[bits 64]
xchg ax, ax
xchg ax, bx
xchg bx, ax
xchg eax, eax
xchg eax, ebx
xchg ebx, eax
xchg rax, rax
xchg rax, rbx
xchg rbx, rax

xchg al, al
xchg al, r8b
xchg r8b, al

xchg ax, ax
xchg ax, r8w
xchg r8w, ax
xchg ax, r9w
xchg r9w, ax

xchg eax, eax
xchg eax, r8d
xchg r8d, eax
xchg eax, r9d
xchg r9d, eax

xchg rax, rax
xchg rax, r8
xchg r8, rax
xchg rax, r9
xchg r9, rax