x86 Instruction Set Reference

NOP

No Operation

Opcode Mnemonic Description
90 NOP No operation.
Description

Performs no operation. This instruction is a one-byte instruction that takes up space in the instruction stream but does not affect the machine context, except the EIP register.

The NOP instruction is an alias mnemonic for the XCHG (E)AX, (E)AX instruction.
Flags affected

None.

Exceptions
None.
Instruction Latency Throughput Execution Unit
CPUID0F3n/0F2n0F3n/0F2n0F2n
NOP1/0.50.5/0.5ALU