SemaExpr.cpp revision a982c71ef2d7b2307171784eb278330a349fa222
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 IntegerBuffer.resize(Tok.getLength()); 522 const char *ThisTokBegin = &IntegerBuffer[0]; 523 524 // Get the spelling of the token, which eliminates trigraphs, etc. 525 unsigned ActualLength = PP.getSpelling(Tok, ThisTokBegin); 526 NumericLiteralParser Literal(ThisTokBegin, ThisTokBegin+ActualLength, 527 Tok.getLocation(), PP); 528 if (Literal.hadError) 529 return ExprResult(true); 530 531 Expr *Res; 532 533 if (Literal.isFloatingLiteral()) { 534 QualType Ty; 535 if (Literal.isFloat) 536 Ty = Context.FloatTy; 537 else if (!Literal.isLong) 538 Ty = Context.DoubleTy; 539 else 540 Ty = Context.LongDoubleTy; 541 542 const llvm::fltSemantics &Format = Context.getFloatTypeSemantics(Ty); 543 544 // isExact will be set by GetFloatValue(). 545 bool isExact = false; 546 Res = new FloatingLiteral(Literal.GetFloatValue(Format, &isExact), &isExact, 547 Ty, Tok.getLocation()); 548 549 } else if (!Literal.isIntegerLiteral()) { 550 return ExprResult(true); 551 } else { 552 QualType Ty; 553 554 // long long is a C99 feature. 555 if (!getLangOptions().C99 && !getLangOptions().CPlusPlus0x && 556 Literal.isLongLong) 557 Diag(Tok.getLocation(), diag::ext_longlong); 558 559 // Get the value in the widest-possible width. 560 llvm::APInt ResultVal(Context.Target.getIntMaxTWidth(), 0); 561 562 if (Literal.GetIntegerValue(ResultVal)) { 563 // If this value didn't fit into uintmax_t, warn and force to ull. 564 Diag(Tok.getLocation(), diag::warn_integer_too_large); 565 Ty = Context.UnsignedLongLongTy; 566 assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() && 567 "long long is not intmax_t?"); 568 } else { 569 // If this value fits into a ULL, try to figure out what else it fits into 570 // according to the rules of C99 6.4.4.1p5. 571 572 // Octal, Hexadecimal, and integers with a U suffix are allowed to 573 // be an unsigned int. 574 bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10; 575 576 // Check from smallest to largest, picking the smallest type we can. 577 unsigned Width = 0; 578 if (!Literal.isLong && !Literal.isLongLong) { 579 // Are int/unsigned possibilities? 580 unsigned IntSize = Context.Target.getIntWidth(); 581 582 // Does it fit in a unsigned int? 583 if (ResultVal.isIntN(IntSize)) { 584 // Does it fit in a signed int? 585 if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0) 586 Ty = Context.IntTy; 587 else if (AllowUnsigned) 588 Ty = Context.UnsignedIntTy; 589 Width = IntSize; 590 } 591 } 592 593 // Are long/unsigned long possibilities? 594 if (Ty.isNull() && !Literal.isLongLong) { 595 unsigned LongSize = Context.Target.getLongWidth(); 596 597 // Does it fit in a unsigned long? 598 if (ResultVal.isIntN(LongSize)) { 599 // Does it fit in a signed long? 600 if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0) 601 Ty = Context.LongTy; 602 else if (AllowUnsigned) 603 Ty = Context.UnsignedLongTy; 604 Width = LongSize; 605 } 606 } 607 608 // Finally, check long long if needed. 609 if (Ty.isNull()) { 610 unsigned LongLongSize = Context.Target.getLongLongWidth(); 611 612 // Does it fit in a unsigned long long? 613 if (ResultVal.isIntN(LongLongSize)) { 614 // Does it fit in a signed long long? 615 if (!Literal.isUnsigned && ResultVal[LongLongSize-1] == 0) 616 Ty = Context.LongLongTy; 617 else if (AllowUnsigned) 618 Ty = Context.UnsignedLongLongTy; 619 Width = LongLongSize; 620 } 621 } 622 623 // If we still couldn't decide a type, we probably have something that 624 // does not fit in a signed long long, but has no U suffix. 625 if (Ty.isNull()) { 626 Diag(Tok.getLocation(), diag::warn_integer_too_large_for_signed); 627 Ty = Context.UnsignedLongLongTy; 628 Width = Context.Target.getLongLongWidth(); 629 } 630 631 if (ResultVal.getBitWidth() != Width) 632 ResultVal.trunc(Width); 633 } 634 635 Res = new IntegerLiteral(ResultVal, Ty, Tok.getLocation()); 636 } 637 638 // If this is an imaginary literal, create the ImaginaryLiteral wrapper. 639 if (Literal.isImaginary) 640 Res = new ImaginaryLiteral(Res, Context.getComplexType(Res->getType())); 641 642 return Res; 643} 644 645Action::ExprResult Sema::ActOnParenExpr(SourceLocation L, SourceLocation R, 646 ExprTy *Val) { 647 Expr *E = (Expr *)Val; 648 assert((E != 0) && "ActOnParenExpr() missing expr"); 649 return new ParenExpr(L, R, E); 650} 651 652/// The UsualUnaryConversions() function is *not* called by this routine. 653/// See C99 6.3.2.1p[2-4] for more details. 654QualType Sema::CheckSizeOfAlignOfOperand(QualType exprType, 655 SourceLocation OpLoc, 656 const SourceRange &ExprRange, 657 bool isSizeof) { 658 // C99 6.5.3.4p1: 659 if (isa<FunctionType>(exprType) && isSizeof) 660 // alignof(function) is allowed. 661 Diag(OpLoc, diag::ext_sizeof_function_type, ExprRange); 662 else if (exprType->isVoidType()) 663 Diag(OpLoc, diag::ext_sizeof_void_type, isSizeof ? "sizeof" : "__alignof", 664 ExprRange); 665 else if (exprType->isIncompleteType()) { 666 Diag(OpLoc, isSizeof ? diag::err_sizeof_incomplete_type : 667 diag::err_alignof_incomplete_type, 668 exprType.getAsString(), ExprRange); 669 return QualType(); // error 670 } 671 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t. 672 return Context.getSizeType(); 673} 674 675Action::ExprResult Sema:: 676ActOnSizeOfAlignOfTypeExpr(SourceLocation OpLoc, bool isSizeof, 677 SourceLocation LPLoc, TypeTy *Ty, 678 SourceLocation RPLoc) { 679 // If error parsing type, ignore. 680 if (Ty == 0) return true; 681 682 // Verify that this is a valid expression. 683 QualType ArgTy = QualType::getFromOpaquePtr(Ty); 684 685 QualType resultType = 686 CheckSizeOfAlignOfOperand(ArgTy, OpLoc, SourceRange(LPLoc, RPLoc),isSizeof); 687 688 if (resultType.isNull()) 689 return true; 690 return new SizeOfAlignOfTypeExpr(isSizeof, ArgTy, resultType, OpLoc, RPLoc); 691} 692 693QualType Sema::CheckRealImagOperand(Expr *&V, SourceLocation Loc) { 694 DefaultFunctionArrayConversion(V); 695 696 // These operators return the element type of a complex type. 697 if (const ComplexType *CT = V->getType()->getAsComplexType()) 698 return CT->getElementType(); 699 700 // Otherwise they pass through real integer and floating point types here. 701 if (V->getType()->isArithmeticType()) 702 return V->getType(); 703 704 // Reject anything else. 705 Diag(Loc, diag::err_realimag_invalid_type, V->getType().getAsString()); 706 return QualType(); 707} 708 709 710 711Action::ExprResult Sema::ActOnPostfixUnaryOp(SourceLocation OpLoc, 712 tok::TokenKind Kind, 713 ExprTy *Input) { 714 UnaryOperator::Opcode Opc; 715 switch (Kind) { 716 default: assert(0 && "Unknown unary op!"); 717 case tok::plusplus: Opc = UnaryOperator::PostInc; break; 718 case tok::minusminus: Opc = UnaryOperator::PostDec; break; 719 } 720 QualType result = CheckIncrementDecrementOperand((Expr *)Input, OpLoc); 721 if (result.isNull()) 722 return true; 723 return new UnaryOperator((Expr *)Input, Opc, result, OpLoc); 724} 725 726Action::ExprResult Sema:: 727ActOnArraySubscriptExpr(ExprTy *Base, SourceLocation LLoc, 728 ExprTy *Idx, SourceLocation RLoc) { 729 Expr *LHSExp = static_cast<Expr*>(Base), *RHSExp = static_cast<Expr*>(Idx); 730 731 // Perform default conversions. 732 DefaultFunctionArrayConversion(LHSExp); 733 DefaultFunctionArrayConversion(RHSExp); 734 735 QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType(); 736 737 // C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent 738 // to the expression *((e1)+(e2)). This means the array "Base" may actually be 739 // in the subscript position. As a result, we need to derive the array base 740 // and index from the expression types. 741 Expr *BaseExpr, *IndexExpr; 742 QualType ResultType; 743 if (const PointerType *PTy = LHSTy->getAsPointerType()) { 744 BaseExpr = LHSExp; 745 IndexExpr = RHSExp; 746 // FIXME: need to deal with const... 747 ResultType = PTy->getPointeeType(); 748 } else if (const PointerType *PTy = RHSTy->getAsPointerType()) { 749 // Handle the uncommon case of "123[Ptr]". 750 BaseExpr = RHSExp; 751 IndexExpr = LHSExp; 752 // FIXME: need to deal with const... 753 ResultType = PTy->getPointeeType(); 754 } else if (const VectorType *VTy = LHSTy->getAsVectorType()) { 755 BaseExpr = LHSExp; // vectors: V[123] 756 IndexExpr = RHSExp; 757 758 // Component access limited to variables (reject vec4.rg[1]). 759 if (!isa<DeclRefExpr>(BaseExpr) && !isa<ArraySubscriptExpr>(BaseExpr) && 760 !isa<ExtVectorElementExpr>(BaseExpr)) 761 return Diag(LLoc, diag::err_ext_vector_component_access, 762 SourceRange(LLoc, RLoc)); 763 // FIXME: need to deal with const... 764 ResultType = VTy->getElementType(); 765 } else { 766 return Diag(LHSExp->getLocStart(), diag::err_typecheck_subscript_value, 767 RHSExp->getSourceRange()); 768 } 769 // C99 6.5.2.1p1 770 if (!IndexExpr->getType()->isIntegerType()) 771 return Diag(IndexExpr->getLocStart(), diag::err_typecheck_subscript, 772 IndexExpr->getSourceRange()); 773 774 // C99 6.5.2.1p1: "shall have type "pointer to *object* type". In practice, 775 // the following check catches trying to index a pointer to a function (e.g. 776 // void (*)(int)) and pointers to incomplete types. Functions are not 777 // objects in C99. 778 if (!ResultType->isObjectType()) 779 return Diag(BaseExpr->getLocStart(), 780 diag::err_typecheck_subscript_not_object, 781 BaseExpr->getType().getAsString(), BaseExpr->getSourceRange()); 782 783 return new ArraySubscriptExpr(LHSExp, RHSExp, ResultType, RLoc); 784} 785 786QualType Sema:: 787CheckExtVectorComponent(QualType baseType, SourceLocation OpLoc, 788 IdentifierInfo &CompName, SourceLocation CompLoc) { 789 const ExtVectorType *vecType = baseType->getAsExtVectorType(); 790 791 // This flag determines whether or not the component is to be treated as a 792 // special name, or a regular GLSL-style component access. 793 bool SpecialComponent = false; 794 795 // The vector accessor can't exceed the number of elements. 796 const char *compStr = CompName.getName(); 797 if (strlen(compStr) > vecType->getNumElements()) { 798 Diag(OpLoc, diag::err_ext_vector_component_exceeds_length, 799 baseType.getAsString(), SourceRange(CompLoc)); 800 return QualType(); 801 } 802 803 // Check that we've found one of the special components, or that the component 804 // names must come from the same set. 805 if (!strcmp(compStr, "hi") || !strcmp(compStr, "lo") || 806 !strcmp(compStr, "e") || !strcmp(compStr, "o")) { 807 SpecialComponent = true; 808 } else if (vecType->getPointAccessorIdx(*compStr) != -1) { 809 do 810 compStr++; 811 while (*compStr && vecType->getPointAccessorIdx(*compStr) != -1); 812 } else if (vecType->getColorAccessorIdx(*compStr) != -1) { 813 do 814 compStr++; 815 while (*compStr && vecType->getColorAccessorIdx(*compStr) != -1); 816 } else if (vecType->getTextureAccessorIdx(*compStr) != -1) { 817 do 818 compStr++; 819 while (*compStr && vecType->getTextureAccessorIdx(*compStr) != -1); 820 } 821 822 if (!SpecialComponent && *compStr) { 823 // We didn't get to the end of the string. This means the component names 824 // didn't come from the same set *or* we encountered an illegal name. 825 Diag(OpLoc, diag::err_ext_vector_component_name_illegal, 826 std::string(compStr,compStr+1), SourceRange(CompLoc)); 827 return QualType(); 828 } 829 // Each component accessor can't exceed the vector type. 830 compStr = CompName.getName(); 831 while (*compStr) { 832 if (vecType->isAccessorWithinNumElements(*compStr)) 833 compStr++; 834 else 835 break; 836 } 837 if (!SpecialComponent && *compStr) { 838 // We didn't get to the end of the string. This means a component accessor 839 // exceeds the number of elements in the vector. 840 Diag(OpLoc, diag::err_ext_vector_component_exceeds_length, 841 baseType.getAsString(), SourceRange(CompLoc)); 842 return QualType(); 843 } 844 845 // If we have a special component name, verify that the current vector length 846 // is an even number, since all special component names return exactly half 847 // the elements. 848 if (SpecialComponent && (vecType->getNumElements() & 1U)) { 849 return QualType(); 850 } 851 852 // The component accessor looks fine - now we need to compute the actual type. 853 // The vector type is implied by the component accessor. For example, 854 // vec4.b is a float, vec4.xy is a vec2, vec4.rgb is a vec3, etc. 855 // vec4.hi, vec4.lo, vec4.e, and vec4.o all return vec2. 856 unsigned CompSize = SpecialComponent ? vecType->getNumElements() / 2 857 : strlen(CompName.getName()); 858 if (CompSize == 1) 859 return vecType->getElementType(); 860 861 QualType VT = Context.getExtVectorType(vecType->getElementType(), CompSize); 862 // Now look up the TypeDefDecl from the vector type. Without this, 863 // diagostics look bad. We want extended vector types to appear built-in. 864 for (unsigned i = 0, E = ExtVectorDecls.size(); i != E; ++i) { 865 if (ExtVectorDecls[i]->getUnderlyingType() == VT) 866 return Context.getTypedefType(ExtVectorDecls[i]); 867 } 868 return VT; // should never get here (a typedef type should always be found). 