Describe the function of the following recursive subroutine. In order forthis subroutine to work correctly what should be the minimum stack size? SUB STR LR, [SP, -4! STR RO, ISP,+-4]! MOVS RO, RO, l.SR #1 ADDC3 R-, R1 , # 1 BLNE SUB LDR R0 , [SP] , #4 LDR PC,SPI,#4 Describe the function of the following recursive subroutine. In order forthis subroutine to work correctly what should be the minimum stack size? SUB STR LR, [SP, -4! STR RO, ISP,+-4]! MOVS RO, RO, l.SR #1 ADDC3 R-, R1 , # 1 BLNE SUB LDR R0 , [SP] , #4 LDR PC,SPI,#4