ParseExpr.cpp revision 208600
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/Parse/DeclSpec.h" 24#include "clang/Parse/Scope.h" 25#include "clang/Parse/Template.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. This returns: 34/// 35static prec::Level getBinOpPrecedence(tok::TokenKind Kind, 36 bool GreaterThanIsOperator, 37 bool CPlusPlus0x) { 38 switch (Kind) { 39 case tok::greater: 40 // C++ [temp.names]p3: 41 // [...] When parsing a template-argument-list, the first 42 // non-nested > is taken as the ending delimiter rather than a 43 // greater-than operator. [...] 44 if (GreaterThanIsOperator) 45 return prec::Relational; 46 return prec::Unknown; 47 48 case tok::greatergreater: 49 // C++0x [temp.names]p3: 50 // 51 // [...] Similarly, the first non-nested >> is treated as two 52 // consecutive but distinct > tokens, the first of which is 53 // taken as the end of the template-argument-list and completes 54 // the template-id. [...] 55 if (GreaterThanIsOperator || !CPlusPlus0x) 56 return prec::Shift; 57 return prec::Unknown; 58 59 default: return prec::Unknown; 60 case tok::comma: return prec::Comma; 61 case tok::equal: 62 case tok::starequal: 63 case tok::slashequal: 64 case tok::percentequal: 65 case tok::plusequal: 66 case tok::minusequal: 67 case tok::lesslessequal: 68 case tok::greatergreaterequal: 69 case tok::ampequal: 70 case tok::caretequal: 71 case tok::pipeequal: return prec::Assignment; 72 case tok::question: return prec::Conditional; 73 case tok::pipepipe: return prec::LogicalOr; 74 case tok::ampamp: return prec::LogicalAnd; 75 case tok::pipe: return prec::InclusiveOr; 76 case tok::caret: return prec::ExclusiveOr; 77 case tok::amp: return prec::And; 78 case tok::exclaimequal: 79 case tok::equalequal: return prec::Equality; 80 case tok::lessequal: 81 case tok::less: 82 case tok::greaterequal: return prec::Relational; 83 case tok::lessless: return prec::Shift; 84 case tok::plus: 85 case tok::minus: return prec::Additive; 86 case tok::percent: 87 case tok::slash: 88 case tok::star: return prec::Multiplicative; 89 case tok::periodstar: 90 case tok::arrowstar: return prec::PointerToMember; 91 } 92} 93 94 95/// ParseExpression - Simple precedence-based parser for binary/ternary 96/// operators. 97/// 98/// Note: we diverge from the C99 grammar when parsing the assignment-expression 99/// production. C99 specifies that the LHS of an assignment operator should be 100/// parsed as a unary-expression, but consistency dictates that it be a 101/// conditional-expession. In practice, the important thing here is that the 102/// LHS of an assignment has to be an l-value, which productions between 103/// unary-expression and conditional-expression don't produce. Because we want 104/// consistency, we parse the LHS as a conditional-expression, then check for 105/// l-value-ness in semantic analysis stages. 106/// 107/// pm-expression: [C++ 5.5] 108/// cast-expression 109/// pm-expression '.*' cast-expression 110/// pm-expression '->*' cast-expression 111/// 112/// multiplicative-expression: [C99 6.5.5] 113/// Note: in C++, apply pm-expression instead of cast-expression 114/// cast-expression 115/// multiplicative-expression '*' cast-expression 116/// multiplicative-expression '/' cast-expression 117/// multiplicative-expression '%' cast-expression 118/// 119/// additive-expression: [C99 6.5.6] 120/// multiplicative-expression 121/// additive-expression '+' multiplicative-expression 122/// additive-expression '-' multiplicative-expression 123/// 124/// shift-expression: [C99 6.5.7] 125/// additive-expression 126/// shift-expression '<<' additive-expression 127/// shift-expression '>>' additive-expression 128/// 129/// relational-expression: [C99 6.5.8] 130/// shift-expression 131/// relational-expression '<' shift-expression 132/// relational-expression '>' shift-expression 133/// relational-expression '<=' shift-expression 134/// relational-expression '>=' shift-expression 135/// 136/// equality-expression: [C99 6.5.9] 137/// relational-expression 138/// equality-expression '==' relational-expression 139/// equality-expression '!=' relational-expression 140/// 141/// AND-expression: [C99 6.5.10] 142/// equality-expression 143/// AND-expression '&' equality-expression 144/// 145/// exclusive-OR-expression: [C99 6.5.11] 146/// AND-expression 147/// exclusive-OR-expression '^' AND-expression 148/// 149/// inclusive-OR-expression: [C99 6.5.12] 150/// exclusive-OR-expression 151/// inclusive-OR-expression '|' exclusive-OR-expression 152/// 153/// logical-AND-expression: [C99 6.5.13] 154/// inclusive-OR-expression 155/// logical-AND-expression '&&' inclusive-OR-expression 156/// 157/// logical-OR-expression: [C99 6.5.14] 158/// logical-AND-expression 159/// logical-OR-expression '||' logical-AND-expression 160/// 161/// conditional-expression: [C99 6.5.15] 162/// logical-OR-expression 163/// logical-OR-expression '?' expression ':' conditional-expression 164/// [GNU] logical-OR-expression '?' ':' conditional-expression 165/// [C++] the third operand is an assignment-expression 166/// 167/// assignment-expression: [C99 6.5.16] 168/// conditional-expression 169/// unary-expression assignment-operator assignment-expression 170/// [C++] throw-expression [C++ 15] 171/// 172/// assignment-operator: one of 173/// = *= /= %= += -= <<= >>= &= ^= |= 174/// 175/// expression: [C99 6.5.17] 176/// assignment-expression 177/// expression ',' assignment-expression 178/// 179Parser::OwningExprResult Parser::ParseExpression() { 180 OwningExprResult LHS(ParseAssignmentExpression()); 181 if (LHS.isInvalid()) return move(LHS); 182 183 return ParseRHSOfBinaryExpression(move(LHS), prec::Comma); 184} 185 186/// This routine is called when the '@' is seen and consumed. 187/// Current token is an Identifier and is not a 'try'. This 188/// routine is necessary to disambiguate @try-statement from, 189/// for example, @encode-expression. 190/// 191Parser::OwningExprResult 192Parser::ParseExpressionWithLeadingAt(SourceLocation AtLoc) { 193 OwningExprResult LHS(ParseObjCAtExpression(AtLoc)); 194 if (LHS.isInvalid()) return move(LHS); 195 196 return ParseRHSOfBinaryExpression(move(LHS), prec::Comma); 197} 198 199/// This routine is called when a leading '__extension__' is seen and 200/// consumed. This is necessary because the token gets consumed in the 201/// process of disambiguating between an expression and a declaration. 202Parser::OwningExprResult 203Parser::ParseExpressionWithLeadingExtension(SourceLocation ExtLoc) { 204 OwningExprResult LHS(Actions, true); 205 { 206 // Silence extension warnings in the sub-expression 207 ExtensionRAIIObject O(Diags); 208 209 LHS = ParseCastExpression(false); 210 if (LHS.isInvalid()) return move(LHS); 211 } 212 213 LHS = Actions.ActOnUnaryOp(CurScope, ExtLoc, tok::kw___extension__, 214 move(LHS)); 215 if (LHS.isInvalid()) return move(LHS); 216 217 return ParseRHSOfBinaryExpression(move(LHS), prec::Comma); 218} 219 220/// ParseAssignmentExpression - Parse an expr that doesn't include commas. 