Function bind_routine_parameter_references 

pub fn bind_routine_parameter_references(
    routines: &dyn RoutineResolution,
    plan: &mut UnifiedPlan,
    params: &[SQLParam],
    ctes: &BindingContext<'_>,
    parameters: &RoutineParameterScope,
) -> Result<(), SQLError>

Resolve the names in one statement of a SQL routine’s body that refer to the routine’s parameters, against the catalog that ctes describes, as PostgreSQL’s parser resolves them with the hooks sql_fn_parser_setup installs. The routine calls the statement makes are left to its analysis.