869} 870 871/// constructSetterName - Return the setter name for the given 872/// identifier, i.e. "set" + Name where the initial character of Name 873/// has been capitalized. 874// FIXME: Merge with same routine in Parser. But where should this 875// live? 876static IdentifierInfo *constructSetterName(IdentifierTable &Idents, 877 const IdentifierInfo *Name) { 878 unsigned N = Name->getLength(); 879 char *SelectorName = new char[3 + N]; 880 memcpy(SelectorName, "set", 3); 881 memcpy(&SelectorName[3], Name->getName(), N); 882 SelectorName[3] = toupper(SelectorName[3]); 883 884 IdentifierInfo *Setter = 885 &Idents.get(SelectorName, &SelectorName[3 + N]); 886 delete[] SelectorName; 887 return Setter; 888} 889 890Action::ExprResult Sema:: 891ActOnMemberReferenceExpr(ExprTy *Base, SourceLocation OpLoc, 892 tok::TokenKind OpKind, SourceLocation MemberLoc, 893 IdentifierInfo &Member) { 894 Expr *BaseExpr = static_cast<Expr *>(Base); 895 assert(BaseExpr && "no record expression"); 896 897 // Perform default conversions. 898 DefaultFunctionArrayConversion(BaseExpr); 899 900 QualType BaseType = BaseExpr->getType(); 901 assert(!BaseType.isNull() && "no type for member expression"); 902 903 // Get the type being accessed in BaseType. If this is an arrow, the BaseExpr 904 // must have pointer type, and the accessed type is the pointee. 905 if (OpKind == tok::arrow) { 906 if (const PointerType *PT = BaseType->getAsPointerType()) 907 BaseType = PT->getPointeeType(); 908 else 909 return Diag(MemberLoc, diag::err_typecheck_member_reference_arrow, 910 BaseType.getAsString(), BaseExpr->getSourceRange()); 911 } 912 913 // Handle field access to simple records. This also handles access to fields 914 // of the ObjC 'id' struct. 915 if (const RecordType *RTy = BaseType->getAsRecordType()) { 916 RecordDecl *RDecl = RTy->getDecl(); 917 if (RTy->isIncompleteType()) 918 return Diag(OpLoc, diag::err_typecheck_incomplete_tag, RDecl->getName(), 919 BaseExpr->getSourceRange()); 920 // The record definition is complete, now make sure the member is valid. 921 FieldDecl *MemberDecl = RDecl->getMember(&Member); 922 if (!MemberDecl) 923 return Diag(MemberLoc, diag::err_typecheck_no_member, Member.getName(), 924 BaseExpr->getSourceRange()); 925 926 // Figure out the type of the member; see C99 6.5.2.3p3 927 // FIXME: Handle address space modifiers 928 QualType MemberType = MemberDecl->getType(); 929 unsigned combinedQualifiers = 930 MemberType.getCVRQualifiers() | BaseType.getCVRQualifiers(); 931 MemberType = MemberType.getQualifiedType(combinedQualifiers); 932 933 return new MemberExpr(BaseExpr, OpKind == tok::arrow, MemberDecl, 934 MemberLoc, MemberType); 935 } 936 937 // Handle access to Objective-C instance variables, such as "Obj->ivar" and 938 // (*Obj).ivar. 939 if (const ObjCInterfaceType *IFTy = BaseType->getAsObjCInterfaceType()) { 940 if (ObjCIvarDecl *IV = IFTy->getDecl()->lookupInstanceVariable(&Member)) 941 return new ObjCIvarRefExpr(IV, IV->getType(), MemberLoc, BaseExpr, 942 OpKind == tok::arrow); 943 return Diag(MemberLoc, diag::err_typecheck_member_reference_ivar, 944 IFTy->getDecl()->getName(), Member.getName(), 945 BaseExpr->getSourceRange()); 946 } 947 948 // Handle Objective-C property access, which is "Obj.property" where Obj is a 949 // pointer to a (potentially qualified) interface type. 950 const PointerType *PTy; 951 const ObjCInterfaceType *IFTy; 952 if (OpKind == tok::period && (PTy = BaseType->getAsPointerType()) && 953 (IFTy = PTy->getPointeeType()->getAsObjCInterfaceType())) { 954 ObjCInterfaceDecl *IFace = IFTy->getDecl(); 955 956 // Search for a declared property first. 957 if (ObjCPropertyDecl *PD = IFace->FindPropertyDeclaration(&Member)) 958 return new ObjCPropertyRefExpr(PD, PD->getType(), MemberLoc, BaseExpr); 959 960 // Check protocols on qualified interfaces. 961 for (ObjCInterfaceType::qual_iterator I = IFTy->qual_begin(), 962 E = IFTy->qual_end(); I != E; ++I) 963 if (ObjCPropertyDecl *PD = (*I)->FindPropertyDeclaration(&Member)) 964 return new ObjCPropertyRefExpr(PD, PD->getType(), MemberLoc, BaseExpr); 965 966 // If that failed, look for an "implicit" property by seeing if the nullary 967 // selector is implemented. 968 969 // FIXME: The logic for looking up nullary and unary selectors should be 970 // shared with the code in ActOnInstanceMessage. 971 972 Selector Sel = PP.getSelectorTable().getNullarySelector(&Member); 973 ObjCMethodDecl *Getter = IFace->lookupInstanceMethod(Sel); 974 975 // If this reference is in an @implementation, check for 'private' methods. 976 if (!Getter) 977 if (ObjCMethodDecl *CurMeth = getCurMethodDecl()) 978 if (ObjCInterfaceDecl *ClassDecl = CurMeth->getClassInterface()) 979 if (ObjCImplementationDecl *ImpDecl = 980 ObjCImplementations[ClassDecl->getIdentifier()]) 981 Getter = ImpDecl->getInstanceMethod(Sel); 982 983 if (Getter) { 984 // If we found a getter then this may be a valid dot-reference, we 985 // need to also look for the matching setter. 986 IdentifierInfo *SetterName = constructSetterName(PP.getIdentifierTable(), 987 &Member); 988 Selector SetterSel = PP.getSelectorTable().getUnarySelector(SetterName); 989 ObjCMethodDecl *Setter = IFace->lookupInstanceMethod(SetterSel); 990 991 if (!Setter) { 992 if (ObjCMethodDecl *CurMeth = getCurMethodDecl()) 993 if (ObjCInterfaceDecl *ClassDecl = CurMeth->getClassInterface()) 994 if (ObjCImplementationDecl *ImpDecl = 995 ObjCImplementations[ClassDecl->getIdentifier()]) 996 Setter = ImpDecl->getInstanceMethod(SetterSel); 997 } 998 999 // FIXME: There are some issues here. First, we are not 1000 // diagnosing accesses to read-only properties because we do not 1001 // know if this is a getter or setter yet. Second, we are 1002 // checking that the type of the setter matches the type we 1003 // expect. 1004 return new ObjCPropertyRefExpr(Getter, Setter, Getter->getResultType(), 1005 MemberLoc, BaseExpr); 1006 } 1007 } 1008 1009 // Handle 'field access' to vectors, such as 'V.xx'. 1010 if (BaseType->isExtVectorType() && OpKind == tok::period) { 1011 // Component access limited to variables (reject vec4.rg.g). 1012 if (!isa<DeclRefExpr>(BaseExpr) && !isa<ArraySubscriptExpr>(BaseExpr) && 1013 !isa<ExtVectorElementExpr>(BaseExpr)) 1014 return Diag(MemberLoc, diag::err_ext_vector_component_access, 1015 BaseExpr->getSourceRange()); 1016 QualType ret = CheckExtVectorComponent(BaseType, OpLoc, Member, MemberLoc); 1017 if (ret.isNull()) 1018 return true; 1019 return new ExtVectorElementExpr(ret, BaseExpr, Member, MemberLoc); 1020 } 1021 1022 return Diag(MemberLoc, diag::err_typecheck_member_reference_struct_union, 1023 BaseType.getAsString(), BaseExpr->getSourceRange()); 1024} 1025 1026/// ActOnCallExpr - Handle a call to Fn with the specified array of arguments. 1027/// This provides the location of the left/right parens and a list of comma 1028/// locations. 1029Action::ExprResult Sema:: 1030ActOnCallExpr(ExprTy *fn, SourceLocation LParenLoc, 1031 ExprTy **args, unsigned NumArgs, 1032 SourceLocation *CommaLocs, SourceLocation RParenLoc) { 1033 Expr *Fn = static_cast<Expr *>(fn); 1034 Expr **Args = reinterpret_cast<Expr**>(args); 1035 assert(Fn && "no function call expression"); 1036 FunctionDecl *FDecl = NULL; 1037 1038 // Promote the function operand. 1039 UsualUnaryConversions(Fn); 1040 1041 // If we're directly calling a function, get the declaration for 1042 // that function. 1043 if (ImplicitCastExpr *IcExpr = dyn_cast<ImplicitCastExpr>(Fn)) 1044 if (DeclRefExpr *DRExpr = dyn_cast<DeclRefExpr>(IcExpr->getSubExpr())) 1045 FDecl = dyn_cast<FunctionDecl>(DRExpr->getDecl()); 1046 1047 // Make the call expr early, before semantic checks. This guarantees cleanup 1048 // of arguments and function on error. 1049 llvm::OwningPtr<CallExpr> TheCall(new CallExpr(Fn, Args, NumArgs, 1050 Context.BoolTy, RParenLoc)); 1051 const FunctionType *FuncT; 1052 if (!Fn->getType()->isBlockPointerType()) { 1053 // C99 6.5.2.2p1 - "The expression that denotes the called function shall 1054 // have type pointer to function". 1055 const PointerType *PT = Fn->getType()->getAsPointerType(); 1056 if (PT == 0) 1057 return Diag(LParenLoc, diag::err_typecheck_call_not_function, 1058 Fn->getSourceRange()); 1059 FuncT = PT->getPointeeType()->getAsFunctionType(); 1060 } else { // This is a block call. 1061 FuncT = Fn->getType()->getAsBlockPointerType()->getPointeeType()-> 1062 getAsFunctionType(); 1063 } 1064 if (FuncT == 0) 1065 return Diag(LParenLoc, diag::err_typecheck_call_not_function, 1066 Fn->getSourceRange()); 1067 1068 // We know the result type of the call, set it. 1069 TheCall->setType(FuncT->getResultType()); 1070 1071 if (const FunctionTypeProto *Proto = dyn_cast<FunctionTypeProto>(FuncT)) { 1072 // C99 6.5.2.2p7 - the arguments are implicitly converted, as if by 1073 // assignment, to the types of the corresponding parameter, ... 1074 unsigned NumArgsInProto = Proto->getNumArgs(); 1075 unsigned NumArgsToCheck = NumArgs; 1076 1077 // If too few arguments are available (and we don't have default 1078 // arguments for the remaining parameters), don't make the call. 1079 if (NumArgs < NumArgsInProto) { 1080 if (FDecl && NumArgs >= FDecl->getMinRequiredArguments()) { 1081 // Use default arguments for missing arguments 1082 NumArgsToCheck = NumArgsInProto; 1083 TheCall->setNumArgs(NumArgsInProto); 1084 } else 1085 return Diag(RParenLoc, 1086 !Fn->getType()->isBlockPointerType() 1087 ? diag::err_typecheck_call_too_few_args 1088 : diag::err_typecheck_block_too_few_args, 1089 Fn->getSourceRange()); 1090 } 1091 1092 // If too many are passed and not variadic, error on the extras and drop 1093 // them. 1094 if (NumArgs > NumArgsInProto) { 1095 if (!Proto->isVariadic()) { 1096 Diag(Args[NumArgsInProto]->getLocStart(), 1097 !Fn->getType()->isBlockPointerType() 1098 ? diag::err_typecheck_call_too_many_args 1099 : diag::err_typecheck_block_too_many_args, 1100 Fn->getSourceRange(), 1101 SourceRange(Args[NumArgsInProto]->getLocStart(), 1102 Args[NumArgs-1]->getLocEnd())); 1103 // This deletes the extra arguments. 1104 TheCall->setNumArgs(NumArgsInProto); 1105 } 1106 NumArgsToCheck = NumArgsInProto; 1107 } 1108 1109 // Continue to check argument types (even if we have too few/many args). 1110 for (unsigned i = 0; i != NumArgsToCheck; i++) { 1111 QualType ProtoArgType = Proto->getArgType(i); 1112 1113 Expr *Arg; 1114 if (i < NumArgs) 1115 Arg = Args[i]; 1116 else 1117 Arg = new CXXDefaultArgExpr(FDecl->getParamDecl(i)); 1118 QualType ArgType = Arg->getType(); 1119 1120 // Compute implicit casts from the operand to the formal argument type. 1121 AssignConvertType ConvTy = 1122 CheckSingleAssignmentConstraints(ProtoArgType, Arg); 1123 TheCall->setArg(i, Arg); 1124 1125 if (DiagnoseAssignmentResult(ConvTy, Arg->getLocStart(), ProtoArgType, 1126 ArgType, Arg, "passing")) 1127 return true; 1128 } 1129 1130 // If this is a variadic call, handle args passed through "...". 1131 if (Proto->isVariadic()) { 1132 // Promote the arguments (C99 6.5.2.2p7). 1133 for (unsigned i = NumArgsInProto; i != NumArgs; i++) { 1134 Expr *Arg = Args[i]; 1135 DefaultArgumentPromotion(Arg); 1136 TheCall->setArg(i, Arg); 1137 } 1138 } 1139 } else { 1140 assert(isa<FunctionTypeNoProto>(FuncT) && "Unknown FunctionType!"); 1141 1142 // Promote the arguments (C99 6.5.2.2p6). 1143 for (unsigned i = 0; i != NumArgs; i++) { 1144 Expr *Arg = Args[i]; 1145 DefaultArgumentPromotion(Arg); 1146 TheCall->setArg(i, Arg); 1147 } 1148 } 1149 1150 // Do special checking on direct calls to functions. 1151 if (FDecl) 1152 return CheckFunctionCall(FDecl, TheCall.take()); 1153 1154 return TheCall.take(); 1155} 1156 1157Action::ExprResult Sema:: 1158ActOnCompoundLiteral(SourceLocation LParenLoc, TypeTy *Ty, 1159 SourceLocation RParenLoc, ExprTy *InitExpr) { 1160 assert((Ty != 0) && "ActOnCompoundLiteral(): missing type"); 1161 QualType literalType = QualType::getFromOpaquePtr(Ty); 1162 // FIXME: put back this assert when initializers are worked out. 1163 //assert((InitExpr != 0) && "ActOnCompoundLiteral(): missing expression"); 1164 Expr *literalExpr = static_cast<Expr*>(InitExpr); 1165 1166 if (literalType->isArrayType()) { 1167 if (literalType->isVariableArrayType()) 1168 return Diag(LParenLoc, 1169 diag::err_variable_object_no_init, 1170 SourceRange(LParenLoc, 1171 literalExpr->getSourceRange().getEnd())); 1172 } else if (literalType->isIncompleteType()) { 1173 return Diag(LParenLoc, 1174 diag::err_typecheck_decl_incomplete_type, 1175 literalType.getAsString(), 1176 SourceRange(LParenLoc, 1177 literalExpr->getSourceRange().getEnd())); 1178 } 1179 1180 if (CheckInitializerTypes(literalExpr, literalType)) 1181 return true; 1182 1183 bool isFileScope = !getCurFunctionDecl() && !getCurMethodDecl(); 1184 if (isFileScope) { // 6.5.2.5p3 1185 if (CheckForConstantInitializer(literalExpr, literalType)) 1186 return true; 1187 } 1188 return new CompoundLiteralExpr(LParenLoc, literalType, literalExpr, isFileScope); 1189} 1190 1191Action::ExprResult Sema:: 1192ActOnInitList(SourceLocation LBraceLoc, ExprTy **initlist, unsigned NumInit, 1193 SourceLocation RBraceLoc) { 1194 Expr **InitList = reinterpret_cast<Expr**>(initlist); 1195 1196 // Semantic analysis for initializers is done by ActOnDeclarator() and 1197 // CheckInitializer() - it requires knowledge of the object being intialized. 