gdb/

* gdbint.texinfo (Target Vector Definition): Move most
	content into Existing Targets.  Add a menu.
	(Existing Targets): New section, moved from Target Vector
	Definition.  Use @subsection.
	(Managing Execution State): New section.
gdb/doc/
	* remote-sim.c (gdbsim_kill): Call target_mourn_inferior.
	(gdbsim_load): Don't bother to adjust inferior_ptid here.
	(gdbsim_create_inferior): Mark the simulator as running.
	(gdbsim_open): Don't bother fetching registers.  Mark
	the target as not running.
	(gdbsim_xfer): When the program is not running, pass memory
	requests down.
	(gdbsim_mourn_inferior): Mark the target as not running.
	* target.c (target_mark_running, target_mark_exited): New.
	* target.h (target_has_execution): Update the comment.
	(target_mark_running, target_mark_exited): New prototypes.

gdb/remote-sim.c

@@ -383,8 +383,8 @@ gdbsim_kill (void)
     printf_filtered ("gdbsim_kill\n");
 
   /* There is no need to `kill' running simulator - the simulator is
-     not running */
-  inferior_ptid = null_ptid;
+     not running.  Mourning it is enough.  */
+  target_mourn_inferior ();
 }
 
 /* Load an executable file into the target process.  This is expected to
@@ -410,8 +410,6 @@ gdbsim_load (char *args, int fromtty)
   if (sr_get_debug ())
     printf_filtered ("gdbsim_load: prog \"%s\"\n", prog);
 
-  inferior_ptid = null_ptid;
-
   /* FIXME: We will print two messages on error.
      Need error to either not print anything if passed NULL or need
      another routine that doesn't take any arguments.  */
@@ -469,6 +467,7 @@ gdbsim_create_inferior (char *exec_file, char *args, char **env, int from_tty)
   sim_create_inferior (gdbsim_desc, exec_bfd, argv, env);
 
   inferior_ptid = pid_to_ptid (42);
+  target_mark_running (&gdbsim_ops);
   insert_breakpoints ();	/* Needed to get correct instruction in cache */
 
   clear_proceed_status ();
@@ -543,8 +542,12 @@ gdbsim_open (char *args, int from_tty)
     error (_("unable to create simulator instance"));
 
   push_target (&gdbsim_ops);
-  target_fetch_registers (-1);
   printf_filtered ("Connected to the simulator.\n");
+
+  /* There's nothing running after "target sim" or "load"; not until
+     "run".  */
+  inferior_ptid = null_ptid;
+  target_mark_exited (&gdbsim_ops);
 }
 
 /* Does whatever cleanup is required for a target that we are no longer
@@ -747,6 +750,12 @@ gdbsim_xfer_inferior_memory (CORE_ADDR memaddr, gdb_byte *myaddr, int len,
 			     int write, struct mem_attrib *attrib,
 			     struct target_ops *target)
 {
+  /* If no program is running yet, then ignore the simulator for
+     memory.  Pass the request down to the next target, hopefully
+     an exec file.  */
+  if (!target_has_execution)
+    return 0;
+
   if (!program_loaded)
     error (_("No program loaded."));
 
@@ -802,6 +811,7 @@ gdbsim_mourn_inferior (void)
     printf_filtered ("gdbsim_mourn_inferior:\n");
 
   remove_breakpoints ();
+  target_mark_exited (&gdbsim_ops);
   generic_mourn_inferior ();
 }