221/// 222Parser::OwningExprResult Parser::ParseAssignmentExpression() { 223 if (Tok.is(tok::code_completion)) { 224 Actions.CodeCompleteOrdinaryName(CurScope, Action::CCC_Expression); 225 ConsumeCodeCompletionToken(); 226 } 227 228 if (Tok.is(tok::kw_throw)) 229 return ParseThrowExpression(); 230 231 OwningExprResult LHS(ParseCastExpression(false)); 232 if (LHS.isInvalid()) return move(LHS); 233 234 return ParseRHSOfBinaryExpression(move(LHS), prec::Assignment); 235} 236 237/// ParseAssignmentExprWithObjCMessageExprStart - Parse an assignment expression 238/// where part of an objc message send has already been parsed. In this case 239/// LBracLoc indicates the location of the '[' of the message send, and either 240/// ReceiverName or ReceiverExpr is non-null indicating the receiver of the 241/// message. 242/// 243/// Since this handles full assignment-expression's, it handles postfix 244/// expressions and other binary operators for these expressions as well. 245Parser::OwningExprResult 246Parser::ParseAssignmentExprWithObjCMessageExprStart(SourceLocation LBracLoc, 247 SourceLocation SuperLoc, 248 TypeTy *ReceiverType, 249 ExprArg ReceiverExpr) { 250 OwningExprResult R(ParseObjCMessageExpressionBody(LBracLoc, SuperLoc, 251 ReceiverType, 252 move(ReceiverExpr))); 253 if (R.isInvalid()) return move(R); 254 R = ParsePostfixExpressionSuffix(move(R)); 255 if (R.isInvalid()) return move(R); 256 return ParseRHSOfBinaryExpression(move(R), prec::Assignment); 257} 258 259 260Parser::OwningExprResult Parser::ParseConstantExpression() { 261 // C++ [basic.def.odr]p2: 262 // An expression is potentially evaluated unless it appears where an 263 // integral constant expression is required (see 5.19) [...]. 264 EnterExpressionEvaluationContext Unevaluated(Actions, 265 Action::Unevaluated); 266 267 OwningExprResult LHS(ParseCastExpression(false)); 268 if (LHS.isInvalid()) return move(LHS); 269 270 return ParseRHSOfBinaryExpression(move(LHS), prec::Conditional); 271} 272 273/// ParseRHSOfBinaryExpression - Parse a binary expression that starts with 274/// LHS and has a precedence of at least MinPrec. 275Parser::OwningExprResult 276Parser::ParseRHSOfBinaryExpression(OwningExprResult LHS, prec::Level MinPrec) { 277 prec::Level NextTokPrec = getBinOpPrecedence(Tok.getKind(), 278 GreaterThanIsOperator, 279 getLang().CPlusPlus0x); 280 SourceLocation ColonLoc; 281 282 while (1) { 283 // If this token has a lower precedence than we are allowed to parse (e.g. 284 // because we are called recursively, or because the token is not a binop), 285 // then we are done! 286 if (NextTokPrec < MinPrec) 287 return move(LHS); 288 289 // Consume the operator, saving the operator token for error reporting. 290 Token OpToken = Tok; 291 ConsumeToken(); 292 293 // Special case handling for the ternary operator. 294 OwningExprResult TernaryMiddle(Actions, true); 295 if (NextTokPrec == prec::Conditional) { 296 if (Tok.isNot(tok::colon)) { 297 // Don't parse FOO:BAR as if it were a typo for FOO::BAR. 298 ColonProtectionRAIIObject X(*this); 299 300 // Handle this production specially: 301 // logical-OR-expression '?' expression ':' conditional-expression 302 // In particular, the RHS of the '?' is 'expression', not 303 // 'logical-OR-expression' as we might expect. 304 TernaryMiddle = ParseExpression(); 305 if (TernaryMiddle.isInvalid()) 306 return move(TernaryMiddle); 307 } else { 308 // Special case handling of "X ? Y : Z" where Y is empty: 309 // logical-OR-expression '?' ':' conditional-expression [GNU] 310 TernaryMiddle = 0; 311 Diag(Tok, diag::ext_gnu_conditional_expr); 312 } 313 314 if (Tok.is(tok::colon)) { 315 // Eat the colon. 316 ColonLoc = ConsumeToken(); 317 } else { 318 // Otherwise, we're missing a ':'. Assume that this was a typo that the 319 // user forgot. If we're not in a macro instantion, we can suggest a 320 // fixit hint. If there were two spaces before the current token, 321 // suggest inserting the colon in between them, otherwise insert ": ". 322 SourceLocation FILoc = Tok.getLocation(); 323 const char *FIText = ": "; 324 if (FILoc.isFileID()) { 325 const SourceManager &SM = PP.getSourceManager(); 326 bool IsInvalid = false; 327 const char *SourcePtr = 328 SM.getCharacterData(FILoc.getFileLocWithOffset(-1), &IsInvalid); 329 if (!IsInvalid && *SourcePtr == ' ') { 330 SourcePtr = 331 SM.getCharacterData(FILoc.getFileLocWithOffset(-2), &IsInvalid); 332 if (!IsInvalid && *SourcePtr == ' ') { 333 FILoc = FILoc.getFileLocWithOffset(-1); 334 FIText = ":"; 335 } 336 } 337 } 338 339 Diag(Tok, diag::err_expected_colon) 340 << FixItHint::CreateInsertion(FILoc, FIText); 341 Diag(OpToken, diag::note_matching) << "?"; 342 ColonLoc = Tok.getLocation(); 343 } 344 } 345 346 // Parse another leaf here for the RHS of the operator. 347 // ParseCastExpression works here because all RHS expressions in C have it 348 // as a prefix, at least. However, in C++, an assignment-expression could 349 // be a throw-expression, which is not a valid cast-expression. 350 // Therefore we need some special-casing here. 351 // Also note that the third operand of the conditional operator is 352 // an assignment-expression in C++. 353 OwningExprResult RHS(Actions); 354 if (getLang().CPlusPlus && NextTokPrec <= prec::Conditional) 355 RHS = ParseAssignmentExpression(); 356 else 357 RHS = ParseCastExpression(false); 358 if (RHS.isInvalid()) 359 return move(RHS); 360 361 // Remember the precedence of this operator and get the precedence of the 362 // operator immediately to the right of the RHS. 363 prec::Level ThisPrec = NextTokPrec; 364 NextTokPrec = getBinOpPrecedence(Tok.getKind(), GreaterThanIsOperator, 365 getLang().CPlusPlus0x); 366 367 // Assignment and conditional expressions are right-associative. 368 bool isRightAssoc = ThisPrec == prec::Conditional || 369 ThisPrec == prec::Assignment; 370 371 // Get the precedence of the operator to the right of the RHS. If it binds 372 // more tightly with RHS than we do, evaluate it completely first. 373 if (ThisPrec < NextTokPrec || 374 (ThisPrec == NextTokPrec && isRightAssoc)) { 375 // If this is left-associative, only parse things on the RHS that bind 376 // more tightly than the current operator. If it is left-associative, it 377 // is okay, to bind exactly as tightly. For example, compile A=B=C=D as 378 // A=(B=(C=D)), where each paren is a level of recursion here. 379 // The function takes ownership of the RHS. 380 RHS = ParseRHSOfBinaryExpression(move(RHS), 381 static_cast<prec::Level>(ThisPrec + !isRightAssoc)); 382 if (RHS.isInvalid()) 383 return move(RHS); 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(CurScope, OpToken.getLocation(), 403 OpToken.getKind(), move(LHS), move(RHS)); 404 } else 405 LHS = Actions.ActOnConditionalOp(OpToken.getLocation(), ColonLoc, 406 move(LHS), move(TernaryMiddle), 407 move(RHS)); 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/// 417Parser::OwningExprResult Parser::ParseCastExpression(bool isUnaryExpression, 418 bool isAddressOfOperand, 419 TypeTy *TypeOfCast) { 420 bool NotCastExpr; 421 OwningExprResult Res = ParseCastExpression(isUnaryExpression, 422 isAddressOfOperand, 423 NotCastExpr, 424 TypeOfCast); 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/// [GNU] '__alignof' unary-expression 448/// [GNU] '__alignof' '(' type-name ')' 449/// [C++0x] 'alignof' '(' type-id ')' 450/// [GNU] '&&' identifier 451/// [C++] new-expression 452/// [C++] delete-expression 453/// 454/// unary-operator: one of 455/// '&' '*' '+' '-' '~' '!' 