Expr.cpp revision 5e94a0d82b1f49be41c35a73106b219e3f588c8c
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/APValue.h" 16#include "clang/AST/ASTContext.h" 17#include "clang/AST/DeclObjC.h" 18#include "clang/AST/DeclCXX.h" 19#include "clang/AST/DeclTemplate.h" 20#include "clang/AST/RecordLayout.h" 21#include "clang/AST/StmtVisitor.h" 22#include "clang/Basic/Builtins.h" 23#include "clang/Basic/TargetInfo.h" 24#include <algorithm> 25using namespace clang; 26 27//===----------------------------------------------------------------------===// 28// Primary Expressions. 29//===----------------------------------------------------------------------===// 30 31/// getValueAsApproximateDouble - This returns the value as an inaccurate 32/// double. Note that this may cause loss of precision, but is useful for 33/// debugging dumps, etc. 34double FloatingLiteral::getValueAsApproximateDouble() const { 35 llvm::APFloat V = getValue(); 36 bool ignored; 37 V.convert(llvm::APFloat::IEEEdouble, llvm::APFloat::rmNearestTiesToEven, 38 &ignored); 39 return V.convertToDouble(); 40} 41 42StringLiteral *StringLiteral::Create(ASTContext &C, const char *StrData, 43 unsigned ByteLength, bool Wide, 44 QualType Ty, 45 const SourceLocation *Loc, 46 unsigned NumStrs) { 47 // Allocate enough space for the StringLiteral plus an array of locations for 48 // any concatenated string tokens. 49 void *Mem = C.Allocate(sizeof(StringLiteral)+ 50 sizeof(SourceLocation)*(NumStrs-1), 51 llvm::alignof<StringLiteral>()); 52 StringLiteral *SL = new (Mem) StringLiteral(Ty); 53 54 // OPTIMIZE: could allocate this appended to the StringLiteral. 55 char *AStrData = new (C, 1) char[ByteLength]; 56 memcpy(AStrData, StrData, ByteLength); 57 SL->StrData = AStrData; 58 SL->ByteLength = ByteLength; 59 SL->IsWide = Wide; 60 SL->TokLocs[0] = Loc[0]; 61 SL->NumConcatenated = NumStrs; 62 63 if (NumStrs != 1) 64 memcpy(&SL->TokLocs[1], Loc+1, sizeof(SourceLocation)*(NumStrs-1)); 65 return SL; 66} 67 68StringLiteral *StringLiteral::CreateEmpty(ASTContext &C, unsigned NumStrs) { 69 void *Mem = C.Allocate(sizeof(StringLiteral)+ 70 sizeof(SourceLocation)*(NumStrs-1), 71 llvm::alignof<StringLiteral>()); 72 StringLiteral *SL = new (Mem) StringLiteral(QualType()); 73 SL->StrData = 0; 74 SL->ByteLength = 0; 75 SL->NumConcatenated = NumStrs; 76 return SL; 77} 78 79void StringLiteral::DoDestroy(ASTContext &C) { 80 C.Deallocate(const_cast<char*>(StrData)); 81 Expr::DoDestroy(C); 82} 83 84void StringLiteral::setStrData(ASTContext &C, const char *Str, unsigned Len) { 85 if (StrData) 86 C.Deallocate(const_cast<char*>(StrData)); 87 88 char *AStrData = new (C, 1) char[Len]; 89 memcpy(AStrData, Str, Len); 90 StrData = AStrData; 91 ByteLength = Len; 92} 93 94/// getOpcodeStr - Turn an Opcode enum value into the punctuation char it 95/// corresponds to, e.g. "sizeof" or "[pre]++". 96const char *UnaryOperator::getOpcodeStr(Opcode Op) { 97 switch (Op) { 98 default: assert(0 && "Unknown unary operator"); 99 case PostInc: return "++"; 100 case PostDec: return "--"; 101 case PreInc: return "++"; 102 case PreDec: return "--"; 103 case AddrOf: return "&"; 104 case Deref: return "*"; 105 case Plus: return "+"; 106 case Minus: return "-"; 107 case Not: return "~"; 108 case LNot: return "!"; 109 case Real: return "__real"; 110 case Imag: return "__imag"; 111 case Extension: return "__extension__"; 112 case OffsetOf: return "__builtin_offsetof"; 113 } 114} 115 116UnaryOperator::Opcode 117UnaryOperator::getOverloadedOpcode(OverloadedOperatorKind OO, bool Postfix) { 118 switch (OO) { 119 default: assert(false && "No unary operator for overloaded function"); 120 case OO_PlusPlus: return Postfix ? PostInc : PreInc; 121 case OO_MinusMinus: return Postfix ? PostDec : PreDec; 122 case OO_Amp: return AddrOf; 123 case OO_Star: return Deref; 124 case OO_Plus: return Plus; 125 case OO_Minus: return Minus; 126 case OO_Tilde: return Not; 127 case OO_Exclaim: return LNot; 128 } 129} 130 131OverloadedOperatorKind UnaryOperator::getOverloadedOperator(Opcode Opc) { 132 switch (Opc) { 133 case PostInc: case PreInc: return OO_PlusPlus; 134 case PostDec: case PreDec: return OO_MinusMinus; 135 case AddrOf: return OO_Amp; 136 case Deref: return OO_Star; 137 case Plus: return OO_Plus; 138 case Minus: return OO_Minus; 139 case Not: return OO_Tilde; 140 case LNot: return OO_Exclaim; 141 default: return OO_None; 142 } 143} 144 145 146//===----------------------------------------------------------------------===// 147// Postfix Operators. 148//===----------------------------------------------------------------------===// 149 150CallExpr::CallExpr(ASTContext& C, StmtClass SC, Expr *fn, Expr **args, 151 unsigned numargs, QualType t, SourceLocation rparenloc) 152 : Expr(SC, t, 153 fn->isTypeDependent() || hasAnyTypeDependentArguments(args, numargs), 154 fn->isValueDependent() || hasAnyValueDependentArguments(args,numargs)), 155 NumArgs(numargs) { 156 157 SubExprs = new (C) Stmt*[numargs+1]; 158 SubExprs[FN] = fn; 159 for (unsigned i = 0; i != numargs; ++i) 160 SubExprs[i+ARGS_START] = args[i]; 161 162 RParenLoc = rparenloc; 163} 164 165CallExpr::CallExpr(ASTContext& C, Expr *fn, Expr **args, unsigned numargs, 166 QualType t, SourceLocation rparenloc) 167 : Expr(CallExprClass, t, 168 fn->isTypeDependent() || hasAnyTypeDependentArguments(args, numargs), 169 fn->isValueDependent() || hasAnyValueDependentArguments(args,numargs)), 170 NumArgs(numargs) { 171 172 SubExprs = new (C) Stmt*[numargs+1]; 173 SubExprs[FN] = fn; 174 for (unsigned i = 0; i != numargs; ++i) 175 SubExprs[i+ARGS_START] = args[i]; 176 177 RParenLoc = rparenloc; 178} 179 180CallExpr::CallExpr(ASTContext &C, StmtClass SC, EmptyShell Empty) 181 : Expr(SC, Empty), SubExprs(0), NumArgs(0) { 182 SubExprs = new (C) Stmt*[1]; 183} 184 185void CallExpr::DoDestroy(ASTContext& C) { 186 DestroyChildren(C); 187 if (SubExprs) C.Deallocate(SubExprs); 188 this->~CallExpr(); 189 C.Deallocate(this); 190} 191 192FunctionDecl *CallExpr::getDirectCallee() { 193 Expr *CEE = getCallee()->IgnoreParenCasts(); 194 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) 195 return dyn_cast<FunctionDecl>(DRE->getDecl()); 196 197 return 0; 198} 199 200/// setNumArgs - This changes the number of arguments present in this call. 201/// Any orphaned expressions are deleted by this, and any new operands are set 202/// to null. 203void CallExpr::setNumArgs(ASTContext& C, unsigned NumArgs) { 204 // No change, just return. 205 if (NumArgs == getNumArgs()) return; 206 207 // If shrinking # arguments, just delete the extras and forgot them. 208 if (NumArgs < getNumArgs()) { 209 for (unsigned i = NumArgs, e = getNumArgs(); i != e; ++i) 210 getArg(i)->Destroy(C); 211 this->NumArgs = NumArgs; 212 return; 213 } 214 215 // Otherwise, we are growing the # arguments. New an bigger argument array. 216 Stmt **NewSubExprs = new (C) Stmt*[NumArgs+1]; 217 // Copy over args. 218 for (unsigned i = 0; i != getNumArgs()+ARGS_START; ++i) 219 NewSubExprs[i] = SubExprs[i]; 220 // Null out new args. 221 for (unsigned i = getNumArgs()+ARGS_START; i != NumArgs+ARGS_START; ++i) 222 NewSubExprs[i] = 0; 223 224 if (SubExprs) C.Deallocate(SubExprs); 225 SubExprs = NewSubExprs; 226 this->NumArgs = NumArgs; 227} 228 229/// isBuiltinCall - If this is a call to a builtin, return the builtin ID. If 230/// not, return 0. 231unsigned CallExpr::isBuiltinCall(ASTContext &Context) const { 232 // All simple function calls (e.g. func()) are implicitly cast to pointer to 233 // function. As a result, we try and obtain the DeclRefExpr from the 234 // ImplicitCastExpr. 235 const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(getCallee()); 236 if (!ICE) // FIXME: deal with more complex calls (e.g. (func)(), (*func)()). 237 return 0; 238 239 const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(ICE->getSubExpr()); 240 if (!DRE) 241 return 0; 242 243 const FunctionDecl *FDecl = dyn_cast<FunctionDecl>(DRE->getDecl()); 244 if (!FDecl) 245 return 0; 246 247 if (!FDecl->getIdentifier()) 248 return 0; 249 250 return FDecl->getBuiltinID(Context); 251} 252 253QualType CallExpr::getCallReturnType() const { 254 QualType CalleeType = getCallee()->getType(); 255 if (const PointerType *FnTypePtr = CalleeType->getAs<PointerType>()) 256 CalleeType = FnTypePtr->getPointeeType(); 257 else if (const BlockPointerType *BPT = CalleeType->getAs<BlockPointerType>()) 258 CalleeType = BPT->getPointeeType(); 259 260 const FunctionType *FnType = CalleeType->getAsFunctionType(); 261 return FnType->getResultType(); 262} 263 264/// getOpcodeStr - Turn an Opcode enum value into the punctuation char it 265/// corresponds to, e.g. "<<=". 266const char *BinaryOperator::getOpcodeStr(Opcode Op) { 267 switch (Op) { 268 case PtrMemD: return ".*"; 269 case PtrMemI: return "->*"; 270 case Mul: return "*"; 271 case Div: return "/"; 272 case Rem: return "%"; 273 case Add: return "+"; 274 case Sub: return "-"; 275 case Shl: return "<<"; 276 case Shr: return ">>"; 277 case LT: return "<"; 278 case GT: return ">"; 279 case LE: return "<="; 280 case GE: return ">="; 281 case EQ: return "=="; 282 case NE: return "!