| //===--- ParseExpr.cpp - Expression Parsing -------------------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements the Expression parsing implementation. Expressions in |
| // C99 basically consist of a bunch of binary operators with unary operators and |
| // other random stuff at the leaves. |
| // |
| // In the C99 grammar, these unary operators bind tightest and are represented |
| // as the 'cast-expression' production. Everything else is either a binary |
| // operator (e.g. '/') or a ternary operator ("?:"). The unary leaves are |
| // handled by ParseCastExpression, the higher level pieces are handled by |
| // ParseBinaryExpression. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "clang/Parse/Parser.h" |
| #include "clang/Basic/Diagnostic.h" |
| #include "llvm/ADT/SmallVector.h" |
| #include "llvm/ADT/SmallString.h" |
| using namespace clang; |
| |
| /// PrecedenceLevels - These are precedences for the binary/ternary operators in |
| /// the C99 grammar. These have been named to relate with the C99 grammar |
| /// productions. Low precedences numbers bind more weakly than high numbers. |
| namespace prec { |
| enum Level { |
| Unknown = 0, // Not binary operator. |
| Comma = 1, // , |
| Assignment = 2, // =, *=, /=, %=, +=, -=, <<=, >>=, &=, ^=, |= |
| Conditional = 3, // ? |
| LogicalOr = 4, // || |
| LogicalAnd = 5, // && |
| InclusiveOr = 6, // | |
| ExclusiveOr = 7, // ^ |
| And = 8, // & |
| Equality = 9, // ==, != |
| Relational = 10, // >=, <=, >, < |
| Shift = 11, // <<, >> |
| Additive = 12, // -, + |
| Multiplicative = 13 // *, /, % |
| }; |
| } |
| |
| |
| /// getBinOpPrecedence - Return the precedence of the specified binary operator |
| /// token. This returns: |
| /// |
| static prec::Level getBinOpPrecedence(tok::TokenKind Kind) { |
| switch (Kind) { |
| default: return prec::Unknown; |
| case tok::comma: return prec::Comma; |
| case tok::equal: |
| case tok::starequal: |
| case tok::slashequal: |
| case tok::percentequal: |
| case tok::plusequal: |
| case tok::minusequal: |
| case tok::lesslessequal: |
| case tok::greatergreaterequal: |
| case tok::ampequal: |
| case tok::caretequal: |
| case tok::pipeequal: return prec::Assignment; |
| case tok::question: return prec::Conditional; |
| case tok::pipepipe: return prec::LogicalOr; |
| case tok::ampamp: return prec::LogicalAnd; |
| case tok::pipe: return prec::InclusiveOr; |
| case tok::caret: return prec::ExclusiveOr; |
| case tok::amp: return prec::And; |
| case tok::exclaimequal: |
| case tok::equalequal: return prec::Equality; |
| case tok::lessequal: |
| case tok::less: |
| case tok::greaterequal: |
| case tok::greater: return prec::Relational; |
| case tok::lessless: |
| case tok::greatergreater: return prec::Shift; |
| case tok::plus: |
| case tok::minus: return prec::Additive; |
| case tok::percent: |
| case tok::slash: |
| case tok::star: return prec::Multiplicative; |
| } |
| } |
| |
| |
| /// ParseExpression - Simple precedence-based parser for binary/ternary |
| /// operators. |
| /// |
| /// Note: we diverge from the C99 grammar when parsing the assignment-expression |
| /// production. C99 specifies that the LHS of an assignment operator should be |
| /// parsed as a unary-expression, but consistency dictates that it be a |
| /// conditional-expession. In practice, the important thing here is that the |
| /// LHS of an assignment has to be an l-value, which productions between |
| /// unary-expression and conditional-expression don't produce. Because we want |
| /// consistency, we parse the LHS as a conditional-expression, then check for |
| /// l-value-ness in semantic analysis stages. |
| /// |
| /// multiplicative-expression: [C99 6.5.5] |
| /// cast-expression |
| /// multiplicative-expression '*' cast-expression |
| /// multiplicative-expression '/' cast-expression |
| /// multiplicative-expression '%' cast-expression |
| /// |
| /// additive-expression: [C99 6.5.6] |
| /// multiplicative-expression |
| /// additive-expression '+' multiplicative-expression |
| /// additive-expression '-' multiplicative-expression |
| /// |
| /// shift-expression: [C99 6.5.7] |
| /// additive-expression |
| /// shift-expression '<<' additive-expression |
| /// shift-expression '>>' additive-expression |
| /// |
| /// relational-expression: [C99 6.5.8] |
| /// shift-expression |
| /// relational-expression '<' shift-expression |
| /// relational-expression '>' shift-expression |
| /// relational-expression '<=' shift-expression |
| /// relational-expression '>=' shift-expression |
| /// |
| /// equality-expression: [C99 6.5.9] |
| /// relational-expression |
| /// equality-expression '==' relational-expression |
| /// equality-expression '!=' relational-expression |
| /// |
| /// AND-expression: [C99 6.5.10] |
| /// equality-expression |
| /// AND-expression '&' equality-expression |
| /// |
| /// exclusive-OR-expression: [C99 6.5.11] |
| /// AND-expression |
| /// exclusive-OR-expression '^' AND-expression |
