ParseExpr.cpp revision efaa93aaa2653f4eb40e6a22e504a448da94aaf8
1//===--- ParseExpr.cpp - Expression Parsing -------------------------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements the Expression parsing implementation. Expressions in 11// C99 basically consist of a bunch of binary operators with unary operators and 12// other random stuff at the leaves. 13// 14// In the C99 grammar, these unary operators bind tightest and are represented 15// as the 'cast-expression' production. Everything else is either a binary 16// operator (e.g. '/') or a ternary operator ("?:"). The unary leaves are 17// handled by ParseCastExpression, the higher level pieces are handled by 18// ParseBinaryExpression. 19// 20//===----------------------------------------------------------------------===// 21 22#include "clang/Parse/Parser.h" 23#include "clang/Sema/DeclSpec.h" 24#include "clang/Sema/Scope.h" 25#include "clang/Sema/ParsedTemplate.h" 26#include "clang/Basic/PrettyStackTrace.h" 27#include "RAIIObjectsForParser.h" 28#include "llvm/ADT/SmallVector.h" 29#include "llvm/ADT/SmallString.h" 30using namespace clang; 31 32/// getBinOpPrecedence - Return the precedence of the specified binary operator 33/// token. 34static prec::Level getBinOpPrecedence(tok::TokenKind Kind, 35 bool GreaterThanIsOperator, 36 bool CPlusPlus0x) { 37 switch (Kind) { 38 case tok::greater: 39 // C++ [temp.names]p3: 40 // [...] When parsing a template-argument-list, the first 41 // non-nested > is taken as the ending delimiter rather than a 42 // greater-than operator. [...] 43 if (GreaterThanIsOperator) 44 return prec::Relational; 45 return prec::Unknown; 46 47 case tok::greatergreater: 48 // C++0x [temp.names]p3: 49 // 50 // [...] Similarly, the first non-nested >> is treated as two 51 // consecutive but distinct > tokens, the first of which is 52 // taken as the end of the template-argument-list and completes 53 // the template-id. [...] 54 if (GreaterThanIsOperator || !CPlusPlus0x) 55 return prec::Shift; 56 return prec::Unknown; 57 58 default: return prec::Unknown; 59 case tok::comma: return prec::Comma; 60 case tok::equal: 61 case tok::starequal: 62 case tok::slashequal: 63 case tok::percentequal: 64 case tok::plusequal: 65 case tok::minusequal: 66 case tok::lesslessequal: 67 case tok::greatergreaterequal: 68 case tok::ampequal: 69 case tok::caretequal: 70 case tok::pipeequal: return prec::Assignment; 71 case tok::question: return prec::Conditional; 72 case tok::pipepipe: return prec::LogicalOr; 73 case tok::ampamp: return prec::LogicalAnd; 74 case tok::pipe: return prec::InclusiveOr; 75 case tok::caret: return prec::ExclusiveOr; 76 case tok::amp: return prec::And; 77 case tok::exclaimequal: 78 case tok::equalequal: return prec::Equality; 79 case tok::lessequal: 80 case tok::less: 81 case tok::greaterequal: return prec::Relational; 82 case tok::lessless: return prec::Shift; 83 case tok::plus: 84 case tok::minus: return prec::Additive; 85 case tok::percent: 86 case tok::slash: 87 case tok::star: return prec::Multiplicative; 88 case tok::periodstar: 89 case tok::arrowstar: return prec::PointerToMember; 90 } 91} 92 93 94/// ParseExpression - Simple precedence-based parser for binary/ternary 95/// operators. 96/// 97/// Note: we diverge from the C99 grammar when parsing the assignment-expression 98/// production. C99 specifies that the LHS of an assignment operator should be 99/// parsed as a unary-expression, but consistency dictates that it be a 100/// conditional-expession. In practice, the important thing here is that the 101/// LHS of an assignment has to be an l-value, which productions between 102/// unary-expression and conditional-expression don't produce. Because we want 103/// consistency, we parse the LHS as a conditional-expression, then check for 104/// l-value-ness in semantic analysis stages. 105/// 106/// pm-expression: [C++ 5.5] 107/// cast-expression 108/// pm-expression '.*' cast-expression 109/// pm-expression '->*' cast-expression 110/// 111/// multiplicative-expression: [C99 6.5.5] 112/// Note: in C++, apply pm-expression instead of cast-expression 113/// cast-expression 114/// multiplicative-expression '*' cast-expression 115/// multiplicative-expression '/' cast-expression 116/// multiplicative-expression '%' cast-expression 117/// 118/// additive-expression: [C99 6.5.6] 119/// multiplicative-expression 120/// additive-expression '+' multiplicative-expression 121/// additive-expression '-' multiplicative-expression 122/// 123/// shift-expression: [C99 6.5.7] 124/// additive-expression 125/// shift-expression '<<' additive-expression 126/// shift-expression '>>' additive-expression 127/// 128/// relational-expression: [C99 6.5.8] 129/// shift-expression 130/// relational-expression '<' shift-expression 131/// relational-expression '>' shift-expression 132/// relational-expression '<=' shift-expression 133/// relational-expression '>=' shift-expression 134/// 135/// equality-expression: [C99 6.5.9] 136/// relational-expression 137/// equality-expression '==' relational-expression 138/// equality-expression '!=' relational-expression 139/// 140/// AND-expression: [C99 6.5.10] 141/// equality-expression 142/// AND-expression '&' equality-expression 143/// 144/// exclusive-OR-expression: [C99 6.5.11] 145/// AND-expression 146/// exclusive-OR-expression '^' AND-expression 147/// 148/// inclusive-OR-expression: [C99 6.5.12] 149/// exclusive-OR-expression 150/// inclusive-OR-expression '|' exclusive-OR-expression 151/// 152/// logical-AND-expression: [C99 6.5.13] 153/// inclusive-OR-expression 154/// logical-AND-expression '&&' inclusive-OR-expression 155/// 156/// logical-OR-expression: [C99 6.5.14] 157/// logical-AND-expression 158/// logical-OR-expression '||' logical-AND-expression 159/// 160/// conditional-expression: [C99 6.5.15] 161/// logical-OR-expression 162/// logical-OR-expression '?' expression ':' conditional-expression 163/// [GNU] logical-OR-expression '?' ':' conditional-expression 164/// [C++] the third operand is an assignment-expression 165/// 166/// assignment-expression: [C99 6.5.16] 167/// conditional-expression 168/// unary-expression assignment-operator assignment-expression 169/// [C++] throw-expression [C++ 15] 170/// 171/// assignment-operator: one of 172/// = *= /= %= += -= <<= >>= &= ^= |= 173/// 174/// expression: [C99 6.5.17] 175/// assignment-expression ...[opt] 176/// expression ',' assignment-expression ...[opt] 177ExprResult Parser::ParseExpression() { 178 ExprResult LHS(ParseAssignmentExpression()); 179 return ParseRHSOfBinaryExpression(move(LHS), prec::Comma); 180} 181 182/// This routine is called when the '@' is seen and consumed. 183/// Current token is an Identifier and is not a 'try'. This 184/// routine is necessary to disambiguate @try-statement from, 185/// for example, @encode-expression. 186/// 187ExprResult 188Parser::ParseExpressionWithLeadingAt(SourceLocation AtLoc) { 189 ExprResult LHS(ParseObjCAtExpression(AtLoc)); 190 return ParseRHSOfBinaryExpression(move(LHS), prec::Comma); 191} 192 193/// This routine is called when a leading '__extension__' is seen and 194/// consumed. This is necessary because the token gets consumed in the 195/// process of disambiguating between an expression and a declaration. 196ExprResult 197Parser::ParseExpressionWithLeadingExtension(SourceLocation ExtLoc) { 198 ExprResult LHS(true); 199 { 200 // Silence extension warnings in the sub-expression 201 ExtensionRAIIObject O(Diags); 202 203 LHS = ParseCastExpression(false); 204 } 205 206 if (!LHS.isInvalid()) 207 LHS = Actions.ActOnUnaryOp(getCurScope(), ExtLoc, tok::kw___extension__, 208 LHS.take()); 209 210 return ParseRHSOfBinaryExpression(move(LHS), prec::Comma); 211} 212 213/// ParseAssignmentExpression - Parse an expr that doesn't include commas. 214ExprResult Parser::ParseAssignmentExpression() { 215 if (Tok.is(tok::code_completion)) { 216 Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Expression); 217 cutOffParsing(); 218 return ExprError(); 219 } 220 221 if (Tok.is(tok::kw_throw)) 222 return ParseThrowExpression(); 223 224 ExprResult LHS = ParseCastExpression(/*isUnaryExpression=*/false); 225 return ParseRHSOfBinaryExpression(move(LHS), prec::Assignment); 226} 227 228/// ParseAssignmentExprWithObjCMessageExprStart - Parse an assignment expression 229/// where part of an objc message send has already been parsed. In this case 230/// LBracLoc indicates the location of the '[' of the message send, and either 231/// ReceiverName or ReceiverExpr is non-null indicating the receiver of the 232/// message. 233/// 234/// Since this handles full assignment-expression's, it handles postfix 235/// expressions and other binary operators for these expressions as well. 236ExprResult 237Parser::ParseAssignmentExprWithObjCMessageExprStart(SourceLocation LBracLoc, 238 SourceLocation SuperLoc, 239 ParsedType ReceiverType, 240 Expr *ReceiverExpr) { 241 ExprResult R 242 = ParseObjCMessageExpressionBody(LBracLoc, SuperLoc, 243 ReceiverType, ReceiverExpr); 244 R = ParsePostfixExpressionSuffix(R); 245 return ParseRHSOfBinaryExpression(R, prec::Assignment); 246} 247 248 249ExprResult Parser::ParseConstantExpression() { 250 // C++ [basic.def.odr]p2: 251 // An expression is potentially evaluated unless it appears where an 252 // integral constant expression is required (see 5.19) [...]. 253 EnterExpressionEvaluationContext Unevaluated(Actions, 254 Sema::Unevaluated); 255 256 ExprResult LHS(ParseCastExpression(false)); 257 return ParseRHSOfBinaryExpression(LHS, prec::Conditional); 258} 259 260/// ParseRHSOfBinaryExpression - Parse a binary expression that starts with 261/// LHS and has a precedence of at least MinPrec. 262ExprResult 263Parser::ParseRHSOfBinaryExpression(ExprResult LHS, prec::Level MinPrec) { 264 prec::Level NextTokPrec = getBinOpPrecedence(Tok.getKind(), 265 GreaterThanIsOperator, 266 getLang().CPlusPlus0x); 267 SourceLocation ColonLoc; 268 269 while (1) { 270 // If this token has a lower precedence than we are allowed to parse (e.g. 271 // because we are called recursively, or because the token is not a binop), 272 // then we are done! 273 if (NextTokPrec < MinPrec) 274 return move(LHS); 275 276 // Consume the operator, saving the operator token for error reporting. 