gcc/opts-global.c

   1 /* Command line option handling.  Code involving global state that
   2    should not be shared with the driver.
   3    Copyright (C) 2002-2015 Free Software Foundation, Inc.
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 3, or (at your option) any later
  10 version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING3.  If not see
  19 <http://www.gnu.org/licenses/>.  */
  20
  21 #include "config.h"
  22 #include "system.h"
  23 #include "coretypes.h"
  24 #include "diagnostic.h"
  25 #include "opts.h"
  26 #include "flags.h"
  27 #include "alias.h"
  28 #include "symtab.h"
  29 #include "tree.h" /* Required by langhooks.h.  */
  30 #include "fold-const.h"
  31 #include "predict.h"
  32 #include "tm.h"
  33 #include "hard-reg-set.h"
  34 #include "function.h"
  35 #include "basic-block.h"
  36 #include "tree-ssa-alias.h"
  37 #include "internal-fn.h"
  38 #include "gimple-expr.h"
  39 #include "gimple.h"
  40 #include "langhooks.h"
  41 #include "rtl.h"
  42 #include "dbgcnt.h"
  43 #include "debug.h"
  44 #include "plugin-api.h"
  45 #include "ipa-ref.h"
  46 #include "cgraph.h"
  47 #include "lto-streamer.h"
  48 #include "output.h"
  49 #include "plugin.h"
  50 #include "toplev.h"
  51 #include "tree-pass.h"
  52 #include "context.h"
  53 #include "asan.h"
  54
  55 typedef const char *const_char_p; /* For DEF_VEC_P.  */
  56
  57 static vec<const_char_p> ignored_options;
  58
  59 /* Input file names.  */
  60 const char **in_fnames;
  61 unsigned num_in_fnames;
  62
  63 /* Return a malloced slash-separated list of languages in MASK.  */
  64
  65 static char *
  66 write_langs (unsigned int mask)
  67 {
  68   unsigned int n = 0, len = 0;
  69   const char *lang_name;
  70   char *result;
  71
  72   for (n = 0; (lang_name = lang_names[n]) != 0; n++)
  73     if (mask & (1U << n))
  74       len += strlen (lang_name) + 1;
  75
  76   result = XNEWVEC (char, len);
  77   len = 0;
  78   for (n = 0; (lang_name = lang_names[n]) != 0; n++)
  79     if (mask & (1U << n))
  80       {
  81         if (len)
  82           result[len++] = '/';
  83         strcpy (result + len, lang_name);
  84         len += strlen (lang_name);
  85       }
  86
  87   result[len] = 0;
  88
  89   return result;
  90 }
  91
  92 /* Complain that switch DECODED does not apply to this front end (mask
  93    LANG_MASK).  */
  94
  95 static void
  96 complain_wrong_lang (const struct cl_decoded_option *decoded,
  97                      unsigned int lang_mask)
  98 {
  99   const struct cl_option *option = &cl_options[decoded->opt_index];
 100   const char *text = decoded->orig_option_with_args_text;
 101   char *ok_langs = NULL, *bad_lang = NULL;
 102   unsigned int opt_flags = option->flags;
 103
 104   if (!lang_hooks.complain_wrong_lang_p (option))
 105     return;
 106
 107   opt_flags &= ((1U << cl_lang_count) - 1) | CL_DRIVER;
 108   if (opt_flags != CL_DRIVER)
 109     ok_langs = write_langs (opt_flags);
 110   if (lang_mask != CL_DRIVER)
 111     bad_lang = write_langs (lang_mask);
 112
 113   if (opt_flags == CL_DRIVER)
 114     error ("command line option %qs is valid for the driver but not for %s",
 115            text, bad_lang);
 116   else if (lang_mask == CL_DRIVER)
 117     gcc_unreachable ();
 118   else
