gcc/plugin.c

   1 /* Support for GCC plugin mechanism.
   2    Copyright (C) 2009-2013 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 3, or (at your option)
   9 any later version.
  10
  11 GCC is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GCC; see the file COPYING3.  If not see
  18 <http://www.gnu.org/licenses/>.  */
  19
  20 /* This file contains the support for GCC plugin mechanism based on the
  21    APIs described in doc/plugin.texi.  */
  22
  23 #include "config.h"
  24 #include "system.h"
  25 #include "coretypes.h"
  26 #include "hash-table.h"
  27 #include "diagnostic-core.h"
  28 #include "tree.h"
  29 #include "tree-pass.h"
  30 #include "intl.h"
  31 #include "plugin.h"
  32 #include "ggc.h"
  33
  34 #ifdef ENABLE_PLUGIN
  35 #include "plugin-version.h"
  36 #endif
  37
  38 #define GCC_PLUGIN_STRINGIFY0(X) #X
  39 #define GCC_PLUGIN_STRINGIFY1(X) GCC_PLUGIN_STRINGIFY0 (X)
  40
  41 /* Event names as strings.  Keep in sync with enum plugin_event.  */
  42 static const char *plugin_event_name_init[] =
  43 {
  44 # define DEFEVENT(NAME) GCC_PLUGIN_STRINGIFY1 (NAME),
  45 # include "plugin.def"
  46 # undef DEFEVENT
  47 };
  48
  49 /* A printf format large enough for the largest event above.  */
  50 #define FMT_FOR_PLUGIN_EVENT "%-32s"
  51
  52 const char **plugin_event_name = plugin_event_name_init;
  53
  54 /* Event hashtable helpers.  */
  55
  56 struct event_hasher : typed_noop_remove <const char *>
  57 {
  58   typedef const char *value_type;
  59   typedef const char *compare_type;
  60   static inline hashval_t hash (const value_type *);
  61   static inline bool equal (const value_type *, const compare_type *);
  62 };
  63
  64 /* Helper function for the event hash table that hashes the entry V.  */
  65
  66 inline hashval_t
  67 event_hasher::hash (const value_type *v)
  68 {
  69   return htab_hash_string (*v);
  70 }
  71
  72 /* Helper function for the event hash table that compares the name of an
  73    existing entry (S1) with the given string (S2).  */
  74
  75 inline bool
  76 event_hasher::equal (const value_type *s1, const compare_type *s2)
  77 {
  78   return !strcmp (*s1, *s2);
  79 }
  80
  81 /* A hash table to map event names to the position of the names in the
  82    plugin_event_name table.  */
  83 static hash_table <event_hasher> event_tab;
  84
  85 /* Keep track of the limit of allocated events and space ready for
  86    allocating events.  */
  87 static int event_last = PLUGIN_EVENT_FIRST_DYNAMIC;
  88 static int event_horizon = PLUGIN_EVENT_FIRST_DYNAMIC;
  89
  90 /* Hash table for the plugin_name_args objects created during command-line
  91    parsing.  */
  92 static htab_t plugin_name_args_tab = NULL;
  93
  94 /* List node for keeping track of plugin-registered callback.  */
  95 struct callback_info
  96 {
  97   const char *plugin_name;   /* Name of plugin that registers the callback.  */
  98   plugin_callback_func func; /* Callback to be called.  */
  99   void *user_data;           /* plugin-specified data.  */
 100   struct callback_info *next;
 101 };
 102
 103 /* An array of lists of 'callback_info' objects indexed by the event id.  */
 104 static struct callback_info *plugin_callbacks_init[PLUGIN_EVENT_FIRST_DYNAMIC];
 105 static struct callback_info **plugin_callbacks = plugin_callbacks_init;
 106
 107 /* For invoke_plugin_callbacks(), see plugin.h.  */
 108 bool flag_plugin_added = false;
 109
 110 #ifdef ENABLE_PLUGIN
 111 /* Each plugin should define an initialization function with exactly
 112    this name.  */
 113 static const char *str_plugin_init_func_name = "plugin_init";
 114
 115 /* Each plugin should define this symbol to assert that it is
 116    distributed under a GPL-compatible license.  */
 117 static const char *str_license = "plugin_is_GPL_compatible";
 118 #endif
 119
 120 /* Helper function for the hash table that compares the base_name of the
 121    existing entry (S1) with the given string (S2).  */
 122
