nop

No Operation

NOP

Does nothing. Used for padding or timing.

Pseudocode Operation

# No operation performed
PC ← PC + 4

Encoding

Binary Layout

11010101000000110010

31:12

0000

11:8

000

7:5

11111

4:0

 

Format System Alias

Opcode 0xD503201F

Extension Base

Operands

Related

Other forms of nop

• nop No Operation (Thumb)
• nop No Operation (A32)

Across architectures

No Operation : how x86, ARM, RISC-V, and PowerISA each do this.

More in Base

Reference

View in Arm A64 ISA Reference ↗ Arm A64 ISA

Instruction Forms

Encoding	Instruction		ISA		Bit pattern
0xD503201F	NOP		A64		11010101000000110010 | 0000 | 000 | 11111

Description

No Operation does nothing, other than advance the value of the program counter by 4. This instruction can be used for instruction alignment purposes.

Operation

return;    // do nothing