1198 1199 InitListExpr *E = new InitListExpr(LBraceLoc, InitList, NumInit, RBraceLoc); 1200 E->setType(Context.VoidTy); // FIXME: just a place holder for now. 1201 return E; 1202} 1203 1204/// CheckCastTypes - Check type constraints for casting between types. 1205bool Sema::CheckCastTypes(SourceRange TyR, QualType castType, Expr *&castExpr) { 1206 UsualUnaryConversions(castExpr); 1207 1208 // C99 6.5.4p2: the cast type needs to be void or scalar and the expression 1209 // type needs to be scalar. 1210 if (castType->isVoidType()) { 1211 // Cast to void allows any expr type. 1212 } else if (!castType->isScalarType() && !castType->isVectorType()) { 1213 // GCC struct/union extension: allow cast to self. 1214 if (Context.getCanonicalType(castType) != 1215 Context.getCanonicalType(castExpr->getType()) || 1216 (!castType->isStructureType() && !castType->isUnionType())) { 1217 // Reject any other conversions to non-scalar types. 1218 return Diag(TyR.getBegin(), diag::err_typecheck_cond_expect_scalar, 1219 castType.getAsString(), castExpr->getSourceRange()); 1220 } 1221 1222 // accept this, but emit an ext-warn. 1223 Diag(TyR.getBegin(), diag::ext_typecheck_cast_nonscalar, 1224 castType.getAsString(), castExpr->getSourceRange()); 1225 } else if (!castExpr->getType()->isScalarType() && 1226 !castExpr->getType()->isVectorType()) { 1227 return Diag(castExpr->getLocStart(), 1228 diag::err_typecheck_expect_scalar_operand, 1229 castExpr->getType().getAsString(),castExpr->getSourceRange()); 1230 } else if (castExpr->getType()->isVectorType()) { 1231 if (CheckVectorCast(TyR, castExpr->getType(), castType)) 1232 return true; 1233 } else if (castType->isVectorType()) { 1234 if (CheckVectorCast(TyR, castType, castExpr->getType())) 1235 return true; 1236 } 1237 return false; 1238} 1239 1240bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty) { 1241 assert(VectorTy->isVectorType() && "Not a vector type!"); 1242 1243 if (Ty->isVectorType() || Ty->isIntegerType()) { 1244 if (Context.getTypeSize(VectorTy) != Context.getTypeSize(Ty)) 1245 return Diag(R.getBegin(), 1246 Ty->isVectorType() ? 1247 diag::err_invalid_conversion_between_vectors : 1248 diag::err_invalid_conversion_between_vector_and_integer, 1249 VectorTy.getAsString().c_str(), 1250 Ty.getAsString().c_str(), R); 1251 } else 1252 return Diag(R.getBegin(), 1253 diag::err_invalid_conversion_between_vector_and_scalar, 1254 VectorTy.getAsString().c_str(), 1255 Ty.getAsString().c_str(), R); 1256 1257 return false; 1258} 1259 1260Action::ExprResult Sema:: 1261ActOnCastExpr(SourceLocation LParenLoc, TypeTy *Ty, 1262 SourceLocation RParenLoc, ExprTy *Op) { 1263 assert((Ty != 0) && (Op != 0) && "ActOnCastExpr(): missing type or expr"); 1264 1265 Expr *castExpr = static_cast<Expr*>(Op); 1266 QualType castType = QualType::getFromOpaquePtr(Ty); 1267 1268 if (CheckCastTypes(SourceRange(LParenLoc, RParenLoc), castType, castExpr)) 1269 return true; 1270 return new ExplicitCastExpr(castType, castExpr, LParenLoc); 1271} 1272 1273/// Note that lex is not null here, even if this is the gnu "x ?: y" extension. 1274/// In that case, lex = cond. 1275inline QualType Sema::CheckConditionalOperands( // C99 6.5.15 1276 Expr *&cond, Expr *&lex, Expr *&rex, SourceLocation questionLoc) { 1277 UsualUnaryConversions(cond); 1278 UsualUnaryConversions(lex); 1279 UsualUnaryConversions(rex); 1280 QualType condT = cond->getType(); 1281 QualType lexT = lex->getType(); 1282 QualType rexT = rex->getType(); 1283 1284 // first, check the condition. 1285 if (!condT->isScalarType()) { // C99 6.5.15p2 1286 Diag(cond->getLocStart(), diag::err_typecheck_cond_expect_scalar, 1287 condT.getAsString()); 1288 return QualType(); 1289 } 1290 1291 // Now check the two expressions. 1292 1293 // If both operands have arithmetic type, do the usual arithmetic conversions 1294 // to find a common type: C99 6.5.15p3,5. 1295 if (lexT->isArithmeticType() && rexT->isArithmeticType()) { 1296 UsualArithmeticConversions(lex, rex); 1297 return lex->getType(); 1298 } 1299 1300 // If both operands are the same structure or union type, the result is that 1301 // type. 1302 if (const RecordType *LHSRT = lexT->getAsRecordType()) { // C99 6.5.15p3 1303 if (const RecordType *RHSRT = rexT->getAsRecordType()) 1304 if (LHSRT->getDecl() == RHSRT->getDecl()) 1305 // "If both the operands have structure or union type, the result has 1306 // that type." This implies that CV qualifiers are dropped. 1307 return lexT.getUnqualifiedType(); 1308 } 1309 1310 // C99 6.5.15p5: "If both operands have void type, the result has void type." 1311 // The following || allows only one side to be void (a GCC-ism). 1312 if (lexT->isVoidType() || rexT->isVoidType()) { 1313 if (!lexT->isVoidType()) 1314 Diag(rex->getLocStart(), diag::ext_typecheck_cond_one_void, 1315 rex->getSourceRange()); 1316 if (!rexT->isVoidType()) 1317 Diag(lex->getLocStart(), diag::ext_typecheck_cond_one_void, 1318 lex->getSourceRange()); 1319 ImpCastExprToType(lex, Context.VoidTy); 1320 ImpCastExprToType(rex, Context.VoidTy); 1321 return Context.VoidTy; 1322 } 1323 // C99 6.5.15p6 - "if one operand is a null pointer constant, the result has 1324 // the type of the other operand." 1325 if ((lexT->isPointerType() || lexT->isBlockPointerType() || 1326 Context.isObjCObjectPointerType(lexT)) && 1327 rex->isNullPointerConstant(Context)) { 1328 ImpCastExprToType(rex, lexT); // promote the null to a pointer. 1329 return lexT; 1330 } 1331 if ((rexT->isPointerType() || rexT->isBlockPointerType() || 1332 Context.isObjCObjectPointerType(rexT)) && 1333 lex->isNullPointerConstant(Context)) { 1334 ImpCastExprToType(lex, rexT); // promote the null to a pointer. 1335 return rexT; 1336 } 1337 // Handle the case where both operands are pointers before we handle null 1338 // pointer constants in case both operands are null pointer constants. 1339 if (const PointerType *LHSPT = lexT->getAsPointerType()) { // C99 6.5.15p3,6 1340 if (const PointerType *RHSPT = rexT->getAsPointerType()) { 1341 // get the "pointed to" types 1342 QualType lhptee = LHSPT->getPointeeType(); 1343 QualType rhptee = RHSPT->getPointeeType(); 1344 1345 // ignore qualifiers on void (C99 6.5.15p3, clause 6) 1346 if (lhptee->isVoidType() && 1347 rhptee->isIncompleteOrObjectType()) { 1348 // Figure out necessary qualifiers (C99 6.5.15p6) 1349 QualType destPointee=lhptee.getQualifiedType(rhptee.getCVRQualifiers()); 1350 QualType destType = Context.getPointerType(destPointee); 1351 ImpCastExprToType(lex, destType); // add qualifiers if necessary 1352 ImpCastExprToType(rex, destType); // promote to void* 1353 return destType; 1354 } 1355 if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) { 1356 QualType destPointee=rhptee.getQualifiedType(lhptee.getCVRQualifiers()); 1357 QualType destType = Context.getPointerType(destPointee); 1358 ImpCastExprToType(lex, destType); // add qualifiers if necessary 1359 ImpCastExprToType(rex, destType); // promote to void* 1360 return destType; 1361 } 1362 1363 QualType compositeType = lexT; 1364 1365 // If either type is an Objective-C object type then check 1366 // compatibility according to Objective-C. 1367 if (Context.isObjCObjectPointerType(lexT) || 1368 Context.isObjCObjectPointerType(rexT)) { 1369 // If both operands are interfaces and either operand can be 1370 // assigned to the other, use that type as the composite 1371 // type. This allows 1372 // xxx ? (A*) a : (B*) b 1373 // where B is a subclass of A. 1374 // 1375 // Additionally, as for assignment, if either type is 'id' 1376 // allow silent coercion. Finally, if the types are 1377 // incompatible then make sure to use 'id' as the composite 1378 // type so the result is acceptable for sending messages to. 1379 1380 // FIXME: This code should not be localized to here. Also this 1381 // should use a compatible check instead of abusing the 1382 // canAssignObjCInterfaces code. 1383 const ObjCInterfaceType* LHSIface = lhptee->getAsObjCInterfaceType(); 1384 const ObjCInterfaceType* RHSIface = rhptee->getAsObjCInterfaceType(); 1385 if (LHSIface && RHSIface && 1386 Context.canAssignObjCInterfaces(LHSIface, RHSIface)) { 1387 compositeType = lexT; 1388 } else if (LHSIface && RHSIface && 1389 Context.canAssignObjCInterfaces(LHSIface, RHSIface)) { 1390 compositeType = rexT; 1391 } else if (Context.isObjCIdType(lhptee) || 1392 Context.isObjCIdType(rhptee)) { 1393 // FIXME: This code looks wrong, because isObjCIdType checks 1394 // the struct but getObjCIdType returns the pointer to 1395 // struct. This is horrible and should be fixed. 1396 compositeType = Context.getObjCIdType(); 1397 } else { 1398 QualType incompatTy = Context.getObjCIdType(); 1399 ImpCastExprToType(lex, incompatTy); 1400 ImpCastExprToType(rex, incompatTy); 1401 return incompatTy; 1402 } 1403 } else if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 1404 rhptee.getUnqualifiedType())) { 1405 Diag(questionLoc, diag::warn_typecheck_cond_incompatible_pointers, 1406 lexT.getAsString(), rexT.getAsString(), 1407 lex->getSourceRange(), rex->getSourceRange()); 1408 // In this situation, we assume void* type. No especially good 1409 // reason, but this is what gcc does, and we do have to pick 1410 // to get a consistent AST. 1411 QualType incompatTy = Context.getPointerType(Context.VoidTy); 1412 ImpCastExprToType(lex, incompatTy); 1413 ImpCastExprToType(rex, incompatTy); 1414 return incompatTy; 1415 } 1416 // The pointer types are compatible. 1417 // C99 6.5.15p6: If both operands are pointers to compatible types *or* to 1418 // differently qualified versions of compatible types, the result type is 1419 // a pointer to an appropriately qualified version of the *composite* 1420 // type. 1421 // FIXME: Need to calculate the composite type. 1422 // FIXME: Need to add qualifiers 1423 ImpCastExprToType(lex, compositeType); 1424 ImpCastExprToType(rex, compositeType); 1425 return compositeType; 1426 } 1427 } 1428 // Need to handle "id<xx>" explicitly. Unlike "id", whose canonical type 1429 // evaluates to "struct objc_object *" (and is handled above when comparing 1430 // id with statically typed objects). 1431 if (lexT->isObjCQualifiedIdType() || rexT->isObjCQualifiedIdType()) { 1432 // GCC allows qualified id and any Objective-C type to devolve to 1433 // id. Currently localizing to here until clear this should be 1434 // part of ObjCQualifiedIdTypesAreCompatible. 1435 if (ObjCQualifiedIdTypesAreCompatible(lexT, rexT, true) || 1436 (lexT->isObjCQualifiedIdType() && 1437 Context.isObjCObjectPointerType(rexT)) || 1438 (rexT->isObjCQualifiedIdType() && 1439 Context.isObjCObjectPointerType(lexT))) { 1440 // FIXME: This is not the correct composite type. This only 1441 // happens to work because id can more or less be used anywhere, 1442 // however this may change the type of method sends. 1443 // FIXME: gcc adds some type-checking of the arguments and emits 1444 // (confusing) incompatible comparison warnings in some 1445 // cases. Investigate. 1446 QualType compositeType = Context.getObjCIdType(); 1447 ImpCastExprToType(lex, compositeType); 1448 ImpCastExprToType(rex, compositeType); 1449 return compositeType; 1450 } 1451 } 1452 1453 // Selection between block pointer types is ok as long as they are the same. 1454 if (lexT->isBlockPointerType() && rexT->isBlockPointerType() && 1455 Context.getCanonicalType(lexT) == Context.getCanonicalType(rexT)) 1456 return lexT; 1457 1458 // Otherwise, the operands are not compatible. 1459 Diag(questionLoc, diag::err_typecheck_cond_incompatible_operands, 1460 lexT.getAsString(), rexT.getAsString(), 1461 lex->getSourceRange(), rex->getSourceRange()); 1462 return QualType(); 1463} 1464 1465/// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null 1466/// in the case of a the GNU conditional expr extension. 1467Action::ExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc, 1468 SourceLocation ColonLoc, 1469 ExprTy *Cond, ExprTy *LHS, 1470 ExprTy *RHS) { 1471 Expr *CondExpr = (Expr *) Cond; 1472 Expr *LHSExpr = (Expr *) LHS, *RHSExpr = (Expr *) RHS; 1473 1474 // If this is the gnu "x ?: y" extension, analyze the types as though the LHS 1475 // was the condition. 1476 bool isLHSNull = LHSExpr == 0; 1477 if (isLHSNull) 1478 LHSExpr = CondExpr; 1479 1480 QualType result = CheckConditionalOperands(CondExpr, LHSExpr, 1481 RHSExpr, QuestionLoc); 1482 if (result.isNull()) 1483 return true; 1484 return new ConditionalOperator(CondExpr, isLHSNull ? 0 : LHSExpr, 1485 RHSExpr, result); 1486} 1487 1488 1489// CheckPointerTypesForAssignment - This is a very tricky routine (despite 1490// being closely modeled after the C99 spec:-). The odd characteristic of this 1491// routine is it effectively iqnores the qualifiers on the top level pointee. 