Mercurial > hg > CbC > CbC_llvm
diff tools/clang/lib/Parse/ParseStmt.cpp @ 0:95c75e76d11b LLVM3.4
LLVM 3.4
author | Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp> |
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date | Thu, 12 Dec 2013 13:56:28 +0900 |
parents | |
children | e4204d083e25 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/tools/clang/lib/Parse/ParseStmt.cpp Thu Dec 12 13:56:28 2013 +0900 @@ -0,0 +1,2730 @@ +//===--- ParseStmt.cpp - Statement and Block Parser -----------------------===// +// +// 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 Statement and Block portions of the Parser +// interface. +// +//===----------------------------------------------------------------------===// + +#include "clang/Parse/Parser.h" +#include "RAIIObjectsForParser.h" +#include "clang/AST/ASTContext.h" +#include "clang/Basic/Diagnostic.h" +#include "clang/Basic/PrettyStackTrace.h" +#include "clang/Basic/SourceManager.h" +#include "clang/Basic/TargetInfo.h" +#include "clang/Sema/DeclSpec.h" +#include "clang/Sema/PrettyDeclStackTrace.h" +#include "clang/Sema/Scope.h" +#include "clang/Sema/TypoCorrection.h" +#include "llvm/MC/MCAsmInfo.h" +#include "llvm/MC/MCContext.h" +#include "llvm/MC/MCObjectFileInfo.h" +#include "llvm/MC/MCParser/MCAsmParser.h" +#include "llvm/MC/MCRegisterInfo.h" +#include "llvm/MC/MCStreamer.h" +#include "llvm/MC/MCSubtargetInfo.h" +#include "llvm/MC/MCTargetAsmParser.h" +#include "llvm/Support/SourceMgr.h" +#include "llvm/Support/TargetRegistry.h" +#include "llvm/Support/TargetSelect.h" +#include "llvm/ADT/SmallString.h" +using namespace clang; + +//===----------------------------------------------------------------------===// +// C99 6.8: Statements and Blocks. +//===----------------------------------------------------------------------===// + +/// \brief Parse a standalone statement (for instance, as the body of an 'if', +/// 'while', or 'for'). +StmtResult Parser::ParseStatement(SourceLocation *TrailingElseLoc) { + StmtResult Res; + + // We may get back a null statement if we found a #pragma. Keep going until + // we get an actual statement. + do { + StmtVector Stmts; + Res = ParseStatementOrDeclaration(Stmts, true, TrailingElseLoc); + } while (!Res.isInvalid() && !Res.get()); + + return Res; +} + +/// ParseStatementOrDeclaration - Read 'statement' or 'declaration'. +/// StatementOrDeclaration: +/// statement +/// declaration +/// +/// statement: +/// labeled-statement +/// compound-statement +/// expression-statement +/// selection-statement +/// iteration-statement +/// jump-statement +/// [C++] declaration-statement +/// [C++] try-block +/// [MS] seh-try-block +/// [OBC] objc-throw-statement +/// [OBC] objc-try-catch-statement +/// [OBC] objc-synchronized-statement +/// [GNU] asm-statement +/// [OMP] openmp-construct [TODO] +/// +/// labeled-statement: +/// identifier ':' statement +/// 'case' constant-expression ':' statement +/// 'default' ':' statement +/// +/// selection-statement: +/// if-statement +/// switch-statement +/// +/// iteration-statement: +/// while-statement +/// do-statement +/// for-statement +/// +/// expression-statement: +/// expression[opt] ';' +/// +/// jump-statement: +/// 'goto' identifier ';' +/// 'continue' ';' +/// 'break' ';' +/// 'return' expression[opt] ';' +/// [GNU] 'goto' '*' expression ';' +/// +/// [OBC] objc-throw-statement: +/// [OBC] '@' 'throw' expression ';' +/// [OBC] '@' 'throw' ';' +/// +StmtResult +Parser::ParseStatementOrDeclaration(StmtVector &Stmts, bool OnlyStatement, + SourceLocation *TrailingElseLoc) { + + ParenBraceBracketBalancer BalancerRAIIObj(*this); + + ParsedAttributesWithRange Attrs(AttrFactory); + MaybeParseCXX11Attributes(Attrs, 0, /*MightBeObjCMessageSend*/ true); + + StmtResult Res = ParseStatementOrDeclarationAfterAttributes(Stmts, + OnlyStatement, TrailingElseLoc, Attrs); + + assert((Attrs.empty() || Res.isInvalid() || Res.isUsable()) && + "attributes on empty statement"); + + if (Attrs.empty() || Res.isInvalid()) + return Res; + + return Actions.ProcessStmtAttributes(Res.get(), Attrs.getList(), Attrs.Range); +} + +namespace { +class StatementFilterCCC : public CorrectionCandidateCallback { +public: + StatementFilterCCC(Token nextTok) : NextToken(nextTok) { + WantTypeSpecifiers = nextTok.is(tok::l_paren) || nextTok.is(tok::less) || + nextTok.is(tok::identifier) || nextTok.is(tok::star) || + nextTok.is(tok::amp) || nextTok.is(tok::l_square); + WantExpressionKeywords = nextTok.is(tok::l_paren) || + nextTok.is(tok::identifier) || + nextTok.is(tok::arrow) || nextTok.is(tok::period); + WantRemainingKeywords = nextTok.is(tok::l_paren) || nextTok.is(tok::semi) || + nextTok.is(tok::identifier) || + nextTok.is(tok::l_brace); + WantCXXNamedCasts = false; + } + + virtual bool ValidateCandidate(const TypoCorrection &candidate) { + if (FieldDecl *FD = candidate.getCorrectionDeclAs<FieldDecl>()) + return !candidate.getCorrectionSpecifier() || isa<ObjCIvarDecl>(FD); + if (NextToken.is(tok::equal)) + return candidate.getCorrectionDeclAs<VarDecl>(); + if (NextToken.is(tok::period) && + candidate.getCorrectionDeclAs<NamespaceDecl>()) + return false; + return CorrectionCandidateCallback::ValidateCandidate(candidate); + } + +private: + Token NextToken; +}; +} + +StmtResult +Parser::ParseStatementOrDeclarationAfterAttributes(StmtVector &Stmts, + bool OnlyStatement, SourceLocation *TrailingElseLoc, + ParsedAttributesWithRange &Attrs) { + const char *SemiError = 0; + StmtResult Res; + + // Cases in this switch statement should fall through if the parser expects + // the token to end in a semicolon (in which case SemiError should be set), + // or they directly 'return;' if not. +Retry: + tok::TokenKind Kind = Tok.getKind(); + SourceLocation AtLoc; + switch (Kind) { + case tok::at: // May be a @try or @throw statement + { + ProhibitAttributes(Attrs); // TODO: is it correct? + AtLoc = ConsumeToken(); // consume @ + return ParseObjCAtStatement(AtLoc); + } + + case tok::code_completion: + Actions.CodeCompleteOrdinaryName(getCurScope(), Sema::PCC_Statement); + cutOffParsing(); + return StmtError(); + + case tok::identifier: { + Token Next = NextToken(); + if (Next.is(tok::colon)) { // C99 6.8.1: labeled-statement + // identifier ':' statement + return ParseLabeledStatement(Attrs); + } + + // Look up the identifier, and typo-correct it to a keyword if it's not + // found. + if (Next.isNot(tok::coloncolon)) { + // Try to limit which sets of keywords should be included in typo + // correction based on what the next token is. + StatementFilterCCC Validator(Next); + if (TryAnnotateName(/*IsAddressOfOperand*/false, &Validator) + == ANK_Error) { + // Handle errors here by skipping up to the next semicolon or '}', and + // eat the semicolon if that's what stopped us. + SkipUntil(tok::r_brace, StopAtSemi | StopBeforeMatch); + if (Tok.is(tok::semi)) + ConsumeToken(); + return StmtError(); + } + + // If the identifier was typo-corrected, try again. + if (Tok.isNot(tok::identifier)) + goto Retry; + } + + // Fall through + } + + default: { + if ((getLangOpts().CPlusPlus || !OnlyStatement) && isDeclarationStatement()) { + SourceLocation DeclStart = Tok.getLocation(), DeclEnd; + DeclGroupPtrTy Decl = ParseDeclaration(Stmts, Declarator::BlockContext, + DeclEnd, Attrs); + return Actions.ActOnDeclStmt(Decl, DeclStart, DeclEnd); + } + + if (Tok.is(tok::r_brace)) { + Diag(Tok, diag::err_expected_statement); + return StmtError(); + } + + return ParseExprStatement(); + } + + case tok::kw_case: // C99 6.8.1: labeled-statement + return ParseCaseStatement(); + case tok::kw_default: // C99 6.8.1: labeled-statement + return ParseDefaultStatement(); + + case tok::l_brace: // C99 6.8.2: compound-statement + return ParseCompoundStatement(); + case tok::semi: { // C99 6.8.3p3: expression[opt] ';' + bool HasLeadingEmptyMacro = Tok.hasLeadingEmptyMacro(); + return Actions.ActOnNullStmt(ConsumeToken(), HasLeadingEmptyMacro); + } + + case tok::kw_if: // C99 6.8.4.1: if-statement + return ParseIfStatement(TrailingElseLoc); + case tok::kw_switch: // C99 6.8.4.2: switch-statement + return ParseSwitchStatement(TrailingElseLoc); + + case tok::kw_while: // C99 6.8.5.1: while-statement + return ParseWhileStatement(TrailingElseLoc); + case tok::kw_do: // C99 6.8.5.2: do-statement + Res = ParseDoStatement(); + SemiError = "do/while"; + break; + case tok::kw_for: // C99 6.8.5.3: for-statement + return ParseForStatement(TrailingElseLoc); + + case tok::kw_goto: // C99 6.8.6.1: goto-statement + Res = ParseGotoStatement(); + SemiError = "goto"; + break; + case tok::kw_continue: // C99 6.8.6.2: continue-statement + Res = ParseContinueStatement(); + SemiError = "continue"; + break; + case tok::kw_break: // C99 6.8.6.3: break-statement + Res = ParseBreakStatement(); + SemiError = "break"; + break; + case tok::kw_return: // C99 6.8.6.4: return-statement + Res = ParseReturnStatement(); + SemiError = "return"; + break; + + case tok::kw_asm: { + ProhibitAttributes(Attrs); + bool msAsm = false; + Res = ParseAsmStatement(msAsm); + Res = Actions.ActOnFinishFullStmt(Res.get()); + if (msAsm) return Res; + SemiError = "asm"; + break; + } + + case tok::kw_try: // C++ 15: try-block + return ParseCXXTryBlock(); + + case tok::kw___try: + ProhibitAttributes(Attrs); // TODO: is it correct? + return ParseSEHTryBlock(); + + case tok::annot_pragma_vis: + ProhibitAttributes(Attrs); + HandlePragmaVisibility(); + return StmtEmpty(); + + case tok::annot_pragma_pack: + ProhibitAttributes(Attrs); + HandlePragmaPack(); + return StmtEmpty(); + + case tok::annot_pragma_msstruct: + ProhibitAttributes(Attrs); + HandlePragmaMSStruct(); + return StmtEmpty(); + + case tok::annot_pragma_align: + ProhibitAttributes(Attrs); + HandlePragmaAlign(); + return StmtEmpty(); + + case tok::annot_pragma_weak: + ProhibitAttributes(Attrs); + HandlePragmaWeak(); + return StmtEmpty(); + + case tok::annot_pragma_weakalias: + ProhibitAttributes(Attrs); + HandlePragmaWeakAlias(); + return StmtEmpty(); + + case tok::annot_pragma_redefine_extname: + ProhibitAttributes(Attrs); + HandlePragmaRedefineExtname(); + return StmtEmpty(); + + case tok::annot_pragma_fp_contract: + ProhibitAttributes(Attrs); + Diag(Tok, diag::err_pragma_fp_contract_scope); + ConsumeToken(); + return StmtError(); + + case tok::annot_pragma_opencl_extension: + ProhibitAttributes(Attrs); + HandlePragmaOpenCLExtension(); + return StmtEmpty(); + + case tok::annot_pragma_captured: + ProhibitAttributes(Attrs); + return HandlePragmaCaptured(); + + case tok::annot_pragma_openmp: + ProhibitAttributes(Attrs); + return ParseOpenMPDeclarativeOrExecutableDirective(); + + } + + // If we reached this code, the statement must end in a semicolon. + if (Tok.is(tok::semi)) { + ConsumeToken(); + } else if (!Res.isInvalid()) { + // If the result was valid, then we do want to diagnose this. Use + // ExpectAndConsume to emit the diagnostic, even though we know it won't + // succeed. + ExpectAndConsume(tok::semi, diag::err_expected_semi_after_stmt, SemiError); + // Skip until we see a } or ;, but don't eat it. + SkipUntil(tok::r_brace, StopAtSemi | StopBeforeMatch); + } + + return Res; +} + +/// \brief Parse an expression statement. +StmtResult Parser::ParseExprStatement() { + // If a case keyword is missing, this is where it should be inserted. + Token OldToken = Tok; + + // expression[opt] ';' + ExprResult Expr(ParseExpression()); + if (Expr.isInvalid()) { + // If the expression is invalid, skip ahead to the next semicolon or '}'. + // Not doing this opens us up to the possibility of infinite loops if + // ParseExpression does not consume any tokens. + SkipUntil(tok::r_brace, StopAtSemi | StopBeforeMatch); + if (Tok.is(tok::semi)) + ConsumeToken(); + return Actions.ActOnExprStmtError(); + } + + if (Tok.is(tok::colon) && getCurScope()->isSwitchScope() && + Actions.CheckCaseExpression(Expr.get())) { + // If a constant expression is followed by a colon inside a switch block, + // suggest a missing case keyword. + Diag(OldToken, diag::err_expected_case_before_expression) + << FixItHint::CreateInsertion(OldToken.getLocation(), "case "); + + // Recover parsing as a case statement. + return ParseCaseStatement(/*MissingCase=*/true, Expr); + } + + // Otherwise, eat the semicolon. + ExpectAndConsumeSemi(diag::err_expected_semi_after_expr); + return Actions.ActOnExprStmt(Expr); +} + +StmtResult Parser::ParseSEHTryBlock() { + assert(Tok.is(tok::kw___try) && "Expected '__try'"); + SourceLocation Loc = ConsumeToken(); + return ParseSEHTryBlockCommon(Loc); +} + +/// ParseSEHTryBlockCommon +/// +/// seh-try-block: +/// '__try' compound-statement seh-handler +/// +/// seh-handler: +/// seh-except-block +/// seh-finally-block +/// +StmtResult Parser::ParseSEHTryBlockCommon(SourceLocation TryLoc) { + if(Tok.isNot(tok::l_brace)) + return StmtError(Diag(Tok,diag::err_expected_lbrace)); + + StmtResult TryBlock(ParseCompoundStatement()); + if(TryBlock.isInvalid()) + return TryBlock; + + StmtResult Handler; + if (Tok.is(tok::identifier) && + Tok.getIdentifierInfo() == getSEHExceptKeyword()) { + SourceLocation Loc = ConsumeToken(); + Handler = ParseSEHExceptBlock(Loc); + } else if (Tok.is(tok::kw___finally)) { + SourceLocation Loc = ConsumeToken(); + Handler = ParseSEHFinallyBlock(Loc); + } else { + return StmtError(Diag(Tok,diag::err_seh_expected_handler)); + } + + if(Handler.isInvalid()) + return Handler; + + return Actions.ActOnSEHTryBlock(false /* IsCXXTry */, + TryLoc, + TryBlock.take(), + Handler.take()); +} + +/// ParseSEHExceptBlock - Handle __except +/// +/// seh-except-block: +/// '__except' '(' seh-filter-expression ')' compound-statement +/// +StmtResult Parser::ParseSEHExceptBlock(SourceLocation ExceptLoc) { + PoisonIdentifierRAIIObject raii(Ident__exception_code, false), + raii2(Ident___exception_code, false), + raii3(Ident_GetExceptionCode, false); + + if(ExpectAndConsume(tok::l_paren,diag::err_expected_lparen)) + return StmtError(); + + ParseScope ExpectScope(this, Scope::DeclScope | Scope::ControlScope); + + if (getLangOpts().Borland) { + Ident__exception_info->setIsPoisoned(false); + Ident___exception_info->setIsPoisoned(false); + Ident_GetExceptionInfo->setIsPoisoned(false); + } + ExprResult FilterExpr(ParseExpression()); + + if (getLangOpts().Borland) { + Ident__exception_info->setIsPoisoned(true); + Ident___exception_info->setIsPoisoned(true); + Ident_GetExceptionInfo->setIsPoisoned(true); + } + + if(FilterExpr.isInvalid()) + return StmtError(); + + if(ExpectAndConsume(tok::r_paren,diag::err_expected_rparen)) + return StmtError(); + + StmtResult Block(ParseCompoundStatement()); + + if(Block.isInvalid()) + return Block; + + return Actions.ActOnSEHExceptBlock(ExceptLoc, FilterExpr.take(), Block.take()); +} + +/// ParseSEHFinallyBlock - Handle __finally +/// +/// seh-finally-block: +/// '__finally' compound-statement +/// +StmtResult Parser::ParseSEHFinallyBlock(SourceLocation FinallyBlock) { + PoisonIdentifierRAIIObject raii(Ident__abnormal_termination, false), + raii2(Ident___abnormal_termination, false), + raii3(Ident_AbnormalTermination, false); + + StmtResult Block(ParseCompoundStatement()); + if(Block.isInvalid()) + return Block; + + return Actions.ActOnSEHFinallyBlock(FinallyBlock,Block.take()); +} + +/// ParseLabeledStatement - We have an identifier and a ':' after it. +/// +/// labeled-statement: +/// identifier ':' statement +/// [GNU] identifier ':' attributes[opt] statement +/// +StmtResult Parser::ParseLabeledStatement(ParsedAttributesWithRange &attrs) { + assert(Tok.is(tok::identifier) && Tok.getIdentifierInfo() && + "Not an identifier!"); + + Token IdentTok = Tok; // Save the whole token. + ConsumeToken(); // eat the identifier. + + assert(Tok.is(tok::colon) && "Not a label!"); + + // identifier ':' statement + SourceLocation ColonLoc = ConsumeToken(); + + // Read label attributes, if present. + StmtResult SubStmt; + if (Tok.is(tok::kw___attribute)) { + ParsedAttributesWithRange TempAttrs(AttrFactory); + ParseGNUAttributes(TempAttrs); + + // In C++, GNU attributes only apply to the label if they are followed by a + // semicolon, to disambiguate label attributes from attributes on a labeled + // declaration. + // + // This doesn't quite match what GCC does; if the attribute list is empty + // and followed by a semicolon, GCC will reject (it appears to parse the + // attributes as part of a statement in that case). That looks like a bug. + if (!getLangOpts().CPlusPlus || Tok.is(tok::semi)) + attrs.takeAllFrom(TempAttrs); + else if (isDeclarationStatement()) { + StmtVector Stmts; + // FIXME: We should do this whether or not we have a declaration + // statement, but that doesn't work correctly (because ProhibitAttributes + // can't handle GNU attributes), so only call it in the one case where + // GNU attributes are allowed. + SubStmt = ParseStatementOrDeclarationAfterAttributes( + Stmts, /*OnlyStmts*/ true, 0, TempAttrs); + if (!TempAttrs.empty() && !SubStmt.isInvalid()) + SubStmt = Actions.ProcessStmtAttributes( + SubStmt.get(), TempAttrs.getList(), TempAttrs.Range); + } else { + Diag(Tok, diag::err_expected_semi_after) << "__attribute__"; + } + } + + // If we've not parsed a statement yet, parse one now. + if (!SubStmt.isInvalid() && !SubStmt.isUsable()) + SubStmt = ParseStatement(); + + // Broken substmt shouldn't prevent the label from being added to the AST. + if (SubStmt.isInvalid()) + SubStmt = Actions.ActOnNullStmt(ColonLoc); + + LabelDecl *LD = Actions.LookupOrCreateLabel(IdentTok.getIdentifierInfo(), + IdentTok.getLocation()); + if (AttributeList *Attrs = attrs.getList()) { + Actions.ProcessDeclAttributeList(Actions.CurScope, LD, Attrs); + attrs.clear(); + } + + return Actions.ActOnLabelStmt(IdentTok.getLocation(), LD, ColonLoc, + SubStmt.get()); +} + +/// ParseCaseStatement +/// labeled-statement: +/// 'case' constant-expression ':' statement +/// [GNU] 'case' constant-expression '...' constant-expression ':' statement +/// +StmtResult Parser::ParseCaseStatement(bool MissingCase, ExprResult Expr) { + assert((MissingCase || Tok.is(tok::kw_case)) && "Not a case stmt!"); + + // It is very very common for code to contain many case statements recursively + // nested, as in (but usually without indentation): + // case 1: + // case 2: + // case 3: + // case 4: + // case 5: etc. + // + // Parsing this naively works, but is both inefficient and can cause us to run + // out of stack space in our recursive descent parser. As a special case, + // flatten this recursion into an iterative loop. This is complex and gross, + // but all the grossness is constrained to ParseCaseStatement (and some + // weirdness in the actions), so this is just local grossness :). + + // TopLevelCase - This is the highest level we have parsed. 'case 1' in the + // example above. + StmtResult TopLevelCase(true); + + // DeepestParsedCaseStmt - This is the deepest statement we have parsed, which + // gets updated each time a new case is parsed, and whose body is unset so + // far. When parsing 'case 4', this is the 'case 3' node. + Stmt *DeepestParsedCaseStmt = 0; + + // While we have case statements, eat and stack them. + SourceLocation ColonLoc; + do { + SourceLocation CaseLoc = MissingCase ? Expr.get()->getExprLoc() : + ConsumeToken(); // eat the 'case'. + + if (Tok.is(tok::code_completion)) { + Actions.CodeCompleteCase(getCurScope()); + cutOffParsing(); + return StmtError(); + } + + /// We don't want to treat 'case x : y' as a potential typo for 'case x::y'. + /// Disable this form of error recovery while we're parsing the case + /// expression. + ColonProtectionRAIIObject ColonProtection(*this); + + ExprResult LHS(MissingCase ? Expr : ParseConstantExpression()); + MissingCase = false; + if (LHS.isInvalid()) { + SkipUntil(tok::colon, StopAtSemi); + return StmtError(); + } + + // GNU case range extension. + SourceLocation DotDotDotLoc; + ExprResult RHS; + if (Tok.is(tok::ellipsis)) { + Diag(Tok, diag::ext_gnu_case_range); + DotDotDotLoc = ConsumeToken(); + + RHS = ParseConstantExpression(); + if (RHS.isInvalid()) { + SkipUntil(tok::colon, StopAtSemi); + return StmtError(); + } + } + + ColonProtection.restore(); + + if (Tok.is(tok::colon)) { + ColonLoc = ConsumeToken(); + + // Treat "case blah;" as a typo for "case blah:". + } else if (Tok.is(tok::semi)) { + ColonLoc = ConsumeToken(); + Diag(ColonLoc, diag::err_expected_colon_after) << "'case'" + << FixItHint::CreateReplacement(ColonLoc, ":"); + } else { + SourceLocation ExpectedLoc = PP.getLocForEndOfToken(PrevTokLocation); + Diag(ExpectedLoc, diag::err_expected_colon_after) << "'case'" + << FixItHint::CreateInsertion(ExpectedLoc, ":"); + ColonLoc = ExpectedLoc; + } + + StmtResult Case = + Actions.ActOnCaseStmt(CaseLoc, LHS.get(), DotDotDotLoc, + RHS.get(), ColonLoc); + + // If we had a sema error parsing this case, then just ignore it and + // continue parsing the sub-stmt. + if (Case.isInvalid()) { + if (TopLevelCase.isInvalid()) // No parsed case stmts. + return ParseStatement(); + // Otherwise, just don't add it as a nested case. + } else { + // If this is the first case statement we parsed, it becomes TopLevelCase. + // Otherwise we link it into the current chain. + Stmt *NextDeepest = Case.get(); + if (TopLevelCase.isInvalid()) + TopLevelCase = Case; + else + Actions.ActOnCaseStmtBody(DeepestParsedCaseStmt, Case.get()); + DeepestParsedCaseStmt = NextDeepest; + } + + // Handle all case statements. + } while (Tok.is(tok::kw_case)); + + assert(!TopLevelCase.isInvalid() && "Should have parsed at least one case!"); + + // If we found a non-case statement, start by parsing it. + StmtResult SubStmt; + + if (Tok.isNot(tok::r_brace)) { + SubStmt = ParseStatement(); + } else { + // Nicely diagnose the common error "switch (X) { case 4: }", which is + // not valid. + SourceLocation AfterColonLoc = PP.getLocForEndOfToken(ColonLoc); + Diag(AfterColonLoc, diag::err_label_end_of_compound_statement) + << FixItHint::CreateInsertion(AfterColonLoc, " ;"); + SubStmt = true; + } + + // Broken sub-stmt shouldn't prevent forming the case statement properly. + if (SubStmt.isInvalid()) + SubStmt = Actions.ActOnNullStmt(SourceLocation()); + + // Install the body into the most deeply-nested case. + Actions.ActOnCaseStmtBody(DeepestParsedCaseStmt, SubStmt.get()); + + // Return the top level parsed statement tree. + return TopLevelCase; +} + +/// ParseDefaultStatement +/// labeled-statement: +/// 'default' ':' statement +/// Note that this does not parse the 'statement' at the end. +/// +StmtResult Parser::ParseDefaultStatement() { + assert(Tok.is(tok::kw_default) && "Not a default stmt!"); + SourceLocation DefaultLoc = ConsumeToken(); // eat the 'default'. + + SourceLocation ColonLoc; + if (Tok.is(tok::colon)) { + ColonLoc = ConsumeToken(); + + // Treat "default;" as a typo for "default:". + } else if (Tok.is(tok::semi)) { + ColonLoc = ConsumeToken(); + Diag(ColonLoc, diag::err_expected_colon_after) << "'default'" + << FixItHint::CreateReplacement(ColonLoc, ":"); + } else { + SourceLocation ExpectedLoc = PP.getLocForEndOfToken(PrevTokLocation); + Diag(ExpectedLoc, diag::err_expected_colon_after) << "'default'" + << FixItHint::CreateInsertion(ExpectedLoc, ":"); + ColonLoc = ExpectedLoc; + } + + StmtResult SubStmt; + + if (Tok.isNot(tok::r_brace)) { + SubStmt = ParseStatement(); + } else { + // Diagnose the common error "switch (X) {... default: }", which is + // not valid. + SourceLocation AfterColonLoc = PP.getLocForEndOfToken(ColonLoc); + Diag(AfterColonLoc, diag::err_label_end_of_compound_statement) + << FixItHint::CreateInsertion(AfterColonLoc, " ;"); + SubStmt = true; + } + + // Broken sub-stmt shouldn't prevent forming the case statement properly. + if (SubStmt.isInvalid()) + SubStmt = Actions.ActOnNullStmt(ColonLoc); + + return Actions.ActOnDefaultStmt(DefaultLoc, ColonLoc, + SubStmt.get(), getCurScope()); +} + +StmtResult Parser::ParseCompoundStatement(bool isStmtExpr) { + return ParseCompoundStatement(isStmtExpr, Scope::DeclScope); +} + +/// ParseCompoundStatement - Parse a "{}" block. +/// +/// compound-statement: [C99 6.8.2] +/// { block-item-list[opt] } +/// [GNU] { label-declarations block-item-list } [TODO] +/// +/// block-item-list: +/// block-item +/// block-item-list block-item +/// +/// block-item: +/// declaration +/// [GNU] '__extension__' declaration +/// statement +/// [OMP] openmp-directive [TODO] +/// +/// [GNU] label-declarations: +/// [GNU] label-declaration +/// [GNU] label-declarations label-declaration +/// +/// [GNU] label-declaration: +/// [GNU] '__label__' identifier-list ';' +/// +/// [OMP] openmp-directive: [TODO] +/// [OMP] barrier-directive +/// [OMP] flush-directive +/// +StmtResult Parser::ParseCompoundStatement(bool isStmtExpr, + unsigned ScopeFlags) { + assert(Tok.is(tok::l_brace) && "Not a compount stmt!"); + + // Enter a scope to hold everything within the compound stmt. Compound + // statements can always hold declarations. + ParseScope CompoundScope(this, ScopeFlags); + + // Parse the statements in the body. + return ParseCompoundStatementBody(isStmtExpr); +} + +/// Parse any pragmas at the start of the compound expression. We handle these +/// separately since some pragmas (FP_CONTRACT) must appear before any C +/// statement in the compound, but may be intermingled with other pragmas. +void Parser::ParseCompoundStatementLeadingPragmas() { + bool checkForPragmas = true; + while (checkForPragmas) { + switch (Tok.getKind()) { + case tok::annot_pragma_vis: + HandlePragmaVisibility(); + break; + case tok::annot_pragma_pack: + HandlePragmaPack(); + break; + case tok::annot_pragma_msstruct: + HandlePragmaMSStruct(); + break; + case tok::annot_pragma_align: + HandlePragmaAlign(); + break; + case tok::annot_pragma_weak: + HandlePragmaWeak(); + break; + case tok::annot_pragma_weakalias: + HandlePragmaWeakAlias(); + break; + case tok::annot_pragma_redefine_extname: + HandlePragmaRedefineExtname(); + break; + case tok::annot_pragma_opencl_extension: + HandlePragmaOpenCLExtension(); + break; + case tok::annot_pragma_fp_contract: + HandlePragmaFPContract(); + break; + default: + checkForPragmas = false; + break; + } + } + +} + +/// ParseCompoundStatementBody - Parse a sequence of statements and invoke the +/// ActOnCompoundStmt action. This expects the '{' to be the current token, and +/// consume the '}' at the end of the block. It does not manipulate the scope +/// stack. +StmtResult Parser::ParseCompoundStatementBody(bool isStmtExpr) { + PrettyStackTraceLoc CrashInfo(PP.getSourceManager(), + Tok.getLocation(), + "in compound statement ('{}')"); + + // Record the state of the FP_CONTRACT pragma, restore on leaving the + // compound statement. + Sema::FPContractStateRAII SaveFPContractState(Actions); + + InMessageExpressionRAIIObject InMessage(*this, false); + BalancedDelimiterTracker T(*this, tok::l_brace); + if (T.consumeOpen()) + return StmtError(); + + Sema::CompoundScopeRAII CompoundScope(Actions); + + // Parse any pragmas at the beginning of the compound statement. + ParseCompoundStatementLeadingPragmas(); + + StmtVector Stmts; + + // "__label__ X, Y, Z;" is the GNU "Local Label" extension. These are + // only allowed at the start of a compound stmt regardless of the language. + while (Tok.is(tok::kw___label__)) { + SourceLocation LabelLoc = ConsumeToken(); + + SmallVector<Decl *, 8> DeclsInGroup; + while (1) { + if (Tok.isNot(tok::identifier)) { + Diag(Tok, diag::err_expected_ident); + break; + } + + IdentifierInfo *II = Tok.getIdentifierInfo(); + SourceLocation IdLoc = ConsumeToken(); + DeclsInGroup.push_back(Actions.LookupOrCreateLabel(II, IdLoc, LabelLoc)); + + if (!Tok.is(tok::comma)) + break; + ConsumeToken(); + } + + DeclSpec DS(AttrFactory); + DeclGroupPtrTy Res = + Actions.FinalizeDeclaratorGroup(getCurScope(), DS, DeclsInGroup); + StmtResult R = Actions.ActOnDeclStmt(Res, LabelLoc, Tok.getLocation()); + + ExpectAndConsumeSemi(diag::err_expected_semi_declaration); + if (R.isUsable()) + Stmts.push_back(R.release()); + } + + while (Tok.isNot(tok::r_brace) && Tok.isNot(tok::eof)) { + if (Tok.is(tok::annot_pragma_unused)) { + HandlePragmaUnused(); + continue; + } + + if (getLangOpts().MicrosoftExt && (Tok.is(tok::kw___if_exists) || + Tok.is(tok::kw___if_not_exists))) { + ParseMicrosoftIfExistsStatement(Stmts); + continue; + } + + StmtResult R; + if (Tok.isNot(tok::kw___extension__)) { + R = ParseStatementOrDeclaration(Stmts, false); + } else { + // __extension__ can start declarations and it can also be a unary + // operator for expressions. Consume multiple __extension__ markers here + // until we can determine which is which. + // FIXME: This loses extension expressions in the AST! + SourceLocation ExtLoc = ConsumeToken(); + while (Tok.is(tok::kw___extension__)) + ConsumeToken(); + + ParsedAttributesWithRange attrs(AttrFactory); + MaybeParseCXX11Attributes(attrs, 0, /*MightBeObjCMessageSend*/ true); + + // If this is the start of a declaration, parse it as such. + if (isDeclarationStatement()) { + // __extension__ silences extension warnings in the subdeclaration. + // FIXME: Save the __extension__ on the decl as a node somehow? + ExtensionRAIIObject O(Diags); + + SourceLocation DeclStart = Tok.getLocation(), DeclEnd; + DeclGroupPtrTy Res = ParseDeclaration(Stmts, + Declarator::BlockContext, DeclEnd, + attrs); + R = Actions.ActOnDeclStmt(Res, DeclStart, DeclEnd); + } else { + // Otherwise this was a unary __extension__ marker. + ExprResult Res(ParseExpressionWithLeadingExtension(ExtLoc)); + + if (Res.isInvalid()) { + SkipUntil(tok::semi); + continue; + } + + // FIXME: Use attributes? + // Eat the semicolon at the end of stmt and convert the expr into a + // statement. + ExpectAndConsumeSemi(diag::err_expected_semi_after_expr); + R = Actions.ActOnExprStmt(Res); + } + } + + if (R.isUsable()) + Stmts.push_back(R.release()); + } + + SourceLocation CloseLoc = Tok.getLocation(); + + // We broke out of the while loop because we found a '}' or EOF. + if (!T.consumeClose()) + // Recover by creating a compound statement with what we parsed so far, + // instead of dropping everything and returning StmtError(); + CloseLoc = T.getCloseLocation(); + + return Actions.ActOnCompoundStmt(T.getOpenLocation(), CloseLoc, + Stmts, isStmtExpr); +} + +/// ParseParenExprOrCondition: +/// [C ] '(' expression ')' +/// [C++] '(' condition ')' [not allowed if OnlyAllowCondition=true] +/// +/// This function parses and performs error recovery on the specified condition +/// or expression (depending on whether we're in C++ or C mode). This function +/// goes out of its way to recover well. It returns true if there was a parser +/// error (the right paren couldn't be found), which indicates that the caller +/// should try to recover harder. It returns false if the condition is +/// successfully parsed. Note that a successful parse can still have semantic +/// errors in the condition. +bool Parser::ParseParenExprOrCondition(ExprResult &ExprResult, + Decl *&DeclResult, + SourceLocation Loc, + bool ConvertToBoolean) { + BalancedDelimiterTracker T(*this, tok::l_paren); + T.consumeOpen(); + + if (getLangOpts().CPlusPlus) + ParseCXXCondition(ExprResult, DeclResult, Loc, ConvertToBoolean); + else { + ExprResult = ParseExpression(); + DeclResult = 0; + + // If required, convert to a boolean value. + if (!ExprResult.isInvalid() && ConvertToBoolean) + ExprResult + = Actions.ActOnBooleanCondition(getCurScope(), Loc, ExprResult.get()); + } + + // If the parser was confused by the condition and we don't have a ')', try to + // recover by skipping ahead to a semi and bailing out. If condexp is + // semantically invalid but we have well formed code, keep going. + if (ExprResult.isInvalid() && !DeclResult && Tok.isNot(tok::r_paren)) { + SkipUntil(tok::semi); + // Skipping may have stopped if it found the containing ')'. If so, we can + // continue parsing the if statement. + if (Tok.isNot(tok::r_paren)) + return true; + } + + // Otherwise the condition is valid or the rparen is present. + T.consumeClose(); + + // Check for extraneous ')'s to catch things like "if (foo())) {". We know + // that all callers are looking for a statement after the condition, so ")" + // isn't valid. + while (Tok.is(tok::r_paren)) { + Diag(Tok, diag::err_extraneous_rparen_in_condition) + << FixItHint::CreateRemoval(Tok.getLocation()); + ConsumeParen(); + } + + return false; +} + + +/// ParseIfStatement +/// if-statement: [C99 6.8.4.1] +/// 'if' '(' expression ')' statement +/// 'if' '(' expression ')' statement 'else' statement +/// [C++] 'if' '(' condition ')' statement +/// [C++] 'if' '(' condition ')' statement 'else' statement +/// +StmtResult Parser::ParseIfStatement(SourceLocation *TrailingElseLoc) { + assert(Tok.is(tok::kw_if) && "Not an if stmt!"); + SourceLocation IfLoc = ConsumeToken(); // eat the 'if'. + + if (Tok.isNot(tok::l_paren)) { + Diag(Tok, diag::err_expected_lparen_after) << "if"; + SkipUntil(tok::semi); + return StmtError(); + } + + bool C99orCXX = getLangOpts().C99 || getLangOpts().CPlusPlus; + + // C99 6.8.4p3 - In C99, the if statement is a block. This is not + // the case for C90. + // + // C++ 6.4p3: + // A name introduced by a declaration in a condition is in scope from its + // point of declaration until the end of the substatements controlled by the + // condition. + // C++ 3.3.2p4: + // Names declared in the for-init-statement, and in the condition of if, + // while, for, and switch statements are local to the if, while, for, or + // switch statement (including the controlled statement). + // + ParseScope IfScope(this, Scope::DeclScope | Scope::ControlScope, C99orCXX); + + // Parse the condition. + ExprResult CondExp; + Decl *CondVar = 0; + if (ParseParenExprOrCondition(CondExp, CondVar, IfLoc, true)) + return StmtError(); + + FullExprArg FullCondExp(Actions.MakeFullExpr(CondExp.get(), IfLoc)); + + // C99 6.8.4p3 - In C99, the body of the if statement is a scope, even if + // there is no compound stmt. C90 does not have this clause. We only do this + // if the body isn't a compound statement to avoid push/pop in common cases. + // + // C++ 6.4p1: + // The substatement in a selection-statement (each substatement, in the else + // form of the if statement) implicitly defines a local scope. + // + // For C++ we create a scope for the condition and a new scope for + // substatements because: + // -When the 'then' scope exits, we want the condition declaration to still be + // active for the 'else' scope too. + // -Sema will detect name clashes by considering declarations of a + // 'ControlScope' as part of its direct subscope. + // -If we wanted the condition and substatement to be in the same scope, we + // would have to notify ParseStatement not to create a new scope. It's + // simpler to let it create a new scope. + // + ParseScope InnerScope(this, Scope::DeclScope, + C99orCXX && Tok.isNot(tok::l_brace)); + + // Read the 'then' stmt. + SourceLocation ThenStmtLoc = Tok.getLocation(); + + SourceLocation InnerStatementTrailingElseLoc; + StmtResult ThenStmt(ParseStatement(&InnerStatementTrailingElseLoc)); + + // Pop the 'if' scope if needed. + InnerScope.Exit(); + + // If it has an else, parse it. + SourceLocation ElseLoc; + SourceLocation ElseStmtLoc; + StmtResult ElseStmt; + + if (Tok.is(tok::kw_else)) { + if (TrailingElseLoc) + *TrailingElseLoc = Tok.getLocation(); + + ElseLoc = ConsumeToken(); + ElseStmtLoc = Tok.getLocation(); + + // C99 6.8.4p3 - In C99, the body of the if statement is a scope, even if + // there is no compound stmt. C90 does not have this clause. We only do + // this if the body isn't a compound statement to avoid push/pop in common + // cases. + // + // C++ 6.4p1: + // The substatement in a selection-statement (each substatement, in the else + // form of the if statement) implicitly defines a local scope. + // + ParseScope InnerScope(this, Scope::DeclScope, + C99orCXX && Tok.isNot(tok::l_brace)); + + ElseStmt = ParseStatement(); + + // Pop the 'else' scope if needed. + InnerScope.Exit(); + } else if (Tok.is(tok::code_completion)) { + Actions.CodeCompleteAfterIf(getCurScope()); + cutOffParsing(); + return StmtError(); + } else if (InnerStatementTrailingElseLoc.isValid()) { + Diag(InnerStatementTrailingElseLoc, diag::warn_dangling_else); + } + + IfScope.Exit(); + + // If the then or else stmt is invalid and the other is valid (and present), + // make turn the invalid one into a null stmt to avoid dropping the other + // part. If both are invalid, return error. + if ((ThenStmt.isInvalid() && ElseStmt.isInvalid()) || + (ThenStmt.isInvalid() && ElseStmt.get() == 0) || + (ThenStmt.get() == 0 && ElseStmt.isInvalid())) { + // Both invalid, or one is invalid and other is non-present: return error. + return StmtError(); + } + + // Now if either are invalid, replace with a ';'. + if (ThenStmt.isInvalid()) + ThenStmt = Actions.ActOnNullStmt(ThenStmtLoc); + if (ElseStmt.isInvalid()) + ElseStmt = Actions.ActOnNullStmt(ElseStmtLoc); + + return Actions.ActOnIfStmt(IfLoc, FullCondExp, CondVar, ThenStmt.get(), + ElseLoc, ElseStmt.get()); +} + +/// ParseSwitchStatement +/// switch-statement: +/// 'switch' '(' expression ')' statement +/// [C++] 'switch' '(' condition ')' statement +StmtResult Parser::ParseSwitchStatement(SourceLocation *TrailingElseLoc) { + assert(Tok.is(tok::kw_switch) && "Not a switch stmt!"); + SourceLocation SwitchLoc = ConsumeToken(); // eat the 'switch'. + + if (Tok.isNot(tok::l_paren)) { + Diag(Tok, diag::err_expected_lparen_after) << "switch"; + SkipUntil(tok::semi); + return StmtError(); + } + + bool C99orCXX = getLangOpts().C99 || getLangOpts().CPlusPlus; + + // C99 6.8.4p3 - In C99, the switch statement is a block. This is + // not the case for C90. Start the switch scope. + // + // C++ 6.4p3: + // A name introduced by a declaration in a condition is in scope from its + // point of declaration until the end of the substatements controlled by the + // condition. + // C++ 3.3.2p4: + // Names declared in the for-init-statement, and in the condition of if, + // while, for, and switch statements are local to the if, while, for, or + // switch statement (including the controlled statement). + // + unsigned ScopeFlags = Scope::BreakScope | Scope::SwitchScope; + if (C99orCXX) + ScopeFlags |= Scope::DeclScope | Scope::ControlScope; + ParseScope SwitchScope(this, ScopeFlags); + + // Parse the condition. + ExprResult Cond; + Decl *CondVar = 0; + if (ParseParenExprOrCondition(Cond, CondVar, SwitchLoc, false)) + return StmtError(); + + StmtResult Switch + = Actions.ActOnStartOfSwitchStmt(SwitchLoc, Cond.get(), CondVar); + + if (Switch.isInvalid()) { + // Skip the switch body. + // FIXME: This is not optimal recovery, but parsing the body is more + // dangerous due to the presence of case and default statements, which + // will have no place to connect back with the switch. + if (Tok.is(tok::l_brace)) { + ConsumeBrace(); + SkipUntil(tok::r_brace); + } else + SkipUntil(tok::semi); + return Switch; + } + + // C99 6.8.4p3 - In C99, the body of the switch statement is a scope, even if + // there is no compound stmt. C90 does not have this clause. We only do this + // if the body isn't a compound statement to avoid push/pop in common cases. + // + // C++ 6.4p1: + // The substatement in a selection-statement (each substatement, in the else + // form of the if statement) implicitly defines a local scope. + // + // See comments in ParseIfStatement for why we create a scope for the + // condition and a new scope for substatement in C++. + // + ParseScope InnerScope(this, Scope::DeclScope, + C99orCXX && Tok.isNot(tok::l_brace)); + + // Read the body statement. + StmtResult Body(ParseStatement(TrailingElseLoc)); + + // Pop the scopes. + InnerScope.Exit(); + SwitchScope.Exit(); + + if (Body.isInvalid()) { + // FIXME: Remove the case statement list from the Switch statement. + + // Put the synthesized null statement on the same line as the end of switch + // condition. + SourceLocation SynthesizedNullStmtLocation = Cond.get()->getLocEnd(); + Body = Actions.ActOnNullStmt(SynthesizedNullStmtLocation); + } + + return Actions.ActOnFinishSwitchStmt(SwitchLoc, Switch.get(), Body.get()); +} + +/// ParseWhileStatement +/// while-statement: [C99 6.8.5.1] +/// 'while' '(' expression ')' statement +/// [C++] 'while' '(' condition ')' statement +StmtResult Parser::ParseWhileStatement(SourceLocation *TrailingElseLoc) { + assert(Tok.is(tok::kw_while) && "Not a while stmt!"); + SourceLocation WhileLoc = Tok.getLocation(); + ConsumeToken(); // eat the 'while'. + + if (Tok.isNot(tok::l_paren)) { + Diag(Tok, diag::err_expected_lparen_after) << "while"; + SkipUntil(tok::semi); + return StmtError(); + } + + bool C99orCXX = getLangOpts().C99 || getLangOpts().CPlusPlus; + + // C99 6.8.5p5 - In C99, the while statement is a block. This is not + // the case for C90. Start the loop scope. + // + // C++ 6.4p3: + // A name introduced by a declaration in a condition is in scope from its + // point of declaration until the end of the substatements controlled by the + // condition. + // C++ 3.3.2p4: + // Names declared in the for-init-statement, and in the condition of if, + // while, for, and switch statements are local to the if, while, for, or + // switch statement (including the controlled statement). + // + unsigned ScopeFlags; + if (C99orCXX) + ScopeFlags = Scope::BreakScope | Scope::ContinueScope | + Scope::DeclScope | Scope::ControlScope; + else + ScopeFlags = Scope::BreakScope | Scope::ContinueScope; + ParseScope WhileScope(this, ScopeFlags); + + // Parse the condition. + ExprResult Cond; + Decl *CondVar = 0; + if (ParseParenExprOrCondition(Cond, CondVar, WhileLoc, true)) + return StmtError(); + + FullExprArg FullCond(Actions.MakeFullExpr(Cond.get(), WhileLoc)); + + // C99 6.8.5p5 - In C99, the body of the if statement is a scope, even if + // there is no compound stmt. C90 does not have this clause. We only do this + // if the body isn't a compound statement to avoid push/pop in common cases. + // + // C++ 6.5p2: + // The substatement in an iteration-statement implicitly defines a local scope + // which is entered and exited each time through the loop. + // + // See comments in ParseIfStatement for why we create a scope for the + // condition and a new scope for substatement in C++. + // + ParseScope InnerScope(this, Scope::DeclScope, + C99orCXX && Tok.isNot(tok::l_brace)); + + // Read the body statement. + StmtResult Body(ParseStatement(TrailingElseLoc)); + + // Pop the body scope if needed. + InnerScope.Exit(); + WhileScope.Exit(); + + if ((Cond.isInvalid() && !CondVar) || Body.isInvalid()) + return StmtError(); + + return Actions.ActOnWhileStmt(WhileLoc, FullCond, CondVar, Body.get()); +} + +/// ParseDoStatement +/// do-statement: [C99 6.8.5.2] +/// 'do' statement 'while' '(' expression ')' ';' +/// Note: this lets the caller parse the end ';'. +StmtResult Parser::ParseDoStatement() { + assert(Tok.is(tok::kw_do) && "Not a do stmt!"); + SourceLocation DoLoc = ConsumeToken(); // eat the 'do'. + + // C99 6.8.5p5 - In C99, the do statement is a block. This is not + // the case for C90. Start the loop scope. + unsigned ScopeFlags; + if (getLangOpts().C99) + ScopeFlags = Scope::BreakScope | Scope::ContinueScope | Scope::DeclScope; + else + ScopeFlags = Scope::BreakScope | Scope::ContinueScope; + + ParseScope DoScope(this, ScopeFlags); + + // C99 6.8.5p5 - In C99, the body of the if statement is a scope, even if + // there is no compound stmt. C90 does not have this clause. We only do this + // if the body isn't a compound statement to avoid push/pop in common cases. + // + // C++ 6.5p2: + // The substatement in an iteration-statement implicitly defines a local scope + // which