 123 static int
 124 htab_str_eq (const void *s1, const void *s2)
 125 {
 126   const struct plugin_name_args *plugin = (const struct plugin_name_args *) s1;
 127   return !strcmp (plugin->base_name, (const char *) s2);
 128 }
 129
 130
 131 /* Given a plugin's full-path name FULL_NAME, e.g. /pass/to/NAME.so,
 132    return NAME.  */
 133
 134 static char *
 135 get_plugin_base_name (const char *full_name)
 136 {
 137   /* First get the base name part of the full-path name, i.e. NAME.so.  */
 138   char *base_name = xstrdup (lbasename (full_name));
 139
 140   /* Then get rid of '.so' part of the name.  */
 141   strip_off_ending (base_name, strlen (base_name));
 142
 143   return base_name;
 144 }
 145
 146
 147 /* Create a plugin_name_args object for the given plugin and insert it
 148    to the hash table. This function is called when
 149    -fplugin=/path/to/NAME.so or -fplugin=NAME option is processed.  */
 150
 151 void
 152 add_new_plugin (const char* plugin_name)
 153 {
 154   struct plugin_name_args *plugin;
 155   void **slot;
 156   char *base_name;
 157   bool name_is_short;
 158   const char *pc;
 159
 160   flag_plugin_added = true;
 161
 162   /* Replace short names by their full path when relevant.  */
 163   name_is_short  = !IS_ABSOLUTE_PATH (plugin_name);
 164   for (pc = plugin_name; name_is_short && *pc; pc++)
 165     if (*pc == '.' || IS_DIR_SEPARATOR (*pc))
 166       name_is_short = false;
 167
 168   if (name_is_short)
 169     {
 170       base_name = CONST_CAST (char*, plugin_name);
 171       /* FIXME: the ".so" suffix is currently builtin, since plugins
 172          only work on ELF host systems like e.g. Linux or Solaris.
 173          When plugins shall be available on non ELF systems such as
 174          Windows or MacOS, this code has to be greatly improved.  */
 175       plugin_name = concat (default_plugin_dir_name (), "/",
 176                             plugin_name, ".so", NULL);
 177       if (access (plugin_name, R_OK))
 178         fatal_error
 179           ("inaccessible plugin file %s expanded from short plugin name %s: %m",
 180            plugin_name, base_name);
 181     }
 182   else
 183     base_name = get_plugin_base_name (plugin_name);
 184
 185   /* If this is the first -fplugin= option we encounter, create
 186      'plugin_name_args_tab' hash table.  */
 187   if (!plugin_name_args_tab)
 188     plugin_name_args_tab = htab_create (10, htab_hash_string, htab_str_eq,
 189                                         NULL);
 190
 191   slot = htab_find_slot (plugin_name_args_tab, base_name, INSERT);
 192
 193   /* If the same plugin (name) has been specified earlier, either emit an
 194      error or a warning message depending on if they have identical full
 195      (path) names.  */
 196   if (*slot)
 197     {
 198       plugin = (struct plugin_name_args *) *slot;
 199       if (strcmp (plugin->full_name, plugin_name))
 200         error ("plugin %s was specified with different paths:\n%s\n%s",
 201                plugin->base_name, plugin->full_name, plugin_name);
 202       return;
 203     }
 204
 205   plugin = XCNEW (struct plugin_name_args);
 206   plugin->base_name = base_name;
 207   plugin->full_name = plugin_name;
 208
 209   *slot = plugin;
 210 }
 211
 212
 213 /* Parse the -fplugin-arg-<name>-<key>[=<value>] option and create a
 214    'plugin_argument' object for the parsed key-value pair. ARG is
 215    the <name>-<key>[=<value>] part of the option.  */
 216
 217 void
 218 parse_plugin_arg_opt (const char *arg)
 219 {
 220   size_t len = 0, name_len = 0, key_len = 0, value_len = 0;
 221   const char *ptr, *name_start = arg, *key_start = NULL, *value_start = NULL;
 222   char *name, *key, *value;
 223   void **slot;
 224   bool name_parsed = false, key_parsed = false;
 225
 226   /* Iterate over the ARG string and identify the starting character position
 227      of 'name', 'key', and 'value' and their lengths.  */
 228   for (ptr = arg; *ptr; ++ptr)
 229     {
