invoke.texi (Overall Options): Document --help=.

* doc/invoke.texi (Overall Options): Document --help=.                                                        
* gcc.c (target_help_flag): Rename to print_subprocess_flag.                                                  
  (cc1_options): Pass --help= on to cc1.                                                                      
  (display_help): Add description of --help=.                                                                 
  (process_command): Add code to handle --help=.  Allow translated                                            
  --help and --target-help switches to be passed on to compiler sub-process.                                                                                               
  (main): Remove unused if statement.                                                                         
* opts.c (columns): Remove.                                                                                   
  (LEFT_COLUMN): Define.                                                                                      
  (wrap_help): Add columns argument.                                                                          
  (print_filtered_help): Change parameters to be an include bitmask,                                          
  an exclude bitmask, an any bitmask and the column width.  Move the                                          
  code to display the params list here.  Add code to display the                                              
  status of options rather than their descriptions if the quiet flag                                          
  is not active.                                                                                              
  (print_specific_help): Change parameters to be an include bitmask,                                          
  an exclude bitmask and an any bitmask.  Move code to look up the                                            
  column width here.  Decide upon the title for an options listing.                                           
  (common_handle_options): Add code to handle --help=.  Adapt code                                            
  for --help and --target-help to use the revised form of the                                                 
  print_specific_help function.                                                                               
  (print_help): Delete.                                                                                       
  (print_param_help): Delete.                                                                                 
  (print_switch): Delete.                                                                                     
* opts.h (cl_lang_count): Add prototype.                                                                      
 (CL_PARAMS, CL_WARNING, CL_OPTIMIZATION, CL_MIN_OPTION_CLASS, CL_MAX_OPTION_CLASS): New defines.            
* optc-gen.awk: Add construction of cl_lang_count.                                                            
* c.opt: Add Warning attribute to warning options and Optimization attribute to optimization options.         
* common.opt: Likewise.                                                                                       
  Add --help=.                                                                                                
  Add -fhelp and -ftarget-help as aliases for the transformed --help and --target-help options.               
* opt-functions.awk: Add code to handle Warning and Optimization attributes.

From-SVN: r121849

1 files changed, 404 insertions, 252 deletions

diff --git a/gcc/opts.c b/gcc/opts.c
index 0fa9814..daa9c9e 100644
--- a/gcc/opts.c
+++ b/gcc/opts.c
@@ -83,15 +83,12 @@ enum symbol_visibility default_visibility = VISIBILITY_DEFAULT;
 
 /* Disable unit-at-a-time for frontends that might be still broken in this
    respect.  */
-  
+
 bool no_unit_at_a_time_default;
 
 /* Global visibility options.  */
 struct visibility_flags visibility_options;
 
-/* Columns of --help display.  */
-static unsigned int columns = 80;
-
 /* What to print when a switch has no documentation.  */
 static const char undocumented_msg[] = N_("This switch lacks documentation");
 
@@ -115,12 +112,6 @@ static char *write_langs (unsigned int lang_mask);
 static void complain_wrong_lang (const char *, const struct cl_option *,
 				 unsigned int lang_mask);
 static void handle_options (unsigned int, const char **, unsigned int);
-static void wrap_help (const char *help, const char *item, unsigned int);
-static void print_target_help (void);
-static void print_help (void);
-static void print_param_help (void);
-static void print_filtered_help (unsigned int);
-static unsigned int print_switch (const char *text, unsigned int indent);
 static void set_debug_level (enum debug_info_type type, int extended,
 			     const char *arg);
 
