gistfile1.txt

// This code should align the stack to a 16 byte boundary for OSX function calls

push rbx          // save rbx. joe says rbx is caller saved, but other things say its callee-saved?
mov rdx, 0        // move 0 into the first division register
mov rax, rsp      // move rsp's address into the second division register
mov rbx, 16       // move the divisor, 16, into rbx
div rbx           // perform the division using the value we just put into rbx  
mov rbx, rdx      // store the remainder into rbx so we have it when we return
subq rsp, rbx     // grow the stack pointer by our offset
callq 0xdeadbeef  // call out to the function
addq rsp, rbx     // put the stack pointer back where it was
pop rbx           // restore rbx