1492// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3]. 1493// FIXME: add a couple examples in this comment. 1494Sema::AssignConvertType 1495Sema::CheckPointerTypesForAssignment(QualType lhsType, QualType rhsType) { 1496 QualType lhptee, rhptee; 1497 1498 // get the "pointed to" type (ignoring qualifiers at the top level) 1499 lhptee = lhsType->getAsPointerType()->getPointeeType(); 1500 rhptee = rhsType->getAsPointerType()->getPointeeType(); 1501 1502 // make sure we operate on the canonical type 1503 lhptee = Context.getCanonicalType(lhptee); 1504 rhptee = Context.getCanonicalType(rhptee); 1505 1506 AssignConvertType ConvTy = Compatible; 1507 1508 // C99 6.5.16.1p1: This following citation is common to constraints 1509 // 3 & 4 (below). ...and the type *pointed to* by the left has all the 1510 // qualifiers of the type *pointed to* by the right; 1511 // FIXME: Handle ASQualType 1512 if ((lhptee.getCVRQualifiers() & rhptee.getCVRQualifiers()) != 1513 rhptee.getCVRQualifiers()) 1514 ConvTy = CompatiblePointerDiscardsQualifiers; 1515 1516 // C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or 1517 // incomplete type and the other is a pointer to a qualified or unqualified 1518 // version of void... 1519 if (lhptee->isVoidType()) { 1520 if (rhptee->isIncompleteOrObjectType()) 1521 return ConvTy; 1522 1523 // As an extension, we allow cast to/from void* to function pointer. 1524 assert(rhptee->isFunctionType()); 1525 return FunctionVoidPointer; 1526 } 1527 1528 if (rhptee->isVoidType()) { 1529 if (lhptee->isIncompleteOrObjectType()) 1530 return ConvTy; 1531 1532 // As an extension, we allow cast to/from void* to function pointer. 1533 assert(lhptee->isFunctionType()); 1534 return FunctionVoidPointer; 1535 } 1536 1537 // Check for ObjC interfaces 1538 const ObjCInterfaceType* LHSIface = lhptee->getAsObjCInterfaceType(); 1539 const ObjCInterfaceType* RHSIface = rhptee->getAsObjCInterfaceType(); 1540 if (LHSIface && RHSIface && 1541 Context.canAssignObjCInterfaces(LHSIface, RHSIface)) 1542 return ConvTy; 1543 1544 // ID acts sort of like void* for ObjC interfaces 1545 if (LHSIface && Context.isObjCIdType(rhptee)) 1546 return ConvTy; 1547 if (RHSIface && Context.isObjCIdType(lhptee)) 1548 return ConvTy; 1549 1550 // C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or 1551 // unqualified versions of compatible types, ... 1552 if (!Context.typesAreCompatible(lhptee.getUnqualifiedType(), 1553 rhptee.getUnqualifiedType())) 1554 return IncompatiblePointer; // this "trumps" PointerAssignDiscardsQualifiers 1555 return ConvTy; 1556} 1557 1558/// CheckBlockPointerTypesForAssignment - This routine determines whether two 1559/// block pointer types are compatible or whether a block and normal pointer 1560/// are compatible. It is more restrict than comparing two function pointer 1561// types. 1562Sema::AssignConvertType 1563Sema::CheckBlockPointerTypesForAssignment(QualType lhsType, 1564 QualType rhsType) { 1565 QualType lhptee, rhptee; 1566 1567 // get the "pointed to" type (ignoring qualifiers at the top level) 1568 lhptee = lhsType->getAsBlockPointerType()->getPointeeType(); 1569 rhptee = rhsType->getAsBlockPointerType()->getPointeeType(); 1570 1571 // make sure we operate on the canonical type 1572 lhptee = Context.getCanonicalType(lhptee); 1573 rhptee = Context.getCanonicalType(rhptee); 1574 1575 AssignConvertType ConvTy = Compatible; 1576 1577 // For blocks we enforce that qualifiers are identical. 1578 if (lhptee.getCVRQualifiers() != rhptee.getCVRQualifiers()) 1579 ConvTy = CompatiblePointerDiscardsQualifiers; 1580 1581 if (!Context.typesAreBlockCompatible(lhptee, rhptee)) 1582 return IncompatibleBlockPointer; 1583 return ConvTy; 1584} 1585 1586/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently 1587/// has code to accommodate several GCC extensions when type checking 1588/// pointers. Here are some objectionable examples that GCC considers warnings: 1589/// 1590/// int a, *pint; 1591/// short *pshort; 1592/// struct foo *pfoo; 1593/// 1594/// pint = pshort; // warning: assignment from incompatible pointer type 1595/// a = pint; // warning: assignment makes integer from pointer without a cast 1596/// pint = a; // warning: assignment makes pointer from integer without a cast 1597/// pint = pfoo; // warning: assignment from incompatible pointer type 1598/// 1599/// As a result, the code for dealing with pointers is more complex than the 1600/// C99 spec dictates. 1601/// 1602Sema::AssignConvertType 1603Sema::CheckAssignmentConstraints(QualType lhsType, QualType rhsType) { 1604 // Get canonical types. We're not formatting these types, just comparing 1605 // them. 1606 lhsType = Context.getCanonicalType(lhsType).getUnqualifiedType(); 1607 rhsType = Context.getCanonicalType(rhsType).getUnqualifiedType(); 1608 1609 if (lhsType == rhsType) 1610 return Compatible; // Common case: fast path an exact match. 1611 1612 if (lhsType->isReferenceType() || rhsType->isReferenceType()) { 1613 if (Context.typesAreCompatible(lhsType, rhsType)) 1614 return Compatible; 1615 return Incompatible; 1616 } 1617 1618 if (lhsType->isObjCQualifiedIdType() || rhsType->isObjCQualifiedIdType()) { 1619 if (ObjCQualifiedIdTypesAreCompatible(lhsType, rhsType, false)) 1620 return Compatible; 1621 // Relax integer conversions like we do for pointers below. 1622 if (rhsType->isIntegerType()) 1623 return IntToPointer; 1624 if (lhsType->isIntegerType()) 1625 return PointerToInt; 1626 return Incompatible; 1627 } 1628 1629 if (lhsType->isVectorType() || rhsType->isVectorType()) { 1630 // For ExtVector, allow vector splats; float -> <n x float> 1631 if (const ExtVectorType *LV = lhsType->getAsExtVectorType()) 1632 if (LV->getElementType() == rhsType) 1633 return Compatible; 1634 1635 // If we are allowing lax vector conversions, and LHS and RHS are both 1636 // vectors, the total size only needs to be the same. This is a bitcast; 1637 // no bits are changed but the result type is different. 1638 if (getLangOptions().LaxVectorConversions && 1639 lhsType->isVectorType() && rhsType->isVectorType()) { 1640 if (Context.getTypeSize(lhsType) == Context.getTypeSize(rhsType)) 1641 return Compatible; 1642 } 1643 return Incompatible; 1644 } 1645 1646 if (lhsType->isArithmeticType() && rhsType->isArithmeticType()) 1647 return Compatible; 1648 1649 if (isa<PointerType>(lhsType)) { 1650 if (rhsType->isIntegerType()) 1651 return IntToPointer; 1652 1653 if (isa<PointerType>(rhsType)) 1654 return CheckPointerTypesForAssignment(lhsType, rhsType); 1655 1656 if (rhsType->getAsBlockPointerType()) { 1657 if (lhsType->getAsPointerType()->getPointeeType()->isVoidType()) 1658 return BlockVoidPointer; 1659 1660 // Treat block pointers as objects. 1661 if (getLangOptions().ObjC1 && 1662 lhsType == Context.getCanonicalType(Context.getObjCIdType())) 1663 return Compatible; 1664 } 1665 return Incompatible; 1666 } 1667 1668 if (isa<BlockPointerType>(lhsType)) { 1669 if (rhsType->isIntegerType()) 1670 return IntToPointer; 1671 1672 // Treat block pointers as objects. 1673 if (getLangOptions().ObjC1 && 1674 rhsType == Context.getCanonicalType(Context.getObjCIdType())) 1675 return Compatible; 1676 1677 if (rhsType->isBlockPointerType()) 1678 return CheckBlockPointerTypesForAssignment(lhsType, rhsType); 1679 1680 if (const PointerType *RHSPT = rhsType->getAsPointerType()) { 1681 if (RHSPT->getPointeeType()->isVoidType()) 1682 return BlockVoidPointer; 1683 } 1684 return Incompatible; 1685 } 1686 1687 if (isa<PointerType>(rhsType)) { 1688 // C99 6.5.16.1p1: the left operand is _Bool and the right is a pointer. 1689 if (lhsType == Context.BoolTy) 1690 return Compatible; 1691 1692 if (lhsType->isIntegerType()) 1693 return PointerToInt; 1694 1695 if (isa<PointerType>(lhsType)) 1696 return CheckPointerTypesForAssignment(lhsType, rhsType); 1697 1698 if (isa<BlockPointerType>(lhsType) && 1699 rhsType->getAsPointerType()->getPointeeType()->isVoidType()) 1700 return BlockVoidPointer; 1701 return Incompatible; 1702 } 1703 1704 if (isa<TagType>(lhsType) && isa<TagType>(rhsType)) { 1705 if (Context.typesAreCompatible(lhsType, rhsType)) 1706 return Compatible; 1707 } 1708 return Incompatible; 1709} 1710 1711Sema::AssignConvertType 1712Sema::CheckSingleAssignmentConstraints(QualType lhsType, Expr *&rExpr) { 1713 // C99 6.5.16.1p1: the left operand is a pointer and the right is 1714 // a null pointer constant. 1715 if ((lhsType->isPointerType() || lhsType->isObjCQualifiedIdType() || 1716 lhsType->isBlockPointerType()) 1717 && rExpr->isNullPointerConstant(Context)) { 1718 ImpCastExprToType(rExpr, lhsType); 1719 return Compatible; 1720 } 1721 1722 // We don't allow conversion of non-null-pointer constants to integers. 1723 if (lhsType->isBlockPointerType() && rExpr->getType()->isIntegerType()) 1724 return IntToBlockPointer; 1725 1726 // This check seems unnatural, however it is necessary to ensure the proper 1727 // conversion of functions/arrays. If the conversion were done for all 1728 // DeclExpr's (created by ActOnIdentifierExpr), it would mess up the unary 1729 // expressions that surpress this implicit conversion (&, sizeof). 1730 // 1731 // Suppress this for references: C99 8.5.3p5. FIXME: revisit when references 1732 // are better understood. 1733 if (!lhsType->isReferenceType()) 1734 DefaultFunctionArrayConversion(rExpr); 1735 1736 Sema::AssignConvertType result = 1737 CheckAssignmentConstraints(lhsType, rExpr->getType()); 1738 1739 // C99 6.5.16.1p2: The value of the right operand is converted to the 1740 // type of the assignment expression. 1741 if (rExpr->getType() != lhsType) 1742 ImpCastExprToType(rExpr, lhsType); 1743 return result; 1744} 1745 1746Sema::AssignConvertType 1747Sema::CheckCompoundAssignmentConstraints(QualType lhsType, QualType rhsType) { 1748 return CheckAssignmentConstraints(lhsType, rhsType); 1749} 1750 1751QualType Sema::InvalidOperands(SourceLocation loc, Expr *&lex, Expr *&rex) { 1752 Diag(loc, diag::err_typecheck_invalid_operands, 1753 lex->getType().getAsString(), rex->getType().getAsString(), 1754 lex->getSourceRange(), rex->getSourceRange()); 1755 return QualType(); 1756} 1757 1758inline QualType Sema::CheckVectorOperands(SourceLocation loc, Expr *&lex, 1759 Expr *&rex) { 1760 // For conversion purposes, we ignore any qualifiers. 1761 // For example, "const float" and "float" are equivalent. 1762 QualType lhsType = 1763 Context.getCanonicalType(lex->getType()).getUnqualifiedType(); 1764 QualType rhsType = 1765 Context.getCanonicalType(rex->getType()).getUnqualifiedType(); 1766 1767 // If the vector types are identical, return. 1768 if (lhsType == rhsType) 1769 return lhsType; 1770 1771 // Handle the case of a vector & extvector type of the same size and element 1772 // type. It would be nice if we only had one vector type someday. 1773 if (getLangOptions().LaxVectorConversions) 1774 if (const VectorType *LV = lhsType->getAsVectorType()) 1775 if (const VectorType *RV = rhsType->getAsVectorType()) 1776 if (LV->getElementType() == RV->getElementType() && 1777 LV->getNumElements() == RV->getNumElements()) 1778 return lhsType->isExtVectorType() ? lhsType : rhsType; 1779 1780 // If the lhs is an extended vector and the rhs is a scalar of the same type 1781 // or a literal, promote the rhs to the vector type. 1782 if (const ExtVectorType *V = lhsType->getAsExtVectorType()) { 1783 QualType eltType = V->getElementType(); 1784 1785 if ((eltType->getAsBuiltinType() == rhsType->getAsBuiltinType()) || 1786 (eltType->isIntegerType() && isa<IntegerLiteral>(rex)) || 1787 (eltType->isFloatingType() && isa<FloatingLiteral>(rex))) { 1788 ImpCastExprToType(rex, lhsType); 1789 return lhsType; 1790 } 1791 } 1792 1793 // If the rhs is an extended vector and the lhs is a scalar of the same type, 1794 // promote the lhs to the vector type. 1795 if (const ExtVectorType *V = rhsType->getAsExtVectorType()) { 1796 QualType eltType = V->getElementType(); 1797 1798 if ((eltType->getAsBuiltinType() == lhsType->getAsBuiltinType()) || 1799 (eltType->isIntegerType() && isa<IntegerLiteral>(lex)) || 1800 (eltType->isFloatingType() && isa<FloatingLiteral>(lex))) { 1801 ImpCastExprToType(lex, rhsType); 1802 return rhsType; 1803 } 1804 } 1805 1806 // You cannot convert between vector values of different size. 1807 Diag(loc, diag::err_typecheck_vector_not_convertable, 1808 lex->getType().getAsString(), rex->getType().getAsString(), 1809 lex->getSourceRange(), rex->getSourceRange()); 1810 return QualType(); 1811} 1812 1813inline QualType Sema::CheckMultiplyDivideOperands( 1814 Expr *&lex, Expr *&rex, SourceLocation loc, bool isCompAssign) 1815{ 1816 QualType lhsType = lex->getType(), rhsType = rex->getType(); 1817 1818 if (lhsType->isVectorType() || rhsType->isVectorType()) 1819 return CheckVectorOperands(loc, lex, rex); 1820 1821 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 1822 1823 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 1824 return compType; 1825 return InvalidOperands(loc, lex, rex); 1826} 1827 1828inline QualType Sema::CheckRemainderOperands( 1829 Expr *&lex, Expr *&rex, SourceLocation loc, bool isCompAssign) 1830{ 1831 QualType lhsType = lex->getType(), rhsType = rex->getType(); 1832 1833 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 1834 1835 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 1836 return compType; 1837 return InvalidOperands(loc, lex, rex); 1838} 1839 1840inline QualType Sema::CheckAdditionOperands( // C99 6.5.6 1841 Expr *&lex, Expr *&rex, SourceLocation loc, bool isCompAssign) 1842{ 1843 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 1844 return CheckVectorOperands(loc, lex, rex); 1845 1846 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 1847 1848 // handle the common case first (both operands are arithmetic). 