: 570 return "ToVoid"; 571 case CastExpr::CK_VectorSplat: 572 return "VectorSplat"; 573 case CastExpr::CK_IntegralCast: 574 return "IntegralCast"; 575 case CastExpr::CK_IntegralToFloating: 576 return "IntegralToFloating"; 577 case CastExpr::CK_FloatingToIntegral: 578 return "FloatingToIntegral"; 579 case CastExpr::CK_FloatingCast: 580 return "FloatingCast"; 581 case CastExpr::CK_MemberPointerToBoolean: 582 return "MemberPointerToBoolean"; 583 case CastExpr::CK_AnyPointerToObjCPointerCast: 584 return "AnyPointerToObjCPointerCast"; 585 case CastExpr::CK_AnyPointerToBlockPointerCast: 586 return "AnyPointerToBlockPointerCast"; 587 } 588 589 assert(0 && "Unhandled cast kind!"); 590 return 0; 591} 592 593Expr *CastExpr::getSubExprAsWritten() { 594 Expr *SubExpr = 0; 595 CastExpr *E = this; 596 do { 597 SubExpr = E->getSubExpr(); 598 599 // Skip any temporary bindings; they're implicit. 600 if (CXXBindTemporaryExpr *Binder = dyn_cast<CXXBindTemporaryExpr>(SubExpr)) 601 SubExpr = Binder->getSubExpr(); 602 603 // Conversions by constructor and conversion functions have a 604 // subexpression describing the call; strip it off. 605 if (E->getCastKind() == CastExpr::CK_ConstructorConversion) 606 SubExpr = cast<CXXConstructExpr>(SubExpr)->getArg(0); 607 else if (E->getCastKind() == CastExpr::CK_UserDefinedConversion) 608 SubExpr = cast<CXXMemberCallExpr>(SubExpr)->getImplicitObjectArgument(); 609 610 // If the subexpression we're left with is an implicit cast, look 611 // through that, too. 612 } while ((E = dyn_cast<ImplicitCastExpr>(SubExpr))); 613 614 return SubExpr; 615} 616 617/// getOpcodeStr - Turn an Opcode enum value into the punctuation char it 618/// corresponds to, e.g. "<<=". 619const char *BinaryOperator::getOpcodeStr(Opcode Op) { 620 switch (Op) { 621 case PtrMemD: return ".*"; 622 case PtrMemI: return "->*"; 623 case Mul: return "*"; 624 case Div: return "/"; 625 case Rem: return "%"; 626 case Add: return "+"; 627 case Sub: return "-"; 628 case Shl: return "<<"; 629 case Shr: return ">>"; 630 case LT: return "<"; 631 case GT: return ">"; 632 case LE: return "<="; 633 case GE: return ">="; 634 case EQ: return "=="; 635 case NE: return "!="; 636 case And: return "&"; 637 case Xor: return "^"; 638 case Or: return "|"; 639 case LAnd: return "&&"; 640 case LOr: return "||"; 641 case Assign: return "="; 642 case MulAssign: return "*="; 643 case DivAssign: return "/="; 644 case RemAssign: return "%="; 645 case AddAssign: return "+="; 646 case SubAssign: return "-="; 647 case ShlAssign: return "<<="; 648 case ShrAssign: return ">>="; 649 case AndAssign: return "&="; 650 case XorAssign: return "^="; 651 case OrAssign: return "|="; 652 case Comma: return ","; 653 } 654 655 return ""; 656} 657 658BinaryOperator::Opcode 659BinaryOperator::getOverloadedOpcode(OverloadedOperatorKind OO) { 660 switch (OO) { 661 default: assert(false && "Not an overloadable binary operator"); 662 case OO_Plus: return Add; 663 case OO_Minus: return Sub; 664 case OO_Star: return Mul; 665 case OO_Slash: return Div; 666 case OO_Percent: return Rem; 667 case OO_Caret: return Xor; 668 case OO_Amp: return And; 669 case OO_Pipe: return Or; 670 case OO_Equal: return Assign; 671 case OO_Less: return LT; 672 case OO_Greater: return GT; 673 case OO_PlusEqual: return AddAssign; 674 case OO_MinusEqual: return SubAssign; 675 case OO_StarEqual: return MulAssign; 676 case OO_SlashEqual: return DivAssign; 677 case OO_PercentEqual: return RemAssign; 678 case OO_CaretEqual: return XorAssign; 679 case OO_AmpEqual: return AndAssign; 680 case OO_PipeEqual: return OrAssign; 681 case OO_LessLess: return Shl; 682 case OO_GreaterGreater: return Shr; 683 case OO_LessLessEqual: return ShlAssign; 684 case OO_GreaterGreaterEqual: return ShrAssign; 685 case OO_EqualEqual: return EQ; 686 case OO_ExclaimEqual: return NE; 687 case OO_LessEqual: return LE; 688 case OO_GreaterEqual: return GE; 689 case OO_AmpAmp: return LAnd; 690 case OO_PipePipe: return LOr; 691 case OO_Comma: return Comma; 692 case OO_ArrowStar: return PtrMemI; 693 } 694} 695 696OverloadedOperatorKind BinaryOperator::getOverloadedOperator(Opcode Opc) { 697 static const OverloadedOperatorKind OverOps[] = { 698 /* .* Cannot be overloaded */OO_None, OO_ArrowStar, 699 OO_Star, OO_Slash, OO_Percent, 700 OO_Plus, OO_Minus, 701 OO_LessLess, OO_GreaterGreater, 702 OO_Less, OO_Greater, OO_LessEqual, OO_GreaterEqual, 703 OO_EqualEqual, OO_ExclaimEqual, 704 OO_Amp, 705 OO_Caret, 706 OO_Pipe, 707 OO_AmpAmp, 708 OO_PipePipe, 709 OO_Equal, OO_StarEqual, 710 OO_SlashEqual, OO_PercentEqual, 711 OO_PlusEqual, OO_MinusEqual, 712 OO_LessLessEqual, OO_GreaterGreaterEqual, 713 OO_AmpEqual, OO_CaretEqual, 714 OO_PipeEqual, 715 OO_Comma 716 }; 717 return OverOps[Opc]; 718} 719 720InitListExpr::InitListExpr(SourceLocation lbraceloc, 721 Expr **initExprs, unsigned numInits, 722 SourceLocation rbraceloc) 723 : Expr(InitListExprClass, QualType(), false, false), 724 LBraceLoc(lbraceloc), RBraceLoc(rbraceloc), SyntacticForm(0), 725 UnionFieldInit(0), HadArrayRangeDesignator(false) 726{ 727 for (unsigned I = 0; I != numInits; ++I) { 728 if (initExprs[I]->isTypeDependent()) 729 TypeDependent = true; 730 if (initExprs[I]->isValueDependent()) 731 ValueDependent = true; 732 } 733 734 InitExprs.insert(InitExprs.end(), initExprs, initExprs+numInits); 735} 736 737void InitListExpr::reserveInits(unsigned NumInits) { 738 if (NumInits > InitExprs.size()) 739 InitExprs.reserve(NumInits); 740} 741 742void InitListExpr::resizeInits(ASTContext &Context, unsigned NumInits) { 743 for (unsigned Idx = NumInits, LastIdx = InitExprs.size(); 744 Idx < LastIdx; ++Idx) 745 InitExprs[Idx]->Destroy(Context); 746 InitExprs.resize(NumInits, 0); 747} 748 749Expr *InitListExpr::updateInit(unsigned Init, Expr *expr) { 750 if (Init >= InitExprs.size()) { 751 InitExprs.insert(InitExprs.end(), Init - InitExprs.size() + 1, 0); 752 InitExprs.back() = expr; 753 return 0; 754 } 755 756 Expr *Result = cast_or_null<Expr>(InitExprs[Init]); 757 InitExprs[Init] = expr; 758 return Result; 759} 760 761/// getFunctionType - Return the underlying function type for this block. 762/// 763const FunctionType *BlockExpr::getFunctionType() const { 764 return getType()->getAs<BlockPointerType>()-> 765 getPointeeType()->getAs<FunctionType>(); 766} 767 768SourceLocation BlockExpr::getCaretLocation() const { 769 return TheBlock->getCaretLocation(); 770} 771const Stmt *BlockExpr::getBody() const { 772 return TheBlock->getBody(); 773} 774Stmt *BlockExpr::getBody() { 775 return TheBlock->getBody(); 776} 777 778 779//===----------------------------------------------------------------------===// 780// Generic Expression Routines 781//===----------------------------------------------------------------------===// 782 783/// isUnusedResultAWarning - Return true if this immediate expression should 784/// be warned about if the result is unused. If so, fill in Loc and Ranges 785/// with location to warn on and the source range[s] to report with the 786/// warning. 787bool Expr::isUnusedResultAWarning(SourceLocation &Loc, SourceRange &R1, 788 SourceRange &R2, ASTContext &Ctx) const { 789 // Don't warn if the expr is type dependent. The type could end up 790 // instantiating to void. 791 if (isTypeDependent()) 792 return false; 793 794 switch (getStmtClass()) { 795 default: 796 if (getType()->isVoidType()) 797 return false; 798 Loc = getExprLoc(); 799 R1 = getSourceRange(); 800 return true; 801 case ParenExprClass: 802 return cast<ParenExpr>(this)->getSubExpr()-> 803 isUnusedResultAWarning(Loc, R1, R2, Ctx); 804 case UnaryOperatorClass: { 805 const UnaryOperator *UO = cast<UnaryOperator>(this); 806 807 switch (UO->getOpcode()) { 808 default: break; 809 case UnaryOperator::PostInc: 810 case UnaryOperator::PostDec: 811 case UnaryOperator::PreInc: 812 case UnaryOperator::PreDec: // ++/-- 813 return false; // Not a warning. 814 case UnaryOperator::Deref: 815 // Dereferencing a volatile pointer is a side-effect. 816 if (Ctx.getCanonicalType(getType()).isVolatileQualified()) 817 return false; 818 break; 819 case UnaryOperator::Real: 820 case UnaryOperator::Imag: 821 // accessing a piece of a volatile complex is a side-effect. 822 if (Ctx.getCanonicalType(UO->getSubExpr()->getType()) 823 .isVolatileQualified()) 824 return false; 825 break; 826 case UnaryOperator::Extension: 827 return UO->getSubExpr()->isUnusedResultAWarning(Loc, R1, R2, Ctx); 828 } 829 Loc = UO->getOperatorLoc(); 830 R1 = UO->getSubExpr()->getSourceRange(); 831 return true; 832 } 833 case BinaryOperatorClass: { 834 const BinaryOperator *BO = cast<BinaryOperator>(this); 835 // Consider comma to have side effects if the LHS or RHS does. 836 if (BO->getOpcode() == BinaryOperator::Comma) { 837 // ((foo = <blah>), 0) is an idiom for hiding the result (and 838 // lvalue-ness) of an assignment written in a macro. 839 if (IntegerLiteral *IE = 840 dyn_cast<IntegerLiteral>(BO->getRHS()->IgnoreParens())) 841 if (IE->getValue() == 0) 842 return false; 843 844 return (BO->getLHS()->isUnusedResultAWarning(Loc, R1, R2, Ctx) || 845 BO->getRHS()->isUnusedResultAWarning(Loc, R1, R2, Ctx)); 846 } 847 848 if (BO->isAssignmentOp()) 849 return false; 850 Loc = BO->getOperatorLoc(); 851 R1 = BO->getLHS()->getSourceRange(); 852 R2 = BO->getRHS()->getSourceRange(); 853 return true; 854 } 855 case CompoundAssignOperatorClass: 856 return false; 857 858 case ConditionalOperatorClass: { 859 // The condition must be evaluated, but if either the LHS or RHS is a 860 // warning, warn about them. 861 const ConditionalOperator *Exp = cast<ConditionalOperator>(this); 862 if (Exp->getLHS() && 863 Exp->getLHS()->isUnusedResultAWarning(Loc, R1, R2, Ctx)) 864 return true; 865 return Exp->getRHS()->isUnusedResultAWarning(Loc, R1, R2, Ctx); 866 } 867 868 case MemberExprClass: 869 // If the base pointer or element is to a volatile pointer/field, accessing 870 // it is a side effect. 