Usage of deprecated functions in functions.php

I’ve recently noticed a slowness in the admin dashboard while posting new articles. This along with discussions on the plugin forum (tx to joostdevalk) lead to defining debug to true in the wp-config.php file. This is what I found:

– get_settings is deprecated since 2.1. Use get_option() in /public_html/wp-includes/functions.php on line 3237
– register_widget_control is deprecated since 2.8. Use wp_register_widget_control() in /public_html/wp-includes/functions.php on line 3237
– register_sidebar_widget is deprecated since 2.8. Use wp_register_widget_control() in /public_html/wp-includes/functions.php on line 3237

My question is: are these coming from the theme files or are these an issue in WP files themselves?

Thanks to anyone who might have a clue.