1849 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 1850 return compType; 1851 1852 // Put any potential pointer into PExp 1853 Expr* PExp = lex, *IExp = rex; 1854 if (IExp->getType()->isPointerType()) 1855 std::swap(PExp, IExp); 1856 1857 if (const PointerType* PTy = PExp->getType()->getAsPointerType()) { 1858 if (IExp->getType()->isIntegerType()) { 1859 // Check for arithmetic on pointers to incomplete types 1860 if (!PTy->getPointeeType()->isObjectType()) { 1861 if (PTy->getPointeeType()->isVoidType()) { 1862 Diag(loc, diag::ext_gnu_void_ptr, 1863 lex->getSourceRange(), rex->getSourceRange()); 1864 } else { 1865 Diag(loc, diag::err_typecheck_arithmetic_incomplete_type, 1866 lex->getType().getAsString(), lex->getSourceRange()); 1867 return QualType(); 1868 } 1869 } 1870 return PExp->getType(); 1871 } 1872 } 1873 1874 return InvalidOperands(loc, lex, rex); 1875} 1876 1877// C99 6.5.6 1878QualType Sema::CheckSubtractionOperands(Expr *&lex, Expr *&rex, 1879 SourceLocation loc, bool isCompAssign) { 1880 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 1881 return CheckVectorOperands(loc, lex, rex); 1882 1883 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 1884 1885 // Enforce type constraints: C99 6.5.6p3. 1886 1887 // Handle the common case first (both operands are arithmetic). 1888 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 1889 return compType; 1890 1891 // Either ptr - int or ptr - ptr. 1892 if (const PointerType *LHSPTy = lex->getType()->getAsPointerType()) { 1893 QualType lpointee = LHSPTy->getPointeeType(); 1894 1895 // The LHS must be an object type, not incomplete, function, etc. 1896 if (!lpointee->isObjectType()) { 1897 // Handle the GNU void* extension. 1898 if (lpointee->isVoidType()) { 1899 Diag(loc, diag::ext_gnu_void_ptr, 1900 lex->getSourceRange(), rex->getSourceRange()); 1901 } else { 1902 Diag(loc, diag::err_typecheck_sub_ptr_object, 1903 lex->getType().getAsString(), lex->getSourceRange()); 1904 return QualType(); 1905 } 1906 } 1907 1908 // The result type of a pointer-int computation is the pointer type. 1909 if (rex->getType()->isIntegerType()) 1910 return lex->getType(); 1911 1912 // Handle pointer-pointer subtractions. 1913 if (const PointerType *RHSPTy = rex->getType()->getAsPointerType()) { 1914 QualType rpointee = RHSPTy->getPointeeType(); 1915 1916 // RHS must be an object type, unless void (GNU). 1917 if (!rpointee->isObjectType()) { 1918 // Handle the GNU void* extension. 1919 if (rpointee->isVoidType()) { 1920 if (!lpointee->isVoidType()) 1921 Diag(loc, diag::ext_gnu_void_ptr, 1922 lex->getSourceRange(), rex->getSourceRange()); 1923 } else { 1924 Diag(loc, diag::err_typecheck_sub_ptr_object, 1925 rex->getType().getAsString(), rex->getSourceRange()); 1926 return QualType(); 1927 } 1928 } 1929 1930 // Pointee types must be compatible. 1931 if (!Context.typesAreCompatible( 1932 Context.getCanonicalType(lpointee).getUnqualifiedType(), 1933 Context.getCanonicalType(rpointee).getUnqualifiedType())) { 1934 Diag(loc, diag::err_typecheck_sub_ptr_compatible, 1935 lex->getType().getAsString(), rex->getType().getAsString(), 1936 lex->getSourceRange(), rex->getSourceRange()); 1937 return QualType(); 1938 } 1939 1940 return Context.getPointerDiffType(); 1941 } 1942 } 1943 1944 return InvalidOperands(loc, lex, rex); 1945} 1946 1947// C99 6.5.7 1948QualType Sema::CheckShiftOperands(Expr *&lex, Expr *&rex, SourceLocation loc, 1949 bool isCompAssign) { 1950 // C99 6.5.7p2: Each of the operands shall have integer type. 1951 if (!lex->getType()->isIntegerType() || !rex->getType()->isIntegerType()) 1952 return InvalidOperands(loc, lex, rex); 1953 1954 // Shifts don't perform usual arithmetic conversions, they just do integer 1955 // promotions on each operand. C99 6.5.7p3 1956 if (!isCompAssign) 1957 UsualUnaryConversions(lex); 1958 UsualUnaryConversions(rex); 1959 1960 // "The type of the result is that of the promoted left operand." 1961 return lex->getType(); 1962} 1963 1964static bool areComparableObjCInterfaces(QualType LHS, QualType RHS, 1965 ASTContext& Context) { 1966 const ObjCInterfaceType* LHSIface = LHS->getAsObjCInterfaceType(); 1967 const ObjCInterfaceType* RHSIface = RHS->getAsObjCInterfaceType(); 1968 // ID acts sort of like void* for ObjC interfaces 1969 if (LHSIface && Context.isObjCIdType(RHS)) 1970 return true; 1971 if (RHSIface && Context.isObjCIdType(LHS)) 1972 return true; 1973 if (!LHSIface || !RHSIface) 1974 return false; 1975 return Context.canAssignObjCInterfaces(LHSIface, RHSIface) || 1976 Context.canAssignObjCInterfaces(RHSIface, LHSIface); 1977} 1978 1979// C99 6.5.8 1980QualType Sema::CheckCompareOperands(Expr *&lex, Expr *&rex, SourceLocation loc, 1981 bool isRelational) { 1982 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 1983 return CheckVectorCompareOperands(lex, rex, loc, isRelational); 1984 1985 // C99 6.5.8p3 / C99 6.5.9p4 1986 if (lex->getType()->isArithmeticType() && rex->getType()->isArithmeticType()) 1987 UsualArithmeticConversions(lex, rex); 1988 else { 1989 UsualUnaryConversions(lex); 1990 UsualUnaryConversions(rex); 1991 } 1992 QualType lType = lex->getType(); 1993 QualType rType = rex->getType(); 1994 1995 // For non-floating point types, check for self-comparisons of the form 1996 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 1997 // often indicate logic errors in the program. 1998 if (!lType->isFloatingType()) { 1999 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(lex->IgnoreParens())) 2000 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(rex->IgnoreParens())) 2001 if (DRL->getDecl() == DRR->getDecl()) 2002 Diag(loc, diag::warn_selfcomparison); 2003 } 2004 2005 if (isRelational) { 2006 if (lType->isRealType() && rType->isRealType()) 2007 return Context.IntTy; 2008 } else { 2009 // Check for comparisons of floating point operands using != and ==. 2010 if (lType->isFloatingType()) { 2011 assert (rType->isFloatingType()); 2012 CheckFloatComparison(loc,lex,rex); 2013 } 2014 2015 if (lType->isArithmeticType() && rType->isArithmeticType()) 2016 return Context.IntTy; 2017 } 2018 2019 bool LHSIsNull = lex->isNullPointerConstant(Context); 2020 bool RHSIsNull = rex->isNullPointerConstant(Context); 2021 2022 // All of the following pointer related warnings are GCC extensions, except 2023 // when handling null pointer constants. One day, we can consider making them 2024 // errors (when -pedantic-errors is enabled). 2025 if (lType->isPointerType() && rType->isPointerType()) { // C99 6.5.8p2 2026 QualType LCanPointeeTy = 2027 Context.getCanonicalType(lType->getAsPointerType()->getPointeeType()); 2028 QualType RCanPointeeTy = 2029 Context.getCanonicalType(rType->getAsPointerType()->getPointeeType()); 2030 2031 if (!LHSIsNull && !RHSIsNull && // C99 6.5.9p2 2032 !LCanPointeeTy->isVoidType() && !RCanPointeeTy->isVoidType() && 2033 !Context.typesAreCompatible(LCanPointeeTy.getUnqualifiedType(), 2034 RCanPointeeTy.getUnqualifiedType()) && 2035 !areComparableObjCInterfaces(LCanPointeeTy, RCanPointeeTy, Context)) { 2036 Diag(loc, diag::ext_typecheck_comparison_of_distinct_pointers, 2037 lType.getAsString(), rType.getAsString(), 2038 lex->getSourceRange(), rex->getSourceRange()); 2039 } 2040 ImpCastExprToType(rex, lType); // promote the pointer to pointer 2041 return Context.IntTy; 2042 } 2043 // Handle block pointer types. 2044 if (lType->isBlockPointerType() && rType->isBlockPointerType()) { 2045 QualType lpointee = lType->getAsBlockPointerType()->getPointeeType(); 2046 QualType rpointee = rType->getAsBlockPointerType()->getPointeeType(); 2047 2048 if (!LHSIsNull && !RHSIsNull && 2049 !Context.typesAreBlockCompatible(lpointee, rpointee)) { 2050 Diag(loc, diag::err_typecheck_comparison_of_distinct_blocks, 2051 lType.getAsString(), rType.getAsString(), 2052 lex->getSourceRange(), rex->getSourceRange()); 2053 } 2054 ImpCastExprToType(rex, lType); // promote the pointer to pointer 2055 return Context.IntTy; 2056 } 2057 // Allow block pointers to be compared with null pointer constants. 2058 if ((lType->isBlockPointerType() && rType->isPointerType()) || 2059 (lType->isPointerType() && rType->isBlockPointerType())) { 2060 if (!LHSIsNull && !RHSIsNull) { 2061 Diag(loc, diag::err_typecheck_comparison_of_distinct_blocks, 2062 lType.getAsString(), rType.getAsString(), 2063 lex->getSourceRange(), rex->getSourceRange()); 2064 } 2065 ImpCastExprToType(rex, lType); // promote the pointer to pointer 2066 return Context.IntTy; 2067 } 2068 2069 if ((lType->isObjCQualifiedIdType() || rType->isObjCQualifiedIdType())) { 2070 if (ObjCQualifiedIdTypesAreCompatible(lType, rType, true)) { 2071 ImpCastExprToType(rex, lType); 2072 return Context.IntTy; 2073 } 2074 } 2075 if ((lType->isPointerType() || lType->isObjCQualifiedIdType()) && 2076 rType->isIntegerType()) { 2077 if (!RHSIsNull) 2078 Diag(loc, diag::ext_typecheck_comparison_of_pointer_integer, 2079 lType.getAsString(), rType.getAsString(), 2080 lex->getSourceRange(), rex->getSourceRange()); 2081 ImpCastExprToType(rex, lType); // promote the integer to pointer 2082 return Context.IntTy; 2083 } 2084 if (lType->isIntegerType() && 2085 (rType->isPointerType() || rType->isObjCQualifiedIdType())) { 2086 if (!LHSIsNull) 2087 Diag(loc, diag::ext_typecheck_comparison_of_pointer_integer, 2088 lType.getAsString(), rType.getAsString(), 2089 lex->getSourceRange(), rex->getSourceRange()); 2090 ImpCastExprToType(lex, rType); // promote the integer to pointer 2091 return Context.IntTy; 2092 } 2093 // Handle block pointers. 2094 if (lType->isBlockPointerType() && rType->isIntegerType()) { 2095 if (!RHSIsNull) 2096 Diag(loc, diag::ext_typecheck_comparison_of_pointer_integer, 2097 lType.getAsString(), rType.getAsString(), 2098 lex->getSourceRange(), rex->getSourceRange()); 2099 ImpCastExprToType(rex, lType); // promote the integer to pointer 2100 return Context.IntTy; 2101 } 2102 if (lType->isIntegerType() && rType->isBlockPointerType()) { 2103 if (!LHSIsNull) 2104 Diag(loc, diag::ext_typecheck_comparison_of_pointer_integer, 2105 lType.getAsString(), rType.getAsString(), 2106 lex->getSourceRange(), rex->getSourceRange()); 2107 ImpCastExprToType(lex, rType); // promote the integer to pointer 2108 return Context.IntTy; 2109 } 2110 return InvalidOperands(loc, lex, rex); 2111} 2112 2113/// CheckVectorCompareOperands - vector comparisons are a clang extension that 2114/// operates on extended vector types. Instead of producing an IntTy result, 2115/// like a scalar comparison, a vector comparison produces a vector of integer 2116/// types. 2117QualType Sema::CheckVectorCompareOperands(Expr *&lex, Expr *&rex, 2118 SourceLocation loc, 2119 bool isRelational) { 2120 // Check to make sure we're operating on vectors of the same type and width, 2121 // Allowing one side to be a scalar of element type. 2122 QualType vType = CheckVectorOperands(loc, lex, rex); 2123 if (vType.isNull()) 2124 return vType; 2125 2126 QualType lType = lex->getType(); 2127 QualType rType = rex->getType(); 2128 2129 // For non-floating point types, check for self-comparisons of the form 2130 // x == x, x != x, x < x, etc. These always evaluate to a constant, and 2131 // often indicate logic errors in the program. 2132 if (!lType->isFloatingType()) { 2133 if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(lex->IgnoreParens())) 2134 if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(rex->IgnoreParens())) 2135 if (DRL->getDecl() == DRR->getDecl()) 2136 Diag(loc, diag::warn_selfcomparison); 2137 } 2138 2139 // Check for comparisons of floating point operands using != and ==. 2140 if (!isRelational && lType->isFloatingType()) { 2141 assert (rType->isFloatingType()); 2142 CheckFloatComparison(loc,lex,rex); 2143 } 2144 2145 // Return the type for the comparison, which is the same as vector type for 2146 // integer vectors, or an integer type of identical size and number of 2147 // elements for floating point vectors. 