871 if (Ctx.getCanonicalType(getType()).isVolatileQualified()) 872 return false; 873 Loc = cast<MemberExpr>(this)->getMemberLoc(); 874 R1 = SourceRange(Loc, Loc); 875 R2 = cast<MemberExpr>(this)->getBase()->getSourceRange(); 876 return true; 877 878 case ArraySubscriptExprClass: 879 // If the base pointer or element is to a volatile pointer/field, accessing 880 // it is a side effect. 881 if (Ctx.getCanonicalType(getType()).isVolatileQualified()) 882 return false; 883 Loc = cast<ArraySubscriptExpr>(this)->getRBracketLoc(); 884 R1 = cast<ArraySubscriptExpr>(this)->getLHS()->getSourceRange(); 885 R2 = cast<ArraySubscriptExpr>(this)->getRHS()->getSourceRange(); 886 return true; 887 888 case CallExprClass: 889 case CXXOperatorCallExprClass: 890 case CXXMemberCallExprClass: { 891 // If this is a direct call, get the callee. 892 const CallExpr *CE = cast<CallExpr>(this); 893 if (const Decl *FD = CE->getCalleeDecl()) { 894 // If the callee has attribute pure, const, or warn_unused_result, warn 895 // about it. void foo() { strlen("bar"); } should warn. 896 // 897 // Note: If new cases are added here, DiagnoseUnusedExprResult should be 898 // updated to match for QoI. 899 if (FD->getAttr<WarnUnusedResultAttr>() || 900 FD->getAttr<PureAttr>() || FD->getAttr<ConstAttr>()) { 901 Loc = CE->getCallee()->getLocStart(); 902 R1 = CE->getCallee()->getSourceRange(); 903 904 if (unsigned NumArgs = CE->getNumArgs()) 905 R2 = SourceRange(CE->getArg(0)->getLocStart(), 906 CE->getArg(NumArgs-1)->getLocEnd()); 907 return true; 908 } 909 } 910 return false; 911 } 912 913 case CXXTemporaryObjectExprClass: 914 case CXXConstructExprClass: 915 return false; 916 917 case ObjCMessageExprClass: 918 return false; 919 920 case ObjCImplicitSetterGetterRefExprClass: { // Dot syntax for message send. 921#if 0 922 const ObjCImplicitSetterGetterRefExpr *Ref = 923 cast<ObjCImplicitSetterGetterRefExpr>(this); 924 // FIXME: We really want the location of the '.' here. 925 Loc = Ref->getLocation(); 926 R1 = SourceRange(Ref->getLocation(), Ref->getLocation()); 927 if (Ref->getBase()) 928 R2 = Ref->getBase()->getSourceRange(); 929#else 930 Loc = getExprLoc(); 931 R1 = getSourceRange(); 932#endif 933 return true; 934 } 935 case StmtExprClass: { 936 // Statement exprs don't logically have side effects themselves, but are 937 // sometimes used in macros in ways that give them a type that is unused. 938 // For example ({ blah; foo(); }) will end up with a type if foo has a type. 939 // however, if the result of the stmt expr is dead, we don't want to emit a 940 // warning. 941 const CompoundStmt *CS = cast<StmtExpr>(this)->getSubStmt(); 942 if (!CS->body_empty()) 943 if (const Expr *E = dyn_cast<Expr>(CS->body_back())) 944 return E->isUnusedResultAWarning(Loc, R1, R2, Ctx); 945 946 if (getType()->isVoidType()) 947 return false; 948 Loc = cast<StmtExpr>(this)->getLParenLoc(); 949 R1 = getSourceRange(); 950 return true; 951 } 952 case CStyleCastExprClass: 953 // If this is an explicit cast to void, allow it. People do this when they 954 // think they know what they're doing :). 955 if (getType()->isVoidType()) 956 return false; 957 Loc = cast<CStyleCastExpr>(this)->getLParenLoc(); 958 R1 = cast<CStyleCastExpr>(this)->getSubExpr()->getSourceRange(); 959 return true; 960 case CXXFunctionalCastExprClass: { 961 if (getType()->isVoidType()) 962 return false; 963 const CastExpr *CE = cast<CastExpr>(this); 964 965 // If this is a cast to void or a constructor conversion, check the operand. 966 // Otherwise, the result of the cast is unused. 967 if (CE->getCastKind() == CastExpr::CK_ToVoid || 968 CE->getCastKind() == CastExpr::CK_ConstructorConversion) 969 return (cast<CastExpr>(this)->getSubExpr() 970 ->isUnusedResultAWarning(Loc, R1, R2, Ctx)); 971 Loc = cast<CXXFunctionalCastExpr>(this)->getTypeBeginLoc(); 972 R1 = cast<CXXFunctionalCastExpr>(this)->getSubExpr()->getSourceRange(); 973 return true; 974 } 975 976 case ImplicitCastExprClass: 977 // Check the operand, since implicit casts are inserted by Sema 978 return (cast<ImplicitCastExpr>(this) 979 ->getSubExpr()->isUnusedResultAWarning(Loc, R1, R2, Ctx)); 980 981 case CXXDefaultArgExprClass: 982 return (cast<CXXDefaultArgExpr>(this) 983 ->getExpr()->isUnusedResultAWarning(Loc, R1, R2, Ctx)); 984 985 case CXXNewExprClass: 986 // FIXME: In theory, there might be new expressions that don't have side 987 // effects (e.g. a placement new with an uninitialized POD). 988 case CXXDeleteExprClass: 989 return false; 990 case CXXBindTemporaryExprClass: 991 return (cast<CXXBindTemporaryExpr>(this) 992 ->getSubExpr()->isUnusedResultAWarning(Loc, R1, R2, Ctx)); 993 case CXXExprWithTemporariesClass: 994 return (cast<CXXExprWithTemporaries>(this) 995 ->getSubExpr()->isUnusedResultAWarning(Loc, R1, R2, Ctx)); 996 } 997} 998 999/// DeclCanBeLvalue - Determine whether the given declaration can be 1000/// an lvalue. This is a helper routine for isLvalue. 1001static bool DeclCanBeLvalue(const NamedDecl *Decl, ASTContext &Ctx) { 1002 // C++ [temp.param]p6: 1003 // A non-type non-reference template-parameter is not an lvalue. 1004 if (const NonTypeTemplateParmDecl *NTTParm 1005 = dyn_cast<NonTypeTemplateParmDecl>(Decl)) 1006 return NTTParm->getType()->isReferenceType(); 1007 1008 return isa<VarDecl>(Decl) || isa<FieldDecl>(Decl) || 1009 // C++ 3.10p2: An lvalue refers to an object or function. 1010 (Ctx.getLangOptions().CPlusPlus && 1011 (isa<FunctionDecl>(Decl) || isa<FunctionTemplateDecl>(Decl))); 1012} 1013 1014/// isLvalue - C99 6.3.2.1: an lvalue is an expression with an object type or an 1015/// incomplete type other than void. Nonarray expressions that can be lvalues: 1016/// - name, where name must be a variable 1017/// - e[i] 1018/// - (e), where e must be an lvalue 1019/// - e.name, where e must be an lvalue 1020/// - e->name 1021/// - *e, the type of e cannot be a function type 1022/// - string-constant 1023/// - (__real__ e) and (__imag__ e) where e is an lvalue [GNU extension] 1024/// - reference type [C++ [expr]] 1025/// 1026Expr::isLvalueResult Expr::isLvalue(ASTContext &Ctx) const { 1027 assert(!TR->isReferenceType() && "Expressions can't have reference type."); 1028 1029 isLvalueResult Res = isLvalueInternal(Ctx); 1030 if (Res != LV_Valid || Ctx.getLangOptions().CPlusPlus) 1031 return Res; 1032 1033 // first, check the type (C99 6.3.2.1). Expressions with function 1034 // type in C are not lvalues, but they can be lvalues in C++. 1035 if (TR->isFunctionType() || TR == Ctx.OverloadTy) 1036 return LV_NotObjectType; 1037 1038 // Allow qualified void which is an incomplete type other than void (yuck). 1039 if (TR->isVoidType() && !Ctx.getCanonicalType(TR).hasQualifiers()) 1040 return LV_IncompleteVoidType; 1041 1042 return LV_Valid; 1043} 1044 1045// Check whether the expression can be sanely treated like an l-value 1046Expr::isLvalueResult Expr::isLvalueInternal(ASTContext &Ctx) const { 1047 switch (getStmtClass()) { 1048 case ObjCIsaExprClass: 1049 case StringLiteralClass: // C99 6.5.1p4 1050 case ObjCEncodeExprClass: // @encode behaves like its string in every way. 1051 return LV_Valid; 1052 case ArraySubscriptExprClass: // C99 6.5.3p4 (e1[e2] == (*((e1)+(e2)))) 1053 // For vectors, make sure base is an lvalue (i.e. not a function call). 1054 if (cast<ArraySubscriptExpr>(this)->getBase()->getType()->isVectorType()) 1055 return cast<ArraySubscriptExpr>(this)->getBase()->isLvalue(Ctx); 1056 return LV_Valid; 1057 case DeclRefExprClass: { // C99 6.5.1p2 1058 const NamedDecl *RefdDecl = cast<DeclRefExpr>(this)->getDecl(); 1059 if (DeclCanBeLvalue(RefdDecl, Ctx)) 1060 return LV_Valid; 1061 break; 1062 } 1063 case BlockDeclRefExprClass: { 1064 const BlockDeclRefExpr *BDR = cast<BlockDeclRefExpr>(this); 1065 if (isa<VarDecl>(BDR->getDecl())) 1066 return LV_Valid; 1067 break; 1068 } 1069 case MemberExprClass: { 1070 const MemberExpr *m = cast<MemberExpr>(this); 1071 if (Ctx.getLangOptions().CPlusPlus) { // C++ [expr.ref]p4: 1072 NamedDecl *Member = m->getMemberDecl(); 1073 // C++ [expr.ref]p4: 1074 // If E2 is declared to have type "reference to T", then E1.E2 1075 // is an lvalue. 1076 if (ValueDecl *Value = dyn_cast<ValueDecl>(Member)) 1077 if (Value->getType()->isReferenceType()) 1078 return LV_Valid; 1079 1080 // -- If E2 is a static data member [...] then E1.E2 is an lvalue. 1081 if (isa<VarDecl>(Member) && Member->getDeclContext()->isRecord()) 1082 return LV_Valid; 1083 1084 // -- If E2 is a non-static data member [...]. If E1 is an 1085 // lvalue, then E1.E2 is an lvalue. 1086 if (isa<FieldDecl>(Member)) { 1087 if (m->isArrow()) 1088 return LV_Valid; 1089 return m->getBase()->isLvalue(Ctx); 1090 } 1091 1092 // -- If it refers to a static member function [...], then 1093 // E1.E2 is an lvalue. 1094 // -- Otherwise, if E1.E2 refers to a non-static member 1095 // function [...], then E1.E2 is not an lvalue. 1096 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Member)) 1097 return Method->isStatic()? LV_Valid : LV_MemberFunction; 1098 1099 // -- If E2 is a member enumerator [...], the expression E1.E2 1100 // is not an lvalue. 1101 if (isa<EnumConstantDecl>(Member)) 1102 return LV_InvalidExpression; 1103 1104 // Not an lvalue. 