path: root/include/clang/Parse/Parser.h

//===--- Parser.h - C Language Parser ---------------------------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
//  This file defines the Parser interface.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_CLANG_PARSE_PARSER_H
#define LLVM_CLANG_PARSE_PARSER_H

#include "clang/Lex/Preprocessor.h"
#include "clang/Parse/Action.h"
#include "clang/Parse/DeclSpec.h"
#include <stack>

namespace clang {
  class AttributeList;
  class DeclSpec;
  class Declarator;
  class FieldDeclarator;
  class ObjCDeclSpec;
  class PragmaHandler;
  class Scope;
  class DiagnosticBuilder;

/// Parser - This implements a parser for the C family of languages.  After
/// parsing units of the grammar, productions are invoked to handle whatever has
/// been read.
///
class Parser {
  Preprocessor &PP;
  
  /// Tok - The current token we are peeking ahead.  All parsing methods assume
  /// that this is valid.
  Token Tok;
  
  unsigned short ParenCount, BracketCount, BraceCount;

  /// Actions - These are the callbacks we invoke as we parse various constructs
  /// in the file.  This refers to the common base class between MinimalActions
  /// and SemaActions for those uses that don't matter.
  Action &Actions;
  
  Scope *CurScope;
  Diagnostic &Diags;
  
  /// ScopeCache - Cache scopes to reduce malloc traffic.
  enum { ScopeCacheSize = 16 };
  unsigned NumCachedScopes;
  Scope *ScopeCache[ScopeCacheSize];

  /// Ident_super - IdentifierInfo for "super", to support fast
  /// comparison.
  IdentifierInfo *Ident_super;

  PragmaHandler *PackHandler;

public:
  Parser(Preprocessor &PP, Action &Actions);
  ~Parser();

  const LangOptions &getLang() const { return PP.getLangOptions(); }
  TargetInfo &getTargetInfo() const { return PP.getTargetInfo(); }
  Action &getActions() const { return Actions; }
  
  // Type forwarding.  All of these are statically 'void*', but they may all be
  // different actual classes based on the actions in place.
  typedef Action::ExprTy ExprTy;
  typedef Action::StmtTy StmtTy;
  typedef Action::DeclTy DeclTy;
  typedef Action::TypeTy TypeTy;
  typedef Action::BaseTy BaseTy;
  typedef Action::MemInitTy MemInitTy;
  typedef Action::CXXScopeTy CXXScopeTy;
  typedef Action::TemplateParamsTy TemplateParamsTy;
  typedef Action::TemplateArgTy TemplateArgTy;

  typedef llvm::SmallVector<TemplateParamsTy *, 4> TemplateParameterLists;

  typedef Action::ExprResult        ExprResult;
  typedef Action::StmtResult        StmtResult;
  typedef Action::BaseResult        BaseResult;
  typedef Action::MemInitResult     MemInitResult;

  typedef Action::OwningExprResult OwningExprResult;
  typedef Action::OwningStmtResult OwningStmtResult;
  typedef Action::OwningTemplateArgResult OwningTemplateArgResult;

  typedef Action::ExprArg ExprArg;
  typedef Action::MultiStmtArg MultiStmtArg;

  /// Adorns a ExprResult with Actions to make it an OwningExprResult
  OwningExprResult Owned(ExprResult res) {
    return OwningExprResult(Actions, res);
  }
  /// Adorns a StmtResult with Actions to make it an OwningStmtResult
  OwningStmtResult Owned(StmtResult res) {
    return OwningStmtResult(Actions, res);
  }

  OwningExprResult ExprError() { return OwningExprResult(Actions, true); }
  OwningStmtResult StmtError() { return OwningStmtResult(Actions, true); }
  OwningTemplateArgResult TemplateArgError() { 
    return OwningTemplateArgResult(Actions, true); 
  }

  OwningExprResult ExprError(const DiagnosticBuilder &) { return ExprError(); }
  OwningStmtResult StmtError(const DiagnosticBuilder &) { return StmtError(); }
  OwningTemplateArgResult TemplateArgError(const DiagnosticBuilder &) {
    return TemplateArgError();
  }

  // Parsing methods.
  
  /// ParseTranslationUnit - All in one method that initializes parses, and
  /// shuts down the parser.
  void ParseTranslationUnit();
  
  /// Initialize - Warm up the parser.
  ///
  void Initialize();
  
  /// ParseTopLevelDecl - Parse one top-level declaration. Returns true if 
  /// the EOF was encountered.
  bool ParseTopLevelDecl(DeclTy*& Result);
  
private:
  //===--------------------------------------------------------------------===//
  // Low-Level token peeking and consumption methods.
  //
  
  /// isTokenParen - Return true if the cur token is '(' or ')'.
  bool isTokenParen() const {
    return Tok.getKind() == tok::l_paren || Tok.getKind() == tok::r_paren;
  }
  /// isTokenBracket - Return true if the cur token is '[' or ']'.
  bool isTokenBracket() const {
    return Tok.getKind() == tok::l_square || Tok.getKind() == tok::r_square;
  }
  /// isTokenBrace - Return true if the cur token is '{' or '}'.
  bool isTokenBrace() const {
    return Tok.getKind() == tok::l_brace || Tok.getKind() == tok::r_brace;
  }
  
  //