To get a 64 bit value of location pointed by RIP register use:
mov rax,[rip]
To get the address pointed by RIP register use:
lea rax,[rip]
here is how you can use RIP:
displacement EQU 200h
mov ah,[rip]
mov rax,[rip+3]
mov rax,[rip+400h]
mov cx,[rip+128]
mov [rip+127],cx
mov [rip+displacement],rbx
mov rbx,[rip+displacement]
mov rax,[rip]
mov [rip+1],sil
cmp byte ptr [rip], 90h
lea rbx,[rip]
lea rax,[rip+2]
call qword ptr[rip+400]
push [rip]
push [rip+80h]
pop [rip]