SemaExpr.cpp revision 46d9134b995120acf99269d812da7c79d195ef3e
1//===--- SemaExpr.cpp - Semantic Analysis for Expressions -----------------===// 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 semantic analysis for expressions. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "clang/AST/ASTContext.h" 16#include "clang/AST/DeclObjC.h" 17#include "clang/AST/ExprCXX.h" 18#include "clang/AST/ExprObjC.h" 19#include "clang/Lex/Preprocessor.h" 20#include "clang/Lex/LiteralSupport.h" 21#include "clang/Basic/Diagnostic.h" 22#include "clang/Basic/SourceManager.h" 23#include "clang/Basic/TargetInfo.h" 24#include "clang/Parse/DeclSpec.h" 25#include "clang/Parse/Scope.h" 26using namespace clang; 27 28//===----------------------------------------------------------------------===// 29// Standard Promotions and Conversions 30//===----------------------------------------------------------------------===// 31 32/// DefaultFunctionArrayConversion (C99 6.3.2.1p3, C99 6.3.2.1p4). 33void Sema::DefaultFunctionArrayConversion(Expr *&E) { 34 QualType Ty = E->getType(); 35 assert(!Ty.isNull() && "DefaultFunctionArrayConversion - missing type"); 36 37 if (const ReferenceType *ref = Ty->getAsReferenceType()) { 38 ImpCastExprToType(E, ref->getPointeeType()); // C++ [expr] 39 Ty = E->getType(); 40 } 41 if (Ty->isFunctionType()) 42 ImpCastExprToType(E, Context.getPointerType(Ty)); 43 else if (Ty->isArrayType()) { 44 // In C90 mode, arrays only promote to pointers if the array expression is 45 // an lvalue. The relevant legalese is C90 6.2.2.1p3: "an lvalue that has 46 // type 'array of type' is converted to an expression that has type 'pointer 47 // to type'...". In C99 this was changed to: C99 6.3.2.1p3: "an expression 48 // that has type 'array of type' ...". The relevant change is "an lvalue" 49 // (C90) to "an expression" (C99). 50 // 51 // C++ 4.2p1: 52 // An lvalue or rvalue of type "array of N T" or "array of unknown bound of 53 // T" can be converted to an rvalue of type "pointer to T". 54 // 55 if (getLangOptions().C99 || getLangOptions().CPlusPlus || 56 E->isLvalue(Context) == Expr::LV_Valid) 57 ImpCastExprToType(E, Context.getArrayDecayedType(Ty)); 58 } 59} 60 61/// UsualUnaryConversions - Performs various conversions that are common to most 62/// operators (C99 6.3). The conversions of array and function types are 63/// sometimes surpressed. For example, the array->pointer conversion doesn't 64/// apply if the array is an argument to the sizeof or address (&) operators. 65/// In these instances, this routine should *not* be called. 66Expr *Sema::UsualUnaryConversions(Expr *&Expr) { 67 QualType Ty = Expr->getType(); 68 assert(!Ty.isNull() && "UsualUnaryConversions - missing type"); 69 70 if (const ReferenceType *Ref = Ty->getAsReferenceType()) { 71 ImpCastExprToType(Expr, Ref->getPointeeType()); // C++ [expr] 72 Ty = Expr->getType(); 73 } 74 if (Ty->isPromotableIntegerType()) // C99 6.3.1.1p2 75 ImpCastExprToType(Expr, Context.IntTy); 76 else 77 DefaultFunctionArrayConversion(Expr); 78 79 return Expr; 80} 81 82/// DefaultArgumentPromotion (C99 6.5.2.2p6). Used for function calls that 83/// do not have a prototype. Arguments that have type float are promoted to 84/// double. All other argument types are converted by UsualUnaryConversions(). 85void Sema::DefaultArgumentPromotion(Expr *&Expr) { 86 QualType Ty = Expr->getType(); 87 assert(!Ty.isNull() && "DefaultArgumentPromotion - missing type"); 88 89 // If this is a 'float' (CVR qualified or typedef) promote to double. 90 if (const BuiltinType *BT = Ty->getAsBuiltinType()) 91 if (BT->getKind() == BuiltinType::Float) 92 return ImpCastExprToType(Expr, Context.DoubleTy); 93 94 UsualUnaryConversions(Expr); 95} 96 97/// UsualArithmeticConversions - Performs various conversions that are common to 98/// binary operators (C99 6.3.1.8). If both operands aren't arithmetic, this 99/// routine returns the first non-arithmetic type found. The client is 100/// responsible for emitting appropriate error diagnostics. 101/// FIXME: verify the conversion rules for "complex int" are consistent with 102/// GCC. 103QualType Sema::UsualArithmeticConversions(Expr *&lhsExpr, Expr *&rhsExpr, 104 bool isCompAssign) { 105 if (!isCompAssign) { 106 UsualUnaryConversions(lhsExpr); 107 UsualUnaryConversions(rhsExpr); 108 } 109 // For conversion purposes, we ignore any qualifiers. 110 // For example, "const float" and "float" are equivalent. 111 QualType lhs = 112 Context.getCanonicalType(lhsExpr->getType()).getUnqualifiedType(); 113 QualType rhs = 114 Context.getCanonicalType(rhsExpr->getType()).getUnqualifiedType(); 115 116 // If both types are identical, no conversion is needed. 117 if (lhs == rhs) 118 return lhs; 119 120 // If either side is a non-arithmetic type (e.g. a pointer), we are done. 121 // The caller can deal with this (e.g. pointer + int). 122 if (!lhs->isArithmeticType() || !rhs->isArithmeticType()) 123 return lhs; 124 125 // At this point, we have two different arithmetic types. 126 127 // Handle complex types first (C99 6.3.1.8p1). 128 if (lhs->isComplexType() || rhs->isComplexType()) { 129 // if we have an integer operand, the result is the complex type. 130 if (rhs->isIntegerType() || rhs->isComplexIntegerType()) { 131 // convert the rhs to the lhs complex type. 132 if (!isCompAssign) ImpCastExprToType(rhsExpr, lhs); 133 return lhs; 134 } 135 if (lhs->isIntegerType() || lhs->isComplexIntegerType()) { 136 // convert the lhs to the rhs complex type. 137 if (!isCompAssign) ImpCastExprToType(lhsExpr, rhs); 138 return rhs; 139 } 140 // This handles complex/complex, complex/float, or float/complex. 141 // When both operands are complex, the shorter operand is converted to the 142 // type of the longer, and that is the type of the result. This corresponds 143 // to what is done when combining two real floating-point operands. 144 // The fun begins when size promotion occur across type domains. 145 // From H&S 6.3.4: When one operand is complex and the other is a real 146 // floating-point type, the less precise type is converted, within it's 147 // real or complex domain, to the precision of the other type. For example, 148 // when combining a "long double" with a "double _Complex", the 149 // "double _Complex" is promoted to "long double _Complex". 150 int result = Context.getFloatingTypeOrder(lhs, rhs); 151 152 if (result > 0) { // The left side is bigger, convert rhs. 153 rhs = Context.getFloatingTypeOfSizeWithinDomain(lhs, rhs); 154 if (!isCompAssign) 155 ImpCastExprToType(rhsExpr, rhs); 156 } else if (result < 0) { // The right side is bigger, convert lhs. 157 lhs = Context.getFloatingTypeOfSizeWithinDomain(rhs, lhs); 158 if (!isCompAssign) 159 ImpCastExprToType(lhsExpr, lhs); 160 } 161 // At this point, lhs and rhs have the same rank/size. Now, make sure the 162 // domains match. This is a requirement for our implementation, C99 163 // does not require this promotion. 164 if (lhs != rhs) { // Domains don't match, we have complex/float mix. 165 if (lhs->isRealFloatingType()) { // handle "double, _Complex double". 166 if (!isCompAssign) 167 ImpCastExprToType(lhsExpr, rhs); 168 return rhs; 169 } else { // handle "_Complex double, double". 170 if (!isCompAssign) 171 ImpCastExprToType(rhsExpr, lhs); 172 return lhs; 173 } 174 } 175 return lhs; // The domain/size match exactly. 176 } 177 // Now handle "real" floating types (i.e. float, double, long double). 178 if (lhs->isRealFloatingType() || rhs->isRealFloatingType()) { 179 // if we have an integer operand, the result is the real floating type. 180 if (rhs->isIntegerType() || rhs->isComplexIntegerType()) { 181 // convert rhs to the lhs floating point type. 182 if (!isCompAssign) ImpCastExprToType(rhsExpr, lhs); 183 return lhs; 184 } 185 if (lhs->isIntegerType() || lhs->isComplexIntegerType()) { 186 // convert lhs to the rhs floating point type. 187 if (!isCompAssign) ImpCastExprToType(lhsExpr, rhs); 188 return rhs; 189 } 190 // We have two real floating types, float/complex combos were handled above. 191 // Convert the smaller operand to the bigger result. 192 int result = Context.getFloatingTypeOrder(lhs, rhs); 193 194 if (result > 0) { // convert the rhs 195 if (!isCompAssign) ImpCastExprToType(rhsExpr, lhs); 196 return lhs; 197 } 198 if (result < 0) { // convert the lhs 199 if (!isCompAssign) ImpCastExprToType(lhsExpr, rhs); // convert the lhs 200 return rhs; 201 } 202 assert(0 && "Sema::UsualArithmeticConversions(): illegal float comparison"); 203 } 204 if (lhs->isComplexIntegerType() || rhs->isComplexIntegerType()) { 205 // Handle GCC complex int extension. 206 const ComplexType *lhsComplexInt = lhs->getAsComplexIntegerType(); 207 const ComplexType *rhsComplexInt = rhs->getAsComplexIntegerType(); 208 209 if (lhsComplexInt && rhsComplexInt) { 210 if (Context.getIntegerTypeOrder(lhsComplexInt->getElementType(), 211 rhsComplexInt->getElementType()) >= 0) { 212 // convert the rhs 213 if (!isCompAssign) ImpCastExprToType(rhsExpr, lhs); 214 return lhs; 215 } 216 if (!isCompAssign) 217 ImpCastExprToType(lhsExpr, rhs); // convert the lhs 218 return rhs; 219 } else if (lhsComplexInt && rhs->isIntegerType()) { 220 // convert the rhs to the lhs complex type. 221 if (!isCompAssign) ImpCastExprToType(rhsExpr, lhs); 222 return lhs; 223 } else if (rhsComplexInt && lhs->isIntegerType()) { 224 // convert the lhs to the rhs complex type. 225 if (!isCompAssign) ImpCastExprToType(lhsExpr, rhs); 226 return rhs; 227 } 228 } 229 // Finally, we have two differing integer types. 230 // The rules for this case are in C99 6.3.1.8 231 int compare = Context.getIntegerTypeOrder(lhs, rhs); 232 bool lhsSigned = lhs->isSignedIntegerType(), 233 rhsSigned = rhs->isSignedIntegerType(); 234 QualType destType; 235 if (lhsSigned == rhsSigned) { 236 // Same signedness; use the higher-ranked type 237 destType = compare >= 0 ? lhs : rhs; 238 } else if (compare != (lhsSigned ? 1 : -1)) { 239 // The unsigned type has greater than or equal rank to the 240 // signed type, so use the unsigned type 241 destType = lhsSigned ? rhs : lhs; 242 } else if (Context.getIntWidth(lhs) != Context.getIntWidth(rhs)) { 243 // The two types are different widths; if we are here, that 244 // means the signed type is larger than the unsigned type, so 245 // use the signed type. 246 destType = lhsSigned ? lhs : rhs; 247 } else { 248 // The signed type is higher-ranked than the unsigned type, 249 // but isn't actually any bigger (like unsigned int and long 250 // on most 32-bit systems). Use the unsigned type corresponding 251 // to the signed type. 252 destType = Context.getCorrespondingUnsignedType(lhsSigned ? lhs : rhs); 253 } 254 if (!isCompAssign) { 255 ImpCastExprToType(lhsExpr, destType); 256 ImpCastExprToType(rhsExpr, destType); 257 } 258 return destType; 259} 260 261//===----------------------------------------------------------------------===// 262// Semantic Analysis for various Expression Types 263//===----------------------------------------------------------------------===// 264 265 266/// ActOnStringLiteral - The specified tokens were lexed as pasted string 267/// fragments (e.g. "foo" "bar" L"baz"). The result string has to handle string 268/// concatenation ([C99 5.1.1.2, translation phase #6]), so it may come from 269/// multiple tokens. However, the common case is that StringToks points to one 270/// string. 271/// 272Action::ExprResult 273Sema::ActOnStringLiteral(const Token *StringToks, unsigned NumStringToks) { 274 assert(NumStringToks && "Must have at least one string!"); 275 276 StringLiteralParser Literal(StringToks, NumStringToks, PP, Context.Target); 277 if (Literal.hadError) 278 return ExprResult(true); 279 280 llvm::SmallVector<SourceLocation, 4> StringTokLocs; 281 for (unsigned i = 0; i != NumStringToks; ++i) 282 StringTokLocs.push_back(StringToks[i].getLocation()); 283 284 // Verify that pascal strings aren't too large. 285 if (Literal.Pascal && Literal.GetStringLength() > 256) 286 return Diag(StringToks[0].getLocation(), diag::err_pascal_string_too_long, 287 SourceRange(StringToks[0].getLocation(), 288 StringToks[NumStringToks-1].getLocation())); 289 290 QualType StrTy = Context.CharTy; 291 if (Literal.AnyWide) StrTy = Context.getWCharType(); 292 if (Literal.Pascal) StrTy = Context.UnsignedCharTy; 293 294 // A C++ string literal has a const-qualified element type (C++ 2.13.4p1). 295 if (getLangOptions().CPlusPlus) 296 StrTy.addConst(); 297 298 // Get an array type for the string, according to C99 6.4.5. This includes 299 // the nul terminator character as well as the string length for pascal 300 // strings. 301 StrTy = Context.getConstantArrayType(StrTy, 302 llvm::APInt(32, Literal.GetStringLength()+1), 303 ArrayType::Normal, 0); 304 305 // Pass &StringTokLocs[0], StringTokLocs.size() to factory! 306 return new StringLiteral(Literal.GetString(), Literal.GetStringLength(), 307 Literal.AnyWide, StrTy, 308 StringToks[0].getLocation(), 309 StringToks[NumStringToks-1].getLocation()); 310} 311 312/// DeclDefinedWithinScope - Return true if the specified decl is defined at or 313/// within the 'Within' scope. The current Scope is CurScope. 314/// 315/// FIXME: This method is extremely inefficient (linear scan), this should not 316/// be used in common cases. Replace with the more modern DeclContext. We need 317/// to make sure both assignments below produce an error. 318/// 319/// int main(int argc) { 320/// int xx; 321/// ^(int X) { 322/// xx = 4; // error (variable is not assignable) 323/// argc = 3; // no error. 324/// }; 325/// } 326/// 327static bool DeclDefinedWithinScope(ScopedDecl *D, Scope *Within, 328 Scope *CurScope) { 329 while (1) { 330 assert(CurScope && "CurScope not nested within 'Within'?"); 331 332 // Check this scope for the decl. 333 if (CurScope->isDeclScope(D)) return true; 334 335 if (CurScope == Within) return false; 336 CurScope = CurScope->getParent(); 337 } 338} 339 340/// ActOnIdentifierExpr - The parser read an identifier in expression context, 341/// validate it per-C99 6.5.1. HasTrailingLParen indicates whether this 342/// identifier is used in a function call context. 343Sema::ExprResult Sema::ActOnIdentifierExpr(Scope *S, SourceLocation Loc, 344 IdentifierInfo &II, 345 bool HasTrailingLParen) { 346 // Could be enum-constant, value decl, instance variable, etc. 347 Decl *D = LookupDecl(&II, Decl::IDNS_Ordinary, S); 348 349 // If this reference is in an Objective-C method, then ivar lookup happens as 350 // well. 351 if (getCurMethodDecl()) { 352 ScopedDecl *SD = dyn_cast_or_null<ScopedDecl>(D); 353 // There are two cases to handle here. 1) scoped lookup could have failed, 354 // in which case we should look for an ivar. 2) scoped lookup could have 355 // found a decl, but that decl is outside the current method (i.e. a global 356 // variable). In these two cases, we do a lookup for an ivar with this 357 // name, if the lookup suceeds, we replace it our current decl. 358 if (SD == 0 || SD->isDefinedOutsideFunctionOrMethod()) { 359 ObjCInterfaceDecl *IFace = getCurMethodDecl()->getClassInterface(); 360 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(&II)) { 361 // FIXME: This should use a new expr for a direct reference, don't turn 362 // this into Self->ivar, just return a BareIVarExpr or something. 363 IdentifierInfo &II = Context.Idents.get("self"); 364 ExprResult SelfExpr = ActOnIdentifierExpr(S, Loc, II, false); 365 return new ObjCIvarRefExpr(IV, IV->getType(), Loc, 366 static_cast<Expr*>(SelfExpr.Val), true, true); 367 } 368 } 369 // Needed to implement property "super.method" notation. 