1105 return LV_InvalidExpression; 1106 } 1107 1108 // C99 6.5.2.3p4 1109 if (m->isArrow()) 1110 return LV_Valid; 1111 Expr *BaseExp = m->getBase(); 1112 if (BaseExp->getStmtClass() == ObjCPropertyRefExprClass || 1113 BaseExp->getStmtClass() == ObjCImplicitSetterGetterRefExprClass) 1114 return LV_SubObjCPropertySetting; 1115 return 1116 BaseExp->isLvalue(Ctx); 1117 } 1118 case UnaryOperatorClass: 1119 if (cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::Deref) 1120 return LV_Valid; // C99 6.5.3p4 1121 1122 if (cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::Real || 1123 cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::Imag || 1124 cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::Extension) 1125 return cast<UnaryOperator>(this)->getSubExpr()->isLvalue(Ctx); // GNU. 1126 1127 if (Ctx.getLangOptions().CPlusPlus && // C++ [expr.pre.incr]p1 1128 (cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::PreInc || 1129 cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::PreDec)) 1130 return LV_Valid; 1131 break; 1132 case ImplicitCastExprClass: 1133 if (cast<ImplicitCastExpr>(this)->isLvalueCast()) 1134 return LV_Valid; 1135 1136 // If this is a conversion to a class temporary, make a note of 1137 // that. 1138 if (Ctx.getLangOptions().CPlusPlus && getType()->isRecordType()) 1139 return LV_ClassTemporary; 1140 1141 break; 1142 case ParenExprClass: // C99 6.5.1p5 1143 return cast<ParenExpr>(this)->getSubExpr()->isLvalue(Ctx); 1144 case BinaryOperatorClass: 1145 case CompoundAssignOperatorClass: { 1146 const BinaryOperator *BinOp = cast<BinaryOperator>(this); 1147 1148 if (Ctx.getLangOptions().CPlusPlus && // C++ [expr.comma]p1 1149 BinOp->getOpcode() == BinaryOperator::Comma) 1150 return BinOp->getRHS()->isLvalue(Ctx); 1151 1152 // C++ [expr.mptr.oper]p6 1153 // The result of a .* expression is an lvalue only if its first operand is 1154 // an lvalue and its second operand is a pointer to data member. 1155 if (BinOp->getOpcode() == BinaryOperator::PtrMemD && 1156 !BinOp->getType()->isFunctionType()) 1157 return BinOp->getLHS()->isLvalue(Ctx); 1158 1159 // The result of an ->* expression is an lvalue only if its second operand 1160 // is a pointer to data member. 1161 if (BinOp->getOpcode() == BinaryOperator::PtrMemI && 1162 !BinOp->getType()->isFunctionType()) { 1163 QualType Ty = BinOp->getRHS()->getType(); 1164 if (Ty->isMemberPointerType() && !Ty->isMemberFunctionPointerType()) 1165 return LV_Valid; 1166 } 1167 1168 if (!BinOp->isAssignmentOp()) 1169 return LV_InvalidExpression; 1170 1171 if (Ctx.getLangOptions().CPlusPlus) 1172 // C++ [expr.ass]p1: 1173 // The result of an assignment operation [...] is an lvalue. 1174 return LV_Valid; 1175 1176 1177 // C99 6.5.16: 1178 // An assignment expression [...] is not an lvalue. 1179 return LV_InvalidExpression; 1180 } 1181 case CallExprClass: 1182 case CXXOperatorCallExprClass: 1183 case CXXMemberCallExprClass: { 1184 // C++0x [expr.call]p10 1185 // A function call is an lvalue if and only if the result type 1186 // is an lvalue reference. 1187 QualType ReturnType = cast<CallExpr>(this)->getCallReturnType(); 1188 if (ReturnType->isLValueReferenceType()) 1189 return LV_Valid; 1190 1191 // If the function is returning a class temporary, make a note of 1192 // that. 1193 if (Ctx.getLangOptions().CPlusPlus && ReturnType->isRecordType()) 1194 return LV_ClassTemporary; 1195 1196 break; 1197 } 1198 case CompoundLiteralExprClass: // C99 6.5.2.5p5 1199 // FIXME: Is this what we want in C++? 1200 return LV_Valid; 1201 case ChooseExprClass: 1202 // __builtin_choose_expr is an lvalue if the selected operand is. 1203 return cast<ChooseExpr>(this)->getChosenSubExpr(Ctx)->isLvalue(Ctx); 1204 case ExtVectorElementExprClass: 1205 if (cast<ExtVectorElementExpr>(this)->containsDuplicateElements()) 1206 return LV_DuplicateVectorComponents; 1207 return LV_Valid; 1208 case ObjCIvarRefExprClass: // ObjC instance variables are lvalues. 1209 return LV_Valid; 1210 case ObjCPropertyRefExprClass: // FIXME: check if read-only property. 1211 return LV_Valid; 1212 case ObjCImplicitSetterGetterRefExprClass: // FIXME: check if read-only property. 1213 return LV_Valid; 1214 case PredefinedExprClass: 1215 return LV_Valid; 1216 case UnresolvedLookupExprClass: 1217 return LV_Valid; 1218 case CXXDefaultArgExprClass: 1219 return cast<CXXDefaultArgExpr>(this)->getExpr()->isLvalue(Ctx); 1220 case CStyleCastExprClass: 1221 case CXXFunctionalCastExprClass: 1222 case CXXStaticCastExprClass: 1223 case CXXDynamicCastExprClass: 1224 case CXXReinterpretCastExprClass: 1225 case CXXConstCastExprClass: 1226 // The result of an explicit cast is an lvalue if the type we are 1227 // casting to is an lvalue reference type. See C++ [expr.cast]p1, 1228 // C++ [expr.static.cast]p2, C++ [expr.dynamic.cast]p2, 1229 // C++ [expr.reinterpret.cast]p1, C++ [expr.const.cast]p1. 1230 if (cast<ExplicitCastExpr>(this)->getTypeAsWritten()-> 1231 isLValueReferenceType()) 1232 return LV_Valid; 1233 1234 // If this is a conversion to a class temporary, make a note of 1235 // that. 1236 if (Ctx.getLangOptions().CPlusPlus && 1237 cast<ExplicitCastExpr>(this)->getTypeAsWritten()->isRecordType()) 1238 return LV_ClassTemporary; 1239 1240 break; 1241 case CXXTypeidExprClass: 1242 // C++ 5.2.8p1: The result of a typeid expression is an lvalue of ... 1243 return LV_Valid; 1244 case CXXBindTemporaryExprClass: 1245 return cast<CXXBindTemporaryExpr>(this)->getSubExpr()-> 1246 isLvalueInternal(Ctx); 1247 case CXXBindReferenceExprClass: 1248 // Something that's bound to a reference is always an lvalue. 1249 return LV_Valid; 1250 case ConditionalOperatorClass: { 1251 // Complicated handling is only for C++. 1252 if (!Ctx.getLangOptions().CPlusPlus) 1253 return LV_InvalidExpression; 1254 1255 // Sema should have taken care to ensure that a CXXTemporaryObjectExpr is 1256 // everywhere there's an object converted to an rvalue. Also, any other 1257 // casts should be wrapped by ImplicitCastExprs. There's just the special 1258 // case involving throws to work out. 1259 const ConditionalOperator *Cond = cast<ConditionalOperator>(this); 1260 Expr *True = Cond->getTrueExpr(); 1261 Expr *False = Cond->getFalseExpr(); 1262 // C++0x 5.16p2 1263 // If either the second or the third operand has type (cv) void, [...] 1264 // the result [...] is an rvalue. 1265 if (True->getType()->isVoidType() || False->getType()->isVoidType()) 1266 return LV_InvalidExpression; 1267 1268 // Both sides must be lvalues for the result to be an lvalue. 1269 if (True->isLvalue(Ctx) != LV_Valid || False->isLvalue(Ctx) != LV_Valid) 1270 return LV_InvalidExpression; 1271 1272 // That's it. 1273 return LV_Valid; 1274 } 1275 1276 case Expr::CXXExprWithTemporariesClass: 1277 return cast<CXXExprWithTemporaries>(this)->getSubExpr()->isLvalue(Ctx); 1278 1279 case Expr::ObjCMessageExprClass: 1280 if (const ObjCMethodDecl *Method 1281 = cast<ObjCMessageExpr>(this)->getMethodDecl()) 1282 if (Method->getResultType()->isLValueReferenceType()) 1283 return LV_Valid; 1284 break; 1285 1286 case Expr::CXXConstructExprClass: 1287 case Expr::CXXTemporaryObjectExprClass: 1288 case Expr::CXXZeroInitValueExprClass: 1289 return LV_ClassTemporary; 1290 1291 default: 1292 break; 1293 } 1294 return LV_InvalidExpression; 1295} 1296 1297/// isModifiableLvalue - C99 6.3.2.1: an lvalue that does not have array type, 1298/// does not have an incomplete type, does not have a const-qualified type, and 1299/// if it is a structure or union, does not have any member (including, 1300/// recursively, any member or element of all contained aggregates or unions) 1301/// with a const-qualified type. 1302Expr::isModifiableLvalueResult 1303Expr::isModifiableLvalue(ASTContext &Ctx, SourceLocation *Loc) const { 1304 isLvalueResult lvalResult = isLvalue(Ctx); 1305 1306 switch (lvalResult) { 1307 case LV_Valid: 1308 // C++ 3.10p11: Functions cannot be modified, but pointers to 1309 // functions can be modifiable. 1310 if (Ctx.getLangOptions().CPlusPlus && TR->isFunctionType()) 1311 return MLV_NotObjectType; 1312 break; 1313 1314 case LV_NotObjectType: return MLV_NotObjectType; 1315 case LV_IncompleteVoidType: return MLV_IncompleteVoidType; 1316 case LV_DuplicateVectorComponents: return MLV_DuplicateVectorComponents; 1317 case LV_InvalidExpression: 1318 // If the top level is a C-style cast, and the subexpression is a valid 1319 // lvalue, then this is probably a use of the old-school "cast as lvalue" 1320 // GCC extension. We don't support it, but we want to produce good 1321 // diagnostics when it happens so that the user knows why. 1322 if (const CStyleCastExpr *CE = dyn_cast<CStyleCastExpr>(IgnoreParens())) { 1323 if (CE->getSubExpr()->isLvalue(Ctx) == LV_Valid) { 1324 if (Loc) 1325 *Loc = CE->getLParenLoc(); 1326 return MLV_LValueCast; 1327 } 1328 } 1329 return MLV_InvalidExpression; 1330 case LV_MemberFunction: return MLV_MemberFunction; 1331 case LV_SubObjCPropertySetting: return MLV_SubObjCPropertySetting; 1332 case LV_ClassTemporary: 1333 return MLV_ClassTemporary; 1334 } 1335 1336 // The following is illegal: 1337 // void takeclosure(void (^C)(void)); 1338 // void func() { int x = 1; takeclosure(^{ x = 7; }); } 1339 // 1340 if (const BlockDeclRefExpr *BDR = dyn_cast<BlockDeclRefExpr>(this)) { 1341 if (!BDR->isByRef() && isa<VarDecl>(BDR->getDecl())) 1342 return MLV_NotBlockQualified; 1343 } 1344 1345 // Assigning to an 'implicit' property? 1346 if (const ObjCImplicitSetterGetterRefExpr* Expr = 1347 dyn_cast<ObjCImplicitSetterGetterRefExpr>(this)) { 1348 if (Expr->getSetterMethod() == 0) 1349 return MLV_NoSetterProperty; 1350 } 1351 1352 QualType CT = Ctx.getCanonicalType(getType()); 1353 1354 if (CT.isConstQualified()) 1355 return MLV_ConstQualified; 1356 if (CT->isArrayType()) 1357 return MLV_ArrayType; 1358 if (CT->isIncompleteType()) 1359 return MLV_IncompleteType; 1360 1361 if (const RecordType *r = CT->getAs<RecordType>()) { 1362 if (r->hasConstFields()) 1363 return MLV_ConstQualified; 1364 } 1365 1366 return MLV_Valid; 1367} 1368 1369/// isOBJCGCCandidate - Check if an expression is objc gc'able. 1370/// returns true, if it is; false otherwise. 