456/// [GNU] '__extension__' '__real' '__imag' 457/// 458/// primary-expression: [C99 6.5.1] 459/// [C99] identifier 460/// [C++] id-expression 461/// constant 462/// string-literal 463/// [C++] boolean-literal [C++ 2.13.5] 464/// [C++0x] 'nullptr' [C++0x 2.14.7] 465/// '(' expression ')' 466/// '__func__' [C99 6.4.2.2] 467/// [GNU] '__FUNCTION__' 468/// [GNU] '__PRETTY_FUNCTION__' 469/// [GNU] '(' compound-statement ')' 470/// [GNU] '__builtin_va_arg' '(' assignment-expression ',' type-name ')' 471/// [GNU] '__builtin_offsetof' '(' type-name ',' offsetof-member-designator')' 472/// [GNU] '__builtin_choose_expr' '(' assign-expr ',' assign-expr ',' 473/// assign-expr ')' 474/// [GNU] '__builtin_types_compatible_p' '(' type-name ',' type-name ')' 475/// [GNU] '__null' 476/// [OBJC] '[' objc-message-expr ']' 477/// [OBJC] '@selector' '(' objc-selector-arg ')' 478/// [OBJC] '@protocol' '(' identifier ')' 479/// [OBJC] '@encode' '(' type-name ')' 480/// [OBJC] objc-string-literal 481/// [C++] simple-type-specifier '(' expression-list[opt] ')' [C++ 5.2.3] 482/// [C++] typename-specifier '(' expression-list[opt] ')' [C++ 5.2.3] 483/// [C++] 'const_cast' '<' type-name '>' '(' expression ')' [C++ 5.2p1] 484/// [C++] 'dynamic_cast' '<' type-name '>' '(' expression ')' [C++ 5.2p1] 485/// [C++] 'reinterpret_cast' '<' type-name '>' '(' expression ')' [C++ 5.2p1] 486/// [C++] 'static_cast' '<' type-name '>' '(' expression ')' [C++ 5.2p1] 487/// [C++] 'typeid' '(' expression ')' [C++ 5.2p1] 488/// [C++] 'typeid' '(' type-id ')' [C++ 5.2p1] 489/// [C++] 'this' [C++ 9.3.2] 490/// [G++] unary-type-trait '(' type-id ')' 491/// [G++] binary-type-trait '(' type-id ',' type-id ')' [TODO] 492/// [clang] '^' block-literal 493/// 494/// constant: [C99 6.4.4] 495/// integer-constant 496/// floating-constant 497/// enumeration-constant -> identifier 498/// character-constant 499/// 500/// id-expression: [C++ 5.1] 501/// unqualified-id 502/// qualified-id 503/// 504/// unqualified-id: [C++ 5.1] 505/// identifier 506/// operator-function-id 507/// conversion-function-id 508/// '~' class-name 509/// template-id 510/// 511/// new-expression: [C++ 5.3.4] 512/// '::'[opt] 'new' new-placement[opt] new-type-id 513/// new-initializer[opt] 514/// '::'[opt] 'new' new-placement[opt] '(' type-id ')' 515/// new-initializer[opt] 516/// 517/// delete-expression: [C++ 5.3.5] 518/// '::'[opt] 'delete' cast-expression 519/// '::'[opt] 'delete' '[' ']' cast-expression 520/// 521/// [GNU] unary-type-trait: 522/// '__has_nothrow_assign' [TODO] 523/// '__has_nothrow_copy' [TODO] 524/// '__has_nothrow_constructor' [TODO] 525/// '__has_trivial_assign' [TODO] 526/// '__has_trivial_copy' [TODO] 527/// '__has_trivial_constructor' 528/// '__has_trivial_destructor' 529/// '__has_virtual_destructor' [TODO] 530/// '__is_abstract' [TODO] 531/// '__is_class' 532/// '__is_empty' [TODO] 533/// '__is_enum' 534/// '__is_pod' 535/// '__is_polymorphic' 536/// '__is_union' 537/// 538/// [GNU] binary-type-trait: 539/// '__is_base_of' [TODO] 540/// 541Parser::OwningExprResult Parser::ParseCastExpression(bool isUnaryExpression, 542 bool isAddressOfOperand, 543 bool &NotCastExpr, 544 TypeTy *TypeOfCast) { 545 OwningExprResult Res(Actions); 546 tok::TokenKind SavedKind = Tok.getKind(); 547 NotCastExpr = false; 548 549 // This handles all of cast-expression, unary-expression, postfix-expression, 550 // and primary-expression. We handle them together like this for efficiency 551 // and to simplify handling of an expression starting with a '(' token: which 552 // may be one of a parenthesized expression, cast-expression, compound literal 553 // expression, or statement expression. 554 // 555 // If the parsed tokens consist of a primary-expression, the cases below 556 // call ParsePostfixExpressionSuffix to handle the postfix expression 557 // suffixes. Cases that cannot be followed by postfix exprs should 558 // return without invoking ParsePostfixExpressionSuffix. 559 switch (SavedKind) { 560 case tok::l_paren: { 561 // If this expression is limited to being a unary-expression, the parent can 562 // not start a cast expression. 563 ParenParseOption ParenExprType = 564 isUnaryExpression ? CompoundLiteral : CastExpr; 565 TypeTy *CastTy; 566 SourceLocation LParenLoc = Tok.getLocation(); 567 SourceLocation RParenLoc; 568 569 { 570 // The inside of the parens don't need to be a colon protected scope. 571 ColonProtectionRAIIObject X(*this, false); 572 573 Res = ParseParenExpression(ParenExprType, false/*stopIfCastExr*/, 574 TypeOfCast, CastTy, RParenLoc); 575 if (Res.isInvalid()) return move(Res); 576 } 577 578 switch (ParenExprType) { 579 case SimpleExpr: break; // Nothing else to do. 580 case CompoundStmt: break; // Nothing else to do. 581 case CompoundLiteral: 582 // We parsed '(' type-name ')' '{' ... '}'. If any suffixes of 583 // postfix-expression exist, parse them now. 584 break; 585 case CastExpr: 586 // We have parsed the cast-expression and no postfix-expr pieces are 587 // following. 588 return move(Res); 589 } 590 591 // These can be followed by postfix-expr pieces. 592 return ParsePostfixExpressionSuffix(move(Res)); 593 } 594 595 // primary-expression 596 case tok::numeric_constant: 597 // constant: integer-constant 598 // constant: floating-constant 599 600 Res = Actions.ActOnNumericConstant(Tok); 601 ConsumeToken(); 602 603 // These can be followed by postfix-expr pieces. 604 return ParsePostfixExpressionSuffix(move(Res)); 605 606 case tok::kw_true: 607 case tok::kw_false: 608 return ParseCXXBoolLiteral(); 609 610 case tok::kw_nullptr: 611 return Actions.ActOnCXXNullPtrLiteral(ConsumeToken()); 612 613 case tok::identifier: { // primary-expression: identifier 614 // unqualified-id: identifier 615 // constant: enumeration-constant 616 // Turn a potentially qualified name into a annot_typename or 617 // annot_cxxscope if it would be valid. This handles things like x::y, etc. 618 if (getLang().CPlusPlus) { 619 // Avoid the unnecessary parse-time lookup in the common case 620 // where the syntax forbids a type. 621 const Token &Next = NextToken(); 622 if (Next.is(tok::coloncolon) || 623 (!ColonIsSacred && Next.is(tok::colon)) || 624 Next.is(tok::less) || 625 Next.is(tok::l_paren)) { 626 // If TryAnnotateTypeOrScopeToken annotates the token, tail recurse. 627 if (TryAnnotateTypeOrScopeToken()) 628 return ExprError(); 629 if (!Tok.is(tok::identifier)) 630 return ParseCastExpression(isUnaryExpression, isAddressOfOperand); 631 } 632 } 633 634 // Consume the identifier so that we can see if it is followed by a '(' or 635 // '.'. 636 IdentifierInfo &II = *Tok.getIdentifierInfo(); 637 SourceLocation ILoc = ConsumeToken(); 638 639 // Support 'Class.property' and 'super.property' notation. 640 if (getLang().ObjC1 && Tok.is(tok::period) && 641 (Actions.getTypeName(II, ILoc, CurScope) || 642 // Allow the base to be 'super' if in an objc-method. 643 (&II == Ident_super && CurScope->isInObjcMethodScope()))) { 644 SourceLocation DotLoc = ConsumeToken(); 645 646 if (Tok.isNot(tok::identifier)) { 647 Diag(Tok, diag::err_expected_property_name); 648 return ExprError(); 649 } 650 IdentifierInfo &PropertyName = *Tok.getIdentifierInfo(); 651 SourceLocation PropertyLoc = ConsumeToken(); 652 653 Res = Actions.ActOnClassPropertyRefExpr(II, PropertyName, 654 ILoc, PropertyLoc); 655 // These can be followed by postfix-expr pieces. 656 return ParsePostfixExpressionSuffix(move(Res)); 657 } 658 659 // Function designators are allowed to be undeclared (C99 6.5.1p2), so we 660 // need to know whether or not this identifier is a function designator or 661 // not. 662 UnqualifiedId Name; 663 CXXScopeSpec ScopeSpec; 664 Name.setIdentifier(&II, ILoc); 665 Res = Actions.ActOnIdExpression(CurScope, ScopeSpec, Name, 666 Tok.is(tok::l_paren), false); 667 // These can be followed by postfix-expr pieces. 