370 if (SD == 0 && &II == SuperID) { 371 QualType T = Context.getPointerType(Context.getObjCInterfaceType( 372 getCurMethodDecl()->getClassInterface())); 373 return new PredefinedExpr(Loc, T, PredefinedExpr::ObjCSuper); 374 } 375 } 376 // If we are parsing a block, check the block parameter list. 377 if (CurBlock) { 378 BlockSemaInfo *BLK = CurBlock; 379 do { 380 for (unsigned i = 0, e = BLK->Params.size(); i != e && D == 0; ++i) 381 if (BLK->Params[i]->getIdentifier() == &II) 382 D = BLK->Params[i]; 383 if (D) 384 break; // Found! 385 } while ((BLK = BLK->PrevBlockInfo)); // Look through any enclosing blocks. 386 } 387 if (D == 0) { 388 // Otherwise, this could be an implicitly declared function reference (legal 389 // in C90, extension in C99). 390 if (HasTrailingLParen && 391 !getLangOptions().CPlusPlus) // Not in C++. 392 D = ImplicitlyDefineFunction(Loc, II, S); 393 else { 394 // If this name wasn't predeclared and if this is not a function call, 395 // diagnose the problem. 396 return Diag(Loc, diag::err_undeclared_var_use, II.getName()); 397 } 398 } 399 400 if (CXXFieldDecl *FD = dyn_cast<CXXFieldDecl>(D)) { 401 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(CurContext)) { 402 if (MD->isStatic()) 403 // "invalid use of member 'x' in static member function" 404 return Diag(Loc, diag::err_invalid_member_use_in_static_method, 405 FD->getName()); 406 if (cast<CXXRecordDecl>(MD->getParent()) != FD->getParent()) 407 // "invalid use of nonstatic data member 'x'" 408 return Diag(Loc, diag::err_invalid_non_static_member_use, 409 FD->getName()); 410 411 if (FD->isInvalidDecl()) 412 return true; 413 414 // FIXME: Use DeclRefExpr or a new Expr for a direct CXXField reference. 415 ExprResult ThisExpr = ActOnCXXThis(SourceLocation()); 416 return new MemberExpr(static_cast<Expr*>(ThisExpr.Val), 417 true, FD, Loc, FD->getType()); 418 } 419 420 return Diag(Loc, diag::err_invalid_non_static_member_use, FD->getName()); 421 } 422 if (isa<TypedefDecl>(D)) 423 return Diag(Loc, diag::err_unexpected_typedef, II.getName()); 424 if (isa<ObjCInterfaceDecl>(D)) 425 return Diag(Loc, diag::err_unexpected_interface, II.getName()); 426 if (isa<NamespaceDecl>(D)) 427 return Diag(Loc, diag::err_unexpected_namespace, II.getName()); 428 429 // Make the DeclRefExpr or BlockDeclRefExpr for the decl. 430 ValueDecl *VD = cast<ValueDecl>(D); 431 432 // check if referencing an identifier with __attribute__((deprecated)). 433 if (VD->getAttr<DeprecatedAttr>()) 434 Diag(Loc, diag::warn_deprecated, VD->getName()); 435 436 // Only create DeclRefExpr's for valid Decl's. 437 if (VD->isInvalidDecl()) 438 return true; 439 440 // If this reference is not in a block or if the referenced variable is 441 // within the block, create a normal DeclRefExpr. 442 // 443 // FIXME: This will create BlockDeclRefExprs for global variables, 444 // function references, etc which is suboptimal :) and breaks 445 // things like "integer constant expression" tests. 446 // 447 if (!CurBlock || DeclDefinedWithinScope(VD, CurBlock->TheScope, S) || 448 isa<EnumConstantDecl>(VD) || isa<ParmVarDecl>(VD)) 449 return new DeclRefExpr(VD, VD->getType(), Loc); 450 451 // If we are in a block and the variable is outside the current block, 452 // bind the variable reference with a BlockDeclRefExpr. 453 454 // The BlocksAttr indicates the variable is bound by-reference. 455 if (VD->getAttr<BlocksAttr>()) 456 return new BlockDeclRefExpr(VD, VD->getType(), Loc, true); 457 458 // Variable will be bound by-copy, make it const within the closure. 459 VD->getType().addConst(); 460 return new BlockDeclRefExpr(VD, VD->getType(), Loc, false); 461} 462 463Sema::ExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, 464 tok::TokenKind Kind) { 465 PredefinedExpr::IdentType IT; 466 467 switch (Kind) { 468 default: assert(0 && "Unknown simple primary expr!"); 469 case tok::kw___func__: IT = PredefinedExpr::Func; break; // [C99 6.4.2.2] 470 case tok::kw___FUNCTION__: IT = PredefinedExpr::Function; break; 471 case tok::kw___PRETTY_FUNCTION__: IT = PredefinedExpr::PrettyFunction; break; 472 } 473 474 // Verify that this is in a function context. 475 if (getCurFunctionDecl() == 0 && getCurMethodDecl() == 0) 476 return Diag(Loc, diag::err_predef_outside_function); 477 478 // Pre-defined identifiers are of type char[x], where x is the length of the 479 // string. 480 unsigned Length; 481 if (getCurFunctionDecl()) 482 Length = getCurFunctionDecl()->getIdentifier()->getLength(); 483 else 484 Length = getCurMethodDecl()->getSynthesizedMethodSize(); 485 486 llvm::APInt LengthI(32, Length + 1); 487 QualType ResTy = Context.CharTy.getQualifiedType(QualType::Const); 488 ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal, 0); 489 return new PredefinedExpr(Loc, ResTy, IT); 490} 491 492Sema::ExprResult Sema::ActOnCharacterConstant(const Token &Tok) { 493 llvm::SmallString<16> CharBuffer; 494 CharBuffer.resize(Tok.getLength()); 495 const char *ThisTokBegin = &CharBuffer[0]; 496 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin); 497 498 CharLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 499 Tok.getLocation(), PP); 500 if (Literal.hadError()) 501 return ExprResult(true); 502 503 QualType type = getLangOptions().CPlusPlus ? Context.CharTy : Context.IntTy; 504 505 return new CharacterLiteral(Literal.getValue(), Literal.isWide(), type, 506 Tok.getLocation()); 507} 508 509Action::ExprResult Sema::ActOnNumericConstant(const Token &Tok) { 510 // fast path for a single digit (which is quite common). A single digit 511 // cannot have a trigraph, escaped newline, radix prefix, or type suffix. 512 if (Tok.getLength() == 1) { 513 const char *Ty = PP.getSourceManager().getCharacterData(Tok.getLocation()); 514 515 unsigned IntSize =static_cast<unsigned>(Context.getTypeSize(Context.IntTy)); 516 return ExprResult(new IntegerLiteral(llvm::APInt(IntSize, *Ty-'0'), 517 Context.IntTy, 518 Tok.getLocation())); 519 } 520 llvm::SmallString<512> IntegerBuffer; 521 // Add padding so that NumericLiteralParser can overread by one character. 522 IntegerBuffer.resize(Tok.getLength()+1); 523 const char *ThisTokBegin = &IntegerBuffer[0]; 524 525 // Get the spelling of the token, which eliminates trigraphs, etc. 526 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin); 527 528 NumericLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 529 Tok.getLocation(), PP); 530 if (Literal.hadError) 531 return ExprResult(true); 532 533 Expr *Res; 534 535 if (Literal.isFloatingLiteral()) { 536 QualType Ty; 537 if (Literal.isFloat) 538 Ty = Context.FloatTy; 539 else if (!Literal.isLong) 540 Ty = Context.DoubleTy; 541 else 542 Ty = Context.LongDoubleTy; 543 544 const llvm::fltSemantics &Format = Context.getFloatTypeSemantics(Ty); 545 546 // isExact will be set by GetFloatValue(). 547 bool isExact = false; 548 Res = new FloatingLiteral(Literal.GetFloatValue(Format, &isExact), &isExact, 549 Ty, Tok.getLocation()); 550 551 } else if (!Literal.isIntegerLiteral()) { 552 return ExprResult(true); 553 } else { 554 QualType Ty; 555 556 // long long is a C99 feature. 557 if (!getLangOptions().C99 && !getLangOptions().CPlusPlus0x && 558 Literal.isLongLong) 559 Diag(Tok.getLocation(), diag::ext_longlong); 560 561 // Get the value in the widest-possible width. 562 llvm::APInt ResultVal(Context.Target.getIntMaxTWidth(), 0); 563 564 if (Literal.GetIntegerValue(ResultVal)) { 565 // If this value didn't fit into uintmax_t, warn and force to ull. 566 Diag(Tok.getLocation(), diag::warn_integer_too_large); 567 Ty = Context.UnsignedLongLongTy; 568 assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() && 569 "long long is not intmax_t?"); 570 } else { 571 // If this value fits into a ULL, try to figure out what else it fits into 572 // according to the rules of C99 6.4.4.1p5. 573 574 // Octal, Hexadecimal, and integers with a U suffix are allowed to 575 // be an unsigned int. 576 bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10; 577 578 // Check from smallest to largest, picking the smallest type we can. 579 unsigned Width = 0; 580 if (!Literal.isLong && !Literal.isLongLong) { 581 // Are int/unsigned possibilities? 582 unsigned IntSize = Context.Target.getIntWidth(); 583 584 // Does it fit in a unsigned int? 585 if (ResultVal.isIntN(IntSize)) { 586 // Does it fit in a signed int? 587 if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0) 588 Ty = Context.IntTy; 589 else if (AllowUnsigned) 590 Ty = Context.UnsignedIntTy; 591 Width = IntSize; 592 } 593 } 594 595 // Are long/unsigned long possibilities? 596 if (Ty.isNull() && !Literal.isLongLong) { 597 unsigned LongSize = Context.Target.getLongWidth(); 598 599 // Does it fit in a unsigned long? 600 if (ResultVal.isIntN(LongSize)) { 601 // Does it fit in a signed long? 602 if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0) 603 Ty = Context.LongTy; 604 else if (AllowUnsigned) 605 Ty = Context.UnsignedLongTy; 606 Width = LongSize; 607 } 608 } 609 610 // Finally, check long long if needed. 611 if (Ty.isNull()) { 612 unsigned LongLongSize = Context.Target.getLongLongWidth(); 613 614 // Does it fit in a unsigned long long? 615 if (ResultVal.isIntN(LongLongSize)) { 616 // Does it fit in a signed long long? 617 if (!Literal.isUnsigned && ResultVal[LongLongSize-1] == 0) 618 Ty = Context.LongLongTy; 619 else if (AllowUnsigned) 620 Ty = Context.UnsignedLongLongTy; 621 Width = LongLongSize; 622 } 623 } 624 625 // If we still couldn't decide a type, we probably have something that 626 // does not fit in a signed long long, but has no U suffix. 627 if (Ty.isNull()) { 628 Diag(Tok.getLocation(), diag::warn_integer_too_large_for_signed); 629 Ty = Context.UnsignedLongLongTy; 630 Width = Context.Target.getLongLongWidth(); 631 } 632 633 if (ResultVal.getBitWidth() != Width) 634 ResultVal.trunc(Width); 635 } 636 637 Res = new IntegerLiteral(ResultVal, Ty, Tok.getLocation()); 638 } 639 640 // If this is an imaginary literal, create the ImaginaryLiteral wrapper. 641 if (Literal.isImaginary) 642 Res = new ImaginaryLiteral(Res, Context.getComplexType(Res->getType())); 643 644 return Res; 645} 646 647Action::ExprResult Sema::ActOnParenExpr(SourceLocation L, SourceLocation R, 648 ExprTy *Val) { 649 Expr *E = (Expr *)Val; 650 assert((E != 0) && "ActOnParenExpr() missing expr"); 651 return new ParenExpr(L, R, E); 652} 653 654/// The UsualUnaryConversions() function is *not* called by this routine. 655/// See C99 6.3.2.1p[2-4] for more details. 656QualType Sema::CheckSizeOfAlignOfOperand(QualType exprType, 657 SourceLocation OpLoc, 658 const SourceRange &ExprRange, 659 bool isSizeof) { 660 // C99 6.5.3.4p1: 661 if (isa<FunctionType>(exprType) && isSizeof) 662 // alignof(function) is allowed. 663 Diag(OpLoc, diag::ext_sizeof_function_type, ExprRange); 664 else if (exprType->isVoidType()) 665 Diag(OpLoc, diag::ext_sizeof_void_type, isSizeof ? "sizeof" : "__alignof", 666 ExprRange); 667 else if (exprType->isIncompleteType()) { 668 Diag(OpLoc, isSizeof ? diag::err_sizeof_incomplete_type : 669 diag::err_alignof_incomplete_type, 670 exprType.getAsString(), ExprRange); 671 return QualType(); // error 672 } 673 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 674 return Context.getSizeType(); 675} 676 677Action::ExprResult Sema:: 678ActOnSizeOfAlignOfTypeExpr(SourceLocation OpLoc, bool isSizeof, 679 SourceLocation LPLoc, TypeTy *Ty, 680 SourceLocation RPLoc) { 681 // If error parsing type, ignore. 682 if (Ty == 0) return true; 683 684 // Verify that this is a valid expression. 685 QualType ArgTy = QualType::getFromOpaquePtr(Ty); 686 687 QualType resultType = 688 CheckSizeOfAlignOfOperand(ArgTy, OpLoc, SourceRange(LPLoc, RPLoc),isSizeof); 689 690 if (resultType.isNull()) 691 return true; 692 return new SizeOfAlignOfTypeExpr(isSizeof, ArgTy, resultType, OpLoc, RPLoc); 693} 694 695QualType Sema::CheckRealImagOperand(Expr *&V, SourceLocation Loc) { 696 DefaultFunctionArrayConversion(V); 697 698 // These operators return the element type of a complex type. 699 if (const ComplexType *CT = V->getType()->getAsComplexType()) 700 return CT->getElementType(); 701 702 // Otherwise they pass through real integer and floating point types here. 703 if (V->getType()->isArithmeticType()) 704 return V->getType(); 705 706 // Reject anything else. 707 Diag(Loc, diag::err_realimag_invalid_type, V->getType().getAsString()); 708 return QualType(); 709} 710 711 712 713Action::ExprResult Sema::ActOnPostfixUnaryOp(SourceLocation OpLoc, 714 tok::TokenKind Kind, 715 ExprTy *Input) { 716 UnaryOperator::Opcode Opc; 717 switch (Kind) { 718 default: assert(0 && "Unknown unary op!"); 719 case tok::plusplus: Opc = UnaryOperator::PostInc; break; 720 case tok::minusminus: Opc = UnaryOperator::PostDec; break; 721 } 722 QualType result = CheckIncrementDecrementOperand((Expr *)Input, OpLoc); 723 if (result.isNull()) 724 return true; 725 return new UnaryOperator((Expr *)Input, Opc, result, OpLoc); 726} 727 728Action::ExprResult Sema:: 729ActOnArraySubscriptExpr(ExprTy *Base, SourceLocation LLoc, 730 ExprTy *Idx, SourceLocation RLoc) { 731 Expr *LHSExp = static_cast<Expr*>(Base), *RHSExp = static_cast<Expr*>(Idx); 732 733 // Perform default conversions. 734 DefaultFunctionArrayConversion(LHSExp); 735 DefaultFunctionArrayConversion(RHSExp); 736 737 QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType(); 738 739 // C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent 740 // to the expression *((e1)+(e2)). This means the array "Base" may actually be 741 // in the subscript position. As a result, we need to derive the array base 742 // and index from the expression types. 743 Expr *BaseExpr, *IndexExpr; 744 QualType ResultType; 745 if (const PointerType *PTy = LHSTy->getAsPointerType()) { 746 BaseExpr = LHSExp; 747 IndexExpr = RHSExp; 748 // FIXME: need to deal with const... 749 ResultType = PTy->getPointeeType(); 750 } else if (const PointerType *PTy = RHSTy->getAsPointerType()) { 751 // Handle the uncommon case of "123[Ptr]". 752 BaseExpr = RHSExp; 753 IndexExpr = LHSExp; 754 // FIXME: need to deal with const... 755 ResultType = PTy->getPointeeType(); 756 } else if (const VectorType *VTy = LHSTy->getAsVectorType()) { 757 BaseExpr = LHSExp; // vectors: V[123] 758 IndexExpr = RHSExp; 759 760 // Component access limited to variables (reject vec4.rg[1]). 761 if (!isa<DeclRefExpr>(BaseExpr) && !isa<ArraySubscriptExpr>(BaseExpr) && 762 !isa<ExtVectorElementExpr>(BaseExpr)) 763 return Diag(LLoc, diag::err_ext_vector_component_access, 764 SourceRange(LLoc, RLoc)); 765 // FIXME: need to deal with const... 766 ResultType = VTy->getElementType(); 767 } else { 768 return Diag(LHSExp->getLocStart(), diag::err_typecheck_subscript_value, 769 RHSExp->getSourceRange()); 770 } 771 // C99 6.5.2.1p1 772 if (!IndexExpr->getType()->isIntegerType()) 773 return Diag(IndexExpr->getLocStart(), diag::err_typecheck_subscript, 774 IndexExpr->getSourceRange()); 775 776 // C99 6.5.2.1p1: "shall have type "pointer to *object* type". In practice, 777 // the following check catches trying to index a pointer to a function (e.g. 778 // void (*)(int)) and pointers to incomplete types. Functions are not 779 // objects in C99. 780 if (!ResultType->isObjectType()) 781 return Diag(BaseExpr->getLocStart(), 782 diag::err_typecheck_subscript_not_object, 783 BaseExpr->getType().getAsString(), BaseExpr->getSourceRange()); 784 785 return new ArraySubscriptExpr(LHSExp, RHSExp, ResultType, RLoc); 786} 787 788QualType Sema:: 789CheckExtVectorComponent(QualType baseType, SourceLocation OpLoc, 790 IdentifierInfo &CompName, SourceLocation CompLoc) { 791 const ExtVectorType *vecType = baseType->getAsExtVectorType(); 792 793 // This flag determines whether or not the component is to be treated as a 794 // special name, or a regular GLSL-style component access. 