ParseExpr.cpp revision 4a8dfb511e8f84b2e38b7a86d8ddf05ac1e1a41b
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 return Actions.ActOnCXXNullPtrLiteral(ConsumeToken()); 658 659 case tok::annot_primary_expr: 660 assert(Res.get() == 0 && "Stray primary-expression annotation?"); 661 Res = getExprAnnotation(Tok); 662 ConsumeToken(); 663 break; 664 665 case tok::identifier: { // primary-expression: identifier 666 // unqualified-id: identifier 667 // constant: enumeration-constant 668 // Turn a potentially qualified name into a annot_typename or 669 // annot_cxxscope if it would be valid. This handles things like x::y, etc. 670 if (getLang().CPlusPlus) { 671 // Avoid the unnecessary parse-time lookup in the common case 672 // where the syntax forbids a type. 673 const Token &Next = NextToken(); 674 if (Next.is(tok::coloncolon) || 675 (!ColonIsSacred && Next.is(tok::colon)) || 676 Next.is(tok::less) || 677 Next.is(tok::l_paren)) { 678 // If TryAnnotateTypeOrScopeToken annotates the token, tail recurse. 679 if (TryAnnotateTypeOrScopeToken()) 680 return ExprError(); 681 if (!Tok.is(tok::identifier)) 682 return ParseCastExpression(isUnaryExpression, isAddressOfOperand); 683 } 684 } 685 686 // Consume the identifier so that we can see if it is followed by a '(' or 687 // '.'. 688 IdentifierInfo &II = *Tok.getIdentifierInfo(); 689 SourceLocation ILoc = ConsumeToken(); 690 691 // Support 'Class.property' and 'super.property' notation. 692 if (getLang().ObjC1 && Tok.is(tok::period) && 693 (Actions.getTypeName(II, ILoc, getCurScope()) || 694 // Allow the base to be 'super' if in an objc-method. 695 (&II == Ident_super && getCurScope()->isInObjcMethodScope()))) { 696 ConsumeToken(); 697 698 if (Tok.isNot(tok::identifier)) { 699 Diag(Tok, diag::err_expected_property_name); 700 return ExprError(); 701 } 702 IdentifierInfo &PropertyName = *Tok.getIdentifierInfo(); 703 SourceLocation PropertyLoc = ConsumeToken(); 704 705 Res = Actions.ActOnClassPropertyRefExpr(II, PropertyName, 706 ILoc, PropertyLoc); 707 break; 708 } 709 710 // In an Objective-C method, if we have "super" followed by an identifier, 711 // the token sequence is ill-formed. However, if there's a ':' or ']' after 712 // that identifier, this is probably a message send with a missing open 713 // bracket. Treat it as such. 714 if (getLang().ObjC1 && &II == Ident_super && !InMessageExpression && 715 getCurScope()->isInObjcMethodScope() && 716 ((Tok.is(tok::identifier) && 717 (NextToken().is(tok::colon) || NextToken().is(tok::r_square))) || 718 Tok.is(tok::code_completion))) { 719 Res = ParseObjCMessageExpressionBody(SourceLocation(), ILoc, ParsedType(), 720 0); 721 break; 722 } 723 724 // If we have an Objective-C class name followed by an identifier 725 // and either ':' or ']', this is an Objective-C class message 726 // send that's missing the opening '['. Recovery 727 // appropriately. Also take this path if we're performing code 728 // completion after an Objective-C class name. 729 if (getLang().ObjC1 && 730 ((Tok.is(tok::identifier) && !InMessageExpression) || 731 Tok.is(tok::code_completion))) { 732 const Token& Next = NextToken(); 733 if (Tok.is(tok::code_completion) || 734 Next.is(tok::colon) || Next.is(tok::r_square)) 735 if (ParsedType Typ = Actions.getTypeName(II, ILoc, getCurScope())) 736 if (Typ.get()->isObjCObjectOrInterfaceType()) { 737 // Fake up a Declarator to use with ActOnTypeName. 738 DeclSpec DS(AttrFactory); 739 DS.SetRangeStart(ILoc); 740 DS.SetRangeEnd(ILoc); 741 const char *PrevSpec = 0; 742 unsigned DiagID; 743 DS.SetTypeSpecType(TST_typename, ILoc, PrevSpec, DiagID, Typ); 744 745 Declarator DeclaratorInfo(DS, Declarator::TypeNameContext); 746 TypeResult Ty = Actions.ActOnTypeName(getCurScope(), 747 DeclaratorInfo); 748 if (Ty.isInvalid()) 749 break; 750 751 Res = ParseObjCMessageExpressionBody(SourceLocation(), 752 SourceLocation(), 753 Ty.get(), 0); 754 break; 755 } 756 } 757 758 // Make sure to pass down the right value for isAddressOfOperand. 759 if (isAddressOfOperand && isPostfixExpressionSuffixStart()) 760 isAddressOfOperand = false; 761 762 // Function designators are allowed to be undeclared (C99 6.5.1p2), so we 763 // need to know whether or not this identifier is a function designator or 764 // not. 765 UnqualifiedId Name; 766 CXXScopeSpec ScopeSpec; 767 Name.setIdentifier(&II, ILoc); 768 Res = Actions.ActOnIdExpression(getCurScope(), ScopeSpec, Name, 769 Tok.is(tok::l_paren), isAddressOfOperand); 770 break; 771 } 772 case tok::char_constant: // constant: character-constant 773 case tok::wide_char_constant: 774 case tok::utf16_char_constant: 775 case tok::utf32_char_constant: 776 Res = Actions.ActOnCharacterConstant(Tok); 777 ConsumeToken(); 778 break; 779 case tok::kw___func__: // primary-expression: __func__ [C99 6.4.2.2] 780 case tok::kw___FUNCTION__: // primary-expression: __FUNCTION__ [GNU] 781 case tok::kw___PRETTY_FUNCTION__: // primary-expression: __P..Y_F..N__ [GNU] 782 Res = Actions.ActOnPredefinedExpr(Tok.getLocation(), SavedKind); 783 ConsumeToken(); 784 break; 785 case tok::string_literal: // primary-expression: string-literal 786 case tok::wide_string_literal: 787 case tok::utf8_string_literal: 788 case tok::utf16_string_literal: 789 case tok::utf32_string_literal: 790 Res = ParseStringLiteralExpression(); 791 break; 792 case tok::kw__Generic: // primary-expression: generic-selection [C1X 6.5.1] 793 Res = ParseGenericSelectionExpression(); 794 break; 795 case tok::kw___builtin_va_arg: 796 case tok::kw___builtin_offsetof: 797 case tok::kw___builtin_choose_expr: 798 case tok::kw___builtin_astype: // primary-expression: [OCL] as_type() 799 return ParseBuiltinPrimaryExpression(); 800 case tok::kw___null: 801 return Actions.ActOnGNUNullExpr(ConsumeToken()); 802 803 case tok::plusplus: // unary-expression: '++' unary-expression [C99] 804 case tok::minusminus: { // unary-expression: '--' unary-expression [C99] 805 // C++ [expr.unary] has: 806 // unary-expression: 807 // ++ cast-expression 808 // -- cast-expression 809 SourceLocation SavedLoc = ConsumeToken(); 810 Res = ParseCastExpression(!getLang().CPlusPlus); 811 if (!Res.isInvalid()) 812 Res = Actions.ActOnUnaryOp(getCurScope(), SavedLoc, SavedKind, Res.get()); 813 return move(Res); 814 } 815 case tok::amp: { // unary-expression: '&' cast-expression 816 // Special treatment because of member pointers 817 SourceLocation SavedLoc = ConsumeToken(); 818 Res = ParseCastExpression(false, true); 819 if (!Res.isInvalid()) 820 Res = Actions.ActOnUnaryOp(getCurScope(), SavedLoc, SavedKind, Res.get()); 821 return move(Res); 822 } 823 824 case tok::star: // unary-expression: '*' cast-expression 825 case tok::plus: // unary-expression: '+' cast-expression 826 case tok::minus: // unary-expression: '-' cast-expression 827 case tok::tilde: // unary-expression: '~' cast-expression 828 case tok::exclaim: // unary-expression: '!' cast-expression 829 case tok::kw___real: // unary-expression: '__real' cast-expression [GNU] 830 case tok::kw___imag: { // unary-expression: '__imag' cast-expression [GNU] 831 SourceLocation SavedLoc = ConsumeToken(); 832 Res = ParseCastExpression(false); 833 if (!Res.isInvalid()) 834 Res = Actions.ActOnUnaryOp(getCurScope(), SavedLoc, SavedKind, Res.get()); 835 return move(Res); 836 } 837 838 case tok::kw___extension__:{//unary-expression:'__extension__' cast-expr [GNU] 839 // __extension__ silences extension warnings in the subexpression. 