668 return ParsePostfixExpressionSuffix(move(Res)); 669 } 670 case tok::char_constant: // constant: character-constant 671 Res = Actions.ActOnCharacterConstant(Tok); 672 ConsumeToken(); 673 // These can be followed by postfix-expr pieces. 674 return ParsePostfixExpressionSuffix(move(Res)); 675 case tok::kw___func__: // primary-expression: __func__ [C99 6.4.2.2] 676 case tok::kw___FUNCTION__: // primary-expression: __FUNCTION__ [GNU] 677 case tok::kw___PRETTY_FUNCTION__: // primary-expression: __P..Y_F..N__ [GNU] 678 Res = Actions.ActOnPredefinedExpr(Tok.getLocation(), SavedKind); 679 ConsumeToken(); 680 // These can be followed by postfix-expr pieces. 681 return ParsePostfixExpressionSuffix(move(Res)); 682 case tok::string_literal: // primary-expression: string-literal 683 case tok::wide_string_literal: 684 Res = ParseStringLiteralExpression(); 685 if (Res.isInvalid()) return move(Res); 686 // This can be followed by postfix-expr pieces (e.g. "foo"[1]). 687 return ParsePostfixExpressionSuffix(move(Res)); 688 case tok::kw___builtin_va_arg: 689 case tok::kw___builtin_offsetof: 690 case tok::kw___builtin_choose_expr: 691 case tok::kw___builtin_types_compatible_p: 692 return ParseBuiltinPrimaryExpression(); 693 case tok::kw___null: 694 return Actions.ActOnGNUNullExpr(ConsumeToken()); 695 break; 696 case tok::plusplus: // unary-expression: '++' unary-expression 697 case tok::minusminus: { // unary-expression: '--' unary-expression 698 SourceLocation SavedLoc = ConsumeToken(); 699 Res = ParseCastExpression(true); 700 if (!Res.isInvalid()) 701 Res = Actions.ActOnUnaryOp(CurScope, SavedLoc, SavedKind, move(Res)); 702 return move(Res); 703 } 704 case tok::amp: { // unary-expression: '&' cast-expression 705 // Special treatment because of member pointers 706 SourceLocation SavedLoc = ConsumeToken(); 707 Res = ParseCastExpression(false, true); 708 if (!Res.isInvalid()) 709 Res = Actions.ActOnUnaryOp(CurScope, SavedLoc, SavedKind, move(Res)); 710 return move(Res); 711 } 712 713 case tok::star: // unary-expression: '*' cast-expression 714 case tok::plus: // unary-expression: '+' cast-expression 715 case tok::minus: // unary-expression: '-' cast-expression 716 case tok::tilde: // unary-expression: '~' cast-expression 717 case tok::exclaim: // unary-expression: '!' cast-expression 718 case tok::kw___real: // unary-expression: '__real' cast-expression [GNU] 719 case tok::kw___imag: { // unary-expression: '__imag' cast-expression [GNU] 720 SourceLocation SavedLoc = ConsumeToken(); 721 Res = ParseCastExpression(false); 722 if (!Res.isInvalid()) 723 Res = Actions.ActOnUnaryOp(CurScope, SavedLoc, SavedKind, move(Res)); 724 return move(Res); 725 } 726 727 case tok::kw___extension__:{//unary-expression:'__extension__' cast-expr [GNU] 728 // __extension__ silences extension warnings in the subexpression. 729 ExtensionRAIIObject O(Diags); // Use RAII to do this. 730 SourceLocation SavedLoc = ConsumeToken(); 731 Res = ParseCastExpression(false); 732 if (!Res.isInvalid()) 733 Res = Actions.ActOnUnaryOp(CurScope, SavedLoc, SavedKind, move(Res)); 734 return move(Res); 735 } 736 case tok::kw_sizeof: // unary-expression: 'sizeof' unary-expression 737 // unary-expression: 'sizeof' '(' type-name ')' 738 case tok::kw_alignof: 739 case tok::kw___alignof: // unary-expression: '__alignof' unary-expression 740 // unary-expression: '__alignof' '(' type-name ')' 741 // unary-expression: 'alignof' '(' type-id ')' 742 return ParseSizeofAlignofExpression(); 743 case tok::ampamp: { // unary-expression: '&&' identifier 744 SourceLocation AmpAmpLoc = ConsumeToken(); 745 if (Tok.isNot(tok::identifier)) 746 return ExprError(Diag(Tok, diag::err_expected_ident)); 747 748 Diag(AmpAmpLoc, diag::ext_gnu_address_of_label); 749 Res = Actions.ActOnAddrLabel(AmpAmpLoc, Tok.getLocation(), 750 Tok.getIdentifierInfo()); 751 ConsumeToken(); 752 return move(Res); 753 } 754 case tok::kw_const_cast: 755 case tok::kw_dynamic_cast: 756 case tok::kw_reinterpret_cast: 757 case tok::kw_static_cast: 758 Res = ParseCXXCasts(); 759 // These can be followed by postfix-expr pieces. 760 return ParsePostfixExpressionSuffix(move(Res)); 761 case tok::kw_typeid: 762 Res = ParseCXXTypeid(); 763 // This can be followed by postfix-expr pieces. 764 return ParsePostfixExpressionSuffix(move(Res)); 765 case tok::kw_this: 766 Res = ParseCXXThis(); 767 // This can be followed by postfix-expr pieces. 768 return ParsePostfixExpressionSuffix(move(Res)); 769 770 case tok::kw_char: 771 case tok::kw_wchar_t: 772 case tok::kw_char16_t: 773 case tok::kw_char32_t: 774 case tok::kw_bool: 775 case tok::kw_short: 776 case tok::kw_int: 777 case tok::kw_long: 778 case tok::kw_signed: 779 case tok::kw_unsigned: 780 case tok::kw_float: 781 case tok::kw_double: 782 case tok::kw_void: 783 case tok::kw_typename: 784 case tok::kw_typeof: 785 case tok::kw___vector: 786 case tok::annot_typename: { 787 if (!getLang().CPlusPlus) { 788 Diag(Tok, diag::err_expected_expression); 789 return ExprError(); 790 } 791 792 if (SavedKind == tok::kw_typename) { 793 // postfix-expression: typename-specifier '(' expression-list[opt] ')' 794 if (TryAnnotateTypeOrScopeToken()) 795 return ExprError(); 796 } 797 798 // postfix-expression: simple-type-specifier '(' expression-list[opt] ')' 799 // 800 DeclSpec DS; 801 ParseCXXSimpleTypeSpecifier(DS); 802 if (Tok.isNot(tok::l_paren)) 803 return ExprError(Diag(Tok, diag::err_expected_lparen_after_type) 804 << DS.getSourceRange()); 805 806 Res = ParseCXXTypeConstructExpression(DS); 807 // This can be followed by postfix-expr pieces. 808 return ParsePostfixExpressionSuffix(move(Res)); 809 } 810 811 case tok::annot_cxxscope: { // [C++] id-expression: qualified-id 812 // If TryAnnotateTypeOrScopeToken annotates the token, tail recurse. 813 // (We can end up in this situation after tentative parsing.) 814 if (TryAnnotateTypeOrScopeToken()) 815 return ExprError(); 816 if (!Tok.is(tok::annot_cxxscope)) 817 return ParseCastExpression(isUnaryExpression, isAddressOfOperand, 818 NotCastExpr, TypeOfCast); 819 820 Token Next = NextToken(); 821 if (Next.is(tok::annot_template_id)) { 822 TemplateIdAnnotation *TemplateId 823 = static_cast<TemplateIdAnnotation *>(Next.getAnnotationValue()); 824 if (TemplateId->Kind == TNK_Type_template) { 825 // We have a qualified template-id that we know refers to a 826 // type, translate it into a type and continue parsing as a 827 // cast expression. 828 CXXScopeSpec SS; 829 ParseOptionalCXXScopeSpecifier(SS, /*ObjectType=*/0, false); 830 AnnotateTemplateIdTokenAsType(&SS); 831 return ParseCastExpression(isUnaryExpression, isAddressOfOperand, 832 NotCastExpr, TypeOfCast); 833 } 834 } 835 836 // Parse as an id-expression. 837 Res = ParseCXXIdExpression(isAddressOfOperand); 838 return ParsePostfixExpressionSuffix(move(Res)); 839 } 840 841 case tok::annot_template_id: { // [C++] template-id 842 TemplateIdAnnotation *TemplateId 843 = static_cast<TemplateIdAnnotation *>(Tok.getAnnotationValue()); 844 if (TemplateId->Kind == TNK_Type_template) { 845 // We have a template-id that we know refers to a type, 846 // translate it into a type and continue parsing as a cast 847 // expression. 