It's not that easy, you also have to account for the pointer sizes (4 bytes instead of 8). Also alignment requirements are different on x32.

It's not only that either. OP used rdi because of calling convention, in x32 you would need to arguments on the stack instead and reference them +ebp instead of using registers if you want non-asm code to call your function.

x16, you mean :D

x32 is still amd64. Perhaps you meant x86 but see the other comments for that.