1 /* Command line option handling.  Code involving global state that
2    should not be shared with the driver.
3    Copyright (C) 2002-2013 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 "ggc.h"
28 #include "tree.h" /* Required by langhooks.h.  */
29 #include "langhooks.h"
30 #include "tm.h" /* Required by rtl.h.  */
31 #include "rtl.h"
32 #include "dbgcnt.h"
33 #include "debug.h"
34 #include "lto-streamer.h"
35 #include "output.h"
36 #include "plugin.h"
37 #include "toplev.h"
38 #include "tree-pass.h"
39 
40 typedef const char *const_char_p; /* For DEF_VEC_P.  */
41 
42 static vec<const_char_p> ignored_options;
43 
44 /* Input file names.  */
45 const char **in_fnames;
46 unsigned num_in_fnames;
47 
48 /* Return a malloced slash-separated list of languages in MASK.  */
49 
50 static char *
write_langs(unsigned int mask)51 write_langs (unsigned int mask)
52 {
53   unsigned int n = 0, len = 0;
54   const char *lang_name;
55   char *result;
56 
57   for (n = 0; (lang_name = lang_names[n]) != 0; n++)
58     if (mask & (1U << n))
59       len += strlen (lang_name) + 1;
60 
61   result = XNEWVEC (char, len);
62   len = 0;
63   for (n = 0; (lang_name = lang_names[n]) != 0; n++)
64     if (mask & (1U << n))
65       {
66 	if (len)
67 	  result[len++] = '/';
68 	strcpy (result + len, lang_name);
69 	len += strlen (lang_name);
70       }
71 
72   result[len] = 0;
73 
74   return result;
75 }
76 
77 /* Complain that switch DECODED does not apply to this front end (mask
78    LANG_MASK).  */
79 
80 static void
complain_wrong_lang(const struct cl_decoded_option * decoded,unsigned int lang_mask)81 complain_wrong_lang (const struct cl_decoded_option *decoded,
82 		     unsigned int lang_mask)
83 {
84   const struct cl_option *option = &cl_options[decoded->opt_index];
85   const char *text = decoded->orig_option_with_args_text;
86   char *ok_langs = NULL, *bad_lang = NULL;
87   unsigned int opt_flags = option->flags;
88 
89   if (!lang_hooks.complain_wrong_lang_p (option))
90     return;
91 
92   opt_flags &= ((1U << cl_lang_count) - 1) | CL_DRIVER;
93   if (opt_flags != CL_DRIVER)
94     ok_langs = write_langs (opt_flags);
95   if (lang_mask != CL_DRIVER)
96     bad_lang = write_langs (lang_mask);
97 
98   if (opt_flags == CL_DRIVER)
99     error ("command line option %qs is valid for the driver but not for %s",
100 	   text, bad_lang);
101   else if (lang_mask == CL_DRIVER)
102     gcc_unreachable ();
103   else
104     /* Eventually this should become a hard error IMO.  */
105     warning (0, "command line option %qs is valid for %s but not for %s",
106 	     text, ok_langs, bad_lang);
107 
108   free (ok_langs);
109   free (bad_lang);
110 }
111 
112 /* Buffer the unknown option described by the string OPT.  Currently,
113    we only complain about unknown -Wno-* options if they may have
114    prevented a diagnostic. Otherwise, we just ignore them.  Note that
115    if we do complain, it is only as a warning, not an error; passing
116    the compiler an unrecognised -Wno-* option should never change
117    whether the compilation succeeds or fails.  */
118 
119 static void
postpone_unknown_option_warning(const char * opt)120 postpone_unknown_option_warning (const char *opt)
121 {
122   ignored_options.safe_push (opt);
123 }
124 
125 /* Produce a warning for each option previously buffered.  */
126 
127 void
print_ignored_options(void)128 print_ignored_options (void)
129 {
130   while (!ignored_options.is_empty ())
131     {
132       const char *opt;
133 
134       opt = ignored_options.pop ();
135       warning_at (UNKNOWN_LOCATION, 0,
136 		  "unrecognized command line option \"%s\"", opt);
137     }
138 }
139 
140 /* Handle an unknown option DECODED, returning true if an error should
141    be given.  */
142 
143 static bool