@@ -320,7 +311,7 @@ handle_option (const char **argv, unsigned int lang_mask)
 	*(const char **) option->flag_var = arg;
 	break;
       }
-  
+
   if (option->flags & lang_mask)
     if (lang_hooks.handle_option (opt_index, arg, value) == 0)
       result = 0;
@@ -601,7 +592,7 @@ decode_options (unsigned int argc, const char **argv)
 
   if (flag_exceptions && flag_reorder_blocks_and_partition)
     {
-      inform 
+      inform
 	    ("-freorder-blocks-and-partition does not work with exceptions");
       flag_reorder_blocks_and_partition = 0;
       flag_reorder_blocks = 1;
@@ -626,13 +617,300 @@ decode_options (unsigned int argc, const char **argv)
       && (!targetm.have_named_sections
 	  || (flag_unwind_tables && targetm.unwind_tables_default)))
     {
-      inform 
+      inform
        ("-freorder-blocks-and-partition does not work on this architecture");
       flag_reorder_blocks_and_partition = 0;
       flag_reorder_blocks = 1;
     }
 }
 
+#define LEFT_COLUMN	27
+
+/* Output ITEM, of length ITEM_WIDTH, in the left column,
+   followed by word-wrapped HELP in a second column.  */
+static void
+wrap_help (const char *help,
+	   const char *item,
+	   unsigned int item_width,
+	   unsigned int columns)
+{
+  unsigned int col_width = LEFT_COLUMN;
+  unsigned int remaining, room, len;
+
+  remaining = strlen (help);
+
+  do
+    {
+      room = columns - 3 - MAX (col_width, item_width);
+      if (room > columns)
+	room = 0;
+      len = remaining;
+
+      if (room < len)
+	{
+	  unsigned int i;
+
+	  for (i = 0; help[i]; i++)
+	    {
+	      if (i >= room && len != remaining)
+		break;
+	      if (help[i] == ' ')
+		len = i;
+	      else if ((help[i] == '-' || help[i] == '/')
+		       && help[i + 1] != ' '
+		       && i > 0 && ISALPHA (help[i - 1]))
+		len = i + 1;
+	    }
+	}
+
+      printf( "  %-*.*s %.*s\n", col_width, item_width, item, len, help);
+      item_width = 0;
+      while (help[len] == ' ')
+	len++;
+      help += len;
+      remaining -= len;
+    }
+  while (remaining);
+}
+
+/* Print help for a specific front-end, etc.  */
+static void
+print_filtered_help (unsigned int include_flags,
+		     unsigned int exclude_flags,
+		     unsigned int any_flags,
+		     unsigned int columns)
+{
+  unsigned int i;
+  const char *help;
+  static char *printed = NULL;
+  bool found = false;
+  bool displayed = false;
+
+  if (include_flags == CL_PARAMS)
+    {
+      for (i = 0; i < LAST_PARAM; i++)
+	{
+	  const char *param = compiler_params[i].option;
+
+	  help = compiler_params[i].help;
+	  if (help == NULL || *help == '\0')
+	    {
+	      if (exclude_flags & CL_UNDOCUMENTED)
+		continue;
+	      help = undocumented_msg;
+	    }
+
+	  /* Get the translation.  */
+	  help = _(help);
+
+	  wrap_help (help, param, strlen (param), columns);
+	}
+      putchar ('\n');
+      return;
+    }
+
+  if (!printed)
+    printed = xcalloc (1, cl_options_count);
+
+  for (i = 0; i < cl_options_count; i++)
+    {
+      static char new_help[128];
+      const struct cl_option *option = cl_options + i;
+      unsigned int len;
+      const char *opt;
+      const char *tab;
+
+      if (include_flags == 0
+	  || ((option->flags & include_flags) != include_flags))
+	{
+	  if ((option->flags & any_flags) == 0)
+	    continue;
+	}
+
+      /* Skip unwanted switches.  */
+      if ((option->flags & exclude_flags) != 0)
+	continue;
+
+      found = true;
+      /* Skip switches that have already been printed.  */
+      if (printed[i])
+	continue;
+
+      printed[i] = true;
+
+      help = option->help;
+      if (help == NULL)
+	{
+	  if (exclude_flags & CL_UNDOCUMENTED)
+	    continue;
+	  help = undocumented_msg;
+	}
+
+      /* Get the translation.  */
+      help = _(help);
+
+      /* Find the gap between the name of the
+	 option and its descriptive text.  */
+      tab = strchr (help, '\t');
+      if (tab)
+	{
+	  len = tab - help;
+	  opt = help;
+	  help = tab + 1;
+	}
+      else
+	{
+	  opt = option->opt_text;
+	  len = strlen (opt);
+	}
+
+      /* With the -Q option enabled we change the descriptive text associated
+	 with an option to be an indication of its current setting.  */
