Expr.cpp revision 90c71268f04369328e8f579007b8b4f1da9feea0
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 Out << MD->getClassInterface()->getNameAsString(); 231 if (const ObjCCategoryImplDecl *CID = 232 dyn_cast<ObjCCategoryImplDecl>(MD->getDeclContext())) { 233 Out << '('; 234 Out << CID->getNameAsString(); 235 Out << ')'; 236 } 237 Out << ' '; 238 Out << MD->getSelector().getAsString(); 239 Out << ']'; 240 241 Out.flush(); 242 return Name.str().str(); 243 } 244 if (isa<TranslationUnitDecl>(CurrentDecl) && IT == PrettyFunction) { 245 // __PRETTY_FUNCTION__ -> "top level", the others produce an empty string. 246 return "top level"; 247 } 248 return ""; 249} 250 251/// getValueAsApproximateDouble - This returns the value as an inaccurate 252/// double. Note that this may cause loss of precision, but is useful for 253/// debugging dumps, etc. 254double FloatingLiteral::getValueAsApproximateDouble() const { 255 llvm::APFloat V = getValue(); 256 bool ignored; 257 V.convert(llvm::APFloat::IEEEdouble, llvm::APFloat::rmNearestTiesToEven, 258 &ignored); 259 return V.convertToDouble(); 260} 261 262StringLiteral *StringLiteral::Create(ASTContext &C, const char *StrData, 263 unsigned ByteLength, bool Wide, 264 QualType Ty, 265 const SourceLocation *Loc, 266 unsigned NumStrs) { 267 // Allocate enough space for the StringLiteral plus an array of locations for 268 // any concatenated string tokens. 269 void *Mem = C.Allocate(sizeof(StringLiteral)+ 270 sizeof(SourceLocation)*(NumStrs-1), 271 llvm::alignof<StringLiteral>()); 272 StringLiteral *SL = new (Mem) StringLiteral(Ty); 273 274 // OPTIMIZE: could allocate this appended to the StringLiteral. 275 char *AStrData = new (C, 1) char[ByteLength]; 276 memcpy(AStrData, StrData, ByteLength); 277 SL->StrData = AStrData; 278 SL->ByteLength = ByteLength; 279 SL->IsWide = Wide; 280 SL->TokLocs[0] = Loc[0]; 281 SL->NumConcatenated = NumStrs; 282 283 if (NumStrs != 1) 284 memcpy(&SL->TokLocs[1], Loc+1, sizeof(SourceLocation)*(NumStrs-1)); 285 return SL; 286} 287 288StringLiteral *StringLiteral::CreateEmpty(ASTContext &C, unsigned NumStrs) { 289 void *Mem = C.Allocate(sizeof(StringLiteral)+ 290 sizeof(SourceLocation)*(NumStrs-1), 291 llvm::alignof<StringLiteral>()); 292 StringLiteral *SL = new (Mem) StringLiteral(QualType()); 293 SL->StrData = 0; 294 SL->ByteLength = 0; 295 SL->NumConcatenated = NumStrs; 296 return SL; 297} 298 299void StringLiteral::DoDestroy(ASTContext &C) { 300 C.Deallocate(const_cast<char*>(StrData)); 301 Expr::DoDestroy(C); 302} 303 304void StringLiteral::setString(ASTContext &C, llvm::StringRef Str) { 305 if (StrData) 306 C.Deallocate(const_cast<char*>(StrData)); 307 308 char *AStrData = new (C, 1) char[Str.size()]; 309 memcpy(AStrData, Str.data(), Str.size()); 310 StrData = AStrData; 311 ByteLength = Str.size(); 312} 313 314/// getOpcodeStr - Turn an Opcode enum value into the punctuation char it 315/// corresponds to, e.g. "sizeof" or "[pre]++". 316const char *UnaryOperator::getOpcodeStr(Opcode Op) { 317 switch (Op) { 318 default: assert(0 && "Unknown unary operator"); 319 case PostInc: return "++"; 320 case PostDec: return "--"; 321 case PreInc: return "++"; 322 case PreDec: return "--"; 323 case AddrOf: return "&"; 324 case Deref: return "*"; 325 case Plus: return "+"; 326 case Minus: return "-"; 327 case Not: return "~"; 328 case LNot: return "!"; 329 case Real: return "__real"; 330 case Imag: return "__imag"; 331 case Extension: return "__extension__"; 332 case OffsetOf: return "__builtin_offsetof"; 333 } 334} 335 336UnaryOperator::Opcode 337UnaryOperator::getOverloadedOpcode(OverloadedOperatorKind OO, bool Postfix) { 338 switch (OO) { 339 default: assert(false && "No unary operator for overloaded function"); 340 case OO_PlusPlus: return Postfix ? PostInc : PreInc; 341 case OO_MinusMinus: return Postfix ? PostDec : PreDec; 342 case OO_Amp: return AddrOf; 343 case OO_Star: return Deref; 344 case OO_Plus: return Plus; 345 case OO_Minus: return Minus; 346 case OO_Tilde: return Not; 347 case OO_Exclaim: return LNot; 348 } 349} 350 351OverloadedOperatorKind UnaryOperator::getOverloadedOperator(Opcode Opc) { 352 switch (Opc) { 353 case PostInc: case PreInc: return OO_PlusPlus; 354 case PostDec: case PreDec: return OO_MinusMinus; 355 case AddrOf: return OO_Amp; 356 case Deref: return OO_Star; 357 case Plus: return OO_Plus; 358 case Minus: return OO_Minus; 359 case Not: return OO_Tilde; 360 case LNot: return OO_Exclaim; 361 default: return OO_None; 362 } 363} 364 365 366//===----------------------------------------------------------------------===// 367// Postfix Operators. 368//===----------------------------------------------------------------------===// 369 370CallExpr::CallExpr(ASTContext& C, StmtClass SC, Expr *fn, Expr **args, 371 unsigned numargs, QualType t, SourceLocation rparenloc) 372 : Expr(SC, t, 373 fn->isTypeDependent() || hasAnyTypeDependentArguments(args, numargs), 374 fn->isValueDependent() || hasAnyValueDependentArguments(args,numargs)), 375 NumArgs(numargs) { 376 377 SubExprs = new (C) Stmt*[numargs+1]; 378 SubExprs[FN] = fn; 379 for (unsigned i = 0; i != numargs; ++i) 380 SubExprs[i+ARGS_START] = args[i]; 381 382 RParenLoc = rparenloc; 383} 384 385CallExpr::CallExpr(ASTContext& C, Expr *fn, Expr **args, unsigned numargs, 386 QualType t, SourceLocation rparenloc) 387 : Expr(CallExprClass, t, 388 fn->isTypeDependent() || hasAnyTypeDependentArguments(args, numargs), 389 fn->isValueDependent() || hasAnyValueDependentArguments(args,numargs)), 390 NumArgs(numargs) { 391 392 SubExprs = new (C) Stmt*[numargs+1]; 393 SubExprs[FN] = fn; 394 for (unsigned i = 0; i != numargs; ++i) 395 SubExprs[i+ARGS_START] = args[i]; 396 397 RParenLoc = rparenloc; 398} 399 400CallExpr::CallExpr(ASTContext &C, StmtClass SC, EmptyShell Empty) 401 : Expr(SC, Empty), SubExprs(0), NumArgs(0) { 402 SubExprs = new (C) Stmt*[1]; 403} 404 405void CallExpr::DoDestroy(ASTContext& C) { 406 DestroyChildren(C); 407 if (SubExprs) C.Deallocate(SubExprs); 408 this->~CallExpr(); 409 C.Deallocate(this); 410} 411 412Decl *CallExpr::getCalleeDecl() { 413 Expr *CEE = getCallee()->IgnoreParenCasts(); 414 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) 415 return DRE->getDecl(); 416 if (MemberExpr *ME = dyn_cast<MemberExpr>(CEE)) 417 return ME->getMemberDecl(); 418 419 return 0; 420} 421 422FunctionDecl *CallExpr::getDirectCallee() { 423 return dyn_cast_or_null<FunctionDecl>(getCalleeDecl()); 424} 425 426/// setNumArgs - This changes the number of arguments present in this call. 427/// Any orphaned expressions are deleted by this, and any new operands are set 428/// to null. 429void CallExpr::setNumArgs(ASTContext& C, unsigned NumArgs) { 430 // No change, just return. 431 if (NumArgs == getNumArgs()) return; 432 433 // If shrinking # arguments, just delete the extras and forgot them. 434 if (NumArgs < getNumArgs()) { 435 for (unsigned i = NumArgs, e = getNumArgs(); i != e; ++i) 436 getArg(i)->Destroy(C); 437 this->NumArgs = NumArgs; 438 return; 439 } 440 441 // Otherwise, we are growing the # arguments. New an bigger argument array. 442 Stmt **NewSubExprs = new (C) Stmt*[NumArgs+1]; 443 // Copy over args. 444 for (unsigned i = 0; i != getNumArgs()+ARGS_START; ++i) 445 NewSubExprs[i] = SubExprs[i]; 446 // Null out new args. 447 for (unsigned i = getNumArgs()+ARGS_START; i != NumArgs+ARGS_START; ++i) 448 NewSubExprs[i] = 0; 449 450 if (SubExprs) C.Deallocate(SubExprs); 451 SubExprs = NewSubExprs; 452 this->NumArgs = NumArgs; 453} 454 455/// isBuiltinCall - If this is a call to a builtin, return the builtin ID. If 456/// not, return 0. 457unsigned CallExpr::isBuiltinCall(ASTContext &Context) const { 458 // All simple function calls (e.g. func()) are implicitly cast to pointer to 459 // function. As a result, we try and obtain the DeclRefExpr from the 460 // ImplicitCastExpr. 461 const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(getCallee()); 462 if (!ICE) // FIXME: deal with more complex calls (e.g. (func)(), (*func)()). 463 return 0; 464 465 const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ICE->getSubExpr()); 466 if (!DRE) 467 return 0; 468 469 const FunctionDecl *FDecl = dyn_cast<FunctionDecl>(DRE->getDecl()); 470 if (!FDecl) 471 return 0; 472 473 if (!FDecl->getIdentifier()) 474 return 0; 475 476 return FDecl->getBuiltinID(); 477} 478 479QualType CallExpr::getCallReturnType() const { 480 QualType CalleeType = getCallee()->getType(); 481 if (const PointerType *FnTypePtr = CalleeType->getAs<PointerType>()) 482 CalleeType = FnTypePtr->getPointeeType(); 483 else if (const BlockPointerType *BPT = CalleeType->getAs<BlockPointerType>()) 484 CalleeType = BPT->getPointeeType(); 485 486 const FunctionType *FnType = CalleeType->getAs<FunctionType>(); 487 return FnType->getResultType(); 488} 489 490MemberExpr::MemberExpr(Expr *base, bool isarrow, NestedNameSpecifier *qual, 491 SourceRange qualrange, ValueDecl *memberdecl, 492 SourceLocation l, const TemplateArgumentListInfo *targs, 493 QualType ty) 494 : Expr(MemberExprClass, ty, 495 base->isTypeDependent() || (qual && qual->isDependent()), 496 base->isValueDependent() || (qual && qual->isDependent())), 497 Base(base), MemberDecl(memberdecl), MemberLoc(l), IsArrow(isarrow), 498 HasQualifier(qual != 0), HasExplicitTemplateArgumentList(targs) { 499 // Initialize the qualifier, if any. 500 if (HasQualifier) { 501 NameQualifier *NQ = getMemberQualifier(); 502 NQ->NNS = qual; 503 NQ->Range = qualrange; 504 } 505 506 // Initialize the explicit template argument list, if any. 507 if (targs) 508 getExplicitTemplateArgumentList()->initializeFrom(*targs); 509} 510 511MemberExpr *MemberExpr::Create(ASTContext &C, Expr *base, bool isarrow, 512 NestedNameSpecifier *qual, 513 SourceRange qualrange, 514 ValueDecl *memberdecl, 515 SourceLocation l, 516 const TemplateArgumentListInfo *targs, 517 QualType ty) { 518 std::size_t Size = sizeof(MemberExpr); 519 if (qual != 0) 520 Size += sizeof(NameQualifier); 521 522 if (targs) 523 Size += ExplicitTemplateArgumentList::sizeFor(*targs); 524 525 void *Mem = C.Allocate(Size, llvm::alignof<MemberExpr>()); 526 return new (Mem) MemberExpr(base, isarrow, qual, qualrange, memberdecl, l, 527 targs, ty); 528} 529 530const char *CastExpr::getCastKindName() const { 531 switch (getCastKind()) { 532 case CastExpr::CK_Unknown: 533 return "Unknown"; 534 case CastExpr::CK_BitCast: 535 return "BitCast"; 536 case CastExpr::CK_NoOp: 537 return "NoOp"; 538 case CastExpr::CK_BaseToDerived: 539 return "BaseToDerived"; 540 case CastExpr::CK_DerivedToBase: 541 return "DerivedToBase"; 542 case CastExpr::CK_Dynamic: 543 return "Dynamic"; 544 case CastExpr::CK_ToUnion: 545 return "ToUnion"; 546 case CastExpr::CK_ArrayToPointerDecay: 547 return "ArrayToPointerDecay"; 548 case CastExpr::CK_FunctionToPointerDecay: 549 return "FunctionToPointerDecay"; 550 case CastExpr::CK_NullToMemberPointer: 551 return "NullToMemberPointer"; 552 case CastExpr::CK_BaseToDerivedMemberPointer: 553 return "BaseToDerivedMemberPointer"; 554 case CastExpr::CK_DerivedToBaseMemberPointer: 555 return "DerivedToBaseMemberPointer"; 556 case CastExpr::CK_UserDefinedConversion: 557 return "UserDefinedConversion"; 558 case CastExpr::CK_ConstructorConversion: 559 return "ConstructorConversion"; 560 case CastExpr::CK_IntegralToPointer: 561 return "IntegralToPointer"; 562 case CastExpr::CK_PointerToIntegral: 563 return "PointerToIntegral"; 564 case CastExpr::CK_ToVoid: 565 return "ToVoid"; 566 case CastExpr::CK_VectorSplat: 567 return "VectorSplat"; 568 case CastExpr::CK_IntegralCast: 569 return "IntegralCast"; 570 case CastExpr::CK_IntegralToFloating: 571 return "IntegralToFloating"; 572 case CastExpr::CK_FloatingToIntegral: 573 return "FloatingToIntegral"; 574 case CastExpr::CK_FloatingCast: 575 return "FloatingCast"; 576 case CastExpr::CK_MemberPointerToBoolean: 577 return "MemberPointerToBoolean"; 578 case CastExpr::CK_AnyPointerToObjCPointerCast: 579 return "AnyPointerToObjCPointerCast"; 580 case CastExpr::CK_AnyPointerToBlockPointerCast: 581 return "AnyPointerToBlockPointerCast"; 582 } 583 584 assert(0 && "Unhandled cast kind!"); 585 return 0; 586} 587 588Expr *CastExpr::getSubExprAsWritten() { 589 Expr *SubExpr = 0; 590 CastExpr *E = this; 591 do { 592 SubExpr = E->getSubExpr(); 593 594 // Skip any temporary bindings; they're implicit. 