 119     /* Eventually this should become a hard error IMO.  */
 120     warning (0, "command line option %qs is valid for %s but not for %s",
 121              text, ok_langs, bad_lang);
 122
 123   free (ok_langs);
 124   free (bad_lang);
 125 }
 126
 127 /* Buffer the unknown option described by the string OPT.  Currently,
 128    we only complain about unknown -Wno-* options if they may have
 129    prevented a diagnostic. Otherwise, we just ignore them.  Note that
 130    if we do complain, it is only as a warning, not an error; passing
 131    the compiler an unrecognized -Wno-* option should never change
 132    whether the compilation succeeds or fails.  */
 133
 134 static void
 135 postpone_unknown_option_warning (const char *opt)
 136 {
 137   ignored_options.safe_push (opt);
 138 }
 139
 140 /* Produce a warning for each option previously buffered.  */
 141
 142 void
 143 print_ignored_options (void)
 144 {
 145   while (!ignored_options.is_empty ())
 146     {
 147       const char *opt;
 148
 149       opt = ignored_options.pop ();
 150       warning_at (UNKNOWN_LOCATION, 0,
 151                   "unrecognized command line option %qs", opt);
 152     }
 153 }
 154
 155 /* Handle an unknown option DECODED, returning true if an error should
 156    be given.  */
 157
 158 static bool
 159 unknown_option_callback (const struct cl_decoded_option *decoded)
 160 {
 161   const char *opt = decoded->arg;
 162
 163   if (opt[1] == 'W' && opt[2] == 'n' && opt[3] == 'o' && opt[4] == '-'
 164       && !(decoded->errors & CL_ERR_NEGATIVE))
 165     {
 166       /* We don't generate warnings for unknown -Wno-* options unless
 167          we issue diagnostics.  */
 168       postpone_unknown_option_warning (opt);
 169       return false;
 170     }
 171   else
 172     return true;
 173 }
 174
 175 /* Handle a front-end option; arguments and return value as for
 176    handle_option.  */
 177
 178 static bool
 179 lang_handle_option (struct gcc_options *opts,
 180                     struct gcc_options *opts_set,
 181                     const struct cl_decoded_option *decoded,
 182                     unsigned int lang_mask ATTRIBUTE_UNUSED, int kind,
 183                     location_t loc,
 184                     const struct cl_option_handlers *handlers,
 185                     diagnostic_context *dc)
 186 {
 187   gcc_assert (opts == &global_options);
 188   gcc_assert (opts_set == &global_options_set);
 189   gcc_assert (dc == global_dc);
 190   gcc_assert (decoded->canonical_option_num_elements <= 2);
 191   return lang_hooks.handle_option (decoded->opt_index, decoded->arg,
 192                                    decoded->value, kind, loc, handlers);
 193 }
 194
 195 /* Handle FILENAME from the command line.  */
 196
 197 static void
 198 add_input_filename (const char *filename)
 199 {
 200   num_in_fnames++;
 201   in_fnames = XRESIZEVEC (const char *, in_fnames, num_in_fnames);
 202   in_fnames[num_in_fnames - 1] = filename;
 203 }
 204
 205 /* Handle the vector of command line options (located at LOC), storing
 206    the results of processing DECODED_OPTIONS and DECODED_OPTIONS_COUNT
 207    in OPTS and OPTS_SET and using DC for diagnostic state.  LANG_MASK
 208    contains has a single bit set representing the current language.
