Expr.cpp revision 9f9269e810bfe9aea0a57b09250be215808fc1a2
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 Policy.SuppressTagKind = true; 185 186 std::string Proto = FD->getQualifiedNameAsString(Policy); 187 188 const FunctionType *AFT = FD->getType()->getAs<FunctionType>(); 189 const FunctionProtoType *FT = 0; 190 if (FD->hasWrittenPrototype()) 191 FT = dyn_cast<FunctionProtoType>(AFT); 192 193 Proto += "("; 194 if (FT) { 195 llvm::raw_string_ostream POut(Proto); 196 for (unsigned i = 0, e = FD->getNumParams(); i != e; ++i) { 197 if (i) POut << ", "; 198 std::string Param; 199 FD->getParamDecl(i)->getType().getAsStringInternal(Param, Policy); 200 POut << Param; 201 } 202 203 if (FT->isVariadic()) { 204 if (FD->getNumParams()) POut << ", "; 205 POut << "..."; 206 } 207 } 208 Proto += ")"; 209 210 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) { 211 Qualifiers ThisQuals = Qualifiers::fromCVRMask(MD->getTypeQualifiers()); 212 if (ThisQuals.hasConst()) 213 Proto += " const"; 214 if (ThisQuals.hasVolatile()) 215 Proto += " volatile"; 216 } 217 218 if (!isa<CXXConstructorDecl>(FD) && !isa<CXXDestructorDecl>(FD)) 219 AFT->getResultType().getAsStringInternal(Proto, Policy); 220 221 Out << Proto; 222 223 Out.flush(); 224 return Name.str().str(); 225 } 226 if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(CurrentDecl)) { 227 llvm::SmallString<256> Name; 228 llvm::raw_svector_ostream Out(Name); 229 Out << (MD->isInstanceMethod() ? '-' : '+'); 230 Out << '['; 231 Out << MD->getClassInterface()->getNameAsString(); 232 if (const ObjCCategoryImplDecl *CID = 233 dyn_cast<ObjCCategoryImplDecl>(MD->getDeclContext())) { 234 Out << '('; 235 Out << CID->getNameAsString(); 236 Out << ')'; 237 } 238 Out << ' '; 239 Out << MD->getSelector().getAsString(); 240 Out << ']'; 241 242 Out.flush(); 243 return Name.str().str(); 244 } 245 if (isa<TranslationUnitDecl>(CurrentDecl) && IT == PrettyFunction) { 246 // __PRETTY_FUNCTION__ -> "top level", the others produce an empty string. 247 return "top level"; 248 } 249 return ""; 250} 251 252/// getValueAsApproximateDouble - This returns the value as an inaccurate 253/// double. Note that this may cause loss of precision, but is useful for 254/// debugging dumps, etc. 255double FloatingLiteral::getValueAsApproximateDouble() const { 256 llvm::APFloat V = getValue(); 257 bool ignored; 258 V.convert(llvm::APFloat::IEEEdouble, llvm::APFloat::rmNearestTiesToEven, 259 &ignored); 260 return V.convertToDouble(); 261} 262 263StringLiteral *StringLiteral::Create(ASTContext &C, const char *StrData, 264 unsigned ByteLength, bool Wide, 265 QualType Ty, 266 const SourceLocation *Loc, 267 unsigned NumStrs) { 268 // Allocate enough space for the StringLiteral plus an array of locations for 269 // any concatenated string tokens. 270 void *Mem = C.Allocate(sizeof(StringLiteral)+ 271 sizeof(SourceLocation)*(NumStrs-1), 272 llvm::alignof<StringLiteral>()); 273 StringLiteral *SL = new (Mem) StringLiteral(Ty); 274 275 // OPTIMIZE: could allocate this appended to the StringLiteral. 276 char *AStrData = new (C, 1) char[ByteLength]; 277 memcpy(AStrData, StrData, ByteLength); 278 SL->StrData = AStrData; 279 SL->ByteLength = ByteLength; 280 SL->IsWide = Wide; 281 SL->TokLocs[0] = Loc[0]; 282 SL->NumConcatenated = NumStrs; 283 284 if (NumStrs != 1) 285 memcpy(&SL->TokLocs[1], Loc+1, sizeof(SourceLocation)*(NumStrs-1)); 286 return SL; 287} 288 289StringLiteral *StringLiteral::CreateEmpty(ASTContext &C, unsigned NumStrs) { 290 void *Mem = C.Allocate(sizeof(StringLiteral)+ 291 sizeof(SourceLocation)*(NumStrs-1), 292 llvm::alignof<StringLiteral>()); 293 StringLiteral *SL = new (Mem) StringLiteral(QualType()); 294 SL->StrData = 0; 295 SL->ByteLength = 0; 296 SL->NumConcatenated = NumStrs; 297 return SL; 298} 299 300void StringLiteral::DoDestroy(ASTContext &C) { 301 C.Deallocate(const_cast<char*>(StrData)); 302 Expr::DoDestroy(C); 303} 304 305void StringLiteral::setString(ASTContext &C, llvm::StringRef Str) { 306 if (StrData) 307 C.Deallocate(const_cast<char*>(StrData)); 308 309 char *AStrData = new (C, 1) char[Str.size()]; 310 memcpy(AStrData, Str.data(), Str.size()); 311 StrData = AStrData; 312 ByteLength = Str.size(); 313} 314 315/// getOpcodeStr - Turn an Opcode enum value into the punctuation char it 316/// corresponds to, e.g. "sizeof" or "[pre]++". 317const char *UnaryOperator::getOpcodeStr(Opcode Op) { 318 switch (Op) { 319 default: assert(0 && "Unknown unary operator"); 320 case PostInc: return "++"; 321 case PostDec: return "--"; 322 case PreInc: return "++"; 323 case PreDec: return "--"; 324 case AddrOf: return "&"; 325 case Deref: return "*"; 326 case Plus: return "+"; 327 case Minus: return "-"; 328 case Not: return "~"; 329 case LNot: return "!"; 330 case Real: return "__real"; 331 case Imag: return "__imag"; 332 case Extension: return "__extension__"; 333 case OffsetOf: return "__builtin_offsetof"; 334 } 335} 336 337UnaryOperator::Opcode 338UnaryOperator::getOverloadedOpcode(OverloadedOperatorKind OO, bool Postfix) { 339 switch (OO) { 340 default: assert(false && "No unary operator for overloaded function"); 341 case OO_PlusPlus: return Postfix ? PostInc : PreInc; 342 case OO_MinusMinus: return Postfix ? PostDec : PreDec; 343 case OO_Amp: return AddrOf; 344 case OO_Star: return Deref; 345 case OO_Plus: return Plus; 346 case OO_Minus: return Minus; 347 case OO_Tilde: return Not; 348 case OO_Exclaim: return LNot; 349 } 350} 351 352OverloadedOperatorKind UnaryOperator::getOverloadedOperator(Opcode Opc) { 353 switch (Opc) { 354 case PostInc: case PreInc: return OO_PlusPlus; 355 case PostDec: case PreDec: return OO_MinusMinus; 356 case AddrOf: return OO_Amp; 357 case Deref: return OO_Star; 358 case Plus: return OO_Plus; 359 case Minus: return OO_Minus; 360 case Not: return OO_Tilde; 361 case LNot: return OO_Exclaim; 362 default: return OO_None; 363 } 364} 365 366 367//===----------------------------------------------------------------------===// 368// Postfix Operators. 369//===----------------------------------------------------------------------===// 370 371CallExpr::CallExpr(ASTContext& C, StmtClass SC, Expr *fn, Expr **args, 372 unsigned numargs, QualType t, SourceLocation rparenloc) 373 : Expr(SC, t, 374 fn->isTypeDependent() || hasAnyTypeDependentArguments(args, numargs), 375 fn->isValueDependent() || hasAnyValueDependentArguments(args,numargs)), 376 NumArgs(numargs) { 377 378 SubExprs = new (C) Stmt*[numargs+1]; 379 SubExprs[FN] = fn; 380 for (unsigned i = 0; i != numargs; ++i) 381 SubExprs[i+ARGS_START] = args[i]; 382 383 RParenLoc = rparenloc; 384} 385 386CallExpr::CallExpr(ASTContext& C, Expr *fn, Expr **args, unsigned numargs, 387 QualType t, SourceLocation rparenloc) 388 : Expr(CallExprClass, t, 389 fn->isTypeDependent() || hasAnyTypeDependentArguments(args, numargs), 390 fn->isValueDependent() || hasAnyValueDependentArguments(args,numargs)), 391 NumArgs(numargs) { 392 393 SubExprs = new (C) Stmt*[numargs+1]; 394 SubExprs[FN] = fn; 395 for (unsigned i = 0; i != numargs; ++i) 396 SubExprs[i+ARGS_START] = args[i]; 397 398 RParenLoc = rparenloc; 399} 400 401CallExpr::CallExpr(ASTContext &C, StmtClass SC, EmptyShell Empty) 402 : Expr(SC, Empty), SubExprs(0), NumArgs(0) { 403 SubExprs = new (C) Stmt*[1]; 404} 405 406void CallExpr::DoDestroy(ASTContext& C) { 407 DestroyChildren(C); 408 if (SubExprs) C.Deallocate(SubExprs); 409 this->~CallExpr(); 410 C.Deallocate(this); 411} 412 413Decl *CallExpr::getCalleeDecl() { 414 Expr *CEE = getCallee()->IgnoreParenCasts(); 415 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) 416 return DRE->getDecl(); 417 if (MemberExpr *ME = dyn_cast<MemberExpr>(CEE)) 418 return ME->getMemberDecl(); 419 420 return 0; 421} 422 423FunctionDecl *CallExpr::getDirectCallee() { 424 return dyn_cast_or_null<FunctionDecl>(getCalleeDecl()); 425} 426 427/// setNumArgs - This changes the number of arguments present in this call. 428/// Any orphaned expressions are deleted by this, and any new operands are set 429/// to null. 430void CallExpr::setNumArgs(ASTContext& C, unsigned NumArgs) { 431 // No change, just return. 432 if (NumArgs == getNumArgs()) return; 433 434 // If shrinking # arguments, just delete the extras and forgot them. 435 if (NumArgs < getNumArgs()) { 436 for (unsigned i = NumArgs, e = getNumArgs(); i != e; ++i) 437 getArg(i)->Destroy(C); 438 this->NumArgs = NumArgs; 439 return; 440 } 441 442 // Otherwise, we are growing the # arguments. New an bigger argument array. 443 Stmt **NewSubExprs = new (C) Stmt*[NumArgs+1]; 444 // Copy over args. 445 for (unsigned i = 0; i != getNumArgs()+ARGS_START; ++i) 446 NewSubExprs[i] = SubExprs[i]; 447 // Null out new args. 448 for (unsigned i = getNumArgs()+ARGS_START; i != NumArgs+ARGS_START; ++i) 449 NewSubExprs[i] = 0; 450 451 if (SubExprs) C.Deallocate(SubExprs); 452 SubExprs = NewSubExprs; 453 this->NumArgs = NumArgs; 454} 455 456/// isBuiltinCall - If this is a call to a builtin, return the builtin ID. If 457/// not, return 0. 458unsigned CallExpr::isBuiltinCall(ASTContext &Context) const { 459 // All simple function calls (e.g. func()) are implicitly cast to pointer to 460 // function. As a result, we try and obtain the DeclRefExpr from the 461 // ImplicitCastExpr. 462 const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(getCallee()); 463 if (!ICE) // FIXME: deal with more complex calls (e.g. (func)(), (*func)()). 464 return 0; 465 466 const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ICE->getSubExpr()); 467 if (!DRE) 468 return 0; 469 470 const FunctionDecl *FDecl = dyn_cast<FunctionDecl>(DRE->getDecl()); 471 if (!FDecl) 472 return 0; 473 474 if (!FDecl->getIdentifier()) 475 return 0; 476 477 return FDecl->getBuiltinID(); 478} 479 480QualType CallExpr::getCallReturnType() const { 481 QualType CalleeType = getCallee()->getType(); 482 if (const PointerType *FnTypePtr = CalleeType->getAs<PointerType>()) 483 CalleeType = FnTypePtr->getPointeeType(); 484 else if (const BlockPointerType *BPT = CalleeType->getAs<BlockPointerType>()) 485 CalleeType = BPT->getPointeeType(); 486 487 const FunctionType *FnType = CalleeType->getAs<FunctionType>(); 488 return FnType->getResultType(); 489} 490 491MemberExpr::MemberExpr(Expr *base, bool isarrow, NestedNameSpecifier *qual, 492 SourceRange qualrange, ValueDecl *memberdecl, 493 SourceLocation l, const TemplateArgumentListInfo *targs, 494 QualType ty) 495 : Expr(MemberExprClass, ty, 496 base->isTypeDependent() || (qual && qual->isDependent()), 497 base->isValueDependent() || (qual && qual->isDependent())), 498 Base(base), MemberDecl(memberdecl), MemberLoc(l), IsArrow(isarrow), 499 HasQualifier(qual != 0), HasExplicitTemplateArgumentList(targs) { 500 // Initialize the qualifier, if any. 501 if (HasQualifier) { 502 NameQualifier *NQ = getMemberQualifier(); 503 NQ->NNS = qual; 504 NQ->Range = qualrange; 505 } 506 507 // Initialize the explicit template argument list, if any. 508 if (targs) 509 getExplicitTemplateArgumentList()->initializeFrom(*targs); 510} 511 512MemberExpr *MemberExpr::Create(ASTContext &C, Expr *base, bool isarrow, 513 NestedNameSpecifier *qual, 514 SourceRange qualrange, 515 ValueDecl *memberdecl, 516 SourceLocation l, 517 const TemplateArgumentListInfo *targs, 518 QualType ty) { 519 std::size_t Size = sizeof(MemberExpr); 520 if (qual != 0) 521 Size += sizeof(NameQualifier); 522 523 if (targs) 524 Size += ExplicitTemplateArgumentList::sizeFor(*targs); 525 526 void *Mem = C.Allocate(Size, llvm::alignof<MemberExpr>()); 527 return new (Mem) MemberExpr(base, isarrow, qual, qualrange, memberdecl, l, 528 targs, ty); 529} 530 531const char *CastExpr::getCastKindName() const { 532 switch (getCastKind()) { 533 case CastExpr::CK_Unknown: 534 return "Unknown"; 535 case CastExpr::CK_BitCast: 536 return "BitCast"; 537 case CastExpr::CK_NoOp: 538 return "NoOp"; 539 case CastExpr::CK_BaseToDerived: 540 return "BaseToDerived"; 541 case CastExpr::CK_DerivedToBase: 542 return "DerivedToBase"; 543 case CastExpr::CK_Dynamic: 544 return "Dynamic"; 545 case CastExpr::CK_ToUnion: 546 return "ToUnion"; 547 case CastExpr::CK_ArrayToPointerDecay: 548 return "ArrayToPointerDecay"; 549 case CastExpr::CK_FunctionToPointerDecay: 550 return "FunctionToPointerDecay"; 551 case CastExpr::CK_NullToMemberPointer: 552 return "NullToMemberPointer"; 553 case CastExpr::CK_BaseToDerivedMemberPointer: 554 return "BaseToDerivedMemberPointer"; 555 case CastExpr::CK_DerivedToBaseMemberPointer: 556 return "DerivedToBaseMemberPointer"; 557 case CastExpr::CK_UserDefinedConversion: 558 return "UserDefinedConversion"; 559 case CastExpr::CK_ConstructorConversion: 560 return "ConstructorConversion"; 561 case CastExpr::CK_IntegralToPointer: 562 return "IntegralToPointer"; 563 case CastExpr::CK_PointerToIntegral: 564 return "PointerToIntegral"; 565 case CastExpr::CK_ToVoid: 566 return "ToVoid"; 567 case CastExpr::CK_VectorSplat: 568 return "VectorSplat"; 569 case CastExpr::CK_IntegralCast: 570 return "IntegralCast"; 571 case CastExpr::CK_IntegralToFloating: 572 return "IntegralToFloating"; 573 case CastExpr::CK_FloatingToIntegral: 574 return "FloatingToIntegral"; 575 case CastExpr::CK_FloatingCast: 576 return "FloatingCast"; 577 case CastExpr::CK_MemberPointerToBoolean: 578 return "MemberPointerToBoolean"; 579 case CastExpr::CK_AnyPointerToObjCPointerCast: 580 return "AnyPointerToObjCPointerCast"; 581 case CastExpr::CK_AnyPointerToBlockPointerCast: 582 return "AnyPointerToBlockPointerCast"; 583 } 584 585 assert(0 && "Unhandled cast kind!"); 586 return 0; 587} 588 589Expr *CastExpr::getSubExprAsWritten() { 590 Expr *SubExpr = 0; 591 CastExpr *E = this; 592 do { 593 SubExpr = E->getSubExpr(); 594 595 // Skip any temporary bindings; they're implicit. 596 if (CXXBindTemporaryExpr *Binder = dyn_cast<CXXBindTemporaryExpr>(SubExpr)) 597 SubExpr = Binder->getSubExpr(); 598 599 // Conversions by constructor and conversion functions have a 600 // subexpression describing the call; strip it off. 601 if (E->getCastKind() == CastExpr::CK_ConstructorConversion) 602 SubExpr = cast<CXXConstructExpr>(SubExpr)->getArg(0); 603 else if (E->getCastKind() == CastExpr::CK_UserDefinedConversion) 604 SubExpr = cast<CXXMemberCallExpr>(SubExpr)->getImplicitObjectArgument(); 605 606 // If the subexpression we're left with is an implicit cast, look 607 // through that, too. 608 } while ((E = dyn_cast<ImplicitCastExpr>(SubExpr))); 609 610 return SubExpr; 611} 612 613/// getOpcodeStr - Turn an Opcode enum value into the punctuation char it 614/// corresponds to, e.g. "<<=". 615const char *BinaryOperator::getOpcodeStr(Opcode Op) { 616 switch (Op) { 617 case PtrMemD: return ".*"; 618 case PtrMemI: return "->*"; 619 case Mul: return "*"; 620 case Div: return "/"; 621 case Rem: return "%"; 622 case Add: return "+"; 623 case Sub: return "-"; 624 case Shl: return "<<"; 625 case Shr: return ">>"; 626 case LT: return "<"; 627 case GT: return ">"; 628 case LE: return "<="; 629 case GE: return ">="; 630 case EQ: return "=="; 631 case NE: return "!="; 632 case And: return "&"; 633 case Xor: return "^"; 634 case Or: return "|"; 635 case LAnd: return "&&"; 636 case LOr: return "||"; 637 case Assign: return "="; 638 case MulAssign: return "*="; 639 case DivAssign: return "/="; 640 case RemAssign: return "%="; 641 case AddAssign: return "+="; 642 case SubAssign: return "-="; 643 case ShlAssign: return "<<="; 644 case ShrAssign: return ">>="; 645 case AndAssign: return "&="; 646 case XorAssign: return "^="; 647 case OrAssign: return "|="; 648 case Comma: return ","; 649 } 650 651 return ""; 652} 653 654BinaryOperator::Opcode 655BinaryOperator::getOverloadedOpcode(OverloadedOperatorKind OO) { 656 switch (OO) { 657 default: assert(false && "Not an overloadable binary operator"); 658 case OO_Plus: return Add; 659 case OO_Minus: return Sub; 660 case OO_Star: return Mul; 661 case OO_Slash: return Div; 662 case OO_Percent: return Rem; 663 case OO_Caret: return Xor; 664 case OO_Amp: return And; 665 case OO_Pipe: return Or; 666 case OO_Equal: return Assign; 667 case OO_Less: return LT; 668 case OO_Greater: return GT; 669 case OO_PlusEqual: return AddAssign; 670 case OO_MinusEqual: return SubAssign; 671 case OO_StarEqual: return MulAssign; 672 case OO_SlashEqual: return DivAssign; 673 case OO_PercentEqual: return RemAssign; 674 case OO_CaretEqual: return XorAssign; 675 case OO_AmpEqual: return AndAssign; 676 case OO_PipeEqual: return OrAssign; 677 case OO_LessLess: return Shl; 678 case OO_GreaterGreater: return Shr; 679 case OO_LessLessEqual: return ShlAssign; 680 case OO_GreaterGreaterEqual: return ShrAssign; 681 case OO_EqualEqual: return EQ; 682 case OO_ExclaimEqual: return NE; 683 case OO_LessEqual: return LE; 684 case OO_GreaterEqual: return GE; 685 case OO_AmpAmp: return LAnd; 686 case OO_PipePipe: return LOr; 687 case OO_Comma: return Comma; 688 case OO_ArrowStar: return PtrMemI; 689 } 690} 691 692OverloadedOperatorKind BinaryOperator::getOverloadedOperator(Opcode Opc) { 693 static const OverloadedOperatorKind OverOps[] = { 694 /* .* Cannot be overloaded */OO_None, OO_ArrowStar, 695 OO_Star, OO_Slash, OO_Percent, 696 OO_Plus, OO_Minus, 697 OO_LessLess, OO_GreaterGreater, 698 OO_Less, OO_Greater, OO_LessEqual, OO_GreaterEqual, 699 OO_EqualEqual, OO_ExclaimEqual, 700 OO_Amp, 701 OO_Caret, 702 OO_Pipe, 703 OO_AmpAmp, 704 OO_PipePipe, 705 OO_Equal, OO_StarEqual, 706 OO_SlashEqual, OO_PercentEqual, 707 OO_PlusEqual, OO_MinusEqual, 708 OO_LessLessEqual, OO_GreaterGreaterEqual, 709 OO_AmpEqual, OO_CaretEqual, 710 OO_PipeEqual, 711 OO_Comma 712 }; 713 return OverOps[Opc]; 714} 715 716InitListExpr::InitListExpr(ASTContext &C, SourceLocation lbraceloc, 717 Expr **initExprs, unsigned numInits, 718 SourceLocation rbraceloc) 719 : Expr(InitListExprClass, QualType(), false, false), 720 InitExprs(0), NumInits(numInits), Capacity(numInits), 721 LBraceLoc(lbraceloc), RBraceLoc(rbraceloc), SyntacticForm(0), 722 UnionFieldInit(0), HadArrayRangeDesignator(false) 723{ 724 if (NumInits == 0) 725 return; 726 727 InitExprs = new (C) Stmt*[Capacity]; 728 729 for (unsigned I = 0; I != NumInits; ++I) { 730 Expr *Ex = initExprs[I]; 731 if (Ex->isTypeDependent()) 732 TypeDependent = true; 733 if (Ex->isValueDependent()) 734 ValueDependent = true; 735 InitExprs[I] = Ex; 736 } 737} 738 739void InitListExpr::DoDestroy(ASTContext &C) { 740 DestroyChildren(C); 741 if (InitExprs) 742 C.Deallocate(InitExprs); 743 this->~InitListExpr(); 744 C.Deallocate((void*) this); 745} 746 747void InitListExpr::reserveInits(ASTContext &C, unsigned newCapacity) { 748 if (newCapacity > Capacity) { 749 if (!Capacity) 750 Capacity = newCapacity; 751 else if ((Capacity *= 2) < newCapacity) 752 Capacity = newCapacity; 753 754 Stmt **newInits = new (C) Stmt*[Capacity]; 755 if (InitExprs) { 756 memcpy(newInits, InitExprs, NumInits * sizeof(*InitExprs)); 757 C.Deallocate(InitExprs); 758 } 759 InitExprs = newInits; 760 } 761} 762 763void InitListExpr::resizeInits(ASTContext &C, unsigned N) { 764 // If the new number of expressions is less than the old one, destroy 765 // the expressions that are beyond the new size. 766 for (unsigned i = N, LastIdx = NumInits; i < LastIdx; ++i) 767 InitExprs[i]->Destroy(C); 768 769 // If we are expanding the number of expressions, reserve space. 770 reserveInits(C, N); 771 772 // If we are expanding the number of expressions, zero out beyond our 773 // current capacity. 774 for (unsigned i = NumInits; i < N; ++i) 775 InitExprs[i] = 0; 776 777 NumInits = N; 778} 779 780Expr *InitListExpr::updateInit(ASTContext &C, unsigned Init, Expr *expr) { 781 if (Init >= NumInits) { 782 // Resize the number of initializers. This will adjust the amount 783 // of memory allocated as well as zero-pad the initializers. 784 resizeInits(C, Init+1); 785 } 786 787 Expr *Result = cast_or_null<Expr>(InitExprs[Init]); 788 InitExprs[Init] = expr; 789 return Result; 790} 791 792/// getFunctionType - Return the underlying function type for this block. 793/// 794const FunctionType *BlockExpr::getFunctionType() const { 795 return getType()->getAs<BlockPointerType>()-> 796 getPointeeType()->getAs<FunctionType>(); 797} 798 799SourceLocation BlockExpr::getCaretLocation() const { 800 return TheBlock->getCaretLocation(); 801} 802const Stmt *BlockExpr::getBody() const { 803 return TheBlock->getBody(); 804} 805Stmt *BlockExpr::getBody() { 806 return TheBlock->getBody(); 807} 808 809 810//===----------------------------------------------------------------------===// 811// Generic Expression Routines 812//===----------------------------------------------------------------------===// 813 814/// isUnusedResultAWarning - Return true if this immediate expression should 815/// be warned about if the result is unused. If so, fill in Loc and Ranges 816/// with location to warn on and the source range[s] to report with the 817/// warning. 818bool Expr::isUnusedResultAWarning(SourceLocation &Loc, SourceRange &R1, 819 SourceRange &R2, ASTContext &Ctx) const { 820 // Don't warn if the expr is type dependent. The type could end up 821 // instantiating to void. 822 if (isTypeDependent()) 823 return false; 824 825 switch (getStmtClass()) { 826 default: 827 Loc = getExprLoc(); 828 R1 = getSourceRange(); 829 return true; 830 case ParenExprClass: 831 return cast<ParenExpr>(this)->getSubExpr()-> 832 isUnusedResultAWarning(Loc, R1, R2, Ctx); 833 case UnaryOperatorClass: { 834 const UnaryOperator *UO = cast<UnaryOperator>(this); 835 836 switch (UO->getOpcode()) { 837 default: break; 838 case UnaryOperator::PostInc: 839 case UnaryOperator::PostDec: 840 case UnaryOperator::PreInc: 841 case UnaryOperator::PreDec: // ++/-- 842 return false; // Not a warning. 843 case UnaryOperator::Deref: 844 // Dereferencing a volatile pointer is a side-effect. 845 if (Ctx.getCanonicalType(getType()).isVolatileQualified()) 846 return false; 847 break; 848 case UnaryOperator::Real: 849 case UnaryOperator::Imag: 850 // accessing a piece of a volatile complex is a side-effect. 851 if (Ctx.getCanonicalType(UO->getSubExpr()->getType()) 852 .isVolatileQualified()) 853 return false; 854 break; 855 case UnaryOperator::Extension: 856 return UO->getSubExpr()->isUnusedResultAWarning(Loc, R1, R2, Ctx); 857 } 858 Loc = UO->getOperatorLoc(); 859 R1 = UO->getSubExpr()->getSourceRange(); 860 return true; 861 } 862 case BinaryOperatorClass: { 863 const BinaryOperator *BO = cast<BinaryOperator>(this); 864 // Consider comma to have side effects if the LHS or RHS does. 865 if (BO->getOpcode() == BinaryOperator::Comma) { 866 // ((foo = <blah>), 0) is an idiom for hiding the result (and 867 // lvalue-ness) of an assignment written in a macro. 