wp-includes/class-wp-xmlrpc-server.php:247Serves the XML-RPC request.
public function serve_request() { $this->IXR_Server( $this->methods ); }Introduced in 2.9.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/class-wp-xmlrpc-server.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.