595 if (CXXBindTemporaryExpr *Binder = dyn_cast<CXXBindTemporaryExpr>(SubExpr)) 596 SubExpr = Binder->getSubExpr(); 597 598 // Conversions by constructor and conversion functions have a 599 // subexpression describing the call; strip it off. 600 if (E->getCastKind() == CastExpr::CK_ConstructorConversion) 601 SubExpr = cast<CXXConstructExpr>(SubExpr)->getArg(0); 602 else if (E->getCastKind() == CastExpr::CK_UserDefinedConversion) 603 SubExpr = cast<CXXMemberCallExpr>(SubExpr)->getImplicitObjectArgument(); 604 605 // If the subexpression we're left with is an implicit cast, look 606 // through that, too. 607 } while ((E = dyn_cast<ImplicitCastExpr>(SubExpr))); 608 609 return SubExpr; 610} 611 612/// getOpcodeStr - Turn an Opcode enum value into the punctuation char it 613/// corresponds to, e.g. "<<=". 614const char *BinaryOperator::getOpcodeStr(Opcode Op) { 615 switch (Op) { 616 case PtrMemD: return ".*"; 617 case PtrMemI: return "->*"; 618 case Mul: return "*"; 619 case Div: return "/"; 620 case Rem: return "%"; 621 case Add: return "+"; 622 case Sub: return "-"; 623 case Shl: return "<<"; 624 case Shr: return ">>"; 625 case LT: return "<"; 626 case GT: return ">"; 627 case LE: return "<="; 628 case GE: return ">="; 629 case EQ: return "=="; 630 case NE: return "!="; 631 case And: return "&"; 632 case Xor: return "^"; 633 case Or: return "|"; 634 case LAnd: return "&&"; 635 case LOr: return "||"; 636 case Assign: return "="; 637 case MulAssign: return "*="; 638 case DivAssign: return "/="; 639 case RemAssign: return "%="; 640 case AddAssign: return "+="; 641 case SubAssign: return "-="; 642 case ShlAssign: return "<<="; 643 case ShrAssign: return ">>="; 644 case AndAssign: return "&="; 645 case XorAssign: return "^="; 646 case OrAssign: return "|="; 647 case Comma: return ","; 648 } 649 650 return ""; 651} 652 653BinaryOperator::Opcode 654BinaryOperator::getOverloadedOpcode(OverloadedOperatorKind OO) { 655 switch (OO) { 656 default: assert(false && "Not an overloadable binary operator"); 657 case OO_Plus: return Add; 658 case OO_Minus: return Sub; 659 case OO_Star: return Mul; 660 case OO_Slash: return Div; 661 case OO_Percent: return Rem; 662 case OO_Caret: return Xor; 663 case OO_Amp: return And; 664 case OO_Pipe: return Or; 665 case OO_Equal: return Assign; 666 case OO_Less: return LT; 667 case OO_Greater: return GT; 668 case OO_PlusEqual: return AddAssign; 669 case OO_MinusEqual: return SubAssign; 670 case OO_StarEqual: return MulAssign; 671 case OO_SlashEqual: return DivAssign; 672 case OO_PercentEqual: return RemAssign; 673 case OO_CaretEqual: return XorAssign; 674 case OO_AmpEqual: return AndAssign; 675 case OO_PipeEqual: return OrAssign; 676 case OO_LessLess: return Shl; 677 case OO_GreaterGreater: return Shr; 678 case OO_LessLessEqual: return ShlAssign; 679 case OO_GreaterGreaterEqual: return ShrAssign; 680 case OO_EqualEqual: return EQ; 681 case OO_ExclaimEqual: return NE; 682 case OO_LessEqual: return LE; 683 case OO_GreaterEqual: return GE; 684 case OO_AmpAmp: return LAnd; 685 case OO_PipePipe: return LOr; 686 case OO_Comma: return Comma; 687 case OO_ArrowStar: return PtrMemI; 688 } 689} 690 691OverloadedOperatorKind BinaryOperator::getOverloadedOperator(Opcode Opc) { 692 static const OverloadedOperatorKind OverOps[] = { 693 /* .* Cannot be overloaded */OO_None, OO_ArrowStar, 694 OO_Star, OO_Slash, OO_Percent, 695 OO_Plus, OO_Minus, 696 OO_LessLess, OO_GreaterGreater, 697 OO_Less, OO_Greater, OO_LessEqual, OO_GreaterEqual, 698 OO_EqualEqual, OO_ExclaimEqual, 699 OO_Amp, 700 OO_Caret, 701 OO_Pipe, 702 OO_AmpAmp, 703 OO_PipePipe, 704 OO_Equal, OO_StarEqual, 705 OO_SlashEqual, OO_PercentEqual, 706 OO_PlusEqual, OO_MinusEqual, 707 OO_LessLessEqual, OO_GreaterGreaterEqual, 708 OO_AmpEqual, OO_CaretEqual, 709 OO_PipeEqual, 710 OO_Comma 711 }; 712 return OverOps[Opc]; 713} 714 715InitListExpr::InitListExpr(SourceLocation lbraceloc, 716 Expr **initExprs, unsigned numInits, 717 SourceLocation rbraceloc) 718 : Expr(InitListExprClass, QualType(), false, false), 719 LBraceLoc(lbraceloc), RBraceLoc(rbraceloc), SyntacticForm(0), 720 UnionFieldInit(0), HadArrayRangeDesignator(false) 721{ 722 for (unsigned I = 0; I != numInits; ++I) { 723 if (initExprs[I]->isTypeDependent()) 724 TypeDependent = true; 725 if (initExprs[I]->isValueDependent()) 726 ValueDependent = true; 727 } 728 729 InitExprs.insert(InitExprs.end(), initExprs, initExprs+numInits); 730} 731 732void InitListExpr::reserveInits(unsigned NumInits) { 733 if (NumInits > InitExprs.size()) 734 InitExprs.reserve(NumInits); 735} 736 737void InitListExpr::resizeInits(ASTContext &Context, unsigned NumInits) { 738 for (unsigned Idx = NumInits, LastIdx = InitExprs.size(); 739 Idx < LastIdx; ++Idx) 740 InitExprs[Idx]->Destroy(Context); 741 InitExprs.resize(NumInits, 0); 742} 743 744Expr *InitListExpr::updateInit(unsigned Init, Expr *expr) { 745 if (Init >= InitExprs.size()) { 746 InitExprs.insert(InitExprs.end(), Init - InitExprs.size() + 1, 0); 747 InitExprs.back() = expr; 748 return 0; 749 } 750 751 Expr *Result = cast_or_null<Expr>(InitExprs[Init]); 752 InitExprs[Init] = expr; 753 return Result; 754} 755 756/// getFunctionType - Return the underlying function type for this block. 757/// 758const FunctionType *BlockExpr::getFunctionType() const { 759 return getType()->getAs<BlockPointerType>()-> 760 getPointeeType()->getAs<FunctionType>(); 761} 762 763SourceLocation BlockExpr::getCaretLocation() const { 764 return TheBlock->getCaretLocation(); 765} 766const Stmt *BlockExpr::getBody() const { 767 return TheBlock->getBody(); 768} 769Stmt *BlockExpr::getBody() { 770 return TheBlock->getBody(); 771} 772 773 774//===----------------------------------------------------------------------===// 775// Generic Expression Routines 776//===----------------------------------------------------------------------===// 777 778/// isUnusedResultAWarning - Return true if this immediate expression should 779/// be warned about if the result is unused. If so, fill in Loc and Ranges 780/// with location to warn on and the source range[s] to report with the 781/// warning. 782bool Expr::isUnusedResultAWarning(SourceLocation &Loc, SourceRange &R1, 783 SourceRange &R2, ASTContext &Ctx) const { 784 // Don't warn if the expr is type dependent. The type could end up 785 // instantiating to void. 786 if (isTypeDependent()) 787 return false; 788 789 switch (getStmtClass()) { 790 default: 791 if (getType()->isVoidType()) 792 return false; 793 Loc = getExprLoc(); 794 R1 = getSourceRange(); 795 return true; 796 case ParenExprClass: 797 return cast<ParenExpr>(this)->getSubExpr()-> 798 isUnusedResultAWarning(Loc, R1, R2, Ctx); 799 case UnaryOperatorClass: { 800 const UnaryOperator *UO = cast<UnaryOperator>(this); 801 802 switch (UO->getOpcode()) { 803 default: break; 804 case UnaryOperator::PostInc: 805 case UnaryOperator::PostDec: 806 case UnaryOperator::PreInc: 807 case UnaryOperator::PreDec: // ++/-- 808 return false; // Not a warning. 809 case UnaryOperator::Deref: 810 // Dereferencing a volatile pointer is a side-effect. 811 if (Ctx.getCanonicalType(getType()).isVolatileQualified()) 812 return false; 813 break; 814 case UnaryOperator::Real: 815 case UnaryOperator::Imag: 816 // accessing a piece of a volatile complex is a side-effect. 817 if (Ctx.getCanonicalType(UO->getSubExpr()->getType()) 818 .isVolatileQualified()) 819 return false; 820 break; 821 case UnaryOperator::Extension: 822 return UO->getSubExpr()->isUnusedResultAWarning(Loc, R1, R2, Ctx); 823 } 824 Loc = UO->getOperatorLoc(); 825 R1 = UO->getSubExpr()->getSourceRange(); 826 return true; 827 } 828 case BinaryOperatorClass: { 829 const BinaryOperator *BO = cast<BinaryOperator>(this); 830 // Consider comma to have side effects if the LHS or RHS does. 831 if (BO->getOpcode() == BinaryOperator::Comma) { 832 // ((foo = <blah>), 0) is an idiom for hiding the result (and 833 // lvalue-ness) of an assignment written in a macro. 834 if (IntegerLiteral *IE = 835 dyn_cast<IntegerLiteral>(BO->getRHS()->IgnoreParens())) 836 if (IE->getValue() == 0) 837 return false; 838 839 return (BO->getLHS()->isUnusedResultAWarning(Loc, R1, R2, Ctx) || 840 BO->getRHS()->isUnusedResultAWarning(Loc, R1, R2, Ctx)); 841 } 842 843 if (BO->isAssignmentOp()) 844 return false; 845 Loc = BO->getOperatorLoc(); 846 R1 = BO->getLHS()->getSourceRange(); 847 R2 = BO->getRHS()->getSourceRange(); 848 return true; 849 } 850 case CompoundAssignOperatorClass: 851 return false; 852 853 case ConditionalOperatorClass: { 854 // The condition must be evaluated, but if either the LHS or RHS is a 855 // warning, warn about them. 856 const ConditionalOperator *Exp = cast<ConditionalOperator>(this); 857 if (Exp->getLHS() && 858 Exp->getLHS()->isUnusedResultAWarning(Loc, R1, R2, Ctx)) 859 return true; 860 return Exp->getRHS()->isUnusedResultAWarning(Loc, R1, R2, Ctx); 861 } 862 863 case MemberExprClass: 864 // If the base pointer or element is to a volatile pointer/field, accessing 865 // it is a side effect. 866 if (Ctx.getCanonicalType(getType()).isVolatileQualified()) 867 return false; 868 Loc = cast<MemberExpr>(this)->getMemberLoc(); 869 R1 = SourceRange(Loc, Loc); 870 R2 = cast<MemberExpr>(this)->getBase()->getSourceRange(); 871 return true; 872 873 case ArraySubscriptExprClass: 874 // If the base pointer or element is to a volatile pointer/field, accessing 875 // it is a side effect. 876 if (Ctx.getCanonicalType(getType()).isVolatileQualified()) 877 return false; 878 Loc = cast<ArraySubscriptExpr>(this)->getRBracketLoc(); 879 R1 = cast<ArraySubscriptExpr>(this)->getLHS()->getSourceRange(); 880 R2 = cast<ArraySubscriptExpr>(this)->getRHS()->getSourceRange(); 881 return true; 882 883 case CallExprClass: 884 case CXXOperatorCallExprClass: 885 case CXXMemberCallExprClass: { 886 // If this is a direct call, get the callee. 