gcc/go/gofrontend/go.cc

   1 // go.cc -- Go frontend main file for gcc.
   2
   3 // Copyright 2009 The Go Authors. All rights reserved.
   4 // Use of this source code is governed by a BSD-style
   5 // license that can be found in the LICENSE file.
   6
   7 #include "go-system.h"
   8
   9 #include "go-c.h"
  10 #include "go-diagnostics.h"
  11
  12 #include "lex.h"
  13 #include "parse.h"
  14 #include "backend.h"
  15 #include "gogo.h"
  16
  17 // The data structures we build to represent the file.
  18 static Gogo* gogo;
  19
  20 // Create the main IR data structure.
  21
  22 GO_EXTERN_C
  23 void
  24 go_create_gogo(const struct go_create_gogo_args* args)
  25 {
  26   go_assert(::gogo == NULL);
  27   ::gogo = new Gogo(args->backend, args->linemap, args->int_type_size,
  28                     args->pointer_size);
  29
  30   if (args->pkgpath != NULL)
  31     ::gogo->set_pkgpath(args->pkgpath);
  32   else if (args->prefix != NULL)
  33     ::gogo->set_prefix(args->prefix);
  34
  35   if (args->relative_import_path != NULL)
  36     ::gogo->set_relative_import_path(args->relative_import_path);
  37   ::gogo->set_check_divide_by_zero(args->check_divide_by_zero);
  38   ::gogo->set_check_divide_overflow(args->check_divide_overflow);
  39   if (args->compiling_runtime)
  40     ::gogo->set_compiling_runtime(args->compiling_runtime);
  41   if (args->c_header != NULL)
  42     ::gogo->set_c_header(args->c_header);
  43   ::gogo->set_debug_escape_level(args->debug_escape_level);
  44   if (args->debug_escape_hash != NULL)
  45     ::gogo->set_debug_escape_hash(args->debug_escape_hash);
  46   ::gogo->set_nil_check_size_threshold(args->nil_check_size_threshold);
  47   if (args->debug_optimization)
  48     ::gogo->set_debug_optimization(args->debug_optimization);
  49   if (args->need_eqtype)
  50     ::gogo->set_need_eqtype(args->need_eqtype);
  51 }
  52
  53 // Parse the input files.
  54
  55 GO_EXTERN_C
  56 void
  57 go_parse_input_files(const char** filenames, unsigned int filename_count,
  58                      bool only_check_syntax, bool)
  59 {
  60   go_assert(filename_count > 0);
  61
  62   Lex::Linknames all_linknames;
  63   for (unsigned int i = 0; i < filename_count; ++i)
  64     {
  65       if (i > 0)
  66         ::gogo->clear_file_scope();
  67
  68       const char* filename = filenames[i];
  69       FILE* file;
  70       if (strcmp(filename, "-") == 0)
  71         file = stdin;
  72       else
  73         {
  74           file = fopen(filename, "r");
  75           if (file == NULL)
  76             go_fatal_error(Linemap::unknown_location(),
  77                            "cannot open %s: %m", filename);
  78         }
  79
  80       Lex lexer(filename, file, ::gogo->linemap());
  81
  82       Parse parse(&lexer, ::gogo);
  83       parse.program();
  84
  85       if (strcmp(filename, "-") != 0)
  86         fclose(file);
  87
  88       Lex::Linknames* linknames = lexer.get_and_clear_linknames();
  89       if (linknames != NULL)
  90         {
  91           if (!::gogo->current_file_imported_unsafe())
  92             {
  93               for (Lex::Linknames::const_iterator p = linknames->begin();
  94                    p != linknames->end();
  95                    ++p)
  96                 go_error_at(p->second.loc,
  97                             ("%<//go:linkname%> only allowed in Go files that "
  98                              "import \"unsafe\""));
  99             }
 100           all_linknames.insert(linknames->begin(), linknames->end());
 101         }
 102     }
 103
 104   ::gogo->clear_file_scope();
 105
 106   // If the global predeclared names are referenced but not defined,
 107   // define them now.
 108   ::gogo->define_global_names();
 109
 110   // Apply any go:linkname directives.
 111   for (Lex::Linknames::const_iterator p = all_linknames.begin();
 112        p != all_linknames.end();
 113        ++p)
 114     ::gogo->add_linkname(p->first, p->second.is_exported, p->second.ext_name,
 115                          p->second.loc);
 116
 117   // Finalize method lists and build stub methods for named types.
 118   ::gogo->finalize_methods();
 119
 120   // Check that functions have a terminating statement.
 121   ::gogo->check_return_statements();
 122
 123   // Now that we have seen all the names, lower the parse tree into a
 124   // form which is easier to use.
 125   ::gogo->lower_parse_tree();
 126
 127   // At this point we have handled all inline functions, so we no
 128   // longer need the linemap.
 129   ::gogo->linemap()->stop();
 130
 131   // Create function descriptors as needed.
 132   ::gogo->create_function_descriptors();
 133
 134   // Now that we have seen all the names, verify that types are
 135   // correct.
 136   ::gogo->verify_types();
 137
 138   // Work out types of unspecified constants and variables.
 139   ::gogo->determine_types();
 140
 141   // Check types and issue errors as appropriate.
 142   ::gogo->check_types();
 143
 144   if (only_check_syntax)
 145     return;
 146
 147   // Do simple deadcode elimination.
 148   ::gogo->remove_deadcode();
 149
 150   // Make implicit type conversions explicit.
 151   ::gogo->add_conversions();
 152
 153   // Analyze the program flow for escape information.
 154   ::gogo->analyze_escape();
 155
 156   // Export global identifiers as appropriate.
 157   ::gogo->do_exports();
 158
 159   // Use temporary variables to force order of evaluation.
 160   ::gogo->order_evaluations();
 161
 162   // Turn short-cut operators (&&, ||) into explicit if statements.
 163   ::gogo->remove_shortcuts();
 164
 165   // Convert named types to backend representation.
 166   ::gogo->convert_named_types();
 167
 168   // Build thunks for functions which call recover.
 169   ::gogo->build_recover_thunks();
 170
 171   // Convert complicated go and defer statements into simpler ones.
 172   ::gogo->simplify_thunk_statements();
 173
 174   // Write out queued up functions for hash and comparison of types.
 175   ::gogo->write_specific_type_functions();
 176
 177   // Add write barriers.
 178   ::gogo->add_write_barriers();
 179
 180   // Flatten the parse tree.
 181   ::gogo->flatten();
 182
 183   // Reclaim memory of escape analysis Nodes.
 184   ::gogo->reclaim_escape_nodes();
 185
 186   // Dump ast, use filename[0] as the base name
 187   ::gogo->dump_ast(filenames[0]);
 188 }
 189
 190 // Write out globals.
 191
 192 GO_EXTERN_C
 193 void
 194 go_write_globals()
 195 {
 196   return ::gogo->write_globals();
 197 }
 198
 199 // Return the global IR structure.  This is used by some of the
 200 // langhooks to pass to other code.
 201
 202 Gogo*
 203 go_get_gogo()
 204 {
 205   return ::gogo;
 206 }