| /// |
| /// inclusive-OR-expression: [C99 6.5.12] |
| /// exclusive-OR-expression |
| /// inclusive-OR-expression '|' exclusive-OR-expression |
| /// |
| /// logical-AND-expression: [C99 6.5.13] |
| /// inclusive-OR-expression |
| /// logical-AND-expression '&&' inclusive-OR-expression |
| /// |
| /// logical-OR-expression: [C99 6.5.14] |
| /// logical-AND-expression |
| /// logical-OR-expression '||' logical-AND-expression |
| /// |
| /// conditional-expression: [C99 6.5.15] |
| /// logical-OR-expression |
| /// logical-OR-expression '?' expression ':' conditional-expression |
| /// [GNU] logical-OR-expression '?' ':' conditional-expression |
| /// |
| /// assignment-expression: [C99 6.5.16] |
| /// conditional-expression |
| /// unary-expression assignment-operator assignment-expression |
| /// [C++] throw-expression [C++ 15] |
| /// |
| /// assignment-operator: one of |
| /// = *= /= %= += -= <<= >>= &= ^= |= |
| /// |
| /// expression: [C99 6.5.17] |
| /// assignment-expression |
| /// expression ',' assignment-expression |
| /// |
| Parser::ExprResult Parser::ParseExpression() { |
| if (Tok.is(tok::kw_throw)) |
| return ParseThrowExpression(); |
| |
| ExprResult LHS = ParseCastExpression(false); |
| if (LHS.isInvalid) return LHS; |
| |
| return ParseRHSOfBinaryExpression(LHS, prec::Comma); |
| } |
| |
| /// This routine is called when the '@' is seen and consumed. |
| /// Current token is an Identifier and is not a 'try'. This |
| /// routine is necessary to disambiguate @try-statement from, |
| /// for example, @encode-expression. |
| /// |
| Parser::ExprResult Parser::ParseExpressionWithLeadingAt(SourceLocation AtLoc) { |
| ExprResult LHS = ParseObjCAtExpression(AtLoc); |
| if (LHS.isInvalid) return LHS; |
| |
| return ParseRHSOfBinaryExpression(LHS, prec::Comma); |
| } |
| |
| /// ParseAssignmentExpression - Parse an expr that doesn't include commas. |
| /// |
| Parser::ExprResult Parser::ParseAssignmentExpression() { |
| if (Tok.is(tok::kw_throw)) |
| return ParseThrowExpression(); |
| |
| ExprResult LHS = ParseCastExpression(false); |
| if (LHS.isInvalid) return LHS; |
| |
| return ParseRHSOfBinaryExpression(LHS, prec::Assignment); |
| } |
| |
| /// ParseAssignmentExprWithObjCMessageExprStart - Parse an assignment expression |
| /// where part of an objc message send has already been parsed. In this case |
| /// LBracLoc indicates the location of the '[' of the message send, and either |
| /// ReceiverName or ReceiverExpr is non-null indicating the receiver of the |
| /// message. |
| /// |
| /// Since this handles full assignment-expression's, it handles postfix |
| /// expressions and other binary operators for these expressions as well. |
| Parser::ExprResult |
| Parser::ParseAssignmentExprWithObjCMessageExprStart(SourceLocation LBracLoc, |
| IdentifierInfo *ReceiverName, |
| ExprTy *ReceiverExpr) { |
| ExprResult R = ParseObjCMessageExpressionBody(LBracLoc, ReceiverName, |
| ReceiverExpr); |
| if (R.isInvalid) return R; |
| R = ParsePostfixExpressionSuffix(R); |
| if (R.isInvalid) return R; |
| return ParseRHSOfBinaryExpression(R, 2); |
| } |
| |
| |
| Parser::ExprResult Parser::ParseConstantExpression() { |
| ExprResult LHS = ParseCastExpression(false); |
| if (LHS.isInvalid) return LHS; |
| |
| return ParseRHSOfBinaryExpression(LHS, prec::Conditional); |
| } |
| |
| /// ParseExpressionWithLeadingIdentifier - This special purpose method is used |
| /// in contexts where we have already consumed an identifier (which we saved in |
| /// 'IdTok'), then discovered that the identifier was really the leading token |
| /// of part of an expression. For example, in "A[1]+B", we consumed "A" (which |
| /// is now in 'IdTok') and the current token is "[". |
| Parser::ExprResult Parser:: |
| ParseExpressionWithLeadingIdentifier(const Token &IdTok) { |
| // We know that 'IdTok' must correspond to this production: |
| // primary-expression: identifier |
| |
| // Let the actions module handle the identifier. |
| ExprResult Res = Actions.ActOnIdentifierExpr(CurScope, IdTok.getLocation(), |
| *IdTok.getIdentifierInfo(), |
| Tok.is(tok::l_paren)); |
| |
| // Because we have to parse an entire cast-expression before starting the |
| // ParseRHSOfBinaryExpression method (which parses any trailing binops), we |
| // need to handle the 'postfix-expression' rules. We do this by invoking |
| // ParsePostfixExpressionSuffix to consume any postfix-expression suffixes: |
| Res = ParsePostfixExpressionSuffix(Res); |
| if (Res.isInvalid) return Res; |
| |
| // At this point, the "A[1]" part of "A[1]+B" has been consumed. Once this is |
| // done, we know we don't have to do anything for cast-expression, because the |
| // only non-postfix-expression production starts with a '(' token, and we know |
| // we have an identifier. As such, we can invoke ParseRHSOfBinaryExpression |
| // to consume any trailing operators (e.g. "+" in this example) and connected |
| // chunks of the expression. |