840 ExtensionRAIIObject O(Diags); // Use RAII to do this. 841 SourceLocation SavedLoc = ConsumeToken(); 842 Res = ParseCastExpression(false); 843 if (!Res.isInvalid()) 844 Res = Actions.ActOnUnaryOp(getCurScope(), SavedLoc, SavedKind, Res.get()); 845 return move(Res); 846 } 847 case tok::kw_sizeof: // unary-expression: 'sizeof' unary-expression 848 // unary-expression: 'sizeof' '(' type-name ')' 849 case tok::kw_alignof: 850 case tok::kw___alignof: // unary-expression: '__alignof' unary-expression 851 // unary-expression: '__alignof' '(' type-name ')' 852 // unary-expression: 'alignof' '(' type-id ')' 853 case tok::kw_vec_step: // unary-expression: OpenCL 'vec_step' expression 854 return ParseUnaryExprOrTypeTraitExpression(); 855 case tok::ampamp: { // unary-expression: '&&' identifier 856 SourceLocation AmpAmpLoc = ConsumeToken(); 857 if (Tok.isNot(tok::identifier)) 858 return ExprError(Diag(Tok, diag::err_expected_ident)); 859 860 if (getCurScope()->getFnParent() == 0) 861 return ExprError(Diag(Tok, diag::err_address_of_label_outside_fn)); 862 863 Diag(AmpAmpLoc, diag::ext_gnu_address_of_label); 864 LabelDecl *LD = Actions.LookupOrCreateLabel(Tok.getIdentifierInfo(), 865 Tok.getLocation()); 866 Res = Actions.ActOnAddrLabel(AmpAmpLoc, Tok.getLocation(), LD); 867 ConsumeToken(); 868 return move(Res); 869 } 870 case tok::kw_const_cast: 871 case tok::kw_dynamic_cast: 872 case tok::kw_reinterpret_cast: 873 case tok::kw_static_cast: 874 Res = ParseCXXCasts(); 875 break; 876 case tok::kw_typeid: 877 Res = ParseCXXTypeid(); 878 break; 879 case tok::kw___uuidof: 880 Res = ParseCXXUuidof(); 881 break; 882 case tok::kw_this: 883 Res = ParseCXXThis(); 884 break; 885 886 case tok::annot_typename: 887 if (isStartOfObjCClassMessageMissingOpenBracket()) { 888 ParsedType Type = getTypeAnnotation(Tok); 889 890 // Fake up a Declarator to use with ActOnTypeName. 891 DeclSpec DS(AttrFactory); 892 DS.SetRangeStart(Tok.getLocation()); 893 DS.SetRangeEnd(Tok.getLastLoc()); 894 895 const char *PrevSpec = 0; 896 unsigned DiagID; 897 DS.SetTypeSpecType(TST_typename, Tok.getAnnotationEndLoc(), 898 PrevSpec, DiagID, Type); 899 900 Declarator DeclaratorInfo(DS, Declarator::TypeNameContext); 901 TypeResult Ty = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo); 902 if (Ty.isInvalid()) 903 break; 904 905 ConsumeToken(); 906 Res = ParseObjCMessageExpressionBody(SourceLocation(), SourceLocation(), 907 Ty.get(), 0); 908 break; 909 } 910 // Fall through 911 912 case tok::kw_char: 913 case tok::kw_wchar_t: 914 case tok::kw_char16_t: 915 case tok::kw_char32_t: 916 case tok::kw_bool: 917 case tok::kw_short: 918 case tok::kw_int: 919 case tok::kw_long: 920 case tok::kw___int64: 921 case tok::kw_signed: 922 case tok::kw_unsigned: 923 case tok::kw_float: 924 case tok::kw_double: 925 case tok::kw_void: 926 case tok::kw_typename: 927 case tok::kw_typeof: 928 case tok::kw___vector: { 929 if (!getLang().CPlusPlus) { 930 Diag(Tok, diag::err_expected_expression); 931 return ExprError(); 932 } 933 934 if (SavedKind == tok::kw_typename) { 935 // postfix-expression: typename-specifier '(' expression-list[opt] ')' 936 // typename-specifier braced-init-list 937 if (TryAnnotateTypeOrScopeToken()) 938 return ExprError(); 939 } 940 941 // postfix-expression: simple-type-specifier '(' expression-list[opt] ')' 942 // simple-type-specifier braced-init-list 943 // 944 DeclSpec DS(AttrFactory); 945 ParseCXXSimpleTypeSpecifier(DS); 946 if (Tok.isNot(tok::l_paren) && 947 (!getLang().CPlusPlus0x || Tok.isNot(tok::l_brace))) 948 return ExprError(Diag(Tok, diag::err_expected_lparen_after_type) 949 << DS.getSourceRange()); 950 951 Res = ParseCXXTypeConstructExpression(DS); 952 break; 953 } 954 955 case tok::annot_cxxscope: { // [C++] id-expression: qualified-id 956 // If TryAnnotateTypeOrScopeToken annotates the token, tail recurse. 957 // (We can end up in this situation after tentative parsing.) 958 if (TryAnnotateTypeOrScopeToken()) 959 return ExprError(); 960 if (!Tok.is(tok::annot_cxxscope)) 961 return ParseCastExpression(isUnaryExpression, isAddressOfOperand, 962 NotCastExpr, isTypeCast); 963 964 Token Next = NextToken(); 965 if (Next.is(tok::annot_template_id)) { 966 TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Next); 967 if (TemplateId->Kind == TNK_Type_template) { 968 // We have a qualified template-id that we know refers to a 969 // type, translate it into a type and continue parsing as a 970 // cast expression. 971 CXXScopeSpec SS; 972 ParseOptionalCXXScopeSpecifier(SS, ParsedType(), false); 973 AnnotateTemplateIdTokenAsType(); 974 return ParseCastExpression(isUnaryExpression, isAddressOfOperand, 975 NotCastExpr, isTypeCast); 976 } 977 } 978 979 // Parse as an id-expression. 980 Res = ParseCXXIdExpression(isAddressOfOperand); 981 break; 982 } 983 984 case tok::annot_template_id: { // [C++] template-id 985 TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Tok); 986 if (TemplateId->Kind == TNK_Type_template) { 987 // We have a template-id that we know refers to a type, 988 // translate it into a type and continue parsing as a cast 989 // expression. 990 AnnotateTemplateIdTokenAsType(); 991 return ParseCastExpression(isUnaryExpression, isAddressOfOperand, 992 NotCastExpr, isTypeCast); 993 } 994 995 // Fall through to treat the template-id as an id-expression. 996 } 997 998 case tok::kw_operator: // [C++] id-expression: operator/conversion-function-id 999 Res = ParseCXXIdExpression(isAddressOfOperand); 1000 break; 1001 1002 case tok::coloncolon: { 1003 // ::foo::bar -> global qualified name etc. If TryAnnotateTypeOrScopeToken 1004 // annotates the token, tail recurse. 1005 if (TryAnnotateTypeOrScopeToken()) 1006 return ExprError(); 1007 if (!Tok.is(tok::coloncolon)) 1008 return ParseCastExpression(isUnaryExpression, isAddressOfOperand); 1009 1010 // ::new -> [C++] new-expression 1011 // ::delete -> [C++] delete-expression 1012 SourceLocation CCLoc = ConsumeToken(); 1013 if (Tok.is(tok::kw_new)) 1014 return ParseCXXNewExpression(true, CCLoc); 1015 if (Tok.is(tok::kw_delete)) 1016 return ParseCXXDeleteExpression(true, CCLoc); 1017 1018 // This is not a type name or scope specifier, it is an invalid expression. 1019 Diag(CCLoc, diag::err_expected_expression); 1020 return ExprError(); 1021 } 1022 1023 case tok::kw_new: // [C++] new-expression 1024 return ParseCXXNewExpression(false, Tok.getLocation()); 1025 1026 case tok::kw_delete: // [C++] delete-expression 1027 return ParseCXXDeleteExpression(false, Tok.getLocation()); 1028 1029 case tok::kw_noexcept: { // [C++0x] 'noexcept' '(' expression ')' 1030 SourceLocation KeyLoc = ConsumeToken(); 1031 BalancedDelimiterTracker T(*this, tok::l_paren); 1032 1033 if (T.expectAndConsume(diag::err_expected_lparen_after, "noexcept")) 1034 return ExprError(); 1035 // C++ [expr.unary.noexcept]p1: 1036 // The noexcept operator determines whether the evaluation of its operand, 1037 // which is an unevaluated operand, can throw an exception. 