+      if (!quiet_flag)
+	{
+	  if (len < (LEFT_COLUMN + 2))
+	    strcpy (new_help, "\t\t");
+	  else
+	    strcpy (new_help, "\t");
+
+	  if (option->flag_var != NULL)
+	    {
+	      if (option->flags & CL_JOINED)
+		{
+		  if (option->var_type == CLVC_STRING)
+		    {
+		      if (* (const char **) option->flag_var != NULL)
+			snprintf (new_help + strlen (new_help),
+				  sizeof (new_help) - strlen (new_help),
+				  * (const char **) option->flag_var);
+		    }
+		  else
+		    sprintf (new_help + strlen (new_help),
+			     "%#x", * (int *) option->flag_var);
+		}
+	      else
+		strcat (new_help, option_enabled (i)
+			? _("[enabled]") : _("[disabled]"));
+	    }
+
+	  help = new_help;
+	}
+
+      wrap_help (help, opt, len, columns);
+      displayed = true;
+    }
+
+  if (! found)
+    printf (_(" No options with the desired characteristics were found\n"));
+  else if (! displayed)
+    printf (_(" All options with the desired characteristics have already been displayed\n"));
+
+  putchar ('\n');
+}
+
+/* Display help for a specified type of option.
+   The options must have ALL of the INCLUDE_FLAGS set
+   ANY of the flags in the ANY_FLAGS set
+   and NONE of the EXCLUDE_FLAGS set.  */
+static void
+print_specific_help (unsigned int include_flags,
+		     unsigned int exclude_flags,
+		     unsigned int any_flags)
+{
+  unsigned int all_langs_mask = (1U << cl_lang_count) - 1;
+  const char * description = NULL;
+  const char * descrip_extra = "";
+  size_t i;
+  unsigned int flag;
+  static unsigned int columns = 0;
+
+  /* Sanity check: Make sure that we do not have more
+     languages than we have bits available to enumerate them.  */
+  gcc_assert ((1U << cl_lang_count) < CL_MIN_OPTION_CLASS);
+
+  /* If we have not done so already, obtain
+     the desired maximum width of the output.  */
+  if (columns == 0)
+    {
+      const char *p;
+
+      GET_ENVIRONMENT (p, "COLUMNS");
+      if (p != NULL)
+	{
+	  int value = atoi (p);
+
+	  if (value > 0)
+	    columns = value;
+	}
+
+      if (columns == 0)
+	/* Use a reasonable default.  */
+	columns = 80;
+    }
+
+  /* Decide upon the title for the options that we are going to display.  */
+  for (i = 0, flag = 1; flag <= CL_MAX_OPTION_CLASS; flag <<= 1, i ++)
+    {
+      switch (flag & include_flags)
+	{
+	case 0:
+	  break;
+
+	case CL_TARGET:
+	  description = _("The following options are target specific");
+	  break;
+	case CL_WARNING:
+	  description = _("The following options control compiler warning messages");
+	  break;
+	case CL_OPTIMIZATION:
+	  description = _("The following options control optimizations");
+	  break;
+	case CL_COMMON:
+	  description = _("The following options are language-independent");
+	  break;
+	case CL_PARAMS:
+	  description = _("The --param option recognizes the following as parameters");
+	  break;
+	default:
+	  if (i >= cl_lang_count)
+	    break;
+	  if ((exclude_flags & ((1U << cl_lang_count) - 1)) != 0)
+	    {
+	      description = _("The following options are specific to the language ");
+	      descrip_extra = lang_names [i];
+	    }
+	  else
+	    description = _("The following options are supported by, amoung others, the language ");
+	  break;
+	}
+    }
+
+  if (description == NULL)
+    {
+      if (any_flags == 0)
+	{
+	  if (include_flags == CL_UNDOCUMENTED)
+	    description = _("The following options are not documented");
+	  else
+	    {
+	      internal_error ("unrecognized include_flags 0x%x passed to print_specific_help",
+			      include_flags);
+	      return;
+	    }
+	}
+      else
+	{
+	  if (any_flags & all_langs_mask)
+	    description = _("The following options are language-related");
+	  else
+	    description = _("The following options are language-independent");
+	}
+    }
+
+  printf ("%s%s:\n", description, descrip_extra);
+  print_filtered_help (include_flags, exclude_flags, any_flags, columns);
+}
+
 /* Handle target- and language-independent options.  Return zero to
    generate an "unknown option" message.  Only options that need
    extra handling need to be listed here; if you simply want
@@ -646,20 +924,124 @@ common_handle_option (size_t scode, const char *arg, int value,
 