1371bool Expr::isOBJCGCCandidate(ASTContext &Ctx) const { 1372 switch (getStmtClass()) { 1373 default: 1374 return false; 1375 case ObjCIvarRefExprClass: 1376 return true; 1377 case Expr::UnaryOperatorClass: 1378 return cast<UnaryOperator>(this)->getSubExpr()->isOBJCGCCandidate(Ctx); 1379 case ParenExprClass: 1380 return cast<ParenExpr>(this)->getSubExpr()->isOBJCGCCandidate(Ctx); 1381 case ImplicitCastExprClass: 1382 return cast<ImplicitCastExpr>(this)->getSubExpr()->isOBJCGCCandidate(Ctx); 1383 case CStyleCastExprClass: 1384 return cast<CStyleCastExpr>(this)->getSubExpr()->isOBJCGCCandidate(Ctx); 1385 case DeclRefExprClass: { 1386 const Decl *D = cast<DeclRefExpr>(this)->getDecl(); 1387 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1388 if (VD->hasGlobalStorage()) 1389 return true; 1390 QualType T = VD->getType(); 1391 // dereferencing to a pointer is always a gc'able candidate, 1392 // unless it is __weak. 1393 return T->isPointerType() && 1394 (Ctx.getObjCGCAttrKind(T) != Qualifiers::Weak); 1395 } 1396 return false; 1397 } 1398 case MemberExprClass: { 1399 const MemberExpr *M = cast<MemberExpr>(this); 1400 return M->getBase()->isOBJCGCCandidate(Ctx); 1401 } 1402 case ArraySubscriptExprClass: 1403 return cast<ArraySubscriptExpr>(this)->getBase()->isOBJCGCCandidate(Ctx); 1404 } 1405} 1406Expr* Expr::IgnoreParens() { 1407 Expr* E = this; 1408 while (ParenExpr* P = dyn_cast<ParenExpr>(E)) 1409 E = P->getSubExpr(); 1410 1411 return E; 1412} 1413 1414/// IgnoreParenCasts - Ignore parentheses and casts. Strip off any ParenExpr 1415/// or CastExprs or ImplicitCastExprs, returning their operand. 1416Expr *Expr::IgnoreParenCasts() { 1417 Expr *E = this; 1418 while (true) { 1419 if (ParenExpr *P = dyn_cast<ParenExpr>(E)) 1420 E = P->getSubExpr(); 1421 else if (CastExpr *P = dyn_cast<CastExpr>(E)) 1422 E = P->getSubExpr(); 1423 else 1424 return E; 1425 } 1426} 1427 1428/// IgnoreParenNoopCasts - Ignore parentheses and casts that do not change the 1429/// value (including ptr->int casts of the same size). Strip off any 1430/// ParenExpr or CastExprs, returning their operand. 1431Expr *Expr::IgnoreParenNoopCasts(ASTContext &Ctx) { 1432 Expr *E = this; 1433 while (true) { 1434 if (ParenExpr *P = dyn_cast<ParenExpr>(E)) { 1435 E = P->getSubExpr(); 1436 continue; 1437 } 1438 1439 if (CastExpr *P = dyn_cast<CastExpr>(E)) { 1440 // We ignore integer <-> casts that are of the same width, ptr<->ptr and 1441 // ptr<->int casts of the same width. We also ignore all identify casts. 1442 Expr *SE = P->getSubExpr(); 1443 1444 if (Ctx.hasSameUnqualifiedType(E->getType(), SE->getType())) { 1445 E = SE; 1446 continue; 1447 } 1448 1449 if ((E->getType()->isPointerType() || E->getType()->isIntegralType()) && 1450 (SE->getType()->isPointerType() || SE->getType()->isIntegralType()) && 1451 Ctx.getTypeSize(E->getType()) == Ctx.getTypeSize(SE->getType())) { 1452 E = SE; 1453 continue; 1454 } 1455 } 1456 1457 return E; 1458 } 1459} 1460 1461bool Expr::isDefaultArgument() const { 1462 const Expr *E = this; 1463 while (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) 1464 E = ICE->getSubExprAsWritten(); 1465 1466 return isa<CXXDefaultArgExpr>(E); 1467} 1468 1469/// hasAnyTypeDependentArguments - Determines if any of the expressions 1470/// in Exprs is type-dependent. 1471bool Expr::hasAnyTypeDependentArguments(Expr** Exprs, unsigned NumExprs) { 1472 for (unsigned I = 0; I < NumExprs; ++I) 1473 if (Exprs[I]->isTypeDependent()) 1474 return true; 1475 1476 return false; 1477} 1478 1479/// hasAnyValueDependentArguments - Determines if any of the expressions 1480/// in Exprs is value-dependent. 1481bool Expr::hasAnyValueDependentArguments(Expr** Exprs, unsigned NumExprs) { 1482 for (unsigned I = 0; I < NumExprs; ++I) 1483 if (Exprs[I]->isValueDependent()) 1484 return true; 1485 1486 return false; 1487} 1488 1489bool Expr::isConstantInitializer(ASTContext &Ctx) const { 1490 // This function is attempting whether an expression is an initializer 1491 // which can be evaluated at compile-time. isEvaluatable handles most 1492 // of the cases, but it can't deal with some initializer-specific 1493 // expressions, and it can't deal with aggregates; we deal with those here, 1494 // and fall back to isEvaluatable for the other cases. 1495 1496 // FIXME: This function assumes the variable being assigned to 1497 // isn't a reference type! 1498 1499 switch (getStmtClass()) { 1500 default: break; 1501 case StringLiteralClass: 1502 case ObjCStringLiteralClass: 1503 case ObjCEncodeExprClass: 1504 return true; 1505 case CompoundLiteralExprClass: { 1506 // This handles gcc's extension that allows global initializers like 1507 // "struct x {int x;} x = (struct x) {};". 1508 // FIXME: This accepts other cases it shouldn't! 1509 const Expr *Exp = cast<CompoundLiteralExpr>(this)->getInitializer(); 1510 return Exp->isConstantInitializer(Ctx); 1511 } 1512 case InitListExprClass: { 1513 // FIXME: This doesn't deal with fields with reference types correctly. 1514 // FIXME: This incorrectly allows pointers cast to integers to be assigned 1515 // to bitfields. 1516 const InitListExpr *Exp = cast<InitListExpr>(this); 1517 unsigned numInits = Exp->getNumInits(); 1518 for (unsigned i = 0; i < numInits; i++) { 1519 if (!Exp->getInit(i)->isConstantInitializer(Ctx)) 1520 return false; 1521 } 1522 return true; 1523 } 1524 case ImplicitValueInitExprClass: 1525 return true; 1526 case ParenExprClass: 1527 return cast<ParenExpr>(this)->getSubExpr()->isConstantInitializer(Ctx); 1528 case UnaryOperatorClass: { 1529 const UnaryOperator* Exp = cast<UnaryOperator>(this); 1530 if (Exp->getOpcode() == UnaryOperator::Extension) 1531 return Exp->getSubExpr()->isConstantInitializer(Ctx); 1532 break; 1533 } 1534 case BinaryOperatorClass: { 1535 // Special case &&foo - &&bar. It would be nice to generalize this somehow 1536 // but this handles the common case. 1537 const BinaryOperator *Exp = cast<BinaryOperator>(this); 1538 if (Exp->getOpcode() == BinaryOperator::Sub && 1539 isa<AddrLabelExpr>(Exp->getLHS()->IgnoreParenNoopCasts(Ctx)) && 1540 isa<AddrLabelExpr>(Exp->getRHS()->IgnoreParenNoopCasts(Ctx))) 1541 return true; 1542 break; 1543 } 1544 case ImplicitCastExprClass: 1545 case CStyleCastExprClass: 1546 // Handle casts with a destination that's a struct or union; this 1547 // deals with both the gcc no-op struct cast extension and the 1548 // cast-to-union extension. 1549 if (getType()->isRecordType()) 1550 return cast<CastExpr>(this)->getSubExpr()->isConstantInitializer(Ctx); 1551 1552 // Integer->integer casts can be handled here, which is important for 1553 // things like (int)(&&x-&&y). Scary but true. 1554 if (getType()->isIntegerType() && 1555 cast<CastExpr>(this)->getSubExpr()->getType()->isIntegerType()) 1556 return cast<CastExpr>(this)->getSubExpr()->isConstantInitializer(Ctx); 1557 1558 break; 1559 } 1560 return isEvaluatable(Ctx); 1561} 1562 1563/// isIntegerConstantExpr - this recursive routine will test if an expression is 1564/// an integer constant expression. 1565 1566/// FIXME: Pass up a reason why! Invalid operation in i-c-e, division by zero, 1567/// comma, etc 1568/// 1569/// FIXME: Handle offsetof. Two things to do: Handle GCC's __builtin_offsetof 1570/// to support gcc 4.0+ and handle the idiom GCC recognizes with a null pointer 1571/// cast+dereference. 1572 1573// CheckICE - This function does the fundamental ICE checking: the returned 1574// ICEDiag contains a Val of 0, 1, or 2, and a possibly null SourceLocation. 1575// Note that to reduce code duplication, this helper does no evaluation 1576// itself; the caller checks whether the expression is evaluatable, and 1577// in the rare cases where CheckICE actually cares about the evaluated 1578// value, it calls into Evalute. 1579// 1580// Meanings of Val: 1581// 0: This expression is an ICE if it can be evaluated by Evaluate. 1582// 1: This expression is not an ICE, but if it isn't evaluated, it's 1583// a legal subexpression for an ICE. This return value is used to handle 1584// the comma operator in C99 mode. 1585// 2: This expression is not an ICE, and is not a legal subexpression for one. 1586 1587struct ICEDiag { 1588 unsigned Val; 1589 SourceLocation Loc; 1590 1591 public: 1592 ICEDiag(unsigned v, SourceLocation l) : Val(v), Loc(l) {} 1593 ICEDiag() : Val(0) {} 1594}; 1595 1596ICEDiag NoDiag() { return ICEDiag(); } 1597 1598static ICEDiag CheckEvalInICE(const Expr* E, ASTContext &Ctx) { 1599 Expr::EvalResult EVResult; 1600 if (!E->Evaluate(EVResult, Ctx) || EVResult.HasSideEffects || 1601 !EVResult.Val.isInt()) { 1602 return ICEDiag(2, E->getLocStart()); 1603 } 1604 return NoDiag(); 1605} 1606 1607static ICEDiag CheckICE(const Expr* E, ASTContext &Ctx) { 1608 assert(!E->isValueDependent() && "Should not see value dependent exprs!"); 1609 if (!E->getType()->isIntegralType()) { 1610 return ICEDiag(2, E->getLocStart()); 1611 } 1612 1613 switch (E->getStmtClass()) { 1614#define STMT(Node, Base) case Expr::Node##Class: 1615#define EXPR(Node, Base) 1616#include "clang/AST/StmtNodes.def" 1617 case Expr::PredefinedExprClass: 1618 case Expr::FloatingLiteralClass: 1619 case Expr::ImaginaryLiteralClass: 1620 case Expr::StringLiteralClass: 1621 case Expr::ArraySubscriptExprClass: 1622 case Expr::MemberExprClass: 1623 case Expr::CompoundAssignOperatorClass: 1624 case Expr::CompoundLiteralExprClass: 1625 case Expr::ExtVectorElementExprClass: 1626 case Expr::InitListExprClass: 1627 case Expr::DesignatedInitExprClass: 1628 case Expr::ImplicitValueInitExprClass: 1629 case Expr::ParenListExprClass: 1630 case Expr::VAArgExprClass: 1631 case Expr::AddrLabelExprClass: 1632 case Expr::StmtExprClass: 1633 