1038 EnterExpressionEvaluationContext Unevaluated(Actions, Sema::Unevaluated); 1039 ExprResult Result = ParseExpression(); 1040 1041 T.consumeClose(); 1042 1043 if (!Result.isInvalid()) 1044 Result = Actions.ActOnNoexceptExpr(KeyLoc, T.getOpenLocation(), 1045 Result.take(), T.getCloseLocation()); 1046 return move(Result); 1047 } 1048 1049 case tok::kw___is_abstract: // [GNU] unary-type-trait 1050 case tok::kw___is_class: 1051 case tok::kw___is_empty: 1052 case tok::kw___is_enum: 1053 case tok::kw___is_literal: 1054 case tok::kw___is_arithmetic: 1055 case tok::kw___is_integral: 1056 case tok::kw___is_floating_point: 1057 case tok::kw___is_complete_type: 1058 case tok::kw___is_void: 1059 case tok::kw___is_array: 1060 case tok::kw___is_function: 1061 case tok::kw___is_reference: 1062 case tok::kw___is_lvalue_reference: 1063 case tok::kw___is_rvalue_reference: 1064 case tok::kw___is_fundamental: 1065 case tok::kw___is_object: 1066 case tok::kw___is_scalar: 1067 case tok::kw___is_compound: 1068 case tok::kw___is_pointer: 1069 case tok::kw___is_member_object_pointer: 1070 case tok::kw___is_member_function_pointer: 1071 case tok::kw___is_member_pointer: 1072 case tok::kw___is_const: 1073 case tok::kw___is_volatile: 1074 case tok::kw___is_standard_layout: 1075 case tok::kw___is_signed: 1076 case tok::kw___is_unsigned: 1077 case tok::kw___is_literal_type: 1078 case tok::kw___is_pod: 1079 case tok::kw___is_polymorphic: 1080 case tok::kw___is_trivial: 1081 case tok::kw___is_trivially_copyable: 1082 case tok::kw___is_union: 1083 case tok::kw___has_trivial_constructor: 1084 case tok::kw___has_trivial_copy: 1085 case tok::kw___has_trivial_assign: 1086 case tok::kw___has_trivial_destructor: 1087 case tok::kw___has_nothrow_assign: 1088 case tok::kw___has_nothrow_copy: 1089 case tok::kw___has_nothrow_constructor: 1090 case tok::kw___has_virtual_destructor: 1091 return ParseUnaryTypeTrait(); 1092 1093 case tok::kw___builtin_types_compatible_p: 1094 case tok::kw___is_base_of: 1095 case tok::kw___is_same: 1096 case tok::kw___is_convertible: 1097 case tok::kw___is_convertible_to: 1098 return ParseBinaryTypeTrait(); 1099 1100 case tok::kw___array_rank: 1101 case tok::kw___array_extent: 1102 return ParseArrayTypeTrait(); 1103 1104 case tok::kw___is_lvalue_expr: 1105 case tok::kw___is_rvalue_expr: 1106 return ParseExpressionTrait(); 1107 1108 case tok::at: { 1109 SourceLocation AtLoc = ConsumeToken(); 1110 return ParseObjCAtExpression(AtLoc); 1111 } 1112 case tok::caret: 1113 Res = ParseBlockLiteralExpression(); 1114 break; 1115 case tok::code_completion: { 1116 Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Expression); 1117 cutOffParsing(); 1118 return ExprError(); 1119 } 1120 case tok::l_square: 1121 if (getLang().CPlusPlus0x) { 1122 if (getLang().ObjC1) { 1123 Res = TryParseLambdaExpression(); 1124 if (Res.isInvalid()) 1125 Res = ParseObjCMessageExpression(); 1126 break; 1127 } 1128 Res = ParseLambdaExpression(); 1129 break; 1130 } 1131 if (getLang().ObjC1) { 1132 Res = ParseObjCMessageExpression(); 1133 break; 1134 } 1135 // FALL THROUGH. 1136 default: 1137 NotCastExpr = true; 1138 return ExprError(); 1139 } 1140 1141 // These can be followed by postfix-expr pieces. 1142 return ParsePostfixExpressionSuffix(Res); 1143} 1144 1145/// ParsePostfixExpressionSuffix - Once the leading part of a postfix-expression 1146/// is parsed, this method parses any suffixes that apply. 1147/// 1148/// postfix-expression: [C99 6.5.2] 1149/// primary-expression 1150/// postfix-expression '[' expression ']' 1151/// postfix-expression '[' braced-init-list ']' 1152/// postfix-expression '(' argument-expression-list[opt] ')' 1153/// postfix-expression '.' identifier 1154/// postfix-expression '->' identifier 1155/// postfix-expression '++' 1156/// postfix-expression '--' 1157/// '(' type-name ')' '{' initializer-list '}' 1158/// '(' type-name ')' '{' initializer-list ',' '}' 1159/// 1160/// argument-expression-list: [C99 6.5.2] 1161/// argument-expression ...[opt] 1162/// argument-expression-list ',' assignment-expression ...[opt] 1163/// 1164ExprResult 1165Parser::ParsePostfixExpressionSuffix(ExprResult LHS) { 1166 // Now that the primary-expression piece of the postfix-expression has been 1167 // parsed, see if there are any postfix-expression pieces here. 1168 SourceLocation Loc; 1169 while (1) { 1170 switch (Tok.getKind()) { 1171 case tok::code_completion: 1172 if (InMessageExpression) 1173 return move(LHS); 1174 1175 Actions.CodeCompletePostfixExpression(getCurScope(), LHS); 1176 cutOffParsing(); 1177 return ExprError(); 1178 1179 case tok::identifier: 1180 // If we see identifier: after an expression, and we're not already in a 1181 // message send, then this is probably a message send with a missing 1182 // opening bracket '['. 1183 if (getLang().ObjC1 && !InMessageExpression && 1184 (NextToken().is(tok::colon) || NextToken().is(tok::r_square))) { 1185 LHS = ParseObjCMessageExpressionBody(SourceLocation(), SourceLocation(), 1186 ParsedType(), LHS.get()); 1187 break; 1188 } 1189 1190 // Fall through; this isn't a message send. 1191 1192 default: // Not a postfix-expression suffix. 1193 return move(LHS); 1194 case tok::l_square: { // postfix-expression: p-e '[' expression ']' 1195 // If we have a array postfix expression that starts on a new line and 1196 // Objective-C is enabled, it is highly likely that the user forgot a 1197 // semicolon after the base expression and that the array postfix-expr is 1198 // actually another message send. In this case, do some look-ahead to see 1199 // if the contents of the square brackets are obviously not a valid 1200 // expression and recover by pretending there is no suffix. 1201 if (getLang().ObjC1 && Tok.isAtStartOfLine() && 1202 isSimpleObjCMessageExpression()) 1203 return move(LHS); 1204 1205 BalancedDelimiterTracker T(*this, tok::l_square); 1206 T.consumeOpen(); 1207 Loc = T.getOpenLocation(); 1208 ExprResult Idx; 1209 if (getLang().CPlusPlus0x && Tok.is(tok::l_brace)) 1210 Idx = ParseBraceInitializer(); 1211 else 1212 Idx = ParseExpression(); 1213 1214 SourceLocation RLoc = Tok.getLocation(); 1215 1216 if (!LHS.isInvalid() && !Idx.isInvalid() && Tok.is(tok::r_square)) { 1217 LHS = Actions.ActOnArraySubscriptExpr(getCurScope(), LHS.take(), Loc, 1218 Idx.take(), RLoc); 1219 } else 1220 LHS = ExprError(); 1221 1222 // Match the ']'. 