[patch] Code cleanup: Remove commands_left [Do not bpstat_clear_actions on throw_exception]

[Jan Kratochvil <jan dot kratochvil at redhat dot com>]

On Thu, 18 Aug 2011 18:42:19 +0200, Pedro Alves wrote:
> Since bs->commands is refcounted, I don't understand
> why we need bs->commands_left at all.  bpstat_do_actions_1
> could instead itself skip the first command if it is "silent".

To make the discussion easier let's remove it first.

The patch is simple, I will check it in soon myself.
No regressions on {x86_64,x86_64-m32,i686}-fedora16pre-linux-gnu.


Thanks,
Jan


gdb/
2011-08-18  Jan Kratochvil  <jan.kratochvil@redhat.com>

	Code cleanup.
	* breakpoint.c (bpstat_clear_actions): Remove clearing of commands_left.
	(command_line_is_silent): New function.
	(bpstat_do_actions_1): No longer use commands_left, use
	command_line_is_silent for commands.
	(bpstat_alloc): Remove clearing of commands_left.
	(bpstat_stop_status): Remove initialization of commands_left, use
	command_line_is_silent.
	* breakpoint.h (struct bpstats): Remove commands_left.

--- a/gdb/breakpoint.c
+++ b/gdb/breakpoint.c
@@ -3194,7 +3194,7 @@ bpstat_clear_actions (bpstat bs)
   for (; bs != NULL; bs = bs->next)
     {
       decref_counted_command_line (&bs->commands);
-      bs->commands_left = NULL;
+
       if (bs->old_val != NULL)
 	{
 	  value_free (bs->old_val);
@@ -3231,6 +3231,16 @@ cleanup_executing_breakpoints (void *ignore)
   executing_breakpoint_commands = 0;
 }
 
+/* Return non-zero iff CMD as the first line of a command sequence is `silent'
+   or its equivalent.  */
+
+static int
+command_line_is_silent (struct command_line *cmd)
+{
+  return cmd && (strcmp ("silent", cmd->line) == 0
+		 || (xdb_commands && strcmp ("Q", cmd->line) == 0));
+}
+
 /* Execute all the commands associated with all the breakpoints at
    this location.  Any of these commands could cause the process to
    proceed beyond this point, etc.  We look out for such changes by
@@ -3279,10 +3289,13 @@ bpstat_do_actions_1 (bpstat *bsp)
          the tree when we're done.  */
       ccmd = bs->commands;
       bs->commands = NULL;
-      this_cmd_tree_chain
-	= make_cleanup_decref_counted_command_line (&ccmd);
-      cmd = bs->commands_left;
-      bs->commands_left = NULL;
+      this_cmd_tree_chain = make_cleanup_decref_counted_command_line (&ccmd);
+      cmd = ccmd ? ccmd->commands : NULL;
+      if (command_line_is_silent (cmd))
+	{
+	  /* The action has been already done by bpstat_stop_status.  */
+	  cmd = cmd->next;
+	}
 
       while (cmd != NULL)
 	{
@@ -3474,7 +3487,6 @@ bpstat_alloc (struct bp_location *bl, bpstat **bs_link_pointer)
   incref_bp_location (bl);
   /* If the condition is false, etc., don't do the commands.  */
   bs->commands = NULL;
-  bs->commands_left = NULL;
   bs->old_val = NULL;
   bs->print_it = print_it_normal;
   return bs;
@@ -4151,16 +4163,9 @@ bpstat_stop_status (struct address_space *aspace,
 		bs->print = 0;
 	      bs->commands = b->commands;
 	      incref_counted_command_line (bs->commands);
-	      bs->commands_left = bs->commands ? bs->commands->commands : NULL;
-	      if (bs->commands_left
-		  && (strcmp ("silent", bs->commands_left->line) == 0
-		      || (xdb_commands
-			  && strcmp ("Q",
-				     bs->commands_left->line) == 0)))
-		{
-		  bs->commands_left = bs->commands_left->next;
-		  bs->print = 0;
-		}
+	      if (command_line_is_silent (bs->commands
+					  ? bs->commands->commands : NULL))
+		bs->print = 0;
 	    }
 
 	  /* Print nothing for this entry if we don't stop or don't print.  */
--- a/gdb/breakpoint.h
+++ b/gdb/breakpoint.h
@@ -950,10 +950,6 @@ struct bpstats
     /* The associated command list.  */
     struct counted_command_line *commands;
 
-    /* Commands left to be done.  This points somewhere in
-       base_command.  */
-    struct command_line *commands_left;
-
     /* Old value associated with a watchpoint.  */
     struct value *old_val;