 230       /* Only the first '-' encountered is considered a separator between
 231          'name' and 'key'. All the subsequent '-'s are considered part of
 232          'key'. For example, given -fplugin-arg-foo-bar-primary-key=value,
 233          the plugin name is 'foo' and the key is 'bar-primary-key'.  */
 234       if (*ptr == '-' && !name_parsed)
 235         {
 236           name_len = len;
 237           len = 0;
 238           key_start = ptr + 1;
 239           name_parsed = true;
 240           continue;
 241         }
 242       else if (*ptr == '=')
 243         {
 244           if (!key_parsed)
 245             {
 246               key_len = len;
 247               len = 0;
 248               value_start = ptr + 1;
 249               key_parsed = true;
 250             }
 251           continue;
 252         }
 253       else
 254         ++len;
 255     }
 256
 257   if (!key_start)
 258     {
 259       error ("malformed option -fplugin-arg-%s (missing -<key>[=<value>])",
 260              arg);
 261       return;
 262     }
 263
 264   /* If the option doesn't contain the 'value' part, LEN is the KEY_LEN.
 265      Otherwise, it is the VALUE_LEN.  */
 266   if (!value_start)
 267     key_len = len;
 268   else
 269     value_len = len;
 270
 271   name = XNEWVEC (char, name_len + 1);
 272   strncpy (name, name_start, name_len);
 273   name[name_len] = '\0';
 274
 275   /* Check if the named plugin has already been specified earlier in the
 276      command-line.  */
 277   if (plugin_name_args_tab
 278       && ((slot = htab_find_slot (plugin_name_args_tab, name, NO_INSERT))
 279           != NULL))
 280     {
 281       struct plugin_name_args *plugin = (struct plugin_name_args *) *slot;
 282
 283       key = XNEWVEC (char, key_len + 1);
 284       strncpy (key, key_start, key_len);
 285       key[key_len] = '\0';
 286       if (value_start)
 287         {
 288           value = XNEWVEC (char, value_len + 1);
 289           strncpy (value, value_start, value_len);
 290           value[value_len] = '\0';
 291         }
 292       else
 293         value = NULL;
 294
 295       /* Create a plugin_argument object for the parsed key-value pair.
 296          If there are already arguments for this plugin, we will need to
 297          adjust the argument array size by creating a new array and deleting
 298          the old one. If the performance ever becomes an issue, we can
 299          change the code by pre-allocating a larger array first.  */
 300       if (plugin->argc > 0)
 301         {
 302           struct plugin_argument *args = XNEWVEC (struct plugin_argument,
 303                                                   plugin->argc + 1);
 304           memcpy (args, plugin->argv,
 305                   sizeof (struct plugin_argument) * plugin->argc);
 306           XDELETEVEC (plugin->argv);
 307           plugin->argv = args;
 308           ++plugin->argc;
 309         }
 310       else
 311         {
 312           gcc_assert (plugin->argv == NULL);
 313           plugin->argv = XNEWVEC (struct plugin_argument, 1);
 314           plugin->argc = 1;
 315         }
 316
 317       plugin->argv[plugin->argc - 1].key = key;
 318       plugin->argv[plugin->argc - 1].value = value;
 319     }
 320   else
 321     error ("plugin %s should be specified before -fplugin-arg-%s "
 322            "in the command line", name, arg);
 323
 324   /* We don't need the plugin's name anymore. Just release it.  */
 325   XDELETEVEC (name);
 326 }
 327
 328 /* Register additional plugin information. NAME is the name passed to
 329    plugin_init. INFO is the information that should be registered. */
 330
 331 static void
 332 register_plugin_info (const char* name, struct plugin_info *info)
 333 {
 334   void **slot = htab_find_slot (plugin_name_args_tab, name, NO_INSERT);
 335   struct plugin_name_args *plugin = (struct plugin_name_args *) *slot;
 336   plugin->version = info->version;
 337   plugin->help = info->help;
 338 }