795 bool SpecialComponent = false; 796 797 // The vector accessor can't exceed the number of elements. 798 const char *compStr = CompName.getName(); 799 if (strlen(compStr) > vecType->getNumElements()) { 800 Diag(OpLoc, diag::err_ext_vector_component_exceeds_length, 801 baseType.getAsString(), SourceRange(CompLoc)); 802 return QualType(); 803 } 804 805 // Check that we've found one of the special components, or that the component 806 // names must come from the same set. 807 if (!strcmp(compStr, "hi") || !strcmp(compStr, "lo") || 808 !strcmp(compStr, "e") || !strcmp(compStr, "o")) { 809 SpecialComponent = true; 810 } else if (vecType->getPointAccessorIdx(*compStr) != -1) { 811 do 812 compStr++; 813 while (*compStr && vecType->getPointAccessorIdx(*compStr) != -1); 814 } else if (vecType->getColorAccessorIdx(*compStr) != -1) { 815 do 816 compStr++; 817 while (*compStr && vecType->getColorAccessorIdx(*compStr) != -1); 818 } else if (vecType->getTextureAccessorIdx(*compStr) != -1) { 819 do 820 compStr++; 821 while (*compStr && vecType->getTextureAccessorIdx(*compStr) != -1); 822 } 823 824 if (!SpecialComponent && *compStr) { 825 // We didn't get to the end of the string. This means the component names 826 // didn't come from the same set *or* we encountered an illegal name. 827 Diag(OpLoc, diag::err_ext_vector_component_name_illegal, 828 std::string(compStr,compStr+1), SourceRange(CompLoc)); 829 return QualType(); 830 } 831 // Each component accessor can't exceed the vector type. 832 compStr = CompName.getName(); 833 while (*compStr) { 834 if (vecType->isAccessorWithinNumElements(*compStr)) 835 compStr++; 836 else 837 break; 838 } 839 if (!SpecialComponent && *compStr) { 840 // We didn't get to the end of the string. This means a component accessor 841 // exceeds the number of elements in the vector. 842 Diag(OpLoc, diag::err_ext_vector_component_exceeds_length, 843 baseType.getAsString(), SourceRange(CompLoc)); 844 return QualType(); 845 } 846 847 // If we have a special component name, verify that the current vector length 848 // is an even number, since all special component names return exactly half 849 // the elements. 850 if (SpecialComponent && (vecType->getNumElements() & 1U)) { 851 Diag(OpLoc, diag::err_ext_vector_component_requires_even, 852 baseType.getAsString(), SourceRange(CompLoc)); 853 return QualType(); 854 } 855 856 // The component accessor looks fine - now we need to compute the actual type. 857 // The vector type is implied by the component accessor. For example, 858 // vec4.b is a float, vec4.xy is a vec2, vec4.rgb is a vec3, etc. 859 // vec4.hi, vec4.lo, vec4.e, and vec4.o all return vec2. 860 unsigned CompSize = SpecialComponent ? vecType->getNumElements() / 2 861 : strlen(CompName.getName()); 862 if (CompSize == 1) 863 return vecType->getElementType(); 864 865 QualType VT = Context.getExtVectorType(vecType->getElementType(), CompSize); 866 // Now look up the TypeDefDecl from the vector type. Without this, 867 // diagostics look bad. We want extended vector types to appear built-in. 868 for (unsigned i = 0, E = ExtVectorDecls.size(); i != E; ++i) { 869 if (ExtVectorDecls[i]->getUnderlyingType() == VT) 870 return Context.getTypedefType(ExtVectorDecls[i]); 871 } 872 return VT; // should never get here (a typedef type should always be found). 873} 874 875/// constructSetterName - Return the setter name for the given 876/// identifier, i.e. "set" + Name where the initial character of Name 877/// has been capitalized. 878// FIXME: Merge with same routine in Parser. But where should this 879// live? 880static IdentifierInfo *constructSetterName(IdentifierTable &Idents, 881 const IdentifierInfo *Name) { 882 unsigned N = Name->getLength(); 883 char *SelectorName = new char[3 + N]; 884 memcpy(SelectorName, "set", 3); 885 memcpy(&SelectorName[3], Name->getName(), N); 886 SelectorName[3] = toupper(SelectorName[3]); 887 888 IdentifierInfo *Setter = 889 &Idents.get(SelectorName, &SelectorName[3 + N]); 890 delete[] SelectorName; 891 return Setter; 892} 893 894Action::ExprResult Sema:: 895ActOnMemberReferenceExpr(ExprTy *Base, SourceLocation OpLoc, 896 tok::TokenKind OpKind, SourceLocation MemberLoc, 897 IdentifierInfo &Member) { 898 Expr *BaseExpr = static_cast<Expr *>(Base); 899 assert(BaseExpr && "no record expression"); 900 901 // Perform default conversions. 902 DefaultFunctionArrayConversion(BaseExpr); 903 904 QualType BaseType = BaseExpr->getType(); 905 assert(!BaseType.isNull() && "no type for member expression"); 906 907 // Get the type being accessed in BaseType. If this is an arrow, the BaseExpr 908 // must have pointer type, and the accessed type is the pointee. 909 if (OpKind == tok::arrow) { 910 if (const PointerType *PT = BaseType->getAsPointerType()) 911 BaseType = PT->getPointeeType(); 912 else 913 return Diag(MemberLoc, diag::err_typecheck_member_reference_arrow, 914 BaseType.getAsString(), BaseExpr->getSourceRange()); 915 } 916 917 // Handle field access to simple records. This also handles access to fields 918 // of the ObjC 'id' struct. 919 if (const RecordType *RTy = BaseType->getAsRecordType()) { 920 RecordDecl *RDecl = RTy->getDecl(); 921 if (RTy->isIncompleteType()) 922 return Diag(OpLoc, diag::err_typecheck_incomplete_tag, RDecl->getName(), 923 BaseExpr->getSourceRange()); 924 // The record definition is complete, now make sure the member is valid. 925 FieldDecl *MemberDecl = RDecl->getMember(&Member); 926 if (!MemberDecl) 927 return Diag(MemberLoc, diag::err_typecheck_no_member, Member.getName(), 928 BaseExpr->getSourceRange()); 929 930 // Figure out the type of the member; see C99 6.5.2.3p3 931 // FIXME: Handle address space modifiers 932 QualType MemberType = MemberDecl->getType(); 933 unsigned combinedQualifiers = 934 MemberType.getCVRQualifiers() | BaseType.getCVRQualifiers(); 935 MemberType = MemberType.getQualifiedType(combinedQualifiers); 936 937 return new MemberExpr(BaseExpr, OpKind == tok::arrow, MemberDecl, 938 MemberLoc, MemberType); 939 } 940 941 // Handle access to Objective-C instance variables, such as "Obj->ivar" and 942 // (*Obj).ivar. 943 if (const ObjCInterfaceType *IFTy = BaseType->getAsObjCInterfaceType()) { 944 if (ObjCIvarDecl *IV = IFTy->getDecl()->lookupInstanceVariable(&Member)) 945 return new ObjCIvarRefExpr(IV, IV->getType(), MemberLoc, BaseExpr, 946 OpKind == tok::arrow); 947 return Diag(MemberLoc, diag::err_typecheck_member_reference_ivar, 948 IFTy->getDecl()->getName(), Member.getName(), 949 BaseExpr->getSourceRange()); 950 } 951 952 // Handle Objective-C property access, which is "Obj.property" where Obj is a 953 // pointer to a (potentially qualified) interface type. 954 const PointerType *PTy; 955 const ObjCInterfaceType *IFTy; 956 if (OpKind == tok::period && (PTy = BaseType->getAsPointerType()) && 957 (IFTy = PTy->getPointeeType()->getAsObjCInterfaceType())) { 958 ObjCInterfaceDecl *IFace = IFTy->getDecl(); 959 960 // Search for a declared property first. 961 if (ObjCPropertyDecl *PD = IFace->FindPropertyDeclaration(&Member)) 962 return new ObjCPropertyRefExpr(PD, PD->getType(), MemberLoc, BaseExpr); 963 964 // Check protocols on qualified interfaces. 965 for (ObjCInterfaceType::qual_iterator I = IFTy->qual_begin(), 966 E = IFTy->qual_end(); I != E; ++I) 967 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(&Member)) 968 return new ObjCPropertyRefExpr(PD, PD->getType(), MemberLoc, BaseExpr); 969 970 // If that failed, look for an "implicit" property by seeing if the nullary 971 // selector is implemented. 972 973 // FIXME: The logic for looking up nullary and unary selectors should be 974 // shared with the code in ActOnInstanceMessage. 975 976 Selector Sel = PP.getSelectorTable().getNullarySelector(&Member); 977 ObjCMethodDecl *Getter = IFace->lookupInstanceMethod(Sel); 978 979 // If this reference is in an @implementation, check for 'private' methods. 980 if (!Getter) 981 if (ObjCMethodDecl *CurMeth = getCurMethodDecl()) 982 if (ObjCInterfaceDecl *ClassDecl = CurMeth->getClassInterface()) 983 if (ObjCImplementationDecl *ImpDecl = 984 ObjCImplementations[ClassDecl->getIdentifier()]) 985 Getter = ImpDecl->getInstanceMethod(Sel); 986 987 if (Getter) { 988 // If we found a getter then this may be a valid dot-reference, we 989 // need to also look for the matching setter. 990 IdentifierInfo *SetterName = constructSetterName(PP.getIdentifierTable(), 991 &Member); 992 Selector SetterSel = PP.getSelectorTable().getUnarySelector(SetterName); 993 ObjCMethodDecl *Setter = IFace->lookupInstanceMethod(SetterSel); 994 995 if (!Setter) { 996 if (ObjCMethodDecl *CurMeth = getCurMethodDecl()) 997 if (ObjCInterfaceDecl *ClassDecl = CurMeth->getClassInterface()) 998 if (ObjCImplementationDecl *ImpDecl = 999 ObjCImplementations[ClassDecl->getIdentifier()]) 1000 Setter = ImpDecl->getInstanceMethod(SetterSel); 1001 } 1002 1003 // FIXME: There are some issues here. First, we are not 1004 // diagnosing accesses to read-only properties because we do not 1005 // know if this is a getter or setter yet. Second, we are 1006 // checking that the type of the setter matches the type we 1007 // expect. 1008 return new ObjCPropertyRefExpr(Getter, Setter, Getter->getResultType(), 1009 MemberLoc, BaseExpr); 1010 } 1011 } 1012 1013 // Handle 'field access' to vectors, such as 'V.xx'. 1014 if (BaseType->isExtVectorType() && OpKind == tok::period) { 1015 // Component access limited to variables (reject vec4.rg.g). 1016 if (!isa<DeclRefExpr>(BaseExpr) && !isa<ArraySubscriptExpr>(BaseExpr) && 1017 !isa<ExtVectorElementExpr>(BaseExpr)) 1018 return Diag(MemberLoc, diag::err_ext_vector_component_access, 1019 BaseExpr->getSourceRange()); 1020 QualType ret = CheckExtVectorComponent(BaseType, OpLoc, Member, MemberLoc); 1021 if (ret.isNull()) 1022 return true; 1023 return new ExtVectorElementExpr(ret, BaseExpr, Member, MemberLoc); 1024 } 1025 1026 return Diag(MemberLoc, diag::err_typecheck_member_reference_struct_union, 1027 BaseType.getAsString(), BaseExpr->getSourceRange()); 1028} 1029 1030/// ActOnCallExpr - Handle a call to Fn with the specified array of arguments. 1031/// This provides the location of the left/right parens and a list of comma 1032/// locations. 1033Action::ExprResult Sema:: 1034ActOnCallExpr(ExprTy *fn, SourceLocation LParenLoc, 1035 ExprTy **args, unsigned NumArgs, 1036 SourceLocation *CommaLocs, SourceLocation RParenLoc) { 1037 Expr *Fn = static_cast<Expr *>(fn); 1038 Expr **Args = reinterpret_cast<Expr**>(args); 1039 assert(Fn && "no function call expression"); 1040 FunctionDecl *FDecl = NULL; 1041 1042 // Promote the function operand. 1043 UsualUnaryConversions(Fn); 1044 1045 // If we're directly calling a function, get the declaration for 1046 // that function. 1047 if (ImplicitCastExpr *IcExpr = dyn_cast<ImplicitCastExpr>(Fn)) 1048 if (DeclRefExpr *DRExpr = dyn_cast<DeclRefExpr>(IcExpr->getSubExpr())) 1049 FDecl = dyn_cast<FunctionDecl>(DRExpr->getDecl()); 1050 1051 // Make the call expr early, before semantic checks. This guarantees cleanup 1052 // of arguments and function on error. 1053 llvm::OwningPtr<CallExpr> TheCall(new CallExpr(Fn, Args, NumArgs, 1054 Context.BoolTy, RParenLoc)); 1055 const FunctionType *FuncT; 1056 if (!Fn->getType()->isBlockPointerType()) { 1057 // C99 6.5.2.2p1 - "The expression that denotes the called function shall 1058 // have type pointer to function". 1059 const PointerType *PT = Fn->getType()->getAsPointerType(); 1060 if (PT == 0) 1061 return Diag(LParenLoc, diag::err_typecheck_call_not_function, 1062 Fn->getSourceRange()); 1063 FuncT = PT->getPointeeType()->getAsFunctionType(); 1064 } else { // This is a block call. 1065 FuncT = Fn->getType()->getAsBlockPointerType()->getPointeeType()-> 1066 getAsFunctionType(); 1067 } 1068 if (FuncT == 0) 1069 return Diag(LParenLoc, diag::err_typecheck_call_not_function, 1070 Fn->getSourceRange()); 1071 1072 // We know the result type of the call, set it. 1073 TheCall->setType(FuncT->getResultType()); 1074 1075 if (const FunctionTypeProto *Proto = dyn_cast<FunctionTypeProto>(FuncT)) { 1076 // C99 6.5.2.2p7 - the arguments are implicitly converted, as if by 1077 // assignment, to the types of the corresponding parameter, ... 1078 unsigned NumArgsInProto = Proto->getNumArgs(); 1079 unsigned NumArgsToCheck = NumArgs; 1080 1081 // If too few arguments are available (and we don't have default 1082 // arguments for the remaining parameters), don't make the call. 1083 if (NumArgs < NumArgsInProto) { 1084 if (FDecl && NumArgs >= FDecl->getMinRequiredArguments()) { 1085 // Use default arguments for missing arguments 1086 NumArgsToCheck = NumArgsInProto; 1087 TheCall->setNumArgs(NumArgsInProto); 1088 } else 1089 return Diag(RParenLoc, 1090 !Fn->getType()->isBlockPointerType() 1091 ? diag::err_typecheck_call_too_few_args 1092 : diag::err_typecheck_block_too_few_args, 1093 Fn->getSourceRange()); 1094 } 1095 1096 // If too many are passed and not variadic, error on the extras and drop 1097 // them. 1098 if (NumArgs > NumArgsInProto) { 1099 if (!Proto->isVariadic()) { 1100 Diag(Args[NumArgsInProto]->getLocStart(), 1101 !Fn->getType()->isBlockPointerType() 1102 ? diag::err_typecheck_call_too_many_args 1103 : diag::err_typecheck_block_too_many_args, 1104 Fn->getSourceRange(), 1105 SourceRange(Args[NumArgsInProto]->getLocStart(), 1106 Args[NumArgs-1]->getLocEnd())); 1107 // This deletes the extra arguments. 1108 TheCall->setNumArgs(NumArgsInProto); 1109 } 1110 NumArgsToCheck = NumArgsInProto; 1111 } 1112 1113 // Continue to check argument types (even if we have too few/many args). 1114 for (unsigned i = 0; i != NumArgsToCheck; i++) { 1115 QualType ProtoArgType = Proto->getArgType(i); 1116 1117 Expr *Arg; 1118 if (i < NumArgs) 1119 Arg = Args[i]; 1120 else 1121 Arg = new CXXDefaultArgExpr(FDecl->getParamDecl(i)); 1122 QualType ArgType = Arg->getType(); 1123 1124 // Compute implicit casts from the operand to the formal argument type. 1125 AssignConvertType ConvTy = 1126 CheckSingleAssignmentConstraints(ProtoArgType, Arg); 1127 TheCall->setArg(i, Arg); 1128 1129 if (DiagnoseAssignmentResult(ConvTy, Arg->getLocStart(), ProtoArgType, 1130 ArgType, Arg, "passing")) 1131 return true; 1132 } 1133 1134 // If this is a variadic call, handle args passed through "...". 1135 if (Proto->isVariadic()) { 1136 // Promote the arguments (C99 6.5.2.2p7). 1137 for (unsigned i = NumArgsInProto; i != NumArgs; i++) { 1138 Expr *Arg = Args[i]; 1139 DefaultArgumentPromotion(Arg); 1140 TheCall->setArg(i, Arg); 1141 } 1142 } 1143 } else { 1144 assert(isa<FunctionTypeNoProto>(FuncT) && "Unknown FunctionType!"); 1145 1146 // Promote the arguments (C99 6.5.2.2p6). 1147 for (unsigned i = 0; i != NumArgs; i++) { 1148 Expr *Arg = Args[i]; 1149 DefaultArgumentPromotion(Arg); 1150 TheCall->setArg(i, Arg); 1151 } 1152 } 1153 1154 // Do special checking on direct calls to functions. 