| return ParseRHSOfBinaryExpression(Res, prec::Comma); |
| } |
| |
| /// ParseExpressionWithLeadingIdentifier - This special purpose method is used |
| /// in contexts where we have already consumed an identifier (which we saved in |
| /// 'IdTok'), then discovered that the identifier was really the leading token |
| /// of part of an assignment-expression. For example, in "A[1]+B", we consumed |
| /// "A" (which is now in 'IdTok') and the current token is "[". |
| Parser::ExprResult Parser:: |
| ParseAssignmentExprWithLeadingIdentifier(const Token &IdTok) { |
| // We know that 'IdTok' must correspond to this production: |
| // primary-expression: identifier |
| |
| // Let the actions module handle the identifier. |
| ExprResult Res = Actions.ActOnIdentifierExpr(CurScope, IdTok.getLocation(), |
| *IdTok.getIdentifierInfo(), |
| Tok.is(tok::l_paren)); |
| |
| // Because we have to parse an entire cast-expression before starting the |
| // ParseRHSOfBinaryExpression method (which parses any trailing binops), we |
| // need to handle the 'postfix-expression' rules. We do this by invoking |
| // ParsePostfixExpressionSuffix to consume any postfix-expression suffixes: |
| Res = ParsePostfixExpressionSuffix(Res); |
| if (Res.isInvalid) return Res; |
| |
| // At this point, the "A[1]" part of "A[1]+B" has been consumed. Once this is |
| // done, we know we don't have to do anything for cast-expression, because the |
| // only non-postfix-expression production starts with a '(' token, and we know |
| // we have an identifier. As such, we can invoke ParseRHSOfBinaryExpression |
| // to consume any trailing operators (e.g. "+" in this example) and connected |
| // chunks of the expression. |
| return ParseRHSOfBinaryExpression(Res, prec::Assignment); |
| } |
| |
| |
| /// ParseRHSOfBinaryExpression - Parse a binary expression that starts with |
| /// LHS and has a precedence of at least MinPrec. |
| Parser::ExprResult |
| Parser::ParseRHSOfBinaryExpression(ExprResult LHS, unsigned MinPrec) { |
| unsigned NextTokPrec = getBinOpPrecedence(Tok.getKind()); |
| SourceLocation ColonLoc; |
| |
| while (1) { |
| // If this token has a lower precedence than we are allowed to parse (e.g. |
| // because we are called recursively, or because the token is not a binop), |
| // then we are done! |
| if (NextTokPrec < MinPrec) |
| return LHS; |
| |
| // Consume the operator, saving the operator token for error reporting. |
| Token OpToken = Tok; |
| ConsumeToken(); |
| |
| // Special case handling for the ternary operator. |
| ExprResult TernaryMiddle(true); |
| if (NextTokPrec == prec::Conditional) { |
| if (Tok.isNot(tok::colon)) { |
| // Handle this production specially: |
| // logical-OR-expression '?' expression ':' conditional-expression |
| // In particular, the RHS of the '?' is 'expression', not |
| // 'logical-OR-expression' as we might expect. |
| TernaryMiddle = ParseExpression(); |
| if (TernaryMiddle.isInvalid) { |
| Actions.DeleteExpr(LHS.Val); |
| return TernaryMiddle; |
| } |
| } else { |
| // Special case handling of "X ? Y : Z" where Y is empty: |
| // logical-OR-expression '?' ':' conditional-expression [GNU] |
| TernaryMiddle = ExprResult(false); |
| Diag(Tok, diag::ext_gnu_conditional_expr); |
| } |
| |
| if (Tok.isNot(tok::colon)) { |
| Diag(Tok, diag::err_expected_colon); |
| Diag(OpToken, diag::err_matching, "?"); |
| Actions.DeleteExpr(LHS.Val); |
| Actions.DeleteExpr(TernaryMiddle.Val); |
| return ExprResult(true); |
| } |
| |
| // Eat the colon. |
| ColonLoc = ConsumeToken(); |
| } |
| |
| // Parse another leaf here for the RHS of the operator. |
| ExprResult RHS = ParseCastExpression(false); |
| if (RHS.isInvalid) { |
| Actions.DeleteExpr(LHS.Val); |
| Actions.DeleteExpr(TernaryMiddle.Val); |
| return RHS; |
| } |
| |
| // Remember the precedence of this operator and get the precedence of the |
| // operator immediately to the right of the RHS. |
| unsigned ThisPrec = NextTokPrec; |
| NextTokPrec = getBinOpPrecedence(Tok.getKind()); |
| |
| // Assignment and conditional expressions are right-associative. |
| bool isRightAssoc = ThisPrec == prec::Conditional || |
| ThisPrec == prec::Assignment; |
| |
| // Get the precedence of the operator to the right of the RHS. If it binds |
| // more tightly with RHS than we do, evaluate it completely first. |
| if (ThisPrec < NextTokPrec || |
| (ThisPrec == NextTokPrec && isRightAssoc)) { |
| // If this is left-associative, only parse things on the RHS that bind |
| // more tightly than the current operator. If it is left-associative, it |
| // is okay, to bind exactly as tightly. For example, compile A=B=C=D as |
| // A=(B=(C=D)), where each paren is a level of recursion here. |
| RHS = ParseRHSOfBinaryExpression(RHS, ThisPrec + !isRightAssoc); |
| if (RHS.isInvalid) { |
| Actions.DeleteExpr(LHS.Val); |
| Actions.DeleteExpr(TernaryMiddle.Val); |
| return RHS; |
| } |
| |
| NextTokPrec = getBinOpPrecedence(Tok.getKind()); |
| } |