case Expr::CXXMemberCallExprClass: 1634 case Expr::CXXDynamicCastExprClass: 1635 case Expr::CXXTypeidExprClass: 1636 case Expr::CXXNullPtrLiteralExprClass: 1637 case Expr::CXXThisExprClass: 1638 case Expr::CXXThrowExprClass: 1639 case Expr::CXXNewExprClass: 1640 case Expr::CXXDeleteExprClass: 1641 case Expr::CXXPseudoDestructorExprClass: 1642 case Expr::UnresolvedLookupExprClass: 1643 case Expr::DependentScopeDeclRefExprClass: 1644 case Expr::CXXConstructExprClass: 1645 case Expr::CXXBindTemporaryExprClass: 1646 case Expr::CXXBindReferenceExprClass: 1647 case Expr::CXXExprWithTemporariesClass: 1648 case Expr::CXXTemporaryObjectExprClass: 1649 case Expr::CXXUnresolvedConstructExprClass: 1650 case Expr::CXXDependentScopeMemberExprClass: 1651 case Expr::UnresolvedMemberExprClass: 1652 case Expr::ObjCStringLiteralClass: 1653 case Expr::ObjCEncodeExprClass: 1654 case Expr::ObjCMessageExprClass: 1655 case Expr::ObjCSelectorExprClass: 1656 case Expr::ObjCProtocolExprClass: 1657 case Expr::ObjCIvarRefExprClass: 1658 case Expr::ObjCPropertyRefExprClass: 1659 case Expr::ObjCImplicitSetterGetterRefExprClass: 1660 case Expr::ObjCSuperExprClass: 1661 case Expr::ObjCIsaExprClass: 1662 case Expr::ShuffleVectorExprClass: 1663 case Expr::BlockExprClass: 1664 case Expr::BlockDeclRefExprClass: 1665 case Expr::NoStmtClass: 1666 return ICEDiag(2, E->getLocStart()); 1667 1668 case Expr::GNUNullExprClass: 1669 // GCC considers the GNU __null value to be an integral constant expression. 1670 return NoDiag(); 1671 1672 case Expr::ParenExprClass: 1673 return CheckICE(cast<ParenExpr>(E)->getSubExpr(), Ctx); 1674 case Expr::IntegerLiteralClass: 1675 case Expr::CharacterLiteralClass: 1676 case Expr::CXXBoolLiteralExprClass: 1677 case Expr::CXXZeroInitValueExprClass: 1678 case Expr::TypesCompatibleExprClass: 1679 case Expr::UnaryTypeTraitExprClass: 1680 return NoDiag(); 1681 case Expr::CallExprClass: 1682 case Expr::CXXOperatorCallExprClass: { 1683 const CallExpr *CE = cast<CallExpr>(E); 1684 if (CE->isBuiltinCall(Ctx)) 1685 return CheckEvalInICE(E, Ctx); 1686 return ICEDiag(2, E->getLocStart()); 1687 } 1688 case Expr::DeclRefExprClass: 1689 if (isa<EnumConstantDecl>(cast<DeclRefExpr>(E)->getDecl())) 1690 return NoDiag(); 1691 if (Ctx.getLangOptions().CPlusPlus && 1692 E->getType().getCVRQualifiers() == Qualifiers::Const) { 1693 const NamedDecl *D = cast<DeclRefExpr>(E)->getDecl(); 1694 1695 // Parameter variables are never constants. Without this check, 1696 // getAnyInitializer() can find a default argument, which leads 1697 // to chaos. 1698 if (isa<ParmVarDecl>(D)) 1699 return ICEDiag(2, cast<DeclRefExpr>(E)->getLocation()); 1700 1701 // C++ 7.1.5.1p2 1702 // A variable of non-volatile const-qualified integral or enumeration 1703 // type initialized by an ICE can be used in ICEs. 1704 if (const VarDecl *Dcl = dyn_cast<VarDecl>(D)) { 1705 Qualifiers Quals = Ctx.getCanonicalType(Dcl->getType()).getQualifiers(); 1706 if (Quals.hasVolatile() || !Quals.hasConst()) 1707 return ICEDiag(2, cast<DeclRefExpr>(E)->getLocation()); 1708 1709 // Look for a declaration of this variable that has an initializer. 1710 const VarDecl *ID = 0; 1711 const Expr *Init = Dcl->getAnyInitializer(ID); 1712 if (Init) { 1713 if (ID->isInitKnownICE()) { 1714 // We have already checked whether this subexpression is an 1715 // integral constant expression. 1716 if (ID->isInitICE()) 1717 return NoDiag(); 1718 else 1719 return ICEDiag(2, cast<DeclRefExpr>(E)->getLocation()); 1720 } 1721 1722 // It's an ICE whether or not the definition we found is 1723 // out-of-line. See DR 721 and the discussion in Clang PR 1724 // 6206 for details. 1725 1726 if (Dcl->isCheckingICE()) { 1727 return ICEDiag(2, cast<DeclRefExpr>(E)->getLocation()); 1728 } 1729 1730 Dcl->setCheckingICE(); 1731 ICEDiag Result = CheckICE(Init, Ctx); 1732 // Cache the result of the ICE test. 1733 Dcl->setInitKnownICE(Result.Val == 0); 1734 return Result; 1735 } 1736 } 1737 } 1738 return ICEDiag(2, E->getLocStart()); 1739 case Expr::UnaryOperatorClass: { 1740 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1741 switch (Exp->getOpcode()) { 1742 case UnaryOperator::PostInc: 1743 case UnaryOperator::PostDec: 1744 case UnaryOperator::PreInc: 1745 case UnaryOperator::PreDec: 1746 case UnaryOperator::AddrOf: 1747 case UnaryOperator::Deref: 1748 return ICEDiag(2, E->getLocStart()); 1749 1750 case UnaryOperator::Extension: 1751 case UnaryOperator::LNot: 1752 case UnaryOperator::Plus: 1753 case UnaryOperator::Minus: 1754 case UnaryOperator::Not: 1755 case UnaryOperator::Real: 1756 case UnaryOperator::Imag: 1757 return CheckICE(Exp->getSubExpr(), Ctx); 1758 case UnaryOperator::OffsetOf: 1759 // Note that per C99, offsetof must be an ICE. And AFAIK, using 1760 // Evaluate matches the proposed gcc behavior for cases like 1761 // "offsetof(struct s{int x[4];}, x[!.0])". This doesn't affect 1762 // compliance: we should warn earlier for offsetof expressions with 1763 // array subscripts that aren't ICEs, and if the array subscripts 1764 // are ICEs, the value of the offsetof must be an integer constant. 1765 return CheckEvalInICE(E, Ctx); 1766 } 1767 } 1768 case Expr::SizeOfAlignOfExprClass: { 1769 const SizeOfAlignOfExpr *Exp = cast<SizeOfAlignOfExpr>(E); 1770 if (Exp->isSizeOf() && Exp->getTypeOfArgument()->isVariableArrayType()) 1771 return ICEDiag(2, E->getLocStart()); 1772 return NoDiag(); 1773 } 1774 case Expr::BinaryOperatorClass: { 1775 const BinaryOperator *Exp = cast<BinaryOperator>(E); 1776 switch (Exp->getOpcode()) { 1777 case BinaryOperator::PtrMemD: 1778 case BinaryOperator::PtrMemI: 1779 case BinaryOperator::Assign: 1780 case BinaryOperator::MulAssign: 1781 case BinaryOperator::DivAssign: 1782 case BinaryOperator::RemAssign: 1783 case BinaryOperator::AddAssign: 1784 case BinaryOperator::SubAssign: 1785 case BinaryOperator::ShlAssign: 1786 case BinaryOperator::ShrAssign: 1787 case BinaryOperator::AndAssign: 1788 case BinaryOperator::XorAssign: 1789 case BinaryOperator::OrAssign: 1790 return ICEDiag(2, E->getLocStart()); 1791 1792 case BinaryOperator::Mul: 1793 case BinaryOperator::Div: 1794 case BinaryOperator::Rem: 1795 case BinaryOperator::Add: 1796 case BinaryOperator::Sub: 1797 case BinaryOperator::Shl: 1798 case BinaryOperator::Shr: 1799 case BinaryOperator::LT: 1800 case BinaryOperator::GT: 1801 case BinaryOperator::LE: 1802 case BinaryOperator::GE: 1803 case BinaryOperator::EQ: 1804 case BinaryOperator::NE: 1805 case BinaryOperator::And: 1806 case BinaryOperator::Xor: 1807 case BinaryOperator::Or: 1808 case BinaryOperator::Comma: { 1809 ICEDiag LHSResult = CheckICE(Exp->getLHS(), Ctx); 1810 ICEDiag RHSResult = CheckICE(Exp->getRHS(), Ctx); 1811 if (Exp->getOpcode() == BinaryOperator::Div || 1812 Exp->getOpcode() == BinaryOperator::Rem) { 1813 // Evaluate gives an error for undefined Div/Rem, so make sure 1814 // we don't evaluate one. 1815 if (LHSResult.Val != 2 && RHSResult.Val != 2) { 1816 llvm::APSInt REval = Exp->getRHS()->EvaluateAsInt(Ctx); 1817 if (REval == 0) 1818 return ICEDiag(1, E->getLocStart()); 1819 if (REval.isSigned() && REval.isAllOnesValue()) { 1820 llvm::APSInt LEval = Exp->getLHS()->EvaluateAsInt(Ctx); 1821 if (LEval.isMinSignedValue()) 1822 return ICEDiag(1, E->getLocStart()); 1823 } 1824 } 1825 } 1826 if (Exp->getOpcode() == BinaryOperator::Comma) { 1827 if (Ctx.getLangOptions().C99) { 1828 // C99 6.6p3 introduces a strange edge case: comma can be in an ICE 1829 // if it isn't evaluated. 1830 if (LHSResult.Val == 0 && RHSResult.Val == 0) 1831 return ICEDiag(1, E->getLocStart()); 1832 } else { 1833 // In both C89 and C++, commas in ICEs are illegal. 1834 return ICEDiag(2, E->getLocStart()); 1835 } 1836 } 1837 if (LHSResult.Val >= RHSResult.Val) 1838 return LHSResult; 1839 return RHSResult; 1840 } 1841 case BinaryOperator::LAnd: 1842 case BinaryOperator::LOr: { 1843 ICEDiag LHSResult = CheckICE(Exp->getLHS(), Ctx); 1844 ICEDiag RHSResult = CheckICE(Exp->getRHS(), Ctx); 1845 if (LHSResult.Val == 0 && RHSResult.Val == 1) { 1846 // Rare case where the RHS has a comma "side-effect"; we need 1847 // to actually check the condition to see whether the side 1848 // with the comma is evaluated. 1849 if ((Exp->getOpcode() == BinaryOperator::LAnd) != 1850 (Exp->getLHS()->EvaluateAsInt(Ctx) == 0)) 1851 return RHSResult; 1852 return NoDiag(); 1853 } 1854 1855 if (LHSResult.Val >= RHSResult.Val) 1856 return LHSResult; 1857 return RHSResult; 1858 } 1859 } 1860 } 1861 case Expr::ImplicitCastExprClass: 1862 case Expr::CStyleCastExprClass: 1863 case Expr::CXXFunctionalCastExprClass: 1864 case Expr::CXXNamedCastExprClass: 1865 case Expr::CXXStaticCastExprClass: 1866 case Expr::CXXReinterpretCastExprClass: 1867 case Expr::CXXConstCastExprClass: { 1868 const Expr *SubExpr = cast<CastExpr>(E)->getSubExpr(); 1869 if (SubExpr->getType()->isIntegralType()) 1870 return CheckICE(SubExpr, Ctx); 1871 if (isa<FloatingLiteral>(SubExpr->IgnoreParens())) 1872 return NoDiag(); 1873 return ICEDiag(2, E->getLocStart()); 1874 } 1875 case Expr::ConditionalOperatorClass: { 1876 const ConditionalOperator *Exp = cast<ConditionalOperator>(E); 1877 // If the condition (ignoring parens) is a __builtin_constant_p call, 1878 // then only the true side is actually considered in an integer constant 1879 // expression, and it is fully evaluated. This is an important GNU 1880 // extension. See GCC PR38377 for discussion. 