2148 if (lType->isIntegerType()) 2149 return lType; 2150 2151 const VectorType *VTy = lType->getAsVectorType(); 2152 2153 // FIXME: need to deal with non-32b int / non-64b long long 2154 unsigned TypeSize = Context.getTypeSize(VTy->getElementType()); 2155 if (TypeSize == 32) { 2156 return Context.getExtVectorType(Context.IntTy, VTy->getNumElements()); 2157 } 2158 assert(TypeSize == 64 && "Unhandled vector element size in vector compare"); 2159 return Context.getExtVectorType(Context.LongLongTy, VTy->getNumElements()); 2160} 2161 2162inline QualType Sema::CheckBitwiseOperands( 2163 Expr *&lex, Expr *&rex, SourceLocation loc, bool isCompAssign) 2164{ 2165 if (lex->getType()->isVectorType() || rex->getType()->isVectorType()) 2166 return CheckVectorOperands(loc, lex, rex); 2167 2168 QualType compType = UsualArithmeticConversions(lex, rex, isCompAssign); 2169 2170 if (lex->getType()->isIntegerType() && rex->getType()->isIntegerType()) 2171 return compType; 2172 return InvalidOperands(loc, lex, rex); 2173} 2174 2175inline QualType Sema::CheckLogicalOperands( // C99 6.5.[13,14] 2176 Expr *&lex, Expr *&rex, SourceLocation loc) 2177{ 2178 UsualUnaryConversions(lex); 2179 UsualUnaryConversions(rex); 2180 2181 if (lex->getType()->isScalarType() && rex->getType()->isScalarType()) 2182 return Context.IntTy; 2183 return InvalidOperands(loc, lex, rex); 2184} 2185 2186inline QualType Sema::CheckAssignmentOperands( // C99 6.5.16.1 2187 Expr *lex, Expr *&rex, SourceLocation loc, QualType compoundType) 2188{ 2189 QualType lhsType = lex->getType(); 2190 QualType rhsType = compoundType.isNull() ? rex->getType() : compoundType; 2191 Expr::isModifiableLvalueResult mlval = lex->isModifiableLvalue(Context); 2192 2193 switch (mlval) { // C99 6.5.16p2 2194 case Expr::MLV_Valid: 2195 break; 2196 case Expr::MLV_ConstQualified: 2197 Diag(loc, diag::err_typecheck_assign_const, lex->getSourceRange()); 2198 return QualType(); 2199 case Expr::MLV_ArrayType: 2200 Diag(loc, diag::err_typecheck_array_not_modifiable_lvalue, 2201 lhsType.getAsString(), lex->getSourceRange()); 2202 return QualType(); 2203 case Expr::MLV_NotObjectType: 2204 Diag(loc, diag::err_typecheck_non_object_not_modifiable_lvalue, 2205 lhsType.getAsString(), lex->getSourceRange()); 2206 return QualType(); 2207 case Expr::MLV_InvalidExpression: 2208 Diag(loc, diag::err_typecheck_expression_not_modifiable_lvalue, 2209 lex->getSourceRange()); 2210 return QualType(); 2211 case Expr::MLV_IncompleteType: 2212 case Expr::MLV_IncompleteVoidType: 2213 Diag(loc, diag::err_typecheck_incomplete_type_not_modifiable_lvalue, 2214 lhsType.getAsString(), lex->getSourceRange()); 2215 return QualType(); 2216 case Expr::MLV_DuplicateVectorComponents: 2217 Diag(loc, diag::err_typecheck_duplicate_vector_components_not_mlvalue, 2218 lex->getSourceRange()); 2219 return QualType(); 2220 case Expr::MLV_NotBlockQualified: 2221 Diag(loc, diag::err_block_decl_ref_not_modifiable_lvalue, 2222 lex->getSourceRange()); 2223 return QualType(); 2224 } 2225 2226 AssignConvertType ConvTy; 2227 if (compoundType.isNull()) { 2228 // Simple assignment "x = y". 2229 ConvTy = CheckSingleAssignmentConstraints(lhsType, rex); 2230 2231 // If the RHS is a unary plus or minus, check to see if they = and + are 2232 // right next to each other. If so, the user may have typo'd "x =+ 4" 2233 // instead of "x += 4". 2234 Expr *RHSCheck = rex; 2235 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(RHSCheck)) 2236 RHSCheck = ICE->getSubExpr(); 2237 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(RHSCheck)) { 2238 if ((UO->getOpcode() == UnaryOperator::Plus || 2239 UO->getOpcode() == UnaryOperator::Minus) && 2240 loc.isFileID() && UO->getOperatorLoc().isFileID() && 2241 // Only if the two operators are exactly adjacent. 2242 loc.getFileLocWithOffset(1) == UO->getOperatorLoc()) 2243 Diag(loc, diag::warn_not_compound_assign, 2244 UO->getOpcode() == UnaryOperator::Plus ? "+" : "-", 2245 SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc())); 2246 } 2247 } else { 2248 // Compound assignment "x += y" 2249 ConvTy = CheckCompoundAssignmentConstraints(lhsType, rhsType); 2250 } 2251 2252 if (DiagnoseAssignmentResult(ConvTy, loc, lhsType, rhsType, 2253 rex, "assigning")) 2254 return QualType(); 2255 2256 // C99 6.5.16p3: The type of an assignment expression is the type of the 2257 // left operand unless the left operand has qualified type, in which case 2258 // it is the unqualified version of the type of the left operand. 2259 // C99 6.5.16.1p2: In simple assignment, the value of the right operand 2260 // is converted to the type of the assignment expression (above). 2261 // C++ 5.17p1: the type of the assignment expression is that of its left 2262 // oprdu. 2263 return lhsType.getUnqualifiedType(); 2264} 2265 2266inline QualType Sema::CheckCommaOperands( // C99 6.5.17 2267 Expr *&lex, Expr *&rex, SourceLocation loc) { 2268 2269 // Comma performs lvalue conversion (C99 6.3.2.1), but not unary conversions. 2270 DefaultFunctionArrayConversion(rex); 2271 return rex->getType(); 2272} 2273 2274/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine 2275/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions. 2276QualType Sema::CheckIncrementDecrementOperand(Expr *op, SourceLocation OpLoc) { 2277 QualType resType = op->getType(); 2278 assert(!resType.isNull() && "no type for increment/decrement expression"); 2279 2280 // C99 6.5.2.4p1: We allow complex as a GCC extension. 2281 if (const PointerType *pt = resType->getAsPointerType()) { 2282 if (pt->getPointeeType()->isVoidType()) { 2283 Diag(OpLoc, diag::ext_gnu_void_ptr, op->getSourceRange()); 2284 } else if (!pt->getPointeeType()->isObjectType()) { 2285 // C99 6.5.2.4p2, 6.5.6p2 2286 Diag(OpLoc, diag::err_typecheck_arithmetic_incomplete_type, 2287 resType.getAsString(), op->getSourceRange()); 2288 return QualType(); 2289 } 2290 } else if (!resType->isRealType()) { 2291 if (resType->isComplexType()) 2292 // C99 does not support ++/-- on complex types. 2293 Diag(OpLoc, diag::ext_integer_increment_complex, 2294 resType.getAsString(), op->getSourceRange()); 2295 else { 2296 Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement, 2297 resType.getAsString(), op->getSourceRange()); 2298 return QualType(); 2299 } 2300 } 2301 // At this point, we know we have a real, complex or pointer type. 2302 // Now make sure the operand is a modifiable lvalue. 2303 Expr::isModifiableLvalueResult mlval = op->isModifiableLvalue(Context); 2304 if (mlval != Expr::MLV_Valid) { 2305 // FIXME: emit a more precise diagnostic... 2306 Diag(OpLoc, diag::err_typecheck_invalid_lvalue_incr_decr, 2307 op->getSourceRange()); 2308 return QualType(); 2309 } 2310 return resType; 2311} 2312 2313/// getPrimaryDecl - Helper function for CheckAddressOfOperand(). 2314/// This routine allows us to typecheck complex/recursive expressions 2315/// where the declaration is needed for type checking. We only need to 2316/// handle cases when the expression references a function designator 2317/// or is an lvalue. Here are some examples: 2318/// - &(x) => x 2319/// - &*****f => f for f a function designator. 2320/// - &s.xx => s 2321/// - &s.zz[1].yy -> s, if zz is an array 2322/// - *(x + 1) -> x, if x is an array 2323/// - &"123"[2] -> 0 2324/// - & __real__ x -> x 2325static ValueDecl *getPrimaryDecl(Expr *E) { 2326 switch (E->getStmtClass()) { 2327 case Stmt::DeclRefExprClass: 2328 return cast<DeclRefExpr>(E)->getDecl(); 2329 case Stmt::MemberExprClass: 2330 // Fields cannot be declared with a 'register' storage class. 2331 // &X->f is always ok, even if X is declared register. 2332 if (cast<MemberExpr>(E)->isArrow()) 2333 return 0; 2334 return getPrimaryDecl(cast<MemberExpr>(E)->getBase()); 2335 case Stmt::ArraySubscriptExprClass: { 2336 // &X[4] and &4[X] refers to X if X is not a pointer. 2337 2338 ValueDecl *VD = getPrimaryDecl(cast<ArraySubscriptExpr>(E)->getBase()); 2339 if (!VD || VD->getType()->isPointerType()) 2340 return 0; 2341 else 2342 return VD; 2343 } 2344 case Stmt::UnaryOperatorClass: { 2345 UnaryOperator *UO = cast<UnaryOperator>(E); 2346 2347 switch(UO->getOpcode()) { 2348 case UnaryOperator::Deref: { 2349 // *(X + 1) refers to X if X is not a pointer. 2350 ValueDecl *VD = getPrimaryDecl(UO->getSubExpr()); 2351 if (!VD || VD->getType()->isPointerType()) 2352 return 0; 2353 return VD; 2354 } 2355 case UnaryOperator::Real: 2356 case UnaryOperator::Imag: 2357 case UnaryOperator::Extension: 2358 return getPrimaryDecl(UO->getSubExpr()); 2359 default: 2360 return 0; 2361 } 2362 } 2363 case Stmt::BinaryOperatorClass: { 2364 BinaryOperator *BO = cast<BinaryOperator>(E); 2365 2366 // Handle cases involving pointer arithmetic. The result of an 2367 // Assign or AddAssign is not an lvalue so they can be ignored. 2368 2369 // (x + n) or (n + x) => x 2370 if (BO->getOpcode() == BinaryOperator::Add) { 2371 if (BO->getLHS()->getType()->isPointerType()) { 2372 return getPrimaryDecl(BO->getLHS()); 2373 } else if (BO->getRHS()->getType()->isPointerType()) { 2374 return getPrimaryDecl(BO->getRHS()); 2375 } 2376 } 2377 2378 return 0; 2379 } 2380 case Stmt::ParenExprClass: 2381 return getPrimaryDecl(cast<ParenExpr>(E)->getSubExpr()); 2382 case Stmt::ImplicitCastExprClass: 2383 // &X[4] when X is an array, has an implicit cast from array to pointer. 2384 return getPrimaryDecl(cast<ImplicitCastExpr>(E)->getSubExpr()); 2385 default: 2386 return 0; 2387 } 2388} 2389 2390/// CheckAddressOfOperand - The operand of & must be either a function 2391/// designator or an lvalue designating an object. If it is an lvalue, the 2392/// object cannot be declared with storage class register or be a bit field. 2393/// Note: The usual conversions are *not* applied to the operand of the & 2394/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue. 2395QualType Sema::CheckAddressOfOperand(Expr *op, SourceLocation OpLoc) { 2396 if (getLangOptions().C99) { 2397 // Implement C99-only parts of addressof rules. 2398 if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(op)) { 2399 if (uOp->getOpcode() == UnaryOperator::Deref) 2400 // Per C99 6.5.3.2, the address of a deref always returns a valid result 2401 // (assuming the deref expression is valid). 2402 return uOp->getSubExpr()->getType(); 2403 } 2404 // Technically, there should be a check for array subscript 2405 // expressions here, but the result of one is always an lvalue anyway. 2406 } 2407 ValueDecl *dcl = getPrimaryDecl(op); 2408 Expr::isLvalueResult lval = op->isLvalue(Context); 2409 2410 if (lval != Expr::LV_Valid) { // C99 6.5.3.2p1 2411 if (!dcl || !isa<FunctionDecl>(dcl)) {// allow function designators 2412 // FIXME: emit more specific diag... 2413 Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof, 2414 op->getSourceRange()); 2415 return QualType(); 2416 } 2417 } else if (MemberExpr *MemExpr = dyn_cast<MemberExpr>(op)) { // C99 6.5.3.2p1 2418 if (MemExpr->getMemberDecl()->isBitField()) { 2419 Diag(OpLoc, diag::err_typecheck_address_of, 2420 std::string("bit-field"), op->getSourceRange()); 2421 return QualType(); 2422 } 2423 // Check for Apple extension for accessing vector components. 2424 } else if (isa<ArraySubscriptExpr>(op) && 2425 cast<ArraySubscriptExpr>(op)->getBase()->getType()->isVectorType()) { 2426 Diag(OpLoc, diag::err_typecheck_address_of, 2427 std::string("vector"), op->getSourceRange()); 2428 return QualType(); 2429 } else if (dcl) { // C99 6.5.3.2p1 2430 // We have an lvalue with a decl. Make sure the decl is not declared 2431 // with the register storage-class specifier. 2432 if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) { 2433 if (vd->getStorageClass() == VarDecl::Register) { 2434 Diag(OpLoc, diag::err_typecheck_address_of, 2435 std::string("register variable"), op->getSourceRange()); 2436 return QualType(); 2437 } 2438 } else 2439 assert(0 && "Unknown/unexpected decl type"); 2440 } 2441 2442 // If the operand has type "type", the result has type "pointer to type". 2443 return Context.getPointerType(op->getType()); 2444} 2445 2446QualType Sema::CheckIndirectionOperand(Expr *op, SourceLocation OpLoc) { 2447 UsualUnaryConversions(op); 2448 QualType qType = op->getType(); 2449 2450 if (const PointerType *PT = qType->getAsPointerType()) { 2451 // Note that per both C89 and C99, this is always legal, even 2452 // if ptype is an incomplete type or void. 2453 // It would be possible to warn about dereferencing a 2454 // void pointer, but it's completely well-defined, 2455 // and such a warning is unlikely to catch any mistakes. 