868 if (IntegerLiteral *IE = 869 dyn_cast<IntegerLiteral>(BO->getRHS()->IgnoreParens())) 870 if (IE->getValue() == 0) 871 return false; 872 873 return (BO->getRHS()->isUnusedResultAWarning(Loc, R1, R2, Ctx) || 874 BO->getLHS()->isUnusedResultAWarning(Loc, R1, R2, Ctx)); 875 } 876 877 if (BO->isAssignmentOp()) 878 return false; 879 Loc = BO->getOperatorLoc(); 880 R1 = BO->getLHS()->getSourceRange(); 881 R2 = BO->getRHS()->getSourceRange(); 882 return true; 883 } 884 case CompoundAssignOperatorClass: 885 return false; 886 887 case ConditionalOperatorClass: { 888 // The condition must be evaluated, but if either the LHS or RHS is a 889 // warning, warn about them. 890 const ConditionalOperator *Exp = cast<ConditionalOperator>(this); 891 if (Exp->getLHS() && 892 Exp->getLHS()->isUnusedResultAWarning(Loc, R1, R2, Ctx)) 893 return true; 894 return Exp->getRHS()->isUnusedResultAWarning(Loc, R1, R2, Ctx); 895 } 896 897 case MemberExprClass: 898 // If the base pointer or element is to a volatile pointer/field, accessing 899 // it is a side effect. 900 if (Ctx.getCanonicalType(getType()).isVolatileQualified()) 901 return false; 902 Loc = cast<MemberExpr>(this)->getMemberLoc(); 903 R1 = SourceRange(Loc, Loc); 904 R2 = cast<MemberExpr>(this)->getBase()->getSourceRange(); 905 return true; 906 907 case ArraySubscriptExprClass: 908 // If the base pointer or element is to a volatile pointer/field, accessing 909 // it is a side effect. 910 if (Ctx.getCanonicalType(getType()).isVolatileQualified()) 911 return false; 912 Loc = cast<ArraySubscriptExpr>(this)->getRBracketLoc(); 913 R1 = cast<ArraySubscriptExpr>(this)->getLHS()->getSourceRange(); 914 R2 = cast<ArraySubscriptExpr>(this)->getRHS()->getSourceRange(); 915 return true; 916 917 case CallExprClass: 918 case CXXOperatorCallExprClass: 919 case CXXMemberCallExprClass: { 920 // If this is a direct call, get the callee. 921 const CallExpr *CE = cast<CallExpr>(this); 922 if (const Decl *FD = CE->getCalleeDecl()) { 923 // If the callee has attribute pure, const, or warn_unused_result, warn 924 // about it. void foo() { strlen("bar"); } should warn. 925 // 926 // Note: If new cases are added here, DiagnoseUnusedExprResult should be 927 // updated to match for QoI. 928 if (FD->getAttr<WarnUnusedResultAttr>() || 929 FD->getAttr<PureAttr>() || FD->getAttr<ConstAttr>()) { 930 Loc = CE->getCallee()->getLocStart(); 931 R1 = CE->getCallee()->getSourceRange(); 932 933 if (unsigned NumArgs = CE->getNumArgs()) 934 R2 = SourceRange(CE->getArg(0)->getLocStart(), 935 CE->getArg(NumArgs-1)->getLocEnd()); 936 return true; 937 } 938 } 939 return false; 940 } 941 942 case CXXTemporaryObjectExprClass: 943 case CXXConstructExprClass: 944 return false; 945 946 case ObjCMessageExprClass: 947 return false; 948 949 case ObjCImplicitSetterGetterRefExprClass: { // Dot syntax for message send. 950#if 0 951 const ObjCImplicitSetterGetterRefExpr *Ref = 952 cast<ObjCImplicitSetterGetterRefExpr>(this); 953 // FIXME: We really want the location of the '.' here. 954 Loc = Ref->getLocation(); 955 R1 = SourceRange(Ref->getLocation(), Ref->getLocation()); 956 if (Ref->getBase()) 957 R2 = Ref->getBase()->getSourceRange(); 958#else 959 Loc = getExprLoc(); 960 R1 = getSourceRange(); 961#endif 962 return true; 963 } 964 case StmtExprClass: { 965 // Statement exprs don't logically have side effects themselves, but are 966 // sometimes used in macros in ways that give them a type that is unused. 967 // For example ({ blah; foo(); }) will end up with a type if foo has a type. 968 // however, if the result of the stmt expr is dead, we don't want to emit a 969 // warning. 970 const CompoundStmt *CS = cast<StmtExpr>(this)->getSubStmt(); 971 if (!CS->body_empty()) 972 if (const Expr *E = dyn_cast<Expr>(CS->body_back())) 973 return E->isUnusedResultAWarning(Loc, R1, R2, Ctx); 974 975 Loc = cast<StmtExpr>(this)->getLParenLoc(); 976 R1 = getSourceRange(); 977 return true; 978 } 979 case CStyleCastExprClass: 980 // If this is an explicit cast to void, allow it. People do this when they 981 // think they know what they're doing :). 982 if (getType()->isVoidType()) 983 return false; 984 Loc = cast<CStyleCastExpr>(this)->getLParenLoc(); 985 R1 = cast<CStyleCastExpr>(this)->getSubExpr()->getSourceRange(); 986 return true; 987 case CXXFunctionalCastExprClass: { 988 const CastExpr *CE = cast<CastExpr>(this); 989 990 // If this is a cast to void or a constructor conversion, check the operand. 991 // Otherwise, the result of the cast is unused. 992 if (CE->getCastKind() == CastExpr::CK_ToVoid || 993 CE->getCastKind() == CastExpr::CK_ConstructorConversion) 994 return (cast<CastExpr>(this)->getSubExpr() 995 ->isUnusedResultAWarning(Loc, R1, R2, Ctx)); 996 Loc = cast<CXXFunctionalCastExpr>(this)->getTypeBeginLoc(); 997 R1 = cast<CXXFunctionalCastExpr>(this)->getSubExpr()->getSourceRange(); 998 return true; 999 } 1000 1001 case ImplicitCastExprClass: 1002 // Check the operand, since implicit casts are inserted by Sema 1003 return (cast<ImplicitCastExpr>(this) 1004 ->getSubExpr()->isUnusedResultAWarning(Loc, R1, R2, Ctx)); 1005 1006 case CXXDefaultArgExprClass: 1007 return (cast<CXXDefaultArgExpr>(this) 1008 ->getExpr()->isUnusedResultAWarning(Loc, R1, R2, Ctx)); 1009 1010 case CXXNewExprClass: 1011 // FIXME: In theory, there might be new expressions that don't have side 1012 // effects (e.g. a placement new with an uninitialized POD). 1013 case CXXDeleteExprClass: 1014 return false; 1015 case CXXBindTemporaryExprClass: 1016 return (cast<CXXBindTemporaryExpr>(this) 1017 ->getSubExpr()->isUnusedResultAWarning(Loc, R1, R2, Ctx)); 1018 case CXXExprWithTemporariesClass: 1019 return (cast<CXXExprWithTemporaries>(this) 1020 ->getSubExpr()->isUnusedResultAWarning(Loc, R1, R2, Ctx)); 1021 } 1022} 1023 1024/// DeclCanBeLvalue - Determine whether the given declaration can be 1025/// an lvalue. This is a helper routine for isLvalue. 1026static bool DeclCanBeLvalue(const NamedDecl *Decl, ASTContext &Ctx) { 1027 // C++ [temp.param]p6: 1028 // A non-type non-reference template-parameter is not an lvalue. 1029 if (const NonTypeTemplateParmDecl *NTTParm 1030 = dyn_cast<NonTypeTemplateParmDecl>(Decl)) 1031 return NTTParm->getType()->isReferenceType(); 1032 1033 return isa<VarDecl>(Decl) || isa<FieldDecl>(Decl) || 1034 // C++ 3.10p2: An lvalue refers to an object or function. 1035 (Ctx.getLangOptions().CPlusPlus && 1036 (isa<FunctionDecl>(Decl) || isa<FunctionTemplateDecl>(Decl))); 1037} 1038 1039/// isLvalue - C99 6.3.2.1: an lvalue is an expression with an object type or an 1040/// incomplete type other than void. Nonarray expressions that can be lvalues: 1041/// - name, where name must be a variable 1042/// - e[i] 1043/// - (e), where e must be an lvalue 1044/// - e.name, where e must be an lvalue 1045/// - e->name 1046/// - *e, the type of e cannot be a function type 1047/// - string-constant 1048/// - (__real__ e) and (__imag__ e) where e is an lvalue [GNU extension] 1049/// - reference type [C++ [expr]] 1050/// 1051Expr::isLvalueResult Expr::isLvalue(ASTContext &Ctx) const { 1052 assert(!TR->isReferenceType() && "Expressions can't have reference type."); 1053 1054 isLvalueResult Res = isLvalueInternal(Ctx); 1055 if (Res != LV_Valid || Ctx.getLangOptions().CPlusPlus) 1056 return Res; 1057 1058 // first, check the type (C99 6.3.2.1). Expressions with function 1059 // type in C are not lvalues, but they can be lvalues in C++. 1060 if (TR->isFunctionType() || TR == Ctx.OverloadTy) 1061 return LV_NotObjectType; 1062 1063 // Allow qualified void which is an incomplete type other than void (yuck). 1064 if (TR->isVoidType() && !Ctx.getCanonicalType(TR).hasQualifiers()) 1065 return LV_IncompleteVoidType; 1066 1067 return LV_Valid; 1068} 1069 1070// Check whether the expression can be sanely treated like an l-value 1071Expr::isLvalueResult Expr::isLvalueInternal(ASTContext &Ctx) const { 1072 switch (getStmtClass()) { 1073 case ObjCIsaExprClass: 1074 case StringLiteralClass: // C99 6.5.1p4 1075 case ObjCEncodeExprClass: // @encode behaves like its string in every way. 1076 return LV_Valid; 1077 case ArraySubscriptExprClass: // C99 6.5.3p4 (e1[e2] == (*((e1)+(e2)))) 1078 // For vectors, make sure base is an lvalue (i.e. not a function call). 1079 if (cast<ArraySubscriptExpr>(this)->getBase()->getType()->isVectorType()) 1080 return cast<ArraySubscriptExpr>(this)->getBase()->isLvalue(Ctx); 1081 return LV_Valid; 1082 case DeclRefExprClass: { // C99 6.5.1p2 1083 const NamedDecl *RefdDecl = cast<DeclRefExpr>(this)->getDecl(); 1084 if (DeclCanBeLvalue(RefdDecl, Ctx)) 1085 return LV_Valid; 1086 break; 1087 } 1088 case BlockDeclRefExprClass: { 1089 const BlockDeclRefExpr *BDR = cast<BlockDeclRefExpr>(this); 1090 if (isa<VarDecl>(BDR->getDecl())) 1091 return LV_Valid; 1092 break; 1093 } 1094 case MemberExprClass: { 1095 const MemberExpr *m = cast<MemberExpr>(this); 1096 if (Ctx.getLangOptions().CPlusPlus) { // C++ [expr.ref]p4: 1097 NamedDecl *Member = m->getMemberDecl(); 1098 // C++ [expr.ref]p4: 1099 // If E2 is declared to have type "reference to T", then E1.E2 1100 // is an lvalue. 1101 if (ValueDecl *Value = dyn_cast<ValueDecl>(Member)) 1102 if (Value->getType()->isReferenceType()) 1103 return LV_Valid; 1104 1105 // -- If E2 is a static data member [...] then E1.E2 is an lvalue. 1106 if (isa<VarDecl>(Member) && Member->getDeclContext()->isRecord()) 1107 return LV_Valid; 1108 1109 // -- If E2 is a non-static data member [...]. If E1 is an 1110 // lvalue, then E1.E2 is an lvalue. 1111 if (isa<FieldDecl>(Member)) { 1112 if (m->isArrow()) 1113 return LV_Valid; 1114 return m->getBase()->isLvalue(Ctx); 1115 } 1116 1117 // -- If it refers to a static member function [...], then 1118 // E1.E2 is an lvalue. 1119 // -- Otherwise, if E1.E2 refers to a non-static member 1120 // function [...], then E1.E2 is not an lvalue. 1121 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Member)) 1122 return Method->isStatic()? LV_Valid : LV_MemberFunction; 1123 1124 // -- If E2 is a member enumerator [...], the expression E1.E2 1125 // is not an lvalue. 1126 if (isa<EnumConstantDecl>(Member)) 1127 return LV_InvalidExpression; 1128 1129 // Not an lvalue. 1130 return LV_InvalidExpression; 1131 } 1132 1133 // C99 6.5.2.3p4 1134 if (m->isArrow()) 1135 return LV_Valid; 1136 Expr *BaseExp = m->getBase(); 1137 if (BaseExp->getStmtClass() == ObjCPropertyRefExprClass) 1138 return LV_SubObjCPropertySetting; 1139 return 1140 (BaseExp->getStmtClass() == ObjCImplicitSetterGetterRefExprClass) ? 1141 LV_SubObjCPropertyGetterSetting : BaseExp->isLvalue(Ctx); 1142 } 1143 case UnaryOperatorClass: 1144 if (cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::Deref) 1145 return LV_Valid; // C99 6.5.3p4 1146 1147 if (cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::Real || 1148 cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::Imag || 1149 cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::Extension) 1150 return cast<UnaryOperator>(this)->getSubExpr()->isLvalue(Ctx); // GNU. 1151 1152 if (Ctx.getLangOptions().CPlusPlus && // C++ [expr.pre.incr]p1 1153 (cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::PreInc || 1154 cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::PreDec)) 1155 return LV_Valid; 1156 break; 1157 case ImplicitCastExprClass: 1158 if (cast<ImplicitCastExpr>(this)->isLvalueCast()) 1159 return LV_Valid; 1160 1161 // If this is a conversion to a class temporary, make a note of 1162 // that. 1163 if (Ctx.getLangOptions().CPlusPlus && getType()->isRecordType()) 1164 return LV_ClassTemporary; 1165 1166 break; 1167 case ParenExprClass: // C99 6.5.1p5 1168 return cast<ParenExpr>(this)->getSubExpr()->isLvalue(Ctx); 1169 case BinaryOperatorClass: 1170 case CompoundAssignOperatorClass: { 1171 const BinaryOperator *BinOp = cast<BinaryOperator>(this); 1172 1173 if (Ctx.getLangOptions().CPlusPlus && // C++ [expr.comma]p1 1174 BinOp->getOpcode() == BinaryOperator::Comma) 1175 return BinOp->getRHS()->isLvalue(Ctx); 1176 1177 // C++ [expr.mptr.oper]p6 1178 // The result of a .