Let expand_symtabs_matching short-circuit

This changes expand_symtabs_exp_notify_ftype to return bool, and
updates all the uses.  Now, if the notification function returns
false, the call is short-circuited and stops examining symtabs.  This
is a step toward replacing map_symtabs_matching_filename with
expand_symtabs_matching.

gdb/ChangeLog
2021-04-17  Tom Tromey  <tom@tromey.com>

	* symtab.c (default_collect_symbol_completion_matches_break_on):
	Update.
	* symfile.h (expand_symtabs_matching): Return bool.
	* symfile.c (expand_symtabs_matching): Return bool.
	* symfile-debug.c (objfile::expand_symtabs_matching): Return
	bool.
	* quick-symbol.h (expand_symtabs_exp_notify_ftype): Return bool.
	(struct quick_symbol_functions) <expand_symtabs_matching>: Return
	bool.
	* psymtab.c (psymbol_functions::expand_symtabs_matching): Return
	bool.
	* psympriv.h (struct psymbol_functions)
	<expand_symtabs_matching>: Return bool.
	* objfiles.h (struct objfile) <expand_symtabs_matching>: Return
	bool.
	* dwarf2/read.c (struct dwarf2_gdb_index)
	<expand_symtabs_matching>: Return bool.
	(struct dwarf2_debug_names_index) <expand_symtabs_matching>:
	Return bool.
	(dw2_expand_symtabs_matching_symbol): Return bool.
	(dw2_expand_symtabs_matching_one, dw2_expand_marked_cus)
	(dw2_expand_symtabs_matching)
	(dwarf2_gdb_index::expand_symtabs_matching)
	(dwarf2_debug_names_index::expand_symtabs_matching)
	(dwarf2_debug_names_index::expand_symtabs_matching): Return bool.

gdb/ChangeLog

@@ -1,3 +1,31 @@
+2021-04-17  Tom Tromey  <tom@tromey.com>
+
+	* symtab.c (default_collect_symbol_completion_matches_break_on):
+	Update.
+	* symfile.h (expand_symtabs_matching): Return bool.
+	* symfile.c (expand_symtabs_matching): Return bool.
+	* symfile-debug.c (objfile::expand_symtabs_matching): Return
+	bool.
+	* quick-symbol.h (expand_symtabs_exp_notify_ftype): Return bool.
+	(struct quick_symbol_functions) <expand_symtabs_matching>: Return
+	bool.
+	* psymtab.c (psymbol_functions::expand_symtabs_matching): Return
+	bool.
+	* psympriv.h (struct psymbol_functions)
+	<expand_symtabs_matching>: Return bool.
+	* objfiles.h (struct objfile) <expand_symtabs_matching>: Return
+	bool.
+	* dwarf2/read.c (struct dwarf2_gdb_index)
+	<expand_symtabs_matching>: Return bool.
+	(struct dwarf2_debug_names_index) <expand_symtabs_matching>:
+	Return bool.
+	(dw2_expand_symtabs_matching_symbol): Return bool.
+	(dw2_expand_symtabs_matching_one, dw2_expand_marked_cus)
+	(dw2_expand_symtabs_matching)
+	(dwarf2_gdb_index::expand_symtabs_matching)
+	(dwarf2_debug_names_index::expand_symtabs_matching)
+	(dwarf2_debug_names_index::expand_symtabs_matching): Return bool.
+
 2021-04-17  Tom Tromey  <tom@tromey.com>
 
 	* quick-symbol.h (enum block_search_flag_values): New.

gdb/dwarf2/read.c

@@ -2283,7 +2283,7 @@ struct dwarf2_gdb_index : public dwarf2_base_index_functions
      gdb::function_view<symbol_found_callback_ftype> callback,
      symbol_compare_ftype *ordered_compare) override;
 
-  void expand_symtabs_matching
+  bool expand_symtabs_matching
     (struct objfile *objfile,
      gdb::function_view<expand_symtabs_file_matcher_ftype> file_matcher,
      const lookup_name_info *lookup_name,
@@ -2312,7 +2312,7 @@ struct dwarf2_debug_names_index : public dwarf2_base_index_functions
      gdb::function_view<symbol_found_callback_ftype> callback,
      symbol_compare_ftype *ordered_compare) override;
 
-  void expand_symtabs_matching
+  bool expand_symtabs_matching
     (struct objfile *objfile,
      gdb::function_view<expand_symtabs_file_matcher_ftype> file_matcher,
      const lookup_name_info *lookup_name,
@@ -3822,7 +3822,7 @@ dwarf2_base_index_functions::expand_symtabs_with_fullname
     }
 }
 