="; 283 case And: return "&"; 284 case Xor: return "^"; 285 case Or: return "|"; 286 case LAnd: return "&&"; 287 case LOr: return "||"; 288 case Assign: return "="; 289 case MulAssign: return "*="; 290 case DivAssign: return "/="; 291 case RemAssign: return "%="; 292 case AddAssign: return "+="; 293 case SubAssign: return "-="; 294 case ShlAssign: return "<<="; 295 case ShrAssign: return ">>="; 296 case AndAssign: return "&="; 297 case XorAssign: return "^="; 298 case OrAssign: return "|="; 299 case Comma: return ","; 300 } 301 302 return ""; 303} 304 305BinaryOperator::Opcode 306BinaryOperator::getOverloadedOpcode(OverloadedOperatorKind OO) { 307 switch (OO) { 308 default: assert(false && "Not an overloadable binary operator"); 309 case OO_Plus: return Add; 310 case OO_Minus: return Sub; 311 case OO_Star: return Mul; 312 case OO_Slash: return Div; 313 case OO_Percent: return Rem; 314 case OO_Caret: return Xor; 315 case OO_Amp: return And; 316 case OO_Pipe: return Or; 317 case OO_Equal: return Assign; 318 case OO_Less: return LT; 319 case OO_Greater: return GT; 320 case OO_PlusEqual: return AddAssign; 321 case OO_MinusEqual: return SubAssign; 322 case OO_StarEqual: return MulAssign; 323 case OO_SlashEqual: return DivAssign; 324 case OO_PercentEqual: return RemAssign; 325 case OO_CaretEqual: return XorAssign; 326 case OO_AmpEqual: return AndAssign; 327 case OO_PipeEqual: return OrAssign; 328 case OO_LessLess: return Shl; 329 case OO_GreaterGreater: return Shr; 330 case OO_LessLessEqual: return ShlAssign; 331 case OO_GreaterGreaterEqual: return ShrAssign; 332 case OO_EqualEqual: return EQ; 333 case OO_ExclaimEqual: return NE; 334 case OO_LessEqual: return LE; 335 case OO_GreaterEqual: return GE; 336 case OO_AmpAmp: return LAnd; 337 case OO_PipePipe: return LOr; 338 case OO_Comma: return Comma; 339 case OO_ArrowStar: return PtrMemI; 340 } 341} 342 343OverloadedOperatorKind BinaryOperator::getOverloadedOperator(Opcode Opc) { 344 static const OverloadedOperatorKind OverOps[] = { 345 /* .* Cannot be overloaded */OO_None, OO_ArrowStar, 346 OO_Star, OO_Slash, OO_Percent, 347 OO_Plus, OO_Minus, 348 OO_LessLess, OO_GreaterGreater, 349 OO_Less, OO_Greater, OO_LessEqual, OO_GreaterEqual, 350 OO_EqualEqual, OO_ExclaimEqual, 351 OO_Amp, 352 OO_Caret, 353 OO_Pipe, 354 OO_AmpAmp, 355 OO_PipePipe, 356 OO_Equal, OO_StarEqual, 357 OO_SlashEqual, OO_PercentEqual, 358 OO_PlusEqual, OO_MinusEqual, 359 OO_LessLessEqual, OO_GreaterGreaterEqual, 360 OO_AmpEqual, OO_CaretEqual, 361 OO_PipeEqual, 362 OO_Comma 363 }; 364 return OverOps[Opc]; 365} 366 367InitListExpr::InitListExpr(SourceLocation lbraceloc, 368 Expr **initExprs, unsigned numInits, 369 SourceLocation rbraceloc) 370 : Expr(InitListExprClass, QualType(), 371 hasAnyTypeDependentArguments(initExprs, numInits), 372 hasAnyValueDependentArguments(initExprs, numInits)), 373 LBraceLoc(lbraceloc), RBraceLoc(rbraceloc), SyntacticForm(0), 374 UnionFieldInit(0), HadArrayRangeDesignator(false) { 375 376 InitExprs.insert(InitExprs.end(), initExprs, initExprs+numInits); 377} 378 379void InitListExpr::reserveInits(unsigned NumInits) { 380 if (NumInits > InitExprs.size()) 381 InitExprs.reserve(NumInits); 382} 383 384void InitListExpr::resizeInits(ASTContext &Context, unsigned NumInits) { 385 for (unsigned Idx = NumInits, LastIdx = InitExprs.size(); 386 Idx < LastIdx; ++Idx) 387 InitExprs[Idx]->Destroy(Context); 388 InitExprs.resize(NumInits, 0); 389} 390 391Expr *InitListExpr::updateInit(unsigned Init, Expr *expr) { 392 if (Init >= InitExprs.size()) { 393 InitExprs.insert(InitExprs.end(), Init - InitExprs.size() + 1, 0); 394 InitExprs.back() = expr; 395 return 0; 396 } 397 398 Expr *Result = cast_or_null<Expr>(InitExprs[Init]); 399 InitExprs[Init] = expr; 400 return Result; 401} 402 403/// getFunctionType - Return the underlying function type for this block. 404/// 405const FunctionType *BlockExpr::getFunctionType() const { 406 return getType()->getAs<BlockPointerType>()-> 407 getPointeeType()->getAsFunctionType(); 408} 409 410SourceLocation BlockExpr::getCaretLocation() const { 411 return TheBlock->getCaretLocation(); 412} 413const Stmt *BlockExpr::getBody() const { 414 return TheBlock->getBody(); 415} 416Stmt *BlockExpr::getBody() { 417 return TheBlock->getBody(); 418} 419 420 421//===----------------------------------------------------------------------===// 422// Generic Expression Routines 423//===----------------------------------------------------------------------===// 424 425/// isUnusedResultAWarning - Return true if this immediate expression should 426/// be warned about if the result is unused. If so, fill in Loc and Ranges 427/// with location to warn on and the source range[s] to report with the 428/// warning. 429bool Expr::isUnusedResultAWarning(SourceLocation &Loc, SourceRange &R1, 430 SourceRange &R2) const { 431 // Don't warn if the expr is type dependent. The type could end up 432 // instantiating to void. 433 if (isTypeDependent()) 434 return false; 435 436 switch (getStmtClass()) { 437 default: 438 Loc = getExprLoc(); 439 R1 = getSourceRange(); 440 return true; 441 case ParenExprClass: 442 return cast<ParenExpr>(this)->getSubExpr()-> 443 isUnusedResultAWarning(Loc, R1, R2); 444 case UnaryOperatorClass: { 445 const UnaryOperator *UO = cast<UnaryOperator>(this); 446 447 switch (UO->getOpcode()) { 448 default: break; 449 case UnaryOperator::PostInc: 450 case UnaryOperator::PostDec: 451 case UnaryOperator::PreInc: 452 case UnaryOperator::PreDec: // ++/-- 453 return false; // Not a warning. 454 case UnaryOperator::Deref: 455 // Dereferencing a volatile pointer is a side-effect. 456 if (getType().isVolatileQualified()) 457 return false; 458 break; 459 case UnaryOperator::Real: 460 case UnaryOperator::Imag: 461 // accessing a piece of a volatile complex is a side-effect. 462 if (UO->getSubExpr()->getType().isVolatileQualified()) 463 return false; 464 break; 465 case UnaryOperator::Extension: 466 return UO->getSubExpr()->isUnusedResultAWarning(Loc, R1, R2); 467 } 468 Loc = UO->getOperatorLoc(); 469 R1 = UO->getSubExpr()->getSourceRange(); 470 return true; 471 } 472 case BinaryOperatorClass: { 473 const BinaryOperator *BO = cast<BinaryOperator>(this); 474 // Consider comma to have side effects if the LHS or RHS does. 475 if (BO->getOpcode() == BinaryOperator::Comma) 476 return BO->getRHS()->isUnusedResultAWarning(Loc, R1, R2) || 477 BO->getLHS()->isUnusedResultAWarning(Loc, R1, R2); 478 479 if (BO->isAssignmentOp()) 480 return false; 481 Loc = BO->getOperatorLoc(); 482 R1 = BO->getLHS()->getSourceRange(); 483 R2 = BO->getRHS()->getSourceRange(); 484 return true; 485 } 486 case CompoundAssignOperatorClass: 487 return false; 488 489 case ConditionalOperatorClass: { 490 // The condition must be evaluated, but if either the LHS or RHS is a 491 // warning, warn about them. 492 const ConditionalOperator *Exp = cast<ConditionalOperator>(this); 493 if (Exp->getLHS() && 494 Exp->getLHS()->isUnusedResultAWarning(Loc, R1, R2)) 495 return true; 496 return Exp->getRHS()->isUnusedResultAWarning(Loc, R1, R2); 497 } 498 499 case MemberExprClass: 500 // If the base pointer or element is to a volatile pointer/field, accessing 501 // it is a side effect. 502 if (getType().isVolatileQualified()) 503 return false; 504 Loc = cast<MemberExpr>(this)->getMemberLoc(); 505 R1 = SourceRange(Loc, Loc); 506 R2 = cast<MemberExpr>(this)->getBase()->getSourceRange(); 507 return true; 508 509 case ArraySubscriptExprClass: 510 // If the base pointer or element is to a volatile pointer/field, accessing 511 // it is a side effect. 512 if (getType().isVolatileQualified()) 513 return false; 514 Loc = cast<ArraySubscriptExpr>(this)->getRBracketLoc(); 515 R1 = cast<ArraySubscriptExpr>(this)->getLHS()->getSourceRange(); 516 R2 = cast<ArraySubscriptExpr>(this)->getRHS()->getSourceRange(); 517 return true; 518 519 case CallExprClass: 520 case CXXOperatorCallExprClass: 521 case CXXMemberCallExprClass: { 522 // If this is a direct call, get the callee. 523 const CallExpr *CE = cast<CallExpr>(this); 524 const Expr *CalleeExpr = CE->getCallee()->IgnoreParenCasts(); 525 if (const DeclRefExpr *CalleeDRE = dyn_cast<DeclRefExpr>(CalleeExpr)) { 526 // If the callee has attribute pure, const, or warn_unused_result, warn 527 // about it. void foo() { strlen("bar"); } should warn. 528 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(CalleeDRE->getDecl())) 529 if (FD->getAttr<WarnUnusedResultAttr>() || 530 FD->getAttr<PureAttr>() || FD->getAttr<ConstAttr>()) { 531 Loc = CE->getCallee()->getLocStart(); 532 R1 = CE->getCallee()->getSourceRange(); 533 534 if (unsigned NumArgs = CE->getNumArgs()) 535 R2 = SourceRange(CE->getArg(0)->getLocStart(), 536 CE->getArg(NumArgs-1)->getLocEnd()); 537 return true; 538 } 539 } 540 return false; 541 } 542 case ObjCMessageExprClass: 543 return false; 544 545 case ObjCKVCRefExprClass: { // Dot syntax for message send. 546#if 0 547 const ObjCKVCRefExpr *KVCRef = cast<ObjCKVCRefExpr>(this); 548 // FIXME: We really want the location of the '.' here. 549 Loc = KVCRef->getLocation(); 550 R1 = SourceRange(KVCRef->getLocation(), KVCRef->getLocation()); 551 if (KVCRef->getBase()) 552 R2 = KVCRef->getBase()->getSourceRange(); 553#else 554 Loc = getExprLoc(); 555 R1 = getSourceRange(); 556#endif 557 return true; 558 } 559 case StmtExprClass: { 560 // Statement exprs don't logically have side effects themselves, but are 561 // sometimes used in macros in ways that give them a type that is unused. 562 // For example ({ blah; foo(); }) will end up with a type if foo has a type. 563 // however, if the result of the stmt expr is dead, we don't want to emit a 564 // warning. 