There is no statutory obligation on marriage leave; hence, it differs from company to company. In general, most companies may not have such a policy, and employees who are getting married may avail leave from their accumulated balances.
Considering the high competition in the market, most managements don't prefer any additional leave, i.e., other than statutory, and they opt for a lump sum amount or article worth of xxxxxx amount. They will fix the amount cadre-wise, and even some companies may reimburse honeymoon expenditures.
If you are in a continuous process, highly competitive industry, it's better to opt for a gift amount instead of any extra leave. However, call for a meeting with all the HODs, obtain inputs, discuss with the senior management, and finalize.