   switch (code)
     {
-    case OPT__help:
-      print_help ();
-      exit_after_options = true;
-      break;
-
     case OPT__param:
       handle_param (arg);
       break;
 
+    case OPT_fhelp:
+    case OPT__help:
+      {
+	unsigned int all_langs_mask = (1U << cl_lang_count) - 1;
+	unsigned int undoc_mask;
+	unsigned int i;
+
+	undoc_mask = extra_warnings ? 0 : CL_UNDOCUMENTED;
+	/* First display any single language specific options.  */
+	for (i = 0; i < cl_lang_count; i++)
+	  print_specific_help
+	    (1U << i, (all_langs_mask & (~ (1U << i))) | undoc_mask, 0);
+	/* Next display any multi language specific options.  */
+	print_specific_help (0, undoc_mask, all_langs_mask);
+	/* Then display any remaining, non-language options.  */
+	for (i = CL_MIN_OPTION_CLASS; i <= CL_MAX_OPTION_CLASS; i <<= 1)
+	  print_specific_help (i, undoc_mask, 0);
+	exit_after_options = true;
+	break;
+      }
+
+    case OPT_ftarget_help:
     case OPT__target_help:
-      print_target_help ();
+      print_specific_help (CL_TARGET, CL_UNDOCUMENTED, 0);
       exit_after_options = true;
       break;
 
+    case OPT_fhelp_:
+    case OPT__help_:
+      {
+	const char * a = arg;
+	unsigned int include_flags = 0;
+	/* Note - by default we include undocumented options when listing
+	   specific classes.  If you only want to see documented options
+	   then add ",^undocumented" to the --help= option.  e.g.:
+
+	   --help=target,^undocumented  */
+	unsigned int exclude_flags = 0;
+
+	/* Walk along the argument string, parsing each word in turn.
+	   The format is:
+	   arg = [^]{word}[,{arg}]
+	   word = {optimizers|target|warnings|undocumented|params}  */
+	while (* a != 0)
+	  {
+	    static struct
+	    {
+	      const char * string;
+	      unsigned int flag;
+	    }
+	    specifics[] =
+	    {
+	      { "optimizers", CL_OPTIMIZATION },
+	      { "target", CL_TARGET },
+	      { "warnings", CL_WARNING },
+	      { "undocumented", CL_UNDOCUMENTED },
+	      { "params", CL_PARAMS },
+	      { "joined", CL_JOINED },
+	      { "separate", CL_SEPARATE },
+	      { NULL, 0 }
+	    };
+	    unsigned int * pflags;
+	    char * comma;
+	    unsigned int len;
+	    unsigned int i;
+
+	    if (* a == '^')
+	      {
+		++ a;
+		pflags = & exclude_flags;
+	      }
+	    else
+	      pflags = & include_flags;
+
+	    comma = strchr (a, ',');
+	    if (comma == NULL)
+	      len = strlen (a);
+	    else
+	      len = comma - a;
+
+	    for (i = 0; specifics[i].string != NULL; i++)
+	      if (strncasecmp (a, specifics[i].string, len) == 0)
+		{
+		  * pflags |= specifics[i].flag;
+		  break;
+		}
+
+	    if (specifics[i].string == NULL)
+	      {
+		/* Check to see if the string matches a language name.  */
+		for (i = 0; i < cl_lang_count; i++)
+		  if (strncasecmp (a, lang_names[i], len) == 0)
+		    {
+		      * pflags |= 1U << i;
+		      break;
+		    }
+
+		if (i == cl_lang_count)
+		  fnotice (stderr,
+			   "warning: unrecognized argument to --help= switch: %.*s\n",
+			   len, a);
+	      }
+
+	    if (comma == NULL)
+	      break;
+	    a = comma + 1;
+	  }
+
+	if (include_flags)
+	  print_specific_help (include_flags, exclude_flags, 0);
+	exit_after_options = true;
+	break;
+      }
+
     case OPT__version:
       print_version (stderr, "");
       exit_after_options = true;
@@ -684,6 +1066,7 @@ common_handle_option (size_t scode, const char *arg, int value,
       {
 	char *new_option;
 	int option_index;
+
 	new_option = XNEWVEC (char, strlen (arg) + 2);
 	new_option[0] = 'W';
 	strcpy (new_option+1, arg);
@@ -819,7 +1202,7 @@ common_handle_option (size_t scode, const char *arg, int value,
 