565 const CompoundStmt *CS = cast<StmtExpr>(this)->getSubStmt(); 566 if (!CS->body_empty()) 567 if (const Expr *E = dyn_cast<Expr>(CS->body_back())) 568 return E->isUnusedResultAWarning(Loc, R1, R2); 569 570 Loc = cast<StmtExpr>(this)->getLParenLoc(); 571 R1 = getSourceRange(); 572 return true; 573 } 574 case CStyleCastExprClass: 575 // If this is an explicit cast to void, allow it. People do this when they 576 // think they know what they're doing :). 577 if (getType()->isVoidType()) 578 return false; 579 Loc = cast<CStyleCastExpr>(this)->getLParenLoc(); 580 R1 = cast<CStyleCastExpr>(this)->getSubExpr()->getSourceRange(); 581 return true; 582 case CXXFunctionalCastExprClass: 583 // If this is a cast to void, check the operand. Otherwise, the result of 584 // the cast is unused. 585 if (getType()->isVoidType()) 586 return cast<CastExpr>(this)->getSubExpr() 587 ->isUnusedResultAWarning(Loc, R1, R2); 588 Loc = cast<CXXFunctionalCastExpr>(this)->getTypeBeginLoc(); 589 R1 = cast<CXXFunctionalCastExpr>(this)->getSubExpr()->getSourceRange(); 590 return true; 591 592 case ImplicitCastExprClass: 593 // Check the operand, since implicit casts are inserted by Sema 594 return cast<ImplicitCastExpr>(this) 595 ->getSubExpr()->isUnusedResultAWarning(Loc, R1, R2); 596 597 case CXXDefaultArgExprClass: 598 return cast<CXXDefaultArgExpr>(this) 599 ->getExpr()->isUnusedResultAWarning(Loc, R1, R2); 600 601 case CXXNewExprClass: 602 // FIXME: In theory, there might be new expressions that don't have side 603 // effects (e.g. a placement new with an uninitialized POD). 604 case CXXDeleteExprClass: 605 return false; 606 case CXXBindTemporaryExprClass: 607 return cast<CXXBindTemporaryExpr>(this) 608 ->getSubExpr()->isUnusedResultAWarning(Loc, R1, R2); 609 case CXXExprWithTemporariesClass: 610 return cast<CXXExprWithTemporaries>(this) 611 ->getSubExpr()->isUnusedResultAWarning(Loc, R1, R2); 612 } 613} 614 615/// DeclCanBeLvalue - Determine whether the given declaration can be 616/// an lvalue. This is a helper routine for isLvalue. 617static bool DeclCanBeLvalue(const NamedDecl *Decl, ASTContext &Ctx) { 618 // C++ [temp.param]p6: 619 // A non-type non-reference template-parameter is not an lvalue. 620 if (const NonTypeTemplateParmDecl *NTTParm 621 = dyn_cast<NonTypeTemplateParmDecl>(Decl)) 622 return NTTParm->getType()->isReferenceType(); 623 624 return isa<VarDecl>(Decl) || isa<FieldDecl>(Decl) || 625 // C++ 3.10p2: An lvalue refers to an object or function. 626 (Ctx.getLangOptions().CPlusPlus && 627 (isa<FunctionDecl>(Decl) || isa<OverloadedFunctionDecl>(Decl) || 628 isa<FunctionTemplateDecl>(Decl))); 629} 630 631/// isLvalue - C99 6.3.2.1: an lvalue is an expression with an object type or an 632/// incomplete type other than void. Nonarray expressions that can be lvalues: 633/// - name, where name must be a variable 634/// - e[i] 635/// - (e), where e must be an lvalue 636/// - e.name, where e must be an lvalue 637/// - e->name 638/// - *e, the type of e cannot be a function type 639/// - string-constant 640/// - (__real__ e) and (__imag__ e) where e is an lvalue [GNU extension] 641/// - reference type [C++ [expr]] 642/// 643Expr::isLvalueResult Expr::isLvalue(ASTContext &Ctx) const { 644 assert(!TR->isReferenceType() && "Expressions can't have reference type."); 645 646 isLvalueResult Res = isLvalueInternal(Ctx); 647 if (Res != LV_Valid || Ctx.getLangOptions().CPlusPlus) 648 return Res; 649 650 // first, check the type (C99 6.3.2.1). Expressions with function 651 // type in C are not lvalues, but they can be lvalues in C++. 652 if (TR->isFunctionType() || TR == Ctx.OverloadTy) 653 return LV_NotObjectType; 654 655 // Allow qualified void which is an incomplete type other than void (yuck). 656 if (TR->isVoidType() && !Ctx.getCanonicalType(TR).getCVRQualifiers()) 657 return LV_IncompleteVoidType; 658 659 return LV_Valid; 660} 661 662// Check whether the expression can be sanely treated like an l-value 663Expr::isLvalueResult Expr::isLvalueInternal(ASTContext &Ctx) const { 664 switch (getStmtClass()) { 665 case StringLiteralClass: // C99 6.5.1p4 666 case ObjCEncodeExprClass: // @encode behaves like its string in every way. 667 return LV_Valid; 668 case ArraySubscriptExprClass: // C99 6.5.3p4 (e1[e2] == (*((e1)+(e2)))) 669 // For vectors, make sure base is an lvalue (i.e. not a function call). 670 if (cast<ArraySubscriptExpr>(this)->getBase()->getType()->isVectorType()) 671 return cast<ArraySubscriptExpr>(this)->getBase()->isLvalue(Ctx); 672 return LV_Valid; 673 case DeclRefExprClass: 674 case QualifiedDeclRefExprClass: { // C99 6.5.1p2 675 const NamedDecl *RefdDecl = cast<DeclRefExpr>(this)->getDecl(); 676 if (DeclCanBeLvalue(RefdDecl, Ctx)) 677 return LV_Valid; 678 break; 679 } 680 case BlockDeclRefExprClass: { 681 const BlockDeclRefExpr *BDR = cast<BlockDeclRefExpr>(this); 682 if (isa<VarDecl>(BDR->getDecl())) 683 return LV_Valid; 684 break; 685 } 686 case MemberExprClass: { 687 const MemberExpr *m = cast<MemberExpr>(this); 688 if (Ctx.getLangOptions().CPlusPlus) { // C++ [expr.ref]p4: 689 NamedDecl *Member = m->getMemberDecl(); 690 // C++ [expr.ref]p4: 691 // If E2 is declared to have type "reference to T", then E1.E2 692 // is an lvalue. 693 if (ValueDecl *Value = dyn_cast<ValueDecl>(Member)) 694 if (Value->getType()->isReferenceType()) 695 return LV_Valid; 696 697 // -- If E2 is a static data member [...] then E1.E2 is an lvalue. 698 if (isa<VarDecl>(Member) && Member->getDeclContext()->isRecord()) 699 return LV_Valid; 700 701 // -- If E2 is a non-static data member [...]. If E1 is an 702 // lvalue, then E1.E2 is an lvalue. 703 if (isa<FieldDecl>(Member)) 704 return m->isArrow() ? LV_Valid : m->getBase()->isLvalue(Ctx); 705 706 // -- If it refers to a static member function [...], then 707 // E1.E2 is an lvalue. 708 // -- Otherwise, if E1.E2 refers to a non-static member 709 // function [...], then E1.E2 is not an lvalue. 710 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Member)) 711 return Method->isStatic()? LV_Valid : LV_MemberFunction; 712 713 // -- If E2 is a member enumerator [...], the expression E1.E2 714 // is not an lvalue. 715 if (isa<EnumConstantDecl>(Member)) 716 return LV_InvalidExpression; 717 718 // Not an lvalue. 719 return LV_InvalidExpression; 720 } 721 722 // C99 6.5.2.3p4 723 return m->isArrow() ? LV_Valid : m->getBase()->isLvalue(Ctx); 724 } 725 case UnaryOperatorClass: 726 if (cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::Deref) 727 return LV_Valid; // C99 6.5.3p4 728 729 if (cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::Real || 730 cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::Imag || 731 cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::Extension) 732 return cast<UnaryOperator>(this)->getSubExpr()->isLvalue(Ctx); // GNU. 733 734 if (Ctx.getLangOptions().CPlusPlus && // C++ [expr.pre.incr]p1 735 (cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::PreInc || 736 cast<UnaryOperator>(this)->getOpcode() == UnaryOperator::PreDec)) 737 return LV_Valid; 738 break; 739 case ImplicitCastExprClass: 740 return cast<ImplicitCastExpr>(this)->isLvalueCast()? LV_Valid 741 : LV_InvalidExpression; 742 case ParenExprClass: // C99 6.5.1p5 743 return cast<ParenExpr>(this)->getSubExpr()->isLvalue(Ctx); 744 case BinaryOperatorClass: 745 case CompoundAssignOperatorClass: { 746 const BinaryOperator *BinOp = cast<BinaryOperator>(this); 747 748 if (Ctx.getLangOptions().CPlusPlus && // C++ [expr.comma]p1 749 BinOp->getOpcode() == BinaryOperator::Comma) 750 return BinOp->getRHS()->isLvalue(Ctx); 751 752 // C++ [expr.mptr.oper]p6 753 if ((BinOp->getOpcode() == BinaryOperator::PtrMemD || 754 BinOp->getOpcode() == BinaryOperator::PtrMemI) && 755 !BinOp->getType()->isFunctionType()) 756 return BinOp->getLHS()->isLvalue(Ctx); 757 758 if (!BinOp->isAssignmentOp()) 759 return LV_InvalidExpression; 760 761 if (Ctx.getLangOptions().CPlusPlus) 762 // C++ [expr.ass]p1: 763 // The result of an assignment operation [...] is an lvalue. 764 return LV_Valid; 765 766 767 // C99 6.5.16: 768 // An assignment expression [...] is not an lvalue. 769 return LV_InvalidExpression; 770 } 771 case CallExprClass: 772 case CXXOperatorCallExprClass: 773 case CXXMemberCallExprClass: { 774 // C++0x [expr.call]p10 775 // A function call is an lvalue if and only if the result type 776 // is an lvalue reference. 777 QualType ReturnType = cast<CallExpr>(this)->getCallReturnType(); 778 if (ReturnType->isLValueReferenceType()) 779 return LV_Valid; 780 781 break; 782 } 783 case CompoundLiteralExprClass: // C99 6.5.2.5p5 784 return LV_Valid; 785 case ChooseExprClass: 786 // __builtin_choose_expr is an lvalue if the selected operand is. 787 return cast<ChooseExpr>(this)->getChosenSubExpr(Ctx)->isLvalue(Ctx); 788 case ExtVectorElementExprClass: 789 if (cast<ExtVectorElementExpr>(this)->containsDuplicateElements()) 790 return LV_DuplicateVectorComponents; 791 return LV_Valid; 792 case ObjCIvarRefExprClass: // ObjC instance variables are lvalues. 793 return LV_Valid; 794 case ObjCPropertyRefExprClass: // FIXME: check if read-only property. 795 return LV_Valid; 796 case ObjCKVCRefExprClass: // FIXME: check if read-only property. 797 return LV_Valid; 798 case PredefinedExprClass: 799 return LV_Valid; 800 case CXXDefaultArgExprClass: 801 return cast<CXXDefaultArgExpr>(this)->getExpr()->isLvalue(Ctx); 802 case CXXConditionDeclExprClass: 803 return LV_Valid; 804 case CStyleCastExprClass: 805 case CXXFunctionalCastExprClass: 806 case CXXStaticCastExprClass: 807 case CXXDynamicCastExprClass: 808 case CXXReinterpretCastExprClass: 809 case CXXConstCastExprClass: 810 // The result of an explicit cast is an lvalue if the type we are 811 // casting to is an lvalue reference type. See C++ [expr.cast]p1, 812 // C++ [expr.static.cast]p2, C++ [expr.dynamic.cast]p2, 813 // C++ [expr.reinterpret.cast]p1, C++ [expr.const.cast]p1. 