Allow to override Asan shadow offset.
[gcc.git] / 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) 2002-2014 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 "tree.h" /* Required by langhooks.h. */
28 #include "predict.h"
29 #include "vec.h"
30 #include "hashtab.h"
31 #include "hash-set.h"
32 #include "machmode.h"
33 #include "tm.h"
34 #include "hard-reg-set.h"
35 #include "input.h"
36 #include "function.h"
37 #include "basic-block.h"
38 #include "tree-ssa-alias.h"
39 #include "internal-fn.h"
40 #include "gimple-expr.h"
41 #include "is-a.h"
42 #include "gimple.h"
43 #include "langhooks.h"
44 #include "rtl.h"
45 #include "dbgcnt.h"
46 #include "debug.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 unrecognised -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 \"%s\"", 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 }
261
262 /* Decode command-line options to an array, like
263 decode_cmdline_options_to_array and with the same arguments but
264 using the default lang_mask. */
265
266 void
267 decode_cmdline_options_to_array_default_mask (unsigned int argc,
268 const char **argv,
269 struct cl_decoded_option **decoded_options,
270 unsigned int *decoded_options_count)
271 {
272 decode_cmdline_options_to_array (argc, argv,
273 initial_lang_mask | CL_COMMON | CL_TARGET,
274 decoded_options, decoded_options_count);
275 }
276
277 /* Set *HANDLERS to the default set of option handlers for use in the
278 compilers proper (not the driver). */
279 void
280 set_default_handlers (struct cl_option_handlers *handlers)
281 {
282 handlers->unknown_option_callback = unknown_option_callback;
283 handlers->wrong_lang_callback = complain_wrong_lang;
284 handlers->num_handlers = 3;
285 handlers->handlers[0].handler = lang_handle_option;
286 handlers->handlers[0].mask = initial_lang_mask;
287 handlers->handlers[1].handler = common_handle_option;
288 handlers->handlers[1].mask = CL_COMMON;
289 handlers->handlers[2].handler = target_handle_option;
290 handlers->handlers[2].mask = CL_TARGET;
291 }
292
293 /* Parse command line options and set default flag values. Do minimal
294 options processing. The decoded options are in *DECODED_OPTIONS
295 and *DECODED_OPTIONS_COUNT; settings go in OPTS, OPTS_SET and DC;
296 the options are located at LOC. */
297 void
298 decode_options (struct gcc_options *opts, struct gcc_options *opts_set,
299 struct cl_decoded_option *decoded_options,
300 unsigned int decoded_options_count,
301 location_t loc, diagnostic_context *dc)
302 {
303 struct cl_option_handlers handlers;
304
305 unsigned int lang_mask;
306
307 lang_mask = initial_lang_mask;
308
309 set_default_handlers (&handlers);
310
311 default_options_optimization (opts, opts_set,
312 decoded_options, decoded_options_count,
313 loc, lang_mask, &handlers, dc);
314
315 read_cmdline_options (opts, opts_set,
316 decoded_options, decoded_options_count,
317 loc, lang_mask,
318 &handlers, dc);
319
320 finish_options (opts, opts_set, loc);
321 }
322
323 /* Process common options that have been deferred until after the
324 handlers have been called for all options. */
325
326 void
327 handle_common_deferred_options (void)
328 {
329 unsigned int i;
330 cl_deferred_option *opt;
331 vec<cl_deferred_option> v;
332
333 if (common_deferred_options)
334 v = *((vec<cl_deferred_option> *) common_deferred_options);
335 else
336 v = vNULL;
337
338 if (flag_dump_all_passed)
339 enable_rtl_dump_file ();
340
341 if (flag_opt_info)
342 opt_info_switch_p (NULL);
343
344 FOR_EACH_VEC_ELT (v, i, opt)
345 {
346 switch (opt->opt_index)
347 {
348 case OPT_fcall_used_:
349 fix_register (opt->arg, 0, 1);
350 break;
351
352 case OPT_fcall_saved_:
353 fix_register (opt->arg, 0, 0);
354 break;
355
356 case OPT_fdbg_cnt_:
357 dbg_cnt_process_opt (opt->arg);
358 break;
359
360 case OPT_fdbg_cnt_list:
361 dbg_cnt_list_all_counters ();
362 break;
363
364 case OPT_fdebug_prefix_map_:
365 add_debug_prefix_map (opt->arg);
366 break;
367
368 case OPT_fdump_:
369 if (!g->get_dumps ()->dump_switch_p (opt->arg))
370 error ("unrecognized command line option %<-fdump-%s%>", opt->arg);
371 break;
372
373 case OPT_fopt_info_:
374 if (!opt_info_switch_p (opt->arg))
375 error ("unrecognized command line option %<-fopt-info-%s%>",
376 opt->arg);
377 break;
378
379 case OPT_fenable_:
380 case OPT_fdisable_:
381 if (opt->opt_index == OPT_fenable_)
382 enable_pass (opt->arg);
383 else
384 disable_pass (opt->arg);
385 break;
386
387 case OPT_ffixed_:
388 /* Deferred. */
389 fix_register (opt->arg, 1, 1);
390 break;
391
392 case OPT_fplugin_:
393 #ifdef ENABLE_PLUGIN
394 add_new_plugin (opt->arg);
395 #else
396 error ("plugin support is disabled; configure with --enable-plugin");
397 #endif
398 break;
399
400 case OPT_fplugin_arg_:
401 #ifdef ENABLE_PLUGIN
402 parse_plugin_arg_opt (opt->arg);
403 #else
404 error ("plugin support is disabled; configure with --enable-plugin");
405 #endif
406 break;
407
408 case OPT_frandom_seed:
409 /* The real switch is -fno-random-seed. */
410 if (!opt->value)
411 set_random_seed (NULL);
412 break;
413
414 case OPT_frandom_seed_:
415 set_random_seed (opt->arg);
416 break;
417
418 case OPT_fstack_limit:
419 /* The real switch is -fno-stack-limit. */
420 if (!opt->value)
421 stack_limit_rtx = NULL_RTX;
422 break;
423
424 case OPT_fstack_limit_register_:
425 {
426 int reg = decode_reg_name (opt->arg);
427 if (reg < 0)
428 error ("unrecognized register name %qs", opt->arg);
429 else
430 stack_limit_rtx = gen_rtx_REG (Pmode, reg);
431 }
432 break;
433
434 case OPT_fstack_limit_symbol_:
435 stack_limit_rtx = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (opt->arg));
436 break;
437
438 case OPT_fasan_shadow_offset_:
439 if (!(flag_sanitize & SANITIZE_KERNEL_ADDRESS))
440 error ("-fasan-shadow-offset should only be used "
441 "with -fsanitize=kernel-address");
442 if (!set_asan_shadow_offset (opt->arg))
443 error ("unrecognized shadow offset %qs", opt->arg);
444 break;
445
446 default:
447 gcc_unreachable ();
448 }
449 }
450 }