887 const CallExpr *CE = cast<CallExpr>(this); 888 if (const Decl *FD = CE->getCalleeDecl()) { 889 // If the callee has attribute pure, const, or warn_unused_result, warn 890 // about it. void foo() { strlen("bar"); } should warn. 891 // 892 // Note: If new cases are added here, DiagnoseUnusedExprResult should be 893 // updated to match for QoI. 894 if (FD->getAttr<WarnUnusedResultAttr>() || 895 FD->getAttr<PureAttr>() || FD->getAttr<ConstAttr>()) { 896 Loc = CE->getCallee()->getLocStart(); 897 R1 = CE->getCallee()->getSourceRange(); 898 899 if (unsigned NumArgs = CE->getNumArgs()) 900 R2 = SourceRange(CE->getArg(0)->getLocStart(), 901 CE->getArg(NumArgs-1)->getLocEnd()); 902 return true; 903 } 904 } 905 return false; 906 } 907 908 case CXXTemporaryObjectExprClass: 909 case CXXConstructExprClass: 910 return false; 911 912 case ObjCMessageExprClass: 913 return false; 914 915 case ObjCImplicitSetterGetterRefExprClass: { // Dot syntax for message send. 916#if 0 917 const ObjCImplicitSetterGetterRefExpr *Ref = 918 cast<ObjCImplicitSetterGetterRefExpr>(this); 919 // FIXME: We really want the location of the '.' here. 920 Loc = Ref->getLocation(); 921 R1 = SourceRange(Ref->getLocation(), Ref->getLocation()); 922 if (Ref->getBase()) 923 R2 = Ref->getBase()->getSourceRange(); 924#else 925 Loc = getExprLoc(); 926 R1 = getSourceRange(); 927#endif 928 return true; 929 } 930 case StmtExprClass: { 931 // Statement exprs don't logically have side effects themselves, but are 932 // sometimes used in macros in ways that give them a type that is unused. 933 // For example ({ blah; foo(); }) will end up with a type if foo has a type. 934 // however, if the result of the stmt expr is dead, we don't want to emit a 935 // warning. 936 const CompoundStmt *CS = cast<StmtExpr>(this)->getSubStmt(); 937 if (!CS->body_empty()) 938 if (const Expr *E = dyn_cast<Expr>(CS->body_back())) 939 return E->isUnusedResultAWarning(Loc, R1, R2, Ctx); 940 941 if (getType()->isVoidType()) 942 return false; 943 Loc = cast<StmtExpr>(this)->getLParenLoc(); 944 R1 = getSourceRange(); 945 return true; 946 } 947 case CStyleCastExprClass: 948 // If this is an explicit cast to void, allow it. People do this when they 949 // think they know what they're doing :). 950 if (getType()->isVoidType()) 951 return false; 952 Loc = cast<CStyleCastExpr>(this)->getLParenLoc(); 953 R1 = cast<CStyleCastExpr>(this)->getSubExpr()->getSourceRange(); 954 return true; 955 case CXXFunctionalCastExprClass: { 956 if (getType()->isVoidType()) 957 return false; 958 const CastExpr *CE = cast<CastExpr>(this); 959 960 // If this is a cast to void or a constructor conversion, check the operand. 961 // Otherwise, the result of the cast is unused. 962 if (CE->getCastKind() == CastExpr::CK_ToVoid || 963 CE->getCastKind() == CastExpr::CK_ConstructorConversion) 964 return (cast<CastExpr>(this)->getSubExpr() 965 ->isUnusedResultAWarning(Loc, R1, R2, Ctx)); 966 Loc = cast<CXXFunctionalCastExpr>(this)->getTypeBeginLoc(); 967 R1 = cast<CXXFunctionalCastExpr>(this)->getSubExpr()->getSourceRange(); 968 return true; 969 } 970 971 case ImplicitCastExprClass: 972 // Check the operand, since implicit casts are inserted by Sema 973 return (cast<ImplicitCastExpr>(this) 974 ->getSubExpr()->isUnusedResultAWarning(Loc, R1, R2, Ctx)); 975 976 case CXXDefaultArgExprClass: 977 return (cast<CXXDefaultArgExpr>(this) 978 ->getExpr()->isUnusedResultAWarning(Loc, R1, R2, Ctx)); 979 980 case CXXNewExprClass: 981 // FIXME: In theory, there might be new expressions that don't have side 982 // effects (e.g. a placement new with an uninitialized POD). 983 case CXXDeleteExprClass: 984 return false; 985 case CXXBindTemporaryExprClass: 986 return (cast<CXXBindTemporaryExpr>(this) 987 ->getSubExpr()->isUnusedResultAWarning(Loc, R1, R2, Ctx)); 988 case CXXExprWithTemporariesClass: 989 return (cast<CXXExprWithTemporaries>(this) 990 ->getSubExpr()->isUnusedResultAWarning(Loc, R1, R2, Ctx)); 991 } 992} 993 994/// DeclCanBeLvalue - Determine whether the given declaration can be 995/// an lvalue. This is a helper routine for isLvalue. 996static bool DeclCanBeLvalue(const NamedDecl *Decl, ASTContext &Ctx) { 997 // C++ [temp.param]p6: 998 // A non-type non-reference template-parameter is not an lvalue. 999 if (const NonTypeTemplateParmDecl *NTTParm 1000 = dyn_cast<NonTypeTemplateParmDecl>(Decl)) 1001 return NTTParm->getType()->isReferenceType(); 1002 1003 return isa<VarDecl>(Decl) || isa<FieldDecl>(Decl) || 1004 // C++ 3.10p2: An lvalue refers to an object or function. 1005 (Ctx.getLangOptions().CPlusPlus && 1006 (isa<FunctionDecl>(Decl) || isa<FunctionTemplateDecl>(Decl))); 1007} 1008 1009/// isLvalue - C99 6.3.2.1: an lvalue is an expression with an object type or an 1010/// incomplete type other than void. Nonarray expressions that can be lvalues: 1011/// - name, where name must be a variable 1012/// - e[i] 1013/// - (e), where e must be an lvalue 1014/// - e.name, where e must be an lvalue 1015/// - e->name 1016/// - *e, the type of e cannot be a function type 1017/// - string-constant 1018/// - (__real__ e) and (__imag__ e) where e is an lvalue [GNU extension] 1019/// - reference type [C++ [expr]] 1020/// 1021Expr::isLvalueResult Expr::isLvalue(ASTContext &Ctx) const { 1022 assert(!TR->isReferenceType() && "Expressions can't have reference type."); 1023 1024 isLvalueResult Res = isLvalueInternal(Ctx); 1025 if (Res != LV_Valid || Ctx.getLangOptions().CPlusPlus) 1026 return Res; 1027 1028 // first, check the type (C99 6.3.2.1). Expressions with function 1029 // type in C are not lvalues, but they can be lvalues in C++. 1030 if (TR->isFunctionType() || TR == Ctx.OverloadTy) 1031 return LV_NotObjectType; 1032 1033 // Allow qualified void which is an incomplete type other than void (yuck). 1034 if (TR->isVoidType() && !Ctx.getCanonicalType(TR).hasQualifiers()) 1035 return LV_IncompleteVoidType; 1036 1037 return LV_Valid; 1038} 1039 1040// Check whether the expression can be sanely treated like an l-value 1041Expr::isLvalueResult Expr::isLvalueInternal(ASTContext &Ctx) const { 1042 switch (getStmtClass()) { 1043 case ObjCIsaExprClass: 1044 case StringLiteralClass: // C99 6.5.1p4 1045 case ObjCEncodeExprClass: // @encode behaves like its string in every way. 1046 return LV_Valid; 1047 case ArraySubscriptExprClass: // C99 6.5.3p4 (e1[e2] == (*((e1)+(e2)))) 1048 // For vectors, make sure base is an lvalue (i.e. not a function call). 1049 if (cast<ArraySubscriptExpr>(this)->getBase()->getType()->isVectorType()) 1050 return cast<ArraySubscriptExpr>(this)->getBase()->isLvalue(Ctx); 1051 return LV_Valid; 1052 case DeclRefExprClass: { // C99 6.5.1p2 1053 const NamedDecl *RefdDecl = cast<DeclRefExpr>(this)->getDecl(); 1054 if (DeclCanBeLvalue(RefdDecl, Ctx)) 1055 return LV_Valid; 1056 break; 1057 } 1058 case BlockDeclRefExprClass: { 1059 const BlockDeclRefExpr *BDR = cast<BlockDeclRefExpr>(this); 1060 if (isa<VarDecl>(BDR->getDecl())) 1061 return LV_Valid; 1062 break; 1063 } 1064 case MemberExprClass: { 1065 const MemberExpr *m = cast<MemberExpr>(this); 1066 if (Ctx.getLangOptions().CPlusPlus) { // C++ [expr.ref]p4: 1067 NamedDecl *Member = m->getMemberDecl(); 1068 // C++ [expr.ref]p4: 1069 // If E2 is declared to have type "reference to T", then E1.E2 1070 // is an lvalue. 1071 if (ValueDecl *Value = dyn_cast<ValueDecl>(Member)) 1072 if (Value->getType()->isReferenceType()) 1073 return LV_Valid; 1074 1075 // -- If E2 is a static data member [...] then E1.E2 is an lvalue. 1076 if (isa<VarDecl>(Member) && Member->getDeclContext()->isRecord()) 1077 return LV_Valid; 1078 1079 // -- If E2 is a non-static data member [...]. If E1 is an 1080 // lvalue, then E1.E2 is an lvalue. 1081 if (isa<FieldDecl>(Member)) { 1082 if (m->isArrow()) 1083 return LV_Valid; 1084 return m->getBase()->isLvalue(Ctx); 1085 } 1086 1087 // -- If it refers to a static member function [...], then 1088 // E1.E2 is an lvalue. 1089 // -- Otherwise, if E1.E2 refers to a non-static member 1090 // function [...], then E1.E2 is not an lvalue. 1091 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Member)) 1092 return Method->isStatic()? LV_Valid : LV_MemberFunction; 1093 1094 // -- If E2 is a member enumerator [...], the expression E1.E2 1095 // is not an lvalue. 1096 if (isa<EnumConstantDecl>(Member)) 1097 return LV_InvalidExpression; 1098 1099 // Not an lvalue. 1100 return LV_InvalidExpression; 1101 } 1102 1103 // C99 6.5.2.3p4 1104 if (m->isArrow()) 1105 return LV_Valid; 1106 Expr *BaseExp = m->getBase(); 1107 if (BaseExp->getStmtClass() == ObjCPropertyRefExprClass || 1108 BaseExp->getStmtClass() == ObjCImplicitSetterGetterRefExprClass) 1109 return LV_SubObjCPropertySetting; 1110 return 1111 BaseExp->isLvalue(Ctx); 1112 } 1113 case UnaryOperatorClass: 1114 if (cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::Deref) 1115 return LV_Valid; // C99 6.5.3p4 1116 1117 if (cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::Real || 1118 cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::Imag || 1119 cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::Extension) 1120 return cast<UnaryOperator>(this)->getSubExpr()->isLvalue(Ctx); // GNU. 1121 1122 if (Ctx.getLangOptions().CPlusPlus && // C++ [expr.pre.incr]p1 1123 (cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::PreInc || 1124 cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::PreDec)) 1125 return LV_Valid; 1126 break; 1127 case ImplicitCastExprClass: 1128 if (cast<ImplicitCastExpr>(this)->isLvalueCast()) 1129 return LV_Valid; 1130 1131 // If this is a conversion to a class temporary, make a note of 1132 // that. 1133 if (Ctx.getLangOptions().CPlusPlus && getType()->isRecordType()) 1134 return LV_ClassTemporary; 1135 1136 break; 1137 case ParenExprClass: // C99 6.5.1p5 1138 return cast<ParenExpr>(this)->getSubExpr()->isLvalue(Ctx); 1139 case BinaryOperatorClass: 1140 case CompoundAssignOperatorClass: { 1141 const BinaryOperator *BinOp = cast<BinaryOperator>(this); 1142 1143 if (Ctx.getLangOptions().CPlusPlus && // C++ [expr.comma]p1 1144 BinOp->getOpcode() == BinaryOperator::Comma) 1145 return BinOp->getRHS()->isLvalue(Ctx); 1146 1147 // C++ [expr.mptr.oper]p6 1148 // The result of a .* expression is an lvalue only if its first operand is 1149 // an lvalue and its second operand is a pointer to data member. 1150 if (BinOp->getOpcode() == BinaryOperator::PtrMemD && 1151 !BinOp->getType()->isFunctionType()) 1152 return BinOp->getLHS()->isLvalue(Ctx); 1153 1154 // The result of an ->* expression is an lvalue only if its second operand 1155 // is a pointer to data member. 1156 if (BinOp->getOpcode() == BinaryOperator::PtrMemI && 1157 !BinOp->getType()->isFunctionType()) { 1158 QualType Ty = BinOp->getRHS()->getType(); 1159 if (Ty->isMemberPointerType() && !Ty->isMemberFunctionPointerType()) 1160 return LV_Valid; 1161 } 1162 1163 if (!BinOp->isAssignmentOp()) 1164 return LV_InvalidExpression; 1165 1166 if (Ctx.getLangOptions().CPlusPlus) 1167 // C++ [expr.ass]p1: 1168 // The result of an assignment operation [...] is an lvalue. 1169 return LV_Valid; 1170 1171 1172 // C99 6.5.16: 1173 // An assignment expression [...] is not an lvalue. 1174 return LV_InvalidExpression; 1175 } 1176 case CallExprClass: 1177 case CXXOperatorCallExprClass: 1178 case CXXMemberCallExprClass: { 1179 // C++0x [expr.call]p10 1180 // A function call is an lvalue if and only if the result type 1181 // is an lvalue reference. 