814 if (cast<ExplicitCastExpr>(this)->getTypeAsWritten()-> 815 isLValueReferenceType()) 816 return LV_Valid; 817 break; 818 case CXXTypeidExprClass: 819 // C++ 5.2.8p1: The result of a typeid expression is an lvalue of ... 820 return LV_Valid; 821 case CXXBindTemporaryExprClass: 822 return cast<CXXBindTemporaryExpr>(this)->getSubExpr()-> 823 isLvalueInternal(Ctx); 824 case ConditionalOperatorClass: { 825 // Complicated handling is only for C++. 826 if (!Ctx.getLangOptions().CPlusPlus) 827 return LV_InvalidExpression; 828 829 // Sema should have taken care to ensure that a CXXTemporaryObjectExpr is 830 // everywhere there's an object converted to an rvalue. Also, any other 831 // casts should be wrapped by ImplicitCastExprs. There's just the special 832 // case involving throws to work out. 833 const ConditionalOperator *Cond = cast<ConditionalOperator>(this); 834 Expr *True = Cond->getTrueExpr(); 835 Expr *False = Cond->getFalseExpr(); 836 // C++0x 5.16p2 837 // If either the second or the third operand has type (cv) void, [...] 838 // the result [...] is an rvalue. 839 if (True->getType()->isVoidType() || False->getType()->isVoidType()) 840 return LV_InvalidExpression; 841 842 // Both sides must be lvalues for the result to be an lvalue. 843 if (True->isLvalue(Ctx) != LV_Valid || False->isLvalue(Ctx) != LV_Valid) 844 return LV_InvalidExpression; 845 846 // That's it. 847 return LV_Valid; 848 } 849 850 default: 851 break; 852 } 853 return LV_InvalidExpression; 854} 855 856/// isModifiableLvalue - C99 6.3.2.1: an lvalue that does not have array type, 857/// does not have an incomplete type, does not have a const-qualified type, and 858/// if it is a structure or union, does not have any member (including, 859/// recursively, any member or element of all contained aggregates or unions) 860/// with a const-qualified type. 861Expr::isModifiableLvalueResult 862Expr::isModifiableLvalue(ASTContext &Ctx, SourceLocation *Loc) const { 863 isLvalueResult lvalResult = isLvalue(Ctx); 864 865 switch (lvalResult) { 866 case LV_Valid: 867 // C++ 3.10p11: Functions cannot be modified, but pointers to 868 // functions can be modifiable. 869 if (Ctx.getLangOptions().CPlusPlus && TR->isFunctionType()) 870 return MLV_NotObjectType; 871 break; 872 873 case LV_NotObjectType: return MLV_NotObjectType; 874 case LV_IncompleteVoidType: return MLV_IncompleteVoidType; 875 case LV_DuplicateVectorComponents: return MLV_DuplicateVectorComponents; 876 case LV_InvalidExpression: 877 // If the top level is a C-style cast, and the subexpression is a valid 878 // lvalue, then this is probably a use of the old-school "cast as lvalue" 879 // GCC extension. We don't support it, but we want to produce good 880 // diagnostics when it happens so that the user knows why. 881 if (const CStyleCastExpr *CE = dyn_cast<CStyleCastExpr>(IgnoreParens())) { 882 if (CE->getSubExpr()->isLvalue(Ctx) == LV_Valid) { 883 if (Loc) 884 *Loc = CE->getLParenLoc(); 885 return MLV_LValueCast; 886 } 887 } 888 return MLV_InvalidExpression; 889 case LV_MemberFunction: return MLV_MemberFunction; 890 } 891 892 // The following is illegal: 893 // void takeclosure(void (^C)(void)); 894 // void func() { int x = 1; takeclosure(^{ x = 7; }); } 895 // 896 if (isa<BlockDeclRefExpr>(this)) { 897 const BlockDeclRefExpr *BDR = cast<BlockDeclRefExpr>(this); 898 if (!BDR->isByRef() && isa<VarDecl>(BDR->getDecl())) 899 return MLV_NotBlockQualified; 900 } 901 902 QualType CT = Ctx.getCanonicalType(getType()); 903 904 if (CT.isConstQualified()) 905 return MLV_ConstQualified; 906 if (CT->isArrayType()) 907 return MLV_ArrayType; 908 if (CT->isIncompleteType()) 909 return MLV_IncompleteType; 910 911 if (const RecordType *r = CT->getAs<RecordType>()) { 912 if (r->hasConstFields()) 913 return MLV_ConstQualified; 914 } 915 916 // Assigning to an 'implicit' property? 917 else if (isa<ObjCKVCRefExpr>(this)) { 918 const ObjCKVCRefExpr* KVCExpr = cast<ObjCKVCRefExpr>(this); 919 if (KVCExpr->getSetterMethod() == 0) 920 return MLV_NoSetterProperty; 921 } 922 return MLV_Valid; 923} 924 925/// hasGlobalStorage - Return true if this expression has static storage 926/// duration. This means that the address of this expression is a link-time 927/// constant. 928bool Expr::hasGlobalStorage() const { 929 switch (getStmtClass()) { 930 default: 931 return false; 932 case BlockExprClass: 933 return true; 934 case ParenExprClass: 935 return cast<ParenExpr>(this)->getSubExpr()->hasGlobalStorage(); 936 case ImplicitCastExprClass: 937 return cast<ImplicitCastExpr>(this)->getSubExpr()->hasGlobalStorage(); 938 case CompoundLiteralExprClass: 939 return cast<CompoundLiteralExpr>(this)->isFileScope(); 940 case DeclRefExprClass: 941 case QualifiedDeclRefExprClass: { 942 const Decl *D = cast<DeclRefExpr>(this)->getDecl(); 943 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) 944 return VD->hasGlobalStorage(); 945 if (isa<FunctionDecl>(D)) 946 return true; 947 return false; 948 } 949 case MemberExprClass: { 950 const MemberExpr *M = cast<MemberExpr>(this); 951 return !M->isArrow() && M->getBase()->hasGlobalStorage(); 952 } 953 case ArraySubscriptExprClass: 954 return cast<ArraySubscriptExpr>(this)->getBase()->hasGlobalStorage(); 955 case PredefinedExprClass: 956 return true; 957 case CXXDefaultArgExprClass: 958 return cast<CXXDefaultArgExpr>(this)->getExpr()->hasGlobalStorage(); 959 } 960} 961 962/// isOBJCGCCandidate - Check if an expression is objc gc'able. 963/// 964bool Expr::isOBJCGCCandidate(ASTContext &Ctx) const { 965 switch (getStmtClass()) { 966 default: 967 return false; 968 case ObjCIvarRefExprClass: 969 return true; 970 case Expr::UnaryOperatorClass: 971 return cast<UnaryOperator>(this)->getSubExpr()->isOBJCGCCandidate(Ctx); 972 case ParenExprClass: 973 return cast<ParenExpr>(this)->getSubExpr()->isOBJCGCCandidate(Ctx); 974 case ImplicitCastExprClass: 975 return cast<ImplicitCastExpr>(this)->getSubExpr()->isOBJCGCCandidate(Ctx); 976 case CStyleCastExprClass: 977 return cast<CStyleCastExpr>(this)->getSubExpr()->isOBJCGCCandidate(Ctx); 978 case DeclRefExprClass: 979 case QualifiedDeclRefExprClass: { 980 const Decl *D = cast<DeclRefExpr>(this)->getDecl(); 981 if (const VarDecl *VD = dyn_cast<VarDecl>(D)) { 982 if (VD->hasGlobalStorage()) 983 return true; 984 QualType T = VD->getType(); 985 // dereferencing to an object pointer is always a gc'able candidate 986 if (T->isPointerType() && 987 T->getAs<PointerType>()->getPointeeType()->isObjCObjectPointerType()) 988 return true; 989 990 } 991 return false; 992 } 993 case MemberExprClass: { 994 const MemberExpr *M = cast<MemberExpr>(this); 995 return M->getBase()->isOBJCGCCandidate(Ctx); 996 } 997 case ArraySubscriptExprClass: 998 return cast<ArraySubscriptExpr>(this)->getBase()->isOBJCGCCandidate(Ctx); 999 } 1000} 1001Expr* Expr::IgnoreParens() { 1002 Expr* E = this; 1003 while (ParenExpr* P = dyn_cast<ParenExpr>(E)) 1004 E = P->getSubExpr(); 1005 1006 return E; 1007} 1008 1009/// IgnoreParenCasts - Ignore parentheses and casts. Strip off any ParenExpr 1010/// or CastExprs or ImplicitCastExprs, returning their operand. 1011Expr *Expr::IgnoreParenCasts() { 1012 Expr *E = this; 1013 while (true) { 1014 if (ParenExpr *P = dyn_cast<ParenExpr>(E)) 1015 E = P->getSubExpr(); 1016 else if (CastExpr *P = dyn_cast<CastExpr>(E)) 1017 E = P->getSubExpr(); 1018 else 1019 return E; 1020 } 1021} 1022 1023/// IgnoreParenNoopCasts - Ignore parentheses and casts that do not change the 1024/// value (including ptr->int casts of the same size). Strip off any 1025/// ParenExpr or CastExprs, returning their operand. 1026Expr *Expr::IgnoreParenNoopCasts(ASTContext &Ctx) { 1027 Expr *E = this; 1028 while (true) { 1029 if (ParenExpr *P = dyn_cast<ParenExpr>(E)) { 1030 E = P->getSubExpr(); 1031 continue; 1032 } 1033 1034 if (CastExpr *P = dyn_cast<CastExpr>(E)) { 1035 // We ignore integer <-> casts that are of the same width, ptr<->ptr and 1036 // ptr<->int casts of the same width. We also ignore all identify casts. 1037 Expr *SE = P->getSubExpr(); 1038 1039 if (Ctx.hasSameUnqualifiedType(E->getType(), SE->getType())) { 1040 E = SE; 1041 continue; 1042 } 1043 1044 if ((E->getType()->isPointerType() || E->getType()->isIntegralType()) && 1045 (SE->getType()->isPointerType() || SE->getType()->isIntegralType()) && 1046 Ctx.getTypeSize(E->getType()) == Ctx.getTypeSize(SE->getType())) { 1047 E = SE; 1048 continue; 1049 } 1050 } 1051 1052 return E; 1053 } 1054} 1055 1056 1057/// hasAnyTypeDependentArguments - Determines if any of the expressions 1058/// in Exprs is type-dependent. 1059bool Expr::hasAnyTypeDependentArguments(Expr** Exprs, unsigned NumExprs) { 1060 for (unsigned I = 0; I < NumExprs; ++I) 1061 if (Exprs[I]->isTypeDependent()) 1062 return true; 1063 1064 return false; 1065} 1066 1067/// hasAnyValueDependentArguments - Determines if any of the expressions 1068/// in Exprs is value-dependent. 