* expression is an lvalue only if its first operand is 1179 // an lvalue and its second operand is a pointer to data member. 1180 if (BinOp->getOpcode() == BinaryOperator::PtrMemD && 1181 !BinOp->getType()->isFunctionType()) 1182 return BinOp->getLHS()->isLvalue(Ctx); 1183 1184 // The result of an ->* expression is an lvalue only if its second operand 1185 // is a pointer to data member. 1186 if (BinOp->getOpcode() == BinaryOperator::PtrMemI && 1187 !BinOp->getType()->isFunctionType()) { 1188 QualType Ty = BinOp->getRHS()->getType(); 1189 if (Ty->isMemberPointerType() && !Ty->isMemberFunctionPointerType()) 1190 return LV_Valid; 1191 } 1192 1193 if (!BinOp->isAssignmentOp()) 1194 return LV_InvalidExpression; 1195 1196 if (Ctx.getLangOptions().CPlusPlus) 1197 // C++ [expr.ass]p1: 1198 // The result of an assignment operation [...] is an lvalue. 1199 return LV_Valid; 1200 1201 1202 // C99 6.5.16: 1203 // An assignment expression [...] is not an lvalue. 1204 return LV_InvalidExpression; 1205 } 1206 case CallExprClass: 1207 case CXXOperatorCallExprClass: 1208 case CXXMemberCallExprClass: { 1209 // C++0x [expr.call]p10 1210 // A function call is an lvalue if and only if the result type 1211 // is an lvalue reference. 1212 QualType ReturnType = cast<CallExpr>(this)->getCallReturnType(); 1213 if (ReturnType->isLValueReferenceType()) 1214 return LV_Valid; 1215 1216 // If the function is returning a class temporary, make a note of 1217 // that. 1218 if (Ctx.getLangOptions().CPlusPlus && ReturnType->isRecordType()) 1219 return LV_ClassTemporary; 1220 1221 break; 1222 } 1223 case CompoundLiteralExprClass: // C99 6.5.2.5p5 1224 // FIXME: Is this what we want in C++? 1225 return LV_Valid; 1226 case ChooseExprClass: 1227 // __builtin_choose_expr is an lvalue if the selected operand is. 1228 return cast<ChooseExpr>(this)->getChosenSubExpr(Ctx)->isLvalue(Ctx); 1229 case ExtVectorElementExprClass: 1230 if (cast<ExtVectorElementExpr>(this)->containsDuplicateElements()) 1231 return LV_DuplicateVectorComponents; 1232 return LV_Valid; 1233 case ObjCIvarRefExprClass: // ObjC instance variables are lvalues. 1234 return LV_Valid; 1235 case ObjCPropertyRefExprClass: // FIXME: check if read-only property. 1236 return LV_Valid; 1237 case ObjCImplicitSetterGetterRefExprClass: // FIXME: check if read-only property. 1238 return LV_Valid; 1239 case PredefinedExprClass: 1240 return LV_Valid; 1241 case UnresolvedLookupExprClass: 1242 return LV_Valid; 1243 case CXXDefaultArgExprClass: 1244 return cast<CXXDefaultArgExpr>(this)->getExpr()->isLvalue(Ctx); 1245 case CStyleCastExprClass: 1246 case CXXFunctionalCastExprClass: 1247 case CXXStaticCastExprClass: 1248 case CXXDynamicCastExprClass: 1249 case CXXReinterpretCastExprClass: 1250 case CXXConstCastExprClass: 1251 // The result of an explicit cast is an lvalue if the type we are 1252 // casting to is an lvalue reference type. See C++ [expr.cast]p1, 1253 // C++ [expr.static.cast]p2, C++ [expr.dynamic.cast]p2, 1254 // C++ [expr.reinterpret.cast]p1, C++ [expr.const.cast]p1. 1255 if (cast<ExplicitCastExpr>(this)->getTypeAsWritten()-> 1256 isLValueReferenceType()) 1257 return LV_Valid; 1258 1259 // If this is a conversion to a class temporary, make a note of 1260 // that. 1261 if (Ctx.getLangOptions().CPlusPlus && 1262 cast<ExplicitCastExpr>(this)->getTypeAsWritten()->isRecordType()) 1263 return LV_ClassTemporary; 1264 1265 break; 1266 case CXXTypeidExprClass: 1267 // C++ 5.2.8p1: The result of a typeid expression is an lvalue of ... 1268 return LV_Valid; 1269 case CXXBindTemporaryExprClass: 1270 return cast<CXXBindTemporaryExpr>(this)->getSubExpr()-> 1271 isLvalueInternal(Ctx); 1272 case CXXBindReferenceExprClass: 1273 // Something that's bound to a reference is always an lvalue. 1274 return LV_Valid; 1275 case ConditionalOperatorClass: { 1276 // Complicated handling is only for C++. 1277 if (!Ctx.getLangOptions().CPlusPlus) 1278 return LV_InvalidExpression; 1279 1280 // Sema should have taken care to ensure that a CXXTemporaryObjectExpr is 1281 // everywhere there's an object converted to an rvalue. Also, any other 1282 // casts should be wrapped by ImplicitCastExprs. There's just the special 1283 // case involving throws to work out. 1284 const ConditionalOperator *Cond = cast<ConditionalOperator>(this); 1285 Expr *True = Cond->getTrueExpr(); 1286 Expr *False = Cond->getFalseExpr(); 1287 // C++0x 5.16p2 1288 // If either the second or the third operand has type (cv) void, [...] 1289 // the result [...] is an rvalue. 1290 if (True->getType()->isVoidType() || False->getType()->isVoidType()) 1291 return LV_InvalidExpression; 1292 1293 // Both sides must be lvalues for the result to be an lvalue. 1294 if (True->isLvalue(Ctx) != LV_Valid || False->isLvalue(Ctx) != LV_Valid) 1295 return LV_InvalidExpression; 1296 1297 // That's it. 1298 return LV_Valid; 1299 } 1300 1301 case Expr::CXXExprWithTemporariesClass: 1302 return cast<CXXExprWithTemporaries>(this)->getSubExpr()->isLvalue(Ctx); 1303 1304 case Expr::ObjCMessageExprClass: 1305 if (const ObjCMethodDecl *Method 1306 = cast<ObjCMessageExpr>(this)->getMethodDecl()) 1307 if (Method->getResultType()->isLValueReferenceType()) 1308 return LV_Valid; 1309 break; 1310 1311 case Expr::CXXConstructExprClass: 1312 case Expr::CXXTemporaryObjectExprClass: 1313 case Expr::CXXZeroInitValueExprClass: 1314 return LV_ClassTemporary; 1315 1316 default: 1317 break; 1318 } 1319 return LV_InvalidExpression; 1320} 1321 1322/// isModifiableLvalue - C99 6.3.2.1: an lvalue that does not have array type, 1323/// does not have an incomplete type, does not have a const-qualified type, and 1324/// if it is a structure or union, does not have any member (including, 1325/// recursively, any member or element of all contained aggregates or unions) 1326/// with a const-qualified type. 1327Expr::isModifiableLvalueResult 1328Expr::isModifiableLvalue(ASTContext &Ctx, SourceLocation *Loc) const { 1329 isLvalueResult lvalResult = isLvalue(Ctx); 1330 1331 switch (lvalResult) { 1332 case LV_Valid: 1333 // C++ 3.10p11: Functions cannot be modified, but pointers to 1334 // functions can be modifiable. 1335 if (Ctx.getLangOptions().CPlusPlus && TR->isFunctionType()) 1336 return MLV_NotObjectType; 1337 break; 1338 1339 case LV_NotObjectType: return MLV_NotObjectType; 1340 case LV_IncompleteVoidType: return MLV_IncompleteVoidType; 1341 case LV_DuplicateVectorComponents: return MLV_DuplicateVectorComponents; 1342 case LV_InvalidExpression: 1343 // If the top level is a C-style cast, and the subexpression is a valid 1344 // lvalue, then this is probably a use of the old-school "cast as lvalue" 1345 // GCC extension. We don't support it, but we want to produce good 1346 // diagnostics when it happens so that the user knows why. 1347 if (const CStyleCastExpr *CE = dyn_cast<CStyleCastExpr>(IgnoreParens())) { 1348 if (CE->getSubExpr()->isLvalue(Ctx) == LV_Valid) { 1349 if (Loc) 1350 *Loc = CE->getLParenLoc(); 1351 return MLV_LValueCast; 1352 } 1353 } 1354 return MLV_InvalidExpression; 1355 case LV_MemberFunction: return MLV_MemberFunction; 1356 case LV_SubObjCPropertySetting: return MLV_SubObjCPropertySetting; 1357 case LV_SubObjCPropertyGetterSetting: 1358 return MLV_SubObjCPropertyGetterSetting; 1359 case LV_ClassTemporary: 1360 return MLV_ClassTemporary; 1361 } 1362 1363 // The following is illegal: 1364 // void takeclosure(void (^C)(void)); 1365 // void func() { int x = 1; takeclosure(^{ x = 7; }); } 1366 // 1367 if (const BlockDeclRefExpr *BDR = dyn_cast<BlockDeclRefExpr>(this)) { 1368 if (!BDR->isByRef() && isa<VarDecl>(BDR->getDecl())) 1369 return MLV_NotBlockQualified; 1370 } 1371 1372 // Assigning to an 'implicit' property? 1373 if (const ObjCImplicitSetterGetterRefExpr* Expr = 1374 dyn_cast<ObjCImplicitSetterGetterRefExpr>(this)) { 1375 if (Expr->getSetterMethod() == 0) 1376 return MLV_NoSetterProperty; 1377 } 1378 1379 QualType CT = Ctx.getCanonicalType(getType()); 1380 1381 if (CT.isConstQualified()) 1382 return MLV_ConstQualified; 1383 if (CT->isArrayType()) 1384 return MLV_ArrayType; 1385 if (CT->isIncompleteType()) 1386 return MLV_IncompleteType; 1387 1388 if (const RecordType *r = CT->getAs<RecordType>()) { 1389 if (r->hasConstFields()) 1390 return MLV_ConstQualified; 1391 } 1392 1393 return MLV_Valid; 1394} 1395 1396/// isOBJCGCCandidate - Check if an expression is objc gc'able. 1397/// returns true, if it is; false otherwise. 1398bool Expr::isOBJCGCCandidate(ASTContext &Ctx) const { 1399 switch (getStmtClass()) { 1400 default: 1401 return false; 1402 case ObjCIvarRefExprClass: 1403 return true; 1404 case Expr::UnaryOperatorClass: 1405 return cast<UnaryOperator>(this)->getSubExpr()->isOBJCGCCandidate(Ctx); 1406 case ParenExprClass: 1407 return cast<ParenExpr>(this)->getSubExpr()->isOBJCGCCandidate(Ctx); 1408 case ImplicitCastExprClass: 1409 return cast<ImplicitCastExpr>(this)->getSubExpr()->isOBJCGCCandidate(Ctx); 1410 case CStyleCastExprClass: 1411 return cast<CStyleCastExpr>(this)->getSubExpr()->isOBJCGCCandidate(Ctx); 1412 case DeclRefExprClass: { 1413 const Decl *D = cast<DeclRefExpr>(this)->getDecl(); 1414 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 1415 if (VD->hasGlobalStorage()) 1416 return true; 1417 QualType T = VD->getType(); 1418 // dereferencing to a pointer is always a gc'able candidate, 1419 // unless it is __weak. 1420 return T->isPointerType() && 1421 (Ctx.getObjCGCAttrKind(T) != Qualifiers::Weak); 1422 } 1423 return false; 1424 } 1425 case MemberExprClass: { 1426 const MemberExpr *M = cast<MemberExpr>(this); 1427 return M->getBase()->isOBJCGCCandidate(Ctx); 1428 } 1429 case ArraySubscriptExprClass: 1430 return cast<ArraySubscriptExpr>(this)->getBase()->isOBJCGCCandidate(Ctx); 1431 } 1432} 1433Expr* Expr::IgnoreParens() { 1434 Expr* E = this; 1435 while (ParenExpr* P = dyn_cast<ParenExpr>(E)) 1436 E = P->getSubExpr(); 1437 1438 return E; 1439} 1440 1441/// IgnoreParenCasts - Ignore parentheses and casts. Strip off any ParenExpr 1442/// or CastExprs or ImplicitCastExprs, returning their operand. 1443Expr *Expr::IgnoreParenCasts() { 1444 Expr *E = this; 1445 while (true) { 1446 if (ParenExpr *P = dyn_cast<ParenExpr>(E)) 1447 E = P->getSubExpr(); 1448 else if (CastExpr *P = dyn_cast<CastExpr>(E)) 1449 E = P->getSubExpr(); 1450 else 1451 return E; 1452 } 1453} 1454 1455/// IgnoreParenNoopCasts - Ignore parentheses and casts that do not change the 1456/// value (including ptr->int casts of the same size). Strip off any 1457/// ParenExpr or CastExprs, returning their operand. 1458Expr *Expr::IgnoreParenNoopCasts(ASTContext &Ctx) { 1459 Expr *E = this; 1460 while (true) { 1461 if (ParenExpr *P = dyn_cast<ParenExpr>(E)) { 1462 E = P->getSubExpr(); 1463 continue; 1464 } 1465 1466 if (CastExpr *P = dyn_cast<CastExpr>(E)) { 1467 // We ignore integer <-> casts that are of the same width, ptr<->ptr and 1468 // ptr<->int casts of the same width. We also ignore all identify casts. 