#include <avr/io.h>
#define FRAME_SIZE 8

    .section .text
;
    .global copy_layer
    .type copy_layer, @function
copy_layer:
    movw X, r24         ; Source frame.
    movw Z, r22         ; Target frame.
    ldi  r24, FRAME_SIZE*2 ; Number of iterations needed.

copy:
    ld   r0, X+
    st   Z+, r0
    dec  r24
    brne copy

    ret


    .global push_layer
    .type push_layer, @function
push_layer:
    movw X, r24         ; Source frame.
    movw Z, r22         ; Target frame.
    ldi  r24, FRAME_SIZE ; Number of iterations needed.

push:
    ldd  r0, Z+1
    st   Z+, r0
    ld   r0, X+
    st   Z+, r0
    dec  r24
    brne push

    ret