1069bool Expr::hasAnyValueDependentArguments(Expr** Exprs, unsigned NumExprs) { 1070 for (unsigned I = 0; I < NumExprs; ++I) 1071 if (Exprs[I]->isValueDependent()) 1072 return true; 1073 1074 return false; 1075} 1076 1077bool Expr::isConstantInitializer(ASTContext &Ctx) const { 1078 // This function is attempting whether an expression is an initializer 1079 // which can be evaluated at compile-time. isEvaluatable handles most 1080 // of the cases, but it can't deal with some initializer-specific 1081 // expressions, and it can't deal with aggregates; we deal with those here, 1082 // and fall back to isEvaluatable for the other cases. 1083 1084 // FIXME: This function assumes the variable being assigned to 1085 // isn't a reference type! 1086 1087 switch (getStmtClass()) { 1088 default: break; 1089 case StringLiteralClass: 1090 case ObjCStringLiteralClass: 1091 case ObjCEncodeExprClass: 1092 return true; 1093 case CompoundLiteralExprClass: { 1094 // This handles gcc's extension that allows global initializers like 1095 // "struct x {int x;} x = (struct x) {};". 1096 // FIXME: This accepts other cases it shouldn't! 1097 const Expr *Exp = cast<CompoundLiteralExpr>(this)->getInitializer(); 1098 return Exp->isConstantInitializer(Ctx); 1099 } 1100 case InitListExprClass: { 1101 // FIXME: This doesn't deal with fields with reference types correctly. 1102 // FIXME: This incorrectly allows pointers cast to integers to be assigned 1103 // to bitfields. 1104 const InitListExpr *Exp = cast<InitListExpr>(this); 1105 unsigned numInits = Exp->getNumInits(); 1106 for (unsigned i = 0; i < numInits; i++) { 1107 if (!Exp->getInit(i)->isConstantInitializer(Ctx)) 1108 return false; 1109 } 1110 return true; 1111 } 1112 case ImplicitValueInitExprClass: 1113 return true; 1114 case ParenExprClass: { 1115 return cast<ParenExpr>(this)->getSubExpr()->isConstantInitializer(Ctx); 1116 } 1117 case UnaryOperatorClass: { 1118 const UnaryOperator* Exp = cast<UnaryOperator>(this); 1119 if (Exp->getOpcode() == UnaryOperator::Extension) 1120 return Exp->getSubExpr()->isConstantInitializer(Ctx); 1121 break; 1122 } 1123 case ImplicitCastExprClass: 1124 case CStyleCastExprClass: 1125 // Handle casts with a destination that's a struct or union; this 1126 // deals with both the gcc no-op struct cast extension and the 1127 // cast-to-union extension. 1128 if (getType()->isRecordType()) 1129 return cast<CastExpr>(this)->getSubExpr()->isConstantInitializer(Ctx); 1130 break; 1131 } 1132 return isEvaluatable(Ctx); 1133} 1134 1135/// isIntegerConstantExpr - this recursive routine will test if an expression is 1136/// an integer constant expression. 1137 1138/// FIXME: Pass up a reason why! Invalid operation in i-c-e, division by zero, 1139/// comma, etc 1140/// 1141/// FIXME: Handle offsetof. Two things to do: Handle GCC's __builtin_offsetof 1142/// to support gcc 4.0+ and handle the idiom GCC recognizes with a null pointer 1143/// cast+dereference. 1144 1145// CheckICE - This function does the fundamental ICE checking: the returned 1146// ICEDiag contains a Val of 0, 1, or 2, and a possibly null SourceLocation. 1147// Note that to reduce code duplication, this helper does no evaluation 1148// itself; the caller checks whether the expression is evaluatable, and 1149// in the rare cases where CheckICE actually cares about the evaluated 1150// value, it calls into Evalute. 1151// 1152// Meanings of Val: 1153// 0: This expression is an ICE if it can be evaluated by Evaluate. 1154// 1: This expression is not an ICE, but if it isn't evaluated, it's 1155// a legal subexpression for an ICE. This return value is used to handle 1156// the comma operator in C99 mode. 1157// 2: This expression is not an ICE, and is not a legal subexpression for one. 1158 1159struct ICEDiag { 1160 unsigned Val; 1161 SourceLocation Loc; 1162 1163 public: 1164 ICEDiag(unsigned v, SourceLocation l) : Val(v), Loc(l) {} 1165 ICEDiag() : Val(0) {} 1166}; 1167 1168ICEDiag NoDiag() { return ICEDiag(); } 1169 1170static ICEDiag CheckEvalInICE(const Expr* E, ASTContext &Ctx) { 1171 Expr::EvalResult EVResult; 1172 if (!E->Evaluate(EVResult, Ctx) || EVResult.HasSideEffects || 1173 !EVResult.Val.isInt()) { 1174 return ICEDiag(2, E->getLocStart()); 1175 } 1176 return NoDiag(); 1177} 1178 1179static ICEDiag CheckICE(const Expr* E, ASTContext &Ctx) { 1180 assert(!E->isValueDependent() && "Should not see value dependent exprs!"); 1181 if (!E->getType()->isIntegralType()) { 1182 return ICEDiag(2, E->getLocStart()); 1183 } 1184 1185 switch (E->getStmtClass()) { 1186 default: 1187 return ICEDiag(2, E->getLocStart()); 1188 case Expr::ParenExprClass: 1189 return CheckICE(cast<ParenExpr>(E)->getSubExpr(), Ctx); 1190 case Expr::IntegerLiteralClass: 1191 case Expr::CharacterLiteralClass: 1192 case Expr::CXXBoolLiteralExprClass: 1193 case Expr::CXXZeroInitValueExprClass: 1194 case Expr::TypesCompatibleExprClass: 1195 case Expr::UnaryTypeTraitExprClass: 1196 return NoDiag(); 1197 case Expr::CallExprClass: 1198 case Expr::CXXOperatorCallExprClass: { 1199 const CallExpr *CE = cast<CallExpr>(E); 1200 if (CE->isBuiltinCall(Ctx)) 1201 return CheckEvalInICE(E, Ctx); 1202 return ICEDiag(2, E->getLocStart()); 1203 } 1204 case Expr::DeclRefExprClass: 1205 case Expr::QualifiedDeclRefExprClass: 1206 if (isa<EnumConstantDecl>(cast<DeclRefExpr>(E)->getDecl())) 1207 return NoDiag(); 1208 if (Ctx.getLangOptions().CPlusPlus && 1209 E->getType().getCVRQualifiers() == QualType::Const) { 1210 // C++ 7.1.5.1p2 1211 // A variable of non-volatile const-qualified integral or enumeration 1212 // type initialized by an ICE can be used in ICEs. 1213 if (const VarDecl *Dcl = 1214 dyn_cast<VarDecl>(cast<DeclRefExpr>(E)->getDecl())) { 1215 if (Dcl->isInitKnownICE()) { 1216 // We have already checked whether this subexpression is an 1217 // integral constant expression. 1218 if (Dcl->isInitICE()) 1219 return NoDiag(); 1220 else 1221 return ICEDiag(2, E->getLocStart()); 1222 } 1223 1224 if (const Expr *Init = Dcl->getInit()) { 1225 ICEDiag Result = CheckICE(Init, Ctx); 1226 // Cache the result of the ICE test. 1227 Dcl->setInitKnownICE(Ctx, Result.Val == 0); 1228 return Result; 1229 } 1230 } 1231 } 1232 return ICEDiag(2, E->getLocStart()); 1233 case Expr::UnaryOperatorClass: { 1234 const UnaryOperator *Exp = cast<UnaryOperator>(E); 1235 switch (Exp->getOpcode()) { 1236 default: 1237 return ICEDiag(2, E->getLocStart()); 1238 case UnaryOperator::Extension: 1239 case UnaryOperator::LNot: 1240 case UnaryOperator::Plus: 1241 case UnaryOperator::Minus: 1242 case UnaryOperator::Not: 1243 case UnaryOperator::Real: 1244 case UnaryOperator::Imag: 1245 return CheckICE(Exp->getSubExpr(), Ctx); 1246 case UnaryOperator::OffsetOf: 1247 // Note that per C99, offsetof must be an ICE. And AFAIK, using 1248 // Evaluate matches the proposed gcc behavior for cases like 1249 // "offsetof(struct s{int x[4];}, x[!.0])". This doesn't affect 1250 // compliance: we should warn earlier for offsetof expressions with 1251 // array subscripts that aren't ICEs, and if the array subscripts 1252 // are ICEs, the value of the offsetof must be an integer constant. 1253 return CheckEvalInICE(E, Ctx); 1254 } 1255 } 1256 case Expr::SizeOfAlignOfExprClass: { 1257 const SizeOfAlignOfExpr *Exp = cast<SizeOfAlignOfExpr>(E); 1258 if (Exp->isSizeOf() && Exp->getTypeOfArgument()->isVariableArrayType()) 1259 return ICEDiag(2, E->getLocStart()); 1260 return NoDiag(); 1261 } 1262 case Expr::BinaryOperatorClass: { 1263 const BinaryOperator *Exp = cast<BinaryOperator>(E); 1264 switch (Exp->getOpcode()) { 1265 default: 1266 return ICEDiag(2, E->getLocStart()); 1267 case BinaryOperator::Mul: 1268 case BinaryOperator::Div: 1269 case BinaryOperator::Rem: 1270 case BinaryOperator::Add: 1271 case BinaryOperator::Sub: 1272 case BinaryOperator::Shl: 1273 case BinaryOperator::Shr: 1274 case BinaryOperator::LT: 1275 case BinaryOperator::GT: 1276 case BinaryOperator::LE: 1277 case BinaryOperator::GE: 1278 case BinaryOperator::EQ: 1279 case BinaryOperator::NE: 1280 case BinaryOperator::And: 1281 case BinaryOperator::Xor: 1282 case BinaryOperator::Or: 1283 case BinaryOperator::Comma: { 1284 ICEDiag LHSResult = CheckICE(Exp->getLHS(), Ctx); 1285 ICEDiag RHSResult = CheckICE(Exp->getRHS(), Ctx); 1286 if (Exp->getOpcode() == BinaryOperator::Div || 1287 Exp->getOpcode() == BinaryOperator::Rem) { 1288 // Evaluate gives an error for undefined Div/Rem, so make sure 1289 // we don't evaluate one. 1290 if (LHSResult.Val != 2 && RHSResult.Val != 2) { 1291 llvm::APSInt REval = Exp->getRHS()->EvaluateAsInt(Ctx); 1292 if (REval == 0) 1293 return ICEDiag(1, E->getLocStart()); 1294 if (REval.isSigned() && REval.isAllOnesValue()) { 1295 llvm::APSInt LEval = Exp->getLHS()->EvaluateAsInt(Ctx); 1296 if (LEval.isMinSignedValue()) 1297 return ICEDiag(1, E->getLocStart()); 1298 } 1299 } 1300 } 1301 if (Exp->getOpcode() == BinaryOperator::Comma) { 1302 if (Ctx.getLangOptions().C99) { 1303 // C99 6.6p3 introduces a strange edge case: comma can be in an ICE 1304 // if it isn't evaluated. 1305 if (LHSResult.Val == 0 && RHSResult.Val == 0) 1306 return ICEDiag(1, E->getLocStart()); 1307 } else { 1308 // In both C89 and C++, commas in ICEs are illegal. 1309 return ICEDiag(2, E->getLocStart()); 1310 } 1311 } 1312 if (LHSResult.Val >= RHSResult.Val) 1313 return LHSResult; 1314 return RHSResult; 1315 } 1316 case BinaryOperator::LAnd: 1317 case BinaryOperator::LOr: { 1318 ICEDiag LHSResult = CheckICE(Exp->getLHS(), Ctx); 1319 ICEDiag RHSResult = CheckICE(Exp->getRHS(), Ctx); 1320 if (LHSResult.Val == 0 && RHSResult.Val == 1) { 1321 // Rare case where the RHS has a comma "side-effect"; we need 1322 // to actually check the condition to see whether the side 1323 // with the comma is evaluated. 