1182 QualType ReturnType = cast<CallExpr>(this)->getCallReturnType(); 1183 if (ReturnType->isLValueReferenceType()) 1184 return LV_Valid; 1185 1186 // If the function is returning a class temporary, make a note of 1187 // that. 1188 if (Ctx.getLangOptions().CPlusPlus && ReturnType->isRecordType()) 1189 return LV_ClassTemporary; 1190 1191 break; 1192 } 1193 case CompoundLiteralExprClass: // C99 6.5.2.5p5 1194 // FIXME: Is this what we want in C++? 1195 return LV_Valid; 1196 case ChooseExprClass: 1197 // __builtin_choose_expr is an lvalue if the selected operand is. 1198 return cast<ChooseExpr>(this)->getChosenSubExpr(Ctx)->isLvalue(Ctx); 1199 case ExtVectorElementExprClass: 1200 if (cast<ExtVectorElementExpr>(this)->containsDuplicateElements()) 1201 return LV_DuplicateVectorComponents; 1202 return LV_Valid; 1203 case ObjCIvarRefExprClass: // ObjC instance variables are lvalues. 1204 return LV_Valid; 1205 case ObjCPropertyRefExprClass: // FIXME: check if read-only property. 1206 return LV_Valid; 1207 case ObjCImplicitSetterGetterRefExprClass: // FIXME: check if read-only property. 1208 return LV_Valid; 1209 case PredefinedExprClass: 1210 return LV_Valid; 1211 case UnresolvedLookupExprClass: 1212 return LV_Valid; 1213 case CXXDefaultArgExprClass: 1214 return cast<CXXDefaultArgExpr>(this)->getExpr()->isLvalue(Ctx); 1215 case CStyleCastExprClass: 1216 case CXXFunctionalCastExprClass: 1217 case CXXStaticCastExprClass: 1218 case CXXDynamicCastExprClass: 1219 case CXXReinterpretCastExprClass: 1220 case CXXConstCastExprClass: 1221 // The result of an explicit cast is an lvalue if the type we are 1222 // casting to is an lvalue reference type. See C++ [expr.cast]p1, 1223 // C++ [expr.static.cast]p2, C++ [expr.dynamic.cast]p2, 1224 // C++ [expr.reinterpret.cast]p1, C++ [expr.const.cast]p1. 1225 if (cast<ExplicitCastExpr>(this)->getTypeAsWritten()-> 1226 isLValueReferenceType()) 1227 return LV_Valid; 1228 1229 // If this is a conversion to a class temporary, make a note of 1230 // that. 1231 if (Ctx.getLangOptions().CPlusPlus && 1232 cast<ExplicitCastExpr>(this)->getTypeAsWritten()->isRecordType()) 1233 return LV_ClassTemporary; 1234 1235 break; 1236 case CXXTypeidExprClass: 1237 // C++ 5.2.8p1: The result of a typeid expression is an lvalue of ... 1238 return LV_Valid; 1239 case CXXBindTemporaryExprClass: 1240 return cast<CXXBindTemporaryExpr>(this)->getSubExpr()-> 1241 isLvalueInternal(Ctx); 1242 case CXXBindReferenceExprClass: 1243 // Something that's bound to a reference is always an lvalue. 1244 return LV_Valid; 1245 case ConditionalOperatorClass: { 1246 // Complicated handling is only for C++. 1247 if (!Ctx.getLangOptions().CPlusPlus) 1248 return LV_InvalidExpression; 1249 1250 // Sema should have taken care to ensure that a CXXTemporaryObjectExpr is 1251 // everywhere there's an object converted to an rvalue. Also, any other 1252 // casts should be wrapped by ImplicitCastExprs. There's just the special 1253 // case involving throws to work out. 1254 const ConditionalOperator *Cond = cast<ConditionalOperator>(this); 1255 Expr *True = Cond->getTrueExpr(); 1256 Expr *False = Cond->getFalseExpr(); 1257 // C++0x 5.16p2 1258 // If either the second or the third operand has type (cv) void, [...] 1259 // the result [...] is an rvalue. 1260 if (True->getType()->isVoidType() || False->getType()->isVoidType()) 1261 return LV_InvalidExpression; 1262 1263 // Both sides must be lvalues for the result to be an lvalue. 1264 if (True->isLvalue(Ctx) != LV_Valid || False->isLvalue(Ctx) != LV_Valid) 1265 return LV_InvalidExpression; 1266 1267 // That's it. 1268 return LV_Valid; 1269 } 1270 1271 case Expr::CXXExprWithTemporariesClass: 1272 return cast<CXXExprWithTemporaries>(this)->getSubExpr()->isLvalue(Ctx); 1273 1274 case Expr::ObjCMessageExprClass: 1275 if (const ObjCMethodDecl *Method 1276 = cast<ObjCMessageExpr>(this)->getMethodDecl()) 1277 if (Method->getResultType()->isLValueReferenceType()) 1278 return LV_Valid; 1279 break; 1280 1281 case Expr::CXXConstructExprClass: 1282 case Expr::CXXTemporaryObjectExprClass: 1283 case Expr::CXXZeroInitValueExprClass: 1284 return LV_ClassTemporary; 1285 1286 default: 1287 break; 1288 } 1289 return LV_InvalidExpression; 1290} 1291 1292/// isModifiableLvalue - C99 6.3.2.1: an lvalue that does not have array type, 1293/// does not have an incomplete type, does not have a const-qualified type, and 1294/// if it is a structure or union, does not have any member (including, 1295/// recursively, any member or element of all contained aggregates or unions) 1296/// with a const-qualified type. 1297Expr::isModifiableLvalueResult 1298Expr::isModifiableLvalue(ASTContext &Ctx, SourceLocation *Loc) const { 1299 isLvalueResult lvalResult = isLvalue(Ctx); 1300 1301 switch (lvalResult) { 1302 case LV_Valid: 1303 // C++ 3.10p11: Functions cannot be modified, but pointers to 1304 // functions can be modifiable. 1305 if (Ctx.getLangOptions().CPlusPlus && TR->isFunctionType()) 1306 return MLV_NotObjectType; 1307 break; 1308 1309 case LV_NotObjectType: return MLV_NotObjectType; 1310 case LV_IncompleteVoidType: return MLV_IncompleteVoidType; 1311 case LV_DuplicateVectorComponents: return MLV_DuplicateVectorComponents; 1312 case LV_InvalidExpression: 1313 // If the top level is a C-style cast, and the subexpression is a valid 1314 // lvalue, then this is probably a use of the old-school "cast as lvalue" 1315 // GCC extension. We don't support it, but we want to produce good 1316 // diagnostics when it happens so that the user knows why. 1317 if (const CStyleCastExpr *CE = dyn_cast<CStyleCastExpr>(IgnoreParens())) { 1318 if (CE->getSubExpr()->isLvalue(Ctx) == LV_Valid) { 1319 if (Loc) 1320 *Loc = CE->getLParenLoc(); 1321 return MLV_LValueCast; 1322 } 1323 } 1324 return MLV_InvalidExpression; 1325 case LV_MemberFunction: return MLV_MemberFunction; 1326 case LV_SubObjCPropertySetting: return MLV_SubObjCPropertySetting; 1327 case LV_ClassTemporary: 1328 return MLV_ClassTemporary; 1329 } 1330 1331 // The following is illegal: 1332 // void takeclosure(void (^C)(void)); 1333 // void func() { int x = 1; takeclosure(^{ x = 7; }); } 1334 // 1335 if (const BlockDeclRefExpr *BDR = dyn_cast<BlockDeclRefExpr>(this)) { 1336 if (!BDR->isByRef() && isa<VarDecl>(BDR->getDecl())) 1337 return MLV_NotBlockQualified; 1338 } 1339 1340 // Assigning to an 'implicit' property? 1341 if (const ObjCImplicitSetterGetterRefExpr* Expr = 1342 dyn_cast<ObjCImplicitSetterGetterRefExpr>(this)) { 1343 if (Expr->getSetterMethod() == 0) 1344 return MLV_NoSetterProperty; 1345 } 1346 1347 QualType CT = Ctx.getCanonicalType(getType()); 1348 1349 if (CT.isConstQualified()) 1350 return MLV_ConstQualified; 1351 if (CT->isArrayType()) 1352 return MLV_ArrayType; 1353 if (CT->isIncompleteType()) 1354 return MLV_IncompleteType; 1355 1356 if (const RecordType *r = CT->getAs<RecordType>()) { 1357 if (r->hasConstFields()) 1358 return MLV_ConstQualified; 1359 } 1360 1361 return MLV_Valid; 1362} 1363 1364/// isOBJCGCCandidate - Check if an expression is objc gc'able. 1365/// returns true, if it is; false otherwise. 1366bool Expr::isOBJCGCCandidate(ASTContext &Ctx) const { 1367 switch (getStmtClass()) { 1368 default: 1369 return false; 1370 case ObjCIvarRefExprClass: 1371 return true; 1372 case Expr::UnaryOperatorClass: 1373 return cast<UnaryOperator>(this)->getSubExpr()->isOBJCGCCandidate(Ctx); 1374 case ParenExprClass: 1375 return cast<ParenExpr>(this)->getSubExpr()->isOBJCGCCandidate(Ctx); 1376 case ImplicitCastExprClass: 1377 return cast<ImplicitCastExpr>(this)->getSubExpr()->isOBJCGCCandidate(Ctx); 1378 case CStyleCastExprClass: 1379 return cast<CStyleCastExpr>(this)->getSubExpr()->isOBJCGCCandidate(Ctx); 1380 case DeclRefExprClass: { 1381 const Decl *D = cast<DeclRefExpr>(this)->getDecl(); 1382 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1383 if (VD->hasGlobalStorage()) 1384 return true; 1385 QualType T = VD->getType(); 1386 // dereferencing to a pointer is always a gc'able candidate, 1387 // unless it is __weak. 1388 return T->isPointerType() && 1389 (Ctx.getObjCGCAttrKind(T) != Qualifiers::Weak); 1390 } 1391 return false; 1392 } 1393 case MemberExprClass: { 1394 const MemberExpr *M = cast<MemberExpr>(this); 1395 return M->getBase()->isOBJCGCCandidate(Ctx); 1396 } 1397 case ArraySubscriptExprClass: 1398 return cast<ArraySubscriptExpr>(this)->getBase()->isOBJCGCCandidate(Ctx); 1399 } 1400} 1401Expr* Expr::IgnoreParens() { 1402 Expr* E = this; 1403 while (ParenExpr* P = dyn_cast<ParenExpr>(E)) 1404 E = P->getSubExpr(); 1405 1406 return E; 1407} 1408 1409/// IgnoreParenCasts - Ignore parentheses and casts. Strip off any ParenExpr 1410/// or CastExprs or ImplicitCastExprs, returning their operand. 1411Expr *Expr::IgnoreParenCasts() { 1412 Expr *E = this; 1413 while (true) { 1414 if (ParenExpr *P = dyn_cast<ParenExpr>(E)) 1415 E = P->getSubExpr(); 1416 else if (CastExpr *P = dyn_cast<CastExpr>(E)) 1417 E = P->getSubExpr(); 1418 else 1419 return E; 1420 } 1421} 1422 1423/// IgnoreParenNoopCasts - Ignore parentheses and casts that do not change the 1424/// value (including ptr->int casts of the same size). Strip off any 1425/// ParenExpr or CastExprs, returning their operand. 1426Expr *Expr::IgnoreParenNoopCasts(ASTContext &Ctx) { 1427 Expr *E = this; 1428 while (true) { 1429 if (ParenExpr *P = dyn_cast<ParenExpr>(E)) { 1430 E = P->getSubExpr(); 1431 continue; 1432 } 1433 1434 if (CastExpr *P = dyn_cast<CastExpr>(E)) { 1435 // We ignore integer <-> casts that are of the same width, ptr<->ptr and 1436 // ptr<->int casts of the same width. We also ignore all identify casts. 1437 Expr *SE = P->getSubExpr(); 1438 1439 if (Ctx.hasSameUnqualifiedType(E->getType(), SE->getType())) { 1440 E = SE; 1441 continue; 1442 } 1443 1444 if ((E->getType()->isPointerType() || E->getType()->isIntegralType()) && 1445 (SE->getType()->isPointerType() || SE->getType()->isIntegralType()) && 1446 Ctx.getTypeSize(E->getType()) == Ctx.getTypeSize(SE->getType())) { 1447 E = SE; 1448 continue; 1449 } 1450 } 1451 1452 return E; 1453 } 1454} 1455 1456bool Expr::isDefaultArgument() const { 1457 const Expr *E = this; 1458 while (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) 1459 E = ICE->getSubExprAsWritten(); 1460 1461 return isa<CXXDefaultArgExpr>(E); 1462} 1463 1464/// hasAnyTypeDependentArguments - Determines if any of the expressions 1465/// in Exprs is type-dependent. 1466bool Expr::hasAnyTypeDependentArguments(Expr** Exprs, unsigned NumExprs) { 1467 for (unsigned I = 0; I < NumExprs; ++I) 1468 if (Exprs[I]->isTypeDependent()) 1469 return true; 1470 1471 return false; 1472} 1473 1474/// hasAnyValueDependentArguments - Determines if any of the expressions 1475/// in Exprs is value-dependent. 1476bool Expr::hasAnyValueDependentArguments(Expr** Exprs, unsigned NumExprs) { 1477 for (unsigned I = 0; I < NumExprs; ++I) 1478 if (Exprs[I]->isValueDependent()) 1479 return true; 1480 1481 return false; 1482} 1483 1484bool Expr::isConstantInitializer(ASTContext &Ctx) const { 1485 // This function is attempting whether an expression is an initializer 1486 // which can be evaluated at compile-time. isEvaluatable handles most 1487 // of the cases, but it can't deal with some initializer-specific 1488 // expressions, and it can't deal with aggregates; we deal with those here, 1489 // and fall back to isEvaluatable for the other cases. 