is entered and exited each time through the loop. + // + ParseScope InnerScope(this, Scope::DeclScope, + (getLangOpts().C99 || getLangOpts().CPlusPlus) && + Tok.isNot(tok::l_brace)); + + // Read the body statement. + StmtResult Body(ParseStatement()); + + // Pop the body scope if needed. + InnerScope.Exit(); + + if (Tok.isNot(tok::kw_while)) { + if (!Body.isInvalid()) { + Diag(Tok, diag::err_expected_while); + Diag(DoLoc, diag::note_matching) << "do"; + SkipUntil(tok::semi, StopBeforeMatch); + } + return StmtError(); + } + SourceLocation WhileLoc = ConsumeToken(); + + if (Tok.isNot(tok::l_paren)) { + Diag(Tok, diag::err_expected_lparen_after) << "do/while"; + SkipUntil(tok::semi, StopBeforeMatch); + return StmtError(); + } + + // Parse the parenthesized expression. + BalancedDelimiterTracker T(*this, tok::l_paren); + T.consumeOpen(); + + // A do-while expression is not a condition, so can't have attributes. + DiagnoseAndSkipCXX11Attributes(); + + ExprResult Cond = ParseExpression(); + T.consumeClose(); + DoScope.Exit(); + + if (Cond.isInvalid() || Body.isInvalid()) + return StmtError(); + + return Actions.ActOnDoStmt(DoLoc, Body.get(), WhileLoc, T.getOpenLocation(), + Cond.get(), T.getCloseLocation()); +} + +/// ParseForStatement +/// for-statement: [C99 6.8.5.3] +/// 'for' '(' expr[opt] ';' expr[opt] ';' expr[opt] ')' statement +/// 'for' '(' declaration expr[opt] ';' expr[opt] ')' statement +/// [C++] 'for' '(' for-init-statement condition[opt] ';' expression[opt] ')' +/// [C++] statement +/// [C++0x] 'for' '(' for-range-declaration : for-range-initializer ) statement +/// [OBJC2] 'for' '(' declaration 'in' expr ')' statement +/// [OBJC2] 'for' '(' expr 'in' expr ')' statement +/// +/// [C++] for-init-statement: +/// [C++] expression-statement +/// [C++] simple-declaration +/// +/// [C++0x] for-range-declaration: +/// [C++0x] attribute-specifier-seq[opt] type-specifier-seq declarator +/// [C++0x] for-range-initializer: +/// [C++0x] expression +/// [C++0x] braced-init-list [TODO] +StmtResult Parser::ParseForStatement(SourceLocation *TrailingElseLoc) { + assert(Tok.is(tok::kw_for) && "Not a for stmt!"); + SourceLocation ForLoc = ConsumeToken(); // eat the 'for'. + + if (Tok.isNot(tok::l_paren)) { + Diag(Tok, diag::err_expected_lparen_after) << "for"; + SkipUntil(tok::semi); + return StmtError(); + } + + bool C99orCXXorObjC = getLangOpts().C99 || getLangOpts().CPlusPlus || + getLangOpts().ObjC1; + + // C99 6.8.5p5 - In C99, the for statement is a block. This is not + // the case for C90. Start the loop scope. + // + // C++ 6.4p3: + // A name introduced by a declaration in a condition is in scope from its + // point of declaration until the end of the substatements controlled by the + // condition. + // C++ 3.3.2p4: + // Names declared in the for-init-statement, and in the condition of if, + // while, for, and switch statements are local to the if, while, for, or + // switch statement (including the controlled statement). + // C++ 6.5.3p1: + // Names declared in the for-init-statement are in the same declarative-region + // as those declared in the condition. + // + unsigned ScopeFlags; + if (C99orCXXorObjC) + ScopeFlags = Scope::BreakScope | Scope::ContinueScope | + Scope::DeclScope | Scope::ControlScope; + else + ScopeFlags = Scope::BreakScope | Scope::ContinueScope; + + ParseScope ForScope(this, ScopeFlags); + + BalancedDelimiterTracker T(*this, tok::l_paren); + T.consumeOpen(); + + ExprResult Value; + + bool ForEach = false, ForRange = false; + StmtResult FirstPart; + bool SecondPartIsInvalid = false; + FullExprArg SecondPart(Actions); + ExprResult Collection; + ForRangeInit ForRangeInit; + FullExprArg ThirdPart(Actions); + Decl *SecondVar = 0; + + if (Tok.is(tok::code_completion)) { + Actions.CodeCompleteOrdinaryName(getCurScope(), + C99orCXXorObjC? Sema::PCC_ForInit + : Sema::PCC_Expression); + cutOffParsing(); + return StmtError(); + } + + ParsedAttributesWithRange attrs(AttrFactory); + MaybeParseCXX11Attributes(attrs); + + // Parse the first part of the for specifier. + if (Tok.is(tok::semi)) { // for (; + ProhibitAttributes(attrs); + // no first part, eat the ';'. + ConsumeToken(); + } else if (isForInitDeclaration()) { // for (int X = 4; + // Parse declaration, which eats the ';'. + if (!C99orCXXorObjC) // Use of C99-style for loops in C90 mode? + Diag(Tok, diag::ext_c99_variable_decl_in_for_loop); + + // In C++0x, "for (T NS:a" might not be a typo for :: + bool MightBeForRangeStmt = getLangOpts().CPlusPlus; + ColonProtectionRAIIObject ColonProtection(*this, MightBeForRangeStmt); + + SourceLocation DeclStart = Tok.getLocation(), DeclEnd; + StmtVector Stmts; + DeclGroupPtrTy DG = ParseSimpleDeclaration(Stmts, Declarator::ForContext, + DeclEnd, attrs, false, + MightBeForRangeStmt ? + &ForRangeInit : 0); + FirstPart = Actions.ActOnDeclStmt(DG, DeclStart, Tok.getLocation()); + + if (ForRangeInit.ParsedForRangeDecl()) { + Diag(ForRangeInit.ColonLoc, getLangOpts().CPlusPlus11 ? + diag::warn_cxx98_compat_for_range : diag::ext_for_range); + + ForRange = true; + } else if (Tok.is(tok::semi)) { // for (int x = 4; + ConsumeToken(); + } else if ((ForEach = isTokIdentifier_in())) { + Actions.ActOnForEachDeclStmt(DG); + // ObjC: for (id x in expr) + ConsumeToken(); // consume 'in' + + if (Tok.is(tok::code_completion)) { + Actions.CodeCompleteObjCForCollection(getCurScope(), DG); + cutOffParsing(); + return StmtError(); + } + Collection = ParseExpression(); + } else { + Diag(Tok, diag::err_expected_semi_for); + } + } else { + ProhibitAttributes(attrs); + Value = ParseExpression(); + + ForEach = isTokIdentifier_in(); + + // Turn the expression into a stmt. + if (!Value.isInvalid()) { + if (ForEach) + FirstPart = Actions.ActOnForEachLValueExpr(Value.get()); + else + FirstPart = Actions.ActOnExprStmt(Value); + } + + if (Tok.is(tok::semi)) { + ConsumeToken(); + } else if (ForEach) { + ConsumeToken(); // consume 'in' + + if (Tok.is(tok::code_completion)) { + Actions.CodeCompleteObjCForCollection(getCurScope(), DeclGroupPtrTy()); + cutOffParsing(); + return StmtError(); + } + Collection = ParseExpression(); + } else if (getLangOpts().CPlusPlus11 && Tok.is(tok::colon) && FirstPart.get()) { + // User tried to write the reasonable, but ill-formed, for-range-statement + // for (expr : expr) { ... } + Diag(Tok, diag::err_for_range_expected_decl) + << FirstPart.get()->getSourceRange(); + SkipUntil(tok::r_paren, StopBeforeMatch); + SecondPartIsInvalid = true; + } else { + if (!Value.isInvalid()) { + Diag(Tok, diag::err_expected_semi_for); + } else { + // Skip until semicolon or rparen, don't consume it. + SkipUntil(tok::r_paren, StopAtSemi | StopBeforeMatch); + if (Tok.is(tok::semi)) + ConsumeToken(); + } + } + } + if (!ForEach && !ForRange) { + assert(!SecondPart.get() && "Shouldn't have a second expression yet."); + // Parse the second part of the for specifier. + if (Tok.is(tok::semi)) { // for (...;; + // no second part. + } else if (Tok.is(tok::r_paren)) { + // missing both semicolons. + } else { + ExprResult Second; + if (getLangOpts().CPlusPlus) + ParseCXXCondition(Second, SecondVar, ForLoc, true); + else { + Second = ParseExpression(); + if (!Second.isInvalid()) + Second = Actions.ActOnBooleanCondition(getCurScope(), ForLoc, + Second.get()); + } + SecondPartIsInvalid = Second.isInvalid(); + SecondPart = Actions.MakeFullExpr(Second.get(), ForLoc); + } + + if (Tok.isNot(tok::semi)) { + if (!SecondPartIsInvalid || SecondVar) + Diag(Tok, diag::err_expected_semi_for); + else + // Skip until semicolon or rparen, don't consume it. + SkipUntil(tok::r_paren, StopAtSemi | StopBeforeMatch); + } + + if (Tok.is(tok::semi)) { + ConsumeToken(); + } + + // Parse the third part of the for specifier. + if (Tok.isNot(tok::r_paren)) { // for (...;...;) + ExprResult Third = ParseExpression(); + // FIXME: The C++11 standard doesn't actually say that this is a + // discarded-value expression, but it clearly should be. + ThirdPart = Actions.MakeFullDiscardedValueExpr(Third.take()); + } + } + // Match the ')'. + T.consumeClose(); + + // We need to perform most of the semantic analysis for a C++0x for-range + // statememt before parsing the body, in order to be able to deduce the type + // of an auto-typed loop variable. + StmtResult ForRangeStmt; + StmtResult ForEachStmt; + + if (ForRange) { + ForRangeStmt = Actions.ActOnCXXForRangeStmt(ForLoc, FirstPart.take(), + ForRangeInit.ColonLoc, + ForRangeInit.RangeExpr.get(), + T.getCloseLocation(), + Sema::BFRK_Build); + + + // Similarly, we need to do the semantic analysis for a for-range + // statement immediately in order to close over temporaries correctly. + } else if (ForEach) { + ForEachStmt = Actions.ActOnObjCForCollectionStmt(ForLoc, + FirstPart.take(), + Collection.take(), + T.getCloseLocation()); + } + + // C99 6.8.5p5 - In C99, the body of the if statement is a scope, even if + // there is no compound stmt. C90 does not have this clause. We only do this + // if the body isn't a compound statement to avoid push/pop in common cases. + // + // C++ 6.5p2: + // The substatement in an iteration-statement implicitly defines a local scope + // which is entered and exited each time through the loop. + // + // See comments in ParseIfStatement for why we create a scope for + // for-init-statement/condition and a new scope for substatement in C++. + // + ParseScope InnerScope(this, Scope::DeclScope, + C99orCXXorObjC && Tok.isNot(tok::l_brace)); + + // Read the body statement. + StmtResult Body(ParseStatement(TrailingElseLoc)); + + // Pop the body scope if needed. + InnerScope.Exit(); + + // Leave the for-scope. + ForScope.Exit(); + + if (Body.isInvalid()) + return StmtError(); + + if (ForEach) + return Actions.FinishObjCForCollectionStmt(ForEachStmt.take(), + Body.take()); + + if (ForRange) + return Actions.FinishCXXForRangeStmt(ForRangeStmt.take(), Body.take()); + + return Actions.ActOnForStmt(ForLoc, T.getOpenLocation(), FirstPart.take(), + SecondPart, SecondVar, ThirdPart, + T.getCloseLocation(), Body.take()); +} + +/// ParseGotoStatement +/// jump-statement: +/// 'goto' identifier ';' +/// [GNU] 'goto' '*' expression ';' +/// +/// Note: this lets the caller parse the end ';'. +/// +StmtResult Parser::ParseGotoStatement() { + assert(Tok.is(tok::kw_goto) && "Not a goto stmt!"); + SourceLocation GotoLoc = ConsumeToken(); // eat the 'goto'. + + StmtResult Res; + if (Tok.is(tok::identifier)) { + LabelDecl *LD = Actions.LookupOrCreateLabel(Tok.getIdentifierInfo(), + Tok.getLocation()); + Res = Actions.ActOnGotoStmt(GotoLoc, Tok.getLocation(), LD); + ConsumeToken(); + } else if (Tok.is(tok::star)) { + // GNU indirect goto extension. + Diag(Tok, diag::ext_gnu_indirect_goto); + SourceLocation StarLoc = ConsumeToken(); + ExprResult R(ParseExpression()); + if (R.isInvalid()) { // Skip to the semicolon, but don't consume it. + SkipUntil(tok::semi, StopBeforeMatch); + return StmtError(); + } + Res = Actions.ActOnIndirectGotoStmt(GotoLoc, StarLoc, R.take()); + } else { + Diag(Tok, diag::err_expected_ident); + return StmtError(); + } + + return Res; +} + +/// ParseContinueStatement +/// jump-statement: +/// 'continue' ';' +/// +/// Note: this lets the caller parse the end ';'. +/// +StmtResult Parser::ParseContinueStatement() { + SourceLocation ContinueLoc = ConsumeToken(); // eat the 'continue'. + return Actions.ActOnContinueStmt(ContinueLoc, getCurScope()); +} + +/// ParseBreakStatement +/// jump-statement: +/// 'break' ';' +/// +/// Note: this lets the caller parse the end ';'. +/// +StmtResult Parser::ParseBreakStatement() { + SourceLocation BreakLoc = ConsumeToken(); // eat the 'break'. + return Actions.ActOnBreakStmt(BreakLoc, getCurScope()); +} + +/// ParseReturnStatement +/// jump-statement: +/// 'return' expression[opt] ';' +StmtResult Parser::ParseReturnStatement() { + assert(Tok.is(tok::kw_return) && "Not a return stmt!"); + SourceLocation ReturnLoc = ConsumeToken(); // eat the 'return'. + + ExprResult R; + if (Tok.isNot(tok::semi)) { + if (Tok.is(tok::code_completion)) { + Actions.CodeCompleteReturn(getCurScope()); + cutOffParsing(); + return StmtError(); + } + + if (Tok.is(tok::l_brace) && getLangOpts().CPlusPlus) { + R = ParseInitializer(); + if (R.isUsable()) + Diag(R.get()->getLocStart(), getLangOpts().CPlusPlus11 ? + diag::warn_cxx98_compat_generalized_initializer_lists : + diag::ext_generalized_initializer_lists) + << R.get()->getSourceRange(); + } else + R = ParseExpression(); + if (R.isInvalid()) { // Skip to the semicolon, but don't consume it. + SkipUntil(tok::semi, StopBeforeMatch); + return StmtError(); + } + } + return Actions.ActOnReturnStmt(ReturnLoc, R.take()); +} + +namespace { + class ClangAsmParserCallback : public llvm::MCAsmParserSemaCallback { + Parser &TheParser; + SourceLocation AsmLoc; + StringRef AsmString; + + /// The tokens we streamed into AsmString and handed off to MC. + ArrayRef<Token> AsmToks; + + /// The offset of each token in AsmToks within AsmString. + ArrayRef<unsigned> AsmTokOffsets; + + public: + ClangAsmParserCallback(Parser &P, SourceLocation Loc, + StringRef AsmString, + ArrayRef<Token> Toks, + ArrayRef<unsigned> Offsets) + : TheParser(P), AsmLoc(Loc), AsmString(AsmString), + AsmToks(Toks), AsmTokOffsets(Offsets) { + assert(AsmToks.size() == AsmTokOffsets.size()); + } + + void *LookupInlineAsmIdentifier(StringRef &LineBuf, + InlineAsmIdentifierInfo &Info, + bool IsUnevaluatedContext) { + // Collect the desired tokens. + SmallVector<Token, 16> LineToks; + const Token *FirstOrigToken = 0; + findTokensForString(LineBuf, LineToks, FirstOrigToken); + + unsigned NumConsumedToks; + ExprResult Result = + TheParser.ParseMSAsmIdentifier(LineToks, NumConsumedToks, &Info, + IsUnevaluatedContext); + + // If we consumed the entire line, tell MC that. + // Also do this if we consumed nothing as a way of reporting failure. + if (NumConsumedToks == 0 || NumConsumedToks == LineToks.size()) { + // By not modifying LineBuf, we're implicitly consuming it all. + + // Otherwise, consume up to the original tokens. + } else { + assert(FirstOrigToken && "not using original tokens?"); + + // Since we're using original tokens, apply that offset. + assert(FirstOrigToken[NumConsumedToks].getLocation() + == LineToks[NumConsumedToks].getLocation()); + unsigned FirstIndex = FirstOrigToken - AsmToks.begin(); + unsigned LastIndex = FirstIndex + NumConsumedToks - 1; + + // The total length we've consumed is the relative offset + // of the last token we consumed plus its length. + unsigned TotalOffset = (AsmTokOffsets[LastIndex] + + AsmToks[LastIndex].getLength() + - AsmTokOffsets[FirstIndex]); + LineBuf = LineBuf.substr(0, TotalOffset); + } + + // Initialize the "decl" with the lookup result. + Info.OpDecl = static_cast<void*>(Result.take()); + return Info.OpDecl; + } + + bool LookupInlineAsmField(StringRef Base, StringRef Member, + unsigned &Offset) { + return TheParser.getActions().LookupInlineAsmField(Base, Member, + Offset, AsmLoc); + } + + static void DiagHandlerCallback(const llvm::SMDiagnostic &D, + void *Context) { + ((ClangAsmParserCallback*) Context)->handleDiagnostic(D); + } + + private: + /// Collect the appropriate tokens for the given string. + void findTokensForString(StringRef Str, SmallVectorImpl<Token> &TempToks, + const Token *&FirstOrigToken) const { + // For now, assert that the string we're working with is a substring + // of what we gave to MC. This lets us use the original tokens. + assert(!std::less<const char*>()(Str.begin(), AsmString.begin()) && + !std::less<const char*>()(AsmString.end(), Str.end())); + + // Try to find a token whose offset matches the first token. + unsigned FirstCharOffset = Str.begin() - AsmString.begin(); + const unsigned *FirstTokOffset + = std::lower_bound(AsmTokOffsets.begin(), AsmTokOffsets.end(), + FirstCharOffset); + + // For now, assert that the start of the string exactly + // corresponds to the start of a token. + assert(*FirstTokOffset == FirstCharOffset); + + // Use all the original tokens for this line. (We assume the + // end of the line corresponds cleanly to a token break.) + unsigned FirstTokIndex = FirstTokOffset - AsmTokOffsets.begin(); + FirstOrigToken = &AsmToks[FirstTokIndex]; + unsigned LastCharOffset = Str.end() - AsmString.begin(); + for (unsigned i = FirstTokIndex, e = AsmTokOffsets.size(); i != e; ++i) { + if (AsmTokOffsets[i] >= LastCharOffset) break; + TempToks.push_back(AsmToks[i]); + } + } + + void handleDiagnostic(const llvm::SMDiagnostic &D) { + // Compute an offset into the inline asm buffer. + // FIXME: This isn't right if .macro is involved (but hopefully, no + // real-world code does that). + const llvm::SourceMgr &LSM = *D.getSourceMgr(); + const llvm::MemoryBuffer *LBuf = + LSM.getMemoryBuffer(LSM.FindBufferContainingLoc(D.getLoc())); + unsigned Offset = D.getLoc().getPointer() - LBuf->getBufferStart(); + + // Figure out which token that offset points into. + const unsigned *TokOffsetPtr = + std::lower_bound(AsmTokOffsets.begin(), AsmTokOffsets.end(), Offset); + unsigned TokIndex = TokOffsetPtr - AsmTokOffsets.begin(); + unsigned TokOffset = *TokOffsetPtr; + + // If we come up with an answer which seems sane, use it; otherwise, + // just point at the __asm keyword. + // FIXME: Assert the answer is sane once we handle .macro correctly. + SourceLocation Loc = AsmLoc; + if (TokIndex < AsmToks.size()) { + const Token &Tok = AsmToks[TokIndex]; + Loc = Tok.getLocation(); + Loc = Loc.getLocWithOffset(Offset - TokOffset); + } + TheParser.Diag(Loc, diag::err_inline_ms_asm_parsing) + << D.getMessage(); + } + }; +} + +/// Parse an identifier in an MS-style inline assembly block. +/// +/// \param CastInfo - a void* so that we don't have to teach Parser.h +/// about the actual type. +ExprResult Parser::ParseMSAsmIdentifier(llvm::SmallVectorImpl<Token> &LineToks, + unsigned &NumLineToksConsumed, + void *CastInfo, + bool IsUnevaluatedContext) { + llvm::InlineAsmIdentifierInfo &Info = + *(llvm::InlineAsmIdentifierInfo *) CastInfo; + + // Push a fake token on the end so that we don't overrun the token + // stream. We use ';' because it expression-parsing should never + // overrun it. + const tok::TokenKind EndOfStream = tok::semi; + Token EndOfStreamTok; + EndOfStreamTok.startToken(); + EndOfStreamTok.setKind(EndOfStream); + LineToks.push_back(EndOfStreamTok); + + // Also copy the current token over. + LineToks.push_back(Tok); + + PP.EnterTokenStream(LineToks.begin(), + LineToks.size(), + /*disable macros*/ true, + /*owns tokens*/ false); + + // Clear the current token and advance to the first token in LineToks. + ConsumeAnyToken(); + + // Parse an optional scope-specifier if we're in C++. + CXXScopeSpec SS; + if (getLangOpts().CPlusPlus) { + ParseOptionalCXXScopeSpecifier(SS, ParsedType(), /*EnteringContext=*/false); + } + + // Require an identifier here. + SourceLocation TemplateKWLoc; + UnqualifiedId Id; + bool Invalid = ParseUnqualifiedId(SS, + /*EnteringContext=*/false, + /*AllowDestructorName=*/false, + /*AllowConstructorName=*/false, + /*ObjectType=*/ ParsedType(), + TemplateKWLoc, + Id); + + // If we've run into the poison token we inserted before, or there + // was a parsing error, then claim the entire line. + if (Invalid || Tok.is(EndOfStream)) { + NumLineToksConsumed = LineToks.size() - 2; + + // Otherwise, claim up to the start of the next token. + } else { + // Figure out how many tokens we are into LineToks. + unsigned LineIndex = 0; + while (LineToks[LineIndex].getLocation() != Tok.getLocation()) { + LineIndex++; + assert(LineIndex < LineToks.size() - 2); // we added two extra tokens + } + + NumLineToksConsumed = LineIndex; + } + + // Finally, restore the old parsing state by consuming all the + // tokens we staged before, implicitly killing off the + // token-lexer we pushed. + for (unsigned n = LineToks.size() - 2 - NumLineToksConsumed; n != 0; --n) { + ConsumeAnyToken(); + } + ConsumeToken(EndOfStream); + + // Leave LineToks in its original state. + LineToks.pop_back(); + LineToks.pop_back(); + + // Perform the lookup. + return Actions.LookupInlineAsmIdentifier(SS, TemplateKWLoc, Id, Info, + IsUnevaluatedContext); +} + +/// Turn a sequence of our tokens back into a string that we can hand +/// to the MC asm parser. +static bool buildMSAsmString(Preprocessor &PP, + SourceLocation AsmLoc, + ArrayRef<Token> AsmToks, + SmallVectorImpl<unsigned> &TokOffsets, + SmallString<512> &Asm) { + assert (!AsmToks.empty() && "Didn't expect an empty AsmToks!"); + + // Is this the start of a new assembly statement? + bool isNewStatement = true; + + for (unsigned i = 0, e = AsmToks.size(); i < e; ++i) { + const Token &Tok = AsmToks[i]; + + // Start each new statement with a newline and a tab. + if (!isNewStatement && + (Tok.is(tok::kw_asm) || Tok.isAtStartOfLine())) { + Asm += "\n\t"; + isNewStatement = true; + } + + // Preserve the existence of leading whitespace except at the + // start of a statement. + if (!isNewStatement && Tok.hasLeadingSpace()) + Asm += ' '; + + // Remember the offset of this token. + TokOffsets.push_back(Asm.size()); + + // Don't actually write '__asm' into the assembly stream. + if (Tok.is(tok::kw_asm)) { + // Complain about __asm at the end of the stream. + if (i + 1 == e) { + PP.Diag(AsmLoc, diag::err_asm_empty); + return true; + } + + continue; + } + + // Append the spelling of the token. + SmallString<32> SpellingBuffer; + bool SpellingInvalid = false; + Asm += PP.getSpelling(Tok, SpellingBuffer, &SpellingInvalid); + assert(!SpellingInvalid && "spelling was invalid after correct parse?"); + + // We are no longer at the start of a statement. + isNewStatement = false; + } + + // Ensure that the buffer is null-terminated. + Asm.push_back('\0'); + Asm.pop_back(); + + assert(TokOffsets.size() == AsmToks.size()); + return false; +} + +/// ParseMicrosoftAsmStatement. When -fms-extensions/-fasm-blocks