1223 T.consumeClose(); 1224 break; 1225 } 1226 1227 case tok::l_paren: // p-e: p-e '(' argument-expression-list[opt] ')' 1228 case tok::lesslessless: { // p-e: p-e '<<<' argument-expression-list '>>>' 1229 // '(' argument-expression-list[opt] ')' 1230 tok::TokenKind OpKind = Tok.getKind(); 1231 InMessageExpressionRAIIObject InMessage(*this, false); 1232 1233 Expr *ExecConfig = 0; 1234 1235 BalancedDelimiterTracker LLLT(*this, tok::lesslessless); 1236 BalancedDelimiterTracker PT(*this, tok::l_paren); 1237 1238 if (OpKind == tok::lesslessless) { 1239 ExprVector ExecConfigExprs(Actions); 1240 CommaLocsTy ExecConfigCommaLocs; 1241 LLLT.consumeOpen(); 1242 1243 if (ParseExpressionList(ExecConfigExprs, ExecConfigCommaLocs)) { 1244 LHS = ExprError(); 1245 } 1246 1247 if (LHS.isInvalid()) { 1248 SkipUntil(tok::greatergreatergreater); 1249 } else if (LLLT.consumeClose()) { 1250 // There was an error closing the brackets 1251 LHS = ExprError(); 1252 } 1253 1254 if (!LHS.isInvalid()) { 1255 if (ExpectAndConsume(tok::l_paren, diag::err_expected_lparen, "")) 1256 LHS = ExprError(); 1257 else 1258 Loc = PrevTokLocation; 1259 } 1260 1261 if (!LHS.isInvalid()) { 1262 ExprResult ECResult = Actions.ActOnCUDAExecConfigExpr(getCurScope(), 1263 LLLT.getOpenLocation(), 1264 move_arg(ExecConfigExprs), 1265 LLLT.getCloseLocation()); 1266 if (ECResult.isInvalid()) 1267 LHS = ExprError(); 1268 else 1269 ExecConfig = ECResult.get(); 1270 } 1271 } else { 1272 PT.consumeOpen(); 1273 Loc = PT.getOpenLocation(); 1274 } 1275 1276 ExprVector ArgExprs(Actions); 1277 CommaLocsTy CommaLocs; 1278 1279 if (Tok.is(tok::code_completion)) { 1280 Actions.CodeCompleteCall(getCurScope(), LHS.get(), 0, 0); 1281 cutOffParsing(); 1282 return ExprError(); 1283 } 1284 1285 if (OpKind == tok::l_paren || !LHS.isInvalid()) { 1286 if (Tok.isNot(tok::r_paren)) { 1287 if (ParseExpressionList(ArgExprs, CommaLocs, &Sema::CodeCompleteCall, 1288 LHS.get())) { 1289 LHS = ExprError(); 1290 } 1291 } 1292 } 1293 1294 // Match the ')'. 1295 if (LHS.isInvalid()) { 1296 SkipUntil(tok::r_paren); 1297 } else if (Tok.isNot(tok::r_paren)) { 1298 PT.consumeClose(); 1299 LHS = ExprError(); 1300 } else { 1301 assert((ArgExprs.size() == 0 || 1302 ArgExprs.size()-1 == CommaLocs.size())&& 1303 "Unexpected number of commas!"); 1304 LHS = Actions.ActOnCallExpr(getCurScope(), LHS.take(), Loc, 1305 move_arg(ArgExprs), Tok.getLocation(), 1306 ExecConfig); 1307 PT.consumeClose(); 1308 } 1309 1310 break; 1311 } 1312 case tok::arrow: 1313 case tok::period: { 1314 // postfix-expression: p-e '->' template[opt] id-expression 1315 // postfix-expression: p-e '.' template[opt] id-expression 1316 tok::TokenKind OpKind = Tok.getKind(); 1317 SourceLocation OpLoc = ConsumeToken(); // Eat the "." or "->" token. 1318 1319 CXXScopeSpec SS; 1320 ParsedType ObjectType; 1321 bool MayBePseudoDestructor = false; 1322 if (getLang().CPlusPlus && !LHS.isInvalid()) { 1323 LHS = Actions.ActOnStartCXXMemberReference(getCurScope(), LHS.take(), 1324 OpLoc, OpKind, ObjectType, 1325 MayBePseudoDestructor); 1326 if (LHS.isInvalid()) 1327 break; 1328 1329 ParseOptionalCXXScopeSpecifier(SS, ObjectType, false, 1330 &MayBePseudoDestructor); 1331 if (SS.isNotEmpty()) 1332 ObjectType = ParsedType(); 1333 } 1334 1335 if (Tok.is(tok::code_completion)) { 1336 // Code completion for a member access expression. 1337 Actions.CodeCompleteMemberReferenceExpr(getCurScope(), LHS.get(), 1338 OpLoc, OpKind == tok::arrow); 1339 1340 cutOffParsing(); 1341 return ExprError(); 1342 } 1343 1344 if (MayBePseudoDestructor && !LHS.isInvalid()) { 1345 LHS = ParseCXXPseudoDestructor(LHS.take(), OpLoc, OpKind, SS, 1346 ObjectType); 1347 break; 1348 } 1349 1350 // Either the action has told is that this cannot be a 1351 // pseudo-destructor expression (based on the type of base 1352 // expression), or we didn't see a '~' in the right place. We 1353 // can still parse a destructor name here, but in that case it 1354 // names a real destructor. 1355 // Allow explicit constructor calls in Microsoft mode. 1356 // FIXME: Add support for explicit call of template constructor. 1357 UnqualifiedId Name; 1358 if (ParseUnqualifiedId(SS, 1359 /*EnteringContext=*/false, 1360 /*AllowDestructorName=*/true, 1361 /*AllowConstructorName=*/ getLang().MicrosoftExt, 1362 ObjectType, 1363 Name)) 1364 LHS = ExprError(); 1365 1366 if (!LHS.isInvalid()) 1367 LHS = Actions.ActOnMemberAccessExpr(getCurScope(), LHS.take(), OpLoc, 1368 OpKind, SS, Name, ObjCImpDecl, 1369 Tok.is(tok::l_paren)); 1370 break; 1371 } 1372 case tok::plusplus: // postfix-expression: postfix-expression '++' 1373 case tok::minusminus: // postfix-expression: postfix-expression '--' 1374 if (!LHS.isInvalid()) { 1375 LHS = Actions.ActOnPostfixUnaryOp(getCurScope(), Tok.getLocation(), 1376 Tok.getKind(), LHS.take()); 1377 } 1378 ConsumeToken(); 1379 break; 1380 } 1381 } 1382} 1383 1384/// ParseExprAfterUnaryExprOrTypeTrait - We parsed a typeof/sizeof/alignof/ 1385/// vec_step and we are at the start of an expression or a parenthesized 1386/// type-id. OpTok is the operand token (typeof/sizeof/alignof). Returns the 1387/// expression (isCastExpr == false) or the type (isCastExpr == true). 1388/// 1389/// unary-expression: [C99 6.5.3] 1390/// 'sizeof' unary-expression 1391/// 'sizeof' '(' type-name ')' 1392/// [GNU] '__alignof' unary-expression 1393/// [GNU] '__alignof' '(' type-name ')' 1394/// [C++0x] 'alignof' '(' type-id ')' 1395/// 1396/// [GNU] typeof-specifier: 1397/// typeof ( expressions ) 1398/// typeof ( type-name ) 1399/// [GNU/C++] typeof unary-expression 1400/// 1401/// [OpenCL 1.1 6.11.12] vec_step built-in function: 1402/// vec_step ( expressions ) 1403/// vec_step ( type-name ) 1404/// 1405ExprResult 1406Parser::ParseExprAfterUnaryExprOrTypeTrait(const Token &OpTok, 1407 bool &isCastExpr, 1408 ParsedType &CastTy, 1409 SourceRange &CastRange) { 1410 1411 assert((OpTok.is(tok::kw_typeof) || OpTok.is(tok::kw_sizeof) || 1412 OpTok.is(tok::kw___alignof) || OpTok.is(tok::kw_alignof) || 1413 OpTok.is(tok::kw_vec_step)) && 1414 "Not a typeof/sizeof/alignof/vec_step expression!"); 1415 1416 ExprResult Operand; 1417 1418 // If the operand doesn't start with an '(', it must be an expression. 1419 if (Tok.isNot(tok::l_paren)) { 1420 isCastExpr = false; 1421 if (OpTok.is(tok::kw_typeof) && !getLang().CPlusPlus) { 1422 Diag(Tok,diag::err_expected_lparen_after_id) << OpTok.getIdentifierInfo(); 1423 return ExprError(); 1424 } 1425 1426 // C++0x [expr.sizeof]p1: 1427 // [...] The operand is either an expression, which is an unevaluated 1428 // operand (Clause 5) [...] 1429 // 1430 // The GNU typeof and alignof extensions also behave as unevaluated 1431 // operands. 1432 EnterExpressionEvaluationContext Unevaluated(Actions, 1433 Sema::Unevaluated); 1434 Operand = ParseCastExpression(true/*isUnaryExpression*/); 1435 } else { 1436 // If it starts with a '(', we know that it is either a parenthesized 1437 // type-name, or it is a unary-expression that starts with a compound 1438 // literal, or starts with a primary-expression that is a parenthesized 1439 // expression. 1440 ParenParseOption ExprType = CastExpr; 1441 SourceLocation LParenLoc = Tok.getLocation(), RParenLoc; 1442 1443 // C++0x [expr.sizeof]p1: 1444 // [...] The operand is either an expression, which is an unevaluated 1445 // operand (Clause 5) [...] 1446 // 1447 // The GNU typeof and alignof extensions also behave as unevaluated 1448 // operands. 1449 EnterExpressionEvaluationContext Unevaluated(Actions, 1450 Sema::Unevaluated); 1451 Operand = ParseParenExpression(ExprType, true/*stopIfCastExpr*/, 1452 false, CastTy, RParenLoc); 1453 CastRange = SourceRange(LParenLoc, RParenLoc); 1454 1455 // If ParseParenExpression parsed a '(typename)' sequence only, then this is 1456 // a type. 1457 if (ExprType == CastExpr) { 1458 isCastExpr = true; 1459 return ExprEmpty(); 1460 } 1461 1462 if (getLang().CPlusPlus || OpTok.isNot(tok::kw_typeof)) { 1463 // GNU typeof in C requires the expression to be parenthesized. Not so for 1464 // sizeof/alignof or in C++. Therefore, the parenthesized expression is 1465 // the start of a unary-expression, but doesn't include any postfix 1466 // pieces. Parse these now if present. 