277 Token OpToken = Tok; 278 ConsumeToken(); 279 280 // Special case handling for the ternary operator. 281 ExprResult TernaryMiddle(true); 282 if (NextTokPrec == prec::Conditional) { 283 if (Tok.isNot(tok::colon)) { 284 // Don't parse FOO:BAR as if it were a typo for FOO::BAR. 285 ColonProtectionRAIIObject X(*this); 286 287 // Handle this production specially: 288 // logical-OR-expression '?' expression ':' conditional-expression 289 // In particular, the RHS of the '?' is 'expression', not 290 // 'logical-OR-expression' as we might expect. 291 TernaryMiddle = ParseExpression(); 292 if (TernaryMiddle.isInvalid()) { 293 LHS = ExprError(); 294 TernaryMiddle = 0; 295 } 296 } else { 297 // Special case handling of "X ? Y : Z" where Y is empty: 298 // logical-OR-expression '?' ':' conditional-expression [GNU] 299 TernaryMiddle = 0; 300 Diag(Tok, diag::ext_gnu_conditional_expr); 301 } 302 303 if (Tok.is(tok::colon)) { 304 // Eat the colon. 305 ColonLoc = ConsumeToken(); 306 } else { 307 // Otherwise, we're missing a ':'. Assume that this was a typo that 308 // the user forgot. If we're not in a macro expansion, we can suggest 309 // a fixit hint. If there were two spaces before the current token, 310 // suggest inserting the colon in between them, otherwise insert ": ". 311 SourceLocation FILoc = Tok.getLocation(); 312 const char *FIText = ": "; 313 const SourceManager &SM = PP.getSourceManager(); 314 if (FILoc.isFileID() || PP.isAtStartOfMacroExpansion(FILoc)) { 315 FILoc = SM.getExpansionLoc(FILoc); 316 bool IsInvalid = false; 317 const char *SourcePtr = 318 SM.getCharacterData(FILoc.getLocWithOffset(-1), &IsInvalid); 319 if (!IsInvalid && *SourcePtr == ' ') { 320 SourcePtr = 321 SM.getCharacterData(FILoc.getLocWithOffset(-2), &IsInvalid); 322 if (!IsInvalid && *SourcePtr == ' ') { 323 FILoc = FILoc.getLocWithOffset(-1); 324 FIText = ":"; 325 } 326 } 327 } 328 329 Diag(Tok, diag::err_expected_colon) 330 << FixItHint::CreateInsertion(FILoc, FIText); 331 Diag(OpToken, diag::note_matching) << "?"; 332 ColonLoc = Tok.getLocation(); 333 } 334 } 335 336 // Code completion for the right-hand side of an assignment expression 337 // goes through a special hook that takes the left-hand side into account. 338 if (Tok.is(tok::code_completion) && NextTokPrec == prec::Assignment) { 339 Actions.CodeCompleteAssignmentRHS(getCurScope(), LHS.get()); 340 cutOffParsing(); 341 return ExprError(); 342 } 343 344 // Parse another leaf here for the RHS of the operator. 345 // ParseCastExpression works here because all RHS expressions in C have it 346 // as a prefix, at least. However, in C++, an assignment-expression could 347 // be a throw-expression, which is not a valid cast-expression. 348 // Therefore we need some special-casing here. 349 // Also note that the third operand of the conditional operator is 350 // an assignment-expression in C++. 351 ExprResult RHS; 352 if (getLang().CPlusPlus && NextTokPrec <= prec::Conditional) 353 RHS = ParseAssignmentExpression(); 354 else 355 RHS = ParseCastExpression(false); 356 357 if (RHS.isInvalid()) 358 LHS = ExprError(); 359 360 // Remember the precedence of this operator and get the precedence of the 361 // operator immediately to the right of the RHS. 362 prec::Level ThisPrec = NextTokPrec; 363 NextTokPrec = getBinOpPrecedence(Tok.getKind(), GreaterThanIsOperator, 364 getLang().CPlusPlus0x); 365 366 // Assignment and conditional expressions are right-associative. 367 bool isRightAssoc = ThisPrec == prec::Conditional || 368 ThisPrec == prec::Assignment; 369 370 // Get the precedence of the operator to the right of the RHS. If it binds 371 // more tightly with RHS than we do, evaluate it completely first. 372 if (ThisPrec < NextTokPrec || 373 (ThisPrec == NextTokPrec && isRightAssoc)) { 374 // If this is left-associative, only parse things on the RHS that bind 375 // more tightly than the current operator. If it is left-associative, it 376 // is okay, to bind exactly as tightly. For example, compile A=B=C=D as 377 // A=(B=(C=D)), where each paren is a level of recursion here. 378 // The function takes ownership of the RHS. 379 RHS = ParseRHSOfBinaryExpression(RHS, 380 static_cast<prec::Level>(ThisPrec + !isRightAssoc)); 381 382 if (RHS.isInvalid()) 383 LHS = ExprError(); 384 385 NextTokPrec = getBinOpPrecedence(Tok.getKind(), GreaterThanIsOperator, 386 getLang().CPlusPlus0x); 387 } 388 assert(NextTokPrec <= ThisPrec && "Recursion didn't work!"); 389 390 if (!LHS.isInvalid()) { 391 // Combine the LHS and RHS into the LHS (e.g. build AST). 392 if (TernaryMiddle.isInvalid()) { 393 // If we're using '>>' as an operator within a template 394 // argument list (in C++98), suggest the addition of 395 // parentheses so that the code remains well-formed in C++0x. 396 if (!GreaterThanIsOperator && OpToken.is(tok::greatergreater)) 397 SuggestParentheses(OpToken.getLocation(), 398 diag::warn_cxx0x_right_shift_in_template_arg, 399 SourceRange(Actions.getExprRange(LHS.get()).getBegin(), 400 Actions.getExprRange(RHS.get()).getEnd())); 401 402 LHS = Actions.ActOnBinOp(getCurScope(), OpToken.getLocation(), 403 OpToken.getKind(), LHS.take(), RHS.take()); 404 } else 405 LHS = Actions.ActOnConditionalOp(OpToken.getLocation(), ColonLoc, 406 LHS.take(), TernaryMiddle.take(), 407 RHS.take()); 408 } 409 } 410} 411 412/// ParseCastExpression - Parse a cast-expression, or, if isUnaryExpression is 413/// true, parse a unary-expression. isAddressOfOperand exists because an 414/// id-expression that is the operand of address-of gets special treatment 415/// due to member pointers. 416/// 417ExprResult Parser::ParseCastExpression(bool isUnaryExpression, 418 bool isAddressOfOperand, 419 bool isTypeCast) { 420 bool NotCastExpr; 421 ExprResult Res = ParseCastExpression(isUnaryExpression, 422 isAddressOfOperand, 423 NotCastExpr, 424 isTypeCast); 425 if (NotCastExpr) 426 Diag(Tok, diag::err_expected_expression); 427 return move(Res); 428} 429 430/// ParseCastExpression - Parse a cast-expression, or, if isUnaryExpression is 431/// true, parse a unary-expression. isAddressOfOperand exists because an 432/// id-expression that is the operand of address-of gets special treatment 433/// due to member pointers. NotCastExpr is set to true if the token is not the 434/// start of a cast-expression, and no diagnostic is emitted in this case. 435/// 436/// cast-expression: [C99 6.5.4] 437/// unary-expression 438/// '(' type-name ')' cast-expression 439/// 440/// unary-expression: [C99 6.5.3] 441/// postfix-expression 442/// '++' unary-expression 443/// '--' unary-expression 444/// unary-operator cast-expression 445/// 'sizeof' unary-expression 446/// 'sizeof' '(' type-name ')' 447/// [C++0x] 'sizeof' '...' '(' identifier ')' 448/// [GNU] '__alignof' unary-expression 449/// [GNU] '__alignof' '(' type-name ')' 450/// [C++0x] 'alignof' '(' type-id ')' 451/// [GNU] '&&' identifier 452/// [C++] new-expression 453/// [C++] delete-expression 454/// [C++0x] 'noexcept' '(' expression ')' 455/// 456/// unary-operator: one of 457/// '&' '*' '+' '-' '~' '!' 458/// [GNU] '__extension__' '__real' '__imag' 459/// 460/// primary-expression: [C99 6.5.1] 461/// [C99] identifier 462/// [C++] id-expression 463/// constant 464/// string-literal 465/// [C++] boolean-literal [C++ 2.13.5] 466/// [C++0x] 'nullptr' [C++0x 2.14.7] 467/// '(' expression ')' 468/// [C1X] generic-selection 469/// '__func__' [C99 6.4.2.2] 470/// [GNU] '__FUNCTION__' 471/// [GNU] '__PRETTY_FUNCTION__' 472/// [GNU] '(' compound-statement ')' 473/// [GNU] '__builtin_va_arg' '(' assignment-expression ',' type-name ')' 474/// [GNU] '__builtin_offsetof' '(' type-name ',' offsetof-member-designator')' 475/// [GNU] '__builtin_choose_expr' '(' assign-expr ',' assign-expr ',' 476/// assign-expr ')' 477/// [GNU] '__builtin_types_compatible_p' '(' type-name ',' type-name ')' 478/// [GNU] '__null' 479/// [OBJC] '[' objc-message-expr ']' 480/// [OBJC] '@selector' '(' objc-selector-arg ')' 481/// [OBJC] '@protocol' '(' identifier ')' 482/// [OBJC] '@encode' '(' type-name ')' 483/// [OBJC] objc-string-literal 484/// [C++] simple-type-specifier '(' expression-list[opt] ')' [C++ 5.2.3] 485/// [C++0x] simple-type-specifier braced-init-list [C++ 5.2.3] 486/// [C++] typename-specifier '(' expression-list[opt] ')' [C++ 5.2.3] 487/// [C++0x] typename-specifier braced-init-list [C++ 5.2.3] 488/// [C++] 'const_cast' '<' type-name '>' '(' expression ')' [C++ 5.2p1] 489/// [C++] 'dynamic_cast' '<' type-name '>' '(' expression ')' [C++ 5.2p1] 490/// [C++] 'reinterpret_cast' '<' type-name '>' '(' expression ')' [C++ 5.2p1] 491/// [C++] 'static_cast' '<' type-name '>' '(' expression ')' [C++ 5.2p1] 492/// [C++] 'typeid' '(' expression ')' [C++ 5.2p1] 493/// [C++] 'typeid' '(' type-id ')' [C++ 5.2p1] 494/// [C++] 'this' [C++ 9.3.2] 495/// [G++] unary-type-trait '(' type-id ')' 496/// [G++] binary-type-trait '(' type-id ',' type-id ')' [TODO] 497/// [EMBT] array-type-trait '(' type-id ',' integer ')' 498/// [clang] '^' block-literal 499/// 500/// constant: [C99 6.4.4] 501/// integer-constant 502/// floating-constant 503/// enumeration-constant -> identifier 504/// character-constant 505/// 506/// id-expression: [C++ 5.1] 507/// unqualified-id 508/// qualified-id 509/// 510/// unqualified-id: [C++ 5.1] 511/// identifier 512/// operator-function-id 513/// conversion-function-id 514/// '~' class-name 515/// template-id 516/// 517/// new-expression: [C++ 5.3.4] 518/// '::'[opt] 'new' new-placement[opt] new-type-id 519/// new-initializer[opt] 520/// '::'[opt] 'new' new-placement[opt] '(' type-id ')' 521/// new-initializer[opt] 522/// 523/// delete-expression: [C++ 5.3.5] 524/// '::'[opt] 'delete' cast-expression 525/// '::'[opt] 'delete' '[' ']' cast-expression 526/// 527/// [GNU/Embarcadero] unary-type-trait: 528/// '__is_arithmetic' 529/// '__is_floating_point' 530/// '__is_integral' 531/// '__is_lvalue_expr' 532/// '__is_rvalue_expr' 533/// '__is_complete_type' 534/// '__is_void' 535/// '__is_array' 536/// '__is_function' 537/// '__is_reference' 538/// '__is_lvalue_reference' 539/// '__is_rvalue_reference' 540/// '__is_fundamental' 541/// '__is_object' 542/// '__is_scalar' 543/// '__is_compound' 544/// '__is_pointer' 