lib/Parse/ParseAST.cpp

//===--- ParseAST.cpp - Provide the clang::ParseAST method ----------------===//
//
//                     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 clang::ParseAST method.
//
//===----------------------------------------------------------------------===//

#include "clang/Parse/ParseAST.h"
#include "clang/Sema/Sema.h"
#include "clang/Sema/CodeCompleteConsumer.h"
#include "clang/Sema/SemaConsumer.h"
#include "clang/Sema/ExternalSemaSource.h"
#include "clang/AST/ASTConsumer.h"
#include "clang/AST/DeclCXX.h"
#include "clang/AST/ExternalASTSource.h"
#include "clang/AST/Stmt.h"
#include "clang/Parse/Parser.h"
#include "llvm/ADT/OwningPtr.h"
#include "llvm/Support/CrashRecoveryContext.h"
#include <cstdio>

using namespace clang;

//===----------------------------------------------------------------------===//
// Public interface to the file
//===----------------------------------------------------------------------===//

/// ParseAST - Parse the entire file specified, notifying the ASTConsumer as
/// the file is parsed.  This inserts the parsed decls into the translation unit
/// held by Ctx.
///
void clang::ParseAST(Preprocessor &PP, ASTConsumer *Consumer,
                     ASTContext &Ctx, bool PrintStats,
                     TranslationUnitKind TUKind,
                     CodeCompleteConsumer *CompletionConsumer) {

  OwningPtr<Sema> S(new Sema(PP, Ctx, *Consumer,
                                   TUKind,
                                   CompletionConsumer));

  // Recover resources if we crash before exiting this method.
  llvm::CrashRecoveryContextCleanupRegistrar<Sema> CleaupSema(S.get());
  
  ParseAST(*S.get(), PrintStats);
}

void clang::ParseAST(Sema &S, bool PrintStats) {
  // Collect global stats on Decls/Stmts (until we have a module streamer).
  if (PrintStats) {
    Decl::CollectingStats(true);
    Stmt::CollectingStats(true);
  }

  // Also turn on collection of stats inside of the Sema object.
  bool OldCollectStats = PrintStats;
  std::swap(OldCollectStats, S.CollectStats);

  ASTConsumer *Consumer = &S.getASTConsumer();

  OwningPtr<Parser> ParseOP(new Parser(S.getPreprocessor(), S));
  Parser &P = *ParseOP.get();

  PrettyStackTraceParserEntry CrashInfo(P);

  // Recover resources if we crash before exiting this method.
  llvm::CrashRecoveryContextCleanupRegistrar<Parser>
    CleaupParser(ParseOP.get());

  S.getPreprocessor().EnterMainSourceFile();
  P.Initialize();
  S.Initialize();
  
  if (ExternalASTSource *External = S.getASTContext().getExternalSource())
    External->StartTranslationUnit(Consumer);
  
  bool Abort = false;
  Parser::DeclGroupPtrTy ADecl;
  
  while (!P.ParseTopLevelDecl(ADecl)) {  // Not end of file.
    // If we got a null return and something *was* parsed, ignore it.  This
    // is due to a top-level semicolon, an action override, or a parse error
    // skipping something.
    if (ADecl) {
      if (!Consumer->HandleTopLevelDecl(ADecl.get())) {
        Abort = true;
        break;
      }
    }
  };

  if (Abort)
    return;
  
  // Process any TopLevelDecls generated by #pragma weak.
  for (SmallVector<Decl*,2>::iterator
       I = S.WeakTopLevelDecls().begin(),
       E = S.WeakTopLevelDecls().end(); I != E; ++I)
    Consumer->HandleTopLevelDecl(DeclGroupRef(*I));
  
  Consumer->HandleTranslationUnit(S.getASTContext());

  std::swap(OldCollectStats, S.CollectStats);
  if (PrintStats) {
    llvm::errs() << "\nSTATISTICS:\n";
    P.getActions().PrintStats();
    S.getASTContext().PrintStats();
    Decl::PrintStats();
    Stmt::PrintStats();
    Consumer->PrintStats();
  }
}