Generate an index to an ungeneratable list of struct

Hi,

How do i generate an index to a list of struct with constraints.

For example i have the following struct and list:

struct se_cte_free_mem_area_s
{
!address_start : u64_t;
!address_end : u64_t;

area_size : u64_t;

...

};

!free_mem_areas : list of se_cte_free_mem_area_s;

and i want to generate on the fly an index to the list with constraint (For example where  address_start <= address_x <= address_end)?

Thanks,

Yanir.