 339
 340 /* Look up the event id for NAME.  If the name is not found, return -1
 341    if INSERT is NO_INSERT.  */
 342
 343 int
 344 get_named_event_id (const char *name, enum insert_option insert)
 345 {
 346   const char ***slot;
 347
 348   if (!event_tab.is_created ())
 349     {
 350       int i;
 351
 352       event_tab.create (150);
 353       for (i = 0; i < event_last; i++)
 354         {
 355           slot = event_tab.find_slot (&plugin_event_name[i], INSERT);
 356           gcc_assert (*slot == HTAB_EMPTY_ENTRY);
 357           *slot = &plugin_event_name[i];
 358         }
 359     }
 360   slot = event_tab.find_slot (&name, insert);
 361   if (slot == NULL)
 362     return -1;
 363   if (*slot != HTAB_EMPTY_ENTRY)
 364     return *slot - &plugin_event_name[0];
 365
 366   if (event_last >= event_horizon)
 367     {
 368       event_horizon = event_last * 2;
 369       if (plugin_event_name == plugin_event_name_init)
 370         {
 371           plugin_event_name = XNEWVEC (const char *, event_horizon);
 372           memcpy (plugin_event_name, plugin_event_name_init,
 373                   sizeof plugin_event_name_init);
 374           plugin_callbacks = XNEWVEC (struct callback_info *, event_horizon);
 375           memcpy (plugin_callbacks, plugin_callbacks_init,
 376                   sizeof plugin_callbacks_init);
 377         }
 378       else
 379         {
 380           plugin_event_name
 381             = XRESIZEVEC (const char *, plugin_event_name, event_horizon);
 382           plugin_callbacks = XRESIZEVEC (struct callback_info *,
 383                                          plugin_callbacks, event_horizon);
 384         }
 385       /* All the pointers in the hash table will need to be updated.  */
 386       event_tab.dispose ();
 387     }
 388   else
 389     *slot = &plugin_event_name[event_last];
 390   plugin_event_name[event_last] = name;
 391   return event_last++;
 392 }
 393
 394 /* Called from the plugin's initialization code. Register a single callback.
 395    This function can be called multiple times.
 396
 397    PLUGIN_NAME - display name for this plugin
 398    EVENT       - which event the callback is for
 399    CALLBACK    - the callback to be called at the event
 400    USER_DATA   - plugin-provided data   */
 401
 402 void
 403 register_callback (const char *plugin_name,
 404                    int event,
 405                    plugin_callback_func callback,
 406                    void *user_data)
 407 {
 408   switch (event)
 409     {
 410       case PLUGIN_PASS_MANAGER_SETUP:
 411         gcc_assert (!callback);
 412         register_pass ((struct register_pass_info *) user_data);
 413         break;
 414       case PLUGIN_INFO:
 415         gcc_assert (!callback);
 416         register_plugin_info (plugin_name, (struct plugin_info *) user_data);
 417         break;
 418       case PLUGIN_REGISTER_GGC_ROOTS:
 419         gcc_assert (!callback);
 420         ggc_register_root_tab ((const struct ggc_root_tab*) user_data);
 421         break;
 422       case PLUGIN_REGISTER_GGC_CACHES:
 423         gcc_assert (!callback);
 424         ggc_register_cache_tab ((const struct ggc_cache_tab*) user_data);
 425         break;
 426       case PLUGIN_EVENT_FIRST_DYNAMIC:
 427       default:
 428         if (event < PLUGIN_EVENT_FIRST_DYNAMIC || event >= event_last)
 429           {
 430             error ("unknown callback event registered by plugin %s",
 431                    plugin_name);
 432             return;
 433           }
 434       /* Fall through.  */
 435       case PLUGIN_FINISH_TYPE:
 436       case PLUGIN_FINISH_DECL:
 437       case PLUGIN_START_UNIT:
 438       case PLUGIN_FINISH_UNIT:
 439       case PLUGIN_PRE_GENERICIZE:
 440       case PLUGIN_GGC_START:
 441       case PLUGIN_GGC_MARKING:
 442       case PLUGIN_GGC_END:
 443       case PLUGIN_ATTRIBUTES:
 444       case PLUGIN_PRAGMAS:
 445       case PLUGIN_FINISH:
 446       case PLUGIN_ALL_PASSES_START:
