Passing argument to functions is simple when you have four or fewer non-floating-point arguments. You use rcx, rdx, r8, and r9 and provide shadow space on the stack before calling the function. After the call, you re-adjust the stack for the shadow space, and everything is fine. If you have more than four arguments, things are more complicated.
Using More Than Four Arguments
Let’s first see why things get complicated with more than four non-floating-point arguments, as shown in Listing 41-1.
; arguments1.asm
extern printf
section .data
first db "A",0
second db "B",0 ...