1324 if ((Exp->getOpcode() == BinaryOperator::LAnd) != 1325 (Exp->getLHS()->EvaluateAsInt(Ctx) == 0)) 1326 return RHSResult; 1327 return NoDiag(); 1328 } 1329 1330 if (LHSResult.Val >= RHSResult.Val) 1331 return LHSResult; 1332 return RHSResult; 1333 } 1334 } 1335 } 1336 case Expr::ImplicitCastExprClass: 1337 case Expr::CStyleCastExprClass: 1338 case Expr::CXXFunctionalCastExprClass: { 1339 const Expr *SubExpr = cast<CastExpr>(E)->getSubExpr(); 1340 if (SubExpr->getType()->isIntegralType()) 1341 return CheckICE(SubExpr, Ctx); 1342 if (isa<FloatingLiteral>(SubExpr->IgnoreParens())) 1343 return NoDiag(); 1344 return ICEDiag(2, E->getLocStart()); 1345 } 1346 case Expr::ConditionalOperatorClass: { 1347 const ConditionalOperator *Exp = cast<ConditionalOperator>(E); 1348 // If the condition (ignoring parens) is a __builtin_constant_p call, 1349 // then only the true side is actually considered in an integer constant 1350 // expression, and it is fully evaluated. This is an important GNU 1351 // extension. See GCC PR38377 for discussion. 1352 if (const CallExpr *CallCE = dyn_cast<CallExpr>(Exp->getCond()->IgnoreParenCasts())) 1353 if (CallCE->isBuiltinCall(Ctx) == Builtin::BI__builtin_constant_p) { 1354 Expr::EvalResult EVResult; 1355 if (!E->Evaluate(EVResult, Ctx) || EVResult.HasSideEffects || 1356 !EVResult.Val.isInt()) { 1357 return ICEDiag(2, E->getLocStart()); 1358 } 1359 return NoDiag(); 1360 } 1361 ICEDiag CondResult = CheckICE(Exp->getCond(), Ctx); 1362 ICEDiag TrueResult = CheckICE(Exp->getTrueExpr(), Ctx); 1363 ICEDiag FalseResult = CheckICE(Exp->getFalseExpr(), Ctx); 1364 if (CondResult.Val == 2) 1365 return CondResult; 1366 if (TrueResult.Val == 2) 1367 return TrueResult; 1368 if (FalseResult.Val == 2) 1369 return FalseResult; 1370 if (CondResult.Val == 1) 1371 return CondResult; 1372 if (TrueResult.Val == 0 && FalseResult.Val == 0) 1373 return NoDiag(); 1374 // Rare case where the diagnostics depend on which side is evaluated 1375 // Note that if we get here, CondResult is 0, and at least one of 1376 // TrueResult and FalseResult is non-zero. 1377 if (Exp->getCond()->EvaluateAsInt(Ctx) == 0) { 1378 return FalseResult; 1379 } 1380 return TrueResult; 1381 } 1382 case Expr::CXXDefaultArgExprClass: 1383 return CheckICE(cast<CXXDefaultArgExpr>(E)->getExpr(), Ctx); 1384 case Expr::ChooseExprClass: { 1385 return CheckICE(cast<ChooseExpr>(E)->getChosenSubExpr(Ctx), Ctx); 1386 } 1387 } 1388} 1389 1390bool Expr::isIntegerConstantExpr(llvm::APSInt &Result, ASTContext &Ctx, 1391 SourceLocation *Loc, bool isEvaluated) const { 1392 ICEDiag d = CheckICE(this, Ctx); 1393 if (d.Val != 0) { 1394 if (Loc) *Loc = d.Loc; 1395 return false; 1396 } 1397 EvalResult EvalResult; 1398 if (!Evaluate(EvalResult, Ctx)) 1399 assert(0 && "ICE cannot be evaluated!"); 1400 assert(!EvalResult.HasSideEffects && "ICE with side effects!"); 1401 assert(EvalResult.Val.isInt() && "ICE that isn't integer!"); 1402 Result = EvalResult.Val.getInt(); 1403 return true; 1404} 1405 1406/// isNullPointerConstant - C99 6.3.2.3p3 - Return true if this is either an 1407/// integer constant expression with the value zero, or if this is one that is 1408/// cast to void*. 1409bool Expr::isNullPointerConstant(ASTContext &Ctx) const 1410{ 1411 // Strip off a cast to void*, if it exists. Except in C++. 1412 if (const ExplicitCastExpr *CE = dyn_cast<ExplicitCastExpr>(this)) { 1413 if (!Ctx.getLangOptions().CPlusPlus) { 1414 // Check that it is a cast to void*. 1415 if (const PointerType *PT = CE->getType()->getAs<PointerType>()) { 1416 QualType Pointee = PT->getPointeeType(); 1417 if (Pointee.getCVRQualifiers() == 0 && 1418 Pointee->isVoidType() && // to void* 1419 CE->getSubExpr()->getType()->isIntegerType()) // from int. 1420 return CE->getSubExpr()->isNullPointerConstant(Ctx); 1421 } 1422 } 1423 } else if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(this)) { 1424 // Ignore the ImplicitCastExpr type entirely. 1425 return ICE->getSubExpr()->isNullPointerConstant(Ctx); 1426 } else if (const ParenExpr *PE = dyn_cast<ParenExpr>(this)) { 1427 // Accept ((void*)0) as a null pointer constant, as many other 1428 // implementations do. 1429 return PE->getSubExpr()->isNullPointerConstant(Ctx); 1430 } else if (const CXXDefaultArgExpr *DefaultArg 1431 = dyn_cast<CXXDefaultArgExpr>(this)) { 1432 // See through default argument expressions 1433 return DefaultArg->getExpr()->isNullPointerConstant(Ctx); 1434 } else if (isa<GNUNullExpr>(this)) { 1435 // The GNU __null extension is always a null pointer constant. 1436 return true; 1437 } 1438 1439 // C++0x nullptr_t is always a null pointer constant. 1440 if (getType()->isNullPtrType()) 1441 return true; 1442 1443 // This expression must be an integer type. 1444 if (!getType()->isIntegerType()) 1445 return false; 1446 1447 // If we have an integer constant expression, we need to *evaluate* it and 1448 // test for the value 0. 1449 llvm::APSInt Result; 1450 return isIntegerConstantExpr(Result, Ctx) && Result == 0; 1451} 1452 1453FieldDecl *Expr::getBitField() { 1454 Expr *E = this->IgnoreParens(); 1455 1456 if (MemberExpr *MemRef = dyn_cast<MemberExpr>(E)) 1457 if (FieldDecl *Field = dyn_cast<FieldDecl>(MemRef->getMemberDecl())) 1458 if (Field->isBitField()) 1459 return Field; 1460 1461 if (BinaryOperator *BinOp = dyn_cast<BinaryOperator>(E)) 1462 if (BinOp->isAssignmentOp() && BinOp->getLHS()) 1463 return BinOp->getLHS()->getBitField(); 1464 1465 return 0; 1466} 1467 1468/// isArrow - Return true if the base expression is a pointer to vector, 1469/// return false if the base expression is a vector. 1470bool ExtVectorElementExpr::isArrow() const { 1471 return getBase()->getType()->isPointerType(); 1472} 1473 1474unsigned ExtVectorElementExpr::getNumElements() const { 1475 if (const VectorType *VT = getType()->getAsVectorType()) 1476 return VT->getNumElements(); 1477 return 1; 1478} 1479 1480/// containsDuplicateElements - Return true if any element access is repeated. 1481bool ExtVectorElementExpr::containsDuplicateElements() const { 1482 const char *compStr = Accessor->getName(); 1483 unsigned length = Accessor->getLength(); 1484 1485 // Halving swizzles do not contain duplicate elements. 1486 if (!strcmp(compStr, "hi") || !strcmp(compStr, "lo") || 1487 !strcmp(compStr, "even") || !strcmp(compStr, "odd")) 1488 return false; 1489 1490 // Advance past s-char prefix on hex swizzles. 1491 if (*compStr == 's' || *compStr == 'S') { 1492 compStr++; 1493 length--; 1494 } 1495 1496 for (unsigned i = 0; i != length-1; i++) { 1497 const char *s = compStr+i; 1498 for (const char c = *s++; *s; s++) 1499 if (c == *s) 1500 return true; 1501 } 1502 return false; 1503} 1504 1505/// getEncodedElementAccess - We encode the fields as a llvm ConstantArray. 1506void ExtVectorElementExpr::getEncodedElementAccess( 1507 llvm::SmallVectorImpl<unsigned> &Elts) const { 1508 const char *compStr = Accessor->getName(); 1509 if (*compStr == 's' || *compStr == 'S') 1510 compStr++; 1511 1512 bool isHi = !strcmp(compStr, "hi"); 1513 bool isLo = !strcmp(compStr, "lo"); 1514 bool isEven = !strcmp(compStr, "even"); 1515 bool isOdd = !strcmp(compStr, "odd"); 1516 1517 for (unsigned i = 0, e = getNumElements(); i != e; ++i) { 1518 uint64_t Index; 1519 1520 if (isHi) 1521 Index = e + i; 1522 else if (isLo) 1523 Index = i; 1524 else if (isEven) 1525 Index = 2 * i; 1526 else if (isOdd) 1527 Index = 2 * i + 1; 1528 else 1529 Index = ExtVectorType::getAccessorIdx(compStr[i]); 1530 1531 Elts.push_back(Index); 1532 } 1533} 1534 1535// constructor for instance messages. 1536ObjCMessageExpr::ObjCMessageExpr(Expr *receiver, Selector selInfo, 1537 QualType retType, ObjCMethodDecl *mproto, 1538 SourceLocation LBrac, SourceLocation RBrac, 1539 Expr **ArgExprs, unsigned nargs) 1540 : Expr(ObjCMessageExprClass, retType), SelName(selInfo), 1541 MethodProto(mproto) { 1542 NumArgs = nargs; 1543 SubExprs = new Stmt*[NumArgs+1]; 1544 SubExprs[RECEIVER] = receiver; 1545 if (NumArgs) { 1546 for (unsigned i = 0; i != NumArgs; ++i) 1547 SubExprs[i+ARGS_START] = static_cast<Expr *>(ArgExprs[i]); 1548 } 1549 LBracloc = LBrac; 1550 RBracloc = RBrac; 1551} 1552 1553// constructor for class messages. 1554// FIXME: clsName should be typed to ObjCInterfaceType 1555ObjCMessageExpr::ObjCMessageExpr(IdentifierInfo *clsName, Selector selInfo, 1556 QualType retType, ObjCMethodDecl *mproto, 1557 SourceLocation LBrac, SourceLocation RBrac, 1558 Expr **ArgExprs, unsigned nargs) 1559 : Expr(ObjCMessageExprClass, retType), SelName(selInfo), 1560 MethodProto(mproto) { 1561 NumArgs = nargs; 1562 SubExprs = new Stmt*[NumArgs+1]; 1563 SubExprs[RECEIVER] = (Expr*) ((uintptr_t) clsName | IsClsMethDeclUnknown); 1564 if (NumArgs) { 1565 for (unsigned i = 0; i != NumArgs; ++i) 1566 SubExprs[i+ARGS_START] = static_cast<Expr *>(ArgExprs[i]); 1567 } 1568 LBracloc = LBrac; 1569 RBracloc = RBrac; 1570} 1571 1572// constructor for class messages. 