What does this log?

1.global _main
2.align 2
3_main:
4    stp x29, x30, [sp, #-32]!
5    mov x8, #0xFFFFFFFFFFFFFFFF
6    mov w8, #1
7    sub sp, sp, #16
8    str x8, [sp]
9    adrp x0, fmt@PAGE
10    add x0, x0, fmt@PAGEOFF
11    bl _printf
12    add sp, sp, #16
13    ldp x29, x30, [sp], #32
14    mov w0, #0
15    ret
16.section __TEXT,__cstring
17fmt: .asciz "%lld\n"