 209    HANDLERS describes what functions to call for the options.  */
 210
 211 static void
 212 read_cmdline_options (struct gcc_options *opts, struct gcc_options *opts_set,
 213                       struct cl_decoded_option *decoded_options,
 214                       unsigned int decoded_options_count,
 215                       location_t loc,
 216                       unsigned int lang_mask,
 217                       const struct cl_option_handlers *handlers,
 218                       diagnostic_context *dc)
 219 {
 220   unsigned int i;
 221
 222   for (i = 1; i < decoded_options_count; i++)
 223     {
 224       if (decoded_options[i].opt_index == OPT_SPECIAL_input_file)
 225         {
 226           /* Input files should only ever appear on the main command
 227              line.  */
 228           gcc_assert (opts == &global_options);
 229           gcc_assert (opts_set == &global_options_set);
 230
 231           if (opts->x_main_input_filename == NULL)
 232             {
 233               opts->x_main_input_filename = decoded_options[i].arg;
 234               opts->x_main_input_baselength
 235                 = base_of_path (opts->x_main_input_filename,
 236                                 &opts->x_main_input_basename);
 237             }
 238           add_input_filename (decoded_options[i].arg);
 239           continue;
 240         }
 241
 242       read_cmdline_option (opts, opts_set,
 243                            decoded_options + i, loc, lang_mask, handlers,
 244                            dc);
 245     }
 246 }
 247
 248 /* Language mask determined at initialization.  */
 249 static unsigned int initial_lang_mask;
 250
 251 /* Initialize global options-related settings at start-up.  */
 252
 253 void
 254 init_options_once (void)
 255 {
 256   /* Perform language-specific options initialization.  */
 257   initial_lang_mask = lang_hooks.option_lang_mask ();
 258
 259   lang_hooks.initialize_diagnostics (global_dc);
 260   /* ??? Ideally, we should do this earlier and the FEs will override
 261      it if desired (none do it so far).  However, the way the FEs
 262      construct their pretty-printers means that all previous settings
 263      are overriden.  */
 264   diagnostic_color_init (global_dc);
 265 }
 266
 267 /* Decode command-line options to an array, like
 268    decode_cmdline_options_to_array and with the same arguments but
 269    using the default lang_mask.  */
 270
 271 void
 272 decode_cmdline_options_to_array_default_mask (unsigned int argc,
 273                                               const char **argv,
 274                                               struct cl_decoded_option **decoded_options,
 275                                               unsigned int *decoded_options_count)
 276 {
 277   decode_cmdline_options_to_array (argc, argv,
 278                                    initial_lang_mask | CL_COMMON | CL_TARGET,
 279                                    decoded_options, decoded_options_count);
 280 }
 281
 282 /* Set *HANDLERS to the default set of option handlers for use in the
 283    compilers proper (not the driver).  */
 284 void
 285 set_default_handlers (struct cl_option_handlers *handlers)
 286 {
 287   handlers->unknown_option_callback = unknown_option_callback;
 288   handlers->wrong_lang_callback = complain_wrong_lang;
 289   handlers->num_handlers = 3;
 290   handlers->handlers[0].handler = lang_handle_option;
 291   handlers->handlers[0].mask = initial_lang_mask;
 292   handlers->handlers[1].handler = common_handle_option;
 293   handlers->handlers[1].mask = CL_COMMON;
 294   handlers->handlers[2].handler = target_handle_option;
 295   handlers->handlers[2].mask = CL_TARGET;
 296 }
 297
 298 /* Parse command line options and set default flag values.  Do minimal
 299    options processing.  The decoded options are in *DECODED_OPTIONS
 300    and *DECODED_OPTIONS_COUNT; settings go in OPTS, OPTS_SET and DC;
 301    the options are located at LOC.  */
 302 void
 303 decode_options (struct gcc_options *opts, struct gcc_options *opts_set,
 304                 struct cl_decoded_option *decoded_options,
 305                 unsigned int decoded_options_count,
 306                 location_t loc, diagnostic_context *dc)
 307 {
 308   struct cl_option_handlers handlers;
 309
 310   unsigned int lang_mask;
 311
 312   lang_mask = initial_lang_mask;
 313
 314   set_default_handlers (&handlers);
 315
 316   default_options_optimization (opts, opts_set,