1881 if (const CallExpr *CallCE = dyn_cast<CallExpr>(Exp->getCond()->IgnoreParenCasts())) 1882 if (CallCE->isBuiltinCall(Ctx) == Builtin::BI__builtin_constant_p) { 1883 Expr::EvalResult EVResult; 1884 if (!E->Evaluate(EVResult, Ctx) || EVResult.HasSideEffects || 1885 !EVResult.Val.isInt()) { 1886 return ICEDiag(2, E->getLocStart()); 1887 } 1888 return NoDiag(); 1889 } 1890 ICEDiag CondResult = CheckICE(Exp->getCond(), Ctx); 1891 ICEDiag TrueResult = CheckICE(Exp->getTrueExpr(), Ctx); 1892 ICEDiag FalseResult = CheckICE(Exp->getFalseExpr(), Ctx); 1893 if (CondResult.Val == 2) 1894 return CondResult; 1895 if (TrueResult.Val == 2) 1896 return TrueResult; 1897 if (FalseResult.Val == 2) 1898 return FalseResult; 1899 if (CondResult.Val == 1) 1900 return CondResult; 1901 if (TrueResult.Val == 0 && FalseResult.Val == 0) 1902 return NoDiag(); 1903 // Rare case where the diagnostics depend on which side is evaluated 1904 // Note that if we get here, CondResult is 0, and at least one of 1905 // TrueResult and FalseResult is non-zero. 1906 if (Exp->getCond()->EvaluateAsInt(Ctx) == 0) { 1907 return FalseResult; 1908 } 1909 return TrueResult; 1910 } 1911 case Expr::CXXDefaultArgExprClass: 1912 return CheckICE(cast<CXXDefaultArgExpr>(E)->getExpr(), Ctx); 1913 case Expr::ChooseExprClass: { 1914 return CheckICE(cast<ChooseExpr>(E)->getChosenSubExpr(Ctx), Ctx); 1915 } 1916 } 1917 1918 // Silence a GCC warning 1919 return ICEDiag(2, E->getLocStart()); 1920} 1921 1922bool Expr::isIntegerConstantExpr(llvm::APSInt &Result, ASTContext &Ctx, 1923 SourceLocation *Loc, bool isEvaluated) const { 1924 ICEDiag d = CheckICE(this, Ctx); 1925 if (d.Val != 0) { 1926 if (Loc) *Loc = d.Loc; 1927 return false; 1928 } 1929 EvalResult EvalResult; 1930 if (!Evaluate(EvalResult, Ctx)) 1931 llvm_unreachable("ICE cannot be evaluated!"); 1932 assert(!EvalResult.HasSideEffects && "ICE with side effects!"); 1933 assert(EvalResult.Val.isInt() && "ICE that isn't integer!"); 1934 Result = EvalResult.Val.getInt(); 1935 return true; 1936} 1937 1938/// isNullPointerConstant - C99 6.3.2.3p3 - Return true if this is either an 1939/// integer constant expression with the value zero, or if this is one that is 1940/// cast to void*. 1941bool Expr::isNullPointerConstant(ASTContext &Ctx, 1942 NullPointerConstantValueDependence NPC) const { 1943 if (isValueDependent()) { 1944 switch (NPC) { 1945 case NPC_NeverValueDependent: 1946 assert(false && "Unexpected value dependent expression!"); 1947 // If the unthinkable happens, fall through to the safest alternative. 1948 1949 case NPC_ValueDependentIsNull: 1950 return isTypeDependent() || getType()->isIntegralType(); 1951 1952 case NPC_ValueDependentIsNotNull: 1953 return false; 1954 } 1955 } 1956 1957 // Strip off a cast to void*, if it exists. Except in C++. 1958 if (const ExplicitCastExpr *CE = dyn_cast<ExplicitCastExpr>(this)) { 1959 if (!Ctx.getLangOptions().CPlusPlus) { 1960 // Check that it is a cast to void*. 1961 if (const PointerType *PT = CE->getType()->getAs<PointerType>()) { 1962 QualType Pointee = PT->getPointeeType(); 1963 if (!Pointee.hasQualifiers() && 1964 Pointee->isVoidType() && // to void* 1965 CE->getSubExpr()->getType()->isIntegerType()) // from int. 1966 return CE->getSubExpr()->isNullPointerConstant(Ctx, NPC); 1967 } 1968 } 1969 } else if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(this)) { 1970 // Ignore the ImplicitCastExpr type entirely. 1971 return ICE->getSubExpr()->isNullPointerConstant(Ctx, NPC); 1972 } else if (const ParenExpr *PE = dyn_cast<ParenExpr>(this)) { 1973 // Accept ((void*)0) as a null pointer constant, as many other 1974 // implementations do. 1975 return PE->getSubExpr()->isNullPointerConstant(Ctx, NPC); 1976 } else if (const CXXDefaultArgExpr *DefaultArg 1977 = dyn_cast<CXXDefaultArgExpr>(this)) { 1978 // See through default argument expressions 1979 return DefaultArg->getExpr()->isNullPointerConstant(Ctx, NPC); 1980 } else if (isa<GNUNullExpr>(this)) { 1981 // The GNU __null extension is always a null pointer constant. 1982 return true; 1983 } 1984 1985 // C++0x nullptr_t is always a null pointer constant. 1986 if (getType()->isNullPtrType()) 1987 return true; 1988 1989 // This expression must be an integer type. 1990 if (!getType()->isIntegerType() || 1991 (Ctx.getLangOptions().CPlusPlus && getType()->isEnumeralType())) 1992 return false; 1993 1994 // If we have an integer constant expression, we need to *evaluate* it and 1995 // test for the value 0. 1996 llvm::APSInt Result; 1997 return isIntegerConstantExpr(Result, Ctx) && Result == 0; 1998} 1999 2000FieldDecl *Expr::getBitField() { 2001 Expr *E = this->IgnoreParens(); 2002 2003 while (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) { 2004 if (ICE->isLvalueCast() && ICE->getCastKind() == CastExpr::CK_NoOp) 2005 E = ICE->getSubExpr()->IgnoreParens(); 2006 else 2007 break; 2008 } 2009 2010 if (MemberExpr *MemRef = dyn_cast<MemberExpr>(E)) 2011 if (FieldDecl *Field = dyn_cast<FieldDecl>(MemRef->getMemberDecl())) 2012 if (Field->isBitField()) 2013 return Field; 2014 2015 if (BinaryOperator *BinOp = dyn_cast<BinaryOperator>(E)) 2016 if (BinOp->isAssignmentOp() && BinOp->getLHS()) 2017 return BinOp->getLHS()->getBitField(); 2018 2019 return 0; 2020} 2021 2022bool Expr::refersToVectorElement() const { 2023 const Expr *E = this->IgnoreParens(); 2024 2025 while (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) { 2026 if (ICE->isLvalueCast() && ICE->getCastKind() == CastExpr::CK_NoOp) 2027 E = ICE->getSubExpr()->IgnoreParens(); 2028 else 2029 break; 2030 } 2031 2032 if (const ArraySubscriptExpr *ASE = dyn_cast<ArraySubscriptExpr>(E)) 2033 return ASE->getBase()->getType()->isVectorType(); 2034 2035 if (isa<ExtVectorElementExpr>(E)) 2036 return true; 2037 2038 return false; 2039} 2040 2041/// isArrow - Return true if the base expression is a pointer to vector, 2042/// return false if the base expression is a vector. 2043bool ExtVectorElementExpr::isArrow() const { 2044 return getBase()->getType()->isPointerType(); 2045} 2046 2047unsigned ExtVectorElementExpr::getNumElements() const { 2048 if (const VectorType *VT = getType()->getAs<VectorType>()) 2049 return VT->getNumElements(); 2050 return 1; 2051} 2052 2053/// containsDuplicateElements - Return true if any element access is repeated. 2054bool ExtVectorElementExpr::containsDuplicateElements() const { 2055 // FIXME: Refactor this code to an accessor on the AST node which returns the 2056 // "type" of component access, and share with code below and in Sema. 2057 llvm::StringRef Comp = Accessor->getName(); 2058 2059 // Halving swizzles do not contain duplicate elements. 2060 if (Comp == "hi" || Comp == "lo" || Comp == "even" || Comp == "odd") 2061 return false; 2062 2063 // Advance past s-char prefix on hex swizzles. 2064 if (Comp[0] == 's' || Comp[0] == 'S') 2065 Comp = Comp.substr(1); 2066 2067 for (unsigned i = 0, e = Comp.size(); i != e; ++i) 2068 if (Comp.substr(i + 1).find(Comp[i]) != llvm::StringRef::npos) 2069 return true; 2070 2071 return false; 2072} 2073 2074/// getEncodedElementAccess - We encode the fields as a llvm ConstantArray. 2075void ExtVectorElementExpr::getEncodedElementAccess( 2076 llvm::SmallVectorImpl<unsigned> &Elts) const { 2077 llvm::StringRef Comp = Accessor->getName(); 2078 if (Comp[0] == 's' || Comp[0] == 'S') 2079 Comp = Comp.substr(1); 2080 2081 bool isHi = Comp == "hi"; 2082 bool isLo = Comp == "lo"; 2083 bool isEven = Comp == "even"; 2084 bool isOdd = Comp == "odd"; 2085 2086 for (unsigned i = 0, e = getNumElements(); i != e; ++i) { 2087 uint64_t Index; 2088 2089 if (isHi) 2090 Index = e + i; 2091 else if (isLo) 2092 Index = i; 2093 else if (isEven) 2094 Index = 2 * i; 2095 else if (isOdd) 2096 Index = 2 * i + 1; 2097 else 2098 Index = ExtVectorType::getAccessorIdx(Comp[i]); 2099 2100 Elts.push_back(Index); 2101 } 2102} 2103 2104// constructor for instance messages. 2105ObjCMessageExpr::ObjCMessageExpr(ASTContext &C, Expr *receiver, 2106 Selector selInfo, 2107 QualType retType, ObjCMethodDecl *mproto, 2108 SourceLocation LBrac, SourceLocation RBrac, 2109 Expr **ArgExprs, unsigned nargs) 2110 : Expr(ObjCMessageExprClass, retType, false, false), SelName(selInfo), 2111 MethodProto(mproto) { 2112 NumArgs = nargs; 2113 SubExprs = new (C) Stmt*[NumArgs+1]; 2114 SubExprs[RECEIVER] = receiver; 2115 if (NumArgs) { 2116 for (unsigned i = 0; i != NumArgs; ++i) 2117 SubExprs[i+ARGS_START] = static_cast<Expr *>(ArgExprs[i]); 2118 } 2119 LBracloc = LBrac; 2120 RBracloc = RBrac; 2121} 2122 2123// constructor for class messages. 2124// FIXME: clsName should be typed to ObjCInterfaceType 2125ObjCMessageExpr::ObjCMessageExpr(ASTContext &C, IdentifierInfo *clsName, 2126 SourceLocation clsNameLoc, Selector selInfo, 2127 QualType retType, ObjCMethodDecl *mproto, 2128 SourceLocation LBrac, SourceLocation RBrac, 2129 Expr **ArgExprs, unsigned nargs) 2130 : Expr(ObjCMessageExprClass, retType, false, false), ClassNameLoc(clsNameLoc), 2131 SelName(selInfo), MethodProto(mproto) { 2132 NumArgs = nargs; 2133 SubExprs = new (C) Stmt*[NumArgs+1]; 2134 SubExprs[RECEIVER] = (Expr*) ((uintptr_t) clsName | IsClsMethDeclUnknown); 2135 if (NumArgs) { 2136 for (unsigned i = 0; i != NumArgs; ++i) 2137 SubExprs[i+ARGS_START] = static_cast<Expr *>(ArgExprs[i]); 2138 } 2139 LBracloc = LBrac; 2140 RBracloc = RBrac; 2141} 2142 2143// constructor for class messages. 