 447       case PLUGIN_ALL_PASSES_END:
 448       case PLUGIN_ALL_IPA_PASSES_START:
 449       case PLUGIN_ALL_IPA_PASSES_END:
 450       case PLUGIN_OVERRIDE_GATE:
 451       case PLUGIN_PASS_EXECUTION:
 452       case PLUGIN_EARLY_GIMPLE_PASSES_START:
 453       case PLUGIN_EARLY_GIMPLE_PASSES_END:
 454       case PLUGIN_NEW_PASS:
 455         {
 456           struct callback_info *new_callback;
 457           if (!callback)
 458             {
 459               error ("plugin %s registered a null callback function "
 460                      "for event %s", plugin_name, plugin_event_name[event]);
 461               return;
 462             }
 463           new_callback = XNEW (struct callback_info);
 464           new_callback->plugin_name = plugin_name;
 465           new_callback->func = callback;
 466           new_callback->user_data = user_data;
 467           new_callback->next = plugin_callbacks[event];
 468           plugin_callbacks[event] = new_callback;
 469         }
 470         break;
 471     }
 472 }
 473
 474 /* Remove a callback for EVENT which has been registered with for a plugin
 475    PLUGIN_NAME.  Return PLUGEVT_SUCCESS if a matching callback was
 476    found & removed, PLUGEVT_NO_CALLBACK if the event does not have a matching
 477    callback, and PLUGEVT_NO_SUCH_EVENT if EVENT is invalid.  */
 478 int
 479 unregister_callback (const char *plugin_name, int event)
 480 {
 481   struct callback_info *callback, **cbp;
 482
 483   if (event >= event_last)
 484     return PLUGEVT_NO_SUCH_EVENT;
 485
 486   for (cbp = &plugin_callbacks[event]; (callback = *cbp); cbp = &callback->next)
 487     if (strcmp (callback->plugin_name, plugin_name) == 0)
 488       {
 489         *cbp = callback->next;
 490         return PLUGEVT_SUCCESS;
 491       }
 492   return PLUGEVT_NO_CALLBACK;
 493 }
 494
 495 /* Invoke all plugin callbacks registered with the specified event,
 496    called from invoke_plugin_callbacks().  */
 497
 498 int
 499 invoke_plugin_callbacks_full (int event, void *gcc_data)
 500 {
 501   int retval = PLUGEVT_SUCCESS;
 502
 503   timevar_push (TV_PLUGIN_RUN);
 504
 505   switch (event)
 506     {
 507       case PLUGIN_EVENT_FIRST_DYNAMIC:
 508       default:
 509         gcc_assert (event >= PLUGIN_EVENT_FIRST_DYNAMIC);
 510         gcc_assert (event < event_last);
 511       /* Fall through.  */
 512       case PLUGIN_FINISH_TYPE:
 513       case PLUGIN_FINISH_DECL:
 514       case PLUGIN_START_UNIT:
 515       case PLUGIN_FINISH_UNIT:
 516       case PLUGIN_PRE_GENERICIZE:
 517       case PLUGIN_ATTRIBUTES:
 518       case PLUGIN_PRAGMAS:
 519       case PLUGIN_FINISH:
 520       case PLUGIN_GGC_START:
 521       case PLUGIN_GGC_MARKING:
 522       case PLUGIN_GGC_END:
 523       case PLUGIN_ALL_PASSES_START:
 524       case PLUGIN_ALL_PASSES_END:
 525       case PLUGIN_ALL_IPA_PASSES_START:
 526       case PLUGIN_ALL_IPA_PASSES_END:
 527       case PLUGIN_OVERRIDE_GATE:
 528       case PLUGIN_PASS_EXECUTION:
 529       case PLUGIN_EARLY_GIMPLE_PASSES_START:
 530       case PLUGIN_EARLY_GIMPLE_PASSES_END:
 531       case PLUGIN_NEW_PASS:
 532         {
 533           /* Iterate over every callback registered with this event and
 534              call it.  */
 535           struct callback_info *callback = plugin_callbacks[event];
 536
 537           if (!callback)
 538             retval = PLUGEVT_NO_CALLBACK;
 539           for ( ; callback; callback = callback->next)
 540             (*callback->func) (gcc_data, callback->user_data);
 541         }
 542         break;
 543
 544       case PLUGIN_PASS_MANAGER_SETUP:
 545       case PLUGIN_REGISTER_GGC_ROOTS:
 546       case PLUGIN_REGISTER_GGC_CACHES:
 547         gcc_assert (false);
 548     }
 549
 550   timevar_pop (TV_PLUGIN_RUN);
 551   return retval;
 552 }
 553
 554 #ifdef ENABLE_PLUGIN
 555 /* We need a union to cast dlsym return value to a function pointer
 556    as ISO C forbids assignment between function pointer and 'void *'.