1467 if (!Operand.isInvalid()) 1468 Operand = ParsePostfixExpressionSuffix(Operand.get()); 1469 } 1470 } 1471 1472 // If we get here, the operand to the typeof/sizeof/alignof was an expresion. 1473 isCastExpr = false; 1474 return move(Operand); 1475} 1476 1477 1478/// ParseUnaryExprOrTypeTraitExpression - Parse a sizeof or alignof expression. 1479/// unary-expression: [C99 6.5.3] 1480/// 'sizeof' unary-expression 1481/// 'sizeof' '(' type-name ')' 1482/// [C++0x] 'sizeof' '...' '(' identifier ')' 1483/// [GNU] '__alignof' unary-expression 1484/// [GNU] '__alignof' '(' type-name ')' 1485/// [C++0x] 'alignof' '(' type-id ')' 1486ExprResult Parser::ParseUnaryExprOrTypeTraitExpression() { 1487 assert((Tok.is(tok::kw_sizeof) || Tok.is(tok::kw___alignof) 1488 || Tok.is(tok::kw_alignof) || Tok.is(tok::kw_vec_step)) && 1489 "Not a sizeof/alignof/vec_step expression!"); 1490 Token OpTok = Tok; 1491 ConsumeToken(); 1492 1493 // [C++0x] 'sizeof' '...' '(' identifier ')' 1494 if (Tok.is(tok::ellipsis) && OpTok.is(tok::kw_sizeof)) { 1495 SourceLocation EllipsisLoc = ConsumeToken(); 1496 SourceLocation LParenLoc, RParenLoc; 1497 IdentifierInfo *Name = 0; 1498 SourceLocation NameLoc; 1499 if (Tok.is(tok::l_paren)) { 1500 BalancedDelimiterTracker T(*this, tok::l_paren); 1501 T.consumeOpen(); 1502 LParenLoc = T.getOpenLocation(); 1503 if (Tok.is(tok::identifier)) { 1504 Name = Tok.getIdentifierInfo(); 1505 NameLoc = ConsumeToken(); 1506 T.consumeClose(); 1507 RParenLoc = T.getCloseLocation(); 1508 if (RParenLoc.isInvalid()) 1509 RParenLoc = PP.getLocForEndOfToken(NameLoc); 1510 } else { 1511 Diag(Tok, diag::err_expected_parameter_pack); 1512 SkipUntil(tok::r_paren); 1513 } 1514 } else if (Tok.is(tok::identifier)) { 1515 Name = Tok.getIdentifierInfo(); 1516 NameLoc = ConsumeToken(); 1517 LParenLoc = PP.getLocForEndOfToken(EllipsisLoc); 1518 RParenLoc = PP.getLocForEndOfToken(NameLoc); 1519 Diag(LParenLoc, diag::err_paren_sizeof_parameter_pack) 1520 << Name 1521 << FixItHint::CreateInsertion(LParenLoc, "(") 1522 << FixItHint::CreateInsertion(RParenLoc, ")"); 1523 } else { 1524 Diag(Tok, diag::err_sizeof_parameter_pack); 1525 } 1526 1527 if (!Name) 1528 return ExprError(); 1529 1530 return Actions.ActOnSizeofParameterPackExpr(getCurScope(), 1531 OpTok.getLocation(), 1532 *Name, NameLoc, 1533 RParenLoc); 1534 } 1535 1536 bool isCastExpr; 1537 ParsedType CastTy; 1538 SourceRange CastRange; 1539 ExprResult Operand = ParseExprAfterUnaryExprOrTypeTrait(OpTok, 1540 isCastExpr, 1541 CastTy, 1542 CastRange); 1543 1544 UnaryExprOrTypeTrait ExprKind = UETT_SizeOf; 1545 if (OpTok.is(tok::kw_alignof) || OpTok.is(tok::kw___alignof)) 1546 ExprKind = UETT_AlignOf; 1547 else if (OpTok.is(tok::kw_vec_step)) 1548 ExprKind = UETT_VecStep; 1549 1550 if (isCastExpr) 1551 return Actions.ActOnUnaryExprOrTypeTraitExpr(OpTok.getLocation(), 1552 ExprKind, 1553 /*isType=*/true, 1554 CastTy.getAsOpaquePtr(), 1555 CastRange); 1556 1557 // If we get here, the operand to the sizeof/alignof was an expresion. 1558 if (!Operand.isInvalid()) 1559 Operand = Actions.ActOnUnaryExprOrTypeTraitExpr(OpTok.getLocation(), 1560 ExprKind, 1561 /*isType=*/false, 1562 Operand.release(), 1563 CastRange); 1564 return move(Operand); 1565} 1566 1567/// ParseBuiltinPrimaryExpression 1568/// 1569/// primary-expression: [C99 6.5.1] 1570/// [GNU] '__builtin_va_arg' '(' assignment-expression ',' type-name ')' 1571/// [GNU] '__builtin_offsetof' '(' type-name ',' offsetof-member-designator')' 1572/// [GNU] '__builtin_choose_expr' '(' assign-expr ',' assign-expr ',' 1573/// assign-expr ')' 1574/// [GNU] '__builtin_types_compatible_p' '(' type-name ',' type-name ')' 1575/// [OCL] '__builtin_astype' '(' type-name expr ')' 1576/// 1577/// [GNU] offsetof-member-designator: 1578/// [GNU] identifier 1579/// [GNU] offsetof-member-designator '.' identifier 1580/// [GNU] offsetof-member-designator '[' expression ']' 1581/// 1582ExprResult Parser::ParseBuiltinPrimaryExpression() { 1583 ExprResult Res; 1584 const IdentifierInfo *BuiltinII = Tok.getIdentifierInfo(); 1585 1586 tok::TokenKind T = Tok.getKind(); 1587 SourceLocation StartLoc = ConsumeToken(); // Eat the builtin identifier. 1588 1589 // All of these start with an open paren. 1590 if (Tok.isNot(tok::l_paren)) 1591 return ExprError(Diag(Tok, diag::err_expected_lparen_after_id) 1592 << BuiltinII); 1593 1594 BalancedDelimiterTracker PT(*this, tok::l_paren); 1595 PT.consumeOpen(); 1596 1597 // TODO: Build AST. 1598 1599 switch (T) { 1600 default: llvm_unreachable("Not a builtin primary expression!"); 1601 case tok::kw___builtin_va_arg: { 1602 ExprResult Expr(ParseAssignmentExpression()); 1603 1604 if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "",tok::r_paren)) 1605 Expr = ExprError(); 1606 1607 TypeResult Ty = ParseTypeName(); 1608 1609 if (Tok.isNot(tok::r_paren)) { 1610 Diag(Tok, diag::err_expected_rparen); 1611 Expr = ExprError(); 1612 } 1613 1614 if (Expr.isInvalid() || Ty.isInvalid()) 1615 Res = ExprError(); 1616 else 1617 Res = Actions.ActOnVAArg(StartLoc, Expr.take(), Ty.get(), ConsumeParen()); 1618 break; 1619 } 1620 case tok::kw___builtin_offsetof: { 1621 SourceLocation TypeLoc = Tok.getLocation(); 1622 TypeResult Ty = ParseTypeName(); 1623 if (Ty.isInvalid()) { 1624 SkipUntil(tok::r_paren); 1625 return ExprError(); 1626 } 1627 1628 if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "",tok::r_paren)) 1629 return ExprError(); 1630 1631 // We must have at least one identifier here. 1632 if (Tok.isNot(tok::identifier)) { 1633 Diag(Tok, diag::err_expected_ident); 1634 SkipUntil(tok::r_paren); 1635 return ExprError(); 1636 } 1637 1638 // Keep track of the various subcomponents we see. 1639 SmallVector<Sema::OffsetOfComponent, 4> Comps; 1640 1641 Comps.push_back(Sema::OffsetOfComponent()); 1642 Comps.back().isBrackets = false; 1643 Comps.back().U.IdentInfo = Tok.getIdentifierInfo(); 1644 Comps.back().LocStart = Comps.back().LocEnd = ConsumeToken(); 1645 1646 // FIXME: This loop leaks the index expressions on error. 