2144ObjCMessageExpr::ObjCMessageExpr(ASTContext &C, ObjCInterfaceDecl *cls, 2145 SourceLocation clsNameLoc, Selector selInfo, 2146 QualType retType, 2147 ObjCMethodDecl *mproto, SourceLocation LBrac, 2148 SourceLocation RBrac, Expr **ArgExprs, 2149 unsigned nargs) 2150 : Expr(ObjCMessageExprClass, retType, false, false), ClassNameLoc(clsNameLoc), 2151 SelName(selInfo), MethodProto(mproto) 2152{ 2153 NumArgs = nargs; 2154 SubExprs = new (C) Stmt*[NumArgs+1]; 2155 SubExprs[RECEIVER] = (Expr*) ((uintptr_t) cls | IsClsMethDeclKnown); 2156 if (NumArgs) { 2157 for (unsigned i = 0; i != NumArgs; ++i) 2158 SubExprs[i+ARGS_START] = static_cast<Expr *>(ArgExprs[i]); 2159 } 2160 LBracloc = LBrac; 2161 RBracloc = RBrac; 2162} 2163 2164ObjCMessageExpr::ClassInfo ObjCMessageExpr::getClassInfo() const { 2165 uintptr_t x = (uintptr_t) SubExprs[RECEIVER]; 2166 switch (x & Flags) { 2167 default: 2168 assert(false && "Invalid ObjCMessageExpr."); 2169 case IsInstMeth: 2170 return ClassInfo(0, 0, SourceLocation()); 2171 case IsClsMethDeclUnknown: 2172 return ClassInfo(0, (IdentifierInfo*) (x & ~Flags), ClassNameLoc); 2173 case IsClsMethDeclKnown: { 2174 ObjCInterfaceDecl* D = (ObjCInterfaceDecl*) (x & ~Flags); 2175 return ClassInfo(D, D->getIdentifier(), ClassNameLoc); 2176 } 2177 } 2178} 2179 2180void ObjCMessageExpr::setClassInfo(const ObjCMessageExpr::ClassInfo &CI) { 2181 if (CI.Decl == 0 && CI.Name == 0) { 2182 SubExprs[RECEIVER] = (Expr*)((uintptr_t)0 | IsInstMeth); 2183 return; 2184 } 2185 2186 if (CI.Decl == 0) 2187 SubExprs[RECEIVER] = (Expr*)((uintptr_t)CI.Name | IsClsMethDeclUnknown); 2188 else 2189 SubExprs[RECEIVER] = (Expr*)((uintptr_t)CI.Decl | IsClsMethDeclKnown); 2190 ClassNameLoc = CI.Loc; 2191} 2192 2193void ObjCMessageExpr::DoDestroy(ASTContext &C) { 2194 DestroyChildren(C); 2195 if (SubExprs) 2196 C.Deallocate(SubExprs); 2197 this->~ObjCMessageExpr(); 2198 C.Deallocate((void*) this); 2199} 2200 2201bool ChooseExpr::isConditionTrue(ASTContext &C) const { 2202 return getCond()->EvaluateAsInt(C) != 0; 2203} 2204 2205void ShuffleVectorExpr::setExprs(ASTContext &C, Expr ** Exprs, 2206 unsigned NumExprs) { 2207 if (SubExprs) C.Deallocate(SubExprs); 2208 2209 SubExprs = new (C) Stmt* [NumExprs]; 2210 this->NumExprs = NumExprs; 2211 memcpy(SubExprs, Exprs, sizeof(Expr *) * NumExprs); 2212} 2213 2214void ShuffleVectorExpr::DoDestroy(ASTContext& C) { 2215 DestroyChildren(C); 2216 if (SubExprs) C.Deallocate(SubExprs); 2217 this->~ShuffleVectorExpr(); 2218 C.Deallocate(this); 2219} 2220 2221void SizeOfAlignOfExpr::DoDestroy(ASTContext& C) { 2222 // Override default behavior of traversing children. If this has a type 2223 // operand and the type is a variable-length array, the child iteration 2224 // will iterate over the size expression. However, this expression belongs 2225 // to the type, not to this, so we don't want to delete it. 2226 // We still want to delete this expression. 2227 if (isArgumentType()) { 2228 this->~SizeOfAlignOfExpr(); 2229 C.Deallocate(this); 2230 } 2231 else 2232 Expr::DoDestroy(C); 2233} 2234 2235//===----------------------------------------------------------------------===// 2236// DesignatedInitExpr 2237//===----------------------------------------------------------------------===// 2238 2239IdentifierInfo *DesignatedInitExpr::Designator::getFieldName() { 2240 assert(Kind == FieldDesignator && "Only valid on a field designator"); 2241 if (Field.NameOrField & 0x01) 2242 return reinterpret_cast<IdentifierInfo *>(Field.NameOrField&~0x01); 2243 else 2244 return getField()->getIdentifier(); 2245} 2246 2247DesignatedInitExpr::DesignatedInitExpr(ASTContext &C, QualType Ty, 2248 unsigned NumDesignators, 2249 const Designator *Designators, 2250 SourceLocation EqualOrColonLoc, 2251 bool GNUSyntax, 2252 Expr **IndexExprs, 2253 unsigned NumIndexExprs, 2254 Expr *Init) 2255 : Expr(DesignatedInitExprClass, Ty, 2256 Init->isTypeDependent(), Init->isValueDependent()), 2257 EqualOrColonLoc(EqualOrColonLoc), GNUSyntax(GNUSyntax), 2258 NumDesignators(NumDesignators), NumSubExprs(NumIndexExprs + 1) { 2259 this->Designators = new (C) Designator[NumDesignators]; 2260 2261 // Record the initializer itself. 2262 child_iterator Child = child_begin(); 2263 *Child++ = Init; 2264 2265 // Copy the designators and their subexpressions, computing 2266 // value-dependence along the way. 2267 unsigned IndexIdx = 0; 2268 for (unsigned I = 0; I != NumDesignators; ++I) { 2269 this->Designators[I] = Designators[I]; 2270 2271 if (this->Designators[I].isArrayDesignator()) { 2272 // Compute type- and value-dependence. 2273 Expr *Index = IndexExprs[IndexIdx]; 2274 ValueDependent = ValueDependent || 2275 Index->isTypeDependent() || Index->isValueDependent(); 2276 2277 // Copy the index expressions into permanent storage. 2278 *Child++ = IndexExprs[IndexIdx++]; 2279 } else if (this->Designators[I].isArrayRangeDesignator()) { 2280 // Compute type- and value-dependence. 2281 Expr *Start = IndexExprs[IndexIdx]; 2282 Expr *End = IndexExprs[IndexIdx + 1]; 2283 ValueDependent = ValueDependent || 2284 Start->isTypeDependent() || Start->isValueDependent() || 2285 End->isTypeDependent() || End->isValueDependent(); 2286 2287 // Copy the start/end expressions into permanent storage. 2288 *Child++ = IndexExprs[IndexIdx++]; 2289 *Child++ = IndexExprs[IndexIdx++]; 2290 } 2291 } 2292 2293 assert(IndexIdx == NumIndexExprs && "Wrong number of index expressions"); 2294} 2295 2296DesignatedInitExpr * 2297DesignatedInitExpr::Create(ASTContext &C, Designator *Designators, 2298 unsigned NumDesignators, 2299 Expr **IndexExprs, unsigned NumIndexExprs, 2300 SourceLocation ColonOrEqualLoc, 2301 bool UsesColonSyntax, Expr *Init) { 2302 void *Mem = C.Allocate(sizeof(DesignatedInitExpr) + 2303 sizeof(Stmt *) * (NumIndexExprs + 1), 8); 2304 return new (Mem) DesignatedInitExpr(C, C.VoidTy, NumDesignators, Designators, 2305 ColonOrEqualLoc, UsesColonSyntax, 2306 IndexExprs, NumIndexExprs, Init); 2307} 2308 2309DesignatedInitExpr *DesignatedInitExpr::CreateEmpty(ASTContext &C, 2310 unsigned NumIndexExprs) { 2311 void *Mem = C.Allocate(sizeof(DesignatedInitExpr) + 2312 sizeof(Stmt *) * (NumIndexExprs + 1), 8); 2313 return new (Mem) DesignatedInitExpr(NumIndexExprs + 1); 2314} 2315 2316void DesignatedInitExpr::setDesignators(ASTContext &C, 2317 const Designator *Desigs, 2318 unsigned NumDesigs) { 2319 DestroyDesignators(C); 2320 2321 Designators = new (C) Designator[NumDesigs]; 2322 NumDesignators = NumDesigs; 2323 for (unsigned I = 0; I != NumDesigs; ++I) 2324 Designators[I] = Desigs[I]; 2325} 2326 2327SourceRange DesignatedInitExpr::getSourceRange() const { 2328 SourceLocation StartLoc; 2329 Designator &First = 2330 *const_cast<DesignatedInitExpr*>(this)->designators_begin(); 2331 if (First.isFieldDesignator()) { 2332 if (GNUSyntax) 2333 StartLoc = SourceLocation::getFromRawEncoding(First.Field.FieldLoc); 2334 else 2335 StartLoc = SourceLocation::getFromRawEncoding(First.Field.DotLoc); 2336 } else 2337 StartLoc = 2338 SourceLocation::getFromRawEncoding(First.ArrayOrRange.LBracketLoc); 2339 return SourceRange(StartLoc, getInit()->getSourceRange().getEnd()); 2340} 2341 2342Expr *DesignatedInitExpr::getArrayIndex(const Designator& D) { 2343 assert(D.Kind == Designator::ArrayDesignator && "Requires array designator"); 2344 char* Ptr = static_cast<char*>(static_cast<void *>(this)); 2345 Ptr += sizeof(DesignatedInitExpr); 2346 Stmt **SubExprs = reinterpret_cast<Stmt**>(reinterpret_cast<void**>(Ptr)); 2347 return cast<Expr>(*(SubExprs + D.ArrayOrRange.Index + 1)); 2348} 2349 2350Expr *DesignatedInitExpr::getArrayRangeStart(const Designator& D) { 2351 assert(D.Kind == Designator::ArrayRangeDesignator && 2352 "Requires array range designator"); 2353 char* Ptr = static_cast<char*>(static_cast<void *>(this)); 2354 Ptr += sizeof(DesignatedInitExpr); 2355 Stmt **SubExprs = reinterpret_cast<Stmt**>(reinterpret_cast<void**>(Ptr)); 2356 return cast<Expr>(*(SubExprs + D.ArrayOrRange.Index + 1)); 2357} 2358 2359Expr *DesignatedInitExpr::getArrayRangeEnd(const Designator& D) { 2360 assert(D.Kind == Designator::ArrayRangeDesignator && 2361 "Requires array range designator"); 2362 char* Ptr = static_cast<char*>(static_cast<void *>(this)); 2363 Ptr += sizeof(DesignatedInitExpr); 2364 Stmt **SubExprs = reinterpret_cast<Stmt**>(reinterpret_cast<void**>(Ptr)); 2365 return cast<Expr>(*(SubExprs + D.ArrayOrRange.Index + 2)); 2366} 2367 2368/// \brief Replaces the designator at index @p Idx with the series 2369/// of designators in [First, Last). 2370void DesignatedInitExpr::ExpandDesignator(ASTContext &C, unsigned Idx, 2371 const Designator *First, 2372 const Designator *Last) { 2373 unsigned NumNewDesignators = Last - First; 2374 if (NumNewDesignators == 0) { 2375 std::copy_backward(Designators + Idx + 1, 2376 Designators + NumDesignators, 2377 Designators + Idx); 2378 --NumNewDesignators; 2379 return; 2380 } else if (NumNewDesignators == 1) { 2381 Designators[Idx] = *First; 2382 return; 2383 } 2384 2385 Designator *NewDesignators 2386 = new (C) Designator[NumDesignators - 1 + NumNewDesignators]; 2387 std::copy(Designators, Designators + Idx, NewDesignators); 2388 std::copy(First, Last, NewDesignators + Idx); 2389 std::copy(Designators + Idx + 1, Designators + NumDesignators, 2390 NewDesignators + Idx + NumNewDesignators); 2391 DestroyDesignators(C); 2392 Designators = NewDesignators; 2393 NumDesignators = NumDesignators - 1 + NumNewDesignators; 2394} 2395 2396void DesignatedInitExpr::DoDestroy(ASTContext &C) { 2397 DestroyDesignators(C); 2398 Expr::DoDestroy(C); 2399} 2400 2401void DesignatedInitExpr::DestroyDesignators(ASTContext &C) { 2402 for (unsigned I = 0; I != NumDesignators; ++I) 2403 Designators[I].~Designator(); 2404 C.Deallocate(Designators); 2405 Designators = 0; 2406} 2407 2408ParenListExpr::ParenListExpr(ASTContext& C, SourceLocation lparenloc, 2409 Expr **exprs, unsigned nexprs, 2410 SourceLocation rparenloc) 2411: Expr(ParenListExprClass, QualType(), 2412 hasAnyTypeDependentArguments(exprs, nexprs), 2413 hasAnyValueDependentArguments(exprs, nexprs)), 2414 NumExprs(nexprs), LParenLoc(lparenloc), RParenLoc(rparenloc) { 2415 2416 Exprs = new (C) Stmt*[nexprs]; 2417 for (unsigned i = 0; i != nexprs; ++i) 2418 Exprs[i] = exprs[i]; 2419} 2420 2421void ParenListExpr::DoDestroy(ASTContext& C) { 2422 DestroyChildren(C); 2423 if (Exprs) C.Deallocate(Exprs); 2424 this->~ParenListExpr(); 2425 C.Deallocate(this); 2426} 2427 2428//===----------------------------------------------------------------------===// 2429// ExprIterator. 