Inside the processed template:
  x1 = x1_defined_in_template
  x2 = x2_defined_in_stash_set
  x3 = x3_defined_in_process_t_vars
$VAR1 = {
          'component' => '',
          'x1' => 'x1_defined_in_template',
          'x2' => 'x2_defined_in_stash_set',
          'x3' => 'x3_defined_in_process_t_vars'
        };