 557    Use explicit union instead of __extension__(<union_cast>) for
 558    portability.  */
 559 #define PTR_UNION_TYPE(TOTYPE) union { void *_q; TOTYPE _nq; }
 560 #define PTR_UNION_AS_VOID_PTR(NAME) (NAME._q)
 561 #define PTR_UNION_AS_CAST_PTR(NAME) (NAME._nq)
 562
 563 /* Try to initialize PLUGIN. Return true if successful. */
 564
 565 static bool
 566 try_init_one_plugin (struct plugin_name_args *plugin)
 567 {
 568   void *dl_handle;
 569   plugin_init_func plugin_init;
 570   const char *err;
 571   PTR_UNION_TYPE (plugin_init_func) plugin_init_union;
 572
 573   /* We use RTLD_NOW to accelerate binding and detect any mismatch
 574      between the API expected by the plugin and the GCC API; we use
 575      RTLD_GLOBAL which is useful to plugins which themselves call
 576      dlopen.  */
 577   dl_handle = dlopen (plugin->full_name, RTLD_NOW | RTLD_GLOBAL);
 578   if (!dl_handle)
 579     {
 580       error ("cannot load plugin %s\n%s", plugin->full_name, dlerror ());
 581       return false;
 582     }
 583
 584   /* Clear any existing error.  */
 585   dlerror ();
 586
 587   /* Check the plugin license.  */
 588   if (dlsym (dl_handle, str_license) == NULL)
 589     fatal_error ("plugin %s is not licensed under a GPL-compatible license\n"
 590                  "%s", plugin->full_name, dlerror ());
 591
 592   PTR_UNION_AS_VOID_PTR (plugin_init_union) =
 593       dlsym (dl_handle, str_plugin_init_func_name);
 594   plugin_init = PTR_UNION_AS_CAST_PTR (plugin_init_union);
 595
 596   if ((err = dlerror ()) != NULL)
 597     {
 598       error ("cannot find %s in plugin %s\n%s", str_plugin_init_func_name,
 599              plugin->full_name, err);
 600       return false;
 601     }
 602
 603   /* Call the plugin-provided initialization routine with the arguments.  */
 604   if ((*plugin_init) (plugin, &gcc_version))
 605     {
 606       error ("fail to initialize plugin %s", plugin->full_name);
 607       return false;
 608     }
 609
 610   return true;
 611 }
 612
 613
 614 /* Routine to dlopen and initialize one plugin. This function is passed to
 615    (and called by) the hash table traverse routine. Return 1 for the
 616    htab_traverse to continue scan, 0 to stop.