1155 if (FDecl) 1156 return CheckFunctionCall(FDecl, TheCall.take()); 1157 1158 return TheCall.take(); 1159} 1160 1161Action::ExprResult Sema:: 1162ActOnCompoundLiteral(SourceLocation LParenLoc, TypeTy *Ty, 1163 SourceLocation RParenLoc, ExprTy *InitExpr) { 1164 assert((Ty != 0) && "ActOnCompoundLiteral(): missing type"); 1165 QualType literalType = QualType::getFromOpaquePtr(Ty); 1166 // FIXME: put back this assert when initializers are worked out. 1167 //assert((InitExpr != 0) && "ActOnCompoundLiteral(): missing expression"); 1168 Expr *literalExpr = static_cast<Expr*>(InitExpr); 1169 1170 if (literalType->isArrayType()) { 1171 if (literalType->isVariableArrayType()) 1172 return Diag(LParenLoc, 1173 diag::err_variable_object_no_init, 1174 SourceRange(LParenLoc, 1175 literalExpr->getSourceRange().getEnd())); 1176 } else if (literalType->isIncompleteType()) { 1177 return Diag(LParenLoc, 1178 diag::err_typecheck_decl_incomplete_type, 1179 literalType.getAsString(), 1180 SourceRange(LParenLoc, 1181 literalExpr->getSourceRange().getEnd())); 1182 } 1183 1184 if (CheckInitializerTypes(literalExpr, literalType)) 1185 return true; 1186 1187 bool isFileScope = !getCurFunctionDecl() && !getCurMethodDecl(); 1188 if (isFileScope) { // 6.5.2.5p3 1189 if (CheckForConstantInitializer(literalExpr, literalType)) 1190 return true; 1191 } 1192 return new CompoundLiteralExpr(LParenLoc, literalType, literalExpr, isFileScope); 1193} 1194 1195Action::ExprResult Sema:: 1196ActOnInitList(SourceLocation LBraceLoc, ExprTy **initlist, unsigned NumInit, 1197 SourceLocation RBraceLoc) { 1198 Expr **InitList = reinterpret_cast<Expr**>(initlist); 1199 1200 // Semantic analysis for initializers is done by ActOnDeclarator() and 1201 // CheckInitializer() - it requires knowledge of the object being intialized. 1202 1203 InitListExpr *E = new InitListExpr(LBraceLoc, InitList, NumInit, RBraceLoc); 1204 E->setType(Context.VoidTy); // FIXME: just a place holder for now. 1205 return E; 1206} 1207 1208/// CheckCastTypes - Check type constraints for casting between types. 1209bool Sema::CheckCastTypes(SourceRange TyR, QualType castType, Expr *&castExpr) { 1210 UsualUnaryConversions(castExpr); 1211 1212 // C99 6.5.4p2: the cast type needs to be void or scalar and the expression 1213 // type needs to be scalar. 1214 if (castType->isVoidType()) { 1215 // Cast to void allows any expr type. 1216 } else if (!castType->isScalarType() && !castType->isVectorType()) { 1217 // GCC struct/union extension: allow cast to self. 1218 if (Context.getCanonicalType(castType) != 1219 Context.getCanonicalType(castExpr->getType()) || 1220 (!castType->isStructureType() && !castType->isUnionType())) { 1221 // Reject any other conversions to non-scalar types. 1222 return Diag(TyR.getBegin(), diag::err_typecheck_cond_expect_scalar, 1223 castType.getAsString(), castExpr->getSourceRange()); 1224 } 1225 1226 // accept this, but emit an ext-warn. 1227 Diag(TyR.getBegin(), diag::ext_typecheck_cast_nonscalar, 1228 castType.getAsString(), castExpr->getSourceRange()); 1229 } else if (!castExpr->getType()->isScalarType() && 1230 !castExpr->getType()->isVectorType()) { 1231 return Diag(castExpr->getLocStart(), 1232 diag::err_typecheck_expect_scalar_operand, 1233 castExpr->getType().getAsString(),castExpr->getSourceRange()); 1234 } else if (castExpr->getType()->isVectorType()) { 1235 if (CheckVectorCast(TyR, castExpr->getType(), castType)) 1236 return true; 1237 } else if (castType->isVectorType()) { 1238 if (CheckVectorCast(TyR, castType, castExpr->getType())) 1239 return true; 1240 } 1241 return false; 1242} 1243 1244bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty) { 1245 assert(VectorTy->isVectorType() && "Not a vector type!"); 1246 1247 if (Ty->isVectorType() || Ty->isIntegerType()) { 1248 if (Context.getTypeSize(VectorTy) != Context.getTypeSize(Ty)) 1249 return Diag(R.getBegin(), 1250 Ty->isVectorType() ? 1251 diag::err_invalid_conversion_between_vectors : 1252 diag::err_invalid_conversion_between_vector_and_integer, 1253 VectorTy.getAsString().c_str(), 1254 Ty.getAsString().c_str(), R); 1255 } else 1256 return Diag(R.getBegin(), 1257 diag::err_invalid_conversion_between_vector_and_scalar, 1258 VectorTy.getAsString().c_str(), 1259 Ty.getAsString().c_str(), R); 1260 1261 return false; 1262} 1263 1264Action::ExprResult Sema:: 1265ActOnCastExpr(SourceLocation LParenLoc, TypeTy *Ty, 1266 SourceLocation RParenLoc, ExprTy *Op) { 1267 assert((Ty != 0) && (Op != 0) && "ActOnCastExpr(): missing type or expr"); 1268 1269 Expr *castExpr = static_cast<Expr*>(Op); 1270 QualType castType = QualType::getFromOpaquePtr(Ty); 1271 1272 if (CheckCastTypes(SourceRange(LParenLoc, RParenLoc), castType, castExpr)) 1273 return true; 1274 return new ExplicitCastExpr(castType, castExpr, LParenLoc); 1275} 1276 1277/// Note that lex is not null here, even if this is the gnu "x ?: y" extension. 1278/// In that case, lex = cond. 1279inline QualType Sema::CheckConditionalOperands( // C99 6.5.15 1280 Expr *&cond, Expr *&lex, Expr *&rex, SourceLocation questionLoc) { 1281 UsualUnaryConversions(cond); 1282 UsualUnaryConversions(lex); 1283 UsualUnaryConversions(rex); 1284 QualType condT = cond->getType(); 1285 QualType lexT = lex->getType(); 1286 QualType rexT = rex->getType(); 1287 1288 // first, check the condition. 1289 if (!condT->isScalarType()) { // C99 6.5.15p2 1290 Diag(cond->getLocStart(), diag::err_typecheck_cond_expect_scalar, 1291 condT.getAsString()); 1292 return QualType(); 1293 } 1294 1295 // Now check the two expressions. 1296 1297 // If both operands have arithmetic type, do the usual arithmetic conversions 1298 // to find a common type: C99 6.5.15p3,5. 1299 if (lexT->isArithmeticType() && rexT->isArithmeticType()) { 1300 UsualArithmeticConversions(lex, rex); 1301 return lex->getType(); 1302 } 1303 1304 // If both operands are the same structure or union type, the result is that 1305 // type. 1306 if (const RecordType *LHSRT = lexT->getAsRecordType()) { // C99 6.5.15p3 1307 if (const RecordType *RHSRT = rexT->getAsRecordType()) 1308 if (LHSRT->getDecl() == RHSRT->getDecl()) 1309 // "If both the operands have structure or union type, the result has 1310 // that type." This implies that CV qualifiers are dropped. 1311 return lexT.getUnqualifiedType(); 1312 } 1313 1314 // C99 6.5.15p5: "If both operands have void type, the result has void type." 1315 // The following || allows only one side to be void (a GCC-ism). 1316 if (lexT->isVoidType() || rexT->isVoidType()) { 1317 if (!lexT->isVoidType()) 1318 Diag(rex->getLocStart(), diag::ext_typecheck_cond_one_void, 1319 rex->getSourceRange()); 1320 if (!rexT->isVoidType()) 1321 Diag(lex->getLocStart(), diag::ext_typecheck_cond_one_void, 1322 lex->getSourceRange()); 1323 ImpCastExprToType(lex, Context.VoidTy); 1324 ImpCastExprToType(rex, Context.VoidTy); 1325 return Context.VoidTy; 1326 } 1327 // C99 6.5.15p6 - "if one operand is a null pointer constant, the result has 1328 // the type of the other operand." 1329 if ((lexT->isPointerType() || lexT->isBlockPointerType() || 1330 Context.isObjCObjectPointerType(lexT)) && 1331 rex->isNullPointerConstant(Context)) { 1332 ImpCastExprToType(rex, lexT); // promote the null to a pointer. 1333 return lexT; 1334 } 1335 if ((rexT->isPointerType() || rexT->isBlockPointerType() || 1336 Context.isObjCObjectPointerType(rexT)) && 1337 lex->isNullPointerConstant(Context)) { 1338 ImpCastExprToType(lex, rexT); // promote the null to a pointer. 1339 return rexT; 1340 } 1341 // Handle the case where both operands are pointers before we handle null 1342 // pointer constants in case both operands are null pointer constants. 1343 if (const PointerType *LHSPT = lexT->getAsPointerType()) { // C99 6.5.15p3,6 1344 if (const PointerType *RHSPT = rexT->getAsPointerType()) { 1345 // get the "pointed to" types 1346 QualType lhptee = LHSPT->getPointeeType(); 1347 QualType rhptee = RHSPT->getPointeeType(); 1348 1349 // ignore qualifiers on void (C99 6.5.15p3, clause 6) 1350 if (lhptee->isVoidType() && 1351 rhptee->isIncompleteOrObjectType()) { 1352 // Figure out necessary qualifiers (C99 6.5.15p6) 1353 QualType destPointee=lhptee.getQualifiedType(rhptee.getCVRQualifiers()); 1354 QualType destType = Context.getPointerType(destPointee); 1355 ImpCastExprToType(lex, destType); // add qualifiers if necessary 1356 ImpCastExprToType(rex, destType); // promote to void* 1357 return destType; 1358 } 1359 if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) { 1360 QualType destPointee=rhptee.getQualifiedType(lhptee.getCVRQualifiers()); 1361 QualType destType = Context.getPointerType(destPointee); 1362 ImpCastExprToType(lex, destType); // add qualifiers if necessary 1363 ImpCastExprToType(rex, destType); // promote to void* 1364 return destType; 1365 } 1366 1367 QualType compositeType = lexT; 1368 1369 // If either type is an Objective-C object type then check 1370 // compatibility according to Objective-C. 1371 if (Context.isObjCObjectPointerType(lexT) || 1372 Context.isObjCObjectPointerType(rexT)) { 1373 // If both operands are interfaces and either operand can be 1374 // assigned to the other, use that type as the composite 1375 // type. This allows 1376 // xxx ? (A*) a : (B*) b 1377 // where B is a subclass of A. 1378 // 1379 // Additionally, as for assignment, if either type is 'id' 1380 // allow silent coercion. Finally, if the types are 1381 // incompatible then make sure to use 'id' as the composite 1382 // type so the result is acceptable for sending messages to. 1383 1384 // FIXME: This code should not be localized to here. Also this 1385 // should use a compatible check instead of abusing the 1386 // canAssignObjCInterfaces code. 1387 const ObjCInterfaceType* LHSIface = lhptee->getAsObjCInterfaceType(); 1388 const ObjCInterfaceType* RHSIface = rhptee->getAsObjCInterfaceType(); 1389 if (LHSIface && RHSIface && 1390 Context.canAssignObjCInterfaces(LHSIface, RHSIface)) { 1391 compositeType = lexT; 1392 } else if (LHSIface && RHSIface && 1393 Context.canAssignObjCInterfaces(LHSIface, RHSIface)) { 1394 compositeType = rexT; 1395 } else if (Context.isObjCIdType(lhptee) || 1396 Context.isObjCIdType(rhptee)) { 1397 // FIXME: This code looks wrong, because isObjCIdType checks 1398 // the struct but getObjCIdType returns the pointer to 1399 // struct. This is horrible and should be fixed. 1400 compositeType = Context.getObjCIdType(); 1401 } else { 1402 QualType incompatTy = Context.getObjCIdType(); 1403 ImpCastExprToType(lex, incompatTy); 1404 ImpCastExprToType(rex, incompatTy); 1405 return incompatTy; 1406 } 1407 } else if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 1408 rhptee.getUnqualifiedType())) { 1409 Diag(questionLoc, diag::warn_typecheck_cond_incompatible_pointers, 1410 lexT.getAsString(), rexT.getAsString(), 1411 lex->getSourceRange(), rex->getSourceRange()); 1412 // In this situation, we assume void* type. No especially good 1413 // reason, but this is what gcc does, and we do have to pick 1414 // to get a consistent AST. 1415 QualType incompatTy = Context.getPointerType(Context.VoidTy); 1416 ImpCastExprToType(lex, incompatTy); 1417 ImpCastExprToType(rex, incompatTy); 1418 return incompatTy; 1419 } 1420 // The pointer types are compatible. 1421 // C99 6.5.15p6: If both operands are pointers to compatible types *or* to 1422 // differently qualified versions of compatible types, the result type is 1423 // a pointer to an appropriately qualified version of the *composite* 1424 // type. 1425 // FIXME: Need to calculate the composite type. 1426 // FIXME: Need to add qualifiers 1427 ImpCastExprToType(lex, compositeType); 1428 ImpCastExprToType(rex, compositeType); 1429 return compositeType; 1430 } 1431 } 1432 // Need to handle "id<xx>" explicitly. Unlike "id", whose canonical type 1433 // evaluates to "struct objc_object *" (and is handled above when comparing 1434 // id with statically typed objects). 1435 if (lexT->isObjCQualifiedIdType() || rexT->isObjCQualifiedIdType()) { 1436 // GCC allows qualified id and any Objective-C type to devolve to 1437 // id. Currently localizing to here until clear this should be 1438 // part of ObjCQualifiedIdTypesAreCompatible. 1439 if (ObjCQualifiedIdTypesAreCompatible(lexT, rexT, true) || 1440 (lexT->isObjCQualifiedIdType() && 1441 Context.isObjCObjectPointerType(rexT)) || 1442 (rexT->isObjCQualifiedIdType() && 1443 Context.isObjCObjectPointerType(lexT))) { 1444 // FIXME: This is not the correct composite type. This only 1445 // happens to work because id can more or less be used anywhere, 1446 // however this may change the type of method sends. 1447 // FIXME: gcc adds some type-checking of the arguments and emits 1448 // (confusing) incompatible comparison warnings in some 1449 // cases. Investigate. 1450 QualType compositeType = Context.getObjCIdType(); 1451 ImpCastExprToType(lex, compositeType); 1452 ImpCastExprToType(rex, compositeType); 1453 return compositeType; 1454 } 1455 } 1456 1457 // Selection between block pointer types is ok as long as they are the same. 1458 if (lexT->isBlockPointerType() && rexT->isBlockPointerType() && 1459 Context.getCanonicalType(lexT) == Context.getCanonicalType(rexT)) 1460 return lexT; 1461 1462 // Otherwise, the operands are not compatible. 1463 Diag(questionLoc, diag::err_typecheck_cond_incompatible_operands, 1464 lexT.getAsString(), rexT.getAsString(), 1465 lex->getSourceRange(), rex->getSourceRange()); 1466 return QualType(); 1467} 1468 1469/// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null 1470/// in the case of a the GNU conditional expr extension. 1471Action::ExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc, 1472 SourceLocation ColonLoc, 1473 ExprTy *Cond, ExprTy *LHS, 1474 ExprTy *RHS) { 1475 Expr *CondExpr = (Expr *) Cond; 1476 Expr *LHSExpr = (Expr *) LHS, *RHSExpr = (Expr *) RHS; 1477 1478 // If this is the gnu "x ?: y" extension, analyze the types as though the LHS 1479 // was the condition. 1480 bool isLHSNull = LHSExpr == 0; 1481 if (isLHSNull) 1482 LHSExpr = CondExpr; 1483 1484 QualType result = CheckConditionalOperands(CondExpr, LHSExpr, 1485 RHSExpr, QuestionLoc); 1486 if (result.isNull()) 1487 return true; 1488 return new ConditionalOperator(CondExpr, isLHSNull ? 0 : LHSExpr, 1489 RHSExpr, result); 1490} 1491 1492 1493// CheckPointerTypesForAssignment - This is a very tricky routine (despite 1494// being closely modeled after the C99 spec:-). The odd characteristic of this 1495// routine is it effectively iqnores the qualifiers on the top level pointee. 1496// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3]. 1497// FIXME: add a couple examples in this comment. 1498Sema::AssignConvertType 1499Sema::CheckPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 1500 QualType lhptee, rhptee; 1501 1502 // get the "pointed to" type (ignoring qualifiers at the top level) 1503 lhptee = lhsType->getAsPointerType()->getPointeeType(); 1504 rhptee = rhsType->getAsPointerType()->getPointeeType(); 1505 1506 // make sure we operate on the canonical type 1507 lhptee = Context.getCanonicalType(lhptee); 1508 rhptee = Context.getCanonicalType(rhptee); 1509 1510 AssignConvertType ConvTy = Compatible; 1511 1512 // C99 6.5.16.1p1: This following citation is common to constraints 1513 // 3 & 4 (below). ...and the type *pointed to* by the left has all the 1514 // qualifiers of the type *pointed to* by the right; 1515 // FIXME: Handle ASQualType 1516 if ((lhptee.getCVRQualifiers() & rhptee.getCVRQualifiers()) != 1517 rhptee.getCVRQualifiers()) 1518 ConvTy = CompatiblePointerDiscardsQualifiers; 1519 1520 // C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or 1521 // incomplete type and the other is a pointer to a qualified or unqualified 1522 // version of void... 1523 if (lhptee->isVoidType()) { 1524 if (rhptee->isIncompleteOrObjectType()) 1525 return ConvTy; 1526 1527 // As an extension, we allow cast to/from void* to function pointer. 1528 assert(rhptee->isFunctionType()); 1529 return FunctionVoidPointer; 1530 } 1531 1532 if (rhptee->isVoidType()) { 1533 if (lhptee->isIncompleteOrObjectType()) 1534 return ConvTy; 1535 1536 // As an extension, we allow cast to/from void* to function pointer. 