1647 while (1) { 1648 if (Tok.is(tok::period)) { 1649 // offsetof-member-designator: offsetof-member-designator '.' identifier 1650 Comps.push_back(Sema::OffsetOfComponent()); 1651 Comps.back().isBrackets = false; 1652 Comps.back().LocStart = ConsumeToken(); 1653 1654 if (Tok.isNot(tok::identifier)) { 1655 Diag(Tok, diag::err_expected_ident); 1656 SkipUntil(tok::r_paren); 1657 return ExprError(); 1658 } 1659 Comps.back().U.IdentInfo = Tok.getIdentifierInfo(); 1660 Comps.back().LocEnd = ConsumeToken(); 1661 1662 } else if (Tok.is(tok::l_square)) { 1663 // offsetof-member-designator: offsetof-member-design '[' expression ']' 1664 Comps.push_back(Sema::OffsetOfComponent()); 1665 Comps.back().isBrackets = true; 1666 BalancedDelimiterTracker ST(*this, tok::l_square); 1667 ST.consumeOpen(); 1668 Comps.back().LocStart = ST.getOpenLocation(); 1669 Res = ParseExpression(); 1670 if (Res.isInvalid()) { 1671 SkipUntil(tok::r_paren); 1672 return move(Res); 1673 } 1674 Comps.back().U.E = Res.release(); 1675 1676 ST.consumeClose(); 1677 Comps.back().LocEnd = ST.getCloseLocation(); 1678 } else { 1679 if (Tok.isNot(tok::r_paren)) { 1680 PT.consumeClose(); 1681 Res = ExprError(); 1682 } else if (Ty.isInvalid()) { 1683 Res = ExprError(); 1684 } else { 1685 PT.consumeClose(); 1686 Res = Actions.ActOnBuiltinOffsetOf(getCurScope(), StartLoc, TypeLoc, 1687 Ty.get(), &Comps[0], Comps.size(), 1688 PT.getCloseLocation()); 1689 } 1690 break; 1691 } 1692 } 1693 break; 1694 } 1695 case tok::kw___builtin_choose_expr: { 1696 ExprResult Cond(ParseAssignmentExpression()); 1697 if (Cond.isInvalid()) { 1698 SkipUntil(tok::r_paren); 1699 return move(Cond); 1700 } 1701 if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "",tok::r_paren)) 1702 return ExprError(); 1703 1704 ExprResult Expr1(ParseAssignmentExpression()); 1705 if (Expr1.isInvalid()) { 1706 SkipUntil(tok::r_paren); 1707 return move(Expr1); 1708 } 1709 if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "",tok::r_paren)) 1710 return ExprError(); 1711 1712 ExprResult Expr2(ParseAssignmentExpression()); 1713 if (Expr2.isInvalid()) { 1714 SkipUntil(tok::r_paren); 1715 return move(Expr2); 1716 } 1717 if (Tok.isNot(tok::r_paren)) { 1718 Diag(Tok, diag::err_expected_rparen); 1719 return ExprError(); 1720 } 1721 Res = Actions.ActOnChooseExpr(StartLoc, Cond.take(), Expr1.take(), 1722 Expr2.take(), ConsumeParen()); 1723 break; 1724 } 1725 case tok::kw___builtin_astype: { 1726 // The first argument is an expression to be converted, followed by a comma. 1727 ExprResult Expr(ParseAssignmentExpression()); 1728 if (Expr.isInvalid()) { 1729 SkipUntil(tok::r_paren); 1730 return ExprError(); 1731 } 1732 1733 if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "", 1734 tok::r_paren)) 1735 return ExprError(); 1736 1737 // Second argument is the type to bitcast to. 1738 TypeResult DestTy = ParseTypeName(); 1739 if (DestTy.isInvalid()) 1740 return ExprError(); 1741 1742 // Attempt to consume the r-paren. 1743 if (Tok.isNot(tok::r_paren)) { 1744 Diag(Tok, diag::err_expected_rparen); 1745 SkipUntil(tok::r_paren); 1746 return ExprError(); 1747 } 1748 1749 Res = Actions.ActOnAsTypeExpr(Expr.take(), DestTy.get(), StartLoc, 1750 ConsumeParen()); 1751 break; 1752 } 1753 } 1754 1755 if (Res.isInvalid()) 1756 return ExprError(); 1757 1758 // These can be followed by postfix-expr pieces because they are 1759 // primary-expressions. 1760 return ParsePostfixExpressionSuffix(Res.take()); 1761} 1762 1763/// ParseParenExpression - This parses the unit that starts with a '(' token, 1764/// based on what is allowed by ExprType. The actual thing parsed is returned 1765/// in ExprType. If stopIfCastExpr is true, it will only return the parsed type, 1766/// not the parsed cast-expression. 1767/// 1768/// primary-expression: [C99 6.5.1] 1769/// '(' expression ')' 1770/// [GNU] '(' compound-statement ')' (if !ParenExprOnly) 1771/// postfix-expression: [C99 6.5.2] 1772/// '(' type-name ')' '{' initializer-list '}' 1773/// '(' type-name ')' '{' initializer-list ',' '}' 1774/// cast-expression: [C99 6.5.4] 1775/// '(' type-name ')' cast-expression 1776/// [ARC] bridged-cast-expression 1777/// 1778/// [ARC] bridged-cast-expression: 1779/// (__bridge type-name) cast-expression 1780/// (__bridge_transfer type-name) cast-expression 1781/// (__bridge_retained type-name) cast-expression 1782ExprResult 1783Parser::ParseParenExpression(ParenParseOption &ExprType, bool stopIfCastExpr, 1784 bool isTypeCast, ParsedType &CastTy, 1785 SourceLocation &RParenLoc) { 1786 assert(Tok.is(tok::l_paren) && "Not a paren expr!"); 1787 GreaterThanIsOperatorScope G(GreaterThanIsOperator, true); 1788 BalancedDelimiterTracker T(*this, tok::l_paren); 1789 if (T.consumeOpen()) 1790 return ExprError(); 1791 SourceLocation OpenLoc = T.getOpenLocation(); 1792 1793 ExprResult Result(true); 1794 bool isAmbiguousTypeId; 1795 CastTy = ParsedType(); 1796 1797 if (Tok.is(tok::code_completion)) { 1798 Actions.CodeCompleteOrdinaryName(getCurScope(), 1799 ExprType >= CompoundLiteral? Sema::PCC_ParenthesizedExpression 1800 : Sema::PCC_Expression); 1801 cutOffParsing(); 1802 return ExprError(); 1803 } 1804 1805 // None of these cases should fall through with an invalid Result 1806 // unless they've already reported an error. 1807 1808 if (ExprType >= CompoundStmt && Tok.is(tok::l_brace)) { 1809 Diag(Tok, diag::ext_gnu_statement_expr); 1810 ParsedAttributes attrs(AttrFactory); 1811 StmtResult Stmt(ParseCompoundStatement(attrs, true)); 1812 ExprType = CompoundStmt; 1813 1814 // If the substmt parsed correctly, build the AST node. 1815 if (!Stmt.isInvalid()) 1816 Result = Actions.ActOnStmtExpr(OpenLoc, Stmt.take(), Tok.getLocation()); 1817 } else if (ExprType >= CompoundLiteral && 1818 (Tok.is(tok::kw___bridge) || 1819 Tok.is(tok::kw___bridge_transfer) || 1820 Tok.is(tok::kw___bridge_retained) || 1821 Tok.is(tok::kw___bridge_retain))) { 1822 tok::TokenKind tokenKind = Tok.getKind(); 1823 SourceLocation BridgeKeywordLoc = ConsumeToken(); 1824 1825 // Parse an Objective-C ARC ownership cast expression. 1826 ObjCBridgeCastKind Kind; 1827 if (tokenKind == tok::kw___bridge) 1828 Kind = OBC_Bridge; 1829 else if (tokenKind == tok::kw___bridge_transfer) 1830 Kind = OBC_BridgeTransfer; 1831 else if (tokenKind == tok::kw___bridge_retained) 1832 Kind = OBC_BridgeRetained; 1833 else { 1834 // As a hopefully temporary workaround, allow __bridge_retain as 1835 // a synonym for __bridge_retained, but only in system headers. 1836 assert(tokenKind == tok::kw___bridge_retain); 1837 Kind = OBC_BridgeRetained; 1838 if (!PP.getSourceManager().isInSystemHeader(BridgeKeywordLoc)) 1839 Diag(BridgeKeywordLoc, diag::err_arc_bridge_retain) 1840 << FixItHint::CreateReplacement(BridgeKeywordLoc, 1841 "__bridge_retained"); 1842 } 1843 1844 TypeResult Ty = ParseTypeName(); 1845 T.consumeClose(); 1846 RParenLoc = T.getCloseLocation(); 1847 ExprResult SubExpr = ParseCastExpression(/*isUnaryExpression=*/false); 1848 1849 if (Ty.isInvalid() || SubExpr.isInvalid()) 1850 return ExprError(); 1851 1852 return Actions.ActOnObjCBridgedCast(getCurScope(), OpenLoc, Kind, 1853 BridgeKeywordLoc, Ty.get(), 1854 RParenLoc, SubExpr.get()); 1855 } else if (ExprType >= CompoundLiteral && 1856 isTypeIdInParens(isAmbiguousTypeId)) { 1857 1858 // Otherwise, this is a compound literal expression or cast expression. 1859 1860 // In C++, if the type-id is ambiguous we disambiguate based on context. 1861 // If stopIfCastExpr is true the context is a typeof/sizeof/alignof 1862 // in which case we should treat it as type-id. 1863 // if stopIfCastExpr is false, we need to determine the context past the 1864 // parens, so we defer to ParseCXXAmbiguousParenExpression for that. 1865 if (isAmbiguousTypeId && !stopIfCastExpr) { 1866 ExprResult res = ParseCXXAmbiguousParenExpression(ExprType, CastTy, T); 1867 RParenLoc = T.getCloseLocation(); 1868 return res; 1869 } 1870 1871 // Parse the type declarator. 