| assert(NextTokPrec <= ThisPrec && "Recursion didn't work!"); |
| |
| if (!LHS.isInvalid) { |
| // Combine the LHS and RHS into the LHS (e.g. build AST). |
| if (TernaryMiddle.isInvalid) |
| LHS = Actions.ActOnBinOp(OpToken.getLocation(), OpToken.getKind(), |
| LHS.Val, RHS.Val); |
| else |
| LHS = Actions.ActOnConditionalOp(OpToken.getLocation(), ColonLoc, |
| LHS.Val, TernaryMiddle.Val, RHS.Val); |
| } else { |
| // We had a semantic error on the LHS. Just free the RHS and continue. |
| Actions.DeleteExpr(TernaryMiddle.Val); |
| Actions.DeleteExpr(RHS.Val); |
| } |
| } |
| } |
| |
| /// ParseCastExpression - Parse a cast-expression, or, if isUnaryExpression is |
| /// true, parse a unary-expression. |
| /// |
| /// cast-expression: [C99 6.5.4] |
| /// unary-expression |
| /// '(' type-name ')' cast-expression |
| /// |
| /// unary-expression: [C99 6.5.3] |
| /// postfix-expression |
| /// '++' unary-expression |
| /// '--' unary-expression |
| /// unary-operator cast-expression |
| /// 'sizeof' unary-expression |
| /// 'sizeof' '(' type-name ')' |
| /// [GNU] '__alignof' unary-expression |
| /// [GNU] '__alignof' '(' type-name ')' |
| /// [GNU] '&&' identifier |
| /// |
| /// unary-operator: one of |
| /// '&' '*' '+' '-' '~' '!' |
| /// [GNU] '__extension__' '__real' '__imag' |
| /// |
| /// primary-expression: [C99 6.5.1] |
| /// identifier |
| /// constant |
| /// string-literal |
| /// [C++] boolean-literal [C++ 2.13.5] |
| /// '(' expression ')' |
| /// '__func__' [C99 6.4.2.2] |
| /// [GNU] '__FUNCTION__' |
| /// [GNU] '__PRETTY_FUNCTION__' |
| /// [GNU] '(' compound-statement ')' |
| /// [GNU] '__builtin_va_arg' '(' assignment-expression ',' type-name ')' |
| /// [GNU] '__builtin_offsetof' '(' type-name ',' offsetof-member-designator')' |
| /// [GNU] '__builtin_choose_expr' '(' assign-expr ',' assign-expr ',' |
| /// assign-expr ')' |
| /// [GNU] '__builtin_types_compatible_p' '(' type-name ',' type-name ')' |
| /// [OBJC] '[' objc-message-expr ']' |
| /// [OBJC] '@selector' '(' objc-selector-arg ')' |
| /// [OBJC] '@protocol' '(' identifier ')' |
| /// [OBJC] '@encode' '(' type-name ')' |
| /// [OBJC] objc-string-literal |
| /// [C++] 'const_cast' '<' type-name '>' '(' expression ')' [C++ 5.2p1] |
| /// [C++] 'dynamic_cast' '<' type-name '>' '(' expression ')' [C++ 5.2p1] |
| /// [C++] 'reinterpret_cast' '<' type-name '>' '(' expression ')' [C++ 5.2p1] |
| /// [C++] 'static_cast' '<' type-name '>' '(' expression ')' [C++ 5.2p1] |
| /// |
| /// constant: [C99 6.4.4] |
| /// integer-constant |
| /// floating-constant |
| /// enumeration-constant -> identifier |
| /// character-constant |
| /// |
| Parser::ExprResult Parser::ParseCastExpression(bool isUnaryExpression) { |
| ExprResult Res; |
| tok::TokenKind SavedKind = Tok.getKind(); |
| |
| // This handles all of cast-expression, unary-expression, postfix-expression, |
| // and primary-expression. We handle them together like this for efficiency |
| // and to simplify handling of an expression starting with a '(' token: which |
| // may be one of a parenthesized expression, cast-expression, compound literal |
| // expression, or statement expression. |
| // |
| // If the parsed tokens consist of a primary-expression, the cases below |
| // call ParsePostfixExpressionSuffix to handle the postfix expression |
| // suffixes. Cases that cannot be followed by postfix exprs should |
| // return without invoking ParsePostfixExpressionSuffix. |
| switch (SavedKind) { |
| case tok::l_paren: { |
| // If this expression is limited to being a unary-expression, the parent can |
| // not start a cast expression. |
| ParenParseOption ParenExprType = |
| isUnaryExpression ? CompoundLiteral : CastExpr; |
| TypeTy *CastTy; |
| SourceLocation LParenLoc = Tok.getLocation(); |
| SourceLocation RParenLoc; |
| Res = ParseParenExpression(ParenExprType, CastTy, RParenLoc); |
| if (Res.isInvalid) return Res; |
| |
| switch (ParenExprType) { |
| case SimpleExpr: break; // Nothing else to do. |
| case CompoundStmt: break; // Nothing else to do. |
| case CompoundLiteral: |
| // We parsed '(' type-name ')' '{' ... '}'. If any suffixes of |
| // postfix-expression exist, parse them now. |
| break; |
| case CastExpr: |
| // We parsed '(' type-name ')' and the thing after it wasn't a '{'. Parse |
| // the cast-expression that follows it next. |
| // TODO: For cast expression with CastTy. |
| Res = ParseCastExpression(false); |
| if (!Res.isInvalid) |
| Res = Actions.ActOnCastExpr(LParenLoc, CastTy, RParenLoc, Res.Val); |
| return Res; |
| } |
| |
| // These can be followed by postfix-expr pieces. |
| return ParsePostfixExpressionSuffix(Res); |
| } |
| |
| // primary-expression |
| case tok::numeric_constant: |
| // constant: integer-constant |
| // constant: floating-constant |
| |
| Res = Actions.ActOnNumericConstant(Tok); |
| ConsumeToken(); |
| |
| // These can be followed by postfix-expr pieces. |
| return ParsePostfixExpressionSuffix(Res); |
| |