     case OPT_fpack_struct_:
       if (value <= 0 || (value & (value - 1)) || value > 16)
-	error("structure alignment must be a small power of two, not %d", value);
+	error ("structure alignment must be a small power of two, not %d", value);
       else
 	{
 	  initial_max_fld_align = value;
@@ -1153,238 +1536,6 @@ set_debug_level (enum debug_info_type type, int extended, const char *arg)
     }
 }
 
-/* Display help for target options.  */
-static void
-print_target_help (void)
-{
-  unsigned int i;
-  static bool displayed = false;
-
-  /* Avoid double printing for --help --target-help.  */
-  if (displayed)
-    return;
-
-  displayed = true;
-  for (i = 0; i < cl_options_count; i++)
-    if ((cl_options[i].flags & (CL_TARGET | CL_UNDOCUMENTED)) == CL_TARGET)
-      {
-	printf (_("\nTarget specific options:\n"));
-	print_filtered_help (CL_TARGET);
-	break;
-      }
-}
-
-/* Output --help text.  */
-static void
-print_help (void)
-{
-  size_t i;
-  const char *p;
-
-  GET_ENVIRONMENT (p, "COLUMNS");
-  if (p)
-    {
-      int value = atoi (p);
-      if (value > 0)
-	columns = value;
-    }
-
-  puts (_("The following options are language-independent:\n"));
-
-  print_filtered_help (CL_COMMON);
-  print_param_help ();
-
-  for (i = 0; lang_names[i]; i++)
-    {
-      printf (_("The %s front end recognizes the following options:\n\n"),
-	      lang_names[i]);
-      print_filtered_help (1U << i);
-    }
-  print_target_help ();
-}
-
-/* Print the help for --param.  */
-static void
-print_param_help (void)
-{
-  size_t i;
-
-  puts (_("The --param option recognizes the following as parameters:\n"));
-
-  for (i = 0; i < LAST_PARAM; i++)
-    {
-      const char *help = compiler_params[i].help;
-      const char *param = compiler_params[i].option;
-
-      if (help == NULL || *help == '\0')
-	help = undocumented_msg;
-
-      /* Get the translation.  */
-      help = _(help);
-
-      wrap_help (help, param, strlen (param));
-    }
-
-  putchar ('\n');
-}
-
-/* Print help for a specific front-end, etc.  */
-static void
-print_filtered_help (unsigned int flag)
-{
-  unsigned int i, len, filter, indent = 0;
-  bool duplicates = false;
-  const char *help, *opt, *tab;
-  static char *printed;
-
-  if (flag == CL_COMMON || flag == CL_TARGET)
-    {
-      filter = flag;
-      if (!printed)
-	printed = xmalloc (cl_options_count);
-      memset (printed, 0, cl_options_count);
-    }
-  else
-    {
-      /* Don't print COMMON options twice.  */
-      filter = flag | CL_COMMON;
-
-      for (i = 0; i < cl_options_count; i++)
-	{
-	  if ((cl_options[i].flags & filter) != flag)
-	    continue;
-
-	  /* Skip help for internal switches.  */
-	  if (cl_options[i].flags & CL_UNDOCUMENTED)
-	    continue;
-
-	  /* Skip switches that have already been printed, mark them to be