1490 1491 // FIXME: This function assumes the variable being assigned to 1492 // isn't a reference type! 1493 1494 switch (getStmtClass()) { 1495 default: break; 1496 case StringLiteralClass: 1497 case ObjCStringLiteralClass: 1498 case ObjCEncodeExprClass: 1499 return true; 1500 case CompoundLiteralExprClass: { 1501 // This handles gcc's extension that allows global initializers like 1502 // "struct x {int x;} x = (struct x) {};". 1503 // FIXME: This accepts other cases it shouldn't! 1504 const Expr *Exp = cast<CompoundLiteralExpr>(this)->getInitializer(); 1505 return Exp->isConstantInitializer(Ctx); 1506 } 1507 case InitListExprClass: { 1508 // FIXME: This doesn't deal with fields with reference types correctly. 1509 // FIXME: This incorrectly allows pointers cast to integers to be assigned 1510 // to bitfields. 1511 const InitListExpr *Exp = cast<InitListExpr>(this); 1512 unsigned numInits = Exp->getNumInits(); 1513 for (unsigned i = 0; i < numInits; i++) { 1514 if (!Exp->getInit(i)->isConstantInitializer(Ctx)) 1515 return false; 1516 } 1517 return true; 1518 } 1519 case ImplicitValueInitExprClass: 1520 return true; 1521 case ParenExprClass: 1522 return cast<ParenExpr>(this)->getSubExpr()->isConstantInitializer(Ctx); 1523 case UnaryOperatorClass: { 1524 const UnaryOperator* Exp = cast<UnaryOperator>(this); 1525 if (Exp->getOpcode() == UnaryOperator::Extension) 1526 return Exp->getSubExpr()->isConstantInitializer(Ctx); 1527 break; 1528 } 1529 case BinaryOperatorClass: { 1530 // Special case &&foo - &&bar. It would be nice to generalize this somehow 1531 // but this handles the common case. 1532 const BinaryOperator *Exp = cast<BinaryOperator>(this); 1533 if (Exp->getOpcode() == BinaryOperator::Sub && 1534 isa<AddrLabelExpr>(Exp->getLHS()->IgnoreParenNoopCasts(Ctx)) && 1535 isa<AddrLabelExpr>(Exp->getRHS()->IgnoreParenNoopCasts(Ctx))) 1536 return true; 1537 break; 1538 } 1539 case ImplicitCastExprClass: 1540 case CStyleCastExprClass: 1541 // Handle casts with a destination that's a struct or union; this 1542 // deals with both the gcc no-op struct cast extension and the 1543 // cast-to-union extension. 1544 if (getType()->isRecordType()) 1545 return cast<CastExpr>(this)->getSubExpr()->isConstantInitializer(Ctx); 1546 1547 // Integer->integer casts can be handled here, which is important for 1548 // things like (int)(&&x-&&y). Scary but true. 1549 if (getType()->isIntegerType() && 1550 cast<CastExpr>(this)->getSubExpr()->getType()->isIntegerType()) 1551 return cast<CastExpr>(this)->getSubExpr()->isConstantInitializer(Ctx); 1552 1553 break; 1554 } 1555 return isEvaluatable(Ctx); 1556} 1557 1558/// isIntegerConstantExpr - this recursive routine will test if an expression is 1559/// an integer constant expression. 1560 1561/// FIXME: Pass up a reason why! Invalid operation in i-c-e, division by zero, 1562/// comma, etc 1563/// 1564/// FIXME: Handle offsetof. Two things to do: Handle GCC's __builtin_offsetof 1565/// to support gcc 4.0+ and handle the idiom GCC recognizes with a null pointer 1566/// cast+dereference. 1567 1568// CheckICE - This function does the fundamental ICE checking: the returned 1569// ICEDiag contains a Val of 0, 1, or 2, and a possibly null SourceLocation. 1570// Note that to reduce code duplication, this helper does no evaluation 1571// itself; the caller checks whether the expression is evaluatable, and 1572// in the rare cases where CheckICE actually cares about the evaluated 1573// value, it calls into Evalute. 1574// 1575// Meanings of Val: 1576// 0: This expression is an ICE if it can be evaluated by Evaluate. 1577// 1: This expression is not an ICE, but if it isn't evaluated, it's 1578// a legal subexpression for an ICE. This return value is used to handle 1579// the comma operator in C99 mode. 1580// 2: This expression is not an ICE, and is not a legal subexpression for one. 1581 1582struct ICEDiag { 1583 unsigned Val; 1584 SourceLocation Loc; 1585 1586 public: 1587 ICEDiag(unsigned v, SourceLocation l) : Val(v), Loc(l) {} 1588 ICEDiag() : Val(0) {} 1589}; 1590 1591ICEDiag NoDiag() { return ICEDiag(); } 1592 1593static ICEDiag CheckEvalInICE(const Expr* E, ASTContext &Ctx) { 1594 Expr::EvalResult EVResult; 1595 if (!E->Evaluate(EVResult, Ctx) || EVResult.HasSideEffects || 1596 !EVResult.Val.isInt()) { 1597 return ICEDiag(2, E->getLocStart()); 1598 } 1599 return NoDiag(); 1600} 1601 1602static ICEDiag CheckICE(const Expr* E, ASTContext &Ctx) { 1603 assert(!E->isValueDependent() && "Should not see value dependent exprs!"); 1604 if (!E->getType()->isIntegralType()) { 1605 return ICEDiag(2, E->getLocStart()); 1606 } 1607 1608 switch (E->getStmtClass()) { 1609#define STMT(Node, Base) case Expr::Node##Class: 1610#define EXPR(Node, Base) 1611#include "clang/AST/StmtNodes.def" 1612 case Expr::PredefinedExprClass: 1613 case Expr::FloatingLiteralClass: 1614 case Expr::ImaginaryLiteralClass: 1615 case Expr::StringLiteralClass: 1616 case Expr::ArraySubscriptExprClass: 1617 case Expr::MemberExprClass: 1618 case Expr::CompoundAssignOperatorClass: 1619 case Expr::CompoundLiteralExprClass: 1620 case Expr::ExtVectorElementExprClass: 1621 case Expr::InitListExprClass: 1622 case Expr::DesignatedInitExprClass: 1623 case Expr::ImplicitValueInitExprClass: 1624 case Expr::ParenListExprClass: 1625 case Expr::VAArgExprClass: 1626 case Expr::AddrLabelExprClass: 1627 case Expr::StmtExprClass: 1628 case Expr::CXXMemberCallExprClass: 1629 case Expr::CXXDynamicCastExprClass: 1630 case Expr::CXXTypeidExprClass: 1631 case Expr::CXXNullPtrLiteralExprClass: 1632 case Expr::CXXThisExprClass: 1633 case Expr::CXXThrowExprClass: 1634 case Expr::CXXNewExprClass: 1635 case Expr::CXXDeleteExprClass: 1636 case Expr::CXXPseudoDestructorExprClass: 1637 case Expr::UnresolvedLookupExprClass: 1638 case Expr::DependentScopeDeclRefExprClass: 1639 case Expr::CXXConstructExprClass: 1640 case Expr::CXXBindTemporaryExprClass: 1641 case Expr::CXXBindReferenceExprClass: 1642 case Expr::CXXExprWithTemporariesClass: 1643 case Expr::CXXTemporaryObjectExprClass: 1644 case Expr::CXXUnresolvedConstructExprClass: 1645 case Expr::CXXDependentScopeMemberExprClass: 1646 case Expr::UnresolvedMemberExprClass: 1647 case Expr::ObjCStringLiteralClass: 1648 case Expr::ObjCEncodeExprClass: 1649 case Expr::ObjCMessageExprClass: 1650 case Expr::ObjCSelectorExprClass: 1651 case Expr::ObjCProtocolExprClass: 1652 case Expr::ObjCIvarRefExprClass: 1653 case Expr::ObjCPropertyRefExprClass: 1654 case Expr::ObjCImplicitSetterGetterRefExprClass: 1655 case Expr::ObjCSuperExprClass: 1656 case Expr::ObjCIsaExprClass: 1657 case Expr::ShuffleVectorExprClass: 1658 case Expr::BlockExprClass: 1659 case Expr::BlockDeclRefExprClass: 1660 case Expr::NoStmtClass: 1661 return ICEDiag(2, E->getLocStart()); 1662 1663 case Expr::GNUNullExprClass: 1664 // GCC considers the GNU __null value to be an integral constant expression. 1665 return NoDiag(); 1666 1667 case Expr::ParenExprClass: 1668 return CheckICE(cast<ParenExpr>(E)->getSubExpr(), Ctx); 1669 case Expr::IntegerLiteralClass: 1670 case Expr::CharacterLiteralClass: 1671 case Expr::CXXBoolLiteralExprClass: 1672 case Expr::CXXZeroInitValueExprClass: 1673 case Expr::TypesCompatibleExprClass: 1674 case Expr::UnaryTypeTraitExprClass: 1675 return NoDiag(); 1676 case Expr::CallExprClass: 1677 case Expr::CXXOperatorCallExprClass: { 1678 const CallExpr *CE = cast<CallExpr>(E); 1679 if (CE->isBuiltinCall(Ctx)) 1680 return CheckEvalInICE(E, Ctx); 1681 return ICEDiag(2, E->getLocStart()); 1682 } 1683 case Expr::DeclRefExprClass: 1684 if (isa<EnumConstantDecl>(cast<DeclRefExpr>(E)->getDecl())) 1685 return NoDiag(); 1686 if (Ctx.getLangOptions().CPlusPlus && 1687 E->getType().getCVRQualifiers() == Qualifiers::Const) { 1688 const NamedDecl *D = cast<DeclRefExpr>(E)->getDecl(); 1689 1690 // Parameter variables are never constants. Without this check, 1691 // getAnyInitializer() can find a default argument, which leads 1692 // to chaos. 1693 if (isa<ParmVarDecl>(D)) 1694 return ICEDiag(2, cast<DeclRefExpr>(E)->getLocation()); 1695 1696 // C++ 7.1.5.1p2 1697 // A variable of non-volatile const-qualified integral or enumeration 1698 // type initialized by an ICE can be used in ICEs. 1699 if (const VarDecl *Dcl = dyn_cast<VarDecl>(D)) { 1700 Qualifiers Quals = Ctx.getCanonicalType(Dcl->getType()).getQualifiers(); 1701 if (Quals.hasVolatile() || !Quals.hasConst()) 1702 return ICEDiag(2, cast<DeclRefExpr>(E)->getLocation()); 1703 1704 // Look for a declaration of this variable that has an initializer. 1705 const VarDecl *ID = 0; 1706 const Expr *Init = Dcl->getAnyInitializer(ID); 1707 if (Init) { 1708 if (ID->isInitKnownICE()) { 1709 // We have already checked whether this subexpression is an 1710 // integral constant expression. 1711 if (ID->isInitICE()) 1712 return NoDiag(); 1713 else 1714 return ICEDiag(2, cast<DeclRefExpr>(E)->getLocation()); 1715 } 1716 1717 // It's an ICE whether or not the definition we found is 1718 // out-of-line. See DR 721 and the discussion in Clang PR 1719 // 6206 for details. 1720 1721 if (Dcl->isCheckingICE()) { 1722 return ICEDiag(2, cast<DeclRefExpr>(E)->getLocation()); 1723 } 1724 1725 Dcl->setCheckingICE(); 1726 ICEDiag Result = CheckICE(Init, Ctx); 1727 // Cache the result of the ICE test. 1728 Dcl->setInitKnownICE(Result.Val == 0); 1729 return Result; 1730 } 1731 } 1732 } 1733 return ICEDiag(2, E->getLocStart()); 1734 case Expr::UnaryOperatorClass: { 1735 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1736 switch (Exp->getOpcode()) { 1737 case UnaryOperator::PostInc: 1738 case UnaryOperator::PostDec: 1739 case UnaryOperator::PreInc: 1740 case UnaryOperator::PreDec: 1741 case UnaryOperator::AddrOf: 1742 case UnaryOperator::Deref: 1743 return ICEDiag(2, E->getLocStart()); 1744 1745 case UnaryOperator::Extension: 1746 case UnaryOperator::LNot: 1747 case UnaryOperator::Plus: 1748 case UnaryOperator::Minus: 1749 case UnaryOperator::Not: 1750 case UnaryOperator::Real: 1751 case UnaryOperator::Imag: 1752 return CheckICE(Exp->getSubExpr(), Ctx); 1753 case UnaryOperator::OffsetOf: 1754 // Note that per C99, offsetof must be an ICE. And AFAIK, using 1755 // Evaluate matches the proposed gcc behavior for cases like 1756 // "offsetof(struct s{int x[4];}, x[!.0])". This doesn't affect 1757 // compliance: we should warn earlier for offsetof expressions with 1758 // array subscripts that aren't ICEs, and if the array subscripts 1759 // are ICEs, the value of the offsetof must be an integer constant. 