1573ObjCMessageExpr::ObjCMessageExpr(ObjCInterfaceDecl *cls, Selector selInfo, 1574 QualType retType, ObjCMethodDecl *mproto, 1575 SourceLocation LBrac, SourceLocation RBrac, 1576 Expr **ArgExprs, unsigned nargs) 1577: Expr(ObjCMessageExprClass, retType), SelName(selInfo), 1578MethodProto(mproto) { 1579 NumArgs = nargs; 1580 SubExprs = new Stmt*[NumArgs+1]; 1581 SubExprs[RECEIVER] = (Expr*) ((uintptr_t) cls | IsClsMethDeclKnown); 1582 if (NumArgs) { 1583 for (unsigned i = 0; i != NumArgs; ++i) 1584 SubExprs[i+ARGS_START] = static_cast<Expr *>(ArgExprs[i]); 1585 } 1586 LBracloc = LBrac; 1587 RBracloc = RBrac; 1588} 1589 1590ObjCMessageExpr::ClassInfo ObjCMessageExpr::getClassInfo() const { 1591 uintptr_t x = (uintptr_t) SubExprs[RECEIVER]; 1592 switch (x & Flags) { 1593 default: 1594 assert(false && "Invalid ObjCMessageExpr."); 1595 case IsInstMeth: 1596 return ClassInfo(0, 0); 1597 case IsClsMethDeclUnknown: 1598 return ClassInfo(0, (IdentifierInfo*) (x & ~Flags)); 1599 case IsClsMethDeclKnown: { 1600 ObjCInterfaceDecl* D = (ObjCInterfaceDecl*) (x & ~Flags); 1601 return ClassInfo(D, D->getIdentifier()); 1602 } 1603 } 1604} 1605 1606void ObjCMessageExpr::setClassInfo(const ObjCMessageExpr::ClassInfo &CI) { 1607 if (CI.first == 0 && CI.second == 0) 1608 SubExprs[RECEIVER] = (Expr*)((uintptr_t)0 | IsInstMeth); 1609 else if (CI.first == 0) 1610 SubExprs[RECEIVER] = (Expr*)((uintptr_t)CI.second | IsClsMethDeclUnknown); 1611 else 1612 SubExprs[RECEIVER] = (Expr*)((uintptr_t)CI.first | IsClsMethDeclKnown); 1613} 1614 1615 1616bool ChooseExpr::isConditionTrue(ASTContext &C) const { 1617 return getCond()->EvaluateAsInt(C) != 0; 1618} 1619 1620void ShuffleVectorExpr::setExprs(ASTContext &C, Expr ** Exprs, 1621 unsigned NumExprs) { 1622 if (SubExprs) C.Deallocate(SubExprs); 1623 1624 SubExprs = new (C) Stmt* [NumExprs]; 1625 this->NumExprs = NumExprs; 1626 memcpy(SubExprs, Exprs, sizeof(Expr *) * NumExprs); 1627} 1628 1629void ShuffleVectorExpr::DoDestroy(ASTContext& C) { 1630 DestroyChildren(C); 1631 if (SubExprs) C.Deallocate(SubExprs); 1632 this->~ShuffleVectorExpr(); 1633 C.Deallocate(this); 1634} 1635 1636void SizeOfAlignOfExpr::DoDestroy(ASTContext& C) { 1637 // Override default behavior of traversing children. If this has a type 1638 // operand and the type is a variable-length array, the child iteration 1639 // will iterate over the size expression. However, this expression belongs 1640 // to the type, not to this, so we don't want to delete it. 1641 // We still want to delete this expression. 1642 if (isArgumentType()) { 1643 this->~SizeOfAlignOfExpr(); 1644 C.Deallocate(this); 1645 } 1646 else 1647 Expr::DoDestroy(C); 1648} 1649 1650//===----------------------------------------------------------------------===// 1651// DesignatedInitExpr 1652//===----------------------------------------------------------------------===// 1653 1654IdentifierInfo *DesignatedInitExpr::Designator::getFieldName() { 1655 assert(Kind == FieldDesignator && "Only valid on a field designator"); 1656 if (Field.NameOrField & 0x01) 1657 return reinterpret_cast<IdentifierInfo *>(Field.NameOrField&~0x01); 1658 else 1659 return getField()->getIdentifier(); 1660} 1661 1662DesignatedInitExpr::DesignatedInitExpr(QualType Ty, unsigned NumDesignators, 1663 const Designator *Designators, 1664 SourceLocation EqualOrColonLoc, 1665 bool GNUSyntax, 1666 Expr **IndexExprs, 1667 unsigned NumIndexExprs, 1668 Expr *Init) 1669 : Expr(DesignatedInitExprClass, Ty, 1670 Init->isTypeDependent(), Init->isValueDependent()), 1671 EqualOrColonLoc(EqualOrColonLoc), GNUSyntax(GNUSyntax), 1672 NumDesignators(NumDesignators), NumSubExprs(NumIndexExprs + 1) { 1673 this->Designators = new Designator[NumDesignators]; 1674 1675 // Record the initializer itself. 1676 child_iterator Child = child_begin(); 1677 *Child++ = Init; 1678 1679 // Copy the designators and their subexpressions, computing 1680 // value-dependence along the way. 1681 unsigned IndexIdx = 0; 1682 for (unsigned I = 0; I != NumDesignators; ++I) { 1683 this->Designators[I] = Designators[I]; 1684 1685 if (this->Designators[I].isArrayDesignator()) { 1686 // Compute type- and value-dependence. 1687 Expr *Index = IndexExprs[IndexIdx]; 1688 ValueDependent = ValueDependent || 1689 Index->isTypeDependent() || Index->isValueDependent(); 1690 1691 // Copy the index expressions into permanent storage. 1692 *Child++ = IndexExprs[IndexIdx++]; 1693 } else if (this->Designators[I].isArrayRangeDesignator()) { 1694 // Compute type- and value-dependence. 1695 Expr *Start = IndexExprs[IndexIdx]; 1696 Expr *End = IndexExprs[IndexIdx + 1]; 1697 ValueDependent = ValueDependent || 1698 Start->isTypeDependent() || Start->isValueDependent() || 1699 End->isTypeDependent() || End->isValueDependent(); 1700 1701 // Copy the start/end expressions into permanent storage. 1702 *Child++ = IndexExprs[IndexIdx++]; 1703 *Child++ = IndexExprs[IndexIdx++]; 1704 } 1705 } 1706 1707 assert(IndexIdx == NumIndexExprs && "Wrong number of index expressions"); 1708} 1709 1710DesignatedInitExpr * 1711DesignatedInitExpr::Create(ASTContext &C, Designator *Designators, 1712 unsigned NumDesignators, 1713 Expr **IndexExprs, unsigned NumIndexExprs, 1714 SourceLocation ColonOrEqualLoc, 1715 bool UsesColonSyntax, Expr *Init) { 1716 void *Mem = C.Allocate(sizeof(DesignatedInitExpr) + 1717 sizeof(Stmt *) * (NumIndexExprs + 1), 8); 1718 return new (Mem) DesignatedInitExpr(C.VoidTy, NumDesignators, Designators, 1719 ColonOrEqualLoc, UsesColonSyntax, 1720 IndexExprs, NumIndexExprs, Init); 1721} 1722 1723DesignatedInitExpr *DesignatedInitExpr::CreateEmpty(ASTContext &C, 1724 unsigned NumIndexExprs) { 1725 void *Mem = C.Allocate(sizeof(DesignatedInitExpr) + 1726 sizeof(Stmt *) * (NumIndexExprs + 1), 8); 1727 return new (Mem) DesignatedInitExpr(NumIndexExprs + 1); 1728} 1729 1730void DesignatedInitExpr::setDesignators(const Designator *Desigs, 1731 unsigned NumDesigs) { 1732 if (Designators) 1733 delete [] Designators; 1734 1735 Designators = new Designator[NumDesigs]; 1736 NumDesignators = NumDesigs; 1737 for (unsigned I = 0; I != NumDesigs; ++I) 1738 Designators[I] = Desigs[I]; 1739} 1740 1741SourceRange DesignatedInitExpr::getSourceRange() const { 1742 SourceLocation StartLoc; 1743 Designator &First = 1744 *const_cast<DesignatedInitExpr*>(this)->designators_begin(); 1745 if (First.isFieldDesignator()) { 1746 if (GNUSyntax) 1747 StartLoc = SourceLocation::getFromRawEncoding(First.Field.FieldLoc); 1748 else 1749 StartLoc = SourceLocation::getFromRawEncoding(First.Field.DotLoc); 1750 } else 1751 StartLoc = 1752 SourceLocation::getFromRawEncoding(First.ArrayOrRange.LBracketLoc); 1753 return SourceRange(StartLoc, getInit()->getSourceRange().getEnd()); 1754} 1755 1756Expr *DesignatedInitExpr::getArrayIndex(const Designator& D) { 1757 assert(D.Kind == Designator::ArrayDesignator && "Requires array designator"); 1758 char* Ptr = static_cast<char*>(static_cast<void *>(this)); 1759 Ptr += sizeof(DesignatedInitExpr); 1760 Stmt **SubExprs = reinterpret_cast<Stmt**>(reinterpret_cast<void**>(Ptr)); 1761 return cast<Expr>(*(SubExprs + D.ArrayOrRange.Index + 1)); 1762} 1763 1764Expr *DesignatedInitExpr::getArrayRangeStart(const Designator& D) { 1765 assert(D.Kind == Designator::ArrayRangeDesignator && 1766 "Requires array range designator"); 1767 char* Ptr = static_cast<char*>(static_cast<void *>(this)); 1768 Ptr += sizeof(DesignatedInitExpr); 1769 Stmt **SubExprs = reinterpret_cast<Stmt**>(reinterpret_cast<void**>(Ptr)); 1770 return cast<Expr>(*(SubExprs + D.ArrayOrRange.Index + 1)); 1771} 1772 1773Expr *DesignatedInitExpr::getArrayRangeEnd(const Designator& D) { 1774 assert(D.Kind == Designator::ArrayRangeDesignator && 1775 "Requires array range designator"); 1776 char* Ptr = static_cast<char*>(static_cast<void *>(this)); 1777 Ptr += sizeof(DesignatedInitExpr); 1778 Stmt **SubExprs = reinterpret_cast<Stmt**>(reinterpret_cast<void**>(Ptr)); 1779 return cast<Expr>(*(SubExprs + D.ArrayOrRange.Index + 2)); 1780} 1781 1782/// \brief Replaces the designator at index @p Idx with the series 1783/// of designators in [First, Last). 1784void DesignatedInitExpr::ExpandDesignator(unsigned Idx, 1785 const Designator *First, 1786 const Designator *Last) { 1787 unsigned NumNewDesignators = Last - First; 1788 if (NumNewDesignators == 0) { 1789 std::copy_backward(Designators + Idx + 1, 1790 Designators + NumDesignators, 1791 Designators + Idx); 1792 --NumNewDesignators; 1793 return; 1794 } else if (NumNewDesignators == 1) { 1795 Designators[Idx] = *First; 1796 return; 1797 } 1798 1799 Designator *NewDesignators 1800 = new Designator[NumDesignators - 1 + NumNewDesignators]; 1801 std::copy(Designators, Designators + Idx, NewDesignators); 1802 std::copy(First, Last, NewDesignators + Idx); 1803 std::copy(Designators + Idx + 1, Designators + NumDesignators, 1804 NewDesignators + Idx + NumNewDesignators); 1805 delete [] Designators; 1806 Designators = NewDesignators; 1807 NumDesignators = NumDesignators - 1 + NumNewDesignators; 1808} 1809 1810void DesignatedInitExpr::DoDestroy(ASTContext &C) { 1811 delete [] Designators; 1812 Expr::DoDestroy(C); 1813} 1814 1815ParenListExpr::ParenListExpr(ASTContext& C, SourceLocation lparenloc, 1816 Expr **exprs, unsigned nexprs, 1817 SourceLocation rparenloc) 1818: Expr(ParenListExprClass, QualType(), 1819 hasAnyTypeDependentArguments(exprs, nexprs), 1820 hasAnyValueDependentArguments(exprs, nexprs)), 1821 NumExprs(nexprs), LParenLoc(lparenloc), RParenLoc(rparenloc) { 1822 1823 Exprs = new (C) Stmt*[nexprs]; 1824 for (unsigned i = 0; i != nexprs; ++i) 1825 Exprs[i] = exprs[i]; 1826} 1827 1828void ParenListExpr::DoDestroy(ASTContext& C) { 1829 DestroyChildren(C); 1830 if (Exprs) C.Deallocate(Exprs); 1831 this->~ParenListExpr(); 1832 C.Deallocate(this); 1833} 1834 1835//===----------------------------------------------------------------------===// 1836// ExprIterator. 