unknown_option_callback(const struct cl_decoded_option * decoded)144 unknown_option_callback (const struct cl_decoded_option *decoded)
145 {
146   const char *opt = decoded->arg;
147 
148   if (opt[1] == 'W' && opt[2] == 'n' && opt[3] == 'o' && opt[4] == '-'
149       && !(decoded->errors & CL_ERR_NEGATIVE))
150     {
151       /* We don't generate warnings for unknown -Wno-* options unless
152 	 we issue diagnostics.  */
153       postpone_unknown_option_warning (opt);
154       return false;
155     }
156   else
157     return true;
158 }
159 
160 /* Handle a front-end option; arguments and return value as for
161    handle_option.  */
162 
163 static bool
lang_handle_option(struct gcc_options * opts,struct gcc_options * opts_set,const struct cl_decoded_option * decoded,unsigned int lang_mask ATTRIBUTE_UNUSED,int kind,location_t loc,const struct cl_option_handlers * handlers,diagnostic_context * dc)164 lang_handle_option (struct gcc_options *opts,
165 		    struct gcc_options *opts_set,
166 		    const struct cl_decoded_option *decoded,
167 		    unsigned int lang_mask ATTRIBUTE_UNUSED, int kind,
168 		    location_t loc,
169 		    const struct cl_option_handlers *handlers,
170 		    diagnostic_context *dc)
171 {
172   gcc_assert (opts == &global_options);
173   gcc_assert (opts_set == &global_options_set);
174   gcc_assert (dc == global_dc);
175   gcc_assert (decoded->canonical_option_num_elements <= 2);
176   return lang_hooks.handle_option (decoded->opt_index, decoded->arg,
177 				   decoded->value, kind, loc, handlers);
178 }
179 
180 /* Handle FILENAME from the command line.  */
181 
182 static void
add_input_filename(const char * filename)183 add_input_filename (const char *filename)
184 {
185   num_in_fnames++;
186   in_fnames = XRESIZEVEC (const char *, in_fnames, num_in_fnames);
187   in_fnames[num_in_fnames - 1] = filename;
188 }
189 
190 /* Handle the vector of command line options (located at LOC), storing
191    the results of processing DECODED_OPTIONS and DECODED_OPTIONS_COUNT
192    in OPTS and OPTS_SET and using DC for diagnostic state.  LANG_MASK
193    contains has a single bit set representing the current language.
194    HANDLERS describes what functions to call for the options.  */
195 
196 static void
read_cmdline_options(struct gcc_options * opts,struct gcc_options * opts_set,struct cl_decoded_option * decoded_options,unsigned int decoded_options_count,location_t loc,unsigned int lang_mask,const struct cl_option_handlers * handlers,diagnostic_context * dc)197 read_cmdline_options (struct gcc_options *opts, struct gcc_options *opts_set,
198 		      struct cl_decoded_option *decoded_options,
199 		      unsigned int decoded_options_count,
200 		      location_t loc,
201 		      unsigned int lang_mask,
202 		      const struct cl_option_handlers *handlers,
203 		      diagnostic_context *dc)
204 {
205   unsigned int i;
206 
207   for (i = 1; i < decoded_options_count; i++)
208     {
209       if (decoded_options[i].opt_index == OPT_SPECIAL_input_file)
210 	{
211 	  /* Input files should only ever appear on the main command
212 	     line.  */
213 	  gcc_assert (opts == &global_options);
214 	  gcc_assert (opts_set == &global_options_set);
215 
216 	  if (opts->x_main_input_filename == NULL)
217 	    {
218 	      opts->x_main_input_filename = decoded_options[i].arg;
219 	      opts->x_main_input_baselength
220 		= base_of_path (opts->x_main_input_filename,
221 				&opts->x_main_input_basename);
222 	    }
223 	  add_input_filename (decoded_options[i].arg);
224 	  continue;
225 	}
226 
227       read_cmdline_option (opts, opts_set,
228 			   decoded_options + i, loc, lang_mask, handlers,
229 			   dc);
230     }
231 }
232 
233 /* Handle -ftree-vectorizer-verbose=ARG by remapping it to -fopt-info.
