add

section01/Lec15/fact_inclass.s

+.text
+	li	$a0, 10
+	jal	fact
+	
+	move 	$s0, $v0
+	li	$v0, 10
+	syscall
+
+fact:
+	addi $sp, $sp, -12 #Allocate space for return, arg, result
+	sw $ra, 0($sp)
+	sw $a0, 4($sp)
+	li $t0, 1
+	bge $a0, $t0, ELSE	#If arg >= 1
+	sw $t0, 8($sp)
+	j END
+ELSE:
+	addi $a0, $a0, -1	#n-1
+	jal fact
+	lw $a0, 4($sp)		#Load arg
+	mul $t0, $a0, $v0	# t0 = arg * returnValue
+	sw $t0, 8($sp)		# result = t0
+END:
+	lw $v0, 8($sp)		#Set return register = return
+	lw $ra, 0($sp)		#Load return address
+	addi $sp, $sp, 12	#Deallocate stack
+	jr $ra			
\ No newline at end of file