# simple example of placing return address ($ra) on the stack
# calculate the length of a string using a strlen like function

main:
	begin				# move frame pointer
	push	$ra			# save $ra onto stack

	la	$a0, string		# my_strlen("Hello");
	jal	my_strlen

	move	$a0, $v0		# printf("%d", i);
	li	$v0, 1
	syscall

	li	$a0, '\n'		# printf("%c", '\n');
	li	$v0, 11
	syscall

	pop	$ra			# recover $ra from stack
	end				# move frame pointer back

	li	$v0, 0			# return 0 from function main
	jr	$ra			#


my_strlen:				# length in t0, s in $a0
	li	$t0, 0
loop:					#
	lb	$t1, 0($a0)		# load *s into $t1
	beq	$t1, 0, end		#
	addi	$t0, $t0, 1		# length++
	addi	$a0, $a0, 1		# s++
	b	loop			#
end:
	move	$v0, $t0		# return length
	jr	$ra			#


	.data
string:
	.asciiz "Hello Andrew"