| case tok::kw_true: |
| case tok::kw_false: |
| return ParseCXXBoolLiteral(); |
| |
| case tok::identifier: { // primary-expression: identifier |
| // constant: enumeration-constant |
| // Consume the identifier so that we can see if it is followed by a '('. |
| // Function designators are allowed to be undeclared (C99 6.5.1p2), so we |
| // need to know whether or not this identifier is a function designator or |
| // not. |
| IdentifierInfo &II = *Tok.getIdentifierInfo(); |
| SourceLocation L = ConsumeToken(); |
| Res = Actions.ActOnIdentifierExpr(CurScope, L, II, Tok.is(tok::l_paren)); |
| // These can be followed by postfix-expr pieces. |
| return ParsePostfixExpressionSuffix(Res); |
| } |
| case tok::char_constant: // constant: character-constant |
| Res = Actions.ActOnCharacterConstant(Tok); |
| ConsumeToken(); |
| // These can be followed by postfix-expr pieces. |
| return ParsePostfixExpressionSuffix(Res); |
| case tok::kw___func__: // primary-expression: __func__ [C99 6.4.2.2] |
| case tok::kw___FUNCTION__: // primary-expression: __FUNCTION__ [GNU] |
| case tok::kw___PRETTY_FUNCTION__: // primary-expression: __P..Y_F..N__ [GNU] |
| Res = Actions.ActOnPreDefinedExpr(Tok.getLocation(), SavedKind); |
| ConsumeToken(); |
| // These can be followed by postfix-expr pieces. |
| return ParsePostfixExpressionSuffix(Res); |
| case tok::string_literal: // primary-expression: string-literal |
| case tok::wide_string_literal: |
| Res = ParseStringLiteralExpression(); |
| if (Res.isInvalid) return Res; |
| // This can be followed by postfix-expr pieces (e.g. "foo"[1]). |
| return ParsePostfixExpressionSuffix(Res); |
| case tok::kw___builtin_va_arg: |
| case tok::kw___builtin_offsetof: |
| case tok::kw___builtin_choose_expr: |
| case tok::kw___builtin_overload: |
| case tok::kw___builtin_types_compatible_p: |
| return ParseBuiltinPrimaryExpression(); |
| case tok::plusplus: // unary-expression: '++' unary-expression |
| case tok::minusminus: { // unary-expression: '--' unary-expression |
| SourceLocation SavedLoc = ConsumeToken(); |
| Res = ParseCastExpression(true); |
| if (!Res.isInvalid) |
| Res = Actions.ActOnUnaryOp(SavedLoc, SavedKind, Res.Val); |
| return Res; |
| } |
| case tok::amp: // unary-expression: '&' cast-expression |
| case tok::star: // unary-expression: '*' cast-expression |
| case tok::plus: // unary-expression: '+' cast-expression |
| case tok::minus: // unary-expression: '-' cast-expression |
| case tok::tilde: // unary-expression: '~' cast-expression |
| case tok::exclaim: // unary-expression: '!' cast-expression |
| case tok::kw___real: // unary-expression: '__real' cast-expression [GNU] |
| case tok::kw___imag: { // unary-expression: '__imag' cast-expression [GNU] |
| SourceLocation SavedLoc = ConsumeToken(); |
| Res = ParseCastExpression(false); |
| if (!Res.isInvalid) |
| Res = Actions.ActOnUnaryOp(SavedLoc, SavedKind, Res.Val); |
| return Res; |
| } |
| |
| case tok::kw___extension__:{//unary-expression:'__extension__' cast-expr [GNU] |
| // __extension__ silences extension warnings in the subexpression. |
| bool SavedExtWarn = Diags.getWarnOnExtensions(); |
| Diags.setWarnOnExtensions(false); |
| SourceLocation SavedLoc = ConsumeToken(); |
| Res = ParseCastExpression(false); |
| if (!Res.isInvalid) |
| Res = Actions.ActOnUnaryOp(SavedLoc, SavedKind, Res.Val); |
| Diags.setWarnOnExtensions(SavedExtWarn); |
| return Res; |
| } |
| case tok::kw_sizeof: // unary-expression: 'sizeof' unary-expression |
| // unary-expression: 'sizeof' '(' type-name ')' |
| case tok::kw___alignof: // unary-expression: '__alignof' unary-expression |
| // unary-expression: '__alignof' '(' type-name ')' |
| return ParseSizeofAlignofExpression(); |
| case tok::ampamp: { // unary-expression: '&&' identifier |
| SourceLocation AmpAmpLoc = ConsumeToken(); |
| if (Tok.isNot(tok::identifier)) { |
| Diag(Tok, diag::err_expected_ident); |
| return ExprResult(true); |
| } |
| |
| Diag(AmpAmpLoc, diag::ext_gnu_address_of_label); |
| Res = Actions.ActOnAddrLabel(AmpAmpLoc, Tok.getLocation(), |
| Tok.getIdentifierInfo()); |
| ConsumeToken(); |
| return Res; |
| } |
| case tok::kw_const_cast: |
| case tok::kw_dynamic_cast: |
| case tok::kw_reinterpret_cast: |
| case tok::kw_static_cast: |
| return ParseCXXCasts(); |
| case tok::kw_this: |
| return ParseCXXThis(); |
| case tok::at: { |
| SourceLocation AtLoc = ConsumeToken(); |
| return ParseObjCAtExpression(AtLoc); |
| } |
| case tok::l_square: |
| // These can be followed by postfix-expr pieces. |
| if (getLang().ObjC1) |
| return ParsePostfixExpressionSuffix(ParseObjCMessageExpression()); |
| // FALL THROUGH. |
| default: |
| Diag(Tok, diag::err_expected_expression); |
| return ExprResult(true); |
| } |
| |
| // unreachable. |
| abort(); |
| } |
| |
| /// ParsePostfixExpressionSuffix - Once the leading part of a postfix-expression |
| /// is parsed, this method parses any suffixes that apply. |
| /// |
| /// postfix-expression: [C99 6.5.2] |