1537 assert(lhptee->isFunctionType()); 1538 return FunctionVoidPointer; 1539 } 1540 1541 // Check for ObjC interfaces 1542 const ObjCInterfaceType* LHSIface = lhptee->getAsObjCInterfaceType(); 1543 const ObjCInterfaceType* RHSIface = rhptee->getAsObjCInterfaceType(); 1544 if (LHSIface && RHSIface && 1545 Context.canAssignObjCInterfaces(LHSIface, RHSIface)) 1546 return ConvTy; 1547 1548 // ID acts sort of like void* for ObjC interfaces 1549 if (LHSIface && Context.isObjCIdType(rhptee)) 1550 return ConvTy; 1551 if (RHSIface && Context.isObjCIdType(lhptee)) 1552 return ConvTy; 1553 1554 // C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or 1555 // unqualified versions of compatible types, ... 1556 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 1557 rhptee.getUnqualifiedType())) 1558 return IncompatiblePointer; // this "trumps" PointerAssignDiscardsQualifiers 1559 return ConvTy; 1560} 1561 1562/// CheckBlockPointerTypesForAssignment - This routine determines whether two 1563/// block pointer types are compatible or whether a block and normal pointer 1564/// are compatible. It is more restrict than comparing two function pointer 1565// types. 1566Sema::AssignConvertType 1567Sema::CheckBlockPointerTypesForAssignment(QualType lhsType, 1568 QualType rhsType) { 1569 QualType lhptee, rhptee; 1570 1571 // get the "pointed to" type (ignoring qualifiers at the top level) 1572 lhptee = lhsType->getAsBlockPointerType()->getPointeeType(); 1573 rhptee = rhsType->getAsBlockPointerType()->getPointeeType(); 1574 1575 // make sure we operate on the canonical type 1576 lhptee = Context.getCanonicalType(lhptee); 1577 rhptee = Context.getCanonicalType(rhptee); 1578 1579 AssignConvertType ConvTy = Compatible; 1580 1581 // For blocks we enforce that qualifiers are identical. 1582 if (lhptee.getCVRQualifiers() != rhptee.getCVRQualifiers()) 1583 ConvTy = CompatiblePointerDiscardsQualifiers; 1584 1585 if (!Context.typesAreBlockCompatible(lhptee, rhptee)) 1586 return IncompatibleBlockPointer; 1587 return ConvTy; 1588} 1589 1590/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently 1591/// has code to accommodate several GCC extensions when type checking 1592/// pointers. Here are some objectionable examples that GCC considers warnings: 1593/// 1594/// int a, *pint; 1595/// short *pshort; 1596/// struct foo *pfoo; 1597/// 1598/// pint = pshort; // warning: assignment from incompatible pointer type 1599/// a = pint; // warning: assignment makes integer from pointer without a cast 1600/// pint = a; // warning: assignment makes pointer from integer without a cast 1601/// pint = pfoo; // warning: assignment from incompatible pointer type 1602/// 1603/// As a result, the code for dealing with pointers is more complex than the 1604/// C99 spec dictates. 1605/// 1606Sema::AssignConvertType 1607Sema::CheckAssignmentConstraints(QualType lhsType, QualType rhsType) { 1608 // Get canonical types. We're not formatting these types, just comparing 1609 // them. 1610 lhsType = Context.getCanonicalType(lhsType).getUnqualifiedType(); 1611 rhsType = Context.getCanonicalType(rhsType).getUnqualifiedType(); 1612 1613 if (lhsType == rhsType) 1614 return Compatible; // Common case: fast path an exact match. 1615 1616 if (lhsType->isReferenceType() || rhsType->isReferenceType()) { 1617 if (Context.typesAreCompatible(lhsType, rhsType)) 1618 return Compatible; 1619 return Incompatible; 1620 } 1621 1622 if (lhsType->isObjCQualifiedIdType() || rhsType->isObjCQualifiedIdType()) { 1623 if (ObjCQualifiedIdTypesAreCompatible(lhsType, rhsType, false)) 1624 return Compatible; 1625 // Relax integer conversions like we do for pointers below. 1626 if (rhsType->isIntegerType()) 1627 return IntToPointer; 1628 if (lhsType->isIntegerType()) 1629 return PointerToInt; 1630 return Incompatible; 1631 } 1632 1633 if (lhsType->isVectorType() || rhsType->isVectorType()) { 1634 // For ExtVector, allow vector splats; float -> <n x float> 1635 if (const ExtVectorType *LV = lhsType->getAsExtVectorType()) 1636 if (LV->getElementType() == rhsType) 1637 return Compatible; 1638 1639 // If we are allowing lax vector conversions, and LHS and RHS are both 1640 // vectors, the total size only needs to be the same. This is a bitcast; 1641 // no bits are changed but the result type is different. 1642 if (getLangOptions().LaxVectorConversions && 1643 lhsType->isVectorType() && rhsType->isVectorType()) { 1644 if (Context.getTypeSize(lhsType) == Context.getTypeSize(rhsType)) 1645 return Compatible; 1646 } 1647 return Incompatible; 1648 } 1649 1650 if (lhsType->isArithmeticType() && rhsType->isArithmeticType()) 1651 return Compatible; 1652 1653 if (isa<PointerType>(lhsType)) { 1654 if (rhsType->isIntegerType()) 1655 return IntToPointer; 1656 1657 if (isa<PointerType>(rhsType)) 1658 return CheckPointerTypesForAssignment(lhsType, rhsType); 1659 1660 if (rhsType->getAsBlockPointerType()) { 1661 if (lhsType->getAsPointerType()->getPointeeType()->isVoidType()) 1662 return BlockVoidPointer; 1663 1664 // Treat block pointers as objects. 1665 if (getLangOptions().ObjC1 && 1666 lhsType == Context.getCanonicalType(Context.getObjCIdType())) 1667 return Compatible; 1668 } 1669 return Incompatible; 1670 } 1671 1672 if (isa<BlockPointerType>(lhsType)) { 1673 if (rhsType->isIntegerType()) 1674 return IntToPointer; 1675 1676 // Treat block pointers as objects. 1677 if (getLangOptions().ObjC1 && 1678 rhsType == Context.getCanonicalType(Context.getObjCIdType())) 1679 return Compatible; 1680 1681 if (rhsType->isBlockPointerType()) 1682 return CheckBlockPointerTypesForAssignment(lhsType, rhsType); 1683 1684 if (const PointerType *RHSPT = rhsType->getAsPointerType()) { 1685 if (RHSPT->getPointeeType()->isVoidType()) 1686 return BlockVoidPointer; 1687 } 1688 return Incompatible; 1689 } 1690 1691 if (isa<PointerType>(rhsType)) { 1692 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 1693 if (lhsType == Context.BoolTy) 1694 return Compatible; 1695 1696 if (lhsType->isIntegerType()) 1697 return PointerToInt; 1698 1699 if (isa<PointerType>(lhsType)) 1700 return CheckPointerTypesForAssignment(lhsType, rhsType); 1701 1702 if (isa<BlockPointerType>(lhsType) && 1703 rhsType->getAsPointerType()->getPointeeType()->isVoidType()) 1704 return BlockVoidPointer; 1705 return Incompatible; 1706 } 1707 1708 if (isa<TagType>(lhsType) && isa<TagType>(rhsType)) { 1709 if (Context.typesAreCompatible(lhsType, rhsType)) 1710 return Compatible; 1711 } 1712 return Incompatible; 1713} 1714 1715Sema::AssignConvertType 1716Sema::CheckSingleAssignmentConstraints(QualType lhsType, Expr *&rExpr) { 1717 // C99 6.5.16.1p1: the left operand is a pointer and the right is 1718 // a null pointer constant. 1719 if ((lhsType->isPointerType() || lhsType->isObjCQualifiedIdType() || 1720 lhsType->isBlockPointerType()) 1721 && rExpr->isNullPointerConstant(Context)) { 1722 ImpCastExprToType(rExpr, lhsType); 1723 return Compatible; 1724 } 1725 1726 // We don't allow conversion of non-null-pointer constants to integers. 1727 if (lhsType->isBlockPointerType() && rExpr->getType()->isIntegerType()) 1728 return IntToBlockPointer; 1729 1730 // This check seems unnatural, however it is necessary to ensure the proper 1731 // conversion of functions/arrays. If the conversion were done for all 1732 // DeclExpr's (created by ActOnIdentifierExpr), it would mess up the unary 1733 // expressions that surpress this implicit conversion (&, sizeof). 1734 // 1735 // Suppress this for references: C99 8.5.3p5. FIXME: revisit when references 1736 // are better understood. 1737 if (!lhsType->isReferenceType()) 1738 DefaultFunctionArrayConversion(rExpr); 1739 1740 Sema::AssignConvertType result = 1741 CheckAssignmentConstraints(lhsType, rExpr->getType()); 1742 1743 // C99 6.5.16.1p2: The value of the right operand is converted to the 1744 // type of the assignment expression. 1745 if (rExpr->getType() != lhsType) 1746 ImpCastExprToType(rExpr, lhsType); 1747 return result; 1748} 1749 1750Sema::AssignConvertType 1751Sema::CheckCompoundAssignmentConstraints(QualType lhsType, QualType rhsType) { 1752 return CheckAssignmentConstraints(lhsType, rhsType); 1753} 1754 1755QualType Sema::InvalidOperands(SourceLocation loc, Expr *&lex, Expr *&rex) { 1756 Diag(loc, diag::err_typecheck_invalid_operands, 1757 lex->getType().getAsString(), rex->getType().getAsString(), 1758 lex->getSourceRange(), rex->getSourceRange()); 1759 return QualType(); 1760} 1761 1762inline QualType Sema::CheckVectorOperands(SourceLocation loc, Expr *&lex, 1763 Expr *&rex) { 1764 // For conversion purposes, we ignore any qualifiers. 1765 // For example, "const float" and "float" are equivalent. 1766 QualType lhsType = 1767 Context.getCanonicalType(lex->getType()).getUnqualifiedType(); 1768 QualType rhsType = 1769 Context.getCanonicalType(rex->getType()).getUnqualifiedType(); 1770 1771 // If the vector types are identical, return. 1772 if (lhsType == rhsType) 1773 return lhsType; 1774 1775 // Handle the case of a vector & extvector type of the same size and element 1776 // type. It would be nice if we only had one vector type someday. 1777 if (getLangOptions().LaxVectorConversions) 1778 if (const VectorType *LV = lhsType->getAsVectorType()) 1779 if (const VectorType *RV = rhsType->getAsVectorType()) 1780 if (LV->getElementType() == RV->getElementType() && 1781 LV->getNumElements() == RV->getNumElements()) 1782 return lhsType->isExtVectorType() ? lhsType : rhsType; 1783 1784 // If the lhs is an extended vector and the rhs is a scalar of the same type 1785 // or a literal, promote the rhs to the vector type. 1786 if (const ExtVectorType *V = lhsType->getAsExtVectorType()) { 1787 QualType eltType = V->getElementType(); 1788 1789 if ((eltType->getAsBuiltinType() == rhsType->getAsBuiltinType()) || 1790 (eltType->isIntegerType() && isa<IntegerLiteral>(rex)) || 1791 (eltType->isFloatingType() && isa<FloatingLiteral>(rex))) { 1792 ImpCastExprToType(rex, lhsType); 1793 return lhsType; 1794 } 1795 } 1796 1797 // If the rhs is an extended vector and the lhs is a scalar of the same type, 1798 // promote the lhs to the vector type. 1799 if (const ExtVectorType *V = rhsType->getAsExtVectorType()) { 1800 QualType eltType = V->getElementType(); 1801 1802 if ((eltType->getAsBuiltinType() == lhsType->getAsBuiltinType()) || 1803 (eltType->isIntegerType() && isa<IntegerLiteral>(lex)) || 1804 (eltType->isFloatingType() && isa<FloatingLiteral>(lex))) { 1805 ImpCastExprToType(lex, rhsType); 1806 return rhsType; 1807 } 1808 } 1809 1810 // You cannot convert between vector values of different size. 1811 Diag(loc, diag::err_typecheck_vector_not_convertable, 1812 lex->getType().getAsString(), rex->getType().getAsString(), 1813 lex->getSourceRange(), rex->getSourceRange()); 1814 return QualType(); 1815} 1816 1817inline QualType Sema::CheckMultiplyDivideOperands( 1818 Expr *&lex, Expr *&rex, SourceLocation loc, bool isCompAssign) 1819{ 1820 QualType lhsType = lex->getType(), rhsType = rex->getType(); 1821 1822 if (lhsType->isVectorType() || rhsType->isVectorType()) 1823 return CheckVectorOperands(loc, lex, rex); 1824 1825 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 1826 1827 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 1828 return compType; 1829 return InvalidOperands(loc, lex, rex); 1830} 1831 1832inline QualType Sema::CheckRemainderOperands( 1833 Expr *&lex, Expr *&rex, SourceLocation loc, bool isCompAssign) 1834{ 1835 QualType lhsType = lex->getType(), rhsType = rex->getType(); 1836 1837 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 1838 1839 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 1840 return compType; 1841 return InvalidOperands(loc, lex, rex); 1842} 1843 1844inline QualType Sema::CheckAdditionOperands( // C99 6.5.6 1845 Expr *&lex, Expr *&rex, SourceLocation loc, bool isCompAssign) 1846{ 1847 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 1848 return CheckVectorOperands(loc, lex, rex); 1849 1850 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 1851 1852 // handle the common case first (both operands are arithmetic). 1853 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 1854 return compType; 1855 1856 // Put any potential pointer into PExp 1857 Expr* PExp = lex, *IExp = rex; 1858 if (IExp->getType()->isPointerType()) 1859 std::swap(PExp, IExp); 1860 1861 if (const PointerType* PTy = PExp->getType()->getAsPointerType()) { 1862 if (IExp->getType()->isIntegerType()) { 1863 // Check for arithmetic on pointers to incomplete types 1864 if (!PTy->getPointeeType()->isObjectType()) { 1865 if (PTy->getPointeeType()->isVoidType()) { 1866 Diag(loc, diag::ext_gnu_void_ptr, 1867 lex->getSourceRange(), rex->getSourceRange()); 1868 } else { 1869 Diag(loc, diag::err_typecheck_arithmetic_incomplete_type, 1870 lex->getType().getAsString(), lex->getSourceRange()); 1871 return QualType(); 1872 } 1873 } 1874 return PExp->getType(); 1875 } 1876 } 1877 1878 return InvalidOperands(loc, lex, rex); 1879} 1880 1881// C99 6.5.6 1882QualType Sema::CheckSubtractionOperands(Expr *&lex, Expr *&rex, 1883 SourceLocation loc, bool isCompAssign) { 1884 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 1885 return CheckVectorOperands(loc, lex, rex); 1886 1887 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 1888 1889 // Enforce type constraints: C99 6.5.6p3. 1890 1891 // Handle the common case first (both operands are arithmetic). 1892 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 1893 return compType; 1894 1895 // Either ptr - int or ptr - ptr. 1896 if (const PointerType *LHSPTy = lex->getType()->getAsPointerType()) { 1897 QualType lpointee = LHSPTy->getPointeeType(); 1898 1899 // The LHS must be an object type, not incomplete, function, etc. 1900 if (!lpointee->isObjectType()) { 1901 // Handle the GNU void* extension. 1902 if (lpointee->isVoidType()) { 1903 Diag(loc, diag::ext_gnu_void_ptr, 1904 lex->getSourceRange(), rex->getSourceRange()); 1905 } else { 1906 Diag(loc, diag::err_typecheck_sub_ptr_object, 1907 lex->getType().getAsString(), lex->getSourceRange()); 1908 return QualType(); 1909 } 1910 } 1911 1912 // The result type of a pointer-int computation is the pointer type. 1913 if (rex->getType()->isIntegerType()) 1914 return lex->getType(); 1915 1916 // Handle pointer-pointer subtractions. 1917 if (const PointerType *RHSPTy = rex->getType()->getAsPointerType()) { 1918 QualType rpointee = RHSPTy->getPointeeType(); 1919 1920 // RHS must be an object type, unless void (GNU). 1921 if (!rpointee->isObjectType()) { 1922 // Handle the GNU void* extension. 1923 if (rpointee->isVoidType()) { 1924 if (!lpointee->isVoidType()) 1925 Diag(loc, diag::ext_gnu_void_ptr, 1926 lex->getSourceRange(), rex->getSourceRange()); 1927 } else { 1928 Diag(loc, diag::err_typecheck_sub_ptr_object, 1929 rex->getType().getAsString(), rex->getSourceRange()); 1930 return QualType(); 1931 } 1932 } 1933 1934 // Pointee types must be compatible. 1935 if (!Context.typesAreCompatible( 1936 Context.getCanonicalType(lpointee).getUnqualifiedType(), 1937 Context.getCanonicalType(rpointee).getUnqualifiedType())) { 1938 Diag(loc, diag::err_typecheck_sub_ptr_compatible, 1939 lex->getType().getAsString(), rex->getType().getAsString(), 1940 lex->getSourceRange(), rex->getSourceRange()); 1941 return QualType(); 1942 } 1943 1944 return Context.getPointerDiffType(); 1945 } 1946 } 1947 1948 return InvalidOperands(loc, lex, rex); 1949} 1950 1951// C99 6.5.7 1952QualType Sema::CheckShiftOperands(Expr *&lex, Expr *&rex, SourceLocation loc, 1953 bool isCompAssign) { 1954 // C99 6.5.7p2: Each of the operands shall have integer type. 1955 if (!lex->getType()->isIntegerType() || !rex->getType()->isIntegerType()) 1956 return InvalidOperands(loc, lex, rex); 1957 1958 // Shifts don't perform usual arithmetic conversions, they just do integer 1959 // promotions on each operand. C99 6.5.7p3 1960 if (!isCompAssign) 1961 UsualUnaryConversions(lex); 1962 UsualUnaryConversions(rex); 1963 1964 // "The type of the result is that of the promoted left operand." 