1872 DeclSpec DS(AttrFactory); 1873 ParseSpecifierQualifierList(DS); 1874 Declarator DeclaratorInfo(DS, Declarator::TypeNameContext); 1875 ParseDeclarator(DeclaratorInfo); 1876 1877 // If our type is followed by an identifier and either ':' or ']', then 1878 // this is probably an Objective-C message send where the leading '[' is 1879 // missing. Recover as if that were the case. 1880 if (!DeclaratorInfo.isInvalidType() && Tok.is(tok::identifier) && 1881 !InMessageExpression && getLang().ObjC1 && 1882 (NextToken().is(tok::colon) || NextToken().is(tok::r_square))) { 1883 TypeResult Ty; 1884 { 1885 InMessageExpressionRAIIObject InMessage(*this, false); 1886 Ty = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo); 1887 } 1888 Result = ParseObjCMessageExpressionBody(SourceLocation(), 1889 SourceLocation(), 1890 Ty.get(), 0); 1891 } else { 1892 // Match the ')'. 1893 T.consumeClose(); 1894 RParenLoc = T.getCloseLocation(); 1895 if (Tok.is(tok::l_brace)) { 1896 ExprType = CompoundLiteral; 1897 TypeResult Ty; 1898 { 1899 InMessageExpressionRAIIObject InMessage(*this, false); 1900 Ty = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo); 1901 } 1902 return ParseCompoundLiteralExpression(Ty.get(), OpenLoc, RParenLoc); 1903 } 1904 1905 if (ExprType == CastExpr) { 1906 // We parsed '(' type-name ')' and the thing after it wasn't a '{'. 1907 1908 if (DeclaratorInfo.isInvalidType()) 1909 return ExprError(); 1910 1911 // Note that this doesn't parse the subsequent cast-expression, it just 1912 // returns the parsed type to the callee. 1913 if (stopIfCastExpr) { 1914 TypeResult Ty; 1915 { 1916 InMessageExpressionRAIIObject InMessage(*this, false); 1917 Ty = Actions.ActOnTypeName(getCurScope(), DeclaratorInfo); 1918 } 1919 CastTy = Ty.get(); 1920 return ExprResult(); 1921 } 1922 1923 // Reject the cast of super idiom in ObjC. 1924 if (Tok.is(tok::identifier) && getLang().ObjC1 && 1925 Tok.getIdentifierInfo() == Ident_super && 1926 getCurScope()->isInObjcMethodScope() && 1927 GetLookAheadToken(1).isNot(tok::period)) { 1928 Diag(Tok.getLocation(), diag::err_illegal_super_cast) 1929 << SourceRange(OpenLoc, RParenLoc); 1930 return ExprError(); 1931 } 1932 1933 // Parse the cast-expression that follows it next. 1934 // TODO: For cast expression with CastTy. 1935 Result = ParseCastExpression(/*isUnaryExpression=*/false, 1936 /*isAddressOfOperand=*/false, 1937 /*isTypeCast=*/true); 1938 if (!Result.isInvalid()) { 1939 Result = Actions.ActOnCastExpr(getCurScope(), OpenLoc, 1940 DeclaratorInfo, CastTy, 1941 RParenLoc, Result.take()); 1942 } 1943 return move(Result); 1944 } 1945 1946 Diag(Tok, diag::err_expected_lbrace_in_compound_literal); 1947 return ExprError(); 1948 } 1949 } else if (isTypeCast) { 1950 // Parse the expression-list. 1951 InMessageExpressionRAIIObject InMessage(*this, false); 1952 1953 ExprVector ArgExprs(Actions); 1954 CommaLocsTy CommaLocs; 1955 1956 if (!ParseExpressionList(ArgExprs, CommaLocs)) { 1957 ExprType = SimpleExpr; 1958 Result = Actions.ActOnParenOrParenListExpr(OpenLoc, Tok.getLocation(), 1959 move_arg(ArgExprs)); 1960 } 1961 } else { 1962 InMessageExpressionRAIIObject InMessage(*this, false); 1963 1964 Result = ParseExpression(); 1965 ExprType = SimpleExpr; 1966 1967 // Don't build a paren expression unless we actually match a ')'. 1968 if (!Result.isInvalid() && Tok.is(tok::r_paren)) 1969 Result = Actions.ActOnParenExpr(OpenLoc, Tok.getLocation(), Result.take()); 1970 } 1971 1972 // Match the ')'. 1973 if (Result.isInvalid()) { 1974 SkipUntil(tok::r_paren); 1975 return ExprError(); 1976 } 1977 1978 T.consumeClose(); 1979 RParenLoc = T.getCloseLocation(); 1980 return move(Result); 1981} 1982 1983/// ParseCompoundLiteralExpression - We have parsed the parenthesized type-name 1984/// and we are at the left brace. 1985/// 1986/// postfix-expression: [C99 6.5.2] 1987/// '(' type-name ')' '{' initializer-list '}' 1988/// '(' type-name ')' '{' initializer-list ',' '}' 1989/// 1990ExprResult 1991Parser::ParseCompoundLiteralExpression(ParsedType Ty, 1992 SourceLocation LParenLoc, 1993 SourceLocation RParenLoc) { 1994 assert(Tok.is(tok::l_brace) && "Not a compound literal!"); 1995 if (!getLang().C99) // Compound literals don't exist in C90. 1996 Diag(LParenLoc, diag::ext_c99_compound_literal); 1997 ExprResult Result = ParseInitializer(); 1998 if (!Result.isInvalid() && Ty) 1999 return Actions.ActOnCompoundLiteral(LParenLoc, Ty, RParenLoc, Result.take()); 2000 return move(Result); 2001} 2002 2003/// ParseStringLiteralExpression - This handles the various token types that 2004/// form string literals, and also handles string concatenation [C99 5.1.1.2, 2005/// translation phase #6]. 2006/// 2007/// primary-expression: [C99 6.5.1] 2008/// string-literal 2009ExprResult Parser::ParseStringLiteralExpression() { 2010 assert(isTokenStringLiteral() && "Not a string literal!"); 2011 2012 // String concat. Note that keywords like __func__ and __FUNCTION__ are not 2013 // considered to be strings for concatenation purposes. 2014 SmallVector<Token, 4> StringToks; 2015 2016 do { 2017 StringToks.push_back(Tok); 2018 ConsumeStringToken(); 2019 } while (isTokenStringLiteral()); 2020 2021 // Pass the set of string tokens, ready for concatenation, to the actions. 2022 return Actions.ActOnStringLiteral(&StringToks[0], StringToks.size()); 2023} 2024 2025/// ParseGenericSelectionExpression - Parse a C1X generic-selection 2026/// [C1X 6.5.1.1]. 2027/// 2028/// generic-selection: 2029/// _Generic ( assignment-expression , generic-assoc-list ) 2030/// generic-assoc-list: 2031/// generic-association 2032/// generic-assoc-list , generic-association 2033/// generic-association: 2034/// type-name : assignment-expression 2035/// default : assignment-expression 2036ExprResult Parser::ParseGenericSelectionExpression() { 2037 assert(Tok.is(tok::kw__Generic) && "_Generic keyword expected"); 2038 SourceLocation KeyLoc = ConsumeToken(); 2039 2040 if (!getLang().C1X) 2041 Diag(KeyLoc, diag::ext_c1x_generic_selection); 2042 2043 BalancedDelimiterTracker T(*this, tok::l_paren); 2044 if (T.expectAndConsume(diag::err_expected_lparen)) 2045 return ExprError(); 2046 2047 ExprResult ControllingExpr; 2048 { 2049 // C1X 6.5.1.1p3 "The controlling expression of a generic selection is 2050 // not evaluated." 2051 EnterExpressionEvaluationContext Unevaluated(Actions, Sema::Unevaluated); 2052 ControllingExpr = ParseAssignmentExpression(); 2053 if (ControllingExpr.isInvalid()) { 2054 SkipUntil(tok::r_paren); 2055 return ExprError(); 2056 } 2057 } 2058 2059 if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "")) { 2060 SkipUntil(tok::r_paren); 2061 return ExprError(); 2062 } 2063 2064 SourceLocation DefaultLoc; 2065 TypeVector Types(Actions); 2066 ExprVector Exprs(Actions); 2067 while (1) { 2068 ParsedType Ty; 2069 if (Tok.is(tok::kw_default)) { 2070 // C1X 6.5.1.1p2 "A generic selection shall have no more than one default 2071 // generic association." 2072 if (!DefaultLoc.isInvalid()) { 2073 Diag(Tok, diag::err_duplicate_default_assoc); 2074 Diag(DefaultLoc, diag::note_previous_default_assoc); 2075 SkipUntil(tok::r_paren); 2076 return ExprError(); 2077 } 2078 DefaultLoc = ConsumeToken(); 2079 Ty = ParsedType(); 2080 } else { 2081 ColonProtectionRAIIObject X(*this); 2082 TypeResult TR = ParseTypeName(); 2083 if (TR.isInvalid()) { 2084 SkipUntil(tok::r_paren); 2085 return ExprError(); 2086 } 2087 Ty = TR.release(); 2088 } 2089 Types.push_back(Ty); 2090 2091 if (ExpectAndConsume(tok::colon, diag::err_expected_colon, "")) { 2092 SkipUntil(tok::r_paren); 2093 return ExprError(); 2094 } 2095 2096 // FIXME: These expressions should be parsed in a potentially potentially 2097 // evaluated context. 