1469 Expr *SE = P->getSubExpr(); 1470 1471 if (Ctx.hasSameUnqualifiedType(E->getType(), SE->getType())) { 1472 E = SE; 1473 continue; 1474 } 1475 1476 if ((E->getType()->isPointerType() || E->getType()->isIntegralType()) && 1477 (SE->getType()->isPointerType() || SE->getType()->isIntegralType()) && 1478 Ctx.getTypeSize(E->getType()) == Ctx.getTypeSize(SE->getType())) { 1479 E = SE; 1480 continue; 1481 } 1482 } 1483 1484 return E; 1485 } 1486} 1487 1488bool Expr::isDefaultArgument() const { 1489 const Expr *E = this; 1490 while (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) 1491 E = ICE->getSubExprAsWritten(); 1492 1493 return isa<CXXDefaultArgExpr>(E); 1494} 1495 1496/// hasAnyTypeDependentArguments - Determines if any of the expressions 1497/// in Exprs is type-dependent. 1498bool Expr::hasAnyTypeDependentArguments(Expr** Exprs, unsigned NumExprs) { 1499 for (unsigned I = 0; I < NumExprs; ++I) 1500 if (Exprs[I]->isTypeDependent()) 1501 return true; 1502 1503 return false; 1504} 1505 1506/// hasAnyValueDependentArguments - Determines if any of the expressions 1507/// in Exprs is value-dependent. 1508bool Expr::hasAnyValueDependentArguments(Expr** Exprs, unsigned NumExprs) { 1509 for (unsigned I = 0; I < NumExprs; ++I) 1510 if (Exprs[I]->isValueDependent()) 1511 return true; 1512 1513 return false; 1514} 1515 1516bool Expr::isConstantInitializer(ASTContext &Ctx) const { 1517 // This function is attempting whether an expression is an initializer 1518 // which can be evaluated at compile-time. isEvaluatable handles most 1519 // of the cases, but it can't deal with some initializer-specific 1520 // expressions, and it can't deal with aggregates; we deal with those here, 1521 // and fall back to isEvaluatable for the other cases. 1522 1523 // FIXME: This function assumes the variable being assigned to 1524 // isn't a reference type! 1525 1526 switch (getStmtClass()) { 1527 default: break; 1528 case StringLiteralClass: 1529 case ObjCStringLiteralClass: 1530 case ObjCEncodeExprClass: 1531 return true; 1532 case CompoundLiteralExprClass: { 1533 // This handles gcc's extension that allows global initializers like 1534 // "struct x {int x;} x = (struct x) {};". 1535 // FIXME: This accepts other cases it shouldn't! 1536 const Expr *Exp = cast<CompoundLiteralExpr>(this)->getInitializer(); 1537 return Exp->isConstantInitializer(Ctx); 1538 } 1539 case InitListExprClass: { 1540 // FIXME: This doesn't deal with fields with reference types correctly. 1541 // FIXME: This incorrectly allows pointers cast to integers to be assigned 1542 // to bitfields. 1543 const InitListExpr *Exp = cast<InitListExpr>(this); 1544 unsigned numInits = Exp->getNumInits(); 1545 for (unsigned i = 0; i < numInits; i++) { 1546 if (!Exp->getInit(i)->isConstantInitializer(Ctx)) 1547 return false; 1548 } 1549 return true; 1550 } 1551 case ImplicitValueInitExprClass: 1552 return true; 1553 case ParenExprClass: 1554 return cast<ParenExpr>(this)->getSubExpr()->isConstantInitializer(Ctx); 1555 case UnaryOperatorClass: { 1556 const UnaryOperator* Exp = cast<UnaryOperator>(this); 1557 if (Exp->getOpcode() == UnaryOperator::Extension) 1558 return Exp->getSubExpr()->isConstantInitializer(Ctx); 1559 break; 1560 } 1561 case BinaryOperatorClass: { 1562 // Special case &&foo - &&bar. It would be nice to generalize this somehow 1563 // but this handles the common case. 1564 const BinaryOperator *Exp = cast<BinaryOperator>(this); 1565 if (Exp->getOpcode() == BinaryOperator::Sub && 1566 isa<AddrLabelExpr>(Exp->getLHS()->IgnoreParenNoopCasts(Ctx)) && 1567 isa<AddrLabelExpr>(Exp->getRHS()->IgnoreParenNoopCasts(Ctx))) 1568 return true; 1569 break; 1570 } 1571 case ImplicitCastExprClass: 1572 case CStyleCastExprClass: 1573 // Handle casts with a destination that's a struct or union; this 1574 // deals with both the gcc no-op struct cast extension and the 1575 // cast-to-union extension. 1576 if (getType()->isRecordType()) 1577 return cast<CastExpr>(this)->getSubExpr()->isConstantInitializer(Ctx); 1578 1579 // Integer->integer casts can be handled here, which is important for 1580 // things like (int)(&&x-&&y). Scary but true. 1581 if (getType()->isIntegerType() && 1582 cast<CastExpr>(this)->getSubExpr()->getType()->isIntegerType()) 1583 return cast<CastExpr>(this)->getSubExpr()->isConstantInitializer(Ctx); 1584 1585 break; 1586 } 1587 return isEvaluatable(Ctx); 1588} 1589 1590/// isIntegerConstantExpr - this recursive routine will test if an expression is 1591/// an integer constant expression. 1592 1593/// FIXME: Pass up a reason why! Invalid operation in i-c-e, division by zero, 1594/// comma, etc 1595/// 1596/// FIXME: Handle offsetof. Two things to do: Handle GCC's __builtin_offsetof 1597/// to support gcc 4.0+ and handle the idiom GCC recognizes with a null pointer 1598/// cast+dereference. 1599 1600// CheckICE - This function does the fundamental ICE checking: the returned 1601// ICEDiag contains a Val of 0, 1, or 2, and a possibly null SourceLocation. 1602// Note that to reduce code duplication, this helper does no evaluation 1603// itself; the caller checks whether the expression is evaluatable, and 1604// in the rare cases where CheckICE actually cares about the evaluated 1605// value, it calls into Evalute. 1606// 1607// Meanings of Val: 1608// 0: This expression is an ICE if it can be evaluated by Evaluate. 1609// 1: This expression is not an ICE, but if it isn't evaluated, it's 1610// a legal subexpression for an ICE. This return value is used to handle 1611// the comma operator in C99 mode. 1612// 2: This expression is not an ICE, and is not a legal subexpression for one. 1613 1614struct ICEDiag { 1615 unsigned Val; 1616 SourceLocation Loc; 1617 1618 public: 1619 ICEDiag(unsigned v, SourceLocation l) : Val(v), Loc(l) {} 1620 ICEDiag() : Val(0) {} 1621}; 1622 1623ICEDiag NoDiag() { return ICEDiag(); } 1624 1625static ICEDiag CheckEvalInICE(const Expr* E, ASTContext &Ctx) { 1626 Expr::EvalResult EVResult; 1627 if (!E->Evaluate(EVResult, Ctx) || EVResult.HasSideEffects || 1628 !EVResult.Val.isInt()) { 1629 return ICEDiag(2, E->getLocStart()); 1630 } 1631 return NoDiag(); 1632} 1633 1634static ICEDiag CheckICE(const Expr* E, ASTContext &Ctx) { 1635 assert(!E->isValueDependent() && "Should not see value dependent exprs!"); 1636 if (!E->getType()->isIntegralType()) { 1637 return ICEDiag(2, E->getLocStart()); 1638 } 1639 1640 switch (E->getStmtClass()) { 1641#define STMT(Node, Base) case Expr::Node##Class: 1642#define EXPR(Node, Base) 1643#include "clang/AST/StmtNodes.def" 1644 case Expr::PredefinedExprClass: 1645 case Expr::FloatingLiteralClass: 1646 case Expr::ImaginaryLiteralClass: 1647 case Expr::StringLiteralClass: 1648 case Expr::ArraySubscriptExprClass: 1649 case Expr::MemberExprClass: 1650 case Expr::CompoundAssignOperatorClass: 1651 case Expr::CompoundLiteralExprClass: 1652 case Expr::ExtVectorElementExprClass: 1653 case Expr::InitListExprClass: 1654 case Expr::DesignatedInitExprClass: 1655 case Expr::ImplicitValueInitExprClass: 1656 case Expr::ParenListExprClass: 1657 case Expr::VAArgExprClass: 1658 case Expr::AddrLabelExprClass: 1659 case Expr::StmtExprClass: 1660 case Expr::CXXMemberCallExprClass: 1661 case Expr::CXXDynamicCastExprClass: 1662 case Expr::CXXTypeidExprClass: 1663 case Expr::CXXNullPtrLiteralExprClass: 1664 case Expr::CXXThisExprClass: 1665 case Expr::CXXThrowExprClass: 1666 case Expr::CXXNewExprClass: 1667 case Expr::CXXDeleteExprClass: 1668 case Expr::CXXPseudoDestructorExprClass: 1669 case Expr::UnresolvedLookupExprClass: 1670 case Expr::DependentScopeDeclRefExprClass: 1671 case Expr::CXXConstructExprClass: 1672 case Expr::CXXBindTemporaryExprClass: 1673 case Expr::CXXBindReferenceExprClass: 1674 case Expr::CXXExprWithTemporariesClass: 1675 case Expr::CXXTemporaryObjectExprClass: 1676 case Expr::CXXUnresolvedConstructExprClass: 1677 case Expr::CXXDependentScopeMemberExprClass: 1678 case Expr::UnresolvedMemberExprClass: 1679 case Expr::ObjCStringLiteralClass: 1680 case Expr::ObjCEncodeExprClass: 1681 case Expr::ObjCMessageExprClass: 1682 case Expr::ObjCSelectorExprClass: 1683 case Expr::ObjCProtocolExprClass: 1684 case Expr::ObjCIvarRefExprClass: 1685 case Expr::ObjCPropertyRefExprClass: 1686 case Expr::ObjCImplicitSetterGetterRefExprClass: 1687 case Expr::ObjCSuperExprClass: 1688 case Expr::ObjCIsaExprClass: 1689 case Expr::ShuffleVectorExprClass: 1690 case Expr::BlockExprClass: 1691 case Expr::BlockDeclRefExprClass: 1692 case Expr::NoStmtClass: 1693 return ICEDiag(2, E->getLocStart()); 1694 1695 case Expr::GNUNullExprClass: 1696 // GCC considers the GNU __null value to be an integral constant expression. 1697 return NoDiag(); 1698 1699 case Expr::ParenExprClass: 1700 return CheckICE(cast<ParenExpr>(E)->getSubExpr(), Ctx); 1701 case Expr::IntegerLiteralClass: 1702 case Expr::CharacterLiteralClass: 1703 case Expr::CXXBoolLiteralExprClass: 1704 case Expr::CXXZeroInitValueExprClass: 1705 case Expr::TypesCompatibleExprClass: 1706 case Expr::UnaryTypeTraitExprClass: 1707 return NoDiag(); 1708 case Expr::CallExprClass: 1709 case Expr::CXXOperatorCallExprClass: { 1710 const CallExpr *CE = cast<CallExpr>(E); 1711 if (CE->isBuiltinCall(Ctx)) 1712 return CheckEvalInICE(E, Ctx); 1713 return ICEDiag(2, E->getLocStart()); 1714 } 1715 case Expr::DeclRefExprClass: 1716 if (isa<EnumConstantDecl>(cast<DeclRefExpr>(E)->getDecl())) 1717 return NoDiag(); 1718 if (Ctx.getLangOptions().CPlusPlus && 1719 E->getType().getCVRQualifiers() == Qualifiers::Const) { 1720 // C++ 7.1.5.1p2 1721 // A variable of non-volatile const-qualified integral or enumeration 1722 // type initialized by an ICE can be used in ICEs. 1723 if (const VarDecl *Dcl = 1724 dyn_cast<VarDecl>(cast<DeclRefExpr>(E)->getDecl())) { 1725 Qualifiers Quals = Ctx.getCanonicalType(Dcl->getType()).getQualifiers(); 1726 if (Quals.hasVolatile() || !Quals.hasConst()) 1727 return ICEDiag(2, cast<DeclRefExpr>(E)->getLocation()); 1728 1729 // Look for a declaration of this variable that has an initializer. 1730 const VarDecl *ID = 0; 1731 const Expr *Init = Dcl->getAnyInitializer(ID); 1732 if (Init) { 1733 if (ID->isInitKnownICE()) { 1734 // We have already checked whether this subexpression is an 1735 // integral constant expression. 1736 if (ID->isInitICE()) 1737 return NoDiag(); 1738 else 1739 return ICEDiag(2, cast<DeclRefExpr>(E)->getLocation()); 1740 } 1741 1742 // It's an ICE whether or not the definition we found is 1743 // out-of-line. See DR 721 and the discussion in Clang PR 1744 // 6206 for details. 1745 1746 if (Dcl->isCheckingICE()) { 1747 return ICEDiag(2, cast<DeclRefExpr>(E)->getLocation()); 1748 } 1749 1750 Dcl->setCheckingICE(); 1751 ICEDiag Result = CheckICE(Init, Ctx); 1752 // Cache the result of the ICE test. 1753 Dcl->setInitKnownICE(Result.Val == 0); 1754 return Result; 1755 } 1756 } 1757 } 1758 return ICEDiag(2, E->getLocStart()); 1759 case Expr::UnaryOperatorClass: { 1760 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1761 switch (Exp->getOpcode()) { 1762 case UnaryOperator::PostInc: 1763 case UnaryOperator::PostDec: 1764 case UnaryOperator::PreInc: 1765 case UnaryOperator::PreDec: 1766 case UnaryOperator::AddrOf: 1767 case UnaryOperator::Deref: 1768 return ICEDiag(2, E->getLocStart()); 1769 1770 case UnaryOperator::Extension: 1771 case UnaryOperator::LNot: 1772 case UnaryOperator::Plus: 1773 case UnaryOperator::Minus: 1774 case UnaryOperator::Not: 1775 case UnaryOperator::Real: 1776 case UnaryOperator::Imag: 1777 return CheckICE(Exp->getSubExpr(), Ctx); 1778 case UnaryOperator::OffsetOf: 1779 // Note that per C99, offsetof must be an ICE. And AFAIK, using 1780 // Evaluate matches the proposed gcc behavior for cases like 1781 // "offsetof(struct s{int x[4];}, x[!.0])". This doesn't affect 1782 // compliance: we should warn earlier for offsetof expressions with 1783 // array subscripts that aren't ICEs, and if the array subscripts 1784 // are ICEs, the value of the offsetof must be an integer constant. 