1965 return lex->getType(); 1966} 1967 1968static bool areComparableObjCInterfaces(QualType LHS, QualType RHS, 1969 ASTContext& Context) { 1970 const ObjCInterfaceType* LHSIface = LHS->getAsObjCInterfaceType(); 1971 const ObjCInterfaceType* RHSIface = RHS->getAsObjCInterfaceType(); 1972 // ID acts sort of like void* for ObjC interfaces 1973 if (LHSIface && Context.isObjCIdType(RHS)) 1974 return true; 1975 if (RHSIface && Context.isObjCIdType(LHS)) 1976 return true; 1977 if (!LHSIface || !RHSIface) 1978 return false; 1979 return Context.canAssignObjCInterfaces(LHSIface, RHSIface) || 1980 Context.canAssignObjCInterfaces(RHSIface, LHSIface); 1981} 1982 1983// C99 6.5.8 1984QualType Sema::CheckCompareOperands(Expr *&lex, Expr *&rex, SourceLocation loc, 1985 bool isRelational) { 1986 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 1987 return CheckVectorCompareOperands(lex, rex, loc, isRelational); 1988 1989 // C99 6.5.8p3 / C99 6.5.9p4 1990 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 1991 UsualArithmeticConversions(lex, rex); 1992 else { 1993 UsualUnaryConversions(lex); 1994 UsualUnaryConversions(rex); 1995 } 1996 QualType lType = lex->getType(); 1997 QualType rType = rex->getType(); 1998 1999 // For non-floating point types, check for self-comparisons of the form 2000 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 2001 // often indicate logic errors in the program. 2002 if (!lType->isFloatingType()) { 2003 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(lex->IgnoreParens())) 2004 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(rex->IgnoreParens())) 2005 if (DRL->getDecl() == DRR->getDecl()) 2006 Diag(loc, diag::warn_selfcomparison); 2007 } 2008 2009 if (isRelational) { 2010 if (lType->isRealType() && rType->isRealType()) 2011 return Context.IntTy; 2012 } else { 2013 // Check for comparisons of floating point operands using != and ==. 2014 if (lType->isFloatingType()) { 2015 assert (rType->isFloatingType()); 2016 CheckFloatComparison(loc,lex,rex); 2017 } 2018 2019 if (lType->isArithmeticType() && rType->isArithmeticType()) 2020 return Context.IntTy; 2021 } 2022 2023 bool LHSIsNull = lex->isNullPointerConstant(Context); 2024 bool RHSIsNull = rex->isNullPointerConstant(Context); 2025 2026 // All of the following pointer related warnings are GCC extensions, except 2027 // when handling null pointer constants. One day, we can consider making them 2028 // errors (when -pedantic-errors is enabled). 2029 if (lType->isPointerType() && rType->isPointerType()) { // C99 6.5.8p2 2030 QualType LCanPointeeTy = 2031 Context.getCanonicalType(lType->getAsPointerType()->getPointeeType()); 2032 QualType RCanPointeeTy = 2033 Context.getCanonicalType(rType->getAsPointerType()->getPointeeType()); 2034 2035 if (!LHSIsNull && !RHSIsNull && // C99 6.5.9p2 2036 !LCanPointeeTy->isVoidType() && !RCanPointeeTy->isVoidType() && 2037 !Context.typesAreCompatible(LCanPointeeTy.getUnqualifiedType(), 2038 RCanPointeeTy.getUnqualifiedType()) && 2039 !areComparableObjCInterfaces(LCanPointeeTy, RCanPointeeTy, Context)) { 2040 Diag(loc, diag::ext_typecheck_comparison_of_distinct_pointers, 2041 lType.getAsString(), rType.getAsString(), 2042 lex->getSourceRange(), rex->getSourceRange()); 2043 } 2044 ImpCastExprToType(rex, lType); // promote the pointer to pointer 2045 return Context.IntTy; 2046 } 2047 // Handle block pointer types. 2048 if (lType->isBlockPointerType() && rType->isBlockPointerType()) { 2049 QualType lpointee = lType->getAsBlockPointerType()->getPointeeType(); 2050 QualType rpointee = rType->getAsBlockPointerType()->getPointeeType(); 2051 2052 if (!LHSIsNull && !RHSIsNull && 2053 !Context.typesAreBlockCompatible(lpointee, rpointee)) { 2054 Diag(loc, diag::err_typecheck_comparison_of_distinct_blocks, 2055 lType.getAsString(), rType.getAsString(), 2056 lex->getSourceRange(), rex->getSourceRange()); 2057 } 2058 ImpCastExprToType(rex, lType); // promote the pointer to pointer 2059 return Context.IntTy; 2060 } 2061 // Allow block pointers to be compared with null pointer constants. 2062 if ((lType->isBlockPointerType() && rType->isPointerType()) || 2063 (lType->isPointerType() && rType->isBlockPointerType())) { 2064 if (!LHSIsNull && !RHSIsNull) { 2065 Diag(loc, diag::err_typecheck_comparison_of_distinct_blocks, 2066 lType.getAsString(), rType.getAsString(), 2067 lex->getSourceRange(), rex->getSourceRange()); 2068 } 2069 ImpCastExprToType(rex, lType); // promote the pointer to pointer 2070 return Context.IntTy; 2071 } 2072 2073 if ((lType->isObjCQualifiedIdType() || rType->isObjCQualifiedIdType())) { 2074 if (ObjCQualifiedIdTypesAreCompatible(lType, rType, true)) { 2075 ImpCastExprToType(rex, lType); 2076 return Context.IntTy; 2077 } 2078 } 2079 if ((lType->isPointerType() || lType->isObjCQualifiedIdType()) && 2080 rType->isIntegerType()) { 2081 if (!RHSIsNull) 2082 Diag(loc, diag::ext_typecheck_comparison_of_pointer_integer, 2083 lType.getAsString(), rType.getAsString(), 2084 lex->getSourceRange(), rex->getSourceRange()); 2085 ImpCastExprToType(rex, lType); // promote the integer to pointer 2086 return Context.IntTy; 2087 } 2088 if (lType->isIntegerType() && 2089 (rType->isPointerType() || rType->isObjCQualifiedIdType())) { 2090 if (!LHSIsNull) 2091 Diag(loc, diag::ext_typecheck_comparison_of_pointer_integer, 2092 lType.getAsString(), rType.getAsString(), 2093 lex->getSourceRange(), rex->getSourceRange()); 2094 ImpCastExprToType(lex, rType); // promote the integer to pointer 2095 return Context.IntTy; 2096 } 2097 // Handle block pointers. 2098 if (lType->isBlockPointerType() && rType->isIntegerType()) { 2099 if (!RHSIsNull) 2100 Diag(loc, diag::ext_typecheck_comparison_of_pointer_integer, 2101 lType.getAsString(), rType.getAsString(), 2102 lex->getSourceRange(), rex->getSourceRange()); 2103 ImpCastExprToType(rex, lType); // promote the integer to pointer 2104 return Context.IntTy; 2105 } 2106 if (lType->isIntegerType() && rType->isBlockPointerType()) { 2107 if (!LHSIsNull) 2108 Diag(loc, diag::ext_typecheck_comparison_of_pointer_integer, 2109 lType.getAsString(), rType.getAsString(), 2110 lex->getSourceRange(), rex->getSourceRange()); 2111 ImpCastExprToType(lex, rType); // promote the integer to pointer 2112 return Context.IntTy; 2113 } 2114 return InvalidOperands(loc, lex, rex); 2115} 2116 2117/// CheckVectorCompareOperands - vector comparisons are a clang extension that 2118/// operates on extended vector types. Instead of producing an IntTy result, 2119/// like a scalar comparison, a vector comparison produces a vector of integer 2120/// types. 2121QualType Sema::CheckVectorCompareOperands(Expr *&lex, Expr *&rex, 2122 SourceLocation loc, 2123 bool isRelational) { 2124 // Check to make sure we're operating on vectors of the same type and width, 2125 // Allowing one side to be a scalar of element type. 2126 QualType vType = CheckVectorOperands(loc, lex, rex); 2127 if (vType.isNull()) 2128 return vType; 2129 2130 QualType lType = lex->getType(); 2131 QualType rType = rex->getType(); 2132 2133 // For non-floating point types, check for self-comparisons of the form 2134 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 2135 // often indicate logic errors in the program. 2136 if (!lType->isFloatingType()) { 2137 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(lex->IgnoreParens())) 2138 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(rex->IgnoreParens())) 2139 if (DRL->getDecl() == DRR->getDecl()) 2140 Diag(loc, diag::warn_selfcomparison); 2141 } 2142 2143 // Check for comparisons of floating point operands using != and ==. 2144 if (!isRelational && lType->isFloatingType()) { 2145 assert (rType->isFloatingType()); 2146 CheckFloatComparison(loc,lex,rex); 2147 } 2148 2149 // Return the type for the comparison, which is the same as vector type for 2150 // integer vectors, or an integer type of identical size and number of 2151 // elements for floating point vectors. 2152 if (lType->isIntegerType()) 2153 return lType; 2154 2155 const VectorType *VTy = lType->getAsVectorType(); 2156 2157 // FIXME: need to deal with non-32b int / non-64b long long 2158 unsigned TypeSize = Context.getTypeSize(VTy->getElementType()); 2159 if (TypeSize == 32) { 2160 return Context.getExtVectorType(Context.IntTy, VTy->getNumElements()); 2161 } 2162 assert(TypeSize == 64 && "Unhandled vector element size in vector compare"); 2163 return Context.getExtVectorType(Context.LongLongTy, VTy->getNumElements()); 2164} 2165 2166inline QualType Sema::CheckBitwiseOperands( 2167 Expr *&lex, Expr *&rex, SourceLocation loc, bool isCompAssign) 2168{ 2169 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 2170 return CheckVectorOperands(loc, lex, rex); 2171 2172 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 2173 2174 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 2175 return compType; 2176 return InvalidOperands(loc, lex, rex); 2177} 2178 2179inline QualType Sema::CheckLogicalOperands( // C99 6.5.[13,14] 2180 Expr *&lex, Expr *&rex, SourceLocation loc) 2181{ 2182 UsualUnaryConversions(lex); 2183 UsualUnaryConversions(rex); 2184 2185 if (lex->getType()->isScalarType() && rex->getType()->isScalarType()) 2186 return Context.IntTy; 2187 return InvalidOperands(loc, lex, rex); 2188} 2189 2190inline QualType Sema::CheckAssignmentOperands( // C99 6.5.16.1 2191 Expr *lex, Expr *&rex, SourceLocation loc, QualType compoundType) 2192{ 2193 QualType lhsType = lex->getType(); 2194 QualType rhsType = compoundType.isNull() ? rex->getType() : compoundType; 2195 Expr::isModifiableLvalueResult mlval = lex->isModifiableLvalue(Context); 2196 2197 switch (mlval) { // C99 6.5.16p2 2198 case Expr::MLV_Valid: 2199 break; 2200 case Expr::MLV_ConstQualified: 2201 Diag(loc, diag::err_typecheck_assign_const, lex->getSourceRange()); 2202 return QualType(); 2203 case Expr::MLV_ArrayType: 2204 Diag(loc, diag::err_typecheck_array_not_modifiable_lvalue, 2205 lhsType.getAsString(), lex->getSourceRange()); 2206 return QualType(); 2207 case Expr::MLV_NotObjectType: 2208 Diag(loc, diag::err_typecheck_non_object_not_modifiable_lvalue, 2209 lhsType.getAsString(), lex->getSourceRange()); 2210 return QualType(); 2211 case Expr::MLV_InvalidExpression: 2212 Diag(loc, diag::err_typecheck_expression_not_modifiable_lvalue, 2213 lex->getSourceRange()); 2214 return QualType(); 2215 case Expr::MLV_IncompleteType: 2216 case Expr::MLV_IncompleteVoidType: 2217 Diag(loc, diag::err_typecheck_incomplete_type_not_modifiable_lvalue, 2218 lhsType.getAsString(), lex->getSourceRange()); 2219 return QualType(); 2220 case Expr::MLV_DuplicateVectorComponents: 2221 Diag(loc, diag::err_typecheck_duplicate_vector_components_not_mlvalue, 2222 lex->getSourceRange()); 2223 return QualType(); 2224 case Expr::MLV_NotBlockQualified: 2225 Diag(loc, diag::err_block_decl_ref_not_modifiable_lvalue, 2226 lex->getSourceRange()); 2227 return QualType(); 2228 } 2229 2230 AssignConvertType ConvTy; 2231 if (compoundType.isNull()) { 2232 // Simple assignment "x = y". 2233 ConvTy = CheckSingleAssignmentConstraints(lhsType, rex); 2234 2235 // If the RHS is a unary plus or minus, check to see if they = and + are 2236 // right next to each other. If so, the user may have typo'd "x =+ 4" 2237 // instead of "x += 4". 2238 Expr *RHSCheck = rex; 2239 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(RHSCheck)) 2240 RHSCheck = ICE->getSubExpr(); 2241 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(RHSCheck)) { 2242 if ((UO->getOpcode() == UnaryOperator::Plus || 2243 UO->getOpcode() == UnaryOperator::Minus) && 2244 loc.isFileID() && UO->getOperatorLoc().isFileID() && 2245 // Only if the two operators are exactly adjacent. 2246 loc.getFileLocWithOffset(1) == UO->getOperatorLoc()) 2247 Diag(loc, diag::warn_not_compound_assign, 2248 UO->getOpcode() == UnaryOperator::Plus ? "+" : "-", 2249 SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc())); 2250 } 2251 } else { 2252 // Compound assignment "x += y" 2253 ConvTy = CheckCompoundAssignmentConstraints(lhsType, rhsType); 2254 } 2255 2256 if (DiagnoseAssignmentResult(ConvTy, loc, lhsType, rhsType, 2257 rex, "assigning")) 2258 return QualType(); 2259 2260 // C99 6.5.16p3: The type of an assignment expression is the type of the 2261 // left operand unless the left operand has qualified type, in which case 2262 // it is the unqualified version of the type of the left operand. 2263 // C99 6.5.16.1p2: In simple assignment, the value of the right operand 2264 // is converted to the type of the assignment expression (above). 2265 // C++ 5.17p1: the type of the assignment expression is that of its left 2266 // oprdu. 2267 return lhsType.getUnqualifiedType(); 2268} 2269 2270inline QualType Sema::CheckCommaOperands( // C99 6.5.17 2271 Expr *&lex, Expr *&rex, SourceLocation loc) { 2272 2273 // Comma performs lvalue conversion (C99 6.3.2.1), but not unary conversions. 2274 DefaultFunctionArrayConversion(rex); 2275 return rex->getType(); 2276} 2277 2278/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine 2279/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions. 2280QualType Sema::CheckIncrementDecrementOperand(Expr *op, SourceLocation OpLoc) { 2281 QualType resType = op->getType(); 2282 assert(!resType.isNull() && "no type for increment/decrement expression"); 2283 2284 // C99 6.5.2.4p1: We allow complex as a GCC extension. 2285 if (const PointerType *pt = resType->getAsPointerType()) { 2286 if (pt->getPointeeType()->isVoidType()) { 2287 Diag(OpLoc, diag::ext_gnu_void_ptr, op->getSourceRange()); 2288 } else if (!pt->getPointeeType()->isObjectType()) { 2289 // C99 6.5.2.4p2, 6.5.6p2 2290 Diag(OpLoc, diag::err_typecheck_arithmetic_incomplete_type, 2291 resType.getAsString(), op->getSourceRange()); 2292 return QualType(); 2293 } 2294 } else if (!resType->isRealType()) { 2295 if (resType->isComplexType()) 2296 // C99 does not support ++/-- on complex types. 2297 Diag(OpLoc, diag::ext_integer_increment_complex, 2298 resType.getAsString(), op->getSourceRange()); 2299 else { 2300 Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement, 2301 resType.getAsString(), op->getSourceRange()); 2302 return QualType(); 2303 } 2304 } 2305 // At this point, we know we have a real, complex or pointer type. 2306 // Now make sure the operand is a modifiable lvalue. 2307 Expr::isModifiableLvalueResult mlval = op->isModifiableLvalue(Context); 2308 if (mlval != Expr::MLV_Valid) { 2309 // FIXME: emit a more precise diagnostic... 2310 Diag(OpLoc, diag::err_typecheck_invalid_lvalue_incr_decr, 2311 op->getSourceRange()); 2312 return QualType(); 2313 } 2314 return resType; 2315} 2316 2317/// getPrimaryDecl - Helper function for CheckAddressOfOperand(). 2318/// This routine allows us to typecheck complex/recursive expressions 2319/// where the declaration is needed for type checking. We only need to 2320/// handle cases when the expression references a function designator 2321/// or is an lvalue. Here are some examples: 2322/// - &(x) => x 2323/// - &*****f => f for f a function designator. 2324/// - &s.xx => s 2325/// - &s.zz[1].yy -> s, if zz is an array 2326/// - *(x + 1) -> x, if x is an array 2327/// - &"123"[2] -> 0 2328/// - & __real__ x -> x 2329static ValueDecl *getPrimaryDecl(Expr *E) { 2330 switch (E->getStmtClass()) { 2331 case Stmt::DeclRefExprClass: 2332 return cast<DeclRefExpr>(E)->getDecl(); 2333 case Stmt::MemberExprClass: 2334 // Fields cannot be declared with a 'register' storage class. 2335 // &X->f is always ok, even if X is declared register. 2336 if (cast<MemberExpr>(E)->isArrow()) 2337 return 0; 2338 return getPrimaryDecl(cast<MemberExpr>(E)->getBase()); 2339 case Stmt::ArraySubscriptExprClass: { 2340 // &X[4] and &4[X] refers to X if X is not a pointer. 