2009-07-21 Paul Pluzhnikov <ppluzhnikov@google.com>

* objfiles.c (objfiles_updated_p): New variable.
	(qsort_cmp, bsearch_cmp, update_section_map): New function.
	(find_pc_section): Use bsearch.
	(set_objfiles_updated_on_exe_change): New function.
	(set_objfiles_updated_on_solib_activity): New function.
	(_initialize_objfiles): New function.

gdb/ChangeLog

@@ -1,3 +1,12 @@
+2009-07-21  Paul Pluzhnikov  <ppluzhnikov@google.com>
+	
+	* objfiles.c (objfiles_updated_p): New variable.
+	(qsort_cmp, bsearch_cmp, update_section_map): New function.
+	(find_pc_section): Use bsearch.
+	(set_objfiles_updated_on_exe_change): New function.
+	(set_objfiles_updated_on_solib_activity): New function.
+	(_initialize_objfiles): New function.
+	
 2009-06-26 Michael Eager <eager@eagercon.com>
 
 	* features/rs6000/powerpc-405.xml: New.

gdb/objfiles.c

@@ -50,6 +50,7 @@
 #include "addrmap.h"
 #include "arch-utils.h"
 #include "exec.h"
+#include "observer.h"
 
 /* Prototypes for local functions */
 
@@ -64,6 +65,11 @@ struct objfile *current_objfile;	/* For symbol file being read in */
 struct objfile *symfile_objfile;	/* Main symbol table loaded from */
 struct objfile *rt_common_objfile;	/* For runtime common symbols */
 
+/* Records whether any objfiles appeared or disappeared since we last updated
+   address to obj section map.  */
+
+static int objfiles_updated_p;
+
 /* Locate all mappable sections of a BFD file. 
    objfile_p_char is a char * to get it through
    bfd_map_over_sections; we cast it back to its proper type.  */
@@ -757,23 +763,113 @@ have_minimal_symbols (void)
   return 0;
 }
 
+/* Qsort comparison function.  */
+
+static int
+qsort_cmp (const void *a, const void *b)
+{
+  const struct obj_section *sect1 = *(const struct obj_section **) a;
+  const struct obj_section *sect2 = *(const struct obj_section **) b;
+  const CORE_ADDR sect1_addr = obj_section_addr (sect1);
+  const CORE_ADDR sect2_addr = obj_section_addr (sect2);
+
+  if (sect1_addr < sect2_addr)
+    {
+      gdb_assert (obj_section_endaddr (sect1) <= sect2_addr);
+      return -1;
+    }
+  else if (sect1_addr > sect2_addr)
+    {
+      gdb_assert (sect1_addr >= obj_section_endaddr (sect2));
+      return 1;
+    }
+  /* This can happen for separate debug-info files.  */
+  gdb_assert (obj_section_endaddr (sect1) == obj_section_endaddr (sect2));
+
+  return 0;
+}
+
+/* Update PMAP, PMAP_SIZE with non-TLS sections from all objfiles.  */
+
+static void
+update_section_map (struct obj_section ***pmap, int *pmap_size)
+{
+  int map_size, idx;
+  struct obj_section *s, **map;
+  struct objfile *objfile;
+
+  gdb_assert (objfiles_updated_p != 0);
+
+  map = *pmap;
+  xfree (map);
+
+#define insert_p(objf, sec) \
+  ((bfd_get_section_flags ((objf)->obfd, (sec)->the_bfd_section) \
+    & SEC_THREAD_LOCAL) == 0)
+
+  map_size = 0;
+  ALL_OBJSECTIONS (objfile, s)
+    if (insert_p (objfile, s))
+      map_size += 1;
+
+  map = xmalloc (map_size * sizeof (*map));
+
+  idx = 0;
+  ALL_OBJSECTIONS (objfile, s)
+    if (insert_p (objfile, s))
+      map[idx++] = s;
+
+#undef insert_p
+
+  qsort (map, map_size, sizeof (*map), qsort_cmp);
+
+  *pmap = map;
+  *pmap_size = map_size;
+}
+
+/* Bsearch comparison function. */
+
+static int
+bsearch_cmp (const void *key, const void *elt)
+{
+  const CORE_ADDR pc = *(CORE_ADDR *) key;
+  const struct obj_section *section = *(const struct obj_section **) elt;
+
+  if (pc < obj_section_addr (section))
+    return -1;
+  if (pc < obj_section_endaddr (section))
+    return 0;
+  return 1;
+}
+
 /* Returns a section whose range includes PC or NULL if none found.   */
 
 struct obj_section *
 find_pc_section (CORE_ADDR pc)
 {
-  struct obj_section *s;
-  struct objfile *objfile;
+  static struct obj_section **sections;
+  static int num_sections;
+
+  struct obj_section *s, **sp;
 
   /* Check for mapped overlay section first.  */
   s = find_pc_mapped_section (pc);
   if (s)
     return s;
 
-  ALL_OBJSECTIONS (objfile, s)
-    if (obj_section_addr (s) <= pc && pc < obj_section_endaddr (s))
-      return s;
+  if (objfiles_updated_p != 0)
+    {
+      update_section_map (&sections, &num_sections);
 
+      /* Don't need updates to section map until objfiles are added
+         or removed.  */
+      objfiles_updated_p = 0;
+    }
+
+  sp = (struct obj_section **) bsearch (&pc, sections, num_sections,
+					sizeof (*sections), bsearch_cmp);
+  if (sp != NULL)
+    return *sp;
   return NULL;
 }
 
@@ -892,3 +988,29 @@ objfile_data (struct objfile *objfile, const struct objfile_data *data)
   gdb_assert (data->index < objfile->num_data);
   return objfile->data[data->index];
 }
+
+/* Set objfiles_updated_p so section map will be rebuilt next time it
+   is used.  Called by executable_changed observer.  */
+
+static void
+set_objfiles_updated_on_exe_change (void)
+{
+  objfiles_updated_p = 1;  /* Rebuild section map next time we need it.  */
+}
+
+/* Set objfiles_updated_p so section map will be rebuilt next time it
+   is used.  Called by solib_loaded/unloaded observer.  */
+
+static void
+set_objfiles_updated_on_solib_activity (struct so_list *so_list)
+{
+  objfiles_updated_p = 1;  /* Rebuild section map next time we need it.  */
+}
+
+void
+_initialize_objfiles (void)
+{
+  observer_attach_executable_changed (set_objfiles_updated_on_exe_change);
+  observer_attach_solib_loaded (set_objfiles_updated_on_solib_activity);
+  observer_attach_solib_unloaded (set_objfiles_updated_on_solib_activity);
+}