What does this Assembly snippet output?

1.global _main
2.align 2
3_main:
4    stp x29, x30, [sp, #-16]!
5    mov w19, #1
61:
7    sub sp, sp, #16
8    str x19, [sp]
9    adrp x0, fmt@PAGE
10    add x0, x0, fmt@PAGEOFF
11    bl _printf
12    add sp, sp, #16
13    lsl w19, w19, #1
14    cmp w19, #16
15    blt 1b
16    ldp x29, x30, [sp], #16
17    mov w0, #0
18    ret
19.section __TEXT,__cstring
20fmt: .asciz "%d\n"