2341 2342 ValueDecl *VD = getPrimaryDecl(cast<ArraySubscriptExpr>(E)->getBase()); 2343 if (!VD || VD->getType()->isPointerType()) 2344 return 0; 2345 else 2346 return VD; 2347 } 2348 case Stmt::UnaryOperatorClass: { 2349 UnaryOperator *UO = cast<UnaryOperator>(E); 2350 2351 switch(UO->getOpcode()) { 2352 case UnaryOperator::Deref: { 2353 // *(X + 1) refers to X if X is not a pointer. 2354 ValueDecl *VD = getPrimaryDecl(UO->getSubExpr()); 2355 if (!VD || VD->getType()->isPointerType()) 2356 return 0; 2357 return VD; 2358 } 2359 case UnaryOperator::Real: 2360 case UnaryOperator::Imag: 2361 case UnaryOperator::Extension: 2362 return getPrimaryDecl(UO->getSubExpr()); 2363 default: 2364 return 0; 2365 } 2366 } 2367 case Stmt::BinaryOperatorClass: { 2368 BinaryOperator *BO = cast<BinaryOperator>(E); 2369 2370 // Handle cases involving pointer arithmetic. The result of an 2371 // Assign or AddAssign is not an lvalue so they can be ignored. 2372 2373 // (x + n) or (n + x) => x 2374 if (BO->getOpcode() == BinaryOperator::Add) { 2375 if (BO->getLHS()->getType()->isPointerType()) { 2376 return getPrimaryDecl(BO->getLHS()); 2377 } else if (BO->getRHS()->getType()->isPointerType()) { 2378 return getPrimaryDecl(BO->getRHS()); 2379 } 2380 } 2381 2382 return 0; 2383 } 2384 case Stmt::ParenExprClass: 2385 return getPrimaryDecl(cast<ParenExpr>(E)->getSubExpr()); 2386 case Stmt::ImplicitCastExprClass: 2387 // &X[4] when X is an array, has an implicit cast from array to pointer. 2388 return getPrimaryDecl(cast<ImplicitCastExpr>(E)->getSubExpr()); 2389 default: 2390 return 0; 2391 } 2392} 2393 2394/// CheckAddressOfOperand - The operand of & must be either a function 2395/// designator or an lvalue designating an object. If it is an lvalue, the 2396/// object cannot be declared with storage class register or be a bit field. 2397/// Note: The usual conversions are *not* applied to the operand of the & 2398/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue. 2399QualType Sema::CheckAddressOfOperand(Expr *op, SourceLocation OpLoc) { 2400 if (getLangOptions().C99) { 2401 // Implement C99-only parts of addressof rules. 2402 if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(op)) { 2403 if (uOp->getOpcode() == UnaryOperator::Deref) 2404 // Per C99 6.5.3.2, the address of a deref always returns a valid result 2405 // (assuming the deref expression is valid). 2406 return uOp->getSubExpr()->getType(); 2407 } 2408 // Technically, there should be a check for array subscript 2409 // expressions here, but the result of one is always an lvalue anyway. 2410 } 2411 ValueDecl *dcl = getPrimaryDecl(op); 2412 Expr::isLvalueResult lval = op->isLvalue(Context); 2413 2414 if (lval != Expr::LV_Valid) { // C99 6.5.3.2p1 2415 if (!dcl || !isa<FunctionDecl>(dcl)) {// allow function designators 2416 // FIXME: emit more specific diag... 2417 Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof, 2418 op->getSourceRange()); 2419 return QualType(); 2420 } 2421 } else if (MemberExpr *MemExpr = dyn_cast<MemberExpr>(op)) { // C99 6.5.3.2p1 2422 if (MemExpr->getMemberDecl()->isBitField()) { 2423 Diag(OpLoc, diag::err_typecheck_address_of, 2424 std::string("bit-field"), op->getSourceRange()); 2425 return QualType(); 2426 } 2427 // Check for Apple extension for accessing vector components. 2428 } else if (isa<ArraySubscriptExpr>(op) && 2429 cast<ArraySubscriptExpr>(op)->getBase()->getType()->isVectorType()) { 2430 Diag(OpLoc, diag::err_typecheck_address_of, 2431 std::string("vector"), op->getSourceRange()); 2432 return QualType(); 2433 } else if (dcl) { // C99 6.5.3.2p1 2434 // We have an lvalue with a decl. Make sure the decl is not declared 2435 // with the register storage-class specifier. 2436 if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) { 2437 if (vd->getStorageClass() == VarDecl::Register) { 2438 Diag(OpLoc, diag::err_typecheck_address_of, 2439 std::string("register variable"), op->getSourceRange()); 2440 return QualType(); 2441 } 2442 } else 2443 assert(0 && "Unknown/unexpected decl type"); 2444 } 2445 2446 // If the operand has type "type", the result has type "pointer to type". 2447 return Context.getPointerType(op->getType()); 2448} 2449 2450QualType Sema::CheckIndirectionOperand(Expr *op, SourceLocation OpLoc) { 2451 UsualUnaryConversions(op); 2452 QualType qType = op->getType(); 2453 2454 if (const PointerType *PT = qType->getAsPointerType()) { 2455 // Note that per both C89 and C99, this is always legal, even 2456 // if ptype is an incomplete type or void. 2457 // It would be possible to warn about dereferencing a 2458 // void pointer, but it's completely well-defined, 2459 // and such a warning is unlikely to catch any mistakes. 2460 return PT->getPointeeType(); 2461 } 2462 Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer, 2463 qType.getAsString(), op->getSourceRange()); 2464 return QualType(); 2465} 2466 2467static inline BinaryOperator::Opcode ConvertTokenKindToBinaryOpcode( 2468 tok::TokenKind Kind) { 2469 BinaryOperator::Opcode Opc; 2470 switch (Kind) { 2471 default: assert(0 && "Unknown binop!"); 2472 case tok::star: Opc = BinaryOperator::Mul; break; 2473 case tok::slash: Opc = BinaryOperator::Div; break; 2474 case tok::percent: Opc = BinaryOperator::Rem; break; 2475 case tok::plus: Opc = BinaryOperator::Add; break; 2476 case tok::minus: Opc = BinaryOperator::Sub; break; 2477 case tok::lessless: Opc = BinaryOperator::Shl; break; 2478 case tok::greatergreater: Opc = BinaryOperator::Shr; break; 2479 case tok::lessequal: Opc = BinaryOperator::LE; break; 2480 case tok::less: Opc = BinaryOperator::LT; break; 2481 case tok::greaterequal: Opc = BinaryOperator::GE; break; 2482 case tok::greater: Opc = BinaryOperator::GT; break; 2483 case tok::exclaimequal: Opc = BinaryOperator::NE; break; 2484 case tok::equalequal: Opc = BinaryOperator::EQ; break; 2485 case tok::amp: Opc = BinaryOperator::And; break; 2486 case tok::caret: Opc = BinaryOperator::Xor; break; 2487 case tok::pipe: Opc = BinaryOperator::Or; break; 2488 case tok::ampamp: Opc = BinaryOperator::LAnd; break; 2489 case tok::pipepipe: Opc = BinaryOperator::LOr; break; 2490 case tok::equal: Opc = BinaryOperator::Assign; break; 2491 case tok::starequal: Opc = BinaryOperator::MulAssign; break; 2492 case tok::slashequal: Opc = BinaryOperator::DivAssign; break; 2493 case tok::percentequal: Opc = BinaryOperator::RemAssign; break; 2494 case tok::plusequal: Opc = BinaryOperator::AddAssign; break; 2495 case tok::minusequal: Opc = BinaryOperator::SubAssign; break; 2496 case tok::lesslessequal: Opc = BinaryOperator::ShlAssign; break; 2497 case tok::greatergreaterequal: Opc = BinaryOperator::ShrAssign; break; 2498 case tok::ampequal: Opc = BinaryOperator::AndAssign; break; 2499 case tok::caretequal: Opc = BinaryOperator::XorAssign; break; 2500 case tok::pipeequal: Opc = BinaryOperator::OrAssign; break; 2501 case tok::comma: Opc = BinaryOperator::Comma; break; 2502 } 2503 return Opc; 2504} 2505 2506static inline UnaryOperator::Opcode ConvertTokenKindToUnaryOpcode( 2507 tok::TokenKind Kind) { 2508 UnaryOperator::Opcode Opc; 2509 switch (Kind) { 2510 default: assert(0 && "Unknown unary op!"); 2511 case tok::plusplus: Opc = UnaryOperator::PreInc; break; 2512 case tok::minusminus: Opc = UnaryOperator::PreDec; break; 2513 case tok::amp: Opc = UnaryOperator::AddrOf; break; 2514 case tok::star: Opc = UnaryOperator::Deref; break; 2515 case tok::plus: Opc = UnaryOperator::Plus; break; 2516 case tok::minus: Opc = UnaryOperator::Minus; break; 2517 case tok::tilde: Opc = UnaryOperator::Not; break; 2518 case tok::exclaim: Opc = UnaryOperator::LNot; break; 2519 case tok::kw_sizeof: Opc = UnaryOperator::SizeOf; break; 2520 case tok::kw___alignof: Opc = UnaryOperator::AlignOf; break; 2521 case tok::kw___real: Opc = UnaryOperator::Real; break; 2522 case tok::kw___imag: Opc = UnaryOperator::Imag; break; 2523 case tok::kw___extension__: Opc = UnaryOperator::Extension; break; 2524 } 2525 return Opc; 2526} 2527 2528// Binary Operators. 'Tok' is the token for the operator. 2529Action::ExprResult Sema::ActOnBinOp(SourceLocation TokLoc, tok::TokenKind Kind, 2530 ExprTy *LHS, ExprTy *RHS) { 2531 BinaryOperator::Opcode Opc = ConvertTokenKindToBinaryOpcode(Kind); 2532 Expr *lhs = (Expr *)LHS, *rhs = (Expr*)RHS; 2533 2534 assert((lhs != 0) && "ActOnBinOp(): missing left expression"); 2535 assert((rhs != 0) && "ActOnBinOp(): missing right expression"); 2536 2537 QualType ResultTy; // Result type of the binary operator. 2538 QualType CompTy; // Computation type for compound assignments (e.g. '+=') 2539 2540 switch (Opc) { 2541 default: 2542 assert(0 && "Unknown binary expr!"); 2543 case BinaryOperator::Assign: 2544 ResultTy = CheckAssignmentOperands(lhs, rhs, TokLoc, QualType()); 2545 break; 2546 case BinaryOperator::Mul: 2547 case BinaryOperator::Div: 2548 ResultTy = CheckMultiplyDivideOperands(lhs, rhs, TokLoc); 2549 break; 2550 case BinaryOperator::Rem: 2551 ResultTy = CheckRemainderOperands(lhs, rhs, TokLoc); 2552 break; 2553 case BinaryOperator::Add: 2554 ResultTy = CheckAdditionOperands(lhs, rhs, TokLoc); 2555 break; 2556 case BinaryOperator::Sub: 2557 ResultTy = CheckSubtractionOperands(lhs, rhs, TokLoc); 2558 break; 2559 case BinaryOperator::Shl: 2560 case BinaryOperator::Shr: 2561 ResultTy = CheckShiftOperands(lhs, rhs, TokLoc); 2562 break; 2563 case BinaryOperator::LE: 2564 case BinaryOperator::LT: 2565 case BinaryOperator::GE: 2566 case BinaryOperator::GT: 2567 ResultTy = CheckCompareOperands(lhs, rhs, TokLoc, true); 2568 break; 2569 case BinaryOperator::EQ: 2570 case BinaryOperator::NE: 2571 ResultTy = CheckCompareOperands(lhs, rhs, TokLoc, false); 2572 break; 2573 case BinaryOperator::And: 2574 case BinaryOperator::Xor: 2575 case BinaryOperator::Or: 2576 ResultTy = CheckBitwiseOperands(lhs, rhs, TokLoc); 2577 break; 2578 case BinaryOperator::LAnd: 2579 case BinaryOperator::LOr: 2580 ResultTy = CheckLogicalOperands(lhs, rhs, TokLoc); 2581 break; 2582 case BinaryOperator::MulAssign: 2583 case BinaryOperator::DivAssign: 2584 CompTy = CheckMultiplyDivideOperands(lhs, rhs, TokLoc, true); 2585 if (!CompTy.isNull()) 2586 ResultTy = CheckAssignmentOperands(lhs, rhs, TokLoc, CompTy); 2587 break; 2588 case BinaryOperator::RemAssign: 2589 CompTy = CheckRemainderOperands(lhs, rhs, TokLoc, true); 2590 if (!CompTy.isNull()) 2591 ResultTy = CheckAssignmentOperands(lhs, rhs, TokLoc, CompTy); 2592 break; 2593 case BinaryOperator::AddAssign: 2594 CompTy = CheckAdditionOperands(lhs, rhs, TokLoc, true); 2595 if (!CompTy.isNull()) 2596 ResultTy = CheckAssignmentOperands(lhs, rhs, TokLoc, CompTy); 2597 break; 2598 case BinaryOperator::SubAssign: 2599 CompTy = CheckSubtractionOperands(lhs, rhs, TokLoc, true); 2600 if (!CompTy.isNull()) 2601 ResultTy = CheckAssignmentOperands(lhs, rhs, TokLoc, CompTy); 2602 break; 2603 case BinaryOperator::ShlAssign: 2604 case BinaryOperator::ShrAssign: 2605 CompTy = CheckShiftOperands(lhs, rhs, TokLoc, true); 2606 if (!CompTy.isNull()) 2607 ResultTy = CheckAssignmentOperands(lhs, rhs, TokLoc, CompTy); 2608 break; 2609 case BinaryOperator::AndAssign: 2610 case BinaryOperator::XorAssign: 2611 case BinaryOperator::OrAssign: 2612 CompTy = CheckBitwiseOperands(lhs, rhs, TokLoc, true); 2613 if (!CompTy.isNull()) 2614 ResultTy = CheckAssignmentOperands(lhs, rhs, TokLoc, CompTy); 2615 break; 2616 case BinaryOperator::Comma: 2617 ResultTy = CheckCommaOperands(lhs, rhs, TokLoc); 2618 break; 2619 } 2620 if (ResultTy.isNull()) 2621 return true; 2622 if (CompTy.isNull()) 2623 return new BinaryOperator(lhs, rhs, Opc, ResultTy, TokLoc); 2624 else 2625 return new CompoundAssignOperator(lhs, rhs, Opc, ResultTy, CompTy, TokLoc); 2626} 2627 2628// Unary Operators. 'Tok' is the token for the operator. 2629Action::ExprResult Sema::ActOnUnaryOp(SourceLocation OpLoc, tok::TokenKind Op, 2630 ExprTy *input) { 2631 Expr *Input = (Expr*)input; 2632 UnaryOperator::Opcode Opc = ConvertTokenKindToUnaryOpcode(Op); 2633 QualType resultType; 2634 switch (Opc) { 2635 default: 2636 assert(0 && "Unimplemented unary expr!"); 2637 case UnaryOperator::PreInc: 2638 case UnaryOperator::PreDec: 2639 resultType = CheckIncrementDecrementOperand(Input, OpLoc); 2640 break; 2641 case UnaryOperator::AddrOf: 2642 resultType = CheckAddressOfOperand(Input, OpLoc); 2643 break; 2644 case UnaryOperator::Deref: 2645 DefaultFunctionArrayConversion(Input); 2646 resultType = CheckIndirectionOperand(Input, OpLoc); 2647 break; 2648 case UnaryOperator::Plus: 2649 case UnaryOperator::Minus: 2650 UsualUnaryConversions(Input); 2651 resultType = Input->getType(); 2652 if (!resultType->isArithmeticType()) // C99 6.5.3.3p1 2653 return Diag(OpLoc, diag::err_typecheck_unary_expr, 2654 resultType.getAsString()); 2655 break; 2656 case UnaryOperator::Not: // bitwise complement 2657 UsualUnaryConversions(Input); 2658 resultType = Input->getType(); 2659 // C99 6.5.3.3p1. We allow complex int and float as a GCC extension. 2660 if (resultType->isComplexType() || resultType->isComplexIntegerType()) 2661 // C99 does not support '~' for complex conjugation. 2662 Diag(OpLoc, diag::ext_integer_complement_complex, 2663 resultType.getAsString(), Input->getSourceRange()); 2664 else if (!resultType->isIntegerType()) 2665 return Diag(OpLoc, diag::err_typecheck_unary_expr, 2666 resultType.getAsString(), Input->getSourceRange()); 2667 break; 2668 case UnaryOperator::LNot: // logical negation 2669 // Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5). 2670 DefaultFunctionArrayConversion(Input); 2671 resultType = Input->getType(); 2672 if (!resultType->isScalarType()) // C99 6.5.3.3p1 2673 return Diag(OpLoc, diag::err_typecheck_unary_expr, 2674 resultType.getAsString()); 2675 // LNot always has type int. C99 6.5.3.3p5. 2676 resultType = Context.IntTy; 2677 break; 2678 case UnaryOperator::SizeOf: 2679 resultType = CheckSizeOfAlignOfOperand(Input->getType(), OpLoc, 2680 Input->getSourceRange(), true); 2681 break; 2682 case UnaryOperator::AlignOf: 2683 resultType = CheckSizeOfAlignOfOperand(Input->getType(), OpLoc, 2684 Input->getSourceRange(), false); 2685 break; 2686 case UnaryOperator::Real: 2687 case UnaryOperator::Imag: 2688 resultType = CheckRealImagOperand(Input, OpLoc); 2689 break; 2690 case UnaryOperator::Extension: 2691 resultType = Input->getType(); 2692 break; 2693 } 2694 if (resultType.isNull()) 2695 return true; 2696 return new UnaryOperator(Input, Opc, resultType, OpLoc); 2697} 2698 2699/// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo". 2700Sema::ExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, 2701 SourceLocation LabLoc, 2702 IdentifierInfo *LabelII) { 2703 // Look up the record for this label identifier. 2704 LabelStmt *&LabelDecl = LabelMap[LabelII]; 2705 2706 // If we haven't seen this label yet, create a forward reference. It 2707 // will be validated and/or cleaned up in ActOnFinishFunctionBody. 2708 if (LabelDecl == 0) 2709 LabelDecl = new LabelStmt(LabLoc, LabelII, 0); 2710 2711 // Create the AST node. The address of a label always has type 'void*'. 2712 return new AddrLabelExpr(OpLoc, LabLoc, LabelDecl, 2713 Context.getPointerType(Context.VoidTy)); 2714} 2715 2716Sema::ExprResult Sema::ActOnStmtExpr(SourceLocation LPLoc, StmtTy *substmt, 2717 SourceLocation RPLoc) { // "({..})" 2718 Stmt *SubStmt = static_cast<Stmt*>(substmt); 2719 assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!"); 2720 CompoundStmt *Compound = cast<CompoundStmt>(SubStmt); 2721 2722 // FIXME: there are a variety of strange constraints to enforce here, for 2723 // example, it is not possible to goto into a stmt expression apparently. 