2456 return PT->getPointeeType(); 2457 } 2458 Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer, 2459 qType.getAsString(), op->getSourceRange()); 2460 return QualType(); 2461} 2462 2463static inline BinaryOperator::Opcode ConvertTokenKindToBinaryOpcode( 2464 tok::TokenKind Kind) { 2465 BinaryOperator::Opcode Opc; 2466 switch (Kind) { 2467 default: assert(0 && "Unknown binop!"); 2468 case tok::star: Opc = BinaryOperator::Mul; break; 2469 case tok::slash: Opc = BinaryOperator::Div; break; 2470 case tok::percent: Opc = BinaryOperator::Rem; break; 2471 case tok::plus: Opc = BinaryOperator::Add; break; 2472 case tok::minus: Opc = BinaryOperator::Sub; break; 2473 case tok::lessless: Opc = BinaryOperator::Shl; break; 2474 case tok::greatergreater: Opc = BinaryOperator::Shr; break; 2475 case tok::lessequal: Opc = BinaryOperator::LE; break; 2476 case tok::less: Opc = BinaryOperator::LT; break; 2477 case tok::greaterequal: Opc = BinaryOperator::GE; break; 2478 case tok::greater: Opc = BinaryOperator::GT; break; 2479 case tok::exclaimequal: Opc = BinaryOperator::NE; break; 2480 case tok::equalequal: Opc = BinaryOperator::EQ; break; 2481 case tok::amp: Opc = BinaryOperator::And; break; 2482 case tok::caret: Opc = BinaryOperator::Xor; break; 2483 case tok::pipe: Opc = BinaryOperator::Or; break; 2484 case tok::ampamp: Opc = BinaryOperator::LAnd; break; 2485 case tok::pipepipe: Opc = BinaryOperator::LOr; break; 2486 case tok::equal: Opc = BinaryOperator::Assign; break; 2487 case tok::starequal: Opc = BinaryOperator::MulAssign; break; 2488 case tok::slashequal: Opc = BinaryOperator::DivAssign; break; 2489 case tok::percentequal: Opc = BinaryOperator::RemAssign; break; 2490 case tok::plusequal: Opc = BinaryOperator::AddAssign; break; 2491 case tok::minusequal: Opc = BinaryOperator::SubAssign; break; 2492 case tok::lesslessequal: Opc = BinaryOperator::ShlAssign; break; 2493 case tok::greatergreaterequal: Opc = BinaryOperator::ShrAssign; break; 2494 case tok::ampequal: Opc = BinaryOperator::AndAssign; break; 2495 case tok::caretequal: Opc = BinaryOperator::XorAssign; break; 2496 case tok::pipeequal: Opc = BinaryOperator::OrAssign; break; 2497 case tok::comma: Opc = BinaryOperator::Comma; break; 2498 } 2499 return Opc; 2500} 2501 2502static inline UnaryOperator::Opcode ConvertTokenKindToUnaryOpcode( 2503 tok::TokenKind Kind) { 2504 UnaryOperator::Opcode Opc; 2505 switch (Kind) { 2506 default: assert(0 && "Unknown unary op!"); 2507 case tok::plusplus: Opc = UnaryOperator::PreInc; break; 2508 case tok::minusminus: Opc = UnaryOperator::PreDec; break; 2509 case tok::amp: Opc = UnaryOperator::AddrOf; break; 2510 case tok::star: Opc = UnaryOperator::Deref; break; 2511 case tok::plus: Opc = UnaryOperator::Plus; break; 2512 case tok::minus: Opc = UnaryOperator::Minus; break; 2513 case tok::tilde: Opc = UnaryOperator::Not; break; 2514 case tok::exclaim: Opc = UnaryOperator::LNot; break; 2515 case tok::kw_sizeof: Opc = UnaryOperator::SizeOf; break; 2516 case tok::kw___alignof: Opc = UnaryOperator::AlignOf; break; 2517 case tok::kw___real: Opc = UnaryOperator::Real; break; 2518 case tok::kw___imag: Opc = UnaryOperator::Imag; break; 2519 case tok::kw___extension__: Opc = UnaryOperator::Extension; break; 2520 } 2521 return Opc; 2522} 2523 2524// Binary Operators. 'Tok' is the token for the operator. 2525Action::ExprResult Sema::ActOnBinOp(SourceLocation TokLoc, tok::TokenKind Kind, 2526 ExprTy *LHS, ExprTy *RHS) { 2527 BinaryOperator::Opcode Opc = ConvertTokenKindToBinaryOpcode(Kind); 2528 Expr *lhs = (Expr *)LHS, *rhs = (Expr*)RHS; 2529 2530 assert((lhs != 0) && "ActOnBinOp(): missing left expression"); 2531 assert((rhs != 0) && "ActOnBinOp(): missing right expression"); 2532 2533 QualType ResultTy; // Result type of the binary operator. 2534 QualType CompTy; // Computation type for compound assignments (e.g. '+=') 2535 2536 switch (Opc) { 2537 default: 2538 assert(0 && "Unknown binary expr!"); 2539 case BinaryOperator::Assign: 2540 ResultTy = CheckAssignmentOperands(lhs, rhs, TokLoc, QualType()); 2541 break; 2542 case BinaryOperator::Mul: 2543 case BinaryOperator::Div: 2544 ResultTy = CheckMultiplyDivideOperands(lhs, rhs, TokLoc); 2545 break; 2546 case BinaryOperator::Rem: 2547 ResultTy = CheckRemainderOperands(lhs, rhs, TokLoc); 2548 break; 2549 case BinaryOperator::Add: 2550 ResultTy = CheckAdditionOperands(lhs, rhs, TokLoc); 2551 break; 2552 case BinaryOperator::Sub: 2553 ResultTy = CheckSubtractionOperands(lhs, rhs, TokLoc); 2554 break; 2555 case BinaryOperator::Shl: 2556 case BinaryOperator::Shr: 2557 ResultTy = CheckShiftOperands(lhs, rhs, TokLoc); 2558 break; 2559 case BinaryOperator::LE: 2560 case BinaryOperator::LT: 2561 case BinaryOperator::GE: 2562 case BinaryOperator::GT: 2563 ResultTy = CheckCompareOperands(lhs, rhs, TokLoc, true); 2564 break; 2565 case BinaryOperator::EQ: 2566 case BinaryOperator::NE: 2567 ResultTy = CheckCompareOperands(lhs, rhs, TokLoc, false); 2568 break; 2569 case BinaryOperator::And: 2570 case BinaryOperator::Xor: 2571 case BinaryOperator::Or: 2572 ResultTy = CheckBitwiseOperands(lhs, rhs, TokLoc); 2573 break; 2574 case BinaryOperator::LAnd: 2575 case BinaryOperator::LOr: 2576 ResultTy = CheckLogicalOperands(lhs, rhs, TokLoc); 2577 break; 2578 case BinaryOperator::MulAssign: 2579 case BinaryOperator::DivAssign: 2580 CompTy = CheckMultiplyDivideOperands(lhs, rhs, TokLoc, true); 2581 if (!CompTy.isNull()) 2582 ResultTy = CheckAssignmentOperands(lhs, rhs, TokLoc, CompTy); 2583 break; 2584 case BinaryOperator::RemAssign: 2585 CompTy = CheckRemainderOperands(lhs, rhs, TokLoc, true); 2586 if (!CompTy.isNull()) 2587 ResultTy = CheckAssignmentOperands(lhs, rhs, TokLoc, CompTy); 2588 break; 2589 case BinaryOperator::AddAssign: 2590 CompTy = CheckAdditionOperands(lhs, rhs, TokLoc, true); 2591 if (!CompTy.isNull()) 2592 ResultTy = CheckAssignmentOperands(lhs, rhs, TokLoc, CompTy); 2593 break; 2594 case BinaryOperator::SubAssign: 2595 CompTy = CheckSubtractionOperands(lhs, rhs, TokLoc, true); 2596 if (!CompTy.isNull()) 2597 ResultTy = CheckAssignmentOperands(lhs, rhs, TokLoc, CompTy); 2598 break; 2599 case BinaryOperator::ShlAssign: 2600 case BinaryOperator::ShrAssign: 2601 CompTy = CheckShiftOperands(lhs, rhs, TokLoc, true); 2602 if (!CompTy.isNull()) 2603 ResultTy = CheckAssignmentOperands(lhs, rhs, TokLoc, CompTy); 2604 break; 2605 case BinaryOperator::AndAssign: 2606 case BinaryOperator::XorAssign: 2607 case BinaryOperator::OrAssign: 2608 CompTy = CheckBitwiseOperands(lhs, rhs, TokLoc, true); 2609 if (!CompTy.isNull()) 2610 ResultTy = CheckAssignmentOperands(lhs, rhs, TokLoc, CompTy); 2611 break; 2612 case BinaryOperator::Comma: 2613 ResultTy = CheckCommaOperands(lhs, rhs, TokLoc); 2614 break; 2615 } 2616 if (ResultTy.isNull()) 2617 return true; 2618 if (CompTy.isNull()) 2619 return new BinaryOperator(lhs, rhs, Opc, ResultTy, TokLoc); 2620 else 2621 return new CompoundAssignOperator(lhs, rhs, Opc, ResultTy, CompTy, TokLoc); 2622} 2623 2624// Unary Operators. 'Tok' is the token for the operator. 2625Action::ExprResult Sema::ActOnUnaryOp(SourceLocation OpLoc, tok::TokenKind Op, 2626 ExprTy *input) { 2627 Expr *Input = (Expr*)input; 2628 UnaryOperator::Opcode Opc = ConvertTokenKindToUnaryOpcode(Op); 2629 QualType resultType; 2630 switch (Opc) { 2631 default: 2632 assert(0 && "Unimplemented unary expr!"); 2633 case UnaryOperator::PreInc: 2634 case UnaryOperator::PreDec: 2635 resultType = CheckIncrementDecrementOperand(Input, OpLoc); 2636 break; 2637 case UnaryOperator::AddrOf: 2638 resultType = CheckAddressOfOperand(Input, OpLoc); 2639 break; 2640 case UnaryOperator::Deref: 2641 DefaultFunctionArrayConversion(Input); 2642 resultType = CheckIndirectionOperand(Input, OpLoc); 2643 break; 2644 case UnaryOperator::Plus: 2645 case UnaryOperator::Minus: 2646 UsualUnaryConversions(Input); 2647 resultType = Input->getType(); 2648 if (!resultType->isArithmeticType()) // C99 6.5.3.3p1 2649 return Diag(OpLoc, diag::err_typecheck_unary_expr, 2650 resultType.getAsString()); 2651 break; 2652 case UnaryOperator::Not: // bitwise complement 2653 UsualUnaryConversions(Input); 2654 resultType = Input->getType(); 2655 // C99 6.5.3.3p1. We allow complex int and float as a GCC extension. 2656 if (resultType->isComplexType() || resultType->isComplexIntegerType()) 2657 // C99 does not support '~' for complex conjugation. 2658 Diag(OpLoc, diag::ext_integer_complement_complex, 2659 resultType.getAsString(), Input->getSourceRange()); 2660 else if (!resultType->isIntegerType()) 2661 return Diag(OpLoc, diag::err_typecheck_unary_expr, 2662 resultType.getAsString(), Input->getSourceRange()); 2663 break; 2664 case UnaryOperator::LNot: // logical negation 2665 // Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5). 2666 DefaultFunctionArrayConversion(Input); 2667 resultType = Input->getType(); 2668 if (!resultType->isScalarType()) // C99 6.5.3.3p1 2669 return Diag(OpLoc, diag::err_typecheck_unary_expr, 2670 resultType.getAsString()); 2671 // LNot always has type int. C99 6.5.3.3p5. 2672 resultType = Context.IntTy; 2673 break; 2674 case UnaryOperator::SizeOf: 2675 resultType = CheckSizeOfAlignOfOperand(Input->getType(), OpLoc, 2676 Input->getSourceRange(), true); 2677 break; 2678 case UnaryOperator::AlignOf: 2679 resultType = CheckSizeOfAlignOfOperand(Input->getType(), OpLoc, 2680 Input->getSourceRange(), false); 2681 break; 2682 case UnaryOperator::Real: 2683 case UnaryOperator::Imag: 2684 resultType = CheckRealImagOperand(Input, OpLoc); 2685 break; 2686 case UnaryOperator::Extension: 2687 resultType = Input->getType(); 2688 break; 2689 } 2690 if (resultType.isNull()) 2691 return true; 2692 return new UnaryOperator(Input, Opc, resultType, OpLoc); 2693} 2694 2695/// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo". 2696Sema::ExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, 2697 SourceLocation LabLoc, 2698 IdentifierInfo *LabelII) { 2699 // Look up the record for this label identifier. 2700 LabelStmt *&LabelDecl = LabelMap[LabelII]; 2701 2702 // If we haven't seen this label yet, create a forward reference. It 2703 // will be validated and/or cleaned up in ActOnFinishFunctionBody. 2704 if (LabelDecl == 0) 2705 LabelDecl = new LabelStmt(LabLoc, LabelII, 0); 2706 2707 // Create the AST node. The address of a label always has type 'void*'. 2708 return new AddrLabelExpr(OpLoc, LabLoc, LabelDecl, 2709 Context.getPointerType(Context.VoidTy)); 2710} 2711 2712Sema::ExprResult Sema::ActOnStmtExpr(SourceLocation LPLoc, StmtTy *substmt, 2713 SourceLocation RPLoc) { // "({..})" 2714 Stmt *SubStmt = static_cast<Stmt*>(substmt); 2715 assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!"); 2716 CompoundStmt *Compound = cast<CompoundStmt>(SubStmt); 2717 2718 // FIXME: there are a variety of strange constraints to enforce here, for 2719 // example, it is not possible to goto into a stmt expression apparently. 2720 // More semantic analysis is needed. 2721 2722 // FIXME: the last statement in the compount stmt has its value used. We 2723 // should not warn about it being unused. 2724 2725 // If there are sub stmts in the compound stmt, take the type of the last one 2726 // as the type of the stmtexpr. 2727 QualType Ty = Context.VoidTy; 2728 2729 if (!Compound->body_empty()) { 2730 Stmt *LastStmt = Compound->body_back(); 2731 // If LastStmt is a label, skip down through into the body. 2732 while (LabelStmt *Label = dyn_cast<LabelStmt>(LastStmt)) 2733 LastStmt = Label->getSubStmt(); 2734 2735 if (Expr *LastExpr = dyn_cast<Expr>(LastStmt)) 2736 Ty = LastExpr->getType(); 2737 } 2738 2739 return new StmtExpr(Compound, Ty, LPLoc, RPLoc); 2740} 2741 2742Sema::ExprResult Sema::ActOnBuiltinOffsetOf(SourceLocation BuiltinLoc, 2743 SourceLocation TypeLoc, 2744 TypeTy *argty, 2745 OffsetOfComponent *CompPtr, 2746 unsigned NumComponents, 2747 SourceLocation RPLoc) { 2748 QualType ArgTy = QualType::getFromOpaquePtr(argty); 2749 assert(!ArgTy.isNull() && "Missing type argument!"); 2750 2751 // We must have at least one component that refers to the type, and the first 2752 // one is known to be a field designator. Verify that the ArgTy represents 2753 // a struct/union/class. 2754 if (!ArgTy->isRecordType()) 2755 return Diag(TypeLoc, diag::err_offsetof_record_type,ArgTy.getAsString()); 2756 2757 // Otherwise, create a compound literal expression as the base, and 2758 // iteratively process the offsetof designators. 2759 Expr *Res = new CompoundLiteralExpr(SourceLocation(), ArgTy, 0, false); 2760 2761 // offsetof with non-identifier designators (e.g. "offsetof(x, a.b[c])") are a 2762 // GCC extension, diagnose them. 2763 if (NumComponents != 1) 2764 Diag(BuiltinLoc, diag::ext_offsetof_extended_field_designator, 2765 SourceRange(CompPtr[1].LocStart, CompPtr[NumComponents-1].LocEnd)); 2766 2767 for (unsigned i = 0; i != NumComponents; ++i) { 2768 const OffsetOfComponent &OC = CompPtr[i]; 2769 if (OC.isBrackets) { 2770 // Offset of an array sub-field. TODO: Should we allow vector elements? 2771 const ArrayType *AT = Context.getAsArrayType(Res->getType()); 2772 if (!AT) { 2773 delete Res; 2774 return Diag(OC.LocEnd, diag::err_offsetof_array_type, 2775 Res->getType().getAsString()); 2776 } 2777 2778 // FIXME: C++: Verify that operator[] isn't overloaded. 