I just need help understanding what each line in assembly code means. The instructions implement an n! factorial function.

Part4_Function ; Your Part 4 Code Here CMP RO, \#O; compare if ro =0 BEQ zero; when ro =0 is true MOV RI, RO; set ro rl or n= index loopl CMP RI, \# 1 ; checking if our index is equal to 1 BEQ endf SUBS RI, \#1 MUL RO, RO, R1 B loopl endf BX LR ; make sure the end of this section is aligned zero ADD RO, \#1 ; end of file