2430//===----------------------------------------------------------------------===// 2431 2432Expr* ExprIterator::operator[](size_t idx) { return cast<Expr>(I[idx]); } 2433Expr* ExprIterator::operator*() const { return cast<Expr>(*I); } 2434Expr* ExprIterator::operator->() const { return cast<Expr>(*I); } 2435const Expr* ConstExprIterator::operator[](size_t idx) const { 2436 return cast<Expr>(I[idx]); 2437} 2438const Expr* ConstExprIterator::operator*() const { return cast<Expr>(*I); } 2439const Expr* ConstExprIterator::operator->() const { return cast<Expr>(*I); } 2440 2441//===----------------------------------------------------------------------===// 2442// Child Iterators for iterating over subexpressions/substatements 2443//===----------------------------------------------------------------------===// 2444 2445// DeclRefExpr 2446Stmt::child_iterator DeclRefExpr::child_begin() { return child_iterator(); } 2447Stmt::child_iterator DeclRefExpr::child_end() { return child_iterator(); } 2448 2449// ObjCIvarRefExpr 2450Stmt::child_iterator ObjCIvarRefExpr::child_begin() { return &Base; } 2451Stmt::child_iterator ObjCIvarRefExpr::child_end() { return &Base+1; } 2452 2453// ObjCPropertyRefExpr 2454Stmt::child_iterator ObjCPropertyRefExpr::child_begin() { return &Base; } 2455Stmt::child_iterator ObjCPropertyRefExpr::child_end() { return &Base+1; } 2456 2457// ObjCImplicitSetterGetterRefExpr 2458Stmt::child_iterator ObjCImplicitSetterGetterRefExpr::child_begin() { 2459 return &Base; 2460} 2461Stmt::child_iterator ObjCImplicitSetterGetterRefExpr::child_end() { 2462 return &Base+1; 2463} 2464 2465// ObjCSuperExpr 2466Stmt::child_iterator ObjCSuperExpr::child_begin() { return child_iterator(); } 2467Stmt::child_iterator ObjCSuperExpr::child_end() { return child_iterator(); } 2468 2469// ObjCIsaExpr 2470Stmt::child_iterator ObjCIsaExpr::child_begin() { return &Base; } 2471Stmt::child_iterator ObjCIsaExpr::child_end() { return &Base+1; } 2472 2473// PredefinedExpr 2474Stmt::child_iterator PredefinedExpr::child_begin() { return child_iterator(); } 2475Stmt::child_iterator PredefinedExpr::child_end() { return child_iterator(); } 2476 2477// IntegerLiteral 2478Stmt::child_iterator IntegerLiteral::child_begin() { return child_iterator(); } 2479Stmt::child_iterator IntegerLiteral::child_end() { return child_iterator(); } 2480 2481// CharacterLiteral 2482Stmt::child_iterator CharacterLiteral::child_begin() { return child_iterator();} 2483Stmt::child_iterator CharacterLiteral::child_end() { return child_iterator(); } 2484 2485// FloatingLiteral 2486Stmt::child_iterator FloatingLiteral::child_begin() { return child_iterator(); } 2487Stmt::child_iterator FloatingLiteral::child_end() { return child_iterator(); } 2488 2489// ImaginaryLiteral 2490Stmt::child_iterator ImaginaryLiteral::child_begin() { return &Val; } 2491Stmt::child_iterator ImaginaryLiteral::child_end() { return &Val+1; } 2492 2493// StringLiteral 2494Stmt::child_iterator StringLiteral::child_begin() { return child_iterator(); } 2495Stmt::child_iterator StringLiteral::child_end() { return child_iterator(); } 2496 2497// ParenExpr 2498Stmt::child_iterator ParenExpr::child_begin() { return &Val; } 2499Stmt::child_iterator ParenExpr::child_end() { return &Val+1; } 2500 2501// UnaryOperator 2502Stmt::child_iterator UnaryOperator::child_begin() { return &Val; } 2503Stmt::child_iterator UnaryOperator::child_end() { return &Val+1; } 2504 2505// SizeOfAlignOfExpr 2506Stmt::child_iterator SizeOfAlignOfExpr::child_begin() { 2507 // If this is of a type and the type is a VLA type (and not a typedef), the 2508 // size expression of the VLA needs to be treated as an executable expression. 2509 // Why isn't this weirdness documented better in StmtIterator? 2510 if (isArgumentType()) { 2511 if (VariableArrayType* T = dyn_cast<VariableArrayType>( 2512 getArgumentType().getTypePtr())) 2513 return child_iterator(T); 2514 return child_iterator(); 2515 } 2516 return child_iterator(&Argument.Ex); 2517} 2518Stmt::child_iterator SizeOfAlignOfExpr::child_end() { 2519 if (isArgumentType()) 2520 return child_iterator(); 2521 return child_iterator(&Argument.Ex + 1); 2522} 2523 2524// ArraySubscriptExpr 2525Stmt::child_iterator ArraySubscriptExpr::child_begin() { 2526 return &SubExprs[0]; 2527} 2528Stmt::child_iterator ArraySubscriptExpr::child_end() { 2529 return &SubExprs[0]+END_EXPR; 2530} 2531 2532// CallExpr 2533Stmt::child_iterator CallExpr::child_begin() { 2534 return &SubExprs[0]; 2535} 2536Stmt::child_iterator CallExpr::child_end() { 2537 return &SubExprs[0]+NumArgs+ARGS_START; 2538} 2539 2540// MemberExpr 2541Stmt::child_iterator MemberExpr::child_begin() { return &Base; } 2542Stmt::child_iterator MemberExpr::child_end() { return &Base+1; } 2543 2544// ExtVectorElementExpr 2545Stmt::child_iterator ExtVectorElementExpr::child_begin() { return &Base; } 2546Stmt::child_iterator ExtVectorElementExpr::child_end() { return &Base+1; } 2547 2548// CompoundLiteralExpr 2549Stmt::child_iterator CompoundLiteralExpr::child_begin() { return &Init; } 2550Stmt::child_iterator CompoundLiteralExpr::child_end() { return &Init+1; } 2551 2552// CastExpr 2553Stmt::child_iterator CastExpr::child_begin() { return &Op; } 2554Stmt::child_iterator CastExpr::child_end() { return &Op+1; } 2555 2556// BinaryOperator 2557Stmt::child_iterator BinaryOperator::child_begin() { 2558 return &SubExprs[0]; 2559} 2560Stmt::child_iterator BinaryOperator::child_end() { 2561 return &SubExprs[0]+END_EXPR; 2562} 2563 2564// ConditionalOperator 2565Stmt::child_iterator ConditionalOperator::child_begin() { 2566 return &SubExprs[0]; 2567} 2568Stmt::child_iterator ConditionalOperator::child_end() { 2569 return &SubExprs[0]+END_EXPR; 2570} 2571 2572// AddrLabelExpr 2573Stmt::child_iterator AddrLabelExpr::child_begin() { return child_iterator(); } 2574Stmt::child_iterator AddrLabelExpr::child_end() { return child_iterator(); } 2575 2576// StmtExpr 2577Stmt::child_iterator StmtExpr::child_begin() { return &SubStmt; } 2578Stmt::child_iterator StmtExpr::child_end() { return &SubStmt+1; } 2579 2580// TypesCompatibleExpr 2581Stmt::child_iterator TypesCompatibleExpr::child_begin() { 2582 return child_iterator(); 2583} 2584 2585Stmt::child_iterator TypesCompatibleExpr::child_end() { 2586 return child_iterator(); 2587} 2588 2589// ChooseExpr 2590Stmt::child_iterator ChooseExpr::child_begin() { return &SubExprs[0]; } 2591Stmt::child_iterator ChooseExpr::child_end() { return &SubExprs[0]+END_EXPR; } 2592 2593// GNUNullExpr 2594Stmt::child_iterator GNUNullExpr::child_begin() { return child_iterator(); } 2595Stmt::child_iterator GNUNullExpr::child_end() { return child_iterator(); } 2596 2597// ShuffleVectorExpr 2598Stmt::child_iterator ShuffleVectorExpr::child_begin() { 2599 return &SubExprs[0]; 2600} 2601Stmt::child_iterator ShuffleVectorExpr::child_end() { 2602 return &SubExprs[0]+NumExprs; 2603} 2604 2605// VAArgExpr 2606Stmt::child_iterator VAArgExpr::child_begin() { return &Val; } 2607Stmt::child_iterator VAArgExpr::child_end() { return &Val+1; } 2608 2609// InitListExpr 2610Stmt::child_iterator InitListExpr::child_begin() { 2611 return InitExprs.size() ? &InitExprs[0] : 0; 2612} 2613Stmt::child_iterator InitListExpr::child_end() { 2614 return InitExprs.size() ? &InitExprs[0] + InitExprs.size() : 0; 2615} 2616 2617// DesignatedInitExpr 2618Stmt::child_iterator DesignatedInitExpr::child_begin() { 2619 char* Ptr = static_cast<char*>(static_cast<void *>(this)); 2620 Ptr += sizeof(DesignatedInitExpr); 2621 return reinterpret_cast<Stmt**>(reinterpret_cast<void**>(Ptr)); 2622} 2623Stmt::child_iterator DesignatedInitExpr::child_end() { 2624 return child_iterator(&*child_begin() + NumSubExprs); 2625} 2626 2627// ImplicitValueInitExpr 2628Stmt::child_iterator ImplicitValueInitExpr::child_begin() { 2629 return child_iterator(); 2630} 2631 2632Stmt::child_iterator ImplicitValueInitExpr::child_end() { 2633 return child_iterator(); 2634} 2635 2636// ParenListExpr 2637Stmt::child_iterator ParenListExpr::child_begin() { 2638 return &Exprs[0]; 2639} 2640Stmt::child_iterator ParenListExpr::child_end() { 2641 return &Exprs[0]+NumExprs; 2642} 2643 2644// ObjCStringLiteral 2645Stmt::child_iterator ObjCStringLiteral::child_begin() { 2646 return &String; 2647} 2648Stmt::child_iterator ObjCStringLiteral::child_end() { 2649 return &String+1; 2650} 2651 2652// ObjCEncodeExpr 2653Stmt::child_iterator ObjCEncodeExpr::child_begin() { return child_iterator(); } 2654Stmt::child_iterator ObjCEncodeExpr::child_end() { return child_iterator(); } 2655 2656// ObjCSelectorExpr 2657Stmt::child_iterator ObjCSelectorExpr::child_begin() { 2658 return child_iterator(); 2659} 2660Stmt::child_iterator ObjCSelectorExpr::child_end() { 2661 return child_iterator(); 2662} 2663 2664// ObjCProtocolExpr 2665Stmt::child_iterator ObjCProtocolExpr::child_begin() { 2666 return child_iterator(); 2667} 2668Stmt::child_iterator ObjCProtocolExpr::child_end() { 2669 return child_iterator(); 2670} 2671 2672// ObjCMessageExpr 2673Stmt::child_iterator ObjCMessageExpr::child_begin() { 2674 return getReceiver() ? &SubExprs[0] : &SubExprs[0] + ARGS_START; 2675} 2676Stmt::child_iterator ObjCMessageExpr::child_end() { 2677 return &SubExprs[0]+ARGS_START+getNumArgs(); 2678} 2679 2680// Blocks 2681Stmt::child_iterator BlockExpr::child_begin() { return child_iterator(); } 2682Stmt::child_iterator BlockExpr::child_end() { return child_iterator(); } 2683 2684Stmt::child_iterator BlockDeclRefExpr::child_begin() { return child_iterator();} 2685Stmt::child_iterator BlockDeclRefExpr::child_end() { return child_iterator(); } 2686