mirror of https://github.com/xemu-project/xemu.git
36 lines
708 B
C
36 lines
708 B
C
/*
|
|
* Non-libc syscall hello world for Aarch64 BE
|
|
*
|
|
* SPDX-License-Identifier: GPL-2.0-or-later
|
|
*/
|
|
|
|
#define __NR_write 64
|
|
#define __NR_exit 93
|
|
|
|
int write(int fd, char *buf, int len)
|
|
{
|
|
register int x0 __asm__("x0") = fd;
|
|
register char *x1 __asm__("x1") = buf;
|
|
register int x2 __asm__("x2") = len;
|
|
register int x8 __asm__("x8") = __NR_write;
|
|
|
|
asm volatile("svc #0" : : "r"(x0), "r"(x1), "r"(x2), "r"(x8));
|
|
|
|
return len;
|
|
}
|
|
|
|
void exit(int ret)
|
|
{
|
|
register int x0 __asm__("x0") = ret;
|
|
register int x8 __asm__("x8") = __NR_exit;
|
|
|
|
asm volatile("svc #0" : : "r"(x0), "r"(x8));
|
|
__builtin_unreachable();
|
|
}
|
|
|
|
void _start(void)
|
|
{
|
|
write(1, "Hello World\n", 12);
|
|
exit(0);
|
|
}
|