| /// primary-expression |
| /// postfix-expression '[' expression ']' |
| /// postfix-expression '(' argument-expression-list[opt] ')' |
| /// postfix-expression '.' identifier |
| /// postfix-expression '->' identifier |
| /// postfix-expression '++' |
| /// postfix-expression '--' |
| /// '(' type-name ')' '{' initializer-list '}' |
| /// '(' type-name ')' '{' initializer-list ',' '}' |
| /// |
| /// argument-expression-list: [C99 6.5.2] |
| /// argument-expression |
| /// argument-expression-list ',' assignment-expression |
| /// |
| Parser::ExprResult Parser::ParsePostfixExpressionSuffix(ExprResult LHS) { |
| |
| // Now that the primary-expression piece of the postfix-expression has been |
| // parsed, see if there are any postfix-expression pieces here. |
| SourceLocation Loc; |
| while (1) { |
| switch (Tok.getKind()) { |
| default: // Not a postfix-expression suffix. |
| return LHS; |
| case tok::l_square: { // postfix-expression: p-e '[' expression ']' |
| Loc = ConsumeBracket(); |
| ExprResult Idx = ParseExpression(); |
| |
| SourceLocation RLoc = Tok.getLocation(); |
| |
| if (!LHS.isInvalid && !Idx.isInvalid && Tok.is(tok::r_square)) |
| LHS = Actions.ActOnArraySubscriptExpr(LHS.Val, Loc, Idx.Val, RLoc); |
| else |
| LHS = ExprResult(true); |
| |
| // Match the ']'. |
| MatchRHSPunctuation(tok::r_square, Loc); |
| break; |
| } |
| |
| case tok::l_paren: { // p-e: p-e '(' argument-expression-list[opt] ')' |
| llvm::SmallVector<ExprTy*, 8> ArgExprs; |
| llvm::SmallVector<SourceLocation, 8> CommaLocs; |
| |
| Loc = ConsumeParen(); |
| |
| if (Tok.isNot(tok::r_paren)) { |
| while (1) { |
| ExprResult ArgExpr = ParseAssignmentExpression(); |
| if (ArgExpr.isInvalid) { |
| SkipUntil(tok::r_paren); |
| return ExprResult(true); |
| } else |
| ArgExprs.push_back(ArgExpr.Val); |
| |
| if (Tok.isNot(tok::comma)) |
| break; |
| // Move to the next argument, remember where the comma was. |
| CommaLocs.push_back(ConsumeToken()); |
| } |
| } |
| |
| // Match the ')'. |
| if (!LHS.isInvalid && Tok.is(tok::r_paren)) { |
| assert((ArgExprs.size() == 0 || ArgExprs.size()-1 == CommaLocs.size())&& |
| "Unexpected number of commas!"); |
| LHS = Actions.ActOnCallExpr(LHS.Val, Loc, &ArgExprs[0], ArgExprs.size(), |
| &CommaLocs[0], Tok.getLocation()); |
| } |
| |
| MatchRHSPunctuation(tok::r_paren, Loc); |
| break; |
| } |
| case tok::arrow: // postfix-expression: p-e '->' identifier |
| case tok::period: { // postfix-expression: p-e '.' identifier |
| tok::TokenKind OpKind = Tok.getKind(); |
| SourceLocation OpLoc = ConsumeToken(); // Eat the "." or "->" token. |
| |
| if (Tok.isNot(tok::identifier)) { |
| Diag(Tok, diag::err_expected_ident); |
| return ExprResult(true); |
| } |
| |
| if (!LHS.isInvalid) |
| LHS = Actions.ActOnMemberReferenceExpr(LHS.Val, OpLoc, OpKind, |
| Tok.getLocation(), |
| *Tok.getIdentifierInfo()); |
| ConsumeToken(); |
| break; |
| } |
| case tok::plusplus: // postfix-expression: postfix-expression '++' |
| case tok::minusminus: // postfix-expression: postfix-expression '--' |
| if (!LHS.isInvalid) |
| LHS = Actions.ActOnPostfixUnaryOp(Tok.getLocation(), Tok.getKind(), |
| LHS.Val); |
| ConsumeToken(); |
| break; |
| } |
| } |
| } |
| |
| |
| /// ParseSizeofAlignofExpression - Parse a sizeof or alignof expression. |
| /// unary-expression: [C99 6.5.3] |
| /// 'sizeof' unary-expression |
| /// 'sizeof' '(' type-name ')' |
| /// [GNU] '__alignof' unary-expression |
| /// [GNU] '__alignof' '(' type-name ')' |
| Parser::ExprResult Parser::ParseSizeofAlignofExpression() { |
| assert((Tok.is(tok::kw_sizeof) || Tok.is(tok::kw___alignof)) && |
| "Not a sizeof/alignof expression!"); |
| Token OpTok = Tok; |
| ConsumeToken(); |
| |
| // If the operand doesn't start with an '(', it must be an expression. |
| ExprResult Operand; |
| if (Tok.isNot(tok::l_paren)) { |
| Operand = ParseCastExpression(true); |
| } else { |
| // If it starts with a '(', we know that it is either a parenthesized |
| // type-name, or it is a unary-expression that starts with a compound |
| // literal, or starts with a primary-expression that is a parenthesized |
| // expression. |
| ParenParseOption ExprType = CastExpr; |
| TypeTy *CastTy; |
| SourceLocation LParenLoc = Tok.getLocation(), RParenLoc; |
| Operand = ParseParenExpression(ExprType, CastTy, RParenLoc); |
| |
| // If ParseParenExpression parsed a '(typename)' sequence only, the this is |
| // sizeof/alignof a type. Otherwise, it is sizeof/alignof an expression. |
| if (ExprType == CastExpr) |
| return Actions.ActOnSizeOfAlignOfTypeExpr(OpTok.getLocation(), |
| OpTok.is(tok::kw_sizeof), |
| LParenLoc, CastTy, RParenLoc); |
| |
| // If this is a parenthesized expression, it is the start of a |
| // unary-expression, but doesn't include any postfix pieces. Parse these |
| // now if present. |
| Operand = ParsePostfixExpressionSuffix(Operand); |
| } |
| |
| // If we get here, the operand to the sizeof/alignof was an expresion. |
| if (!Operand.isInvalid) |
