.nop [size]This directive emits no-op instructions. It is provided on all architectures,
allowing the creation of architecture neutral tests involving actual code. The
size of the generated instruction is target specific, but if the optional
size argument is given and resolves to an absolute positive value at that
point in assembly (no forward expressions allowed) then the fewest no-op
instructions are emitted that equal or exceed a total size in bytes.
.nop does affect the generation of DWARF debug line information.
Some targets do not support using .nop with size.