 617
 618    SLOT - slot of the hash table element
 619    INFO - auxiliary pointer handed to hash table traverse routine
 620           (unused in this function)  */
 621
 622 static int
 623 init_one_plugin (void **slot, void * ARG_UNUSED (info))
 624 {
 625   struct plugin_name_args *plugin = (struct plugin_name_args *) *slot;
 626   bool ok = try_init_one_plugin (plugin);
 627   if (!ok)
 628     {
 629       htab_remove_elt (plugin_name_args_tab, plugin->base_name);
 630       XDELETE (plugin);
 631     }
 632   return 1;
 633 }
 634
 635 #endif  /* ENABLE_PLUGIN  */
 636
 637 /* Main plugin initialization function.  Called from compile_file() in
 638    toplev.c.  */
 639
 640 void
 641 initialize_plugins (void)
 642 {
 643   /* If no plugin was specified in the command-line, simply return.  */
 644   if (!plugin_name_args_tab)
 645     return;
 646
 647   timevar_push (TV_PLUGIN_INIT);
 648
 649 #ifdef ENABLE_PLUGIN
 650   /* Traverse and initialize each plugin specified in the command-line.  */
 651   htab_traverse_noresize (plugin_name_args_tab, init_one_plugin, NULL);
 652 #endif
 653
 654   timevar_pop (TV_PLUGIN_INIT);
 655 }
 656
 657 /* Release memory used by one plugin. */
 658
 659 static int
 660 finalize_one_plugin (void **slot, void * ARG_UNUSED (info))
 661 {
 662   struct plugin_name_args *plugin = (struct plugin_name_args *) *slot;
 663   XDELETE (plugin);
 664   return 1;
 665 }
 666
 667 /* Free memory allocated by the plugin system. */
 668
 669 void
 670 finalize_plugins (void)
 671 {
 672   if (!plugin_name_args_tab)
 673     return;
 674
 675   /* We can now delete the plugin_name_args object as it will no longer
 676      be used. Note that base_name and argv fields (both of which were also
 677      dynamically allocated) are not freed as they could still be used by
 678      the plugin code.  */
 679
 680   htab_traverse_noresize (plugin_name_args_tab, finalize_one_plugin, NULL);
 681
 682   /* PLUGIN_NAME_ARGS_TAB is no longer needed, just delete it.  */
 683   htab_delete (plugin_name_args_tab);
 684   plugin_name_args_tab = NULL;
 685 }
 686
 687 /* Used to pass options to htab_traverse callbacks. */
 688
 689 struct print_options
 690 {
 691   FILE *file;
 692   const char *indent;
 693 };
 694
 695 /* Print the version of one plugin. */
 696
 697 static int
 698 print_version_one_plugin (void **slot, void *data)
 699 {
 700   struct print_options *opt = (struct print_options *) data;
 701   struct plugin_name_args *plugin = (struct plugin_name_args *) *slot;
 702   const char *version = plugin->version ? plugin->version : "Unknown version.";
 703
 704   fprintf (opt->file, " %s%s: %s\n", opt->indent, plugin->base_name, version);
 705   return 1;
 706 }
 707
 708 /* Print the version of each plugin. */
 709
 710 void
 711 print_plugins_versions (FILE *file, const char *indent)
 712 {
 713   struct print_options opt;
 714   opt.file = file;
 715   opt.indent = indent;
 716   if (!plugin_name_args_tab || htab_elements (plugin_name_args_tab) == 0)
 717     return;
 718
 719   fprintf (file, "%sVersions of loaded plugins:\n", indent);
 720   htab_traverse_noresize (plugin_name_args_tab, print_version_one_plugin, &opt);
 721 }
 722
 723 /* Print help for one plugin. SLOT is the hash table slot. DATA is the
 724    argument to htab_traverse_noresize. */
 725
 726 static int
 727 print_help_one_plugin (void **slot, void *data)
 728 {
 729   struct print_options *opt = (struct print_options *) data;
 730   struct plugin_name_args *plugin = (struct plugin_name_args *) *slot;
 731   const char *help = plugin->help ? plugin->help : "No help available .";
 732
 733   char *dup = xstrdup (help);
 734   char *p, *nl;
 735   fprintf (opt->file, " %s%s:\n", opt->indent, plugin->base_name);
 736
 737   for (p = nl = dup; nl; p = nl)
 738     {
 739       nl = strchr (nl, '\n');
 740       if (nl)
 741         {
 742           *nl = '\0';
 743           nl++;
 744         }
 745       fprintf (opt->file, "   %s %s\n", opt->indent, p);
 746     }
 747
 748   free (dup);
 749   return 1;
 750 }
 751
 752 /* Print help for each plugin. The output goes to FILE and every line starts
