test/nop.asm

   1         bits 64
   2
   3         nop
   4         o64 nop
   5         pause
   6         o64 pause
   7
   8         xchg ax,ax
   9         xchg eax,eax
  10         xchg rax,rax
  11
  12         rep xchg ax,ax
  13         rep xchg eax,eax
  14         rep xchg rax,rax