1760 return CheckEvalInICE(E, Ctx); 1761 } 1762 } 1763 case Expr::SizeOfAlignOfExprClass: { 1764 const SizeOfAlignOfExpr *Exp = cast<SizeOfAlignOfExpr>(E); 1765 if (Exp->isSizeOf() && Exp->getTypeOfArgument()->isVariableArrayType()) 1766 return ICEDiag(2, E->getLocStart()); 1767 return NoDiag(); 1768 } 1769 case Expr::BinaryOperatorClass: { 1770 const BinaryOperator *Exp = cast<BinaryOperator>(E); 1771 switch (Exp->getOpcode()) { 1772 case BinaryOperator::PtrMemD: 1773 case BinaryOperator::PtrMemI: 1774 case BinaryOperator::Assign: 1775 case BinaryOperator::MulAssign: 1776 case BinaryOperator::DivAssign: 1777 case BinaryOperator::RemAssign: 1778 case BinaryOperator::AddAssign: 1779 case BinaryOperator::SubAssign: 1780 case BinaryOperator::ShlAssign: 1781 case BinaryOperator::ShrAssign: 1782 case BinaryOperator::AndAssign: 1783 case BinaryOperator::XorAssign: 1784 case BinaryOperator::OrAssign: 1785 return ICEDiag(2, E->getLocStart()); 1786 1787 case BinaryOperator::Mul: 1788 case BinaryOperator::Div: 1789 case BinaryOperator::Rem: 1790 case BinaryOperator::Add: 1791 case BinaryOperator::Sub: 1792 case BinaryOperator::Shl: 1793 case BinaryOperator::Shr: 1794 case BinaryOperator::LT: 1795 case BinaryOperator::GT: 1796 case BinaryOperator::LE: 1797 case BinaryOperator::GE: 1798 case BinaryOperator::EQ: 1799 case BinaryOperator::NE: 1800 case BinaryOperator::And: 1801 case BinaryOperator::Xor: 1802 case BinaryOperator::Or: 1803 case BinaryOperator::Comma: { 1804 ICEDiag LHSResult = CheckICE(Exp->getLHS(), Ctx); 1805 ICEDiag RHSResult = CheckICE(Exp->getRHS(), Ctx); 1806 if (Exp->getOpcode() == BinaryOperator::Div || 1807 Exp->getOpcode() == BinaryOperator::Rem) { 1808 // Evaluate gives an error for undefined Div/Rem, so make sure 1809 // we don't evaluate one. 1810 if (LHSResult.Val != 2 && RHSResult.Val != 2) { 1811 llvm::APSInt REval = Exp->getRHS()->EvaluateAsInt(Ctx); 1812 if (REval == 0) 1813 return ICEDiag(1, E->getLocStart()); 1814 if (REval.isSigned() && REval.isAllOnesValue()) { 1815 llvm::APSInt LEval = Exp->getLHS()->EvaluateAsInt(Ctx); 1816 if (LEval.isMinSignedValue()) 1817 return ICEDiag(1, E->getLocStart()); 1818 } 1819 } 1820 } 1821 if (Exp->getOpcode() == BinaryOperator::Comma) { 1822 if (Ctx.getLangOptions().C99) { 1823 // C99 6.6p3 introduces a strange edge case: comma can be in an ICE 1824 // if it isn't evaluated. 1825 if (LHSResult.Val == 0 && RHSResult.Val == 0) 1826 return ICEDiag(1, E->getLocStart()); 1827 } else { 1828 // In both C89 and C++, commas in ICEs are illegal. 1829 return ICEDiag(2, E->getLocStart()); 1830 } 1831 } 1832 if (LHSResult.Val >= RHSResult.Val) 1833 return LHSResult; 1834 return RHSResult; 1835 } 1836 case BinaryOperator::LAnd: 1837 case BinaryOperator::LOr: { 1838 ICEDiag LHSResult = CheckICE(Exp->getLHS(), Ctx); 1839 ICEDiag RHSResult = CheckICE(Exp->getRHS(), Ctx); 1840 if (LHSResult.Val == 0 && RHSResult.Val == 1) { 1841 // Rare case where the RHS has a comma "side-effect"; we need 1842 // to actually check the condition to see whether the side 1843 // with the comma is evaluated. 1844 if ((Exp->getOpcode() == BinaryOperator::LAnd) != 1845 (Exp->getLHS()->EvaluateAsInt(Ctx) == 0)) 1846 return RHSResult; 1847 return NoDiag(); 1848 } 1849 1850 if (LHSResult.Val >= RHSResult.Val) 1851 return LHSResult; 1852 return RHSResult; 1853 } 1854 } 1855 } 1856 case Expr::ImplicitCastExprClass: 1857 case Expr::CStyleCastExprClass: 1858 case Expr::CXXFunctionalCastExprClass: 1859 case Expr::CXXNamedCastExprClass: 1860 case Expr::CXXStaticCastExprClass: 1861 case Expr::CXXReinterpretCastExprClass: 1862 case Expr::CXXConstCastExprClass: { 1863 const Expr *SubExpr = cast<CastExpr>(E)->getSubExpr(); 1864 if (SubExpr->getType()->isIntegralType()) 1865 return CheckICE(SubExpr, Ctx); 1866 if (isa<FloatingLiteral>(SubExpr->IgnoreParens())) 1867 return NoDiag(); 1868 return ICEDiag(2, E->getLocStart()); 1869 } 1870 case Expr::ConditionalOperatorClass: { 1871 const ConditionalOperator *Exp = cast<ConditionalOperator>(E); 1872 // If the condition (ignoring parens) is a __builtin_constant_p call, 1873 // then only the true side is actually considered in an integer constant 1874 // expression, and it is fully evaluated. This is an important GNU 1875 // extension. See GCC PR38377 for discussion. 1876 if (const CallExpr *CallCE = dyn_cast<CallExpr>(Exp->getCond()->IgnoreParenCasts())) 1877 if (CallCE->isBuiltinCall(Ctx) == Builtin::BI__builtin_constant_p) { 1878 Expr::EvalResult EVResult; 1879 if (!E->Evaluate(EVResult, Ctx) || EVResult.HasSideEffects || 1880 !EVResult.Val.isInt()) { 1881 return ICEDiag(2, E->getLocStart()); 1882 } 1883 return NoDiag(); 1884 } 1885 ICEDiag CondResult = CheckICE(Exp->getCond(), Ctx); 1886 ICEDiag TrueResult = CheckICE(Exp->getTrueExpr(), Ctx); 1887 ICEDiag FalseResult = CheckICE(Exp->getFalseExpr(), Ctx); 1888 if (CondResult.Val == 2) 1889 return CondResult; 1890 if (TrueResult.Val == 2) 1891 return TrueResult; 1892 if (FalseResult.Val == 2) 1893 return FalseResult; 1894 if (CondResult.Val == 1) 1895 return CondResult; 1896 if (TrueResult.Val == 0 && FalseResult.Val == 0) 1897 return NoDiag(); 1898 // Rare case where the diagnostics depend on which side is evaluated 1899 // Note that if we get here, CondResult is 0, and at least one of 1900 // TrueResult and FalseResult is non-zero. 1901 if (Exp->getCond()->EvaluateAsInt(Ctx) == 0) { 1902 return FalseResult; 1903 } 1904 return TrueResult; 1905 } 1906 case Expr::CXXDefaultArgExprClass: 1907 return CheckICE(cast<CXXDefaultArgExpr>(E)->getExpr(), Ctx); 1908 case Expr::ChooseExprClass: { 1909 return CheckICE(cast<ChooseExpr>(E)->getChosenSubExpr(Ctx), Ctx); 1910 } 1911 } 1912 1913 // Silence a GCC warning 1914 return ICEDiag(2, E->getLocStart()); 1915} 1916 1917bool Expr::isIntegerConstantExpr(llvm::APSInt &Result, ASTContext &Ctx, 1918 SourceLocation *Loc, bool isEvaluated) const { 1919 ICEDiag d = CheckICE(this, Ctx); 1920 if (d.Val != 0) { 1921 if (Loc) *Loc = d.Loc; 1922 return false; 1923 } 1924 EvalResult EvalResult; 1925 if (!Evaluate(EvalResult, Ctx)) 1926 llvm_unreachable("ICE cannot be evaluated!"); 1927 assert(!EvalResult.HasSideEffects && "ICE with side effects!"); 1928 assert(EvalResult.Val.isInt() && "ICE that isn't integer!"); 1929 Result = EvalResult.Val.getInt(); 1930 return true; 1931} 1932 1933/// isNullPointerConstant - C99 6.3.2.3p3 - Return true if this is either an 1934/// integer constant expression with the value zero, or if this is one that is 1935/// cast to void*. 1936bool Expr::isNullPointerConstant(ASTContext &Ctx, 1937 NullPointerConstantValueDependence NPC) const { 1938 if (isValueDependent()) { 1939 switch (NPC) { 1940 case NPC_NeverValueDependent: 1941 assert(false && "Unexpected value dependent expression!"); 1942 // If the unthinkable happens, fall through to the safest alternative. 1943 1944 case NPC_ValueDependentIsNull: 1945 return isTypeDependent() || getType()->isIntegralType(); 1946 1947 case NPC_ValueDependentIsNotNull: 1948 return false; 1949 } 1950 } 1951 1952 // Strip off a cast to void*, if it exists. Except in C++. 1953 if (const ExplicitCastExpr *CE = dyn_cast<ExplicitCastExpr>(this)) { 1954 if (!Ctx.getLangOptions().CPlusPlus) { 1955 // Check that it is a cast to void*. 1956 if (const PointerType *PT = CE->getType()->getAs<PointerType>()) { 1957 QualType Pointee = PT->getPointeeType(); 1958 if (!Pointee.hasQualifiers() && 1959 Pointee->isVoidType() && // to void* 1960 CE->getSubExpr()->getType()->isIntegerType()) // from int. 1961 return CE->getSubExpr()->isNullPointerConstant(Ctx, NPC); 1962 } 1963 } 1964 } else if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(this)) { 1965 // Ignore the ImplicitCastExpr type entirely. 1966 return ICE->getSubExpr()->isNullPointerConstant(Ctx, NPC); 1967 } else if (const ParenExpr *PE = dyn_cast<ParenExpr>(this)) { 1968 // Accept ((void*)0) as a null pointer constant, as many other 1969 // implementations do. 1970 return PE->getSubExpr()->isNullPointerConstant(Ctx, NPC); 1971 } else if (const CXXDefaultArgExpr *DefaultArg 1972 = dyn_cast<CXXDefaultArgExpr>(this)) { 1973 // See through default argument expressions 1974 return DefaultArg->getExpr()->isNullPointerConstant(Ctx, NPC); 1975 } else if (isa<GNUNullExpr>(this)) { 1976 // The GNU __null extension is always a null pointer constant. 1977 return true; 1978 } 1979 1980 // C++0x nullptr_t is always a null pointer constant. 1981 if (getType()->isNullPtrType()) 1982 return true; 1983 1984 // This expression must be an integer type. 1985 if (!getType()->isIntegerType() || 1986 (Ctx.getLangOptions().CPlusPlus && getType()->isEnumeralType())) 1987 return false; 1988 1989 // If we have an integer constant expression, we need to *evaluate* it and 1990 // test for the value 0. 1991 llvm::APSInt Result; 1992 return isIntegerConstantExpr(Result, Ctx) && Result == 0; 1993} 1994 1995FieldDecl *Expr::getBitField() { 1996 Expr *E = this->IgnoreParens(); 1997 1998 while (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) { 1999 if (ICE->isLvalueCast() && ICE->getCastKind() == CastExpr::CK_NoOp) 2000 E = ICE->getSubExpr()->IgnoreParens(); 2001 else 2002 break; 2003 } 2004 2005 if (MemberExpr *MemRef = dyn_cast<MemberExpr>(E)) 2006 if (FieldDecl *Field = dyn_cast<FieldDecl>(MemRef->getMemberDecl())) 2007 if (Field->isBitField()) 2008 return Field; 2009 2010 if (BinaryOperator *BinOp = dyn_cast<BinaryOperator>(E)) 2011 if (BinOp->isAssignmentOp() && BinOp->getLHS()) 2012 return BinOp->getLHS()->getBitField(); 2013 2014 return 0; 2015} 2016 2017bool Expr::refersToVectorElement() const { 2018 const Expr *E = this->IgnoreParens(); 2019 2020 while (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) { 2021 if (ICE->isLvalueCast() && ICE->getCastKind() == CastExpr::CK_NoOp) 2022 E = ICE->getSubExpr()->IgnoreParens(); 2023 else 2024 break; 2025 } 2026 2027 if (const ArraySubscriptExpr *ASE = dyn_cast<ArraySubscriptExpr>(E)) 2028 return ASE->getBase()->getType()->isVectorType(); 2029 2030 if (isa<ExtVectorElementExpr>(E)) 2031 return true; 2032 2033 return false; 2034} 2035 2036/// isArrow - Return true if the base expression is a pointer to vector, 2037/// return false if the base expression is a vector. 2038bool ExtVectorElementExpr::isArrow() const { 2039 return getBase()->getType()->isPointerType(); 2040} 2041 2042unsigned ExtVectorElementExpr::getNumElements() const { 2043 if (const VectorType *VT = getType()->getAs<VectorType>()) 2044 return VT->getNumElements(); 2045 return 1; 2046} 2047 2048/// containsDuplicateElements - Return true if any element access is repeated. 2049bool ExtVectorElementExpr::containsDuplicateElements() const { 2050 // FIXME: Refactor this code to an accessor on the AST node which returns the 2051 // "type" of component access, and share with code below and in Sema. 2052 llvm::StringRef Comp = Accessor->getName(); 2053 2054 // Halving swizzles do not contain duplicate elements. 2055 if (Comp == "hi" || Comp == "lo" || Comp == "even" || Comp == "odd") 2056 return false; 2057 2058 // Advance past s-char prefix on hex swizzles. 2059 if (Comp[0] == 's' || Comp[0] == 'S') 2060 Comp = Comp.substr(1); 2061 2062 for (unsigned i = 0, e = Comp.size(); i != e; ++i) 2063 if (Comp.substr(i + 1).find(Comp[i]) != llvm::StringRef::npos) 2064 return true; 2065 2066 return false; 2067} 2068 2069/// getEncodedElementAccess - We encode the fields as a llvm ConstantArray. 