Index: objfiles.c
===================================================================
RCS file: /cvs/src/src/gdb/objfiles.c,v
retrieving revision 1.85
diff -u -p -u -r1.85 objfiles.c
--- objfiles.c	14 Jul 2009 14:55:06 -0000	1.85
+++ objfiles.c	17 Jul 2009 00:21:13 -0000
@@ -64,6 +64,18 @@ struct objfile *current_objfile;	/* For 
 struct objfile *symfile_objfile;	/* Main symbol table loaded from */
 struct objfile *rt_common_objfile;	/* For runtime common symbols */
 
+struct address_to_obj_section
+{
+  CORE_ADDR addr;
+  CORE_ADDR endaddr;
+  struct obj_section *section;
+};
+
+/* 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.  */
@@ -94,6 +106,7 @@ add_to_objfile_sections (struct bfd *abf
   obstack_grow (&objfile->objfile_obstack, (char *) &section, sizeof (section));
   objfile->sections_end
     = (struct obj_section *) (((size_t) objfile->sections_end) + 1);
+  objfiles_updated_p += 1;  /* Rebuild section map next time we need it.  */
 }
 
 /* Builds a section table for OBJFILE.
@@ -394,6 +407,7 @@ unlink_objfile (struct objfile *objfile)
 void
 free_objfile (struct objfile *objfile)
 {
+  objfiles_updated_p += 1;  /* Rebuild section map next time we need it.  */
   if (objfile->separate_debug_objfile)
     {
       free_objfile (objfile->separate_debug_objfile);
@@ -757,22 +771,121 @@ have_minimal_symbols (void)
   return 0;
 }
 
+/* Qsort comparison function.  */
+static int
+section_map_compare (const void *a, const void *b)
+{
+  const struct address_to_obj_section *aa =
+      (const struct address_to_obj_section *) a;
+  const struct address_to_obj_section *bb =
+      (const struct address_to_obj_section *) b;
+
+  if (aa->addr < bb->addr)
+    {
+      gdb_assert (aa->endaddr <= bb->addr);
+      return -1;
+    }
+  else if (aa->addr > bb->addr)
+    {
+      gdb_assert (aa->addr >= bb->endaddr);
+      return 1;
+    }
+  /* This can happen for separate debug-info files.  */
+  gdb_assert (aa->endaddr == bb->endaddr);
+
+  return 0;
+}
+
+/* Update PMAP, PMAP_SIZE with non-TLS sections from all objfiles.  */
+
+static void
+update_section_map (struct address_to_obj_section **pmap,
+                    int *pmap_size)
+{
+  int map_size, idx;
+  struct obj_section *s;
+  struct objfile *objfile;
+  struct address_to_obj_section *map;
+
+  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].section = s;
+        map[idx].addr = obj_section_addr (s);
+        map[idx].endaddr = obj_section_endaddr (s);
+        idx += 1;
+      }
+
+#undef insert_p
+
+  qsort (map, map_size, sizeof (*map), section_map_compare);
+
+  *pmap = map;
+  *pmap_size = map_size;
+}
+
+/* Bsearch comparison function. */
+
+int
+find_pc_section_cmp (const void *key, const void *elt)
+{
+  CORE_ADDR pc = *(CORE_ADDR *) key;
+  const struct address_to_obj_section *entry =
+      (const struct address_to_obj_section *) elt;
+
+  if (pc < entry->addr)
+    return -1;
+  if (pc < entry->endaddr)
+    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)
 {
+  static struct address_to_obj_section *sections;
+  static int num_sections;
+
   struct obj_section *s;
-  struct objfile *objfile;
+  struct address_to_obj_section *aos;
 
   /* 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;
+    }
+
+  aos = bsearch (&pc, sections, num_sections, sizeof (*sections),
+                 find_pc_section_cmp);
+  if (aos)
+    return aos->section;
 
   return NULL;
 }