1837//===----------------------------------------------------------------------===// 1838 1839Expr* ExprIterator::operator[](size_t idx) { return cast<Expr>(I[idx]); } 1840Expr* ExprIterator::operator*() const { return cast<Expr>(*I); } 1841Expr* ExprIterator::operator->() const { return cast<Expr>(*I); } 1842const Expr* ConstExprIterator::operator[](size_t idx) const { 1843 return cast<Expr>(I[idx]); 1844} 1845const Expr* ConstExprIterator::operator*() const { return cast<Expr>(*I); } 1846const Expr* ConstExprIterator::operator->() const { return cast<Expr>(*I); } 1847 1848//===----------------------------------------------------------------------===// 1849// Child Iterators for iterating over subexpressions/substatements 1850//===----------------------------------------------------------------------===// 1851 1852// DeclRefExpr 1853Stmt::child_iterator DeclRefExpr::child_begin() { return child_iterator(); } 1854Stmt::child_iterator DeclRefExpr::child_end() { return child_iterator(); } 1855 1856// ObjCIvarRefExpr 1857Stmt::child_iterator ObjCIvarRefExpr::child_begin() { return &Base; } 1858Stmt::child_iterator ObjCIvarRefExpr::child_end() { return &Base+1; } 1859 1860// ObjCPropertyRefExpr 1861Stmt::child_iterator ObjCPropertyRefExpr::child_begin() { return &Base; } 1862Stmt::child_iterator ObjCPropertyRefExpr::child_end() { return &Base+1; } 1863 1864// ObjCKVCRefExpr 1865Stmt::child_iterator ObjCKVCRefExpr::child_begin() { return &Base; } 1866Stmt::child_iterator ObjCKVCRefExpr::child_end() { return &Base+1; } 1867 1868// ObjCSuperExpr 1869Stmt::child_iterator ObjCSuperExpr::child_begin() { return child_iterator(); } 1870Stmt::child_iterator ObjCSuperExpr::child_end() { return child_iterator(); } 1871 1872// ObjCIsaExpr 1873Stmt::child_iterator ObjCIsaExpr::child_begin() { return &Base; } 1874Stmt::child_iterator ObjCIsaExpr::child_end() { return &Base+1; } 1875 1876// PredefinedExpr 1877Stmt::child_iterator PredefinedExpr::child_begin() { return child_iterator(); } 1878Stmt::child_iterator PredefinedExpr::child_end() { return child_iterator(); } 1879 1880// IntegerLiteral 1881Stmt::child_iterator IntegerLiteral::child_begin() { return child_iterator(); } 1882Stmt::child_iterator IntegerLiteral::child_end() { return child_iterator(); } 1883 1884// CharacterLiteral 1885Stmt::child_iterator CharacterLiteral::child_begin() { return child_iterator();} 1886Stmt::child_iterator CharacterLiteral::child_end() { return child_iterator(); } 1887 1888// FloatingLiteral 1889Stmt::child_iterator FloatingLiteral::child_begin() { return child_iterator(); } 1890Stmt::child_iterator FloatingLiteral::child_end() { return child_iterator(); } 1891 1892// ImaginaryLiteral 1893Stmt::child_iterator ImaginaryLiteral::child_begin() { return &Val; } 1894Stmt::child_iterator ImaginaryLiteral::child_end() { return &Val+1; } 1895 1896// StringLiteral 1897Stmt::child_iterator StringLiteral::child_begin() { return child_iterator(); } 1898Stmt::child_iterator StringLiteral::child_end() { return child_iterator(); } 1899 1900// ParenExpr 1901Stmt::child_iterator ParenExpr::child_begin() { return &Val; } 1902Stmt::child_iterator ParenExpr::child_end() { return &Val+1; } 1903 1904// UnaryOperator 1905Stmt::child_iterator UnaryOperator::child_begin() { return &Val; } 1906Stmt::child_iterator UnaryOperator::child_end() { return &Val+1; } 1907 1908// SizeOfAlignOfExpr 1909Stmt::child_iterator SizeOfAlignOfExpr::child_begin() { 1910 // If this is of a type and the type is a VLA type (and not a typedef), the 1911 // size expression of the VLA needs to be treated as an executable expression. 1912 // Why isn't this weirdness documented better in StmtIterator? 1913 if (isArgumentType()) { 1914 if (VariableArrayType* T = dyn_cast<VariableArrayType>( 1915 getArgumentType().getTypePtr())) 1916 return child_iterator(T); 1917 return child_iterator(); 1918 } 1919 return child_iterator(&Argument.Ex); 1920} 1921Stmt::child_iterator SizeOfAlignOfExpr::child_end() { 1922 if (isArgumentType()) 1923 return child_iterator(); 1924 return child_iterator(&Argument.Ex + 1); 1925} 1926 1927// ArraySubscriptExpr 1928Stmt::child_iterator ArraySubscriptExpr::child_begin() { 1929 return &SubExprs[0]; 1930} 1931Stmt::child_iterator ArraySubscriptExpr::child_end() { 1932 return &SubExprs[0]+END_EXPR; 1933} 1934 1935// CallExpr 1936Stmt::child_iterator CallExpr::child_begin() { 1937 return &SubExprs[0]; 1938} 1939Stmt::child_iterator CallExpr::child_end() { 1940 return &SubExprs[0]+NumArgs+ARGS_START; 1941} 1942 1943// MemberExpr 1944Stmt::child_iterator MemberExpr::child_begin() { return &Base; } 1945Stmt::child_iterator MemberExpr::child_end() { return &Base+1; } 1946 1947// ExtVectorElementExpr 1948Stmt::child_iterator ExtVectorElementExpr::child_begin() { return &Base; } 1949Stmt::child_iterator ExtVectorElementExpr::child_end() { return &Base+1; } 1950 1951// CompoundLiteralExpr 1952Stmt::child_iterator CompoundLiteralExpr::child_begin() { return &Init; } 1953Stmt::child_iterator CompoundLiteralExpr::child_end() { return &Init+1; } 1954 1955// CastExpr 1956Stmt::child_iterator CastExpr::child_begin() { return &Op; } 1957Stmt::child_iterator CastExpr::child_end() { return &Op+1; } 1958 1959// BinaryOperator 1960Stmt::child_iterator BinaryOperator::child_begin() { 1961 return &SubExprs[0]; 1962} 1963Stmt::child_iterator BinaryOperator::child_end() { 1964 return &SubExprs[0]+END_EXPR; 1965} 1966 1967// ConditionalOperator 1968Stmt::child_iterator ConditionalOperator::child_begin() { 1969 return &SubExprs[0]; 1970} 1971Stmt::child_iterator ConditionalOperator::child_end() { 1972 return &SubExprs[0]+END_EXPR; 1973} 1974 1975// AddrLabelExpr 1976Stmt::child_iterator AddrLabelExpr::child_begin() { return child_iterator(); } 1977Stmt::child_iterator AddrLabelExpr::child_end() { return child_iterator(); } 1978 1979// StmtExpr 1980Stmt::child_iterator StmtExpr::child_begin() { return &SubStmt; } 1981Stmt::child_iterator StmtExpr::child_end() { return &SubStmt+1; } 1982 1983// TypesCompatibleExpr 1984Stmt::child_iterator TypesCompatibleExpr::child_begin() { 1985 return child_iterator(); 1986} 1987 1988Stmt::child_iterator TypesCompatibleExpr::child_end() { 1989 return child_iterator(); 1990} 1991 1992// ChooseExpr 1993Stmt::child_iterator ChooseExpr::child_begin() { return &SubExprs[0]; } 1994Stmt::child_iterator ChooseExpr::child_end() { return &SubExprs[0]+END_EXPR; } 1995 1996// GNUNullExpr 1997Stmt::child_iterator GNUNullExpr::child_begin() { return child_iterator(); } 1998Stmt::child_iterator GNUNullExpr::child_end() { return child_iterator(); } 1999 2000// ShuffleVectorExpr 2001Stmt::child_iterator ShuffleVectorExpr::child_begin() { 2002 return &SubExprs[0]; 2003} 2004Stmt::child_iterator ShuffleVectorExpr::child_end() { 2005 return &SubExprs[0]+NumExprs; 2006} 2007 2008// VAArgExpr 2009Stmt::child_iterator VAArgExpr::child_begin() { return &Val; } 2010Stmt::child_iterator VAArgExpr::child_end() { return &Val+1; } 2011 2012// InitListExpr 2013Stmt::child_iterator InitListExpr::child_begin() { 2014 return InitExprs.size() ? &InitExprs[0] : 0; 2015} 2016Stmt::child_iterator InitListExpr::child_end() { 2017 return InitExprs.size() ? &InitExprs[0] + InitExprs.size() : 0; 2018} 2019 2020// DesignatedInitExpr 2021Stmt::child_iterator DesignatedInitExpr::child_begin() { 2022 char* Ptr = static_cast<char*>(static_cast<void *>(this)); 2023 Ptr += sizeof(DesignatedInitExpr); 2024 return reinterpret_cast<Stmt**>(reinterpret_cast<void**>(Ptr)); 2025} 2026Stmt::child_iterator DesignatedInitExpr::child_end() { 2027 return child_iterator(&*child_begin() + NumSubExprs); 2028} 2029 2030// ImplicitValueInitExpr 2031Stmt::child_iterator ImplicitValueInitExpr::child_begin() { 2032 return child_iterator(); 2033} 2034 2035Stmt::child_iterator ImplicitValueInitExpr::child_end() { 2036 return child_iterator(); 2037} 2038 2039// ParenListExpr 2040Stmt::child_iterator ParenListExpr::child_begin() { 2041 return &Exprs[0]; 2042} 2043Stmt::child_iterator ParenListExpr::child_end() { 2044 return &Exprs[0]+NumExprs; 2045} 2046 2047// ObjCStringLiteral 2048Stmt::child_iterator ObjCStringLiteral::child_begin() { 2049 return &String; 2050} 2051Stmt::child_iterator ObjCStringLiteral::child_end() { 2052 return &String+1; 2053} 2054 2055// ObjCEncodeExpr 2056Stmt::child_iterator ObjCEncodeExpr::child_begin() { return child_iterator(); } 2057Stmt::child_iterator ObjCEncodeExpr::child_end() { return child_iterator(); } 2058 2059// ObjCSelectorExpr 2060Stmt::child_iterator ObjCSelectorExpr::child_begin() { 2061 return child_iterator(); 2062} 2063Stmt::child_iterator ObjCSelectorExpr::child_end() { 2064 return child_iterator(); 2065} 2066 2067// ObjCProtocolExpr 2068Stmt::child_iterator ObjCProtocolExpr::child_begin() { 2069 return child_iterator(); 2070} 2071Stmt::child_iterator ObjCProtocolExpr::child_end() { 2072 return child_iterator(); 2073} 2074 2075// ObjCMessageExpr 2076Stmt::child_iterator ObjCMessageExpr::child_begin() { 2077 return getReceiver() ? &SubExprs[0] : &SubExprs[0] + ARGS_START; 2078} 2079Stmt::child_iterator ObjCMessageExpr::child_end() { 2080 return &SubExprs[0]+ARGS_START+getNumArgs(); 2081} 2082 2083// Blocks 2084Stmt::child_iterator BlockExpr::child_begin() { return child_iterator(); } 2085Stmt::child_iterator BlockExpr::child_end() { return child_iterator(); } 2086 2087Stmt::child_iterator BlockDeclRefExpr::child_begin() { return child_iterator();} 2088Stmt::child_iterator BlockDeclRefExpr::child_end() { return child_iterator(); } 2089