2724 // More semantic analysis is needed. 2725 2726 // FIXME: the last statement in the compount stmt has its value used. We 2727 // should not warn about it being unused. 2728 2729 // If there are sub stmts in the compound stmt, take the type of the last one 2730 // as the type of the stmtexpr. 2731 QualType Ty = Context.VoidTy; 2732 2733 if (!Compound->body_empty()) { 2734 Stmt *LastStmt = Compound->body_back(); 2735 // If LastStmt is a label, skip down through into the body. 2736 while (LabelStmt *Label = dyn_cast<LabelStmt>(LastStmt)) 2737 LastStmt = Label->getSubStmt(); 2738 2739 if (Expr *LastExpr = dyn_cast<Expr>(LastStmt)) 2740 Ty = LastExpr->getType(); 2741 } 2742 2743 return new StmtExpr(Compound, Ty, LPLoc, RPLoc); 2744} 2745 2746Sema::ExprResult Sema::ActOnBuiltinOffsetOf(SourceLocation BuiltinLoc, 2747 SourceLocation TypeLoc, 2748 TypeTy *argty, 2749 OffsetOfComponent *CompPtr, 2750 unsigned NumComponents, 2751 SourceLocation RPLoc) { 2752 QualType ArgTy = QualType::getFromOpaquePtr(argty); 2753 assert(!ArgTy.isNull() && "Missing type argument!"); 2754 2755 // We must have at least one component that refers to the type, and the first 2756 // one is known to be a field designator. Verify that the ArgTy represents 2757 // a struct/union/class. 2758 if (!ArgTy->isRecordType()) 2759 return Diag(TypeLoc, diag::err_offsetof_record_type,ArgTy.getAsString()); 2760 2761 // Otherwise, create a compound literal expression as the base, and 2762 // iteratively process the offsetof designators. 2763 Expr *Res = new CompoundLiteralExpr(SourceLocation(), ArgTy, 0, false); 2764 2765 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 2766 // GCC extension, diagnose them. 2767 if (NumComponents != 1) 2768 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator, 2769 SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd)); 2770 2771 for (unsigned i = 0; i != NumComponents; ++i) { 2772 const OffsetOfComponent &OC = CompPtr[i]; 2773 if (OC.isBrackets) { 2774 // Offset of an array sub-field. TODO: Should we allow vector elements? 2775 const ArrayType *AT = Context.getAsArrayType(Res->getType()); 2776 if (!AT) { 2777 delete Res; 2778 return Diag(OC.LocEnd, diag::err_offsetof_array_type, 2779 Res->getType().getAsString()); 2780 } 2781 2782 // FIXME: C++: Verify that operator[] isn't overloaded. 2783 2784 // C99 6.5.2.1p1 2785 Expr *Idx = static_cast<Expr*>(OC.U.E); 2786 if (!Idx->getType()->isIntegerType()) 2787 return Diag(Idx->getLocStart(), diag::err_typecheck_subscript, 2788 Idx->getSourceRange()); 2789 2790 Res = new ArraySubscriptExpr(Res, Idx, AT->getElementType(), OC.LocEnd); 2791 continue; 2792 } 2793 2794 const RecordType *RC = Res->getType()->getAsRecordType(); 2795 if (!RC) { 2796 delete Res; 2797 return Diag(OC.LocEnd, diag::err_offsetof_record_type, 2798 Res->getType().getAsString()); 2799 } 2800 2801 // Get the decl corresponding to this. 2802 RecordDecl *RD = RC->getDecl(); 2803 FieldDecl *MemberDecl = RD->getMember(OC.U.IdentInfo); 2804 if (!MemberDecl) 2805 return Diag(BuiltinLoc, diag::err_typecheck_no_member, 2806 OC.U.IdentInfo->getName(), 2807 SourceRange(OC.LocStart, OC.LocEnd)); 2808 2809 // FIXME: C++: Verify that MemberDecl isn't a static field. 2810 // FIXME: Verify that MemberDecl isn't a bitfield. 2811 // MemberDecl->getType() doesn't get the right qualifiers, but it doesn't 2812 // matter here. 2813 Res = new MemberExpr(Res, false, MemberDecl, OC.LocEnd, MemberDecl->getType()); 2814 } 2815 2816 return new UnaryOperator(Res, UnaryOperator::OffsetOf, Context.getSizeType(), 2817 BuiltinLoc); 2818} 2819 2820 2821Sema::ExprResult Sema::ActOnTypesCompatibleExpr(SourceLocation BuiltinLoc, 2822 TypeTy *arg1, TypeTy *arg2, 2823 SourceLocation RPLoc) { 2824 QualType argT1 = QualType::getFromOpaquePtr(arg1); 2825 QualType argT2 = QualType::getFromOpaquePtr(arg2); 2826 2827 assert((!argT1.isNull() && !argT2.isNull()) && "Missing type argument(s)"); 2828 2829 return new TypesCompatibleExpr(Context.IntTy, BuiltinLoc, argT1, argT2,RPLoc); 2830} 2831 2832Sema::ExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc, ExprTy *cond, 2833 ExprTy *expr1, ExprTy *expr2, 2834 SourceLocation RPLoc) { 2835 Expr *CondExpr = static_cast<Expr*>(cond); 2836 Expr *LHSExpr = static_cast<Expr*>(expr1); 2837 Expr *RHSExpr = static_cast<Expr*>(expr2); 2838 2839 assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)"); 2840 2841 // The conditional expression is required to be a constant expression. 2842 llvm::APSInt condEval(32); 2843 SourceLocation ExpLoc; 2844 if (!CondExpr->isIntegerConstantExpr(condEval, Context, &ExpLoc)) 2845 return Diag(ExpLoc, diag::err_typecheck_choose_expr_requires_constant, 2846 CondExpr->getSourceRange()); 2847 2848 // If the condition is > zero, then the AST type is the same as the LSHExpr. 2849 QualType resType = condEval.getZExtValue() ? LHSExpr->getType() : 2850 RHSExpr->getType(); 2851 return new ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, resType, RPLoc); 2852} 2853 2854//===----------------------------------------------------------------------===// 2855// Clang Extensions. 2856//===----------------------------------------------------------------------===// 2857 2858/// ActOnBlockStart - This callback is invoked when a block literal is started. 2859void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *BlockScope, 2860 Declarator &ParamInfo) { 2861 // Analyze block parameters. 2862 BlockSemaInfo *BSI = new BlockSemaInfo(); 2863 2864 // Add BSI to CurBlock. 2865 BSI->PrevBlockInfo = CurBlock; 2866 CurBlock = BSI; 2867 2868 BSI->ReturnType = 0; 2869 BSI->TheScope = BlockScope; 2870 2871 // Analyze arguments to block. 2872 assert(ParamInfo.getTypeObject(0).Kind == DeclaratorChunk::Function && 2873 "Not a function declarator!"); 2874 DeclaratorChunk::FunctionTypeInfo &FTI = ParamInfo.getTypeObject(0).Fun; 2875 2876 BSI->hasPrototype = FTI.hasPrototype; 2877 BSI->isVariadic = true; 2878 2879 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs function that takes 2880 // no arguments, not a function that takes a single void argument. 2881 if (FTI.hasPrototype && 2882 FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2883 (!((ParmVarDecl *)FTI.ArgInfo[0].Param)->getType().getCVRQualifiers() && 2884 ((ParmVarDecl *)FTI.ArgInfo[0].Param)->getType()->isVoidType())) { 2885 // empty arg list, don't push any params. 2886 BSI->isVariadic = false; 2887 } else if (FTI.hasPrototype) { 2888 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 2889 BSI->Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 2890 BSI->isVariadic = FTI.isVariadic; 2891 } 2892} 2893 2894/// ActOnBlockError - If there is an error parsing a block, this callback 2895/// is invoked to pop the information about the block from the action impl. 2896void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) { 2897 // Ensure that CurBlock is deleted. 2898 llvm::OwningPtr<BlockSemaInfo> CC(CurBlock); 2899 2900 // Pop off CurBlock, handle nested blocks. 2901 CurBlock = CurBlock->PrevBlockInfo; 2902 2903 // FIXME: Delete the ParmVarDecl objects as well??? 2904 2905} 2906 2907/// ActOnBlockStmtExpr - This is called when the body of a block statement 2908/// literal was successfully completed. ^(int x){...} 2909Sema::ExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc, StmtTy *body, 2910 Scope *CurScope) { 2911 // Ensure that CurBlock is deleted. 2912 llvm::OwningPtr<BlockSemaInfo> BSI(CurBlock); 2913 llvm::OwningPtr<CompoundStmt> Body(static_cast<CompoundStmt*>(body)); 2914 2915 // Pop off CurBlock, handle nested blocks. 2916 CurBlock = CurBlock->PrevBlockInfo; 2917 2918 QualType RetTy = Context.VoidTy; 2919 if (BSI->ReturnType) 2920 RetTy = QualType(BSI->ReturnType, 0); 2921 2922 llvm::SmallVector<QualType, 8> ArgTypes; 2923 for (unsigned i = 0, e = BSI->Params.size(); i != e; ++i) 2924 ArgTypes.push_back(BSI->Params[i]->getType()); 2925 2926 QualType BlockTy; 2927 if (!BSI->hasPrototype) 2928 BlockTy = Context.getFunctionTypeNoProto(RetTy); 2929 else 2930 BlockTy = Context.getFunctionType(RetTy, &ArgTypes[0], ArgTypes.size(), 2931 BSI->isVariadic); 2932 2933 BlockTy = Context.getBlockPointerType(BlockTy); 2934 return new BlockExpr(CaretLoc, BlockTy, &BSI->Params[0], BSI->Params.size(), 2935 Body.take()); 2936} 2937 2938/// ExprsMatchFnType - return true if the Exprs in array Args have 2939/// QualTypes that match the QualTypes of the arguments of the FnType. 2940/// The number of arguments has already been validated to match the number of 2941/// arguments in FnType. 2942static bool ExprsMatchFnType(Expr **Args, const FunctionTypeProto *FnType, 2943 ASTContext &Context) { 2944 unsigned NumParams = FnType->getNumArgs(); 2945 for (unsigned i = 0; i != NumParams; ++i) { 2946 QualType ExprTy = Context.getCanonicalType(Args[i]->getType()); 2947 QualType ParmTy = Context.getCanonicalType(FnType->getArgType(i)); 2948 2949 if (ExprTy.getUnqualifiedType() != ParmTy.getUnqualifiedType()) 2950 return false; 2951 } 2952 return true; 2953} 2954 2955Sema::ExprResult Sema::ActOnOverloadExpr(ExprTy **args, unsigned NumArgs, 2956 SourceLocation *CommaLocs, 2957 SourceLocation BuiltinLoc, 2958 SourceLocation RParenLoc) { 2959 // __builtin_overload requires at least 2 arguments 2960 if (NumArgs < 2) 2961 return Diag(RParenLoc, diag::err_typecheck_call_too_few_args, 2962 SourceRange(BuiltinLoc, RParenLoc)); 2963 2964 // The first argument is required to be a constant expression. It tells us 2965 // the number of arguments to pass to each of the functions to be overloaded. 2966 Expr **Args = reinterpret_cast<Expr**>(args); 2967 Expr *NParamsExpr = Args[0]; 2968 llvm::APSInt constEval(32); 2969 SourceLocation ExpLoc; 2970 if (!NParamsExpr->isIntegerConstantExpr(constEval, Context, &ExpLoc)) 2971 return Diag(ExpLoc, diag::err_overload_expr_requires_non_zero_constant, 2972 NParamsExpr->getSourceRange()); 2973 2974 // Verify that the number of parameters is > 0 2975 unsigned NumParams = constEval.getZExtValue(); 2976 if (NumParams == 0) 2977 return Diag(ExpLoc, diag::err_overload_expr_requires_non_zero_constant, 2978 NParamsExpr->getSourceRange()); 2979 // Verify that we have at least 1 + NumParams arguments to the builtin. 2980 if ((NumParams + 1) > NumArgs) 2981 return Diag(RParenLoc, diag::err_typecheck_call_too_few_args, 2982 SourceRange(BuiltinLoc, RParenLoc)); 2983 2984 // Figure out the return type, by matching the args to one of the functions 2985 // listed after the parameters. 2986 OverloadExpr *OE = 0; 2987 for (unsigned i = NumParams + 1; i < NumArgs; ++i) { 2988 // UsualUnaryConversions will convert the function DeclRefExpr into a 2989 // pointer to function. 2990 Expr *Fn = UsualUnaryConversions(Args[i]); 2991 const FunctionTypeProto *FnType = 0; 2992 if (const PointerType *PT = Fn->getType()->getAsPointerType()) 2993 FnType = PT->getPointeeType()->getAsFunctionTypeProto(); 2994 2995 // The Expr type must be FunctionTypeProto, since FunctionTypeProto has no 2996 // parameters, and the number of parameters must match the value passed to 2997 // the builtin. 2998 if (!FnType || (FnType->getNumArgs() != NumParams)) 2999 return Diag(Fn->getExprLoc(), diag::err_overload_incorrect_fntype, 3000 Fn->getSourceRange()); 3001 3002 // Scan the parameter list for the FunctionType, checking the QualType of 3003 // each parameter against the QualTypes of the arguments to the builtin. 3004 // If they match, return a new OverloadExpr. 3005 if (ExprsMatchFnType(Args+1, FnType, Context)) { 3006 if (OE) 3007 return Diag(Fn->getExprLoc(), diag::err_overload_multiple_match, 3008 OE->getFn()->getSourceRange()); 3009 // Remember our match, and continue processing the remaining arguments 3010 // to catch any errors. 3011 OE = new OverloadExpr(Args, NumArgs, i, FnType->getResultType(), 3012 BuiltinLoc, RParenLoc); 3013 } 3014 } 3015 // Return the newly created OverloadExpr node, if we succeded in matching 3016 // exactly one of the candidate functions. 3017 if (OE) 3018 return OE; 3019 3020 // If we didn't find a matching function Expr in the __builtin_overload list 3021 // the return an error. 3022 std::string typeNames; 3023 for (unsigned i = 0; i != NumParams; ++i) { 3024 if (i != 0) typeNames += ", "; 3025 typeNames += Args[i+1]->getType().getAsString(); 3026 } 3027 3028 return Diag(BuiltinLoc, diag::err_overload_no_match, typeNames, 3029 SourceRange(BuiltinLoc, RParenLoc)); 3030} 3031 3032Sema::ExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, 3033 ExprTy *expr, TypeTy *type, 3034 SourceLocation RPLoc) { 3035 Expr *E = static_cast<Expr*>(expr); 3036 QualType T = QualType::getFromOpaquePtr(type); 3037 3038 InitBuiltinVaListType(); 3039 3040 // Get the va_list type 3041 QualType VaListType = Context.getBuiltinVaListType(); 3042 // Deal with implicit array decay; for example, on x86-64, 3043 // va_list is an array, but it's supposed to decay to 3044 // a pointer for va_arg. 3045 if (VaListType->isArrayType()) 3046 VaListType = Context.getArrayDecayedType(VaListType); 3047 // Make sure the input expression also decays appropriately. 3048 UsualUnaryConversions(E); 3049 3050 if (CheckAssignmentConstraints(VaListType, E->getType()) != Compatible) 3051 return Diag(E->getLocStart(), 3052 diag::err_first_argument_to_va_arg_not_of_type_va_list, 3053 E->getType().getAsString(), 3054 E->getSourceRange()); 3055 3056 // FIXME: Warn if a non-POD type is passed in. 3057 3058 return new VAArgExpr(BuiltinLoc, E, T, RPLoc); 3059} 3060 3061bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy, 3062 SourceLocation Loc, 3063 QualType DstType, QualType SrcType, 3064 Expr *SrcExpr, const char *Flavor) { 3065 // Decode the result (notice that AST's are still created for extensions). 3066 bool isInvalid = false; 3067 unsigned DiagKind; 3068 switch (ConvTy) { 3069 default: assert(0 && "Unknown conversion type"); 3070 case Compatible: return false; 3071 case PointerToInt: 3072 DiagKind = diag::ext_typecheck_convert_pointer_int; 3073 break; 3074 case IntToPointer: 3075 DiagKind = diag::ext_typecheck_convert_int_pointer; 3076 break; 3077 case IncompatiblePointer: 3078 DiagKind = diag::ext_typecheck_convert_incompatible_pointer; 3079 break; 3080 case FunctionVoidPointer: 3081 DiagKind = diag::ext_typecheck_convert_pointer_void_func; 3082 break; 3083 case CompatiblePointerDiscardsQualifiers: 3084 // If the qualifiers lost were because we were applying the 3085 // (deprecated) C++ conversion from a string literal to a char* 3086 // (or wchar_t*), then there was no error (C++ 4.2p2). FIXME: 3087 // Ideally, this check would be performed in 3088 // CheckPointerTypesForAssignment. However, that would require a 3089 // bit of refactoring (so that the second argument is an 3090 // expression, rather than a type), which should be done as part 3091 // of a larger effort to fix CheckPointerTypesForAssignment for 3092 // C++ semantics. 3093 if (getLangOptions().CPlusPlus && 3094 IsStringLiteralToNonConstPointerConversion(SrcExpr, DstType)) 3095 return false; 3096 DiagKind = diag::ext_typecheck_convert_discards_qualifiers; 3097 break; 3098 case IntToBlockPointer: 3099 DiagKind = diag::err_int_to_block_pointer; 3100 break; 3101 case IncompatibleBlockPointer: 3102 DiagKind = diag::ext_typecheck_convert_incompatible_block_pointer; 3103 break; 3104 case BlockVoidPointer: 3105 DiagKind = diag::ext_typecheck_convert_pointer_void_block; 3106 break; 3107 case Incompatible: 3108 DiagKind = diag::err_typecheck_convert_incompatible; 3109 isInvalid = true; 3110 break; 3111 } 3112 3113 Diag(Loc, DiagKind, DstType.getAsString(), SrcType.getAsString(), Flavor, 3114 SrcExpr->getSourceRange()); 3115 return isInvalid; 3116} 3117