# A live coding example done as a recap on functions.
# This has a simple function with 1 parameter and a return value

	.data
msg_sum1:
	.asciiz "Sum 1.. "
msg_sum2:
	.asciiz " = "

	.text
main:
	# $s0 used for max since we set it before doing the jal
	# but need it again after the jal
	# If a function uses $s0 that same function must
	# push it to the stack and pop it to restore it later
	
	# $t0 was used for result since we are not doing another
	# jal after we set its value so we do not need to worry
	# about it getting overwritten by another function
main__prologue:
	push	$ra
	push	$s0
main__body:
	li	$s0, 10			# int max = 10;
	move	$a0, $s0		# int max = 10;
	jal	sum_to			# result = sum_to(max);
	move	$t0, $v0		# $t0 = result
	
	li	$v0, 4			# printf("Sum 1.. ");
	la	$a0, msg_sum1
	syscall
	
	li	$v0, 1			# printf("%d",max);
	move	$a0, $s0
	syscall
	
	li	$v0, 4			# printf(" = ");
	la	$a0, msg_sum2
	syscall
	
	li	$v0, 1			# printf("%d", result);
	move	$a0, $t0
	syscall
	
	li	$v0, 11			# putchar('\n')
	li	$a0, '\n'
	syscall
	
	li	$v0, 0
main__epilog:
	pop	$s0
	pop	$ra 
	jr 	$ra


sum_to:
sum_to__prologue:
sum_to__body:
	li	$t0, 0			# sum = 0
	li	$t1, 1			# i = 1

sum_to__while:
	bgt	$t1, $a0, sum_to__while_end # while (i <= n) 
	add	$t0, $t0, $t1		# sum = sum + i
	addi	$t1, $t1, 1		# i++
	j	sum_to__while
sum_to__while_end:

	move	$v0, $t0		# return sum
sum_to__epilog:
	jr	$ra