is enabled, +/// this routine is called to collect the tokens for an MS asm statement. +/// +/// [MS] ms-asm-statement: +/// ms-asm-block +/// ms-asm-block ms-asm-statement +/// +/// [MS] ms-asm-block: +/// '__asm' ms-asm-line '\n' +/// '__asm' '{' ms-asm-instruction-block[opt] '}' ';'[opt] +/// +/// [MS] ms-asm-instruction-block +/// ms-asm-line +/// ms-asm-line '\n' ms-asm-instruction-block +/// +StmtResult Parser::ParseMicrosoftAsmStatement(SourceLocation AsmLoc) { + SourceManager &SrcMgr = PP.getSourceManager(); + SourceLocation EndLoc = AsmLoc; + SmallVector<Token, 4> AsmToks; + + bool InBraces = false; + unsigned short savedBraceCount = 0; + bool InAsmComment = false; + FileID FID; + unsigned LineNo = 0; + unsigned NumTokensRead = 0; + SourceLocation LBraceLoc; + + if (Tok.is(tok::l_brace)) { + // Braced inline asm: consume the opening brace. + InBraces = true; + savedBraceCount = BraceCount; + EndLoc = LBraceLoc = ConsumeBrace(); + ++NumTokensRead; + } else { + // Single-line inline asm; compute which line it is on. + std::pair<FileID, unsigned> ExpAsmLoc = + SrcMgr.getDecomposedExpansionLoc(EndLoc); + FID = ExpAsmLoc.first; + LineNo = SrcMgr.getLineNumber(FID, ExpAsmLoc.second); + } + + SourceLocation TokLoc = Tok.getLocation(); + do { + // If we hit EOF, we're done, period. + if (Tok.is(tok::eof)) + break; + + if (!InAsmComment && Tok.is(tok::semi)) { + // A semicolon in an asm is the start of a comment. + InAsmComment = true; + if (InBraces) { + // Compute which line the comment is on. + std::pair<FileID, unsigned> ExpSemiLoc = + SrcMgr.getDecomposedExpansionLoc(TokLoc); + FID = ExpSemiLoc.first; + LineNo = SrcMgr.getLineNumber(FID, ExpSemiLoc.second); + } + } else if (!InBraces || InAsmComment) { + // If end-of-line is significant, check whether this token is on a + // new line. + std::pair<FileID, unsigned> ExpLoc = + SrcMgr.getDecomposedExpansionLoc(TokLoc); + if (ExpLoc.first != FID || + SrcMgr.getLineNumber(ExpLoc.first, ExpLoc.second) != LineNo) { + // If this is a single-line __asm, we're done. + if (!InBraces) + break; + // We're no longer in a comment. + InAsmComment = false; + } else if (!InAsmComment && Tok.is(tok::r_brace)) { + // Single-line asm always ends when a closing brace is seen. + // FIXME: This is compatible with Apple gcc's -fasm-blocks; what + // does MSVC do here? + break; + } + } + if (!InAsmComment && InBraces && Tok.is(tok::r_brace) && + BraceCount == (savedBraceCount + 1)) { + // Consume the closing brace, and finish + EndLoc = ConsumeBrace(); + break; + } + + // Consume the next token; make sure we don't modify the brace count etc. + // if we are in a comment. + EndLoc = TokLoc; + if (InAsmComment) + PP.Lex(Tok); + else { + AsmToks.push_back(Tok); + ConsumeAnyToken(); + } + TokLoc = Tok.getLocation(); + ++NumTokensRead; + } while (1); + + if (InBraces && BraceCount != savedBraceCount) { + // __asm without closing brace (this can happen at EOF). + Diag(Tok, diag::err_expected_rbrace); + Diag(LBraceLoc, diag::note_matching) << "{"; + return StmtError(); + } else if (NumTokensRead == 0) { + // Empty __asm. + Diag(Tok, diag::err_expected_lbrace); + return StmtError(); + } + + // Okay, prepare to use MC to parse the assembly. + SmallVector<StringRef, 4> ConstraintRefs; + SmallVector<Expr*, 4> Exprs; + SmallVector<StringRef, 4> ClobberRefs; + + // We need an actual supported target. + llvm::Triple TheTriple = Actions.Context.getTargetInfo().getTriple(); + llvm::Triple::ArchType ArchTy = TheTriple.getArch(); + const std::string &TT = TheTriple.getTriple(); + const llvm::Target *TheTarget = 0; + bool UnsupportedArch = (ArchTy != llvm::Triple::x86 && + ArchTy != llvm::Triple::x86_64); + if (UnsupportedArch) { + Diag(AsmLoc, diag::err_msasm_unsupported_arch) << TheTriple.getArchName(); + } else { + std::string Error; + TheTarget = llvm::TargetRegistry::lookupTarget(TT, Error); + if (!TheTarget) + Diag(AsmLoc, diag::err_msasm_unable_to_create_target) << Error; + } + + // If we don't support assembly, or the assembly is empty, we don't + // need to instantiate the AsmParser, etc. + if (!TheTarget || AsmToks.empty()) { + return Actions.ActOnMSAsmStmt(AsmLoc, LBraceLoc, AsmToks, StringRef(), + /*NumOutputs*/ 0, /*NumInputs*/ 0, + ConstraintRefs, ClobberRefs, Exprs, EndLoc); + } + + // Expand the tokens into a string buffer. + SmallString<512> AsmString; + SmallVector<unsigned, 8> TokOffsets; + if (buildMSAsmString(PP, AsmLoc, AsmToks, TokOffsets, AsmString)) + return StmtError(); + + OwningPtr<llvm::MCRegisterInfo> MRI(TheTarget->createMCRegInfo(TT)); + OwningPtr<llvm::MCAsmInfo> MAI(TheTarget->createMCAsmInfo(*MRI, TT)); + // Get the instruction descriptor. + const llvm::MCInstrInfo *MII = TheTarget->createMCInstrInfo(); + OwningPtr<llvm::MCObjectFileInfo> MOFI(new llvm::MCObjectFileInfo()); + OwningPtr<llvm::MCSubtargetInfo> + STI(TheTarget->createMCSubtargetInfo(TT, "", "")); + + llvm::SourceMgr TempSrcMgr; + llvm::MCContext Ctx(MAI.get(), MRI.get(), MOFI.get(), &TempSrcMgr); + llvm::MemoryBuffer *Buffer = + llvm::MemoryBuffer::getMemBuffer(AsmString, "<MS inline asm>"); + + // Tell SrcMgr about this buffer, which is what the parser will pick up. + TempSrcMgr.AddNewSourceBuffer(Buffer, llvm::SMLoc()); + + OwningPtr<llvm::MCStreamer> Str(createNullStreamer(Ctx)); + OwningPtr<llvm::MCAsmParser> + Parser(createMCAsmParser(TempSrcMgr, Ctx, *Str.get(), *MAI)); + OwningPtr<llvm::MCTargetAsmParser> + TargetParser(TheTarget->createMCAsmParser(*STI, *Parser, *MII)); + + llvm::MCInstPrinter *IP = + TheTarget->createMCInstPrinter(1, *MAI, *MII, *MRI, *STI); + + // Change to the Intel dialect. + Parser->setAssemblerDialect(1); + Parser->setTargetParser(*TargetParser.get()); + Parser->setParsingInlineAsm(true); + TargetParser->setParsingInlineAsm(true); + + ClangAsmParserCallback Callback(*this, AsmLoc, AsmString, + AsmToks, TokOffsets); + TargetParser->setSemaCallback(&Callback); + TempSrcMgr.setDiagHandler(ClangAsmParserCallback::DiagHandlerCallback, + &Callback); + + unsigned NumOutputs; + unsigned NumInputs; + std::string AsmStringIR; + SmallVector<std::pair<void *, bool>, 4> OpExprs; + SmallVector<std::string, 4> Constraints; + SmallVector<std::string, 4> Clobbers; + if (Parser->parseMSInlineAsm(AsmLoc.getPtrEncoding(), AsmStringIR, + NumOutputs, NumInputs, OpExprs, Constraints, + Clobbers, MII, IP, Callback)) + return StmtError(); + + // Build the vector of clobber StringRefs. + unsigned NumClobbers = Clobbers.size(); + ClobberRefs.resize(NumClobbers); + for (unsigned i = 0; i != NumClobbers; ++i) + ClobberRefs[i] = StringRef(Clobbers[i]); + + // Recast the void pointers and build the vector of constraint StringRefs. + unsigned NumExprs = NumOutputs + NumInputs; + ConstraintRefs.resize(NumExprs); + Exprs.resize(NumExprs); + for (unsigned i = 0, e = NumExprs; i != e; ++i) { + Expr *OpExpr = static_cast<Expr *>(OpExprs[i].first); + if (!OpExpr) + return StmtError(); + + // Need address of variable. + if (OpExprs[i].second) + OpExpr = Actions.BuildUnaryOp(getCurScope(), AsmLoc, UO_AddrOf, OpExpr) + .take(); + + ConstraintRefs[i] = StringRef(Constraints[i]); + Exprs[i] = OpExpr; + } + + // FIXME: We should be passing source locations for better diagnostics. + return Actions.ActOnMSAsmStmt(AsmLoc, LBraceLoc, AsmToks, AsmStringIR, + NumOutputs, NumInputs, + ConstraintRefs, ClobberRefs, Exprs, EndLoc); +} + +/// ParseAsmStatement - Parse a GNU extended asm statement. +/// asm-statement: +/// gnu-asm-statement +/// ms-asm-statement +/// +/// [GNU] gnu-asm-statement: +/// 'asm' type-qualifier[opt] '(' asm-argument ')' ';' +/// +/// [GNU] asm-argument: +/// asm-string-literal +/// asm-string-literal ':' asm-operands[opt] +/// asm-string-literal ':' asm-operands[opt] ':' asm-operands[opt] +/// asm-string-literal ':' asm-operands[opt] ':' asm-operands[opt] +/// ':' asm-clobbers +/// +/// [GNU] asm-clobbers: +/// asm-string-literal +/// asm-clobbers ',' asm-string-literal +/// +StmtResult Parser::ParseAsmStatement(bool &msAsm) { + assert(Tok.is(tok::kw_asm) && "Not an asm stmt"); + SourceLocation AsmLoc = ConsumeToken(); + + if (getLangOpts().AsmBlocks && Tok.isNot(tok::l_paren) && + !isTypeQualifier()) { + msAsm = true; + return ParseMicrosoftAsmStatement(AsmLoc); + } + DeclSpec DS(AttrFactory); + SourceLocation Loc = Tok.getLocation(); + ParseTypeQualifierListOpt(DS, true, false); + + // GNU asms accept, but warn, about type-qualifiers other than volatile. + if (DS.getTypeQualifiers() & DeclSpec::TQ_const) + Diag(Loc, diag::w_asm_qualifier_ignored) << "const"; + if (DS.getTypeQualifiers() & DeclSpec::TQ_restrict) + Diag(Loc, diag::w_asm_qualifier_ignored) << "restrict"; + // FIXME: Once GCC supports _Atomic, check whether it permits it here. + if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic) + Diag(Loc, diag::w_asm_qualifier_ignored) << "_Atomic"; + + // Remember if this was a volatile asm. + bool isVolatile = DS.getTypeQualifiers() & DeclSpec::TQ_volatile; + if (Tok.isNot(tok::l_paren)) { + Diag(Tok, diag::err_expected_lparen_after) << "asm"; + SkipUntil(tok::r_paren, StopAtSemi); + return StmtError(); + } + BalancedDelimiterTracker T(*this, tok::l_paren); + T.consumeOpen(); + + ExprResult AsmString(ParseAsmStringLiteral()); + if (AsmString.isInvalid()) { + // Consume up to and including the closing paren. + T.skipToEnd(); + return StmtError(); + } + + SmallVector<IdentifierInfo *, 4> Names; + ExprVector Constraints; + ExprVector Exprs; + ExprVector Clobbers; + + if (Tok.is(tok::r_paren)) { + // We have a simple asm expression like 'asm("foo")'. + T.consumeClose(); + return Actions.ActOnGCCAsmStmt(AsmLoc, /*isSimple*/ true, isVolatile, + /*NumOutputs*/ 0, /*NumInputs*/ 0, 0, + Constraints, Exprs, AsmString.take(), + Clobbers, T.getCloseLocation()); + } + + // Parse Outputs, if present. + bool AteExtraColon = false; + if (Tok.is(tok::colon) || Tok.is(tok::coloncolon)) { + // In C++ mode, parse "::" like ": :". + AteExtraColon = Tok.is(tok::coloncolon); + ConsumeToken(); + + if (!AteExtraColon && + ParseAsmOperandsOpt(Names, Constraints, Exprs)) + return StmtError(); + } + + unsigned NumOutputs = Names.size(); + + // Parse Inputs, if present. + if (AteExtraColon || + Tok.is(tok::colon) || Tok.is(tok::coloncolon)) { + // In C++ mode, parse "::" like ": :". + if (AteExtraColon) + AteExtraColon = false; + else { + AteExtraColon = Tok.is(tok::coloncolon); + ConsumeToken(); + } + + if (!AteExtraColon && + ParseAsmOperandsOpt(Names, Constraints, Exprs)) + return StmtError(); + } + + assert(Names.size() == Constraints.size() && + Constraints.size() == Exprs.size() && + "Input operand size mismatch!"); + + unsigned NumInputs = Names.size() - NumOutputs; + + // Parse the clobbers, if present. + if (AteExtraColon || Tok.is(tok::colon)) { + if (!AteExtraColon) + ConsumeToken(); + + // Parse the asm-string list for clobbers if present. + if (Tok.isNot(tok::r_paren)) { + while (1) { + ExprResult