234    It remaps the old verbosity values as following:
235 
236    REPORT_NONE ==> No dump is output
237    REPORT_VECTORIZED_LOCATIONS ==> "-optimized"
238    REPORT_UNVECTORIZED_LOCATIONS ==> "-missed"
239 
240    Any higher verbosity levels get mapped to "-all" flags.  */
241 
242 static void
dump_remap_tree_vectorizer_verbose(const char * arg)243 dump_remap_tree_vectorizer_verbose (const char *arg)
244 {
245   int value = atoi (arg);
246   const char *remapped_opt_info = NULL;
247 
248   switch (value)
249     {
250     case 0:
251       break;
252     case 1:
253       remapped_opt_info = "optimized";
254       break;
255     case 2:
256       remapped_opt_info = "missed";
257       break;
258     default:
259       remapped_opt_info = "all";
260       break;
261     }
262 
263   if (remapped_opt_info)
264     opt_info_switch_p (remapped_opt_info);
265 }
266 
267 /* Language mask determined at initialization.  */
268 static unsigned int initial_lang_mask;
269 
270 /* Initialize global options-related settings at start-up.  */
271 
272 void
init_options_once(void)273 init_options_once (void)
274 {
275   /* Perform language-specific options initialization.  */
276   initial_lang_mask = lang_hooks.option_lang_mask ();
277 
278   lang_hooks.initialize_diagnostics (global_dc);
279 }
280 
281 /* Decode command-line options to an array, like
282    decode_cmdline_options_to_array and with the same arguments but
283    using the default lang_mask.  */
284 
285 void
decode_cmdline_options_to_array_default_mask(unsigned int argc,const char ** argv,struct cl_decoded_option ** decoded_options,unsigned int * decoded_options_count)286 decode_cmdline_options_to_array_default_mask (unsigned int argc,
287 					      const char **argv,
288 					      struct cl_decoded_option **decoded_options,
289 					      unsigned int *decoded_options_count)
290 {
291   decode_cmdline_options_to_array (argc, argv,
292 				   initial_lang_mask | CL_COMMON | CL_TARGET,
293 				   decoded_options, decoded_options_count);
294 }
295 
296 /* Set *HANDLERS to the default set of option handlers for use in the
297    compilers proper (not the driver).  */
298 void
set_default_handlers(struct cl_option_handlers * handlers)299 set_default_handlers (struct cl_option_handlers *handlers)
300 {
301   handlers->unknown_option_callback = unknown_option_callback;
302   handlers->wrong_lang_callback = complain_wrong_lang;
303   handlers->num_handlers = 3;
304   handlers->handlers[0].handler = lang_handle_option;
305   handlers->handlers[0].mask = initial_lang_mask;
306   handlers->handlers[1].handler = common_handle_option;
307   handlers->handlers[1].mask = CL_COMMON;
308   handlers->handlers[2].handler = target_handle_option;
309   handlers->handlers[2].mask = CL_TARGET;
310 }
311 
312 /* Parse command line options and set default flag values.  Do minimal
313    options processing.  The decoded options are in *DECODED_OPTIONS
314    and *DECODED_OPTIONS_COUNT; settings go in OPTS, OPTS_SET and DC;
315    the options are located at LOC.  */
316 void
decode_options(struct gcc_options * opts,struct gcc_options * opts_set,struct cl_decoded_option * decoded_options,unsigned int decoded_options_count,location_t loc,diagnostic_context * dc)317 decode_options (struct gcc_options *opts, struct gcc_options *opts_set,
318 		struct cl_decoded_option *decoded_options,
319 		unsigned int decoded_options_count,
320 		location_t loc, diagnostic_context *dc)
321 {
322   struct cl_option_handlers handlers;
323 
324   unsigned int lang_mask;
325 
326   lang_mask = initial_lang_mask;