-static void
+static bool
 dw2_expand_symtabs_matching_symbol
   (mapped_index_base &index,
    const lookup_name_info &lookup_name_in,
@@ -3830,7 +3830,7 @@ dw2_expand_symtabs_matching_symbol
    gdb::function_view<bool (offset_type)> match_callback,
    dwarf2_per_objfile *per_objfile);
 
-static void
+static bool
 dw2_expand_symtabs_matching_one
   (dwarf2_per_cu_data *per_cu,
    dwarf2_per_objfile *per_objfile,
@@ -4125,7 +4125,7 @@ mapped_index_base::build_name_components (dwarf2_per_objfile *per_objfile)
    symbol name that matches, calls MATCH_CALLBACK, passing it the
    symbol's index in the mapped_index_base symbol table.  */
 
-static void
+static bool
 dw2_expand_symtabs_matching_symbol
   (mapped_index_base &index,
    const lookup_name_info &lookup_name_in,
@@ -4210,12 +4210,16 @@ dw2_expand_symtabs_matching_symbol
 
   /* Finally call the callback, once per match.  */
   ULONGEST prev = -1;
+  bool result = true;
   for (offset_type idx : matches)
     {
       if (prev != idx)
 	{
 	  if (!match_callback (idx))
+	    {
+	      result = false;
 	      break;
+	    }
 	  prev = idx;
 	}
     }
@@ -4223,6 +4227,8 @@ dw2_expand_symtabs_matching_symbol
   /* Above we use a type wider than idx's for 'prev', since 0 and
      (offset_type)-1 are both possible values.  */
   static_assert (sizeof (prev) > sizeof (offset_type), "");
+
+  return result;
 }
 
 #if GDB_SELF_TEST
@@ -4663,7 +4669,7 @@ run_test ()
    dw_expand_symtabs_matching_file_matcher), expand the CU and call
    EXPANSION_NOTIFY on it.  */
 
-static void
+static bool
 dw2_expand_symtabs_matching_one
   (dwarf2_per_cu_data *per_cu,
    dwarf2_per_objfile *per_objfile,
@@ -4679,15 +4685,16 @@ dw2_expand_symtabs_matching_one
       gdb_assert (symtab != nullptr);
 
       if (expansion_notify != NULL && symtab_was_null)
-	expansion_notify (symtab);
+	return expansion_notify (symtab);
     }
+  return true;
 }
 
 /* Helper for dw2_expand_matching symtabs.  Called on each symbol
    matched, to expand corresponding CUs that were marked.  IDX is the
    index of the symbol name that matched.  */
 
-static void
+static bool
 dw2_expand_marked_cus
   (dwarf2_per_objfile *per_objfile, offset_type idx,
    gdb::function_view<expand_symtabs_file_matcher_ftype> file_matcher,
@@ -4764,9 +4771,12 @@ dw2_expand_marked_cus
 	}
 
       dwarf2_per_cu_data *per_cu = per_objfile->per_bfd->get_cutu (cu_index);
-      dw2_expand_symtabs_matching_one (per_cu, per_objfile, file_matcher,
+      if (!dw2_expand_symtabs_matching_one (per_cu, per_objfile, file_matcher,
-				       expansion_notify);
+					    expansion_notify))
+	return false;
     }
+
+  return true;
 }
 
 /* If FILE_MATCHER is non-NULL, set all the
@@ -4846,7 +4856,7 @@ dw_expand_symtabs_matching_file_matcher
     }
 }
 
-void
+bool
 dwarf2_gdb_index::expand_symtabs_matching
     (struct objfile *objfile,
      gdb::function_view<expand_symtabs_file_matcher_ftype> file_matcher,
@@ -4859,7 +4869,7 @@ dwarf2_gdb_index::expand_symtabs_matching
 
   /* index_table is NULL if OBJF_READNOW.  */
   if (!per_objfile->per_bfd->index_table)
-    return;
+    return true;
 
   dw_expand_symtabs_matching_file_matcher (per_objfile, file_matcher);
 
@@ -4869,22 +4879,28 @@ dwarf2_gdb_index::expand_symtabs_matching
 	{
 	  QUIT;
 