| Operand = Actions.ActOnUnaryOp(OpTok.getLocation(), OpTok.getKind(), |
| Operand.Val); |
| return Operand; |
| } |
| |
| /// ParseBuiltinPrimaryExpression |
| /// |
| /// primary-expression: [C99 6.5.1] |
| /// [GNU] '__builtin_va_arg' '(' assignment-expression ',' type-name ')' |
| /// [GNU] '__builtin_offsetof' '(' type-name ',' offsetof-member-designator')' |
| /// [GNU] '__builtin_choose_expr' '(' assign-expr ',' assign-expr ',' |
| /// assign-expr ')' |
| /// [GNU] '__builtin_types_compatible_p' '(' type-name ',' type-name ')' |
| /// [CLANG] '__builtin_overload' '(' expr (',' expr)* ')' |
| /// |
| /// [GNU] offsetof-member-designator: |
| /// [GNU] identifier |
| /// [GNU] offsetof-member-designator '.' identifier |
| /// [GNU] offsetof-member-designator '[' expression ']' |
| /// |
| Parser::ExprResult Parser::ParseBuiltinPrimaryExpression() { |
| ExprResult Res(false); |
| const IdentifierInfo *BuiltinII = Tok.getIdentifierInfo(); |
| |
| tok::TokenKind T = Tok.getKind(); |
| SourceLocation StartLoc = ConsumeToken(); // Eat the builtin identifier. |
| |
| // All of these start with an open paren. |
| if (Tok.isNot(tok::l_paren)) { |
| Diag(Tok, diag::err_expected_lparen_after, BuiltinII->getName()); |
| return ExprResult(true); |
| } |
| |
| SourceLocation LParenLoc = ConsumeParen(); |
| // TODO: Build AST. |
| |
| switch (T) { |
| default: assert(0 && "Not a builtin primary expression!"); |
| case tok::kw___builtin_va_arg: { |
| ExprResult Expr = ParseAssignmentExpression(); |
| if (Expr.isInvalid) { |
| SkipUntil(tok::r_paren); |
| return Res; |
| } |
| |
| if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "",tok::r_paren)) |
| return ExprResult(true); |
| |
| TypeTy *Ty = ParseTypeName(); |
| |
| if (Tok.isNot(tok::r_paren)) { |
| Diag(Tok, diag::err_expected_rparen); |
| return ExprResult(true); |
| } |
| Res = Actions.ActOnVAArg(StartLoc, Expr.Val, Ty, ConsumeParen()); |
| break; |
| } |
| case tok::kw___builtin_offsetof: { |
| SourceLocation TypeLoc = Tok.getLocation(); |
| TypeTy *Ty = ParseTypeName(); |
| |
| if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "",tok::r_paren)) |
| return ExprResult(true); |
| |
| // We must have at least one identifier here. |
| if (Tok.isNot(tok::identifier)) { |
| Diag(Tok, diag::err_expected_ident); |
| SkipUntil(tok::r_paren); |
| return true; |
| } |
| |
| // Keep track of the various subcomponents we see. |
| llvm::SmallVector<Action::OffsetOfComponent, 4> Comps; |
| |
| Comps.push_back(Action::OffsetOfComponent()); |
| Comps.back().isBrackets = false; |
| Comps.back().U.IdentInfo = Tok.getIdentifierInfo(); |
| Comps.back().LocStart = Comps.back().LocEnd = ConsumeToken(); |
| |
| while (1) { |
| if (Tok.is(tok::period)) { |
| // offsetof-member-designator: offsetof-member-designator '.' identifier |
| Comps.push_back(Action::OffsetOfComponent()); |
| Comps.back().isBrackets = false; |
| Comps.back().LocStart = ConsumeToken(); |
| |
| if (Tok.isNot(tok::identifier)) { |
| Diag(Tok, diag::err_expected_ident); |
| SkipUntil(tok::r_paren); |
| return true; |
| } |
| Comps.back().U.IdentInfo = Tok.getIdentifierInfo(); |
| Comps.back().LocEnd = ConsumeToken(); |
| |
| } else if (Tok.is(tok::l_square)) { |
| // offsetof-member-designator: offsetof-member-design '[' expression ']' |
| Comps.push_back(Action::OffsetOfComponent()); |
| Comps.back().isBrackets = true; |
| Comps.back().LocStart = ConsumeBracket(); |
| Res = ParseExpression(); |
| if (Res.isInvalid) { |
| SkipUntil(tok::r_paren); |
| return Res; |
| } |
| Comps.back().U.E = Res.Val; |
| |
| Comps.back().LocEnd = |
| MatchRHSPunctuation(tok::r_square, Comps.back().LocStart); |
| } else if (Tok.is(tok::r_paren)) { |
| Res = Actions.ActOnBuiltinOffsetOf(StartLoc, TypeLoc, Ty, &Comps[0], |
| Comps.size(), ConsumeParen()); |
| break; |
| } else { |
| // Error occurred. |
| return ExprResult(true); |
| } |
| } |
| break; |
| } |
| case tok::kw___builtin_choose_expr: { |
| ExprResult Cond = ParseAssignmentExpression(); |
| if (Cond.isInvalid) { |
| SkipUntil(tok::r_paren); |
| return Cond; |
| } |
| if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "",tok::r_paren)) |
| return ExprResult(true); |
| |
| ExprResult Expr1 = ParseAssignmentExpression(); |
| if (Expr1.isInvalid) { |
| SkipUntil(tok::r_paren); |
| return Expr1; |
| } |
| if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "",tok::r_paren)) |
| return ExprResult(true); |
| |
| ExprResult Expr2 = ParseAssignmentExpression(); |
| if (Expr2.isInvalid) { |
| SkipUntil(tok::r_paren); |
| return Expr2; |
| } |
| if (Tok.isNot(tok::r_paren)) { |
| Diag(Tok, diag::err_expected_rparen); |
| return ExprResult(true); |
| } |
| Res = Actions.ActOnChooseExpr(StartLoc, Cond.Val, Expr1.Val, Expr2.Val, |
| ConsumeParen()); |
| break; |
| } |
| case tok::kw___builtin_overload: { |
| llvm::SmallVector<ExprTy*, 8> ArgExprs; |
| llvm::SmallVector<SourceLocation, 8> CommaLocs; |
| |
| // For each iteration through the loop look for assign-expr followed by a |