1785 return CheckEvalInICE(E, Ctx); 1786 } 1787 } 1788 case Expr::SizeOfAlignOfExprClass: { 1789 const SizeOfAlignOfExpr *Exp = cast<SizeOfAlignOfExpr>(E); 1790 if (Exp->isSizeOf() && Exp->getTypeOfArgument()->isVariableArrayType()) 1791 return ICEDiag(2, E->getLocStart()); 1792 return NoDiag(); 1793 } 1794 case Expr::BinaryOperatorClass: { 1795 const BinaryOperator *Exp = cast<BinaryOperator>(E); 1796 switch (Exp->getOpcode()) { 1797 case BinaryOperator::PtrMemD: 1798 case BinaryOperator::PtrMemI: 1799 case BinaryOperator::Assign: 1800 case BinaryOperator::MulAssign: 1801 case BinaryOperator::DivAssign: 1802 case BinaryOperator::RemAssign: 1803 case BinaryOperator::AddAssign: 1804 case BinaryOperator::SubAssign: 1805 case BinaryOperator::ShlAssign: 1806 case BinaryOperator::ShrAssign: 1807 case BinaryOperator::AndAssign: 1808 case BinaryOperator::XorAssign: 1809 case BinaryOperator::OrAssign: 1810 return ICEDiag(2, E->getLocStart()); 1811 1812 case BinaryOperator::Mul: 1813 case BinaryOperator::Div: 1814 case BinaryOperator::Rem: 1815 case BinaryOperator::Add: 1816 case BinaryOperator::Sub: 1817 case BinaryOperator::Shl: 1818 case BinaryOperator::Shr: 1819 case BinaryOperator::LT: 1820 case BinaryOperator::GT: 1821 case BinaryOperator::LE: 1822 case BinaryOperator::GE: 1823 case BinaryOperator::EQ: 1824 case BinaryOperator::NE: 1825 case BinaryOperator::And: 1826 case BinaryOperator::Xor: 1827 case BinaryOperator::Or: 1828 case BinaryOperator::Comma: { 1829 ICEDiag LHSResult = CheckICE(Exp->getLHS(), Ctx); 1830 ICEDiag RHSResult = CheckICE(Exp->getRHS(), Ctx); 1831 if (Exp->getOpcode() == BinaryOperator::Div || 1832 Exp->getOpcode() == BinaryOperator::Rem) { 1833 // Evaluate gives an error for undefined Div/Rem, so make sure 1834 // we don't evaluate one. 1835 if (LHSResult.Val != 2 && RHSResult.Val != 2) { 1836 llvm::APSInt REval = Exp->getRHS()->EvaluateAsInt(Ctx); 1837 if (REval == 0) 1838 return ICEDiag(1, E->getLocStart()); 1839 if (REval.isSigned() && REval.isAllOnesValue()) { 1840 llvm::APSInt LEval = Exp->getLHS()->EvaluateAsInt(Ctx); 1841 if (LEval.isMinSignedValue()) 1842 return ICEDiag(1, E->getLocStart()); 1843 } 1844 } 1845 } 1846 if (Exp->getOpcode() == BinaryOperator::Comma) { 1847 if (Ctx.getLangOptions().C99) { 1848 // C99 6.6p3 introduces a strange edge case: comma can be in an ICE 1849 // if it isn't evaluated. 1850 if (LHSResult.Val == 0 && RHSResult.Val == 0) 1851 return ICEDiag(1, E->getLocStart()); 1852 } else { 1853 // In both C89 and C++, commas in ICEs are illegal. 1854 return ICEDiag(2, E->getLocStart()); 1855 } 1856 } 1857 if (LHSResult.Val >= RHSResult.Val) 1858 return LHSResult; 1859 return RHSResult; 1860 } 1861 case BinaryOperator::LAnd: 1862 case BinaryOperator::LOr: { 1863 ICEDiag LHSResult = CheckICE(Exp->getLHS(), Ctx); 1864 ICEDiag RHSResult = CheckICE(Exp->getRHS(), Ctx); 1865 if (LHSResult.Val == 0 && RHSResult.Val == 1) { 1866 // Rare case where the RHS has a comma "side-effect"; we need 1867 // to actually check the condition to see whether the side 1868 // with the comma is evaluated. 1869 if ((Exp->getOpcode() == BinaryOperator::LAnd) != 1870 (Exp->getLHS()->EvaluateAsInt(Ctx) == 0)) 1871 return RHSResult; 1872 return NoDiag(); 1873 } 1874 1875 if (LHSResult.Val >= RHSResult.Val) 1876 return LHSResult; 1877 return RHSResult; 1878 } 1879 } 1880 } 1881 case Expr::ImplicitCastExprClass: 1882 case Expr::CStyleCastExprClass: 1883 case Expr::CXXFunctionalCastExprClass: 1884 case Expr::CXXNamedCastExprClass: 1885 case Expr::CXXStaticCastExprClass: 1886 case Expr::CXXReinterpretCastExprClass: 1887 case Expr::CXXConstCastExprClass: { 1888 const Expr *SubExpr = cast<CastExpr>(E)->getSubExpr(); 1889 if (SubExpr->getType()->isIntegralType()) 1890 return CheckICE(SubExpr, Ctx); 1891 if (isa<FloatingLiteral>(SubExpr->IgnoreParens())) 1892 return NoDiag(); 1893 return ICEDiag(2, E->getLocStart()); 1894 } 1895 case Expr::ConditionalOperatorClass: { 1896 const ConditionalOperator *Exp = cast<ConditionalOperator>(E); 1897 // If the condition (ignoring parens) is a __builtin_constant_p call, 1898 // then only the true side is actually considered in an integer constant 1899 // expression, and it is fully evaluated. This is an important GNU 1900 // extension. See GCC PR38377 for discussion. 1901 if (const CallExpr *CallCE = dyn_cast<CallExpr>(Exp->getCond()->IgnoreParenCasts())) 1902 if (CallCE->isBuiltinCall(Ctx) == Builtin::BI__builtin_constant_p) { 1903 Expr::EvalResult EVResult; 1904 if (!E->Evaluate(EVResult, Ctx) || EVResult.HasSideEffects || 1905 !EVResult.Val.isInt()) { 1906 return ICEDiag(2, E->getLocStart()); 1907 } 1908 return NoDiag(); 1909 } 1910 ICEDiag CondResult = CheckICE(Exp->getCond(), Ctx); 1911 ICEDiag TrueResult = CheckICE(Exp->getTrueExpr(), Ctx); 1912 ICEDiag FalseResult = CheckICE(Exp->getFalseExpr(), Ctx); 1913 if (CondResult.Val == 2) 1914 return CondResult; 1915 if (TrueResult.Val == 2) 1916 return TrueResult; 1917 if (FalseResult.Val == 2) 1918 return FalseResult; 1919 if (CondResult.Val == 1) 1920 return CondResult; 1921 if (TrueResult.Val == 0 && FalseResult.Val == 0) 1922 return NoDiag(); 1923 // Rare case where the diagnostics depend on which side is evaluated 1924 // Note that if we get here, CondResult is 0, and at least one of 1925 // TrueResult and FalseResult is non-zero. 1926 if (Exp->getCond()->EvaluateAsInt(Ctx) == 0) { 1927 return FalseResult; 1928 } 1929 return TrueResult; 1930 } 1931 case Expr::CXXDefaultArgExprClass: 1932 return CheckICE(cast<CXXDefaultArgExpr>(E)->getExpr(), Ctx); 1933 case Expr::ChooseExprClass: { 1934 return CheckICE(cast<ChooseExpr>(E)->getChosenSubExpr(Ctx), Ctx); 1935 } 1936 } 1937 1938 // Silence a GCC warning 1939 return ICEDiag(2, E->getLocStart()); 1940} 1941 1942bool Expr::isIntegerConstantExpr(llvm::APSInt &Result, ASTContext &Ctx, 1943 SourceLocation *Loc, bool isEvaluated) const { 1944 ICEDiag d = CheckICE(this, Ctx); 1945 if (d.Val != 0) { 1946 if (Loc) *Loc = d.Loc; 1947 return false; 1948 } 1949 EvalResult EvalResult; 1950 if (!Evaluate(EvalResult, Ctx)) 1951 llvm_unreachable("ICE cannot be evaluated!"); 1952 assert(!EvalResult.HasSideEffects && "ICE with side effects!"); 1953 assert(EvalResult.Val.isInt() && "ICE that isn't integer!"); 1954 Result = EvalResult.Val.getInt(); 1955 return true; 1956} 1957 1958/// isNullPointerConstant - C99 6.3.2.3p3 - Return true if this is either an 1959/// integer constant expression with the value zero, or if this is one that is 1960/// cast to void*. 1961bool Expr::isNullPointerConstant(ASTContext &Ctx, 1962 NullPointerConstantValueDependence NPC) const { 1963 if (isValueDependent()) { 1964 switch (NPC) { 1965 case NPC_NeverValueDependent: 1966 assert(false && "Unexpected value dependent expression!"); 1967 // If the unthinkable happens, fall through to the safest alternative. 1968 1969 case NPC_ValueDependentIsNull: 1970 return isTypeDependent() || getType()->isIntegralType(); 1971 1972 case NPC_ValueDependentIsNotNull: 1973 return false; 1974 } 1975 } 1976 1977 // Strip off a cast to void*, if it exists. Except in C++. 1978 if (const ExplicitCastExpr *CE = dyn_cast<ExplicitCastExpr>(this)) { 1979 if (!Ctx.getLangOptions().CPlusPlus) { 1980 // Check that it is a cast to void*. 1981 if (const PointerType *PT = CE->getType()->getAs<PointerType>()) { 1982 QualType Pointee = PT->getPointeeType(); 1983 if (!Pointee.hasQualifiers() && 1984 Pointee->isVoidType() && // to void* 1985 CE->getSubExpr()->getType()->isIntegerType()) // from int. 1986 return CE->getSubExpr()->isNullPointerConstant(Ctx, NPC); 1987 } 1988 } 1989 } else if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(this)) { 1990 // Ignore the ImplicitCastExpr type entirely. 1991 return ICE->getSubExpr()->isNullPointerConstant(Ctx, NPC); 1992 } else if (const ParenExpr *PE = dyn_cast<ParenExpr>(this)) { 1993 // Accept ((void*)0) as a null pointer constant, as many other 1994 // implementations do. 1995 return PE->getSubExpr()->isNullPointerConstant(Ctx, NPC); 1996 } else if (const CXXDefaultArgExpr *DefaultArg 1997 = dyn_cast<CXXDefaultArgExpr>(this)) { 1998 // See through default argument expressions 1999 return DefaultArg->getExpr()->isNullPointerConstant(Ctx, NPC); 2000 } else if (isa<GNUNullExpr>(this)) { 2001 // The GNU __null extension is always a null pointer constant. 2002 return true; 2003 } 2004 2005 // C++0x nullptr_t is always a null pointer constant. 2006 if (getType()->isNullPtrType()) 2007 return true; 2008 2009 // This expression must be an integer type. 2010 if (!getType()->isIntegerType() || 2011 (Ctx.getLangOptions().CPlusPlus && getType()->isEnumeralType())) 2012 return false; 2013 2014 // If we have an integer constant expression, we need to *evaluate* it and 2015 // test for the value 0. 2016 llvm::APSInt Result; 2017 return isIntegerConstantExpr(Result, Ctx) && Result == 0; 2018} 2019 2020FieldDecl *Expr::getBitField() { 2021 Expr *E = this->IgnoreParens(); 2022 2023 while (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) { 2024 if (ICE->isLvalueCast() && ICE->getCastKind() == CastExpr::CK_NoOp) 2025 E = ICE->getSubExpr()->IgnoreParens(); 2026 else 2027 break; 2028 } 2029 2030 if (MemberExpr *MemRef = dyn_cast<MemberExpr>(E)) 2031 if (FieldDecl *Field = dyn_cast<FieldDecl>(MemRef->getMemberDecl())) 2032 if (Field->isBitField()) 2033 return Field; 2034 2035 if (BinaryOperator *BinOp = dyn_cast<BinaryOperator>(E)) 2036 if (BinOp->isAssignmentOp() && BinOp->getLHS()) 2037 return BinOp->getLHS()->getBitField(); 2038 2039 return 0; 2040} 2041 2042bool Expr::refersToVectorElement() const { 2043 const Expr *E = this->IgnoreParens(); 2044 2045 while (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) { 2046 if (ICE->isLvalueCast() && ICE->getCastKind() == CastExpr::CK_NoOp) 2047 E = ICE->getSubExpr()->IgnoreParens(); 2048 else 2049 break; 2050 } 2051 2052 if (const ArraySubscriptExpr *ASE = dyn_cast<ArraySubscriptExpr>(E)) 2053 return ASE->getBase()->getType()->isVectorType(); 2054 2055 if (isa<ExtVectorElementExpr>(E)) 2056 return true; 2057 2058 return false; 2059} 2060 2061/// isArrow - Return true if the base expression is a pointer to vector, 2062/// return false if the base expression is a vector. 2063bool ExtVectorElementExpr::isArrow() const { 2064 return getBase()->getType()->isPointerType(); 2065} 2066 2067unsigned ExtVectorElementExpr::getNumElements() const { 2068 if (const VectorType *VT = getType()->getAs<VectorType>()) 2069 return VT->getNumElements(); 2070 return 1; 2071} 2072 2073/// containsDuplicateElements - Return true if any element access is repeated. 