.equ STDOUT, 1
.equ SVC_WRITE, 64
.equ SVC_EXIT, 93

.text
.global _start

_start:
	stp x29, x30, [sp, -16]!
	mov x29, sp
	ldr x0, [sp, 24] // argv[0]
	bl _strlen // strlen(argv[0])
	mov x2, x0
	mov x0, #STDOUT
	ldr x1, [sp, 24]
	bl _write // write(stdout, argv[0], strlen(argv[0]))
	ldp x29, x30, [sp], 16
	mov x0, #0
	b _exit // exit(0);

// ssize_t _strlen(const char *str)
_strlen:
	mov x1, x0
	mov x0, #-1
1:	add x0, x0, #1
	ldrb w2, [x1, x0]
	cbnz x2, 1b
	ret

.text
//////////////// system call wrappers
// ssize_t _write(int fd, void *buf, size_t count)
_write:
	stp x29, x30, [sp, -16]!
	mov x8, #SVC_WRITE
	mov x29, sp
	svc #0
	ldp x29, x30, [sp], 16
	ret

// void _exit(int retval)
_exit:
	mov x8, #SVC_EXIT
	svc #0