| // comma. If there is no comma, break and attempt to match r-paren. |
| if (Tok.isNot(tok::r_paren)) { |
| while (1) { |
| ExprResult ArgExpr = ParseAssignmentExpression(); |
| if (ArgExpr.isInvalid) { |
| SkipUntil(tok::r_paren); |
| return ExprResult(true); |
| } else |
| ArgExprs.push_back(ArgExpr.Val); |
| |
| if (Tok.isNot(tok::comma)) |
| break; |
| // Move to the next argument, remember where the comma was. |
| CommaLocs.push_back(ConsumeToken()); |
| } |
| } |
| |
| // Attempt to consume the r-paren |
| if (Tok.isNot(tok::r_paren)) { |
| Diag(Tok, diag::err_expected_rparen); |
| SkipUntil(tok::r_paren); |
| return ExprResult(true); |
| } |
| Res = Actions.ActOnOverloadExpr(&ArgExprs[0], ArgExprs.size(), |
| &CommaLocs[0], StartLoc, ConsumeParen()); |
| break; |
| } |
| case tok::kw___builtin_types_compatible_p: |
| TypeTy *Ty1 = ParseTypeName(); |
| |
| if (ExpectAndConsume(tok::comma, diag::err_expected_comma, "",tok::r_paren)) |
| return ExprResult(true); |
| |
| TypeTy *Ty2 = ParseTypeName(); |
| |
| if (Tok.isNot(tok::r_paren)) { |
| Diag(Tok, diag::err_expected_rparen); |
| return ExprResult(true); |
| } |
| Res = Actions.ActOnTypesCompatibleExpr(StartLoc, Ty1, Ty2, ConsumeParen()); |
| break; |
| } |
| |
| // These can be followed by postfix-expr pieces because they are |
| // primary-expressions. |
| return ParsePostfixExpressionSuffix(Res); |
| } |
| |
| /// ParseParenExpression - This parses the unit that starts with a '(' token, |
| /// based on what is allowed by ExprType. The actual thing parsed is returned |
| /// in ExprType. |
| /// |
| /// primary-expression: [C99 6.5.1] |
| /// '(' expression ')' |
| /// [GNU] '(' compound-statement ')' (if !ParenExprOnly) |
| /// postfix-expression: [C99 6.5.2] |
| /// '(' type-name ')' '{' initializer-list '}' |
| /// '(' type-name ')' '{' initializer-list ',' '}' |
| /// cast-expression: [C99 6.5.4] |
| /// '(' type-name ')' cast-expression |
| /// |
| Parser::ExprResult Parser::ParseParenExpression(ParenParseOption &ExprType, |
| TypeTy *&CastTy, |
| SourceLocation &RParenLoc) { |
| assert(Tok.is(tok::l_paren) && "Not a paren expr!"); |
| SourceLocation OpenLoc = ConsumeParen(); |
| ExprResult Result(true); |
| CastTy = 0; |
| |
| if (ExprType >= CompoundStmt && Tok.is(tok::l_brace)) { |
| Diag(Tok, diag::ext_gnu_statement_expr); |
| Parser::StmtResult Stmt = ParseCompoundStatement(true); |
| ExprType = CompoundStmt; |
| |
| // If the substmt parsed correctly, build the AST node. |
| if (!Stmt.isInvalid && Tok.is(tok::r_paren)) |
| Result = Actions.ActOnStmtExpr(OpenLoc, Stmt.Val, Tok.getLocation()); |
| |
| } else if (ExprType >= CompoundLiteral && isTypeSpecifierQualifier()) { |
| // Otherwise, this is a compound literal expression or cast expression. |
| TypeTy *Ty = ParseTypeName(); |
| |
| // Match the ')'. |
| if (Tok.is(tok::r_paren)) |
| RParenLoc = ConsumeParen(); |
| else |
| MatchRHSPunctuation(tok::r_paren, OpenLoc); |
| |
| if (Tok.is(tok::l_brace)) { |
| if (!getLang().C99) // Compound literals don't exist in C90. |
| Diag(OpenLoc, diag::ext_c99_compound_literal); |
| Result = ParseInitializer(); |
| ExprType = CompoundLiteral; |
| if (!Result.isInvalid) |
| return Actions.ActOnCompoundLiteral(OpenLoc, Ty, RParenLoc, Result.Val); |
| } else if (ExprType == CastExpr) { |
| // Note that this doesn't parse the subsequence cast-expression, it just |
| // returns the parsed type to the callee. |
| ExprType = CastExpr; |
| CastTy = Ty; |
| return ExprResult(false); |
| } else { |
| Diag(Tok, diag::err_expected_lbrace_in_compound_literal); |
| return ExprResult(true); |
| } |
| return Result; |
| } else { |
| Result = ParseExpression(); |
| ExprType = SimpleExpr; |
| if (!Result.isInvalid && Tok.is(tok::r_paren)) |
| Result = Actions.ActOnParenExpr(OpenLoc, Tok.getLocation(), Result.Val); |
| } |
| |
| // Match the ')'. |
| if (Result.isInvalid) |
| SkipUntil(tok::r_paren); |
| else { |
| if (Tok.is(tok::r_paren)) |
| RParenLoc = ConsumeParen(); |
| else |
| MatchRHSPunctuation(tok::r_paren, OpenLoc); |
| } |
| |
| return Result; |
| } |
| |
| /// ParseStringLiteralExpression - This handles the various token types that |
| /// form string literals, and also handles string concatenation [C99 5.1.1.2, |
| /// translation phase #6]. |
| /// |
| /// primary-expression: [C99 6.5.1] |
| /// string-literal |
| Parser::ExprResult Parser::ParseStringLiteralExpression() { |
| assert(isTokenStringLiteral() && "Not a string literal!"); |
| |
| // String concat. Note that keywords like __func__ and __FUNCTION__ are not |
| // considered to be strings for concatenation purposes. |
| llvm::SmallVector<Token, 4> StringToks; |
| |
| do { |
| StringToks.push_back(Tok); |
| ConsumeStringToken(); |
| } while (isTokenStringLiteral()); |
| |
| // Pass the set of string tokens, ready for concatenation, to the actions. |
| return Actions.ActOnStringLiteral(&StringToks[0], StringToks.size()); |
| } |