 753    with INDENT. */
 754
 755 void
 756 print_plugins_help (FILE *file, const char *indent)
 757 {
 758   struct print_options opt;
 759   opt.file = file;
 760   opt.indent = indent;
 761   if (!plugin_name_args_tab || htab_elements (plugin_name_args_tab) == 0)
 762     return;
 763
 764   fprintf (file, "%sHelp for the loaded plugins:\n", indent);
 765   htab_traverse_noresize (plugin_name_args_tab, print_help_one_plugin, &opt);
 766 }
 767
 768
 769 /* Return true if plugins have been loaded.  */
 770
 771 bool
 772 plugins_active_p (void)
 773 {
 774   int event;
 775
 776   for (event = PLUGIN_PASS_MANAGER_SETUP; event < event_last; event++)
 777     if (plugin_callbacks[event])
 778       return true;
 779
 780   return false;
 781 }
 782
 783
 784 /* Dump to FILE the names and associated events for all the active
 785    plugins.  */
 786
 787 DEBUG_FUNCTION void
 788 dump_active_plugins (FILE *file)
 789 {
 790   int event;
 791
 792   if (!plugins_active_p ())
 793     return;
 794
 795   fprintf (file, FMT_FOR_PLUGIN_EVENT " | %s\n", _("Event"), _("Plugins"));
 796   for (event = PLUGIN_PASS_MANAGER_SETUP; event < event_last; event++)
 797     if (plugin_callbacks[event])
 798       {
 799         struct callback_info *ci;
 800
 801         fprintf (file, FMT_FOR_PLUGIN_EVENT " |", plugin_event_name[event]);
 802
 803         for (ci = plugin_callbacks[event]; ci; ci = ci->next)
 804           fprintf (file, " %s", ci->plugin_name);
 805
 806         putc ('\n', file);
 807       }
 808 }
 809
 810
 811 /* Dump active plugins to stderr.  */
 812
 813 DEBUG_FUNCTION void
 814 debug_active_plugins (void)
 815 {
 816   dump_active_plugins (stderr);
 817 }
 818
 819 /* Give a warning if plugins are present, before an ICE message asking
 820    to submit a bug report.  */
 821
 822 void
 823 warn_if_plugins (void)
 824 {
 825   if (plugins_active_p ())
 826     {
 827       fnotice (stderr, "*** WARNING *** there are active plugins, do not report"
 828                " this as a bug unless you can reproduce it without enabling"
 829                " any plugins.\n");
 830       dump_active_plugins (stderr);
 831     }
 832
 833 }
 834
 835 /* Likewise, as a callback from the diagnostics code.  */
 836
 837 void
 838 plugins_internal_error_function (diagnostic_context *context ATTRIBUTE_UNUSED,
 839                                  const char *msgid ATTRIBUTE_UNUSED,
 840                                  va_list *ap ATTRIBUTE_UNUSED)
 841 {
 842   warn_if_plugins ();
 843 }
 844
 845 /* The default version check. Compares every field in VERSION. */
 846
 847 bool
 848 plugin_default_version_check (struct plugin_gcc_version *gcc_version,
 849                               struct plugin_gcc_version *plugin_version)
 850 {
 851   if (!gcc_version || !plugin_version)
 852     return false;
 853
 854   if (strcmp (gcc_version->basever, plugin_version->basever))
 855     return false;
 856   if (strcmp (gcc_version->datestamp, plugin_version->datestamp))
 857     return false;
 858   if (strcmp (gcc_version->devphase, plugin_version->devphase))
 859     return false;
 860   if (strcmp (gcc_version->revision, plugin_version->revision))
 861     return false;
 862   if (strcmp (gcc_version->configuration_arguments,
 863               plugin_version->configuration_arguments))
 864     return false;
 865   return true;
 866 }
 867
 868
 869 /* Return the current value of event_last, so that plugins which provide
 870    additional functionality for events for the benefit of high-level plugins
 871    know how many valid entries plugin_event_name holds.  */
 872
 873 int
 874 get_event_last (void)
 875 {
 876   return event_last;
 877 }
 878
 879
 880 /* Retrieve the default plugin directory.  The gcc driver should have passed
 881    it as -iplugindir <dir> to the cc1 program, and it is queriable through the
 882    -print-file-name=plugin option to gcc.  */
 883 const char*
 884 default_plugin_dir_name (void)
 885 {
 886   if (!plugindir_string)
 887     fatal_error ("-iplugindir <dir> option not passed from the gcc driver");
 888   return plugindir_string;
 889 }