.text .globl mystart mystart: #if defined(__x86_64__) pushq $0 mov %rsp, %rbp andq $0xfffffffffffffff0, %rsp movl $42, %edi movl $0x2000001, %eax movl $0, %ecx movq %rcx, %r10 syscall jmp 1f 1: hlt nop nop nop nop #elif defined(__i386__) pushl $0 mov %esp, %ebp andl $0xfffffff0, %esp subl $12, %esp pushl $42 mov $0x40001, %eax call _sysenter_trap jmp 1f 1: hlt nop nop nop nop _sysenter_trap: pop %edx mov %esp, %ecx sysenter nop #else #error Unsupported architecture #endif