-	  dw2_expand_symtabs_matching_one (per_cu, per_objfile,
+	  if (!dw2_expand_symtabs_matching_one (per_cu, per_objfile,
-					   file_matcher, expansion_notify);
+						file_matcher,
+						expansion_notify))
+	    return false;
 	}
-      return;
+      return true;
     }
 
   mapped_index &index = *per_objfile->per_bfd->index_table;
 
-  dw2_expand_symtabs_matching_symbol (index, *lookup_name,
+  bool result
+    = dw2_expand_symtabs_matching_symbol (index, *lookup_name,
 					  symbol_matcher,
 					  [&] (offset_type idx)
     {
-      dw2_expand_marked_cus (per_objfile, idx, file_matcher, expansion_notify,
+      if (!dw2_expand_marked_cus (per_objfile, idx, file_matcher,
-			     kind);
+				  expansion_notify, kind))
+	return false;
       return true;
     }, per_objfile);
+
+  return result;
 }
 
 /* A helper for dw2_find_pc_sect_compunit_symtab which finds the most specific
@@ -5896,7 +5912,7 @@ dwarf2_debug_names_index::map_matching_symbols
     }
 }
 
-void
+bool
 dwarf2_debug_names_index::expand_symtabs_matching
   (struct objfile *objfile,
    gdb::function_view<expand_symtabs_file_matcher_ftype> file_matcher,
@@ -5909,7 +5925,7 @@ dwarf2_debug_names_index::expand_symtabs_matching
 
   /* debug_names_table is NULL if OBJF_READNOW.  */
   if (!per_objfile->per_bfd->debug_names_table)
-    return;
+    return true;
 
   dw_expand_symtabs_matching_file_matcher (per_objfile, file_matcher);
 
@@ -5919,15 +5935,18 @@ dwarf2_debug_names_index::expand_symtabs_matching
 	{
 	  QUIT;
 
-	  dw2_expand_symtabs_matching_one (per_cu, per_objfile, file_matcher,
+	  if (!dw2_expand_symtabs_matching_one (per_cu, per_objfile,
-					   expansion_notify);
+						file_matcher,
+						expansion_notify))
+	    return false;
 	}
-      return;
+      return true;
     }
 
   mapped_debug_names &map = *per_objfile->per_bfd->debug_names_table;
 
-  dw2_expand_symtabs_matching_symbol (map, *lookup_name,
+  bool result
+    = dw2_expand_symtabs_matching_symbol (map, *lookup_name,
 					  symbol_matcher,
 					  [&] (offset_type namei)
     {
@@ -5937,10 +5956,14 @@ dwarf2_debug_names_index::expand_symtabs_matching
 
       struct dwarf2_per_cu_data *per_cu;
       while ((per_cu = iter.next ()) != NULL)
-	dw2_expand_symtabs_matching_one (per_cu, per_objfile, file_matcher,
+	if (!dw2_expand_symtabs_matching_one (per_cu, per_objfile,
-					 expansion_notify);
+					      file_matcher,
+					      expansion_notify))
+	  return false;
       return true;
     }, per_objfile);
+
+  return result;
 }
 
 /* Get the content of the .gdb_index section of OBJ.  SECTION_OWNER should point

gdb/objfiles.h

@@ -603,7 +603,7 @@ public:
      symbol_compare_ftype *ordered_compare);
 
   /* See quick_symbol_functions.  */
-  void expand_symtabs_matching
+  bool expand_symtabs_matching
     (gdb::function_view<expand_symtabs_file_matcher_ftype> file_matcher,
      const lookup_name_info *lookup_name,
      gdb::function_view<expand_symtabs_symbol_matcher_ftype> symbol_matcher,

gdb/psympriv.h

@@ -541,7 +541,7 @@ struct psymbol_functions : public quick_symbol_functions
      gdb::function_view<symbol_found_callback_ftype> callback,
      symbol_compare_ftype *ordered_compare) override;
 
-  void expand_symtabs_matching
+  bool expand_symtabs_matching
     (struct objfile *objfile,
      gdb::function_view<expand_symtabs_file_matcher_ftype> file_matcher,
      const lookup_name_info *lookup_name,

gdb/psymtab.c

@@ -1293,7 +1293,7 @@ recursively_search_psymtabs
 /* Psymtab version of expand_symtabs_matching.  See its definition in
    the definition of quick_symbol_functions in symfile.h.  */
 
-void
+bool
 psymbol_functions::expand_symtabs_matching
   (struct objfile *objfile,
    gdb::function_view<expand_symtabs_file_matcher_ftype> file_matcher,
@@ -1346,9 +1346,12 @@ psymbol_functions::expand_symtabs_matching
 	    psymtab_to_symtab (objfile, ps);
 
 	  if (expansion_notify != NULL)
-	    expansion_notify (symtab);
+	    if (!expansion_notify (symtab))
+	      return false;
 	}
     }
+
+  return true;
 }
 