2098 ExprResult ER(ParseAssignmentExpression()); 2099 if (ER.isInvalid()) { 2100 SkipUntil(tok::r_paren); 2101 return ExprError(); 2102 } 2103 Exprs.push_back(ER.release()); 2104 2105 if (Tok.isNot(tok::comma)) 2106 break; 2107 ConsumeToken(); 2108 } 2109 2110 T.consumeClose(); 2111 if (T.getCloseLocation().isInvalid()) 2112 return ExprError(); 2113 2114 return Actions.ActOnGenericSelectionExpr(KeyLoc, DefaultLoc, 2115 T.getCloseLocation(), 2116 ControllingExpr.release(), 2117 move_arg(Types), move_arg(Exprs)); 2118} 2119 2120/// ParseExpressionList - Used for C/C++ (argument-)expression-list. 2121/// 2122/// argument-expression-list: 2123/// assignment-expression 2124/// argument-expression-list , assignment-expression 2125/// 2126/// [C++] expression-list: 2127/// [C++] assignment-expression 2128/// [C++] expression-list , assignment-expression 2129/// 2130/// [C++0x] expression-list: 2131/// [C++0x] initializer-list 2132/// 2133/// [C++0x] initializer-list 2134/// [C++0x] initializer-clause ...[opt] 2135/// [C++0x] initializer-list , initializer-clause ...[opt] 2136/// 2137/// [C++0x] initializer-clause: 2138/// [C++0x] assignment-expression 2139/// [C++0x] braced-init-list 2140/// 2141bool Parser::ParseExpressionList(SmallVectorImpl<Expr*> &Exprs, 2142 SmallVectorImpl<SourceLocation> &CommaLocs, 2143 void (Sema::*Completer)(Scope *S, 2144 Expr *Data, 2145 Expr **Args, 2146 unsigned NumArgs), 2147 Expr *Data) { 2148 while (1) { 2149 if (Tok.is(tok::code_completion)) { 2150 if (Completer) 2151 (Actions.*Completer)(getCurScope(), Data, Exprs.data(), Exprs.size()); 2152 else 2153 Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Expression); 2154 cutOffParsing(); 2155 return true; 2156 } 2157 2158 ExprResult Expr; 2159 if (getLang().CPlusPlus0x && Tok.is(tok::l_brace)) 2160 Expr = ParseBraceInitializer(); 2161 else 2162 Expr = ParseAssignmentExpression(); 2163 2164 if (Tok.is(tok::ellipsis)) 2165 Expr = Actions.ActOnPackExpansion(Expr.get(), ConsumeToken()); 2166 if (Expr.isInvalid()) 2167 return true; 2168 2169 Exprs.push_back(Expr.release()); 2170 2171 if (Tok.isNot(tok::comma)) 2172 return false; 2173 // Move to the next argument, remember where the comma was. 2174 CommaLocs.push_back(ConsumeToken()); 2175 } 2176} 2177 2178/// ParseBlockId - Parse a block-id, which roughly looks like int (int x). 2179/// 2180/// [clang] block-id: 2181/// [clang] specifier-qualifier-list block-declarator 2182/// 2183void Parser::ParseBlockId() { 2184 if (Tok.is(tok::code_completion)) { 2185 Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Type); 2186 return cutOffParsing(); 2187 } 2188 2189 // Parse the specifier-qualifier-list piece. 2190 DeclSpec DS(AttrFactory); 2191 ParseSpecifierQualifierList(DS); 2192 2193 // Parse the block-declarator. 2194 Declarator DeclaratorInfo(DS, Declarator::BlockLiteralContext); 2195 ParseDeclarator(DeclaratorInfo); 2196 2197 // We do this for: ^ __attribute__((noreturn)) {, as DS has the attributes. 2198 DeclaratorInfo.takeAttributes(DS.getAttributes(), SourceLocation()); 2199 2200 MaybeParseGNUAttributes(DeclaratorInfo); 2201 2202 // Inform sema that we are starting a block. 2203 Actions.ActOnBlockArguments(DeclaratorInfo, getCurScope()); 2204} 2205 2206/// ParseBlockLiteralExpression - Parse a block literal, which roughly looks 2207/// like ^(int x){ return x+1; } 2208/// 2209/// block-literal: 2210/// [clang] '^' block-args[opt] compound-statement 2211/// [clang] '^' block-id compound-statement 2212/// [clang] block-args: 2213/// [clang] '(' parameter-list ')' 2214/// 2215ExprResult Parser::ParseBlockLiteralExpression() { 2216 assert(Tok.is(tok::caret) && "block literal starts with ^"); 2217 SourceLocation CaretLoc = ConsumeToken(); 2218 2219 PrettyStackTraceLoc CrashInfo(PP.getSourceManager(), CaretLoc, 2220 "block literal parsing"); 2221 2222 // Enter a scope to hold everything within the block. This includes the 2223 // argument decls, decls within the compound expression, etc. This also 2224 // allows determining whether a variable reference inside the block is 2225 // within or outside of the block. 2226 ParseScope BlockScope(this, Scope::BlockScope | Scope::FnScope | 2227 Scope::BreakScope | Scope::ContinueScope | 2228 Scope::DeclScope); 2229 2230 // Inform sema that we are starting a block. 2231 Actions.ActOnBlockStart(CaretLoc, getCurScope()); 2232 2233 // Parse the return type if present. 2234 DeclSpec DS(AttrFactory); 2235 Declarator ParamInfo(DS, Declarator::BlockLiteralContext); 2236 // FIXME: Since the return type isn't actually parsed, it can't be used to 2237 // fill ParamInfo with an initial valid range, so do it manually. 2238 ParamInfo.SetSourceRange(SourceRange(Tok.getLocation(), Tok.getLocation())); 2239 2240 // If this block has arguments, parse them. There is no ambiguity here with 2241 // the expression case, because the expression case requires a parameter list. 2242 if (Tok.is(tok::l_paren)) { 2243 ParseParenDeclarator(ParamInfo); 2244 // Parse the pieces after the identifier as if we had "int(...)". 2245 // SetIdentifier sets the source range end, but in this case we're past 2246 // that location. 2247 SourceLocation Tmp = ParamInfo.getSourceRange().getEnd(); 2248 ParamInfo.SetIdentifier(0, CaretLoc); 2249 ParamInfo.SetRangeEnd(Tmp); 2250 if (ParamInfo.isInvalidType()) { 2251 // If there was an error parsing the arguments, they may have 2252 // tried to use ^(x+y) which requires an argument list. Just 2253 // skip the whole block literal. 2254 Actions.ActOnBlockError(CaretLoc, getCurScope()); 2255 return ExprError(); 2256 } 2257 2258 MaybeParseGNUAttributes(ParamInfo); 2259 2260 // Inform sema that we are starting a block. 2261 Actions.ActOnBlockArguments(ParamInfo, getCurScope()); 2262 } else if (!Tok.is(tok::l_brace)) { 2263 ParseBlockId(); 2264 } else { 2265 // Otherwise, pretend we saw (void). 2266 ParsedAttributes attrs(AttrFactory); 2267 ParamInfo.AddTypeInfo(DeclaratorChunk::getFunction(true, false, 2268 SourceLocation(), 2269 0, 0, 0, 2270 true, SourceLocation(), 2271 SourceLocation(), 2272 EST_None, 2273 SourceLocation(), 2274 0, 0, 0, 0, 2275 CaretLoc, CaretLoc, 2276 ParamInfo), 2277 attrs, CaretLoc); 2278 2279 MaybeParseGNUAttributes(ParamInfo); 2280 2281 // Inform sema that we are starting a block. 2282 Actions.ActOnBlockArguments(ParamInfo, getCurScope()); 2283 } 2284 2285 2286 ExprResult Result(true); 2287 if (!Tok.is(tok::l_brace)) { 2288 // Saw something like: ^expr 2289 Diag(Tok, diag::err_expected_expression); 2290 Actions.ActOnBlockError(CaretLoc, getCurScope()); 2291 return ExprError(); 2292 } 2293 2294 StmtResult Stmt(ParseCompoundStatementBody()); 2295 BlockScope.Exit(); 2296 if (!Stmt.isInvalid()) 2297 Result = Actions.ActOnBlockStmtExpr(CaretLoc, Stmt.take(), getCurScope()); 2298 else 2299 Actions.ActOnBlockError(CaretLoc, getCurScope()); 2300 return move(Result); 2301} 2302