848 AnnotateTemplateIdTokenAsType(); 849 return ParseCastExpression(isUnaryExpression, isAddressOfOperand, 850 NotCastExpr, TypeOfCast); 851 } 852 853 // Fall through to treat the template-id as an id-expression. 854 } 855 856 case tok::kw_operator: // [C++] id-expression: operator/conversion-function-id 857 Res = ParseCXXIdExpression(isAddressOfOperand); 858 return ParsePostfixExpressionSuffix(move(Res)); 859 860 case tok::coloncolon: { 861 // ::foo::bar -> global qualified name etc. If TryAnnotateTypeOrScopeToken 862 // annotates the token, tail recurse. 863 if (TryAnnotateTypeOrScopeToken()) 864 return ExprError(); 865 if (!Tok.is(tok::coloncolon)) 866 return ParseCastExpression(isUnaryExpression, isAddressOfOperand); 867 868 // ::new -> [C++] new-expression 869 // ::delete -> [C++] delete-expression 870 SourceLocation CCLoc = ConsumeToken(); 871 if (Tok.is(tok::kw_new)) 872 return ParseCXXNewExpression(true, CCLoc); 873 if (Tok.is(tok::kw_delete)) 874 return ParseCXXDeleteExpression(true, CCLoc); 875 876 // This is not a type name or scope specifier, it is an invalid expression. 877 Diag(CCLoc, diag::err_expected_expression); 878 return ExprError(); 879 } 880 881 case tok::kw_new: // [C++] new-expression 882 return ParseCXXNewExpression(false, Tok.getLocation()); 883 884 case tok::kw_delete: // [C++] delete-expression 885 return ParseCXXDeleteExpression(false, Tok.getLocation()); 886 887 case tok::kw___is_pod: // [GNU] unary-type-trait 888 case tok::kw___is_class: 889 case tok::kw___is_enum: 890 case tok::kw___is_union: 891 case tok::kw___is_empty: 892 case tok::kw___is_polymorphic: 893 case tok::kw___is_abstract: 894 case tok::kw___is_literal: 895 case tok::kw___has_trivial_constructor: 896 case tok::kw___has_trivial_copy: 897 case tok::kw___has_trivial_assign: 898 case tok::kw___has_trivial_destructor: 899 return ParseUnaryTypeTrait(); 900 901 case tok::at: { 902 SourceLocation AtLoc = ConsumeToken(); 903 return ParseObjCAtExpression(AtLoc); 904 } 905 case tok::caret: 906 return ParsePostfixExpressionSuffix(ParseBlockLiteralExpression()); 907 case tok::code_completion: 908 Actions.CodeCompleteOrdinaryName(CurScope, Action::CCC_Expression); 909 ConsumeCodeCompletionToken(); 910 return ParseCastExpression(isUnaryExpression, isAddressOfOperand, 911 NotCastExpr, TypeOfCast); 912 case tok::l_square: 913 // These can be followed by postfix-expr pieces. 914 if (getLang().ObjC1) 915 return ParsePostfixExpressionSuffix(ParseObjCMessageExpression()); 916 // FALL THROUGH. 917 default: 918 NotCastExpr = true; 919 return ExprError(); 920 } 921 922 // unreachable. 923 abort(); 924} 925 926/// ParsePostfixExpressionSuffix - Once the leading part of a postfix-expression 927/// is parsed, this method parses any suffixes that apply. 928/// 929/// postfix-expression: [C99 6.5.2] 930/// primary-expression 931/// postfix-expression '[' expression ']' 932/// postfix-expression '(' argument-expression-list[opt] ')' 933/// postfix-expression '.' identifier 934/// postfix-expression '->' identifier 935/// postfix-expression '++' 936/// postfix-expression '--' 937/// '(' type-name ')' '{' initializer-list '}' 938/// '(' type-name ')' '{' initializer-list ',' '}' 939/// 940/// argument-expression-list: [C99 6.5.2] 941/// argument-expression 942/// argument-expression-list ',' assignment-expression 943/// 944Parser::OwningExprResult 945Parser::ParsePostfixExpressionSuffix(OwningExprResult LHS) { 946 // Now that the primary-expression piece of the postfix-expression has been 947 // parsed, see if there are any postfix-expression pieces here. 948 SourceLocation Loc; 949 while (1) { 950 switch (Tok.getKind()) { 951 default: // Not a postfix-expression suffix. 952 return move(LHS); 953 case tok::l_square: { // postfix-expression: p-e '[' expression ']' 954 Loc = ConsumeBracket(); 955 OwningExprResult Idx(ParseExpression()); 956 957 SourceLocation RLoc = Tok.getLocation(); 958 959 if (!LHS.isInvalid() && !Idx.isInvalid() && Tok.is(tok::r_square)) { 960 LHS = Actions.ActOnArraySubscriptExpr(CurScope, move(LHS), Loc, 961 move(Idx), RLoc); 962 } else 963 LHS = ExprError(); 964 965 // Match the ']'. 966 MatchRHSPunctuation(tok::r_square, Loc); 967 break; 968 } 969 970 case tok::l_paren: { // p-e: p-e '(' argument-expression-list[opt] ')' 971 ExprVector ArgExprs(Actions); 972 CommaLocsTy CommaLocs; 973 974 Loc = ConsumeParen(); 975 976 if (Tok.is(tok::code_completion)) { 977 Actions.CodeCompleteCall(CurScope, LHS.get(), 0, 0); 978 ConsumeCodeCompletionToken(); 979 } 980 981 if (Tok.isNot(tok::r_paren)) { 982 if (ParseExpressionList(ArgExprs, CommaLocs, &Action::CodeCompleteCall, 983 LHS.get())) { 984 SkipUntil(tok::r_paren); 985 return ExprError(); 986 } 987 } 988 989 // Match the ')'. 990 if (Tok.isNot(tok::r_paren)) { 991 MatchRHSPunctuation(tok::r_paren, Loc); 992 return ExprError(); 993 } 994 995 if (!LHS.isInvalid()) { 996 assert((ArgExprs.size() == 0 || ArgExprs.size()-1 == CommaLocs.size())&& 997 "Unexpected number of commas!"); 998 LHS = Actions.ActOnCallExpr(CurScope, move(LHS), Loc, 999 move_arg(ArgExprs), CommaLocs.data(), 1000 Tok.getLocation()); 1001 } 1002 1003 ConsumeParen(); 1004 break; 1005 } 1006 case tok::arrow: 1007 case tok::period: { 1008 // postfix-expression: p-e '->' template[opt] id-expression 1009 // postfix-expression: p-e '.' template[opt] id-expression 1010 tok::TokenKind OpKind = Tok.getKind(); 1011 SourceLocation OpLoc = ConsumeToken(); // Eat the "." or "->" token. 1012 1013 CXXScopeSpec SS; 1014 Action::TypeTy *ObjectType = 0; 1015 bool MayBePseudoDestructor = false; 1016 if (getLang().CPlusPlus && !LHS.isInvalid()) { 1017 LHS = Actions.ActOnStartCXXMemberReference(CurScope, move(LHS), 1018 OpLoc, OpKind, ObjectType, 1019 MayBePseudoDestructor); 1020 if (LHS.isInvalid()) 1021 break; 1022 1023 ParseOptionalCXXScopeSpecifier(SS, ObjectType, false, 1024 &MayBePseudoDestructor); 1025 } 1026 1027 if (Tok.is(tok::code_completion)) { 1028 // Code completion for a member access expression. 1029 Actions.CodeCompleteMemberReferenceExpr(CurScope, LHS.get(), 1030 OpLoc, OpKind == tok::arrow); 1031 1032 ConsumeCodeCompletionToken(); 1033 } 1034 1035 if (MayBePseudoDestructor) { 1036 LHS = ParseCXXPseudoDestructor(move(LHS), OpLoc, OpKind, SS, 1037 ObjectType); 1038 break; 1039 } 1040 1041 // Either the action has told is that this cannot be a 1042 // pseudo-destructor expression (based on the type of base 1043 // expression), or we didn't see a '~' in the right place. We 1044 // can still parse a destructor name here, but in that case it 1045 // names a real destructor. 1046 UnqualifiedId Name; 1047 if (ParseUnqualifiedId(SS, 1048 /*EnteringContext=*/false, 1049 /*AllowDestructorName=*/true, 1050 /*AllowConstructorName=*/false, 1051 ObjectType, 1052 Name)) 1053 return ExprError(); 1054 1055 if (!LHS.isInvalid()) 1056 LHS = Actions.ActOnMemberAccessExpr(CurScope, move(LHS), OpLoc, 1057 OpKind, SS, Name, ObjCImpDecl, 1058 Tok.is(tok::l_paren)); 1059 break; 1060 } 1061 case tok::plusplus: // postfix-expression: postfix-expression '++' 1062 case tok::minusminus: // postfix-expression: postfix-expression '--' 1063 if (!LHS.isInvalid()) { 1064 LHS = Actions.ActOnPostfixUnaryOp(CurScope, Tok.getLocation(), 1065 Tok.getKind(), move(LHS)); 1066 } 1067 ConsumeToken(); 1068 break; 1069 } 1070 } 1071} 1072 1073/// ParseExprAfterTypeofSizeofAlignof - We parsed a typeof/sizeof/alignof and 1074/// we are at the start of an expression or a parenthesized type-id. 1075/// OpTok is the operand token (typeof/sizeof/alignof). Returns the expression 1076/// (isCastExpr == false) or the type (isCastExpr == true). 