 /* Psymtab version of has_symbols.  See its definition in

gdb/quick-symbol.h

@@ -52,9 +52,11 @@ typedef bool (expand_symtabs_file_matcher_ftype) (const char *filename,
 typedef bool (expand_symtabs_symbol_matcher_ftype) (const char *name);
 
 /* Callback for quick_symbol_functions->expand_symtabs_matching
-   to be called after a symtab has been expanded.  */
+   to be called after a symtab has been expanded.  If this returns
+   true, more symtabs are checked; if it returns false, iteration
+   stops.  */
 
-typedef void (expand_symtabs_exp_notify_ftype) (compunit_symtab *symtab);
+typedef bool (expand_symtabs_exp_notify_ftype) (compunit_symtab *symtab);
 
 /* The "quick" symbol functions exist so that symbol readers can
    avoiding an initial read of all the symbols.  For example, symbol
@@ -206,8 +208,12 @@ struct quick_symbol_functions
 
      If SYMBOL_MATCHER returns false, then the symbol is skipped.
 
-     Otherwise, the symbol's symbol table is expanded.  */
+     Otherwise, the symbol's symbol table is expanded and the
-  virtual void expand_symtabs_matching
+     notification function is called.  If the notification function
+     returns false, execution stops and this method returns false.
+     Otherwise, more files are considered.  This method will return
+     true if all calls to the notification function return true.  */
+  virtual bool expand_symtabs_matching
     (struct objfile *objfile,
      gdb::function_view<expand_symtabs_file_matcher_ftype> file_matcher,
      const lookup_name_info *lookup_name,

gdb/symfile-debug.c

@@ -265,7 +265,7 @@ objfile::map_matching_symbols
 				callback, ordered_compare);
 }
 
-void
+bool
 objfile::expand_symtabs_matching
   (gdb::function_view<expand_symtabs_file_matcher_ftype> file_matcher,
    const lookup_name_info *lookup_name,
@@ -283,8 +283,11 @@ objfile::expand_symtabs_matching
 		      search_domain_name (kind));
 
   for (const auto &iter : qf)
-    iter->expand_symtabs_matching (this, file_matcher, lookup_name,
+    if (!iter->expand_symtabs_matching (this, file_matcher, lookup_name,
-				   symbol_matcher, expansion_notify, kind);
+					symbol_matcher, expansion_notify,
+					kind))
+      return false;
+  return true;
 }
 
 struct compunit_symtab *

gdb/symfile.c

@@ -3716,7 +3716,7 @@ symfile_free_objfile (struct objfile *objfile)
    Expand all symtabs that match the specified criteria.
    See quick_symbol_functions.expand_symtabs_matching for details.  */
 
-void
+bool
 expand_symtabs_matching
   (gdb::function_view<expand_symtabs_file_matcher_ftype> file_matcher,
    const lookup_name_info &lookup_name,
@@ -3725,10 +3725,12 @@ expand_symtabs_matching
    enum search_domain kind)
 {
   for (objfile *objfile : current_program_space->objfiles ())
-    objfile->expand_symtabs_matching (file_matcher,
+    if (!objfile->expand_symtabs_matching (file_matcher,
 					   &lookup_name,
 					   symbol_matcher,
-				      expansion_notify, kind);
+					   expansion_notify, kind))
+      return false;
+  return true;
 }
 
 /* Wrapper around the quick_symbol_functions map_symbol_filenames "method".

gdb/symfile.h

@@ -321,7 +321,7 @@ symfile_segment_data_up get_symfile_segment_data (bfd *abfd);
 
 extern scoped_restore_tmpl<int> increment_reading_symtab (void);
 
-void expand_symtabs_matching
+bool expand_symtabs_matching
   (gdb::function_view<expand_symtabs_file_matcher_ftype> file_matcher,
    const lookup_name_info &lookup_name,
    gdb::function_view<expand_symtabs_symbol_matcher_ftype> symbol_matcher,

gdb/symtab.c

@@ -5730,6 +5730,7 @@ default_collect_symbol_completion_matches_break_on
 			       add_symtab_completions (symtab,
 						       tracker, mode, lookup_name,
 						       sym_text, word, code);
+			       return true;
 			     },
 			   ALL_DOMAIN);