Prohibiting use of some registers in the GCC compiler

[Nisal Menuka]

Hi,
I would like to reserve some registers in ARM64 processor and prohibit
the compiler from using them in any scenario.

For example: ARM64 Thirty-one 64-bit general-purpose registers X0-X30.
I want to reserve register X30, and make sure when I compile any code
using gcc, it won't use register X30 in any situation.

How can this be done? Any help would be greatly appreciated.

Thanks,
Nisal