2070void ExtVectorElementExpr::getEncodedElementAccess( 2071 llvm::SmallVectorImpl<unsigned> &Elts) const { 2072 llvm::StringRef Comp = Accessor->getName(); 2073 if (Comp[0] == 's' || Comp[0] == 'S') 2074 Comp = Comp.substr(1); 2075 2076 bool isHi = Comp == "hi"; 2077 bool isLo = Comp == "lo"; 2078 bool isEven = Comp == "even"; 2079 bool isOdd = Comp == "odd"; 2080 2081 for (unsigned i = 0, e = getNumElements(); i != e; ++i) { 2082 uint64_t Index; 2083 2084 if (isHi) 2085 Index = e + i; 2086 else if (isLo) 2087 Index = i; 2088 else if (isEven) 2089 Index = 2 * i; 2090 else if (isOdd) 2091 Index = 2 * i + 1; 2092 else 2093 Index = ExtVectorType::getAccessorIdx(Comp[i]); 2094 2095 Elts.push_back(Index); 2096 } 2097} 2098 2099// constructor for instance messages. 2100ObjCMessageExpr::ObjCMessageExpr(ASTContext &C, Expr *receiver, 2101 Selector selInfo, 2102 QualType retType, ObjCMethodDecl *mproto, 2103 SourceLocation LBrac, SourceLocation RBrac, 2104 Expr **ArgExprs, unsigned nargs) 2105 : Expr(ObjCMessageExprClass, retType, false, false), SelName(selInfo), 2106 MethodProto(mproto) { 2107 NumArgs = nargs; 2108 SubExprs = new (C) Stmt*[NumArgs+1]; 2109 SubExprs[RECEIVER] = receiver; 2110 if (NumArgs) { 2111 for (unsigned i = 0; i != NumArgs; ++i) 2112 SubExprs[i+ARGS_START] = static_cast<Expr *>(ArgExprs[i]); 2113 } 2114 LBracloc = LBrac; 2115 RBracloc = RBrac; 2116} 2117 2118// constructor for class messages. 2119// FIXME: clsName should be typed to ObjCInterfaceType 2120ObjCMessageExpr::ObjCMessageExpr(ASTContext &C, IdentifierInfo *clsName, 2121 SourceLocation clsNameLoc, Selector selInfo, 2122 QualType retType, ObjCMethodDecl *mproto, 2123 SourceLocation LBrac, SourceLocation RBrac, 2124 Expr **ArgExprs, unsigned nargs) 2125 : Expr(ObjCMessageExprClass, retType, false, false), ClassNameLoc(clsNameLoc), 2126 SelName(selInfo), MethodProto(mproto) { 2127 NumArgs = nargs; 2128 SubExprs = new (C) Stmt*[NumArgs+1]; 2129 SubExprs[RECEIVER] = (Expr*) ((uintptr_t) clsName | IsClsMethDeclUnknown); 2130 if (NumArgs) { 2131 for (unsigned i = 0; i != NumArgs; ++i) 2132 SubExprs[i+ARGS_START] = static_cast<Expr *>(ArgExprs[i]); 2133 } 2134 LBracloc = LBrac; 2135 RBracloc = RBrac; 2136} 2137 2138// constructor for class messages. 2139ObjCMessageExpr::ObjCMessageExpr(ASTContext &C, ObjCInterfaceDecl *cls, 2140 SourceLocation clsNameLoc, Selector selInfo, 2141 QualType retType, 2142 ObjCMethodDecl *mproto, SourceLocation LBrac, 2143 SourceLocation RBrac, Expr **ArgExprs, 2144 unsigned nargs) 2145 : Expr(ObjCMessageExprClass, retType, false, false), ClassNameLoc(clsNameLoc), 2146 SelName(selInfo), MethodProto(mproto) 2147{ 2148 NumArgs = nargs; 2149 SubExprs = new (C) Stmt*[NumArgs+1]; 2150 SubExprs[RECEIVER] = (Expr*) ((uintptr_t) cls | IsClsMethDeclKnown); 2151 if (NumArgs) { 2152 for (unsigned i = 0; i != NumArgs; ++i) 2153 SubExprs[i+ARGS_START] = static_cast<Expr *>(ArgExprs[i]); 2154 } 2155 LBracloc = LBrac; 2156 RBracloc = RBrac; 2157} 2158 2159ObjCMessageExpr::ClassInfo ObjCMessageExpr::getClassInfo() const { 2160 uintptr_t x = (uintptr_t) SubExprs[RECEIVER]; 2161 switch (x & Flags) { 2162 default: 2163 assert(false && "Invalid ObjCMessageExpr."); 2164 case IsInstMeth: 2165 return ClassInfo(0, 0, SourceLocation()); 2166 case IsClsMethDeclUnknown: 2167 return ClassInfo(0, (IdentifierInfo*) (x & ~Flags), ClassNameLoc); 2168 case IsClsMethDeclKnown: { 2169 ObjCInterfaceDecl* D = (ObjCInterfaceDecl*) (x & ~Flags); 2170 return ClassInfo(D, D->getIdentifier(), ClassNameLoc); 2171 } 2172 } 2173} 2174 2175void ObjCMessageExpr::setClassInfo(const ObjCMessageExpr::ClassInfo &CI) { 2176 if (CI.Decl == 0 && CI.Name == 0) { 2177 SubExprs[RECEIVER] = (Expr*)((uintptr_t)0 | IsInstMeth); 2178 return; 2179 } 2180 2181 if (CI.Decl == 0) 2182 SubExprs[RECEIVER] = (Expr*)((uintptr_t)CI.Name | IsClsMethDeclUnknown); 2183 else 2184 SubExprs[RECEIVER] = (Expr*)((uintptr_t)CI.Decl | IsClsMethDeclKnown); 2185 ClassNameLoc = CI.Loc; 2186} 2187 2188void ObjCMessageExpr::DoDestroy(ASTContext &C) { 2189 DestroyChildren(C); 2190 if (SubExprs) 2191 C.Deallocate(SubExprs); 2192 this->~ObjCMessageExpr(); 2193 C.Deallocate((void*) this); 2194} 2195 2196bool ChooseExpr::isConditionTrue(ASTContext &C) const { 2197 return getCond()->EvaluateAsInt(C) != 0; 2198} 2199 2200void ShuffleVectorExpr::setExprs(ASTContext &C, Expr ** Exprs, 2201 unsigned NumExprs) { 2202 if (SubExprs) C.Deallocate(SubExprs); 2203 2204 SubExprs = new (C) Stmt* [NumExprs]; 2205 this->NumExprs = NumExprs; 2206 memcpy(SubExprs, Exprs, sizeof(Expr *) * NumExprs); 2207} 2208 2209void ShuffleVectorExpr::DoDestroy(ASTContext& C) { 2210 DestroyChildren(C); 2211 if (SubExprs) C.Deallocate(SubExprs); 2212 this->~ShuffleVectorExpr(); 2213 C.Deallocate(this); 2214} 2215 2216void SizeOfAlignOfExpr::DoDestroy(ASTContext& C) { 2217 // Override default behavior of traversing children. If this has a type 2218 // operand and the type is a variable-length array, the child iteration 2219 // will iterate over the size expression. However, this expression belongs 2220 // to the type, not to this, so we don't want to delete it. 2221 // We still want to delete this expression. 2222 if (isArgumentType()) { 2223 this->~SizeOfAlignOfExpr(); 2224 C.Deallocate(this); 2225 } 2226 else 2227 Expr::DoDestroy(C); 2228} 2229 2230//===----------------------------------------------------------------------===// 2231// DesignatedInitExpr 2232//===----------------------------------------------------------------------===// 2233 2234IdentifierInfo *DesignatedInitExpr::Designator::getFieldName() { 2235 assert(Kind == FieldDesignator && "Only valid on a field designator"); 2236 if (Field.NameOrField & 0x01) 2237 return reinterpret_cast<IdentifierInfo *>(Field.NameOrField&~0x01); 2238 else 2239 return getField()->getIdentifier(); 2240} 2241 2242DesignatedInitExpr::DesignatedInitExpr(ASTContext &C, QualType Ty, 2243 unsigned NumDesignators, 2244 const Designator *Designators, 2245 SourceLocation EqualOrColonLoc, 2246 bool GNUSyntax, 2247 Expr **IndexExprs, 2248 unsigned NumIndexExprs, 2249 Expr *Init) 2250 : Expr(DesignatedInitExprClass, Ty, 2251 Init->isTypeDependent(), Init->isValueDependent()), 2252 EqualOrColonLoc(EqualOrColonLoc), GNUSyntax(GNUSyntax), 2253 NumDesignators(NumDesignators), NumSubExprs(NumIndexExprs + 1) { 2254 this->Designators = new (C) Designator[NumDesignators]; 2255 2256 // Record the initializer itself. 2257 child_iterator Child = child_begin(); 2258 *Child++ = Init; 2259 2260 // Copy the designators and their subexpressions, computing 2261 // value-dependence along the way. 2262 unsigned IndexIdx = 0; 2263 for (unsigned I = 0; I != NumDesignators; ++I) { 2264 this->Designators[I] = Designators[I]; 2265 2266 if (this->Designators[I].isArrayDesignator()) { 2267 // Compute type- and value-dependence. 2268 Expr *Index = IndexExprs[IndexIdx]; 2269 ValueDependent = ValueDependent || 2270 Index->isTypeDependent() || Index->isValueDependent(); 2271 2272 // Copy the index expressions into permanent storage. 2273 *Child++ = IndexExprs[IndexIdx++]; 2274 } else if (this->Designators[I].isArrayRangeDesignator()) { 2275 // Compute type- and value-dependence. 2276 Expr *Start = IndexExprs[IndexIdx]; 2277 Expr *End = IndexExprs[IndexIdx + 1]; 2278 ValueDependent = ValueDependent || 2279 Start->isTypeDependent() || Start->isValueDependent() || 2280 End->isTypeDependent() || End->isValueDependent(); 2281 2282 // Copy the start/end expressions into permanent storage. 2283 *Child++ = IndexExprs[IndexIdx++]; 2284 *Child++ = IndexExprs[IndexIdx++]; 2285 } 2286 } 2287 2288 assert(IndexIdx == NumIndexExprs && "Wrong number of index expressions"); 2289} 2290 2291DesignatedInitExpr * 2292DesignatedInitExpr::Create(ASTContext &C, Designator *Designators, 2293 unsigned NumDesignators, 2294 Expr **IndexExprs, unsigned NumIndexExprs, 2295 SourceLocation ColonOrEqualLoc, 2296 bool UsesColonSyntax, Expr *Init) { 2297 void *Mem = C.Allocate(sizeof(DesignatedInitExpr) + 2298 sizeof(Stmt *) * (NumIndexExprs + 1), 8); 2299 return new (Mem) DesignatedInitExpr(C, C.VoidTy, NumDesignators, Designators, 2300 ColonOrEqualLoc, UsesColonSyntax, 2301 IndexExprs, NumIndexExprs, Init); 2302} 2303 2304DesignatedInitExpr *DesignatedInitExpr::CreateEmpty(ASTContext &C, 2305 unsigned NumIndexExprs) { 2306 void *Mem = C.Allocate(sizeof(DesignatedInitExpr) + 2307 sizeof(Stmt *) * (NumIndexExprs + 1), 8); 2308 return new (Mem) DesignatedInitExpr(NumIndexExprs + 1); 2309} 2310 2311void DesignatedInitExpr::setDesignators(ASTContext &C, 2312 const Designator *Desigs, 2313 unsigned NumDesigs) { 2314 DestroyDesignators(C); 2315 2316 Designators = new (C) Designator[NumDesigs]; 2317 NumDesignators = NumDesigs; 2318 for (unsigned I = 0; I != NumDesigs; ++I) 2319 Designators[I] = Desigs[I]; 2320} 2321 2322SourceRange DesignatedInitExpr::getSourceRange() const { 2323 SourceLocation StartLoc; 2324 Designator &First = 2325 *const_cast<DesignatedInitExpr*>(this)->designators_begin(); 2326 if (First.isFieldDesignator()) { 2327 if (GNUSyntax) 2328 StartLoc = SourceLocation::getFromRawEncoding(First.Field.FieldLoc); 2329 else 2330 StartLoc = SourceLocation::getFromRawEncoding(First.Field.DotLoc); 2331 } else 2332 StartLoc = 2333 SourceLocation::getFromRawEncoding(First.ArrayOrRange.LBracketLoc); 2334 return SourceRange(StartLoc, getInit()->getSourceRange().getEnd()); 2335} 2336 2337Expr *DesignatedInitExpr::getArrayIndex(const Designator& D) { 2338 assert(D.Kind == Designator::ArrayDesignator && "Requires array designator"); 2339 char* Ptr = static_cast<char*>(static_cast<void *>(this)); 2340 Ptr += sizeof(DesignatedInitExpr); 2341 Stmt **SubExprs = reinterpret_cast<Stmt**>(reinterpret_cast<void**>(Ptr)); 2342 return cast<Expr>(*(SubExprs + D.ArrayOrRange.Index + 1)); 2343} 2344 2345Expr *DesignatedInitExpr::getArrayRangeStart(const Designator& D) { 2346 assert(D.Kind == Designator::ArrayRangeDesignator && 2347 "Requires array range designator"); 2348 char* Ptr = static_cast<char*>(static_cast<void *>(this)); 2349 Ptr += sizeof(DesignatedInitExpr); 2350 Stmt **SubExprs = reinterpret_cast<Stmt**>(reinterpret_cast<void**>(Ptr)); 2351 return cast<Expr>(*(SubExprs + D.ArrayOrRange.Index + 1)); 2352} 2353 2354Expr *DesignatedInitExpr::getArrayRangeEnd(const Designator& D) { 2355 assert(D.Kind == Designator::ArrayRangeDesignator && 2356 "Requires array range designator"); 2357 char* Ptr = static_cast<char*>(static_cast<void *>(this)); 2358 Ptr += sizeof(DesignatedInitExpr); 2359 Stmt **SubExprs = reinterpret_cast<Stmt**>(reinterpret_cast<void**>(Ptr)); 2360 return cast<Expr>(*(SubExprs + D.ArrayOrRange.Index + 2)); 2361} 2362 2363/// \brief Replaces the designator at index @p Idx with the series 2364/// of designators in [First, Last). 