 317                                 decoded_options, decoded_options_count,
 318                                 loc, lang_mask, &handlers, dc);
 319
 320   read_cmdline_options (opts, opts_set,
 321                         decoded_options, decoded_options_count,
 322                         loc, lang_mask,
 323                         &handlers, dc);
 324
 325   finish_options (opts, opts_set, loc);
 326 }
 327
 328 /* Process common options that have been deferred until after the
 329    handlers have been called for all options.  */
 330
 331 void
 332 handle_common_deferred_options (void)
 333 {
 334   unsigned int i;
 335   cl_deferred_option *opt;
 336   vec<cl_deferred_option> v;
 337
 338   if (common_deferred_options)
 339     v = *((vec<cl_deferred_option> *) common_deferred_options);
 340   else
 341     v = vNULL;
 342
 343   if (flag_dump_all_passed)
 344     enable_rtl_dump_file ();
 345
 346   if (flag_opt_info)
 347     opt_info_switch_p (NULL);
 348
 349   FOR_EACH_VEC_ELT (v, i, opt)
 350     {
 351       switch (opt->opt_index)
 352         {
 353         case OPT_fcall_used_:
 354           fix_register (opt->arg, 0, 1);
 355           break;
 356
 357         case OPT_fcall_saved_:
 358           fix_register (opt->arg, 0, 0);
 359           break;
 360
 361         case OPT_fdbg_cnt_:
 362           dbg_cnt_process_opt (opt->arg);
 363           break;
 364
 365         case OPT_fdbg_cnt_list:
 366           dbg_cnt_list_all_counters ();
 367           break;
 368
 369         case OPT_fdebug_prefix_map_:
 370           add_debug_prefix_map (opt->arg);
 371           break;
 372
 373         case OPT_fdump_:
 374           if (!g->get_dumps ()->dump_switch_p (opt->arg))
 375             error ("unrecognized command line option %<-fdump-%s%>", opt->arg);
 376           break;
 377
 378         case OPT_fopt_info_:
 379           if (!opt_info_switch_p (opt->arg))
 380             error ("unrecognized command line option %<-fopt-info-%s%>",
 381                    opt->arg);
 382           break;
 383
 384         case OPT_fenable_:
 385         case OPT_fdisable_:
 386           if (opt->opt_index == OPT_fenable_)
 387             enable_pass (opt->arg);
 388           else
 389             disable_pass (opt->arg);
 390           break;
 391
 392         case OPT_ffixed_:
 393           /* Deferred.  */
 394           fix_register (opt->arg, 1, 1);
 395           break;
 396
 397         case OPT_fplugin_:
 398 #ifdef ENABLE_PLUGIN
 399           add_new_plugin (opt->arg);
 400 #else
 401           error ("plugin support is disabled; configure with --enable-plugin");
 402 #endif
 403           break;
 404
 405         case OPT_fplugin_arg_:
 406 #ifdef ENABLE_PLUGIN
 407           parse_plugin_arg_opt (opt->arg);
 408 #else
 409           error ("plugin support is disabled; configure with --enable-plugin");
 410 #endif
 411           break;
 412
 413         case OPT_frandom_seed:
 414           /* The real switch is -fno-random-seed.  */
 415           if (!opt->value)
 416             set_random_seed (NULL);
 417           break;
 418
 419         case OPT_frandom_seed_:
 420           set_random_seed (opt->arg);
 421           break;
 422
 423         case OPT_fstack_limit:
 424           /* The real switch is -fno-stack-limit.  */
 425           if (!opt->value)
 426             stack_limit_rtx = NULL_RTX;
 427           break;
 428
 429         case OPT_fstack_limit_register_:
 430           {
 431             int reg = decode_reg_name (opt->arg);
 432             if (reg < 0)
 433               error ("unrecognized register name %qs", opt->arg);
 434             else
 435               stack_limit_rtx = gen_rtx_REG (Pmode, reg);
 436           }
 437           break;
 438
 439         case OPT_fstack_limit_symbol_:
 440           stack_limit_rtx = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (opt->arg));
 441           break;
 442
 443         case OPT_fasan_shadow_offset_:
 444           if (!(flag_sanitize & SANITIZE_KERNEL_ADDRESS))
 445             error ("-fasan-shadow-offset should only be used "
 446                    "with -fsanitize=kernel-address");
 447           if (!set_asan_shadow_offset (opt->arg))
 448              error ("unrecognized shadow offset %qs", opt->arg);
 449           break;
 450
 451         case OPT_fsanitize_sections_:
 452           set_sanitized_sections (opt->arg);
 453           break;
 454
 455         default:
 456           gcc_unreachable ();
 457         }
 458     }
 459 }