Clobber(ParseAsmStringLiteral()); + + if (Clobber.isInvalid()) + break; + + Clobbers.push_back(Clobber.release()); + + if (Tok.isNot(tok::comma)) break; + ConsumeToken(); + } + } + } + + T.consumeClose(); + return Actions.ActOnGCCAsmStmt(AsmLoc, false, isVolatile, NumOutputs, + NumInputs, Names.data(), Constraints, Exprs, + AsmString.take(), Clobbers, + T.getCloseLocation()); +} + +/// ParseAsmOperands - Parse the asm-operands production as used by +/// asm-statement, assuming the leading ':' token was eaten. +/// +/// [GNU] asm-operands: +/// asm-operand +/// asm-operands ',' asm-operand +/// +/// [GNU] asm-operand: +/// asm-string-literal '(' expression ')' +/// '[' identifier ']' asm-string-literal '(' expression ')' +/// +// +// FIXME: Avoid unnecessary std::string trashing. +bool Parser::ParseAsmOperandsOpt(SmallVectorImpl<IdentifierInfo *> &Names, + SmallVectorImpl<Expr *> &Constraints, + SmallVectorImpl<Expr *> &Exprs) { + // 'asm-operands' isn't present? + if (!isTokenStringLiteral() && Tok.isNot(tok::l_square)) + return false; + + while (1) { + // Read the [id] if present. + if (Tok.is(tok::l_square)) { + BalancedDelimiterTracker T(*this, tok::l_square); + T.consumeOpen(); + + if (Tok.isNot(tok::identifier)) { + Diag(Tok, diag::err_expected_ident); + SkipUntil(tok::r_paren, StopAtSemi); + return true; + } + + IdentifierInfo *II = Tok.getIdentifierInfo(); + ConsumeToken(); + + Names.push_back(II); + T.consumeClose(); + } else + Names.push_back(0); + + ExprResult Constraint(ParseAsmStringLiteral()); + if (Constraint.isInvalid()) { + SkipUntil(tok::r_paren, StopAtSemi); + return true; + } + Constraints.push_back(Constraint.release()); + + if (Tok.isNot(tok::l_paren)) { + Diag(Tok, diag::err_expected_lparen_after) << "asm operand"; + SkipUntil(tok::r_paren, StopAtSemi); + return true; + } + + // Read the parenthesized expression. + BalancedDelimiterTracker T(*this, tok::l_paren); + T.consumeOpen(); + ExprResult Res(ParseExpression()); + T.consumeClose(); + if (Res.isInvalid()) { + SkipUntil(tok::r_paren, StopAtSemi); + return true; + } + Exprs.push_back(Res.release()); + // Eat the comma and continue parsing if it exists. + if (Tok.isNot(tok::comma)) return false; + ConsumeToken(); + } +} + +Decl *Parser::ParseFunctionStatementBody(Decl *Decl, ParseScope &BodyScope) { + assert(Tok.is(tok::l_brace)); + SourceLocation LBraceLoc = Tok.getLocation(); + + if (SkipFunctionBodies && (!Decl || Actions.canSkipFunctionBody(Decl)) && + trySkippingFunctionBody()) { + BodyScope.Exit(); + return Actions.ActOnSkippedFunctionBody(Decl); + } + + PrettyDeclStackTraceEntry CrashInfo(Actions, Decl, LBraceLoc, + "parsing function body"); + + // Do not enter a scope for the brace, as the arguments are in the same scope + // (the function body) as the body itself. Instead, just read the statement + // list and put it into a CompoundStmt for safe keeping. + StmtResult FnBody(ParseCompoundStatementBody()); + + // If the function body could not be parsed, make a bogus compoundstmt. + if (FnBody.isInvalid()) { + Sema::CompoundScopeRAII CompoundScope(Actions); + FnBody = Actions.ActOnCompoundStmt(LBraceLoc, LBraceLoc, None, false); + } + + BodyScope.Exit(); + return Actions.ActOnFinishFunctionBody(Decl, FnBody.take()); +} + +/// ParseFunctionTryBlock - Parse a C++ function-try-block. +/// +/// function-try-block: +/// 'try' ctor-initializer[opt] compound-statement handler-seq +/// +Decl *Parser::ParseFunctionTryBlock(Decl *Decl, ParseScope &BodyScope) { + assert(Tok.is(tok::kw_try) && "Expected 'try'"); + SourceLocation TryLoc = ConsumeToken(); + + PrettyDeclStackTraceEntry CrashInfo(Actions, Decl, TryLoc, + "parsing function try block"); + + // Constructor initializer list? + if (Tok.is(tok::colon)) + ParseConstructorInitializer(Decl); + else + Actions.ActOnDefaultCtorInitializers(Decl); + + if (SkipFunctionBodies && Actions.canSkipFunctionBody(Decl) && + trySkippingFunctionBody()) { + BodyScope.Exit(); + return Actions.ActOnSkippedFunctionBody(Decl); + } + + SourceLocation LBraceLoc = Tok.getLocation(); + StmtResult FnBody(ParseCXXTryBlockCommon(TryLoc, /*FnTry*/true)); + // If we failed to parse the try-catch, we just give the function an empty + // compound statement as the body. + if (FnBody.isInvalid()) { + Sema::CompoundScopeRAII CompoundScope(Actions); + FnBody = Actions.ActOnCompoundStmt(LBraceLoc, LBraceLoc, None, false); + } + + BodyScope.Exit(); + return Actions.ActOnFinishFunctionBody(Decl, FnBody.take()); +} + +bool Parser::trySkippingFunctionBody() { + assert(Tok.is(tok::l_brace)); + assert(SkipFunctionBodies && + "Should only be called when SkipFunctionBodies is enabled"); + + if (!PP.isCodeCompletionEnabled()) { + ConsumeBrace(); + SkipUntil(tok::r_brace); + return true; + } + + // We're in code-completion mode. Skip parsing for all function bodies unless + // the body contains the code-completion point. + TentativeParsingAction PA(*this); + ConsumeBrace(); + if (SkipUntil(tok::r_brace, StopAtCodeCompletion)) { + PA.Commit(); + return true; + } + + PA.Revert(); + return false; +} + +/// ParseCXXTryBlock - Parse a C++ try-block. +/// +/// try-block: +/// 'try' compound-statement handler-seq +/// +StmtResult Parser::ParseCXXTryBlock() { + assert(Tok.is(tok::kw_try) && "Expected 'try'"); + + SourceLocation TryLoc = ConsumeToken(); + return ParseCXXTryBlockCommon(TryLoc); +} + +/// ParseCXXTryBlockCommon - Parse the common part of try-block and +/// function-try-block. +/// +/// try-block: +/// 'try' compound-statement handler-seq +/// +/// function-try-block: +/// 'try' ctor-initializer[opt] compound-statement handler-seq +/// +/// handler-seq: +/// handler handler-seq[opt] +/// +/// [Borland] try-block: +/// 'try' compound-statement seh-except-block +/// 'try' compound-statment seh-finally-block +/// +StmtResult Parser::ParseCXXTryBlockCommon(SourceLocation TryLoc, bool FnTry) { + if (Tok.isNot(tok::l_brace)) + return StmtError(Diag(Tok, diag::err_expected_lbrace)); + // FIXME: Possible draft standard bug: attribute-specifier should be allowed? + + StmtResult TryBlock(ParseCompoundStatement(/*isStmtExpr=*/false, + Scope::DeclScope | Scope::TryScope | + (FnTry ? Scope::FnTryCatchScope : 0))); + if (TryBlock.isInvalid()) + return TryBlock; + + // Borland allows SEH-handlers with 'try' + + if ((Tok.is(tok::identifier) && + Tok.getIdentifierInfo() == getSEHExceptKeyword()) || + Tok.is(tok::kw___finally)) { + // TODO: Factor into common return ParseSEHHandlerCommon(...) + StmtResult Handler; + if(Tok.getIdentifierInfo() == getSEHExceptKeyword()) { + SourceLocation Loc = ConsumeToken(); + Handler = ParseSEHExceptBlock(Loc); + } + else { + SourceLocation Loc = ConsumeToken(); + Handler = ParseSEHFinallyBlock(Loc); + } + if(Handler.isInvalid()) + return Handler; + + return Actions.ActOnSEHTryBlock(true /* IsCXXTry */, + TryLoc, + TryBlock.take(), + Handler.take()); + } + else { + StmtVector Handlers; + + // C++11 attributes can't appear here, despite this context seeming + // statement-like. + DiagnoseAndSkipCXX11Attributes(); + + if (Tok.isNot(tok::kw_catch)) + return StmtError(Diag(Tok, diag::err_expected_catch)); + while (Tok.is(tok::kw_catch)) { + StmtResult Handler(ParseCXXCatchBlock(FnTry)); + if (!Handler.isInvalid()) + Handlers.push_back(Handler.release()); + } + // Don't bother creating the full statement if we don't have any usable + // handlers. + if (Handlers.empty()) + return StmtError(); + + return Actions.ActOnCXXTryBlock(TryLoc, TryBlock.take(), Handlers); + } +} + +/// ParseCXXCatchBlock - Parse a C++ catch block, called handler in the standard +/// +/// handler: +/// 'catch' '(' exception-declaration ')' compound-statement +/// +/// exception-declaration: +/// attribute-specifier-seq[opt] type-specifier-seq declarator +/// attribute-specifier-seq[opt] type-specifier-seq abstract-declarator[opt] +/// '...' +/// +StmtResult Parser::ParseCXXCatchBlock(bool FnCatch) { + assert(Tok.is(tok::kw_catch) && "Expected 'catch'"); + + SourceLocation CatchLoc = ConsumeToken(); + + BalancedDelimiterTracker T(*this, tok::l_paren); + if (T.expectAndConsume(diag::err_expected_lparen)) + return StmtError(); + + // C++ 3.3.2p3: + // The name in a catch exception-declaration is local to the handler and + // shall not be redeclared in the outermost block of the handler. + ParseScope CatchScope(this, Scope::DeclScope | Scope::ControlScope | + (FnCatch ? Scope::FnTryCatchScope : 0)); + + // exception-declaration is equivalent to '...' or a parameter-declaration + // without default arguments. + Decl *ExceptionDecl = 0; + if (Tok.isNot(tok::ellipsis)) { + ParsedAttributesWithRange Attributes(AttrFactory); + MaybeParseCXX11Attributes(Attributes); + + DeclSpec DS(AttrFactory); + DS.takeAttributesFrom(Attributes); + + if (ParseCXXTypeSpecifierSeq(DS)) + return StmtError(); + + Declarator ExDecl(DS, Declarator::CXXCatchContext); + ParseDeclarator(ExDecl); + ExceptionDecl = Actions.ActOnExceptionDeclarator(getCurScope(), ExDecl); + } else + ConsumeToken(); + + T.consumeClose(); + if (T.getCloseLocation().isInvalid()) + return StmtError(); + + if (Tok.isNot(tok::l_brace)) + return StmtError(Diag(Tok, diag::err_expected_lbrace)); + + // FIXME: Possible draft standard bug: attribute-specifier should be allowed? + StmtResult Block(ParseCompoundStatement()); + if (Block.isInvalid()) + return Block; + + return Actions.ActOnCXXCatchBlock(CatchLoc, ExceptionDecl, Block.take()); +} + +void Parser::ParseMicrosoftIfExistsStatement(StmtVector &Stmts) { + IfExistsCondition Result; + if (ParseMicrosoftIfExistsCondition(Result)) + return; + + // Handle dependent statements by parsing the braces as a compound statement. + // This is not the same behavior as Visual C++, which don't treat this as a + // compound statement, but for Clang's type checking we can't have anything + // inside these braces escaping to the surrounding code. + if (Result.Behavior == IEB_Dependent) { + if (!Tok.is(tok::l_brace)) { + Diag(Tok, diag::err_expected_lbrace); + return; + } + + StmtResult Compound = ParseCompoundStatement(); + if (Compound.isInvalid()) + return; + + StmtResult DepResult = Actions.ActOnMSDependentExistsStmt(Result.KeywordLoc, + Result.IsIfExists, + Result.SS, + Result.Name, + Compound.get()); + if (DepResult.isUsable()) + Stmts.push_back(DepResult.get()); + return; + } + + BalancedDelimiterTracker Braces(*this, tok::l_brace); + if (Braces.consumeOpen()) { + Diag(Tok, diag::err_expected_lbrace); + return; + } + + switch (Result.Behavior) { + case IEB_Parse: + // Parse the statements below. + break; + + case IEB_Dependent: + llvm_unreachable("Dependent case handled above"); + + case IEB_Skip: + Braces.skipToEnd(); + return; + } + + // Condition is true, parse the statements. + while (Tok.isNot(tok::r_brace)) { + StmtResult R = ParseStatementOrDeclaration(Stmts, false); + if (R.isUsable()) + Stmts.push_back(R.release()); + } + Braces.consumeClose(); +}