2365void DesignatedInitExpr::ExpandDesignator(ASTContext &C, unsigned Idx, 2366 const Designator *First, 2367 const Designator *Last) { 2368 unsigned NumNewDesignators = Last - First; 2369 if (NumNewDesignators == 0) { 2370 std::copy_backward(Designators + Idx + 1, 2371 Designators + NumDesignators, 2372 Designators + Idx); 2373 --NumNewDesignators; 2374 return; 2375 } else if (NumNewDesignators == 1) { 2376 Designators[Idx] = *First; 2377 return; 2378 } 2379 2380 Designator *NewDesignators 2381 = new (C) Designator[NumDesignators - 1 + NumNewDesignators]; 2382 std::copy(Designators, Designators + Idx, NewDesignators); 2383 std::copy(First, Last, NewDesignators + Idx); 2384 std::copy(Designators + Idx + 1, Designators + NumDesignators, 2385 NewDesignators + Idx + NumNewDesignators); 2386 DestroyDesignators(C); 2387 Designators = NewDesignators; 2388 NumDesignators = NumDesignators - 1 + NumNewDesignators; 2389} 2390 2391void DesignatedInitExpr::DoDestroy(ASTContext &C) { 2392 DestroyDesignators(C); 2393 Expr::DoDestroy(C); 2394} 2395 2396void DesignatedInitExpr::DestroyDesignators(ASTContext &C) { 2397 for (unsigned I = 0; I != NumDesignators; ++I) 2398 Designators[I].~Designator(); 2399 C.Deallocate(Designators); 2400 Designators = 0; 2401} 2402 2403ParenListExpr::ParenListExpr(ASTContext& C, SourceLocation lparenloc, 2404 Expr **exprs, unsigned nexprs, 2405 SourceLocation rparenloc) 2406: Expr(ParenListExprClass, QualType(), 2407 hasAnyTypeDependentArguments(exprs, nexprs), 2408 hasAnyValueDependentArguments(exprs, nexprs)), 2409 NumExprs(nexprs), LParenLoc(lparenloc), RParenLoc(rparenloc) { 2410 2411 Exprs = new (C) Stmt*[nexprs]; 2412 for (unsigned i = 0; i != nexprs; ++i) 2413 Exprs[i] = exprs[i]; 2414} 2415 2416void ParenListExpr::DoDestroy(ASTContext& C) { 2417 DestroyChildren(C); 2418 if (Exprs) C.Deallocate(Exprs); 2419 this->~ParenListExpr(); 2420 C.Deallocate(this); 2421} 2422 2423//===----------------------------------------------------------------------===// 2424// ExprIterator. 2425//===----------------------------------------------------------------------===// 2426 2427Expr* ExprIterator::operator[](size_t idx) { return cast<Expr>(I[idx]); } 2428Expr* ExprIterator::operator*() const { return cast<Expr>(*I); } 2429Expr* ExprIterator::operator->() const { return cast<Expr>(*I); } 2430const Expr* ConstExprIterator::operator[](size_t idx) const { 2431 return cast<Expr>(I[idx]); 2432} 2433const Expr* ConstExprIterator::operator*() const { return cast<Expr>(*I); } 2434const Expr* ConstExprIterator::operator->() const { return cast<Expr>(*I); } 2435 2436//===----------------------------------------------------------------------===// 2437// Child Iterators for iterating over subexpressions/substatements 2438//===----------------------------------------------------------------------===// 2439 2440// DeclRefExpr 2441Stmt::child_iterator DeclRefExpr::child_begin() { return child_iterator(); } 2442Stmt::child_iterator DeclRefExpr::child_end() { return child_iterator(); } 2443 2444// ObjCIvarRefExpr 2445Stmt::child_iterator ObjCIvarRefExpr::child_begin() { return &Base; } 2446Stmt::child_iterator ObjCIvarRefExpr::child_end() { return &Base+1; } 2447 2448// ObjCPropertyRefExpr 2449Stmt::child_iterator ObjCPropertyRefExpr::child_begin() { return &Base; } 2450Stmt::child_iterator ObjCPropertyRefExpr::child_end() { return &Base+1; } 2451 2452// ObjCImplicitSetterGetterRefExpr 2453Stmt::child_iterator ObjCImplicitSetterGetterRefExpr::child_begin() { 2454 return &Base; 2455} 2456Stmt::child_iterator ObjCImplicitSetterGetterRefExpr::child_end() { 2457 return &Base+1; 2458} 2459 2460// ObjCSuperExpr 2461Stmt::child_iterator ObjCSuperExpr::child_begin() { return child_iterator(); } 2462Stmt::child_iterator ObjCSuperExpr::child_end() { return child_iterator(); } 2463 2464// ObjCIsaExpr 2465Stmt::child_iterator ObjCIsaExpr::child_begin() { return &Base; } 2466Stmt::child_iterator ObjCIsaExpr::child_end() { return &Base+1; } 2467 2468// PredefinedExpr 2469Stmt::child_iterator PredefinedExpr::child_begin() { return child_iterator(); } 2470Stmt::child_iterator PredefinedExpr::child_end() { return child_iterator(); } 2471 2472// IntegerLiteral 2473Stmt::child_iterator IntegerLiteral::child_begin() { return child_iterator(); } 2474Stmt::child_iterator IntegerLiteral::child_end() { return child_iterator(); } 2475 2476// CharacterLiteral 2477Stmt::child_iterator CharacterLiteral::child_begin() { return child_iterator();} 2478Stmt::child_iterator CharacterLiteral::child_end() { return child_iterator(); } 2479 2480// FloatingLiteral 2481Stmt::child_iterator FloatingLiteral::child_begin() { return child_iterator(); } 2482Stmt::child_iterator FloatingLiteral::child_end() { return child_iterator(); } 2483 2484// ImaginaryLiteral 2485Stmt::child_iterator ImaginaryLiteral::child_begin() { return &Val; } 2486Stmt::child_iterator ImaginaryLiteral::child_end() { return &Val+1; } 2487 2488// StringLiteral 2489Stmt::child_iterator StringLiteral::child_begin() { return child_iterator(); } 2490Stmt::child_iterator StringLiteral::child_end() { return child_iterator(); } 2491 2492// ParenExpr 2493Stmt::child_iterator ParenExpr::child_begin() { return &Val; } 2494Stmt::child_iterator ParenExpr::child_end() { return &Val+1; } 2495 2496// UnaryOperator 2497Stmt::child_iterator UnaryOperator::child_begin() { return &Val; } 2498Stmt::child_iterator UnaryOperator::child_end() { return &Val+1; } 2499 2500// SizeOfAlignOfExpr 2501Stmt::child_iterator SizeOfAlignOfExpr::child_begin() { 2502 // If this is of a type and the type is a VLA type (and not a typedef), the 2503 // size expression of the VLA needs to be treated as an executable expression. 2504 // Why isn't this weirdness documented better in StmtIterator? 2505 if (isArgumentType()) { 2506 if (VariableArrayType* T = dyn_cast<VariableArrayType>( 2507 getArgumentType().getTypePtr())) 2508 return child_iterator(T); 2509 return child_iterator(); 2510 } 2511 return child_iterator(&Argument.Ex); 2512} 2513Stmt::child_iterator SizeOfAlignOfExpr::child_end() { 2514 if (isArgumentType()) 2515 return child_iterator(); 2516 return child_iterator(&Argument.Ex + 1); 2517} 2518 2519// ArraySubscriptExpr 2520Stmt::child_iterator ArraySubscriptExpr::child_begin() { 2521 return &SubExprs[0]; 2522} 2523Stmt::child_iterator ArraySubscriptExpr::child_end() { 2524 return &SubExprs[0]+END_EXPR; 2525} 2526 2527// CallExpr 2528Stmt::child_iterator CallExpr::child_begin() { 2529 return &SubExprs[0]; 2530} 2531Stmt::child_iterator CallExpr::child_end() { 2532 return &SubExprs[0]+NumArgs+ARGS_START; 2533} 2534 2535// MemberExpr 2536Stmt::child_iterator MemberExpr::child_begin() { return &Base; } 2537Stmt::child_iterator MemberExpr::child_end() { return &Base+1; } 2538 2539// ExtVectorElementExpr 2540Stmt::child_iterator ExtVectorElementExpr::child_begin() { return &Base; } 2541Stmt::child_iterator ExtVectorElementExpr::child_end() { return &Base+1; } 2542 2543// CompoundLiteralExpr 2544Stmt::child_iterator CompoundLiteralExpr::child_begin() { return &Init; } 2545Stmt::child_iterator CompoundLiteralExpr::child_end() { return &Init+1; } 2546 2547// CastExpr 2548Stmt::child_iterator CastExpr::child_begin() { return &Op; } 2549Stmt::child_iterator CastExpr::child_end() { return &Op+1; } 2550 2551// BinaryOperator 2552Stmt::child_iterator BinaryOperator::child_begin() { 2553 return &SubExprs[0]; 2554} 2555Stmt::child_iterator BinaryOperator::child_end() { 2556 return &SubExprs[0]+END_EXPR; 2557} 2558 2559// ConditionalOperator 2560Stmt::child_iterator ConditionalOperator::child_begin() { 2561 return &SubExprs[0]; 2562} 2563Stmt::child_iterator ConditionalOperator::child_end() { 2564 return &SubExprs[0]+END_EXPR; 2565} 2566 2567// AddrLabelExpr 2568Stmt::child_iterator AddrLabelExpr::child_begin() { return child_iterator(); } 2569Stmt::child_iterator AddrLabelExpr::child_end() { return child_iterator(); } 2570 2571// StmtExpr 2572Stmt::child_iterator StmtExpr::child_begin() { return &SubStmt; } 2573Stmt::child_iterator StmtExpr::child_end() { return &SubStmt+1; } 2574 2575// TypesCompatibleExpr 2576Stmt::child_iterator TypesCompatibleExpr::child_begin() { 2577 return child_iterator(); 2578} 2579 2580Stmt::child_iterator TypesCompatibleExpr::child_end() { 2581 return child_iterator(); 2582} 2583 2584// ChooseExpr 2585Stmt::child_iterator ChooseExpr::child_begin() { return &SubExprs[0]; } 2586Stmt::child_iterator ChooseExpr::child_end() { return &SubExprs[0]+END_EXPR; } 2587 2588// GNUNullExpr 2589Stmt::child_iterator GNUNullExpr::child_begin() { return child_iterator(); } 2590Stmt::child_iterator GNUNullExpr::child_end() { return child_iterator(); } 2591 2592// ShuffleVectorExpr 2593Stmt::child_iterator ShuffleVectorExpr::child_begin() { 2594 return &SubExprs[0]; 2595} 2596Stmt::child_iterator ShuffleVectorExpr::child_end() { 2597 return &SubExprs[0]+NumExprs; 2598} 2599 2600// VAArgExpr 2601Stmt::child_iterator VAArgExpr::child_begin() { return &Val; } 2602Stmt::child_iterator VAArgExpr::child_end() { return &Val+1; } 2603 2604// InitListExpr 2605Stmt::child_iterator InitListExpr::child_begin() { 2606 return InitExprs.size() ? &InitExprs[0] : 0; 2607} 2608Stmt::child_iterator InitListExpr::child_end() { 2609 return InitExprs.size() ? &InitExprs[0] + InitExprs.size() : 0; 2610} 2611 2612// DesignatedInitExpr 2613Stmt::child_iterator DesignatedInitExpr::child_begin() { 2614 char* Ptr = static_cast<char*>(static_cast<void *>(this)); 2615 Ptr += sizeof(DesignatedInitExpr); 2616 return reinterpret_cast<Stmt**>(reinterpret_cast<void**>(Ptr)); 2617} 2618Stmt::child_iterator DesignatedInitExpr::child_end() { 2619 return child_iterator(&*child_begin() + NumSubExprs); 2620} 2621 2622// ImplicitValueInitExpr 2623Stmt::child_iterator ImplicitValueInitExpr::child_begin() { 2624 return child_iterator(); 2625} 2626 2627Stmt::child_iterator ImplicitValueInitExpr::child_end() { 2628 return child_iterator(); 2629} 2630 2631// ParenListExpr 2632Stmt::child_iterator ParenListExpr::child_begin() { 2633 return &Exprs[0]; 2634} 2635Stmt::child_iterator ParenListExpr::child_end() { 2636 return &Exprs[0]+NumExprs; 2637} 2638 2639// ObjCStringLiteral 2640Stmt::child_iterator ObjCStringLiteral::child_begin() { 2641 return &String; 2642} 2643Stmt::child_iterator ObjCStringLiteral::child_end() { 2644 return &String+1; 2645} 2646 2647// ObjCEncodeExpr 2648Stmt::child_iterator ObjCEncodeExpr::child_begin() { return child_iterator(); } 2649Stmt::child_iterator ObjCEncodeExpr::child_end() { return child_iterator(); } 2650 2651// ObjCSelectorExpr 2652Stmt::child_iterator ObjCSelectorExpr::child_begin() { 2653 return child_iterator(); 2654} 2655Stmt::child_iterator ObjCSelectorExpr::child_end() { 2656 return child_iterator(); 2657} 2658 2659// ObjCProtocolExpr 2660Stmt::child_iterator ObjCProtocolExpr::child_begin() { 2661 return child_iterator(); 2662} 2663Stmt::child_iterator ObjCProtocolExpr::child_end() { 2664 return child_iterator(); 2665} 2666 2667// ObjCMessageExpr 2668Stmt::child_iterator ObjCMessageExpr::child_begin() { 2669 return getReceiver() ? &SubExprs[0] : &SubExprs[0] + ARGS_START; 2670} 2671Stmt::child_iterator ObjCMessageExpr::child_end() { 2672 return &SubExprs[0]+ARGS_START+getNumArgs(); 2673} 2674 2675// Blocks 2676Stmt::child_iterator BlockExpr::child_begin() { return child_iterator(); } 2677Stmt::child_iterator BlockExpr::child_end() { return child_iterator(); } 2678 2679Stmt::child_iterator BlockDeclRefExpr::child_begin() { return child_iterator();} 2680Stmt::child_iterator BlockDeclRefExpr::child_end() { return child_iterator(); } 2681