bits 64 push ax pop ax push rax pop rax push word 0x7F push dword 0x7FFF push qword 0x7FFFFFFF push word [rbx] pop word [rbx] push word [ebx] pop word [ebx] push qword [rbx] pop qword [rbx] push qword [ebx] pop qword [ebx] enter 0x10, 0x20 leave push fs pop fs push gs pop gs pushfw popfw pushfq popfq