1077/// 1078/// unary-expression: [C99 6.5.3] 1079/// 'sizeof' unary-expression 1080/// 'sizeof' '(' type-name ')' 1081/// [GNU] '__alignof' unary-expression 1082/// [GNU] '__alignof' '(' type-name ')' 1083/// [C++0x] 'alignof' '(' type-id ')' 1084/// 1085/// [GNU] typeof-specifier: 1086/// typeof ( expressions ) 1087/// typeof ( type-name ) 1088/// [GNU/C++] typeof unary-expression 1089/// 1090Parser::OwningExprResult 1091Parser::ParseExprAfterTypeofSizeofAlignof(const Token &OpTok, 1092 bool &isCastExpr, 1093 TypeTy *&CastTy, 1094 SourceRange &CastRange) { 1095 1096 assert((OpTok.is(tok::kw_typeof) || OpTok.is(tok::kw_sizeof) || 1097 OpTok.is(tok::kw___alignof) || OpTok.is(tok::kw_alignof)) && 1098 "Not a typeof/sizeof/alignof expression!"); 1099 1100 OwningExprResult Operand(Actions); 1101 1102 // If the operand doesn't start with an '(', it must be an expression. 1103 if (Tok.isNot(tok::l_paren)) { 1104 isCastExpr = false; 1105 if (OpTok.is(tok::kw_typeof) && !getLang().CPlusPlus) { 1106 Diag(Tok,diag::err_expected_lparen_after_id) << OpTok.getIdentifierInfo(); 1107 return ExprError(); 1108 } 1109 1110 // C++0x [expr.sizeof]p1: 1111 // [...] The operand is either an expression, which is an unevaluated 1112 // operand (Clause 5) [...] 1113 // 1114 // The GNU typeof and alignof extensions also behave as unevaluated 1115 // operands. 1116 EnterExpressionEvaluationContext Unevaluated(Actions, 1117 Action::Unevaluated); 1118 Operand = ParseCastExpression(true/*isUnaryExpression*/); 1119 } else { 1120 // If it starts with a '(', we know that it is either a parenthesized 1121 // type-name, or it is a unary-expression that starts with a compound 1122 // literal, or starts with a primary-expression that is a parenthesized 1123 // expression. 1124 ParenParseOption ExprType = CastExpr; 1125 SourceLocation LParenLoc = Tok.getLocation(), RParenLoc; 1126 1127 // C++0x [expr.sizeof]p1: 1128 // [...] The operand is either an expression, which is an unevaluated 1129 // operand (Clause 5) [...] 1130 // 1131 // The GNU typeof and alignof extensions also behave as unevaluated 1132 // operands. 1133 EnterExpressionEvaluationContext Unevaluated(Actions, 1134 Action::Unevaluated); 1135 Operand = ParseParenExpression(ExprType, true/*stopIfCastExpr*/, 1136 0/*TypeOfCast*/, 1137 CastTy, RParenLoc); 1138 CastRange = SourceRange(LParenLoc, RParenLoc); 1139 1140 // If ParseParenExpression parsed a '(typename)' sequence only, then this is 1141 // a type. 1142 if (ExprType == CastExpr) { 1143 isCastExpr = true; 1144 return ExprEmpty(); 1145 } 1146 1147 // If this is a parenthesized expression, it is the start of a 1148 // unary-expression, but doesn't include any postfix pieces. Parse these 1149 // now if present. 1150 Operand = ParsePostfixExpressionSuffix(move(Operand)); 1151 } 1152 1153 // If we get here, the operand to the typeof/sizeof/alignof was an expresion. 1154 isCastExpr = false; 1155 return move(Operand); 1156} 1157 1158 1159/// ParseSizeofAlignofExpression - Parse a sizeof or alignof expression. 1160/// unary-expression: [C99 6.5.3] 1161/// 'sizeof' unary-expression 1162/// 'sizeof' '(' type-name ')' 1163/// [GNU] '__alignof' unary-expression 1164/// [GNU] '__alignof' '(' type-name ')' 1165/// [C++0x] 'alignof' '(' type-id ')' 1166Parser::OwningExprResult Parser::ParseSizeofAlignofExpression() { 1167 assert((Tok.is(tok::kw_sizeof) || Tok.is(tok::kw___alignof) 1168 || Tok.is(tok::kw_alignof)) && 1169 "Not a sizeof/alignof expression!"); 1170 Token OpTok = Tok; 1171 ConsumeToken(); 1172 1173 bool isCastExpr; 1174 TypeTy *CastTy; 1175 SourceRange CastRange; 1176 OwningExprResult Operand = ParseExprAfterTypeofSizeofAlignof(OpTok, 1177 isCastExpr, 1178 CastTy, 1179 CastRange); 1180 1181 if (isCastExpr) 1182 return Actions.ActOnSizeOfAlignOfExpr(OpTok.getLocation(), 1183 OpTok.is(tok::kw_sizeof), 1184 /*isType=*/true, CastTy, 1185 CastRange); 1186 1187 // If we get here, the operand to the sizeof/alignof was an expresion. 1188 if (!Operand.isInvalid()) 1189 Operand = Actions.ActOnSizeOfAlignOfExpr(OpTok.getLocation(), 1190 OpTok.is(tok::kw_sizeof), 1191 /*isType=*/false, 1192 Operand.release(), CastRange); 1193 return move(Operand); 1194} 1195 1196/// ParseBuiltinPrimaryExpression 1197/// 1198/// primary-expression: [C99 6.5.1] 1199/// [GNU] '__builtin_va_arg' '(' assignment-expression ',' type-name ')' 1200/// [GNU] '__builtin_offsetof' '(' type-name ',' offsetof-member-designator')' 1201/// [GNU] '__builtin_choose_expr' '(' assign-expr ',' assign-expr ',' 1202/// assign-expr ')' 1203/// [GNU] '__builtin_types_compatible_p' '(' type-name ',' type-name ')' 1204/// 1205/// [GNU] offsetof-member-designator: 1206/// [GNU] identifier 1207/// [GNU] offsetof-member-designator '.' identifier 1208/// [GNU] offsetof-member-designator '[' expression ']' 1209/// 1210Parser::OwningExprResult Parser::ParseBuiltinPrimaryExpression() { 1211 OwningExprResult Res(Actions); 1212 const IdentifierInfo *BuiltinII = Tok.getIdentifierInfo(); 1213 1214 tok::TokenKind T = Tok.getKind(); 1215 SourceLocation StartLoc = ConsumeToken(); // Eat the builtin identifier. 1216 1217 // All of these start with an open paren. 1218 if (Tok.isNot(tok::l_paren)) 1219 return ExprError(Diag(Tok, diag::err_expected_lparen_after_id) 1220 << BuiltinII); 1221 1222 SourceLocation LParenLoc = ConsumeParen(); 1223 // TODO: Build AST. 1224 1225 switch (T) { 1226 default: assert(0 && "Not a builtin primary expression!"); 1227 case tok::kw___builtin_va_arg: { 1228 OwningExprResult Expr(ParseAssignmentExpression()); 1229 if (Expr.isInvalid()) { 1230 SkipUntil(tok::r_paren); 1231 return ExprError(); 1232 } 1233 1234 if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "",tok::r_paren)) 1235 return ExprError(); 1236 1237 TypeResult Ty = ParseTypeName(); 1238 1239 if (Tok.isNot(tok::r_paren)) { 1240 Diag(Tok, diag::err_expected_rparen); 1241 return ExprError(); 1242 } 1243 if (Ty.isInvalid()) 1244 Res = ExprError(); 1245 else 1246 Res = Actions.ActOnVAArg(StartLoc, move(Expr), Ty.get(), ConsumeParen()); 1247 break; 1248 } 1249 case tok::kw___builtin_offsetof: { 1250 SourceLocation TypeLoc = Tok.getLocation(); 1251 TypeResult Ty = ParseTypeName(); 1252 if (Ty.isInvalid()) { 1253 SkipUntil(tok::r_paren); 1254 return ExprError(); 1255 } 1256 1257 if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "",tok::r_paren)) 1258 return ExprError(); 1259 1260 // We must have at least one identifier here. 1261 if (Tok.isNot(tok::identifier)) { 1262 Diag(Tok, diag::err_expected_ident); 1263 SkipUntil(tok::r_paren); 1264 return ExprError(); 1265 } 1266 1267 // Keep track of the various subcomponents we see. 1268 llvm::SmallVector<Action::OffsetOfComponent, 4> Comps; 1269 1270 Comps.push_back(Action::OffsetOfComponent()); 1271 Comps.back().isBrackets = false; 1272 Comps.back().U.IdentInfo = Tok.getIdentifierInfo(); 1273 Comps.back().LocStart = Comps.back().LocEnd = ConsumeToken(); 1274 1275 // FIXME: This loop leaks the index expressions on error. 