-	     listed later.  */
-	  if (printed[i])
-	    {
-	      duplicates = true;
-	      indent = print_switch (cl_options[i].opt_text, indent);
-	    }
-	}
-
-      if (duplicates)
-	{
-	  putchar ('\n');
-	  putchar ('\n');
-	}
-    }
-
-  for (i = 0; i < cl_options_count; i++)
-    {
-      if ((cl_options[i].flags & filter) != flag)
-	continue;
-
-      /* Skip help for internal switches.  */
-      if (cl_options[i].flags & CL_UNDOCUMENTED)
-	continue;
-
-      /* Skip switches that have already been printed.  */
-      if (printed[i])
-	continue;
-
-      printed[i] = true;
-
-      help = cl_options[i].help;
-      if (!help)
-	help = undocumented_msg;
-
-      /* Get the translation.  */
-      help = _(help);
-
-      tab = strchr (help, '\t');
-      if (tab)
-	{
-	  len = tab - help;
-	  opt = help;
-	  help = tab + 1;
-	}
-      else
-	{
-	  opt = cl_options[i].opt_text;
-	  len = strlen (opt);
-	}
-
-      wrap_help (help, opt, len);
-    }
-
-  putchar ('\n');
-}
-
-/* Output ITEM, of length ITEM_WIDTH, in the left column, followed by
-   word-wrapped HELP in a second column.  */
-static unsigned int
-print_switch (const char *text, unsigned int indent)
-{
-  unsigned int len = strlen (text) + 1; /* trailing comma */
-
-  if (indent)
-    {
-      putchar (',');
-      if (indent + len > columns)
-	{
-	  putchar ('\n');
-	  putchar (' ');
-	  indent = 1;
-	}
-    }
-  else
-    putchar (' ');
-
-  putchar (' ');
-  fputs (text, stdout);
-
-  return indent + len + 1;
-}
-
-/* Output ITEM, of length ITEM_WIDTH, in the left column, followed by
-   word-wrapped HELP in a second column.  */
-static void
-wrap_help (const char *help, const char *item, unsigned int item_width)
-{
-  unsigned int col_width = 27;
-  unsigned int remaining, room, len;
-
-  remaining = strlen (help);
-
-  do
-    {
-      room = columns - 3 - MAX (col_width, item_width);
-      if (room > columns)
-	room = 0;
-      len = remaining;
-
-      if (room < len)
-	{
-	  unsigned int i;
-
-	  for (i = 0; help[i]; i++)
-	    {
-	      if (i >= room && len != remaining)
-		break;
-	      if (help[i] == ' ')
-		len = i;
-	      else if ((help[i] == '-' || help[i] == '/')
-		       && help[i + 1] != ' '
-		       && i > 0 && ISALPHA (help[i - 1]))
-		len = i + 1;
-	    }
-	}
-
-      printf( "  %-*.*s %.*s\n", col_width, item_width, item, len, help);
-      item_width = 0;
-      while (help[len] == ' ')
-	len++;
-      help += len;
-      remaining -= len;
-    }
-  while (remaining);
-}
-
 /* Return 1 if OPTION is enabled, 0 if it is disabled, or -1 if it isn't
    a simple on-off switch.  */
 
@@ -1392,6 +1543,7 @@ int
 option_enabled (int opt_idx)
 {
   const struct cl_option *option = &(cl_options[opt_idx]);
+
   if (option->flag_var)
     switch (option->var_type)
       {