327 
328   set_default_handlers (&handlers);
329 
330   default_options_optimization (opts, opts_set,
331 				decoded_options, decoded_options_count,
332 				loc, lang_mask, &handlers, dc);
333 
334   read_cmdline_options (opts, opts_set,
335 			decoded_options, decoded_options_count,
336 			loc, lang_mask,
337 			&handlers, dc);
338 
339   finish_options (opts, opts_set, loc);
340 }
341 
342 /* Process common options that have been deferred until after the
343    handlers have been called for all options.  */
344 
345 void
handle_common_deferred_options(void)346 handle_common_deferred_options (void)
347 {
348   unsigned int i;
349   cl_deferred_option *opt;
350   vec<cl_deferred_option> v;
351 
352   if (common_deferred_options)
353     v = *((vec<cl_deferred_option> *) common_deferred_options);
354   else
355     v = vNULL;
356 
357   if (flag_dump_all_passed)
358     enable_rtl_dump_file ();
359 
360   if (flag_opt_info)
361     opt_info_switch_p (NULL);
362 
363   FOR_EACH_VEC_ELT (v, i, opt)
364     {
365       switch (opt->opt_index)
366 	{
367 	case OPT_fcall_used_:
368 	  fix_register (opt->arg, 0, 1);
369 	  break;
370 
371 	case OPT_fcall_saved_:
372 	  fix_register (opt->arg, 0, 0);
373 	  break;
374 
375 	case OPT_fdbg_cnt_:
376 	  dbg_cnt_process_opt (opt->arg);
377 	  break;
378 
379 	case OPT_fdbg_cnt_list:
380 	  dbg_cnt_list_all_counters ();
381 	  break;
382 
383 	case OPT_fdebug_prefix_map_:
384 	  add_debug_prefix_map (opt->arg);
385 	  break;
386 
387 	case OPT_fdump_:
388 	  if (!dump_switch_p (opt->arg))
389 	    error ("unrecognized command line option %<-fdump-%s%>", opt->arg);
390 	  break;
391 
392         case OPT_fopt_info_:
393 	  if (!opt_info_switch_p (opt->arg))
394 	    error ("unrecognized command line option %<-fopt-info-%s%>",
395                    opt->arg);
396           break;
397 
398 	case OPT_fenable_:
399 	case OPT_fdisable_:
400 	  if (opt->opt_index == OPT_fenable_)
401 	    enable_pass (opt->arg);
402           else
403 	    disable_pass (opt->arg);
404           break;
405 
406 	case OPT_ffixed_:
407 	  /* Deferred.  */
408 	  fix_register (opt->arg, 1, 1);
409 	  break;
410 
411 	case OPT_fplugin_:
412 #ifdef ENABLE_PLUGIN
413 	  add_new_plugin (opt->arg);
414 #else
415 	  error ("plugin support is disabled; configure with --enable-plugin");
416 #endif
417 	  break;
418 
419 	case OPT_fplugin_arg_:
420 #ifdef ENABLE_PLUGIN
421 	  parse_plugin_arg_opt (opt->arg);
422 #else
423 	  error ("plugin support is disabled; configure with --enable-plugin");
424 #endif
425 	  break;
426 
427 	case OPT_frandom_seed:
428 	  /* The real switch is -fno-random-seed.  */
429 	  if (!opt->value)
430 	    set_random_seed (NULL);
431 	  break;
432 
433 	case OPT_frandom_seed_:
434 	  set_random_seed (opt->arg);
435 	  break;
436 
437 	case OPT_fstack_limit:
438 	  /* The real switch is -fno-stack-limit.  */
439 	  if (!opt->value)
440 	    stack_limit_rtx = NULL_RTX;
441 	  break;
442 
443 	case OPT_fstack_limit_register_:
444 	  {
445 	    int reg = decode_reg_name (opt->arg);
446 	    if (reg < 0)
447 	      error ("unrecognized register name %qs", opt->arg);
448 	    else
449 	      stack_limit_rtx = gen_rtx_REG (Pmode, reg);
450 	  }
451 	  break;
452 
453 	case OPT_fstack_limit_symbol_:
454 	  stack_limit_rtx = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (opt->arg));
455 	  break;
456 
457         case OPT_ftree_vectorizer_verbose_:
458 	  dump_remap_tree_vectorizer_verbose (opt->arg);
459           break;
460 
461 	default:
462 	  gcc_unreachable ();
463 	}
464     }
465 }
466