1276 while (1) { 1277 if (Tok.is(tok::period)) { 1278 // offsetof-member-designator: offsetof-member-designator '.' identifier 1279 Comps.push_back(Action::OffsetOfComponent()); 1280 Comps.back().isBrackets = false; 1281 Comps.back().LocStart = ConsumeToken(); 1282 1283 if (Tok.isNot(tok::identifier)) { 1284 Diag(Tok, diag::err_expected_ident); 1285 SkipUntil(tok::r_paren); 1286 return ExprError(); 1287 } 1288 Comps.back().U.IdentInfo = Tok.getIdentifierInfo(); 1289 Comps.back().LocEnd = ConsumeToken(); 1290 1291 } else if (Tok.is(tok::l_square)) { 1292 // offsetof-member-designator: offsetof-member-design '[' expression ']' 1293 Comps.push_back(Action::OffsetOfComponent()); 1294 Comps.back().isBrackets = true; 1295 Comps.back().LocStart = ConsumeBracket(); 1296 Res = ParseExpression(); 1297 if (Res.isInvalid()) { 1298 SkipUntil(tok::r_paren); 1299 return move(Res); 1300 } 1301 Comps.back().U.E = Res.release(); 1302 1303 Comps.back().LocEnd = 1304 MatchRHSPunctuation(tok::r_square, Comps.back().LocStart); 1305 } else { 1306 if (Tok.isNot(tok::r_paren)) { 1307 MatchRHSPunctuation(tok::r_paren, LParenLoc); 1308 Res = ExprError(); 1309 } else if (Ty.isInvalid()) { 1310 Res = ExprError(); 1311 } else { 1312 Res = Actions.ActOnBuiltinOffsetOf(CurScope, StartLoc, TypeLoc, 1313 Ty.get(), &Comps[0], 1314 Comps.size(), ConsumeParen()); 1315 } 1316 break; 1317 } 1318 } 1319 break; 1320 } 1321 case tok::kw___builtin_choose_expr: { 1322 OwningExprResult Cond(ParseAssignmentExpression()); 1323 if (Cond.isInvalid()) { 1324 SkipUntil(tok::r_paren); 1325 return move(Cond); 1326 } 1327 if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "",tok::r_paren)) 1328 return ExprError(); 1329 1330 OwningExprResult Expr1(ParseAssignmentExpression()); 1331 if (Expr1.isInvalid()) { 1332 SkipUntil(tok::r_paren); 1333 return move(Expr1); 1334 } 1335 if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "",tok::r_paren)) 1336 return ExprError(); 1337 1338 OwningExprResult Expr2(ParseAssignmentExpression()); 1339 if (Expr2.isInvalid()) { 1340 SkipUntil(tok::r_paren); 1341 return move(Expr2); 1342 } 1343 if (Tok.isNot(tok::r_paren)) { 1344 Diag(Tok, diag::err_expected_rparen); 1345 return ExprError(); 1346 } 1347 Res = Actions.ActOnChooseExpr(StartLoc, move(Cond), move(Expr1), 1348 move(Expr2), ConsumeParen()); 1349 break; 1350 } 1351 case tok::kw___builtin_types_compatible_p: 1352 TypeResult Ty1 = ParseTypeName(); 1353 1354 if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "",tok::r_paren)) 1355 return ExprError(); 1356 1357 TypeResult Ty2 = ParseTypeName(); 1358 1359 if (Tok.isNot(tok::r_paren)) { 1360 Diag(Tok, diag::err_expected_rparen); 1361 return ExprError(); 1362 } 1363 1364 if (Ty1.isInvalid() || Ty2.isInvalid()) 1365 Res = ExprError(); 1366 else 1367 Res = Actions.ActOnTypesCompatibleExpr(StartLoc, Ty1.get(), Ty2.get(), 1368 ConsumeParen()); 1369 break; 1370 } 1371 1372 // These can be followed by postfix-expr pieces because they are 1373 // primary-expressions. 1374 return ParsePostfixExpressionSuffix(move(Res)); 1375} 1376 1377/// ParseParenExpression - This parses the unit that starts with a '(' token, 1378/// based on what is allowed by ExprType. The actual thing parsed is returned 1379/// in ExprType. If stopIfCastExpr is true, it will only return the parsed type, 1380/// not the parsed cast-expression. 1381/// 1382/// primary-expression: [C99 6.5.1] 1383/// '(' expression ')' 1384/// [GNU] '(' compound-statement ')' (if !ParenExprOnly) 1385/// postfix-expression: [C99 6.5.2] 1386/// '(' type-name ')' '{' initializer-list '}' 1387/// '(' type-name ')' '{' initializer-list ',' '}' 1388/// cast-expression: [C99 6.5.4] 1389/// '(' type-name ')' cast-expression 1390/// 1391Parser::OwningExprResult 1392Parser::ParseParenExpression(ParenParseOption &ExprType, bool stopIfCastExpr, 1393 TypeTy *TypeOfCast, TypeTy *&CastTy, 1394 SourceLocation &RParenLoc) { 1395 assert(Tok.is(tok::l_paren) && "Not a paren expr!"); 1396 GreaterThanIsOperatorScope G(GreaterThanIsOperator, true); 1397 SourceLocation OpenLoc = ConsumeParen(); 1398 OwningExprResult Result(Actions, true); 1399 bool isAmbiguousTypeId; 1400 CastTy = 0; 1401 1402 if (ExprType >= CompoundStmt && Tok.is(tok::l_brace)) { 1403 Diag(Tok, diag::ext_gnu_statement_expr); 1404 OwningStmtResult Stmt(ParseCompoundStatement(0, true)); 1405 ExprType = CompoundStmt; 1406 1407 // If the substmt parsed correctly, build the AST node. 1408 if (!Stmt.isInvalid() && Tok.is(tok::r_paren)) 1409 Result = Actions.ActOnStmtExpr(OpenLoc, move(Stmt), Tok.getLocation()); 1410 1411 } else if (ExprType >= CompoundLiteral && 1412 isTypeIdInParens(isAmbiguousTypeId)) { 1413 1414 // Otherwise, this is a compound literal expression or cast expression. 1415 1416 // In C++, if the type-id is ambiguous we disambiguate based on context. 1417 // If stopIfCastExpr is true the context is a typeof/sizeof/alignof 1418 // in which case we should treat it as type-id. 1419 // if stopIfCastExpr is false, we need to determine the context past the 1420 // parens, so we defer to ParseCXXAmbiguousParenExpression for that. 1421 if (isAmbiguousTypeId && !stopIfCastExpr) 1422 return ParseCXXAmbiguousParenExpression(ExprType, CastTy, 1423 OpenLoc, RParenLoc); 1424 1425 TypeResult Ty = ParseTypeName(); 1426 1427 // Match the ')'. 1428 if (Tok.is(tok::r_paren)) 1429 RParenLoc = ConsumeParen(); 1430 else 1431 MatchRHSPunctuation(tok::r_paren, OpenLoc); 1432 1433 if (Tok.is(tok::l_brace)) { 1434 ExprType = CompoundLiteral; 1435 return ParseCompoundLiteralExpression(Ty.get(), OpenLoc, RParenLoc); 1436 } 1437 1438 if (ExprType == CastExpr) { 1439 // We parsed '(' type-name ')' and the thing after it wasn't a '{'. 1440 1441 if (Ty.isInvalid()) 1442 return ExprError(); 1443 1444 CastTy = Ty.get(); 1445 1446 // Note that this doesn't parse the subsequent cast-expression, it just 1447 // returns the parsed type to the callee. 1448 if (stopIfCastExpr) 1449 return OwningExprResult(Actions); 1450 1451 // Reject the cast of super idiom in ObjC. 1452 if (Tok.is(tok::identifier) && getLang().ObjC1 && 1453 Tok.getIdentifierInfo() == Ident_super && 1454 CurScope->isInObjcMethodScope() && 1455 GetLookAheadToken(1).isNot(tok::period)) { 1456 Diag(Tok.getLocation(), diag::err_illegal_super_cast) 1457 << SourceRange(OpenLoc, RParenLoc); 1458 return ExprError(); 1459 } 1460 1461 // Parse the cast-expression that follows it next. 1462 // TODO: For cast expression with CastTy. 1463 Result = ParseCastExpression(false, false, CastTy); 1464 if (!Result.isInvalid()) 1465 Result = Actions.ActOnCastExpr(CurScope, OpenLoc, CastTy, RParenLoc, 1466 move(Result)); 1467 return move(Result); 1468 } 1469 1470 Diag(Tok, diag::err_expected_lbrace_in_compound_literal); 1471 return ExprError(); 1472 } else if (TypeOfCast) { 1473 // Parse the expression-list. 1474 ExprVector ArgExprs(Actions); 1475 CommaLocsTy CommaLocs; 1476 1477 if (!ParseExpressionList(ArgExprs, CommaLocs)) { 1478 ExprType = SimpleExpr; 1479 Result = Actions.ActOnParenOrParenListExpr(OpenLoc, Tok.getLocation(), 1480 move_arg(ArgExprs), TypeOfCast); 1481 } 1482 } else { 1483 Result = ParseExpression(); 1484 ExprType = SimpleExpr; 1485 if (!Result.isInvalid() && Tok.is(tok::r_paren)) 1486 Result = Actions.ActOnParenExpr(OpenLoc, Tok.getLocation(), move(Result)); 1487 } 1488 1489 // Match the ')'. 1490 if (Result.isInvalid()) { 1491 SkipUntil(tok::r_paren); 1492 return ExprError(); 1493 } 1494 1495 if (Tok.is(tok::r_paren)) 1496 RParenLoc = ConsumeParen(); 1497 else 1498 MatchRHSPunctuation(tok::r_paren, OpenLoc); 1499 1500 return move(Result); 1501} 1502 1503/// ParseCompoundLiteralExpression - We have parsed the parenthesized type-name 1504/// and we are at the left brace. 