2074bool ExtVectorElementExpr::containsDuplicateElements() const { 2075 // FIXME: Refactor this code to an accessor on the AST node which returns the 2076 // "type" of component access, and share with code below and in Sema. 2077 llvm::StringRef Comp = Accessor->getName(); 2078 2079 // Halving swizzles do not contain duplicate elements. 2080 if (Comp == "hi" || Comp == "lo" || Comp == "even" || Comp == "odd") 2081 return false; 2082 2083 // Advance past s-char prefix on hex swizzles. 2084 if (Comp[0] == 's' || Comp[0] == 'S') 2085 Comp = Comp.substr(1); 2086 2087 for (unsigned i = 0, e = Comp.size(); i != e; ++i) 2088 if (Comp.substr(i + 1).find(Comp[i]) != llvm::StringRef::npos) 2089 return true; 2090 2091 return false; 2092} 2093 2094/// getEncodedElementAccess - We encode the fields as a llvm ConstantArray. 2095void ExtVectorElementExpr::getEncodedElementAccess( 2096 llvm::SmallVectorImpl<unsigned> &Elts) const { 2097 llvm::StringRef Comp = Accessor->getName(); 2098 if (Comp[0] == 's' || Comp[0] == 'S') 2099 Comp = Comp.substr(1); 2100 2101 bool isHi = Comp == "hi"; 2102 bool isLo = Comp == "lo"; 2103 bool isEven = Comp == "even"; 2104 bool isOdd = Comp == "odd"; 2105 2106 for (unsigned i = 0, e = getNumElements(); i != e; ++i) { 2107 uint64_t Index; 2108 2109 if (isHi) 2110 Index = e + i; 2111 else if (isLo) 2112 Index = i; 2113 else if (isEven) 2114 Index = 2 * i; 2115 else if (isOdd) 2116 Index = 2 * i + 1; 2117 else 2118 Index = ExtVectorType::getAccessorIdx(Comp[i]); 2119 2120 Elts.push_back(Index); 2121 } 2122} 2123 2124// constructor for instance messages. 2125ObjCMessageExpr::ObjCMessageExpr(ASTContext &C, Expr *receiver, 2126 Selector selInfo, 2127 QualType retType, ObjCMethodDecl *mproto, 2128 SourceLocation LBrac, SourceLocation RBrac, 2129 Expr **ArgExprs, unsigned nargs) 2130 : Expr(ObjCMessageExprClass, retType, false, false), SelName(selInfo), 2131 MethodProto(mproto) { 2132 NumArgs = nargs; 2133 SubExprs = new (C) Stmt*[NumArgs+1]; 2134 SubExprs[RECEIVER] = receiver; 2135 if (NumArgs) { 2136 for (unsigned i = 0; i != NumArgs; ++i) 2137 SubExprs[i+ARGS_START] = static_cast<Expr *>(ArgExprs[i]); 2138 } 2139 LBracloc = LBrac; 2140 RBracloc = RBrac; 2141} 2142 2143// constructor for class messages. 2144// FIXME: clsName should be typed to ObjCInterfaceType 2145ObjCMessageExpr::ObjCMessageExpr(ASTContext &C, IdentifierInfo *clsName, 2146 Selector selInfo, QualType retType, 2147 ObjCMethodDecl *mproto, 2148 SourceLocation LBrac, SourceLocation RBrac, 2149 Expr **ArgExprs, unsigned nargs) 2150 : Expr(ObjCMessageExprClass, retType, false, false), SelName(selInfo), 2151 MethodProto(mproto) { 2152 NumArgs = nargs; 2153 SubExprs = new (C) Stmt*[NumArgs+1]; 2154 SubExprs[RECEIVER] = (Expr*) ((uintptr_t) clsName | IsClsMethDeclUnknown); 2155 if (NumArgs) { 2156 for (unsigned i = 0; i != NumArgs; ++i) 2157 SubExprs[i+ARGS_START] = static_cast<Expr *>(ArgExprs[i]); 2158 } 2159 LBracloc = LBrac; 2160 RBracloc = RBrac; 2161} 2162 2163// constructor for class messages. 2164ObjCMessageExpr::ObjCMessageExpr(ASTContext &C, ObjCInterfaceDecl *cls, 2165 Selector selInfo, QualType retType, 2166 ObjCMethodDecl *mproto, SourceLocation LBrac, 2167 SourceLocation RBrac, Expr **ArgExprs, 2168 unsigned nargs) 2169: Expr(ObjCMessageExprClass, retType, false, false), SelName(selInfo), 2170MethodProto(mproto) { 2171 NumArgs = nargs; 2172 SubExprs = new (C) Stmt*[NumArgs+1]; 2173 SubExprs[RECEIVER] = (Expr*) ((uintptr_t) cls | IsClsMethDeclKnown); 2174 if (NumArgs) { 2175 for (unsigned i = 0; i != NumArgs; ++i) 2176 SubExprs[i+ARGS_START] = static_cast<Expr *>(ArgExprs[i]); 2177 } 2178 LBracloc = LBrac; 2179 RBracloc = RBrac; 2180} 2181 2182ObjCMessageExpr::ClassInfo ObjCMessageExpr::getClassInfo() const { 2183 uintptr_t x = (uintptr_t) SubExprs[RECEIVER]; 2184 switch (x & Flags) { 2185 default: 2186 assert(false && "Invalid ObjCMessageExpr."); 2187 case IsInstMeth: 2188 return ClassInfo(0, 0); 2189 case IsClsMethDeclUnknown: 2190 return ClassInfo(0, (IdentifierInfo*) (x & ~Flags)); 2191 case IsClsMethDeclKnown: { 2192 ObjCInterfaceDecl* D = (ObjCInterfaceDecl*) (x & ~Flags); 2193 return ClassInfo(D, D->getIdentifier()); 2194 } 2195 } 2196} 2197 2198void ObjCMessageExpr::setClassInfo(const ObjCMessageExpr::ClassInfo &CI) { 2199 if (CI.first == 0 && CI.second == 0) 2200 SubExprs[RECEIVER] = (Expr*)((uintptr_t)0 | IsInstMeth); 2201 else if (CI.first == 0) 2202 SubExprs[RECEIVER] = (Expr*)((uintptr_t)CI.second | IsClsMethDeclUnknown); 2203 else 2204 SubExprs[RECEIVER] = (Expr*)((uintptr_t)CI.first | IsClsMethDeclKnown); 2205} 2206 2207void ObjCMessageExpr::DoDestroy(ASTContext &C) { 2208 DestroyChildren(C); 2209 if (SubExprs) 2210 C.Deallocate(SubExprs); 2211 this->~ObjCMessageExpr(); 2212 C.Deallocate((void*) this); 2213} 2214 2215bool ChooseExpr::isConditionTrue(ASTContext &C) const { 2216 return getCond()->EvaluateAsInt(C) != 0; 2217} 2218 2219void ShuffleVectorExpr::setExprs(ASTContext &C, Expr ** Exprs, 2220 unsigned NumExprs) { 2221 if (SubExprs) C.Deallocate(SubExprs); 2222 2223 SubExprs = new (C) Stmt* [NumExprs]; 2224 this->NumExprs = NumExprs; 2225 memcpy(SubExprs, Exprs, sizeof(Expr *) * NumExprs); 2226} 2227 2228void ShuffleVectorExpr::DoDestroy(ASTContext& C) { 2229 DestroyChildren(C); 2230 if (SubExprs) C.Deallocate(SubExprs); 2231 this->~ShuffleVectorExpr(); 2232 C.Deallocate(this); 2233} 2234 2235void SizeOfAlignOfExpr::DoDestroy(ASTContext& C) { 2236 // Override default behavior of traversing children. If this has a type 2237 // operand and the type is a variable-length array, the child iteration 2238 // will iterate over the size expression. However, this expression belongs 2239 // to the type, not to this, so we don't want to delete it. 2240 // We still want to delete this expression. 2241 if (isArgumentType()) { 2242 this->~SizeOfAlignOfExpr(); 2243 C.Deallocate(this); 2244 } 2245 else 2246 Expr::DoDestroy(C); 2247} 2248 2249//===----------------------------------------------------------------------===// 2250// DesignatedInitExpr 2251//===----------------------------------------------------------------------===// 2252 2253IdentifierInfo *DesignatedInitExpr::Designator::getFieldName() { 2254 assert(Kind == FieldDesignator && "Only valid on a field designator"); 2255 if (Field.NameOrField & 0x01) 2256 return reinterpret_cast<IdentifierInfo *>(Field.NameOrField&~0x01); 2257 else 2258 return getField()->getIdentifier(); 2259} 2260 2261DesignatedInitExpr::DesignatedInitExpr(ASTContext &C, QualType Ty, 2262 unsigned NumDesignators, 2263 const Designator *Designators, 2264 SourceLocation EqualOrColonLoc, 2265 bool GNUSyntax, 2266 Expr **IndexExprs, 2267 unsigned NumIndexExprs, 2268 Expr *Init) 2269 : Expr(DesignatedInitExprClass, Ty, 2270 Init->isTypeDependent(), Init->isValueDependent()), 2271 EqualOrColonLoc(EqualOrColonLoc), GNUSyntax(GNUSyntax), 2272 NumDesignators(NumDesignators), NumSubExprs(NumIndexExprs + 1) { 2273 this->Designators = new (C) Designator[NumDesignators]; 2274 2275 // Record the initializer itself. 2276 child_iterator Child = child_begin(); 2277 *Child++ = Init; 2278 2279 // Copy the designators and their subexpressions, computing 2280 // value-dependence along the way. 2281 unsigned IndexIdx = 0; 2282 for (unsigned I = 0; I != NumDesignators; ++I) { 2283 this->Designators[I] = Designators[I]; 2284 2285 if (this->Designators[I].isArrayDesignator()) { 2286 // Compute type- and value-dependence. 2287 Expr *Index = IndexExprs[IndexIdx]; 2288 ValueDependent = ValueDependent || 2289 Index->isTypeDependent() || Index->isValueDependent(); 2290 2291 // Copy the index expressions into permanent storage. 2292 *Child++ = IndexExprs[IndexIdx++]; 2293 } else if (this->Designators[I].isArrayRangeDesignator()) { 2294 // Compute type- and value-dependence. 2295 Expr *Start = IndexExprs[IndexIdx]; 2296 Expr *End = IndexExprs[IndexIdx + 1]; 2297 ValueDependent = ValueDependent || 2298 Start->isTypeDependent() || Start->isValueDependent() || 2299 End->isTypeDependent() || End->isValueDependent(); 2300 2301 // Copy the start/end expressions into permanent storage. 2302 *Child++ = IndexExprs[IndexIdx++]; 2303 *Child++ = IndexExprs[IndexIdx++]; 2304 } 2305 } 2306 2307 assert(IndexIdx == NumIndexExprs && "Wrong number of index expressions"); 2308} 2309 2310DesignatedInitExpr * 2311DesignatedInitExpr::Create(ASTContext &C, Designator *Designators, 2312 unsigned NumDesignators, 2313 Expr **IndexExprs, unsigned NumIndexExprs, 2314 SourceLocation ColonOrEqualLoc, 2315 bool UsesColonSyntax, Expr *Init) { 2316 void *Mem = C.Allocate(sizeof(DesignatedInitExpr) + 2317 sizeof(Stmt *) * (NumIndexExprs + 1), 8); 2318 return new (Mem) DesignatedInitExpr(C, C.VoidTy, NumDesignators, Designators, 2319 ColonOrEqualLoc, UsesColonSyntax, 2320 IndexExprs, NumIndexExprs, Init); 2321} 2322 2323DesignatedInitExpr *DesignatedInitExpr::CreateEmpty(ASTContext &C, 2324 unsigned NumIndexExprs) { 2325 void *Mem = C.Allocate(sizeof(DesignatedInitExpr) + 2326 sizeof(Stmt *) * (NumIndexExprs + 1), 8); 2327 return new (Mem) DesignatedInitExpr(NumIndexExprs + 1); 2328} 2329 2330void DesignatedInitExpr::setDesignators(ASTContext &C, 2331 const Designator *Desigs, 2332 unsigned NumDesigs) { 2333 DestroyDesignators(C); 2334 2335 Designators = new (C) Designator[NumDesigs]; 2336 NumDesignators = NumDesigs; 2337 for (unsigned I = 0; I != NumDesigs; ++I) 2338 Designators[I] = Desigs[I]; 2339} 2340 2341SourceRange DesignatedInitExpr::getSourceRange() const { 2342 SourceLocation StartLoc; 2343 Designator &First = 2344 *const_cast<DesignatedInitExpr*>(this)->designators_begin(); 2345 if (First.isFieldDesignator()) { 2346 if (GNUSyntax) 2347 StartLoc = SourceLocation::getFromRawEncoding(First.Field.FieldLoc); 2348 else 2349 StartLoc = SourceLocation::getFromRawEncoding(First.Field.DotLoc); 2350 } else 2351 StartLoc = 2352 SourceLocation::getFromRawEncoding(First.ArrayOrRange.LBracketLoc); 2353 return SourceRange(StartLoc, getInit()->getSourceRange().getEnd()); 2354} 2355 2356Expr *DesignatedInitExpr::getArrayIndex(const Designator& D) { 2357 assert(D.Kind == Designator::ArrayDesignator && "Requires array designator"); 2358 char* Ptr = static_cast<char*>(static_cast<void *>(this)); 2359 Ptr += sizeof(DesignatedInitExpr); 2360 Stmt **SubExprs = reinterpret_cast<Stmt**>(reinterpret_cast<void**>(Ptr)); 2361 return cast<Expr>(*(SubExprs + D.ArrayOrRange.Index + 1)); 2362} 2363 2364Expr *DesignatedInitExpr::getArrayRangeStart(const Designator& D) { 2365 assert(D.Kind == Designator::ArrayRangeDesignator && 2366 "Requires array range designator"); 2367 char* Ptr = static_cast<char*>(static_cast<void *>(this)); 2368 Ptr += sizeof(DesignatedInitExpr); 2369 Stmt **SubExprs = reinterpret_cast<Stmt**>(reinterpret_cast<void**>(Ptr)); 2370 return cast<Expr>(*(SubExprs + D.ArrayOrRange.Index + 1)); 2371} 2372 2373Expr *DesignatedInitExpr::getArrayRangeEnd(const Designator& D) { 2374 assert(D.Kind == Designator::ArrayRangeDesignator && 2375 "Requires array range designator"); 2376 char* Ptr = static_cast<char*>(static_cast<void *>(this)); 2377 Ptr += sizeof(DesignatedInitExpr); 2378 Stmt **SubExprs = reinterpret_cast<Stmt**>(reinterpret_cast<void**>(Ptr)); 2379 return cast<Expr>(*(SubExprs + D.ArrayOrRange.Index + 2)); 2380} 2381 2382/// \brief Replaces the designator at index @p Idx with the series 2383/// of designators in [First, Last). 