ArithmeticMIPS/nestedFunctions.asm at master · danielhcg/ArithmeticMIPS · GitHub

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#Nested Functions

.data

	newLine: .asciiz "\n"
	test: .asciiz "test"

.text

	#Main function
	main:

		addi $s0, $zero, 63

		jal displayValue

		#Prints a new line
		li $v0, 4
		la $a0, newLine
		syscall

		#'Declaring' a value
		addi $s0, $zero, 10

		#Calling function to increase value in register s0 and display
		jal increaseMyRegister

		#Prints a new line
		li $v0, 4
		la $a0, newLine
		syscall

		#Calling function to display original value
		jal displayValue

	#Closing statement for main function
	li $v0, 10
	syscall

	#Function to increase value in register s0
	increaseMyRegister:

		#Nested function here returns to main, but we want it to return to
		#increaseMyRegister function. Need to save the old address to the stack.

		#Freeing up 8 bytes of memory in stack for or old value in s0 and
		#for the old address from main
		addi $sp, $sp, -8

		#Storing value in stack
		sw $s0, 0($sp)

		#Storing address
		sw $ra, 4($sp)

		#Manipulate value in register
		addi $s0, $s0, 30 #30 + value in s0, stored in s0

		#Nested function
		jal displayValue

		#Load original value and address from memory to be accessible in main
		lw $s0, 0($sp)
		lw $ra, 4($sp)
		addi $sp, $sp, 4  #Restoring the stack

	#Closing statement, returns to main
	jr $ra

	#Function to decrease value in register s1

	#Function to print value in register
	displayValue:

		li $v0, 1
		move $a0, $s0
		syscall

	#return to the caller
	jr $ra