545/// '__is_member_object_pointer' 546/// '__is_member_function_pointer' 547/// '__is_member_pointer' 548/// '__is_const' 549/// '__is_volatile' 550/// '__is_trivial' 551/// '__is_standard_layout' 552/// '__is_signed' 553/// '__is_unsigned' 554/// 555/// [GNU] unary-type-trait: 556/// '__has_nothrow_assign' 557/// '__has_nothrow_copy' 558/// '__has_nothrow_constructor' 559/// '__has_trivial_assign' [TODO] 560/// '__has_trivial_copy' [TODO] 561/// '__has_trivial_constructor' 562/// '__has_trivial_destructor' 563/// '__has_virtual_destructor' 564/// '__is_abstract' [TODO] 565/// '__is_class' 566/// '__is_empty' [TODO] 567/// '__is_enum' 568/// '__is_pod' 569/// '__is_polymorphic' 570/// '__is_trivial' 571/// '__is_union' 572/// 573/// [Clang] unary-type-trait: 574/// '__trivially_copyable' 575/// 576/// binary-type-trait: 577/// [GNU] '__is_base_of' 578/// [MS] '__is_convertible_to' 579/// '__is_convertible' 580/// '__is_same' 581/// 582/// [Embarcadero] array-type-trait: 583/// '__array_rank' 584/// '__array_extent' 585/// 586/// [Embarcadero] expression-trait: 587/// '__is_lvalue_expr' 588/// '__is_rvalue_expr' 589/// 590ExprResult Parser::ParseCastExpression(bool isUnaryExpression, 591 bool isAddressOfOperand, 592 bool &NotCastExpr, 593 bool isTypeCast) { 594 ExprResult Res; 595 tok::TokenKind SavedKind = Tok.getKind(); 596 NotCastExpr = false; 597 598 // This handles all of cast-expression, unary-expression, postfix-expression, 599 // and primary-expression. We handle them together like this for efficiency 600 // and to simplify handling of an expression starting with a '(' token: which 601 // may be one of a parenthesized expression, cast-expression, compound literal 602 // expression, or statement expression. 603 // 604 // If the parsed tokens consist of a primary-expression, the cases below 605 // break out of the switch; at the end we call ParsePostfixExpressionSuffix 606 // to handle the postfix expression suffixes. Cases that cannot be followed 607 // by postfix exprs should return without invoking 608 // ParsePostfixExpressionSuffix. 609 switch (SavedKind) { 610 case tok::l_paren: { 611 // If this expression is limited to being a unary-expression, the parent can 612 // not start a cast expression. 613 ParenParseOption ParenExprType = 614 (isUnaryExpression && !getLang().CPlusPlus)? CompoundLiteral : CastExpr; 615 ParsedType CastTy; 616 SourceLocation RParenLoc; 617 618 { 619 // The inside of the parens don't need to be a colon protected scope, and 620 // isn't immediately a message send. 621 ColonProtectionRAIIObject X(*this, false); 622 623 Res = ParseParenExpression(ParenExprType, false/*stopIfCastExr*/, 624 isTypeCast, CastTy, RParenLoc); 625 } 626 627 switch (ParenExprType) { 628 case SimpleExpr: break; // Nothing else to do. 629 case CompoundStmt: break; // Nothing else to do. 630 case CompoundLiteral: 631 // We parsed '(' type-name ')' '{' ... '}'. If any suffixes of 632 // postfix-expression exist, parse them now. 633 break; 634 case CastExpr: 635 // We have parsed the cast-expression and no postfix-expr pieces are 636 // following. 637 return move(Res); 638 } 639 640 break; 641 } 642 643 // primary-expression 644 case tok::numeric_constant: 645 // constant: integer-constant 646 // constant: floating-constant 647 648 Res = Actions.ActOnNumericConstant(Tok); 649 ConsumeToken(); 650 break; 651 652 case tok::kw_true: 653 case tok::kw_false: 654 return ParseCXXBoolLiteral(); 655 656 case tok::kw_nullptr: 657 Diag(Tok, diag::warn_cxx98_compat_nullptr); 658 return Actions.ActOnCXXNullPtrLiteral(ConsumeToken()); 659 660 case tok::annot_primary_expr: 661 assert(Res.get() == 0 && "Stray primary-expression annotation?"); 662 Res = getExprAnnotation(Tok); 663 ConsumeToken(); 664 break; 665 666 case tok::identifier: { // primary-expression: identifier 667 // unqualified-id: identifier 668 // constant: enumeration-constant 669 // Turn a potentially qualified name into a annot_typename or 670 // annot_cxxscope if it would be valid. This handles things like x::y, etc. 671 if (getLang().CPlusPlus) { 672 // Avoid the unnecessary parse-time lookup in the common case 673 // where the syntax forbids a type. 674 const Token &Next = NextToken(); 675 if (Next.is(tok::coloncolon) || 676 (!ColonIsSacred && Next.is(tok::colon)) || 677 Next.is(tok::less) || 678 Next.is(tok::l_paren)) { 679 // If TryAnnotateTypeOrScopeToken annotates the token, tail recurse. 680 if (TryAnnotateTypeOrScopeToken()) 681 return ExprError(); 682 if (!Tok.is(tok::identifier)) 683 return ParseCastExpression(isUnaryExpression, isAddressOfOperand); 684 } 685 } 686 687 // Consume the identifier so that we can see if it is followed by a '(' or 688 // '.'. 689 IdentifierInfo &II = *Tok.getIdentifierInfo(); 690 SourceLocation ILoc = ConsumeToken(); 691 692 // Support 'Class.property' and 'super.property' notation. 693 if (getLang().ObjC1 && Tok.is(tok::period) && 694 (Actions.getTypeName(II, ILoc, getCurScope()) || 695 // Allow the base to be 'super' if in an objc-method. 696 (&II == Ident_super && getCurScope()->isInObjcMethodScope()))) { 697 ConsumeToken(); 698 699 if (Tok.isNot(tok::identifier)) { 700 Diag(Tok, diag::err_expected_property_name); 701 return ExprError(); 702 } 703 IdentifierInfo &PropertyName = *Tok.getIdentifierInfo(); 704 SourceLocation PropertyLoc = ConsumeToken(); 705 706 Res = Actions.ActOnClassPropertyRefExpr(II, PropertyName, 707 ILoc, PropertyLoc); 708 break; 709 } 710 711 // In an Objective-C method, if we have "super" followed by an identifier, 712 // the token sequence is ill-formed. However, if there's a ':' or ']' after 713 // that identifier, this is probably a message send with a missing open 714 // bracket. Treat it as such. 715 if (getLang().ObjC1 && &II == Ident_super && !InMessageExpression && 716 getCurScope()->isInObjcMethodScope() && 717 ((Tok.is(tok::identifier) && 718 (NextToken().is(tok::colon) || NextToken().is(tok::r_square))) || 719 Tok.is(tok::code_completion))) { 720 Res = ParseObjCMessageExpressionBody(SourceLocation(), ILoc, ParsedType(), 721 0); 722 break; 723 } 724 725 // If we have an Objective-C class name followed by an identifier 726 // and either ':' or ']', this is an Objective-C class message 727 // send that's missing the opening '['. Recovery 728 // appropriately. Also take this path if we're performing code 729 // completion after an Objective-C class name. 730 if (getLang().ObjC1 && 731 ((Tok.is(tok::identifier) && !InMessageExpression) || 732 Tok.is(tok::code_completion))) { 733 const Token& Next = NextToken(); 734 if (Tok.is(tok::code_completion) || 735 Next.is(tok::colon) || Next.is(tok::r_square)) 736 if (ParsedType Typ = Actions.getTypeName(II, ILoc, getCurScope())) 737 if (Typ.get()->isObjCObjectOrInterfaceType()) { 738 // Fake up a Declarator to use with ActOnTypeName. 739 DeclSpec DS(AttrFactory); 740 DS.SetRangeStart(ILoc); 741 DS.SetRangeEnd(ILoc); 742 const char *PrevSpec = 0; 743 unsigned DiagID; 744 DS.SetTypeSpecType(TST_typename, ILoc, PrevSpec, DiagID, Typ); 745 746 Declarator DeclaratorInfo(DS, Declarator::TypeNameContext); 747 TypeResult Ty = Actions.ActOnTypeName(getCurScope(), 748 DeclaratorInfo); 749 if (Ty.isInvalid()) 750 break; 751 752 Res = ParseObjCMessageExpressionBody(SourceLocation(), 753 SourceLocation(), 754 Ty.get(), 0); 755 break; 756 } 757 } 758 759 // Make sure to pass down the right value for isAddressOfOperand. 760 if (isAddressOfOperand && isPostfixExpressionSuffixStart()) 761 isAddressOfOperand = false; 762 763 // Function designators are allowed to be undeclared (C99 6.5.1p2), so we 764 // need to know whether or not this identifier is a function designator or 765 // not. 766 UnqualifiedId Name; 767 CXXScopeSpec ScopeSpec; 768 Name.setIdentifier(&II, ILoc); 769 Res = Actions.ActOnIdExpression(getCurScope(), ScopeSpec, Name, 770 Tok.is(tok::l_paren), isAddressOfOperand); 771 break; 772 } 773 case tok::char_constant: // constant: character-constant 774 case tok::wide_char_constant: 775 case tok::utf16_char_constant: 776 case tok::utf32_char_constant: 777 Res = Actions.ActOnCharacterConstant(Tok); 778 ConsumeToken(); 779 break; 780 case tok::kw___func__: // primary-expression: __func__ [C99 6.4.2.2] 781 case tok::kw___FUNCTION__: // primary-expression: __FUNCTION__ [GNU] 782 case tok::kw___PRETTY_FUNCTION__: // primary-expression: __P..Y_F..N__ [GNU] 783 Res = Actions.ActOnPredefinedExpr(Tok.getLocation(), SavedKind); 784 ConsumeToken(); 785 break; 786 case tok::string_literal: // primary-expression: string-literal 787 case tok::wide_string_literal: 788 case tok::utf8_string_literal: 789 case tok::utf16_string_literal: 790 case tok::utf32_string_literal: 791 Res = ParseStringLiteralExpression(); 792 break; 793 case tok::kw__Generic: // primary-expression: generic-selection [C1X 6.5.1] 794 Res = ParseGenericSelectionExpression(); 795 break; 796 case tok::kw___builtin_va_arg: 797 case tok::kw___builtin_offsetof: 798 case tok::kw___builtin_choose_expr: 799 case tok::kw___builtin_astype: // primary-expression: [OCL] as_type() 800 return ParseBuiltinPrimaryExpression(); 801 case tok::kw___null: 802 return Actions.ActOnGNUNullExpr(ConsumeToken()); 803 804 case tok::plusplus: // unary-expression: '++' unary-expression [C99] 805 case tok::minusminus: { // unary-expression: '--' unary-expression [C99] 806 // C++ [expr.unary] has: 807 // unary-expression: 808 // ++ cast-expression 809 // -- cast-expression 810 SourceLocation SavedLoc = ConsumeToken(); 811 Res = ParseCastExpression(!getLang().CPlusPlus); 812 if (!Res.isInvalid()) 813 Res = Actions.ActOnUnaryOp(getCurScope(), SavedLoc, SavedKind, Res.get()); 814 return move(Res); 815 } 816 case tok::amp: { // unary-expression: '&' cast-expression 817 // Special treatment because of member pointers 818 SourceLocation SavedLoc = ConsumeToken(); 819 Res = ParseCastExpression(false, true); 820 if (!Res.isInvalid()) 821 Res = Actions.ActOnUnaryOp(getCurScope(), SavedLoc, SavedKind, Res.get()); 822 return move(Res); 823 } 824 825 case tok::star: // unary-expression: '*' cast-expression 826 case tok::plus: // unary-expression: '+' cast-expression 827 case tok::minus: // unary-expression: '-' cast-expression 828 case tok::tilde: // unary-expression: '~' cast-expression 829 case tok::exclaim: // unary-expression: '!' cast-expression 830 case tok::kw___real: // unary-expression: '__real' cast-expression [GNU] 831 case tok::kw___imag: { // unary-expression: '__imag' cast-expression [GNU] 832 SourceLocation SavedLoc = ConsumeToken(); 833 Res = ParseCastExpression(false); 834 if (!Res.isInvalid()) 835 Res = Actions.ActOnUnaryOp(getCurScope(), SavedLoc, SavedKind, Res.get()); 836 return move(Res); 837 } 838 839 case tok::kw___extension__:{//unary-expression:'__extension__' cast-expr [GNU] 840 // __extension__ silences extension warnings in the subexpression. 841 ExtensionRAIIObject O(Diags); // Use RAII to do this. 842 SourceLocation SavedLoc = ConsumeToken(); 843 Res = ParseCastExpression(false); 844 if (!Res.isInvalid()) 845 Res = Actions.ActOnUnaryOp(getCurScope(), SavedLoc, SavedKind, Res.get()); 846 return move(Res); 847 } 848 case tok::kw_sizeof: // unary-expression: 'sizeof' unary-expression 849 // unary-expression: 'sizeof' '(' type-name ')' 850 case tok::kw_alignof: 851 case tok::kw___alignof: // unary-expression: '__alignof' unary-expression 852 // unary-expression: '__alignof' '(' type-name ')' 853 // unary-expression: 'alignof' '(' type-id ')' 854 case tok::kw_vec_step: // unary-expression: OpenCL 'vec_step' expression 855 return ParseUnaryExprOrTypeTraitExpression(); 856 case tok::ampamp: { // unary-expression: '&&' identifier 857 SourceLocation AmpAmpLoc = ConsumeToken(); 858 if (Tok.isNot(tok::identifier)) 859 return ExprError(Diag(Tok, diag::err_expected_ident)); 860 861 if (getCurScope()->getFnParent() == 0) 862 return ExprError(Diag(Tok, diag::err_address_of_label_outside_fn)); 863 864 Diag(AmpAmpLoc, diag::ext_gnu_address_of_label); 865 LabelDecl *LD = Actions.LookupOrCreateLabel(Tok.getIdentifierInfo(), 866 Tok.getLocation()); 867 Res = Actions.ActOnAddrLabel(AmpAmpLoc, Tok.getLocation(), LD); 868 ConsumeToken(); 869 return move(Res); 870 } 871 case tok::kw_const_cast: 872 case tok::kw_dynamic_cast: 873 case tok::kw_reinterpret_cast: 874 case tok::kw_static_cast: 875 Res = ParseCXXCasts(); 876 break; 877 case tok::kw_typeid: 878 Res = ParseCXXTypeid(); 879 break; 880 case tok::kw___uuidof: 881 Res = ParseCXXUuidof(); 882 break; 883 case tok::kw_this: 884 Res = ParseCXXThis(); 885 break; 886 887 case tok::annot_typename: 888 if (isStartOfObjCClassMessageMissingOpenBracket()) { 889 ParsedType Type = getTypeAnnotation(Tok); 890 891 // Fake up a Declarator to use with ActOnTypeName. 892 DeclSpec DS(AttrFactory); 893 DS.SetRangeStart(Tok.getLocation()); 894 DS.SetRangeEnd(Tok.getLastLoc()); 895 896 const char *PrevSpec = 0; 897 unsigned DiagID; 898 DS.SetTypeSpecType(TST_typename, Tok.getAnnotationEndLoc(), 899 PrevSpec, DiagID, Type); 900 901 Declarator DeclaratorInfo(DS, Declarator::TypeNameContext); 902 TypeResult Ty = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo); 903 if (Ty.isInvalid()) 904 break; 905 906 ConsumeToken(); 907 Res = ParseObjCMessageExpressionBody(SourceLocation(), SourceLocation(), 908 Ty.get(), 0); 909 break; 910 } 911 // Fall through 912 913 case tok::kw_char: 914 case tok::kw_wchar_t: 915 case tok::kw_char16_t: 916 case tok::kw_char32_t: 917 case tok::kw_bool: 918 case tok::kw_short: 919 case tok::kw_int: 920 case tok::kw_long: 921 case tok::kw___int64: 922 case tok::kw_signed: 923 case tok::kw_unsigned: 924 case tok::kw_half: 925 case tok::kw_float: 926 case tok::kw_double: 927 case tok::kw_void: 928 case tok::kw_typename: 929 case tok::kw_typeof: 930 case tok::kw___vector: { 931 if (!getLang().CPlusPlus) { 932 Diag(Tok, diag::err_expected_expression); 933 return ExprError(); 934 } 935 936 if (SavedKind == tok::kw_typename) { 937 // postfix-expression: typename-specifier '(' expression-list[opt] ')' 938 // typename-specifier braced-init-list 939 if (TryAnnotateTypeOrScopeToken()) 940 return ExprError(); 941 } 942 943 // postfix-expression: simple-type-specifier '(' expression-list[opt] ')' 944 // simple-type-specifier braced-init-list 945 // 946 DeclSpec DS(AttrFactory); 947 ParseCXXSimpleTypeSpecifier(DS); 948 if (Tok.isNot(tok::l_paren) && 949 (!getLang().CPlusPlus0x || Tok.isNot(tok::l_brace))) 950 return ExprError(Diag(Tok, diag::err_expected_lparen_after_type) 951 << DS.getSourceRange()); 952 953 if (Tok.is(tok::l_brace)) 954 Diag(Tok, diag::warn_cxx98_compat_generalized_initializer_lists); 955 956 Res = ParseCXXTypeConstructExpression(DS); 957 break; 958 } 959 960 case tok::annot_cxxscope: { // [C++] id-expression: qualified-id 961 // If TryAnnotateTypeOrScopeToken annotates the token, tail recurse. 962 // (We can end up in this situation after tentative parsing.) 963 if (TryAnnotateTypeOrScopeToken()) 964 return ExprError(); 965 if (!Tok.is(tok::annot_cxxscope)) 966 return ParseCastExpression(isUnaryExpression, isAddressOfOperand, 967 NotCastExpr, isTypeCast); 968 969 Token Next = NextToken(); 970 if (Next.is(tok::annot_template_id)) { 971 TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Next); 972 if (TemplateId->Kind == TNK_Type_template) { 973 // We have a qualified template-id that we know refers to a 974 // type, translate it into a type and continue parsing as a 975 // cast expression. 976 CXXScopeSpec SS; 977 ParseOptionalCXXScopeSpecifier(SS, ParsedType(), 978 /*EnteringContext=*/false); 979 AnnotateTemplateIdTokenAsType(); 980 return ParseCastExpression(isUnaryExpression, isAddressOfOperand, 981 NotCastExpr, isTypeCast); 982 } 983 } 984 985 // Parse as an id-expression. 986 Res = ParseCXXIdExpression(isAddressOfOperand); 987 break; 988 } 989 990 case tok::annot_template_id: { // [C++] template-id 991 TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Tok); 992 if (TemplateId->Kind == TNK_Type_template) { 993 // We have a template-id that we know refers to a type, 994 // translate it into a type and continue parsing as a cast 995 // expression. 996 AnnotateTemplateIdTokenAsType(); 997 return ParseCastExpression(isUnaryExpression, isAddressOfOperand, 998 NotCastExpr, isTypeCast); 999 } 1000 1001 // Fall through to treat the template-id as an id-expression. 1002 } 1003 1004 case tok::kw_operator: // [C++] id-expression: operator/conversion-function-id 1005 Res = ParseCXXIdExpression(isAddressOfOperand); 1006 break; 1007 1008 case tok::coloncolon: { 1009 // ::foo::bar -> global qualified name etc. If TryAnnotateTypeOrScopeToken 1010 // annotates the token, tail recurse. 1011 if (TryAnnotateTypeOrScopeToken()) 1012 return ExprError(); 1013 if (!Tok.is(tok::coloncolon)) 1014 return ParseCastExpression(isUnaryExpression, isAddressOfOperand); 1015 1016 // ::new -> [C++] new-expression 1017 // ::delete -> [C++] delete-expression 1018 SourceLocation CCLoc = ConsumeToken(); 1019 if (Tok.is(tok::kw_new)) 1020 return ParseCXXNewExpression(true, CCLoc); 1021 if (Tok.is(tok::kw_delete)) 1022 return ParseCXXDeleteExpression(true, CCLoc); 1023 1024 // This is not a type name or scope specifier, it is an invalid expression. 1025 Diag(CCLoc, diag::err_expected_expression); 1026 return ExprError(); 1027 } 1028 1029 case tok::kw_new: // [C++] new-expression 1030 return ParseCXXNewExpression(false, Tok.getLocation()); 1031 1032 case tok::kw_delete: // [C++] delete-expression 1033 return ParseCXXDeleteExpression(false, Tok.getLocation()); 1034 1035 case tok::kw_noexcept: { // [C++0x] 'noexcept' '(' expression ')' 1036 Diag(Tok, diag::warn_cxx98_compat_noexcept_expr); 1037 SourceLocation KeyLoc = ConsumeToken(); 1038 BalancedDelimiterTracker T(*this, tok::l_paren); 1039 1040 if (T.expectAndConsume(diag::err_expected_lparen_after, "noexcept")) 1041 return ExprError(); 1042 // C++ [expr.unary.noexcept]p1: 1043 // The noexcept operator determines whether the evaluation of its operand, 1044 // which is an unevaluated operand, can throw an exception. 1045 EnterExpressionEvaluationContext Unevaluated(Actions, Sema::Unevaluated); 1046 ExprResult Result = ParseExpression(); 1047 1048 T.consumeClose(); 1049 1050 if (!Result.isInvalid()) 1051 Result = Actions.ActOnNoexceptExpr(KeyLoc, T.getOpenLocation(), 1052 Result.take(), T.getCloseLocation()); 1053 return move(Result); 1054 } 1055 1056 case tok::kw___is_abstract: // [GNU] unary-type-trait 1057 case tok::kw___is_class: 1058 case tok::kw___is_empty: 1059 case tok::kw___is_enum: 1060 case tok::kw___is_literal: 1061 case tok::kw___is_arithmetic: 1062 case tok::kw___is_integral: 1063 case tok::kw___is_floating_point: 1064 case tok::kw___is_complete_type: 1065 case tok::kw___is_void: 1066 case tok::kw___is_array: 1067 case tok::kw___is_function: 1068 case tok::kw___is_reference: 1069 case tok::kw___is_lvalue_reference: 1070 case tok::kw___is_rvalue_reference: 1071 case tok::kw___is_fundamental: 1072 case tok::kw___is_object: 1073 case tok::kw___is_scalar: 1074 case tok::kw___is_compound: 1075 case tok::kw___is_pointer: 1076 case tok::kw___is_member_object_pointer: 1077 case tok::kw___is_member_function_pointer: 1078 case tok::kw___is_member_pointer: 1079 case tok::kw___is_const: 1080 case tok::kw___is_volatile: 1081 case tok::kw___is_standard_layout: 1082 case tok::kw___is_signed: 1083 case tok::kw___is_unsigned: 1084 case tok::kw___is_literal_type: 1085 case tok::kw___is_pod: 1086 case tok::kw___is_polymorphic: 1087 case tok::kw___is_trivial: 1088 case tok::kw___is_trivially_copyable: 1089 case tok::kw___is_union: 1090 case tok::kw___has_trivial_constructor: 1091 case tok::kw___has_trivial_copy: 1092 case tok::kw___has_trivial_assign: 1093 case tok::kw___has_trivial_destructor: 1094 case tok::kw___has_nothrow_assign: 1095 case tok::kw___has_nothrow_copy: 1096 case tok::kw___has_nothrow_constructor: 1097 case tok::kw___has_virtual_destructor: 1098 return ParseUnaryTypeTrait(); 1099 1100 case tok::kw___builtin_types_compatible_p: 1101 case tok::kw___is_base_of: 1102 case tok::kw___is_same: 1103 case tok::kw___is_convertible: 1104 case tok::kw___is_convertible_to: 1105 return ParseBinaryTypeTrait(); 1106 1107 case tok::kw___array_rank: 1108 case tok::kw___array_extent: 1109 return ParseArrayTypeTrait(); 1110 1111 case tok::kw___is_lvalue_expr: 1112 case tok::kw___is_rvalue_expr: 1113 return ParseExpressionTrait(); 1114 1115 case tok::at: { 1116 SourceLocation AtLoc = ConsumeToken(); 1117 return ParseObjCAtExpression(AtLoc); 1118 } 1119 case tok::caret: 1120 Res = ParseBlockLiteralExpression(); 1121 break; 1122 case tok::code_completion: { 1123 Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Expression); 1124 cutOffParsing(); 1125 return ExprError(); 1126 } 1127 case tok::l_square: 1128 if (getLang().CPlusPlus0x) { 1129 if (getLang().ObjC1) { 1130 Res = TryParseLambdaExpression(); 1131 if (Res.isInvalid()) 1132 Res = ParseObjCMessageExpression(); 1133 break; 1134 } 1135 Res = ParseLambdaExpression(); 1136 break; 1137 } 1138 if (getLang().ObjC1) { 1139 Res = ParseObjCMessageExpression(); 1140 break; 1141 } 1142 // FALL THROUGH. 1143 default: 1144 NotCastExpr = true; 1145 return ExprError(); 1146 } 1147 1148 // These can be followed by postfix-expr pieces. 1149 return ParsePostfixExpressionSuffix(Res); 1150} 1151 1152/// ParsePostfixExpressionSuffix - Once the leading part of a postfix-expression 1153/// is parsed, this method parses any suffixes that apply. 1154/// 1155/// postfix-expression: [C99 6.5.2] 1156/// primary-expression 1157/// postfix-expression '[' expression ']' 1158/// postfix-expression '[' braced-init-list ']' 1159/// postfix-expression '(' argument-expression-list[opt] ')' 1160/// postfix-expression '.' identifier 1161/// postfix-expression '->' identifier 1162/// postfix-expression '++' 1163/// postfix-expression '--' 1164/// '(' type-name ')' '{' initializer-list '}' 1165/// '(' type-name ')' '{' initializer-list ',' '}' 1166/// 1167/// argument-expression-list: [C99 6.5.2] 1168/// argument-expression ...[opt] 1169/// argument-expression-list ',' assignment-expression ...[opt] 1170/// 1171ExprResult 1172Parser::ParsePostfixExpressionSuffix(ExprResult LHS) { 1173 // Now that the primary-expression piece of the postfix-expression has been 1174 // parsed, see if there are any postfix-expression pieces here. 1175 SourceLocation Loc; 1176 while (1) { 1177 switch (Tok.getKind()) { 1178 case tok::code_completion: 1179 if (InMessageExpression) 1180 return move(LHS); 1181 1182 Actions.CodeCompletePostfixExpression(getCurScope(), LHS); 1183 cutOffParsing(); 1184 return ExprError(); 1185 1186 case tok::identifier: 1187 // If we see identifier: after an expression, and we're not already in a 1188 // message send, then this is probably a message send with a missing 1189 // opening bracket '['. 1190 if (getLang().ObjC1 && !InMessageExpression && 1191 (NextToken().is(tok::colon) || NextToken().is(tok::r_square))) { 1192 LHS = ParseObjCMessageExpressionBody(SourceLocation(), SourceLocation(), 1193 ParsedType(), LHS.get()); 1194 break; 1195 } 1196 1197 // Fall through; this isn't a message send. 1198 1199 default: // Not a postfix-expression suffix. 1200 return move(LHS); 1201 case tok::l_square: { // postfix-expression: p-e '[' expression ']' 1202 // If we have a array postfix expression that starts on a new line and 1203 // Objective-C is enabled, it is highly likely that the user forgot a 1204 // semicolon after the base expression and that the array postfix-expr is 1205 // actually another message send. In this case, do some look-ahead to see 1206 // if the contents of the square brackets are obviously not a valid 1207 // expression and recover by pretending there is no suffix. 1208 if (getLang().ObjC1 && Tok.isAtStartOfLine() && 1209 isSimpleObjCMessageExpression()) 1210 return move(LHS); 1211 1212 BalancedDelimiterTracker T(*this, tok::l_square); 1213 T.consumeOpen(); 1214 Loc = T.getOpenLocation(); 1215 ExprResult Idx; 1216 if (getLang().CPlusPlus0x && Tok.is(tok::l_brace)) { 1217 Diag(Tok, diag::warn_cxx98_compat_generalized_initializer_lists); 1218 Idx = ParseBraceInitializer(); 1219 } else 1220 Idx = ParseExpression(); 1221 1222 SourceLocation RLoc = Tok.getLocation(); 1223 1224 if (!LHS.isInvalid() && !Idx.isInvalid() && Tok.is(tok::r_square)) { 1225 LHS = Actions.ActOnArraySubscriptExpr(getCurScope(), LHS.take(), Loc, 1226 Idx.take(), RLoc); 1227 } else 1228 LHS = ExprError(); 1229 1230 // Match the ']'. 1231 T.consumeClose(); 1232 break; 1233 } 1234 1235 case tok::l_paren: // p-e: p-e '(' argument-expression-list[opt] ')' 1236 case tok::lesslessless: { // p-e: p-e '<<<' argument-expression-list '>>>' 1237 // '(' argument-expression-list[opt] ')' 1238 tok::TokenKind OpKind = Tok.getKind(); 1239 InMessageExpressionRAIIObject InMessage(*this, false); 1240 1241 Expr *ExecConfig = 0; 1242 1243 BalancedDelimiterTracker LLLT(*this, tok::lesslessless); 1244 BalancedDelimiterTracker PT(*this, tok::l_paren); 1245 1246 if (OpKind == tok::lesslessless) { 1247 ExprVector ExecConfigExprs(Actions); 1248 CommaLocsTy ExecConfigCommaLocs; 1249 LLLT.consumeOpen(); 1250 1251 if (ParseExpressionList(ExecConfigExprs, ExecConfigCommaLocs)) { 1252 LHS = ExprError(); 1253 } 1254 1255 if (LHS.isInvalid()) { 1256 SkipUntil(tok::greatergreatergreater); 1257 } else if (LLLT.consumeClose()) { 1258 // There was an error closing the brackets 1259 LHS = ExprError(); 1260 } 1261 1262 if (!LHS.isInvalid()) { 1263 if (ExpectAndConsume(tok::l_paren, diag::err_expected_lparen, "")) 1264 LHS = ExprError(); 1265 else 1266 Loc = PrevTokLocation; 1267 } 1268 1269 if (!LHS.isInvalid()) { 1270 ExprResult ECResult = Actions.ActOnCUDAExecConfigExpr(getCurScope(), 1271 LLLT.getOpenLocation(), 1272 move_arg(ExecConfigExprs), 1273 LLLT.getCloseLocation()); 1274 if (ECResult.isInvalid()) 1275 LHS = ExprError(); 1276 else 1277 ExecConfig = ECResult.get(); 1278 } 1279 } else { 1280 PT.consumeOpen(); 1281 Loc = PT.getOpenLocation(); 1282 } 1283 1284 ExprVector ArgExprs(Actions); 1285 CommaLocsTy CommaLocs; 1286 1287 if (Tok.is(tok::code_completion)) { 1288 Actions.CodeCompleteCall(getCurScope(), LHS.get(), 0, 0); 1289 cutOffParsing(); 1290 return ExprError(); 1291 } 1292 1293 if (OpKind == tok::l_paren || !LHS.isInvalid()) { 1294 if (Tok.isNot(tok::r_paren)) { 1295 if (ParseExpressionList(ArgExprs, CommaLocs, &Sema::CodeCompleteCall, 1296 LHS.get())) { 1297 LHS = ExprError(); 1298 } 1299 } 1300 } 1301 1302 // Match the ')'. 1303 if (LHS.isInvalid()) { 1304 SkipUntil(tok::r_paren); 1305 } else if (Tok.isNot(tok::r_paren)) { 1306 PT.consumeClose(); 1307 LHS = ExprError(); 1308 } else { 1309 assert((ArgExprs.size() == 0 || 1310 ArgExprs.size()-1 == CommaLocs.size())&& 1311 "Unexpected number of commas!"); 1312 LHS = Actions.ActOnCallExpr(getCurScope(), LHS.take(), Loc, 1313 move_arg(ArgExprs), Tok.getLocation(), 1314 ExecConfig); 1315 PT.consumeClose(); 1316 } 1317 1318 break; 1319 } 1320 case tok::arrow: 1321 case tok::period: { 1322 // postfix-expression: p-e '->' template[opt] id-expression 1323 // postfix-expression: p-e '.' template[opt] id-expression 1324 tok::TokenKind OpKind = Tok.getKind(); 1325 SourceLocation OpLoc = ConsumeToken(); // Eat the "." or "->" token. 1326 1327 CXXScopeSpec SS; 1328 ParsedType ObjectType; 1329 bool MayBePseudoDestructor = false; 1330 if (getLang().CPlusPlus && !LHS.isInvalid()) { 1331 LHS = Actions.ActOnStartCXXMemberReference(getCurScope(), LHS.take(), 1332 OpLoc, OpKind, ObjectType, 1333 MayBePseudoDestructor); 1334 if (LHS.isInvalid()) 1335 break; 1336 1337 ParseOptionalCXXScopeSpecifier(SS, ObjectType, 1338 /*EnteringContext=*/false, 1339 &MayBePseudoDestructor); 1340 if (SS.isNotEmpty()) 1341 ObjectType = ParsedType(); 1342 } 1343 1344 if (Tok.is(tok::code_completion)) { 1345 // Code completion for a member access expression. 1346 Actions.CodeCompleteMemberReferenceExpr(getCurScope(), LHS.get(), 1347 OpLoc, OpKind == tok::arrow); 1348 1349 cutOffParsing(); 1350 return ExprError(); 1351 } 1352 1353 if (MayBePseudoDestructor && !LHS.isInvalid()) { 1354 LHS = ParseCXXPseudoDestructor(LHS.take(), OpLoc, OpKind, SS, 1355 ObjectType); 1356 break; 1357 } 1358 1359 // Either the action has told is that this cannot be a 1360 // pseudo-destructor expression (based on the type of base 1361 // expression), or we didn't see a '~' in the right place. We 1362 // can still parse a destructor name here, but in that case it 1363 // names a real destructor. 1364 // Allow explicit constructor calls in Microsoft mode. 1365 // FIXME: Add support for explicit call of template constructor. 1366 UnqualifiedId Name; 1367 if (ParseUnqualifiedId(SS, 1368 /*EnteringContext=*/false, 1369 /*AllowDestructorName=*/true, 1370 /*AllowConstructorName=*/ getLang().MicrosoftExt, 1371 ObjectType, 1372 Name)) 1373 LHS = ExprError(); 1374 1375 if (!LHS.isInvalid()) 1376 LHS = Actions.ActOnMemberAccessExpr(getCurScope(), LHS.take(), OpLoc, 1377 OpKind, SS, Name, ObjCImpDecl, 1378 Tok.is(tok::l_paren)); 1379 break; 1380 } 1381 case tok::plusplus: // postfix-expression: postfix-expression '++' 1382 case tok::minusminus: // postfix-expression: postfix-expression '--' 1383 if (!LHS.isInvalid()) { 1384 LHS = Actions.ActOnPostfixUnaryOp(getCurScope(), Tok.getLocation(), 1385 Tok.getKind(), LHS.take()); 1386 } 1387 ConsumeToken(); 1388 break; 1389 } 1390 } 1391} 1392 1393/// ParseExprAfterUnaryExprOrTypeTrait - We parsed a typeof/sizeof/alignof/ 1394/// vec_step and we are at the start of an expression or a parenthesized 1395/// type-id. OpTok is the operand token (typeof/sizeof/alignof). Returns the 1396/// expression (isCastExpr == false) or the type (isCastExpr == true). 1397/// 1398/// unary-expression: [C99 6.5.3] 1399/// 'sizeof' unary-expression 1400/// 'sizeof' '(' type-name ')' 1401/// [GNU] '__alignof' unary-expression 1402/// [GNU] '__alignof' '(' type-name ')' 1403/// [C++0x] 'alignof' '(' type-id ')' 1404/// 1405/// [GNU] typeof-specifier: 1406/// typeof ( expressions ) 1407/// typeof ( type-name ) 1408/// [GNU/C++] typeof unary-expression 1409/// 1410/// [OpenCL 1.1 6.11.12] vec_step built-in function: 1411/// vec_step ( expressions ) 1412/// vec_step ( type-name ) 1413/// 1414ExprResult 1415Parser::ParseExprAfterUnaryExprOrTypeTrait(const Token &OpTok, 1416 bool &isCastExpr, 1417 ParsedType &CastTy, 1418 SourceRange &CastRange) { 1419 1420 assert((OpTok.is(tok::kw_typeof) || OpTok.is(tok::kw_sizeof) || 1421 OpTok.is(tok::kw___alignof) || OpTok.is(tok::kw_alignof) || 1422 OpTok.is(tok::kw_vec_step)) && 1423 "Not a typeof/sizeof/alignof/vec_step expression!"); 1424 1425 ExprResult Operand; 1426 1427 // If the operand doesn't start with an '(', it must be an expression. 1428 if (Tok.isNot(tok::l_paren)) { 1429 isCastExpr = false; 1430 if (OpTok.is(tok::kw_typeof) && !getLang().CPlusPlus) { 1431 Diag(Tok,diag::err_expected_lparen_after_id) << OpTok.getIdentifierInfo(); 1432 return ExprError(); 1433 } 1434 1435 // C++0x [expr.sizeof]p1: 1436 // [...] The operand is either an expression, which is an unevaluated 1437 // operand (Clause 5) [...] 1438 // 1439 // The GNU typeof and alignof extensions also behave as unevaluated 1440 // operands. 1441 EnterExpressionEvaluationContext Unevaluated(Actions, 1442 Sema::Unevaluated); 1443 Operand = ParseCastExpression(true/*isUnaryExpression*/); 1444 } else { 1445 // If it starts with a '(', we know that it is either a parenthesized 1446 // type-name, or it is a unary-expression that starts with a compound 1447 // literal, or starts with a primary-expression that is a parenthesized 1448 // expression. 1449 ParenParseOption ExprType = CastExpr; 1450 SourceLocation LParenLoc = Tok.getLocation(), RParenLoc; 1451 1452 // C++0x [expr.sizeof]p1: 1453 // [...] The operand is either an expression, which is an unevaluated 1454 // operand (Clause 5) [...] 1455 // 1456 // The GNU typeof and alignof extensions also behave as unevaluated 1457 // operands. 1458 EnterExpressionEvaluationContext Unevaluated(Actions, 1459 Sema::Unevaluated); 1460 Operand = ParseParenExpression(ExprType, true/*stopIfCastExpr*/, 1461 false, CastTy, RParenLoc); 1462 CastRange = SourceRange(LParenLoc, RParenLoc); 1463 1464 // If ParseParenExpression parsed a '(typename)' sequence only, then this is 1465 // a type. 1466 if (ExprType == CastExpr) { 1467 isCastExpr = true; 1468 return ExprEmpty(); 1469 } 1470 1471 if (getLang().CPlusPlus || OpTok.isNot(tok::kw_typeof)) { 1472 // GNU typeof in C requires the expression to be parenthesized. Not so for 1473 // sizeof/alignof or in C++. Therefore, the parenthesized expression is 1474 // the start of a unary-expression, but doesn't include any postfix 1475 // pieces. Parse these now if present. 1476 if (!Operand.isInvalid()) 1477 Operand = ParsePostfixExpressionSuffix(Operand.get()); 1478 } 1479 } 1480 1481 // If we get here, the operand to the typeof/sizeof/alignof was an expresion. 1482 isCastExpr = false; 1483 return move(Operand); 1484} 1485 1486 1487/// ParseUnaryExprOrTypeTraitExpression - Parse a sizeof or alignof expression. 1488/// unary-expression: [C99 6.5.3] 1489/// 'sizeof' unary-expression 1490/// 'sizeof' '(' type-name ')' 1491/// [C++0x] 'sizeof' '...' '(' identifier ')' 1492/// [GNU] '__alignof' unary-expression 1493/// [GNU] '__alignof' '(' type-name ')' 1494/// [C++0x] 'alignof' '(' type-id ')' 1495ExprResult Parser::ParseUnaryExprOrTypeTraitExpression() { 1496 assert((Tok.is(tok::kw_sizeof) || Tok.is(tok::kw___alignof) 1497 || Tok.is(tok::kw_alignof) || Tok.is(tok::kw_vec_step)) && 1498 "Not a sizeof/alignof/vec_step expression!"); 1499 Token OpTok = Tok; 1500 ConsumeToken(); 1501 1502 // [C++0x] 'sizeof' '...' '(' identifier ')' 1503 if (Tok.is(tok::ellipsis) && OpTok.is(tok::kw_sizeof)) { 1504 SourceLocation EllipsisLoc = ConsumeToken(); 1505 SourceLocation LParenLoc, RParenLoc; 1506 IdentifierInfo *Name = 0; 1507 SourceLocation NameLoc; 1508 if (Tok.is(tok::l_paren)) { 1509 BalancedDelimiterTracker T(*this, tok::l_paren); 1510 T.consumeOpen(); 1511 LParenLoc = T.getOpenLocation(); 1512 if (Tok.is(tok::identifier)) { 1513 Name = Tok.getIdentifierInfo(); 1514 NameLoc = ConsumeToken(); 1515 T.consumeClose(); 1516 RParenLoc = T.getCloseLocation(); 1517 if (RParenLoc.isInvalid()) 1518 RParenLoc = PP.getLocForEndOfToken(NameLoc); 1519 } else { 1520 Diag(Tok, diag::err_expected_parameter_pack); 1521 SkipUntil(tok::r_paren); 1522 } 1523 } else if (Tok.is(tok::identifier)) { 1524 Name = Tok.getIdentifierInfo(); 1525 NameLoc = ConsumeToken(); 1526 LParenLoc = PP.getLocForEndOfToken(EllipsisLoc); 1527 RParenLoc = PP.getLocForEndOfToken(NameLoc); 1528 Diag(LParenLoc, diag::err_paren_sizeof_parameter_pack) 1529 << Name 1530 << FixItHint::CreateInsertion(LParenLoc, "(") 1531 << FixItHint::CreateInsertion(RParenLoc, ")"); 1532 } else { 1533 Diag(Tok, diag::err_sizeof_parameter_pack); 1534 } 1535 1536 if (!Name) 1537 return ExprError(); 1538 1539 return Actions.ActOnSizeofParameterPackExpr(getCurScope(), 1540 OpTok.getLocation(), 1541 *Name, NameLoc, 1542 RParenLoc); 1543 } 1544 1545 if (OpTok.is(tok::kw_alignof)) 1546 Diag(OpTok, diag::warn_cxx98_compat_alignof); 1547 1548 bool isCastExpr; 1549 ParsedType CastTy; 1550 SourceRange CastRange; 1551 ExprResult Operand = ParseExprAfterUnaryExprOrTypeTrait(OpTok, 1552 isCastExpr, 1553 CastTy, 1554 CastRange); 1555 1556 UnaryExprOrTypeTrait ExprKind = UETT_SizeOf; 1557 if (OpTok.is(tok::kw_alignof) || OpTok.is(tok::kw___alignof)) 1558 ExprKind = UETT_AlignOf; 1559 else if (OpTok.is(tok::kw_vec_step)) 1560 ExprKind = UETT_VecStep; 1561 1562 if (isCastExpr) 1563 return Actions.ActOnUnaryExprOrTypeTraitExpr(OpTok.getLocation(), 1564 ExprKind, 1565 /*isType=*/true, 1566 CastTy.getAsOpaquePtr(), 1567 CastRange); 1568 1569 // If we get here, the operand to the sizeof/alignof was an expresion. 1570 if (!Operand.isInvalid()) 1571 Operand = Actions.ActOnUnaryExprOrTypeTraitExpr(OpTok.getLocation(), 1572 ExprKind, 1573 /*isType=*/false, 1574 Operand.release(), 1575 CastRange); 1576 return move(Operand); 1577} 1578 1579/// ParseBuiltinPrimaryExpression 1580/// 1581/// primary-expression: [C99 6.5.1] 1582/// [GNU] '__builtin_va_arg' '(' assignment-expression ',' type-name ')' 1583/// [GNU] '__builtin_offsetof' '(' type-name ',' offsetof-member-designator')' 1584/// [GNU] '__builtin_choose_expr' '(' assign-expr ',' assign-expr ',' 1585/// assign-expr ')' 1586/// [GNU] '__builtin_types_compatible_p' '(' type-name ',' type-name ')' 1587/// [OCL] '__builtin_astype' '(' assignment-expression ',' type-name ')' 1588/// 1589/// [GNU] offsetof-member-designator: 1590/// [GNU] identifier 1591/// [GNU] offsetof-member-designator '.' identifier 1592/// [GNU] offsetof-member-designator '[' expression ']' 1593/// 1594ExprResult Parser::ParseBuiltinPrimaryExpression() { 1595 ExprResult Res; 1596 const IdentifierInfo *BuiltinII = Tok.getIdentifierInfo(); 1597 1598 tok::TokenKind T = Tok.getKind(); 1599 SourceLocation StartLoc = ConsumeToken(); // Eat the builtin identifier. 1600 1601 // All of these start with an open paren. 1602 if (Tok.isNot(tok::l_paren)) 1603 return ExprError(Diag(Tok, diag::err_expected_lparen_after_id) 1604 << BuiltinII); 1605 1606 BalancedDelimiterTracker PT(*this, tok::l_paren); 1607 PT.consumeOpen(); 1608 1609 // TODO: Build AST. 1610 1611 switch (T) { 1612 default: llvm_unreachable("Not a builtin primary expression!"); 1613 case tok::kw___builtin_va_arg: { 1614 ExprResult Expr(ParseAssignmentExpression()); 1615 1616 if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "",tok::r_paren)) 1617 Expr = ExprError(); 1618 1619 TypeResult Ty = ParseTypeName(); 1620 1621 if (Tok.isNot(tok::r_paren)) { 1622 Diag(Tok, diag::err_expected_rparen); 1623 Expr = ExprError(); 1624 } 1625 1626 if (Expr.isInvalid() || Ty.isInvalid()) 1627 Res = ExprError(); 1628 else 1629 Res = Actions.ActOnVAArg(StartLoc, Expr.take(), Ty.get(), ConsumeParen()); 1630 break; 1631 } 1632 case tok::kw___builtin_offsetof: { 1633 SourceLocation TypeLoc = Tok.getLocation(); 1634 TypeResult Ty = ParseTypeName(); 1635 if (Ty.isInvalid()) { 1636 SkipUntil(tok::r_paren); 1637 return ExprError(); 1638 } 1639 1640 if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "",tok::r_paren)) 1641 return ExprError(); 1642 1643 // We must have at least one identifier here. 1644 if (Tok.isNot(tok::identifier)) { 1645 Diag(Tok, diag::err_expected_ident); 1646 SkipUntil(tok::r_paren); 1647 return ExprError(); 1648 } 1649 1650 // Keep track of the various subcomponents we see. 1651 SmallVector<Sema::OffsetOfComponent, 4> Comps; 1652 1653 Comps.push_back(Sema::OffsetOfComponent()); 1654 Comps.back().isBrackets = false; 1655 Comps.back().U.IdentInfo = Tok.getIdentifierInfo(); 1656 Comps.back().LocStart = Comps.back().LocEnd = ConsumeToken(); 1657 1658 // FIXME: This loop leaks the index expressions on error. 1659 while (1) { 1660 if (Tok.is(tok::period)) { 1661 // offsetof-member-designator: offsetof-member-designator '.' identifier 1662 Comps.push_back(Sema::OffsetOfComponent()); 1663 Comps.back().isBrackets = false; 1664 Comps.back().LocStart = ConsumeToken(); 1665 1666 if (Tok.isNot(tok::identifier)) { 1667 Diag(Tok, diag::err_expected_ident); 1668 SkipUntil(tok::r_paren); 1669 return ExprError(); 1670 } 1671 Comps.back().U.IdentInfo = Tok.getIdentifierInfo(); 1672 Comps.back().LocEnd = ConsumeToken(); 1673 1674 } else if (Tok.is(tok::l_square)) { 1675 // offsetof-member-designator: offsetof-member-design '[' expression ']' 1676 Comps.push_back(Sema::OffsetOfComponent()); 1677 Comps.back().isBrackets = true; 1678 BalancedDelimiterTracker ST(*this, tok::l_square); 1679 ST.consumeOpen(); 1680 Comps.back().LocStart = ST.getOpenLocation(); 1681 Res = ParseExpression(); 1682 if (Res.isInvalid()) { 1683 SkipUntil(tok::r_paren); 1684 return move(Res); 1685 } 1686 Comps.back().U.E = Res.release(); 1687 1688 ST.consumeClose(); 1689 Comps.back().LocEnd = ST.getCloseLocation(); 1690 } else { 1691 if (Tok.isNot(tok::r_paren)) { 1692 PT.consumeClose(); 1693 Res = ExprError(); 1694 } else if (Ty.isInvalid()) { 1695 Res = ExprError(); 1696 } else { 1697 PT.consumeClose(); 1698 Res = Actions.ActOnBuiltinOffsetOf(getCurScope(), StartLoc, TypeLoc, 1699 Ty.get(), &Comps[0], Comps.size(), 1700 PT.getCloseLocation()); 1701 } 1702 break; 1703 } 1704 } 1705 break; 1706 } 1707 case tok::kw___builtin_choose_expr: { 1708 ExprResult Cond(ParseAssignmentExpression()); 1709 if (Cond.isInvalid()) { 1710 SkipUntil(tok::r_paren); 1711 return move(Cond); 1712 } 1713 if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "",tok::r_paren)) 1714 return ExprError(); 1715 1716 ExprResult Expr1(ParseAssignmentExpression()); 1717 if (Expr1.isInvalid()) { 1718 SkipUntil(tok::r_paren); 1719 return move(Expr1); 1720 } 1721 if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "",tok::r_paren)) 1722 return ExprError(); 1723 1724 ExprResult Expr2(ParseAssignmentExpression()); 1725 if (Expr2.isInvalid()) { 1726 SkipUntil(tok::r_paren); 1727 return move(Expr2); 1728 } 1729 if (Tok.isNot(tok::r_paren)) { 1730 Diag(Tok, diag::err_expected_rparen); 1731 return ExprError(); 1732 } 1733 Res = Actions.ActOnChooseExpr(StartLoc, Cond.take(), Expr1.take(), 1734 Expr2.take(), ConsumeParen()); 1735 break; 1736 } 1737 case tok::kw___builtin_astype: { 1738 // The first argument is an expression to be converted, followed by a comma. 1739 ExprResult Expr(ParseAssignmentExpression()); 1740 if (Expr.isInvalid()) { 1741 SkipUntil(tok::r_paren); 1742 return ExprError(); 1743 } 1744 1745 if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "", 1746 tok::r_paren)) 1747 return ExprError(); 1748 1749 // Second argument is the type to bitcast to. 1750 TypeResult DestTy = ParseTypeName(); 1751 if (DestTy.isInvalid()) 1752 return ExprError(); 1753 1754 // Attempt to consume the r-paren. 1755 if (Tok.isNot(tok::r_paren)) { 1756 Diag(Tok, diag::err_expected_rparen); 1757 SkipUntil(tok::r_paren); 1758 return ExprError(); 1759 } 1760 1761 Res = Actions.ActOnAsTypeExpr(Expr.take(), DestTy.get(), StartLoc, 1762 ConsumeParen()); 1763 break; 1764 } 1765 } 1766 1767 if (Res.isInvalid()) 1768 return ExprError(); 1769 1770 // These can be followed by postfix-expr pieces because they are 1771 // primary-expressions. 1772 return ParsePostfixExpressionSuffix(Res.take()); 1773} 1774 1775/// ParseParenExpression - This parses the unit that starts with a '(' token, 1776/// based on what is allowed by ExprType. The actual thing parsed is returned 1777/// in ExprType. If stopIfCastExpr is true, it will only return the parsed type, 1778/// not the parsed cast-expression. 1779/// 1780/// primary-expression: [C99 6.5.1] 1781/// '(' expression ')' 1782/// [GNU] '(' compound-statement ')' (if !ParenExprOnly) 1783/// postfix-expression: [C99 6.5.2] 1784/// '(' type-name ')' '{' initializer-list '}' 1785/// '(' type-name ')' '{' initializer-list ',' '}' 1786/// cast-expression: [C99 6.5.4] 1787/// '(' type-name ')' cast-expression 1788/// [ARC] bridged-cast-expression 1789/// 1790/// [ARC] bridged-cast-expression: 1791/// (__bridge type-name) cast-expression 1792/// (__bridge_transfer type-name) cast-expression 1793/// (__bridge_retained type-name) cast-expression 1794ExprResult 1795Parser::ParseParenExpression(ParenParseOption &ExprType, bool stopIfCastExpr, 1796 bool isTypeCast, ParsedType &CastTy, 1797 SourceLocation &RParenLoc) { 1798 assert(Tok.is(tok::l_paren) && "Not a paren expr!"); 1799 GreaterThanIsOperatorScope G(GreaterThanIsOperator, true); 1800 BalancedDelimiterTracker T(*this, tok::l_paren); 1801 if (T.consumeOpen()) 1802 return ExprError(); 1803 SourceLocation OpenLoc = T.getOpenLocation(); 1804 1805 ExprResult Result(true); 1806 bool isAmbiguousTypeId; 1807 CastTy = ParsedType(); 1808 1809 if (Tok.is(tok::code_completion)) { 1810 Actions.CodeCompleteOrdinaryName(getCurScope(), 1811 ExprType >= CompoundLiteral? Sema::PCC_ParenthesizedExpression 1812 : Sema::PCC_Expression); 1813 cutOffParsing(); 1814 return ExprError(); 1815 } 1816 1817 // None of these cases should fall through with an invalid Result 1818 // unless they've already reported an error. 1819 1820 if (ExprType >= CompoundStmt && Tok.is(tok::l_brace)) { 1821 Diag(Tok, diag::ext_gnu_statement_expr); 1822 ParsedAttributes attrs(AttrFactory); 1823 StmtResult Stmt(ParseCompoundStatement(attrs, true)); 1824 ExprType = CompoundStmt; 1825 1826 // If the substmt parsed correctly, build the AST node. 1827 if (!Stmt.isInvalid()) 1828 Result = Actions.ActOnStmtExpr(OpenLoc, Stmt.take(), Tok.getLocation()); 1829 } else if (ExprType >= CompoundLiteral && 1830 (Tok.is(tok::kw___bridge) || 1831 Tok.is(tok::kw___bridge_transfer) || 1832 Tok.is(tok::kw___bridge_retained) || 1833 Tok.is(tok::kw___bridge_retain))) { 1834 tok::TokenKind tokenKind = Tok.getKind(); 1835 SourceLocation BridgeKeywordLoc = ConsumeToken(); 1836 1837 // Parse an Objective-C ARC ownership cast expression. 1838 ObjCBridgeCastKind Kind; 1839 if (tokenKind == tok::kw___bridge) 1840 Kind = OBC_Bridge; 1841 else if (tokenKind == tok::kw___bridge_transfer) 1842 Kind = OBC_BridgeTransfer; 1843 else if (tokenKind == tok::kw___bridge_retained) 1844 Kind = OBC_BridgeRetained; 1845 else { 1846 // As a hopefully temporary workaround, allow __bridge_retain as 1847 // a synonym for __bridge_retained, but only in system headers. 1848 assert(tokenKind == tok::kw___bridge_retain); 1849 Kind = OBC_BridgeRetained; 1850 if (!PP.getSourceManager().isInSystemHeader(BridgeKeywordLoc)) 1851 Diag(BridgeKeywordLoc, diag::err_arc_bridge_retain) 1852 << FixItHint::CreateReplacement(BridgeKeywordLoc, 1853 "__bridge_retained"); 1854 } 1855 1856 TypeResult Ty = ParseTypeName(); 1857 T.consumeClose(); 1858 RParenLoc = T.getCloseLocation(); 1859 ExprResult SubExpr = ParseCastExpression(/*isUnaryExpression=*/false); 1860 1861 if (Ty.isInvalid() || SubExpr.isInvalid()) 1862 return ExprError(); 1863 1864 return Actions.ActOnObjCBridgedCast(getCurScope(), OpenLoc, Kind, 1865 BridgeKeywordLoc, Ty.get(), 1866 RParenLoc, SubExpr.get()); 1867 } else if (ExprType >= CompoundLiteral && 1868 isTypeIdInParens(isAmbiguousTypeId)) { 1869 1870 // Otherwise, this is a compound literal expression or cast expression. 1871 1872 // In C++, if the type-id is ambiguous we disambiguate based on context. 1873 // If stopIfCastExpr is true the context is a typeof/sizeof/alignof 1874 // in which case we should treat it as type-id. 1875 // if stopIfCastExpr is false, we need to determine the context past the 1876 // parens, so we defer to ParseCXXAmbiguousParenExpression for that. 1877 if (isAmbiguousTypeId && !stopIfCastExpr) { 1878 ExprResult res = ParseCXXAmbiguousParenExpression(ExprType, CastTy, T); 1879 RParenLoc = T.getCloseLocation(); 1880 return res; 1881 } 1882 1883 // Parse the type declarator. 1884 DeclSpec DS(AttrFactory); 1885 ParseSpecifierQualifierList(DS); 1886 Declarator DeclaratorInfo(DS, Declarator::TypeNameContext); 1887 ParseDeclarator(DeclaratorInfo); 1888 1889 // If our type is followed by an identifier and either ':' or ']', then 1890 // this is probably an Objective-C message send where the leading '[' is 1891 // missing. Recover as if that were the case. 1892 if (!DeclaratorInfo.isInvalidType() && Tok.is(tok::identifier) && 1893 !InMessageExpression && getLang().ObjC1 && 1894 (NextToken().is(tok::colon) || NextToken().is(tok::r_square))) { 1895 TypeResult Ty; 1896 { 1897 InMessageExpressionRAIIObject InMessage(*this, false); 1898 Ty = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo); 1899 } 1900 Result = ParseObjCMessageExpressionBody(SourceLocation(), 1901 SourceLocation(), 1902 Ty.get(), 0); 1903 } else { 1904 // Match the ')'. 1905 T.consumeClose(); 1906 RParenLoc = T.getCloseLocation(); 1907 if (Tok.is(tok::l_brace)) { 1908 ExprType = CompoundLiteral; 1909 TypeResult Ty; 1910 { 1911 InMessageExpressionRAIIObject InMessage(*this, false); 1912 Ty = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo); 1913 } 1914 return ParseCompoundLiteralExpression(Ty.get(), OpenLoc, RParenLoc); 1915 } 1916 1917 if (ExprType == CastExpr) { 1918 // We parsed '(' type-name ')' and the thing after it wasn't a '{'. 1919 1920 if (DeclaratorInfo.isInvalidType()) 1921 return ExprError(); 1922 1923 // Note that this doesn't parse the subsequent cast-expression, it just 1924 // returns the parsed type to the callee. 1925 if (stopIfCastExpr) { 1926 TypeResult Ty; 1927 { 1928 InMessageExpressionRAIIObject InMessage(*this, false); 1929 Ty = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo); 1930 } 1931 CastTy = Ty.get(); 1932 return ExprResult(); 1933 } 1934 1935 // Reject the cast of super idiom in ObjC. 1936 if (Tok.is(tok::identifier) && getLang().ObjC1 && 1937 Tok.getIdentifierInfo() == Ident_super && 1938 getCurScope()->isInObjcMethodScope() && 1939 GetLookAheadToken(1).isNot(tok::period)) { 1940 Diag(Tok.getLocation(), diag::err_illegal_super_cast) 1941 << SourceRange(OpenLoc, RParenLoc); 1942 return ExprError(); 1943 } 1944 1945 // Parse the cast-expression that follows it next. 1946 // TODO: For cast expression with CastTy. 1947 Result = ParseCastExpression(/*isUnaryExpression=*/false, 1948 /*isAddressOfOperand=*/false, 1949 /*isTypeCast=*/true); 1950 if (!Result.isInvalid()) { 1951 Result = Actions.ActOnCastExpr(getCurScope(), OpenLoc, 1952 DeclaratorInfo, CastTy, 1953 RParenLoc, Result.take()); 1954 } 1955 return move(Result); 1956 } 1957 1958 Diag(Tok, diag::err_expected_lbrace_in_compound_literal); 1959 return ExprError(); 1960 } 1961 } else if (isTypeCast) { 1962 // Parse the expression-list. 1963 InMessageExpressionRAIIObject InMessage(*this, false); 1964 1965 ExprVector ArgExprs(Actions); 1966 CommaLocsTy CommaLocs; 1967 1968 if (!ParseExpressionList(ArgExprs, CommaLocs)) { 1969 ExprType = SimpleExpr; 1970 Result = Actions.ActOnParenOrParenListExpr(OpenLoc, Tok.getLocation(), 1971 move_arg(ArgExprs)); 1972 } 1973 } else { 1974 InMessageExpressionRAIIObject InMessage(*this, false); 1975 1976 Result = ParseExpression(); 1977 ExprType = SimpleExpr; 1978 1979 // Don't build a paren expression unless we actually match a ')'. 1980 if (!Result.isInvalid() && Tok.is(tok::r_paren)) 1981 Result = Actions.ActOnParenExpr(OpenLoc, Tok.getLocation(), Result.take()); 1982 } 1983 1984 // Match the ')'. 1985 if (Result.isInvalid()) { 1986 SkipUntil(tok::r_paren); 1987 return ExprError(); 1988 } 1989 1990 T.consumeClose(); 1991 RParenLoc = T.getCloseLocation(); 1992 return move(Result); 1993} 1994 1995/// ParseCompoundLiteralExpression - We have parsed the parenthesized type-name 1996/// and we are at the left brace. 1997/// 1998/// postfix-expression: [C99 6.5.2] 1999/// '(' type-name ')' '{' initializer-list '}' 2000/// '(' type-name ')' '{' initializer-list ',' '}' 2001/// 2002ExprResult 2003Parser::ParseCompoundLiteralExpression(ParsedType Ty, 2004 SourceLocation LParenLoc, 2005 SourceLocation RParenLoc) { 2006 assert(Tok.is(tok::l_brace) && "Not a compound literal!"); 2007 if (!getLang().C99) // Compound literals don't exist in C90. 2008 Diag(LParenLoc, diag::ext_c99_compound_literal); 2009 ExprResult Result = ParseInitializer(); 2010 if (!Result.isInvalid() && Ty) 2011 return Actions.ActOnCompoundLiteral(LParenLoc, Ty, RParenLoc, Result.take()); 2012 return move(Result); 2013} 2014 2015/// ParseStringLiteralExpression - This handles the various token types that 2016/// form string literals, and also handles string concatenation [C99 5.1.1.2, 2017/// translation phase #6]. 