// go.cc -- Go frontend main file for gcc.

// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

#include "go-system.h"

#include "go-c.h"

#include "lex.h"
#include "parse.h"
#include "backend.h"
#include "gogo.h"

// The data structures we build to represent the file.
static Gogo* gogo;

// Create the main IR data structure.

GO_EXTERN_C
void
go_create_gogo(int int_type_size, int pointer_size, const char *pkgpath,
	       const char *prefix, const char *relative_import_path,
	       bool check_divide_by_zero, bool check_divide_overflow)
{
  go_assert(::gogo == NULL);
  Linemap* linemap = go_get_linemap();
  ::gogo = new Gogo(go_get_backend(), linemap, int_type_size, pointer_size);

  if (pkgpath != NULL)
    ::gogo->set_pkgpath(pkgpath);
  else if (prefix != NULL)
    ::gogo->set_prefix(prefix);

  if (relative_import_path != NULL)
    ::gogo->set_relative_import_path(relative_import_path);
  if (check_divide_by_zero)
    ::gogo->set_check_divide_by_zero(check_divide_by_zero);
  if (check_divide_overflow)
    ::gogo->set_check_divide_overflow(check_divide_overflow);
}

// Parse the input files.

GO_EXTERN_C
void
go_parse_input_files(const char** filenames, unsigned int filename_count,
		     bool only_check_syntax, bool)
{
  go_assert(filename_count > 0);

  for (unsigned int i = 0; i < filename_count; ++i)
    {
      if (i > 0)
	::gogo->clear_file_scope();

      const char* filename = filenames[i];
      FILE* file;
      if (strcmp(filename, "-") == 0)
	file = stdin;
      else
	{
	  file = fopen(filename, "r");
	  if (file == NULL)
	    fatal_error(Linemap::unknown_location(),
			"cannot open %s: %m", filename);
	}

      Lex lexer(filename, file, ::gogo->linemap());

      Parse parse(&lexer, ::gogo);
      parse.program();

      if (strcmp(filename, "-") != 0)
	fclose(file);
    }

  ::gogo->linemap()->stop();

  ::gogo->clear_file_scope();

  // If the global predeclared names are referenced but not defined,
  // define them now.
  ::gogo->define_global_names();

  // Finalize method lists and build stub methods for named types.
  ::gogo->finalize_methods();

  // Check that functions have a terminating statement.
  ::gogo->check_return_statements();

  // Now that we have seen all the names, lower the parse tree into a
  // form which is easier to use.
  ::gogo->lower_parse_tree();

  // Create function descriptors as needed.
  ::gogo->create_function_descriptors();

  // Now that we have seen all the names, verify that types are
  // correct.
  ::gogo->verify_types();

  // Work out types of unspecified constants and variables.
  ::gogo->determine_types();

  // Check types and issue errors as appropriate.
  ::gogo->check_types();

  if (only_check_syntax)
    return;

  // Export global identifiers as appropriate.
  ::gogo->do_exports();

  // Turn short-cut operators (&&, ||) into explicit if statements.
  ::gogo->remove_shortcuts();

  // Use temporary variables to force order of evaluation.
  ::gogo->order_evaluations();

  // Convert named types to backend representation.
  ::gogo->convert_named_types();

  // Build thunks for functions which call recover.
  ::gogo->build_recover_thunks();

  // Convert complicated go and defer statements into simpler ones.
  ::gogo->simplify_thunk_statements();

  // Write out queued up functions for hash and comparison of types.
  ::gogo->write_specific_type_functions();

  // Flatten the parse tree.
  ::gogo->flatten();

  // Dump ast, use filename[0] as the base name
  ::gogo->dump_ast(filenames[0]);
}

// Write out globals.

GO_EXTERN_C
void
go_write_globals()
{
  return ::gogo->write_globals();
}

// Return the global IR structure.  This is used by some of the
// langhooks to pass to other code.

Gogo*
go_get_gogo()
{
  return ::gogo;
}