# 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:					# while (s[length] != 0) {
	add	$t1, $a0, $t0		#   calculate &s[length]
	lb	$t2, 0($t1)		#   load s[length] into $t2
	beq	$t2, 0, end		#
	addi	$t0, $t0, 1		#   length++;
	b	loop			# }
end:
	move	$v0, $t0		# return length
	jr	$ra			#


	.data
string:
	.asciiz "Hello"