2018/// 2019/// primary-expression: [C99 6.5.1] 2020/// string-literal 2021ExprResult Parser::ParseStringLiteralExpression() { 2022 assert(isTokenStringLiteral() && "Not a string literal!"); 2023 2024 // String concat. Note that keywords like __func__ and __FUNCTION__ are not 2025 // considered to be strings for concatenation purposes. 2026 SmallVector<Token, 4> StringToks; 2027 2028 do { 2029 StringToks.push_back(Tok); 2030 ConsumeStringToken(); 2031 } while (isTokenStringLiteral()); 2032 2033 // Pass the set of string tokens, ready for concatenation, to the actions. 2034 return Actions.ActOnStringLiteral(&StringToks[0], StringToks.size()); 2035} 2036 2037/// ParseGenericSelectionExpression - Parse a C1X generic-selection 2038/// [C1X 6.5.1.1]. 2039/// 2040/// generic-selection: 2041/// _Generic ( assignment-expression , generic-assoc-list ) 2042/// generic-assoc-list: 2043/// generic-association 2044/// generic-assoc-list , generic-association 2045/// generic-association: 2046/// type-name : assignment-expression 2047/// default : assignment-expression 2048ExprResult Parser::ParseGenericSelectionExpression() { 2049 assert(Tok.is(tok::kw__Generic) && "_Generic keyword expected"); 2050 SourceLocation KeyLoc = ConsumeToken(); 2051 2052 if (!getLang().C1X) 2053 Diag(KeyLoc, diag::ext_c1x_generic_selection); 2054 2055 BalancedDelimiterTracker T(*this, tok::l_paren); 2056 if (T.expectAndConsume(diag::err_expected_lparen)) 2057 return ExprError(); 2058 2059 ExprResult ControllingExpr; 2060 { 2061 // C1X 6.5.1.1p3 "The controlling expression of a generic selection is 2062 // not evaluated." 2063 EnterExpressionEvaluationContext Unevaluated(Actions, Sema::Unevaluated); 2064 ControllingExpr = ParseAssignmentExpression(); 2065 if (ControllingExpr.isInvalid()) { 2066 SkipUntil(tok::r_paren); 2067 return ExprError(); 2068 } 2069 } 2070 2071 if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "")) { 2072 SkipUntil(tok::r_paren); 2073 return ExprError(); 2074 } 2075 2076 SourceLocation DefaultLoc; 2077 TypeVector Types(Actions); 2078 ExprVector Exprs(Actions); 2079 while (1) { 2080 ParsedType Ty; 2081 if (Tok.is(tok::kw_default)) { 2082 // C1X 6.5.1.1p2 "A generic selection shall have no more than one default 2083 // generic association." 2084 if (!DefaultLoc.isInvalid()) { 2085 Diag(Tok, diag::err_duplicate_default_assoc); 2086 Diag(DefaultLoc, diag::note_previous_default_assoc); 2087 SkipUntil(tok::r_paren); 2088 return ExprError(); 2089 } 2090 DefaultLoc = ConsumeToken(); 2091 Ty = ParsedType(); 2092 } else { 2093 ColonProtectionRAIIObject X(*this); 2094 TypeResult TR = ParseTypeName(); 2095 if (TR.isInvalid()) { 2096 SkipUntil(tok::r_paren); 2097 return ExprError(); 2098 } 2099 Ty = TR.release(); 2100 } 2101 Types.push_back(Ty); 2102 2103 if (ExpectAndConsume(tok::colon, diag::err_expected_colon, "")) { 2104 SkipUntil(tok::r_paren); 2105 return ExprError(); 2106 } 2107 2108 // FIXME: These expressions should be parsed in a potentially potentially 2109 // evaluated context. 2110 ExprResult ER(ParseAssignmentExpression()); 2111 if (ER.isInvalid()) { 2112 SkipUntil(tok::r_paren); 2113 return ExprError(); 2114 } 2115 Exprs.push_back(ER.release()); 2116 2117 if (Tok.isNot(tok::comma)) 2118 break; 2119 ConsumeToken(); 2120 } 2121 2122 T.consumeClose(); 2123 if (T.getCloseLocation().isInvalid()) 2124 return ExprError(); 2125 2126 return Actions.ActOnGenericSelectionExpr(KeyLoc, DefaultLoc, 2127 T.getCloseLocation(), 2128 ControllingExpr.release(), 2129 move_arg(Types), move_arg(Exprs)); 2130} 2131 2132/// ParseExpressionList - Used for C/C++ (argument-)expression-list. 2133/// 2134/// argument-expression-list: 2135/// assignment-expression 2136/// argument-expression-list , assignment-expression 2137/// 2138/// [C++] expression-list: 2139/// [C++] assignment-expression 2140/// [C++] expression-list , assignment-expression 2141/// 2142/// [C++0x] expression-list: 2143/// [C++0x] initializer-list 2144/// 2145/// [C++0x] initializer-list 2146/// [C++0x] initializer-clause ...[opt] 2147/// [C++0x] initializer-list , initializer-clause ...[opt] 2148/// 2149/// [C++0x] initializer-clause: 2150/// [C++0x] assignment-expression 2151/// [C++0x] braced-init-list 2152/// 2153bool Parser::ParseExpressionList(SmallVectorImpl<Expr*> &Exprs, 2154 SmallVectorImpl<SourceLocation> &CommaLocs, 2155 void (Sema::*Completer)(Scope *S, 2156 Expr *Data, 2157 Expr **Args, 2158 unsigned NumArgs), 2159 Expr *Data) { 2160 while (1) { 2161 if (Tok.is(tok::code_completion)) { 2162 if (Completer) 2163 (Actions.*Completer)(getCurScope(), Data, Exprs.data(), Exprs.size()); 2164 else 2165 Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Expression); 2166 cutOffParsing(); 2167 return true; 2168 } 2169 2170 ExprResult Expr; 2171 if (getLang().CPlusPlus0x && Tok.is(tok::l_brace)) { 2172 Diag(Tok, diag::warn_cxx98_compat_generalized_initializer_lists); 2173 Expr = ParseBraceInitializer(); 2174 } else 2175 Expr = ParseAssignmentExpression(); 2176 2177 if (Tok.is(tok::ellipsis)) 2178 Expr = Actions.ActOnPackExpansion(Expr.get(), ConsumeToken()); 2179 if (Expr.isInvalid()) 2180 return true; 2181 2182 Exprs.push_back(Expr.release()); 2183 2184 if (Tok.isNot(tok::comma)) 2185 return false; 2186 // Move to the next argument, remember where the comma was. 2187 CommaLocs.push_back(ConsumeToken()); 2188 } 2189} 2190 2191/// ParseBlockId - Parse a block-id, which roughly looks like int (int x). 2192/// 2193/// [clang] block-id: 2194/// [clang] specifier-qualifier-list block-declarator 2195/// 2196void Parser::ParseBlockId() { 2197 if (Tok.is(tok::code_completion)) { 2198 Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Type); 2199 return cutOffParsing(); 2200 } 2201 2202 // Parse the specifier-qualifier-list piece. 2203 DeclSpec DS(AttrFactory); 2204 ParseSpecifierQualifierList(DS); 2205 2206 // Parse the block-declarator. 2207 Declarator DeclaratorInfo(DS, Declarator::BlockLiteralContext); 2208 ParseDeclarator(DeclaratorInfo); 2209 2210 // We do this for: ^ __attribute__((noreturn)) {, as DS has the attributes. 2211 DeclaratorInfo.takeAttributes(DS.getAttributes(), SourceLocation()); 2212 2213 MaybeParseGNUAttributes(DeclaratorInfo); 2214 2215 // Inform sema that we are starting a block. 2216 Actions.ActOnBlockArguments(DeclaratorInfo, getCurScope()); 2217} 2218 2219/// ParseBlockLiteralExpression - Parse a block literal, which roughly looks 2220/// like ^(int x){ return x+1; } 2221/// 2222/// block-literal: 2223/// [clang] '^' block-args[opt] compound-statement 2224/// [clang] '^' block-id compound-statement 2225/// [clang] block-args: 2226/// [clang] '(' parameter-list ')' 2227/// 2228ExprResult Parser::ParseBlockLiteralExpression() { 2229 assert(Tok.is(tok::caret) && "block literal starts with ^"); 2230 SourceLocation CaretLoc = ConsumeToken(); 2231 2232 PrettyStackTraceLoc CrashInfo(PP.getSourceManager(), CaretLoc, 2233 "block literal parsing"); 2234 2235 // Enter a scope to hold everything within the block. This includes the 2236 // argument decls, decls within the compound expression, etc. This also 2237 // allows determining whether a variable reference inside the block is 2238 // within or outside of the block. 2239 ParseScope BlockScope(this, Scope::BlockScope | Scope::FnScope | 2240 Scope::BreakScope | Scope::ContinueScope | 2241 Scope::DeclScope); 2242 2243 // Inform sema that we are starting a block. 2244 Actions.ActOnBlockStart(CaretLoc, getCurScope()); 2245 2246 // Parse the return type if present. 2247 DeclSpec DS(AttrFactory); 2248 Declarator ParamInfo(DS, Declarator::BlockLiteralContext); 2249 // FIXME: Since the return type isn't actually parsed, it can't be used to 2250 // fill ParamInfo with an initial valid range, so do it manually. 2251 ParamInfo.SetSourceRange(SourceRange(Tok.getLocation(), Tok.getLocation())); 2252 2253 // If this block has arguments, parse them. There is no ambiguity here with 2254 // the expression case, because the expression case requires a parameter list. 2255 if (Tok.is(tok::l_paren)) { 2256 ParseParenDeclarator(ParamInfo); 2257 // Parse the pieces after the identifier as if we had "int(...)". 2258 // SetIdentifier sets the source range end, but in this case we're past 2259 // that location. 2260 SourceLocation Tmp = ParamInfo.getSourceRange().getEnd(); 2261 ParamInfo.SetIdentifier(0, CaretLoc); 2262 ParamInfo.SetRangeEnd(Tmp); 2263 if (ParamInfo.isInvalidType()) { 2264 // If there was an error parsing the arguments, they may have 2265 // tried to use ^(x+y) which requires an argument list. Just 2266 // skip the whole block literal. 2267 Actions.ActOnBlockError(CaretLoc, getCurScope()); 2268 return ExprError(); 2269 } 2270 2271 MaybeParseGNUAttributes(ParamInfo); 2272 2273 // Inform sema that we are starting a block. 2274 Actions.ActOnBlockArguments(ParamInfo, getCurScope()); 2275 } else if (!Tok.is(tok::l_brace)) { 2276 ParseBlockId(); 2277 } else { 2278 // Otherwise, pretend we saw (void). 2279 ParsedAttributes attrs(AttrFactory); 2280 ParamInfo.AddTypeInfo(DeclaratorChunk::getFunction(true, false, 2281 SourceLocation(), 2282 0, 0, 0, 2283 true, SourceLocation(), 2284 SourceLocation(), 2285 SourceLocation(), 2286 SourceLocation(), 2287 EST_None, 2288 SourceLocation(), 2289 0, 0, 0, 0, 2290 CaretLoc, CaretLoc, 2291 ParamInfo), 2292 attrs, CaretLoc); 2293 2294 MaybeParseGNUAttributes(ParamInfo); 2295 2296 // Inform sema that we are starting a block. 2297 Actions.ActOnBlockArguments(ParamInfo, getCurScope()); 2298 } 2299 2300 2301 ExprResult Result(true); 2302 if (!Tok.is(tok::l_brace)) { 2303 // Saw something like: ^expr 2304 Diag(Tok, diag::err_expected_expression); 2305 Actions.ActOnBlockError(CaretLoc, getCurScope()); 2306 return ExprError(); 2307 } 2308 2309 StmtResult Stmt(ParseCompoundStatementBody()); 2310 BlockScope.Exit(); 2311 if (!Stmt.isInvalid()) 2312 Result = Actions.ActOnBlockStmtExpr(CaretLoc, Stmt.take(), getCurScope()); 2313 else 2314 Actions.ActOnBlockError(CaretLoc, getCurScope()); 2315 return move(Result); 2316} 2317