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