Lab7-Assignment4.asm

#Laboratory Exercise 7, Assignment 4
.data
Message: .asciiz "Ket qua tinh giai thua la: "
.text
main: jal WARP
 
print: 
	add $a1, $v0, $zero 	# $a1 = result from N!
 	li $v0, 56
 	la $a0, Message
 	syscall
	quit: li $v0, 10 	#terminate
	syscall 
endmain:
WARP: 
	sw $fp,-4($sp) 		#save frame pointer (1)
 	addi $fp,$sp,0 		#new frame pointer point to the top (2)
 	addi $sp,$sp,-8 	#adjust stack pointer (3)
 	sw $ra,0($sp) 		#save return address (4)
 	li $a0,3 		#load test input N
 	jal FACT 		#call fact procedure
 	nop 
 
 	lw $ra,0($sp) 		#restore return address (5)
 	addi $sp,$fp,0 		#return stack pointer (6)
 	lw $fp,-4($sp) 		#return frame pointer (7)
 	jr $ra 
wrap_end:
FACT: 
	sw $fp,-4($sp) 		#save frame pointer 
 	addi $fp,$sp,0 		#new frame pointer point to stack’s 
top:
 	addi $sp,$sp,-12 	#allocate space for $fp,$ra,$a0 in 
stack: 
 	sw $ra,4($sp) 		#save return address
 	sw $a0,0($sp) 		#save $a0 register
 
 	slti $t0,$a0,2 		#if input argument N < 2
 	beq $t0,$zero,recursive	#if it is false ((a0 = N) >=2) 
 	nop
 	li $v0,1 		#return the result N!=1
 	j done
 	nop
recursive: 
 	addi $a0,$a0,-1 	#adjust input argument
 	jal FACT 		#recursive call 
	nop 
 	lw $v1,0($sp) 		#load a0
 	mult $v1,$v0 		#compute the result
 	mflo $v0
done: 
	lw $ra,4($sp) 		#restore return address
 	lw $a0,0($sp) 		#restore a0
 	addi $sp,$fp,0 		#restore stack pointer
 	lw $fp,-4($sp) 		#restore frame pointer
 	jr $ra 			#jump to calling
fact_end: