retnq

386 and later

Return from Procedure Call

retnq | retnq imm16

RET, and its exact synonym RETN, pop IP or EIP from the stack and transfer control to the new address. Optionally, if a numeric second operand is provided, they increment the stack pointer by a further imm16 bytes after popping the return address.
RETF executes a far return: after popping IP/EIP, it then pops CS, and then increments the stack pointer by the optional argument if present.

Forms

Every form of retnq the assembler accepts, from NASM's own instruction table. The second column is the processor that introduced the form; a badge marks a form that needs an extension, that is lockable, or that long mode dropped.

Form	Since	Notes
retnq	386	long
retnq imm16	386	long