2779 2780 // C99 6.5.2.1p1 2781 Expr *Idx = static_cast<Expr*>(OC.U.E); 2782 if (!Idx->getType()->isIntegerType()) 2783 return Diag(Idx->getLocStart(), diag::err_typecheck_subscript, 2784 Idx->getSourceRange()); 2785 2786 Res = new ArraySubscriptExpr(Res, Idx, AT->getElementType(), OC.LocEnd); 2787 continue; 2788 } 2789 2790 const RecordType *RC = Res->getType()->getAsRecordType(); 2791 if (!RC) { 2792 delete Res; 2793 return Diag(OC.LocEnd, diag::err_offsetof_record_type, 2794 Res->getType().getAsString()); 2795 } 2796 2797 // Get the decl corresponding to this. 2798 RecordDecl *RD = RC->getDecl(); 2799 FieldDecl *MemberDecl = RD->getMember(OC.U.IdentInfo); 2800 if (!MemberDecl) 2801 return Diag(BuiltinLoc, diag::err_typecheck_no_member, 2802 OC.U.IdentInfo->getName(), 2803 SourceRange(OC.LocStart, OC.LocEnd)); 2804 2805 // FIXME: C++: Verify that MemberDecl isn't a static field. 2806 // FIXME: Verify that MemberDecl isn't a bitfield. 2807 // MemberDecl->getType() doesn't get the right qualifiers, but it doesn't 2808 // matter here. 2809 Res = new MemberExpr(Res, false, MemberDecl, OC.LocEnd, MemberDecl->getType()); 2810 } 2811 2812 return new UnaryOperator(Res, UnaryOperator::OffsetOf, Context.getSizeType(), 2813 BuiltinLoc); 2814} 2815 2816 2817Sema::ExprResult Sema::ActOnTypesCompatibleExpr(SourceLocation BuiltinLoc, 2818 TypeTy *arg1, TypeTy *arg2, 2819 SourceLocation RPLoc) { 2820 QualType argT1 = QualType::getFromOpaquePtr(arg1); 2821 QualType argT2 = QualType::getFromOpaquePtr(arg2); 2822 2823 assert((!argT1.isNull() && !argT2.isNull()) && "Missing type argument(s)"); 2824 2825 return new TypesCompatibleExpr(Context.IntTy, BuiltinLoc, argT1, argT2,RPLoc); 2826} 2827 2828Sema::ExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc, ExprTy *cond, 2829 ExprTy *expr1, ExprTy *expr2, 2830 SourceLocation RPLoc) { 2831 Expr *CondExpr = static_cast<Expr*>(cond); 2832 Expr *LHSExpr = static_cast<Expr*>(expr1); 2833 Expr *RHSExpr = static_cast<Expr*>(expr2); 2834 2835 assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)"); 2836 2837 // The conditional expression is required to be a constant expression. 2838 llvm::APSInt condEval(32); 2839 SourceLocation ExpLoc; 2840 if (!CondExpr->isIntegerConstantExpr(condEval, Context, &ExpLoc)) 2841 return Diag(ExpLoc, diag::err_typecheck_choose_expr_requires_constant, 2842 CondExpr->getSourceRange()); 2843 2844 // If the condition is > zero, then the AST type is the same as the LSHExpr. 2845 QualType resType = condEval.getZExtValue() ? LHSExpr->getType() : 2846 RHSExpr->getType(); 2847 return new ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, resType, RPLoc); 2848} 2849 2850//===----------------------------------------------------------------------===// 2851// Clang Extensions. 2852//===----------------------------------------------------------------------===// 2853 2854/// ActOnBlockStart - This callback is invoked when a block literal is started. 2855void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *BlockScope, 2856 Declarator &ParamInfo) { 2857 // Analyze block parameters. 2858 BlockSemaInfo *BSI = new BlockSemaInfo(); 2859 2860 // Add BSI to CurBlock. 2861 BSI->PrevBlockInfo = CurBlock; 2862 CurBlock = BSI; 2863 2864 BSI->ReturnType = 0; 2865 BSI->TheScope = BlockScope; 2866 2867 // Analyze arguments to block. 2868 assert(ParamInfo.getTypeObject(0).Kind == DeclaratorChunk::Function && 2869 "Not a function declarator!"); 2870 DeclaratorChunk::FunctionTypeInfo &FTI = ParamInfo.getTypeObject(0).Fun; 2871 2872 BSI->hasPrototype = FTI.hasPrototype; 2873 BSI->isVariadic = true; 2874 2875 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs function that takes 2876 // no arguments, not a function that takes a single void argument. 2877 if (FTI.hasPrototype && 2878 FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2879 (!((ParmVarDecl *)FTI.ArgInfo[0].Param)->getType().getCVRQualifiers() && 2880 ((ParmVarDecl *)FTI.ArgInfo[0].Param)->getType()->isVoidType())) { 2881 // empty arg list, don't push any params. 2882 BSI->isVariadic = false; 2883 } else if (FTI.hasPrototype) { 2884 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 2885 BSI->Params.push_back((ParmVarDecl *)FTI.ArgInfo[i].Param); 2886 BSI->isVariadic = FTI.isVariadic; 2887 } 2888} 2889 2890/// ActOnBlockError - If there is an error parsing a block, this callback 2891/// is invoked to pop the information about the block from the action impl. 2892void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) { 2893 // Ensure that CurBlock is deleted. 2894 llvm::OwningPtr<BlockSemaInfo> CC(CurBlock); 2895 2896 // Pop off CurBlock, handle nested blocks. 2897 CurBlock = CurBlock->PrevBlockInfo; 2898 2899 // FIXME: Delete the ParmVarDecl objects as well??? 2900 2901} 2902 2903/// ActOnBlockStmtExpr - This is called when the body of a block statement 2904/// literal was successfully completed. ^(int x){...} 2905Sema::ExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc, StmtTy *body, 2906 Scope *CurScope) { 2907 // Ensure that CurBlock is deleted. 2908 llvm::OwningPtr<BlockSemaInfo> BSI(CurBlock); 2909 llvm::OwningPtr<CompoundStmt> Body(static_cast<CompoundStmt*>(body)); 2910 2911 // Pop off CurBlock, handle nested blocks. 2912 CurBlock = CurBlock->PrevBlockInfo; 2913 2914 QualType RetTy = Context.VoidTy; 2915 if (BSI->ReturnType) 2916 RetTy = QualType(BSI->ReturnType, 0); 2917 2918 llvm::SmallVector<QualType, 8> ArgTypes; 2919 for (unsigned i = 0, e = BSI->Params.size(); i != e; ++i) 2920 ArgTypes.push_back(BSI->Params[i]->getType()); 2921 2922 QualType BlockTy; 2923 if (!BSI->hasPrototype) 2924 BlockTy = Context.getFunctionTypeNoProto(RetTy); 2925 else 2926 BlockTy = Context.getFunctionType(RetTy, &ArgTypes[0], ArgTypes.size(), 2927 BSI->isVariadic); 2928 2929 BlockTy = Context.getBlockPointerType(BlockTy); 2930 return new BlockExpr(CaretLoc, BlockTy, &BSI->Params[0], BSI->Params.size(), 2931 Body.take()); 2932} 2933 2934/// ExprsMatchFnType - return true if the Exprs in array Args have 2935/// QualTypes that match the QualTypes of the arguments of the FnType. 2936/// The number of arguments has already been validated to match the number of 2937/// arguments in FnType. 2938static bool ExprsMatchFnType(Expr **Args, const FunctionTypeProto *FnType, 2939 ASTContext &Context) { 2940 unsigned NumParams = FnType->getNumArgs(); 2941 for (unsigned i = 0; i != NumParams; ++i) { 2942 QualType ExprTy = Context.getCanonicalType(Args[i]->getType()); 2943 QualType ParmTy = Context.getCanonicalType(FnType->getArgType(i)); 2944 2945 if (ExprTy.getUnqualifiedType() != ParmTy.getUnqualifiedType()) 2946 return false; 2947 } 2948 return true; 2949} 2950 2951Sema::ExprResult Sema::ActOnOverloadExpr(ExprTy **args, unsigned NumArgs, 2952 SourceLocation *CommaLocs, 2953 SourceLocation BuiltinLoc, 2954 SourceLocation RParenLoc) { 2955 // __builtin_overload requires at least 2 arguments 2956 if (NumArgs < 2) 2957 return Diag(RParenLoc, diag::err_typecheck_call_too_few_args, 2958 SourceRange(BuiltinLoc, RParenLoc)); 2959 2960 // The first argument is required to be a constant expression. It tells us 2961 // the number of arguments to pass to each of the functions to be overloaded. 2962 Expr **Args = reinterpret_cast<Expr**>(args); 2963 Expr *NParamsExpr = Args[0]; 2964 llvm::APSInt constEval(32); 2965 SourceLocation ExpLoc; 2966 if (!NParamsExpr->isIntegerConstantExpr(constEval, Context, &ExpLoc)) 2967 return Diag(ExpLoc, diag::err_overload_expr_requires_non_zero_constant, 2968 NParamsExpr->getSourceRange()); 2969 2970 // Verify that the number of parameters is > 0 2971 unsigned NumParams = constEval.getZExtValue(); 2972 if (NumParams == 0) 2973 return Diag(ExpLoc, diag::err_overload_expr_requires_non_zero_constant, 2974 NParamsExpr->getSourceRange()); 2975 // Verify that we have at least 1 + NumParams arguments to the builtin. 2976 if ((NumParams + 1) > NumArgs) 2977 return Diag(RParenLoc, diag::err_typecheck_call_too_few_args, 2978 SourceRange(BuiltinLoc, RParenLoc)); 2979 2980 // Figure out the return type, by matching the args to one of the functions 2981 // listed after the parameters. 2982 OverloadExpr *OE = 0; 2983 for (unsigned i = NumParams + 1; i < NumArgs; ++i) { 2984 // UsualUnaryConversions will convert the function DeclRefExpr into a 2985 // pointer to function. 2986 Expr *Fn = UsualUnaryConversions(Args[i]); 2987 const FunctionTypeProto *FnType = 0; 2988 if (const PointerType *PT = Fn->getType()->getAsPointerType()) 2989 FnType = PT->getPointeeType()->getAsFunctionTypeProto(); 2990 2991 // The Expr type must be FunctionTypeProto, since FunctionTypeProto has no 2992 // parameters, and the number of parameters must match the value passed to 2993 // the builtin. 2994 if (!FnType || (FnType->getNumArgs() != NumParams)) 2995 return Diag(Fn->getExprLoc(), diag::err_overload_incorrect_fntype, 2996 Fn->getSourceRange()); 2997 2998 // Scan the parameter list for the FunctionType, checking the QualType of 2999 // each parameter against the QualTypes of the arguments to the builtin. 3000 // If they match, return a new OverloadExpr. 3001 if (ExprsMatchFnType(Args+1, FnType, Context)) { 3002 if (OE) 3003 return Diag(Fn->getExprLoc(), diag::err_overload_multiple_match, 3004 OE->getFn()->getSourceRange()); 3005 // Remember our match, and continue processing the remaining arguments 3006 // to catch any errors. 3007 OE = new OverloadExpr(Args, NumArgs, i, FnType->getResultType(), 3008 BuiltinLoc, RParenLoc); 3009 } 3010 } 3011 // Return the newly created OverloadExpr node, if we succeded in matching 3012 // exactly one of the candidate functions. 3013 if (OE) 3014 return OE; 3015 3016 // If we didn't find a matching function Expr in the __builtin_overload list 3017 // the return an error. 3018 std::string typeNames; 3019 for (unsigned i = 0; i != NumParams; ++i) { 3020 if (i != 0) typeNames += ", "; 3021 typeNames += Args[i+1]->getType().getAsString(); 3022 } 3023 3024 return Diag(BuiltinLoc, diag::err_overload_no_match, typeNames, 3025 SourceRange(BuiltinLoc, RParenLoc)); 3026} 3027 3028Sema::ExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, 3029 ExprTy *expr, TypeTy *type, 3030 SourceLocation RPLoc) { 3031 Expr *E = static_cast<Expr*>(expr); 3032 QualType T = QualType::getFromOpaquePtr(type); 3033 3034 InitBuiltinVaListType(); 3035 3036 // Get the va_list type 3037 QualType VaListType = Context.getBuiltinVaListType(); 3038 // Deal with implicit array decay; for example, on x86-64, 3039 // va_list is an array, but it's supposed to decay to 3040 // a pointer for va_arg. 3041 if (VaListType->isArrayType()) 3042 VaListType = Context.getArrayDecayedType(VaListType); 3043 // Make sure the input expression also decays appropriately. 3044 UsualUnaryConversions(E); 3045 3046 if (CheckAssignmentConstraints(VaListType, E->getType()) != Compatible) 3047 return Diag(E->getLocStart(), 3048 diag::err_first_argument_to_va_arg_not_of_type_va_list, 3049 E->getType().getAsString(), 3050 E->getSourceRange()); 3051 3052 // FIXME: Warn if a non-POD type is passed in. 3053 3054 return new VAArgExpr(BuiltinLoc, E, T, RPLoc); 3055} 3056 3057bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy, 3058 SourceLocation Loc, 3059 QualType DstType, QualType SrcType, 3060 Expr *SrcExpr, const char *Flavor) { 3061 // Decode the result (notice that AST's are still created for extensions). 3062 bool isInvalid = false; 3063 unsigned DiagKind; 3064 switch (ConvTy) { 3065 default: assert(0 && "Unknown conversion type"); 3066 case Compatible: return false; 3067 case PointerToInt: 3068 DiagKind = diag::ext_typecheck_convert_pointer_int; 3069 break; 3070 case IntToPointer: 3071 DiagKind = diag::ext_typecheck_convert_int_pointer; 3072 break; 3073 case IncompatiblePointer: 3074 DiagKind = diag::ext_typecheck_convert_incompatible_pointer; 3075 break; 3076 case FunctionVoidPointer: 3077 DiagKind = diag::ext_typecheck_convert_pointer_void_func; 3078 break; 3079 case CompatiblePointerDiscardsQualifiers: 3080 // If the qualifiers lost were because we were applying the 3081 // (deprecated) C++ conversion from a string literal to a char* 3082 // (or wchar_t*), then there was no error (C++ 4.2p2). FIXME: 3083 // Ideally, this check would be performed in 3084 // CheckPointerTypesForAssignment. However, that would require a 3085 // bit of refactoring (so that the second argument is an 3086 // expression, rather than a type), which should be done as part 3087 // of a larger effort to fix CheckPointerTypesForAssignment for 3088 // C++ semantics. 3089 if (getLangOptions().CPlusPlus && 3090 IsStringLiteralToNonConstPointerConversion(SrcExpr, DstType)) 3091 return false; 3092 DiagKind = diag::ext_typecheck_convert_discards_qualifiers; 3093 break; 3094 case IntToBlockPointer: 3095 DiagKind = diag::err_int_to_block_pointer; 3096 break; 3097 case IncompatibleBlockPointer: 3098 DiagKind = diag::ext_typecheck_convert_incompatible_block_pointer; 3099 break; 3100 case BlockVoidPointer: 3101 DiagKind = diag::ext_typecheck_convert_pointer_void_block; 3102 break; 3103 case Incompatible: 3104 DiagKind = diag::err_typecheck_convert_incompatible; 3105 isInvalid = true; 3106 break; 3107 } 3108 3109 Diag(Loc, DiagKind, DstType.getAsString(), SrcType.getAsString(), Flavor, 3110 SrcExpr->getSourceRange()); 3111 return isInvalid; 3112} 3113