2384void DesignatedInitExpr::ExpandDesignator(ASTContext &C, unsigned Idx, 2385 const Designator *First, 2386 const Designator *Last) { 2387 unsigned NumNewDesignators = Last - First; 2388 if (NumNewDesignators == 0) { 2389 std::copy_backward(Designators + Idx + 1, 2390 Designators + NumDesignators, 2391 Designators + Idx); 2392 --NumNewDesignators; 2393 return; 2394 } else if (NumNewDesignators == 1) { 2395 Designators[Idx] = *First; 2396 return; 2397 } 2398 2399 Designator *NewDesignators 2400 = new (C) Designator[NumDesignators - 1 + NumNewDesignators]; 2401 std::copy(Designators, Designators + Idx, NewDesignators); 2402 std::copy(First, Last, NewDesignators + Idx); 2403 std::copy(Designators + Idx + 1, Designators + NumDesignators, 2404 NewDesignators + Idx + NumNewDesignators); 2405 DestroyDesignators(C); 2406 Designators = NewDesignators; 2407 NumDesignators = NumDesignators - 1 + NumNewDesignators; 2408} 2409 2410void DesignatedInitExpr::DoDestroy(ASTContext &C) { 2411 DestroyDesignators(C); 2412 Expr::DoDestroy(C); 2413} 2414 2415void DesignatedInitExpr::DestroyDesignators(ASTContext &C) { 2416 for (unsigned I = 0; I != NumDesignators; ++I) 2417 Designators[I].~Designator(); 2418 C.Deallocate(Designators); 2419 Designators = 0; 2420} 2421 2422ParenListExpr::ParenListExpr(ASTContext& C, SourceLocation lparenloc, 2423 Expr **exprs, unsigned nexprs, 2424 SourceLocation rparenloc) 2425: Expr(ParenListExprClass, QualType(), 2426 hasAnyTypeDependentArguments(exprs, nexprs), 2427 hasAnyValueDependentArguments(exprs, nexprs)), 2428 NumExprs(nexprs), LParenLoc(lparenloc), RParenLoc(rparenloc) { 2429 2430 Exprs = new (C) Stmt*[nexprs]; 2431 for (unsigned i = 0; i != nexprs; ++i) 2432 Exprs[i] = exprs[i]; 2433} 2434 2435void ParenListExpr::DoDestroy(ASTContext& C) { 2436 DestroyChildren(C); 2437 if (Exprs) C.Deallocate(Exprs); 2438 this->~ParenListExpr(); 2439 C.Deallocate(this); 2440} 2441 2442//===----------------------------------------------------------------------===// 2443// ExprIterator. 2444//===----------------------------------------------------------------------===// 2445 2446Expr* ExprIterator::operator[](size_t idx) { return cast<Expr>(I[idx]); } 2447Expr* ExprIterator::operator*() const { return cast<Expr>(*I); } 2448Expr* ExprIterator::operator->() const { return cast<Expr>(*I); } 2449const Expr* ConstExprIterator::operator[](size_t idx) const { 2450 return cast<Expr>(I[idx]); 2451} 2452const Expr* ConstExprIterator::operator*() const { return cast<Expr>(*I); } 2453const Expr* ConstExprIterator::operator->() const { return cast<Expr>(*I); } 2454 2455//===----------------------------------------------------------------------===// 2456// Child Iterators for iterating over subexpressions/substatements 2457//===----------------------------------------------------------------------===// 2458 2459// DeclRefExpr 2460Stmt::child_iterator DeclRefExpr::child_begin() { return child_iterator(); } 2461Stmt::child_iterator DeclRefExpr::child_end() { return child_iterator(); } 2462 2463// ObjCIvarRefExpr 2464Stmt::child_iterator ObjCIvarRefExpr::child_begin() { return &Base; } 2465Stmt::child_iterator ObjCIvarRefExpr::child_end() { return &Base+1; } 2466 2467// ObjCPropertyRefExpr 2468Stmt::child_iterator ObjCPropertyRefExpr::child_begin() { return &Base; } 2469Stmt::child_iterator ObjCPropertyRefExpr::child_end() { return &Base+1; } 2470 2471// ObjCImplicitSetterGetterRefExpr 2472Stmt::child_iterator ObjCImplicitSetterGetterRefExpr::child_begin() { 2473 return &Base; 2474} 2475Stmt::child_iterator ObjCImplicitSetterGetterRefExpr::child_end() { 2476 return &Base+1; 2477} 2478 2479// ObjCSuperExpr 2480Stmt::child_iterator ObjCSuperExpr::child_begin() { return child_iterator(); } 2481Stmt::child_iterator ObjCSuperExpr::child_end() { return child_iterator(); } 2482 2483// ObjCIsaExpr 2484Stmt::child_iterator ObjCIsaExpr::child_begin() { return &Base; } 2485Stmt::child_iterator ObjCIsaExpr::child_end() { return &Base+1; } 2486 2487// PredefinedExpr 2488Stmt::child_iterator PredefinedExpr::child_begin() { return child_iterator(); } 2489Stmt::child_iterator PredefinedExpr::child_end() { return child_iterator(); } 2490 2491// IntegerLiteral 2492Stmt::child_iterator IntegerLiteral::child_begin() { return child_iterator(); } 2493Stmt::child_iterator IntegerLiteral::child_end() { return child_iterator(); } 2494 2495// CharacterLiteral 2496Stmt::child_iterator CharacterLiteral::child_begin() { return child_iterator();} 2497Stmt::child_iterator CharacterLiteral::child_end() { return child_iterator(); } 2498 2499// FloatingLiteral 2500Stmt::child_iterator FloatingLiteral::child_begin() { return child_iterator(); } 2501Stmt::child_iterator FloatingLiteral::child_end() { return child_iterator(); } 2502 2503// ImaginaryLiteral 2504Stmt::child_iterator ImaginaryLiteral::child_begin() { return &Val; } 2505Stmt::child_iterator ImaginaryLiteral::child_end() { return &Val+1; } 2506 2507// StringLiteral 2508Stmt::child_iterator StringLiteral::child_begin() { return child_iterator(); } 2509Stmt::child_iterator StringLiteral::child_end() { return child_iterator(); } 2510 2511// ParenExpr 2512Stmt::child_iterator ParenExpr::child_begin() { return &Val; } 2513Stmt::child_iterator ParenExpr::child_end() { return &Val+1; } 2514 2515// UnaryOperator 2516Stmt::child_iterator UnaryOperator::child_begin() { return &Val; } 2517Stmt::child_iterator UnaryOperator::child_end() { return &Val+1; } 2518 2519// SizeOfAlignOfExpr 2520Stmt::child_iterator SizeOfAlignOfExpr::child_begin() { 2521 // If this is of a type and the type is a VLA type (and not a typedef), the 2522 // size expression of the VLA needs to be treated as an executable expression. 2523 // Why isn't this weirdness documented better in StmtIterator? 2524 if (isArgumentType()) { 2525 if (VariableArrayType* T = dyn_cast<VariableArrayType>( 2526 getArgumentType().getTypePtr())) 2527 return child_iterator(T); 2528 return child_iterator(); 2529 } 2530 return child_iterator(&Argument.Ex); 2531} 2532Stmt::child_iterator SizeOfAlignOfExpr::child_end() { 2533 if (isArgumentType()) 2534 return child_iterator(); 2535 return child_iterator(&Argument.Ex + 1); 2536} 2537 2538// ArraySubscriptExpr 2539Stmt::child_iterator ArraySubscriptExpr::child_begin() { 2540 return &SubExprs[0]; 2541} 2542Stmt::child_iterator ArraySubscriptExpr::child_end() { 2543 return &SubExprs[0]+END_EXPR; 2544} 2545 2546// CallExpr 2547Stmt::child_iterator CallExpr::child_begin() { 2548 return &SubExprs[0]; 2549} 2550Stmt::child_iterator CallExpr::child_end() { 2551 return &SubExprs[0]+NumArgs+ARGS_START; 2552} 2553 2554// MemberExpr 2555Stmt::child_iterator MemberExpr::child_begin() { return &Base; } 2556Stmt::child_iterator MemberExpr::child_end() { return &Base+1; } 2557 2558// ExtVectorElementExpr 2559Stmt::child_iterator ExtVectorElementExpr::child_begin() { return &Base; } 2560Stmt::child_iterator ExtVectorElementExpr::child_end() { return &Base+1; } 2561 2562// CompoundLiteralExpr 2563Stmt::child_iterator CompoundLiteralExpr::child_begin() { return &Init; } 2564Stmt::child_iterator CompoundLiteralExpr::child_end() { return &Init+1; } 2565 2566// CastExpr 2567Stmt::child_iterator CastExpr::child_begin() { return &Op; } 2568Stmt::child_iterator CastExpr::child_end() { return &Op+1; } 2569 2570// BinaryOperator 2571Stmt::child_iterator BinaryOperator::child_begin() { 2572 return &SubExprs[0]; 2573} 2574Stmt::child_iterator BinaryOperator::child_end() { 2575 return &SubExprs[0]+END_EXPR; 2576} 2577 2578// ConditionalOperator 2579Stmt::child_iterator ConditionalOperator::child_begin() { 2580 return &SubExprs[0]; 2581} 2582Stmt::child_iterator ConditionalOperator::child_end() { 2583 return &SubExprs[0]+END_EXPR; 2584} 2585 2586// AddrLabelExpr 2587Stmt::child_iterator AddrLabelExpr::child_begin() { return child_iterator(); } 2588Stmt::child_iterator AddrLabelExpr::child_end() { return child_iterator(); } 2589 2590// StmtExpr 2591Stmt::child_iterator StmtExpr::child_begin() { return &SubStmt; } 2592Stmt::child_iterator StmtExpr::child_end() { return &SubStmt+1; } 2593 2594// TypesCompatibleExpr 2595Stmt::child_iterator TypesCompatibleExpr::child_begin() { 2596 return child_iterator(); 2597} 2598 2599Stmt::child_iterator TypesCompatibleExpr::child_end() { 2600 return child_iterator(); 2601} 2602 2603// ChooseExpr 2604Stmt::child_iterator ChooseExpr::child_begin() { return &SubExprs[0]; } 2605Stmt::child_iterator ChooseExpr::child_end() { return &SubExprs[0]+END_EXPR; } 2606 2607// GNUNullExpr 2608Stmt::child_iterator GNUNullExpr::child_begin() { return child_iterator(); } 2609Stmt::child_iterator GNUNullExpr::child_end() { return child_iterator(); } 2610 2611// ShuffleVectorExpr 2612Stmt::child_iterator ShuffleVectorExpr::child_begin() { 2613 return &SubExprs[0]; 2614} 2615Stmt::child_iterator ShuffleVectorExpr::child_end() { 2616 return &SubExprs[0]+NumExprs; 2617} 2618 2619// VAArgExpr 2620Stmt::child_iterator VAArgExpr::child_begin() { return &Val; } 2621Stmt::child_iterator VAArgExpr::child_end() { return &Val+1; } 2622 2623// InitListExpr 2624Stmt::child_iterator InitListExpr::child_begin() { return begin(); } 2625Stmt::child_iterator InitListExpr::child_end() { return end(); } 2626 2627// DesignatedInitExpr 2628Stmt::child_iterator DesignatedInitExpr::child_begin() { 2629 char* Ptr = static_cast<char*>(static_cast<void *>(this)); 2630 Ptr += sizeof(DesignatedInitExpr); 2631 return reinterpret_cast<Stmt**>(reinterpret_cast<void**>(Ptr)); 2632} 2633Stmt::child_iterator DesignatedInitExpr::child_end() { 2634 return child_iterator(&*child_begin() + NumSubExprs); 2635} 2636 2637// ImplicitValueInitExpr 2638Stmt::child_iterator ImplicitValueInitExpr::child_begin() { 2639 return child_iterator(); 2640} 2641 2642Stmt::child_iterator ImplicitValueInitExpr::child_end() { 2643 return child_iterator(); 2644} 2645 2646// ParenListExpr 2647Stmt::child_iterator ParenListExpr::child_begin() { 2648 return &Exprs[0]; 2649} 2650Stmt::child_iterator ParenListExpr::child_end() { 2651 return &Exprs[0]+NumExprs; 2652} 2653 2654// ObjCStringLiteral 2655Stmt::child_iterator ObjCStringLiteral::child_begin() { 2656 return &String; 2657} 2658Stmt::child_iterator ObjCStringLiteral::child_end() { 2659 return &String+1; 2660} 2661 2662// ObjCEncodeExpr 2663Stmt::child_iterator ObjCEncodeExpr::child_begin() { return child_iterator(); } 2664Stmt::child_iterator ObjCEncodeExpr::child_end() { return child_iterator(); } 2665 2666// ObjCSelectorExpr 2667Stmt::child_iterator ObjCSelectorExpr::child_begin() { 2668 return child_iterator(); 2669} 2670Stmt::child_iterator ObjCSelectorExpr::child_end() { 2671 return child_iterator(); 2672} 2673 2674// ObjCProtocolExpr 2675Stmt::child_iterator ObjCProtocolExpr::child_begin() { 2676 return child_iterator(); 2677} 2678Stmt::child_iterator ObjCProtocolExpr::child_end() { 2679 return child_iterator(); 2680} 2681 2682// ObjCMessageExpr 2683Stmt::child_iterator ObjCMessageExpr::child_begin() { 2684 return getReceiver() ? &SubExprs[0] : &SubExprs[0] + ARGS_START; 2685} 2686Stmt::child_iterator ObjCMessageExpr::child_end() { 2687 return &SubExprs[0]+ARGS_START+getNumArgs(); 2688} 2689 2690// Blocks 2691Stmt::child_iterator BlockExpr::child_begin() { return child_iterator(); } 2692Stmt::child_iterator BlockExpr::child_end() { return child_iterator(); } 2693 2694Stmt::child_iterator BlockDeclRefExpr::child_begin() { return child_iterator();} 2695Stmt::child_iterator BlockDeclRefExpr::child_end() { return child_iterator(); } 2696