1505/// 1506/// postfix-expression: [C99 6.5.2] 1507/// '(' type-name ')' '{' initializer-list '}' 1508/// '(' type-name ')' '{' initializer-list ',' '}' 1509/// 1510Parser::OwningExprResult 1511Parser::ParseCompoundLiteralExpression(TypeTy *Ty, 1512 SourceLocation LParenLoc, 1513 SourceLocation RParenLoc) { 1514 assert(Tok.is(tok::l_brace) && "Not a compound literal!"); 1515 if (!getLang().C99) // Compound literals don't exist in C90. 1516 Diag(LParenLoc, diag::ext_c99_compound_literal); 1517 OwningExprResult Result = ParseInitializer(); 1518 if (!Result.isInvalid() && Ty) 1519 return Actions.ActOnCompoundLiteral(LParenLoc, Ty, RParenLoc, move(Result)); 1520 return move(Result); 1521} 1522 1523/// ParseStringLiteralExpression - This handles the various token types that 1524/// form string literals, and also handles string concatenation [C99 5.1.1.2, 1525/// translation phase #6]. 1526/// 1527/// primary-expression: [C99 6.5.1] 1528/// string-literal 1529Parser::OwningExprResult Parser::ParseStringLiteralExpression() { 1530 assert(isTokenStringLiteral() && "Not a string literal!"); 1531 1532 // String concat. Note that keywords like __func__ and __FUNCTION__ are not 1533 // considered to be strings for concatenation purposes. 1534 llvm::SmallVector<Token, 4> StringToks; 1535 1536 do { 1537 StringToks.push_back(Tok); 1538 ConsumeStringToken(); 1539 } while (isTokenStringLiteral()); 1540 1541 // Pass the set of string tokens, ready for concatenation, to the actions. 1542 return Actions.ActOnStringLiteral(&StringToks[0], StringToks.size()); 1543} 1544 1545/// ParseExpressionList - Used for C/C++ (argument-)expression-list. 1546/// 1547/// argument-expression-list: 1548/// assignment-expression 1549/// argument-expression-list , assignment-expression 1550/// 1551/// [C++] expression-list: 1552/// [C++] assignment-expression 1553/// [C++] expression-list , assignment-expression 1554/// 1555bool Parser::ParseExpressionList(ExprListTy &Exprs, CommaLocsTy &CommaLocs, 1556 void (Action::*Completer)(Scope *S, 1557 void *Data, 1558 ExprTy **Args, 1559 unsigned NumArgs), 1560 void *Data) { 1561 while (1) { 1562 if (Tok.is(tok::code_completion)) { 1563 if (Completer) 1564 (Actions.*Completer)(CurScope, Data, Exprs.data(), Exprs.size()); 1565 ConsumeCodeCompletionToken(); 1566 } 1567 1568 OwningExprResult Expr(ParseAssignmentExpression()); 1569 if (Expr.isInvalid()) 1570 return true; 1571 1572 Exprs.push_back(Expr.release()); 1573 1574 if (Tok.isNot(tok::comma)) 1575 return false; 1576 // Move to the next argument, remember where the comma was. 1577 CommaLocs.push_back(ConsumeToken()); 1578 } 1579} 1580 1581/// ParseBlockId - Parse a block-id, which roughly looks like int (int x). 1582/// 1583/// [clang] block-id: 1584/// [clang] specifier-qualifier-list block-declarator 1585/// 1586void Parser::ParseBlockId() { 1587 // Parse the specifier-qualifier-list piece. 1588 DeclSpec DS; 1589 ParseSpecifierQualifierList(DS); 1590 1591 // Parse the block-declarator. 1592 Declarator DeclaratorInfo(DS, Declarator::BlockLiteralContext); 1593 ParseDeclarator(DeclaratorInfo); 1594 1595 // We do this for: ^ __attribute__((noreturn)) {, as DS has the attributes. 1596 DeclaratorInfo.AddAttributes(DS.TakeAttributes(), 1597 SourceLocation()); 1598 1599 if (Tok.is(tok::kw___attribute)) { 1600 SourceLocation Loc; 1601 AttributeList *AttrList = ParseGNUAttributes(&Loc); 1602 DeclaratorInfo.AddAttributes(AttrList, Loc); 1603 } 1604 1605 // Inform sema that we are starting a block. 1606 Actions.ActOnBlockArguments(DeclaratorInfo, CurScope); 1607} 1608 1609/// ParseBlockLiteralExpression - Parse a block literal, which roughly looks 1610/// like ^(int x){ return x+1; } 1611/// 1612/// block-literal: 1613/// [clang] '^' block-args[opt] compound-statement 1614/// [clang] '^' block-id compound-statement 1615/// [clang] block-args: 1616/// [clang] '(' parameter-list ')' 1617/// 1618Parser::OwningExprResult Parser::ParseBlockLiteralExpression() { 1619 assert(Tok.is(tok::caret) && "block literal starts with ^"); 1620 SourceLocation CaretLoc = ConsumeToken(); 1621 1622 PrettyStackTraceLoc CrashInfo(PP.getSourceManager(), CaretLoc, 1623 "block literal parsing"); 1624 1625 // Enter a scope to hold everything within the block. This includes the 1626 // argument decls, decls within the compound expression, etc. This also 1627 // allows determining whether a variable reference inside the block is 1628 // within or outside of the block. 1629 ParseScope BlockScope(this, Scope::BlockScope | Scope::FnScope | 1630 Scope::BreakScope | Scope::ContinueScope | 1631 Scope::DeclScope); 1632 1633 // Inform sema that we are starting a block. 1634 Actions.ActOnBlockStart(CaretLoc, CurScope); 1635 1636 // Parse the return type if present. 1637 DeclSpec DS; 1638 Declarator ParamInfo(DS, Declarator::BlockLiteralContext); 1639 // FIXME: Since the return type isn't actually parsed, it can't be used to 1640 // fill ParamInfo with an initial valid range, so do it manually. 1641 ParamInfo.SetSourceRange(SourceRange(Tok.getLocation(), Tok.getLocation())); 1642 1643 // If this block has arguments, parse them. There is no ambiguity here with 1644 // the expression case, because the expression case requires a parameter list. 1645 if (Tok.is(tok::l_paren)) { 1646 ParseParenDeclarator(ParamInfo); 1647 // Parse the pieces after the identifier as if we had "int(...)". 1648 // SetIdentifier sets the source range end, but in this case we're past 1649 // that location. 1650 SourceLocation Tmp = ParamInfo.getSourceRange().getEnd(); 1651 ParamInfo.SetIdentifier(0, CaretLoc); 1652 ParamInfo.SetRangeEnd(Tmp); 1653 if (ParamInfo.isInvalidType()) { 1654 // If there was an error parsing the arguments, they may have 1655 // tried to use ^(x+y) which requires an argument list. Just 1656 // skip the whole block literal. 1657 Actions.ActOnBlockError(CaretLoc, CurScope); 1658 return ExprError(); 1659 } 1660 1661 if (Tok.is(tok::kw___attribute)) { 1662 SourceLocation Loc; 1663 AttributeList *AttrList = ParseGNUAttributes(&Loc); 1664 ParamInfo.AddAttributes(AttrList, Loc); 1665 } 1666 1667 // Inform sema that we are starting a block. 1668 Actions.ActOnBlockArguments(ParamInfo, CurScope); 1669 } else if (!Tok.is(tok::l_brace)) { 1670 ParseBlockId(); 1671 } else { 1672 // Otherwise, pretend we saw (void). 1673 ParamInfo.AddTypeInfo(DeclaratorChunk::getFunction(true, false, 1674 SourceLocation(), 1675 0, 0, 0, 1676 false, SourceLocation(), 1677 false, 0, 0, 0, 1678 CaretLoc, CaretLoc, 1679 ParamInfo), 1680 CaretLoc); 1681 1682 if (Tok.is(tok::kw___attribute)) { 1683 SourceLocation Loc; 1684 AttributeList *AttrList = ParseGNUAttributes(&Loc); 1685 ParamInfo.AddAttributes(AttrList, Loc); 1686 } 1687 1688 // Inform sema that we are starting a block. 1689 Actions.ActOnBlockArguments(ParamInfo, CurScope); 1690 } 1691 1692 1693 OwningExprResult Result(Actions, true); 1694 if (!Tok.is(tok::l_brace)) { 1695 // Saw something like: ^expr 1696 Diag(Tok, diag::err_expected_expression); 1697 Actions.ActOnBlockError(CaretLoc, CurScope); 1698 return ExprError(); 1699 } 1700 1701 OwningStmtResult Stmt(ParseCompoundStatementBody()); 1702 if (!Stmt.isInvalid()) 1703 Result = Actions.ActOnBlockStmtExpr(CaretLoc, move(Stmt), CurScope); 1704 else 1705 Actions.ActOnBlockError(CaretLoc, CurScope); 1706 return move(Result); 1707} 1708