.text
isIdent:

	# set up stack frame
	addi	$sp, $sp, -4
	sw	$fp, ($sp)	# push $fp
	la	$fp, ($sp)
	addi	$sp, $sp, -4
	sw	$ra, ($sp)	# push $ra
	addi	$sp, $sp, -4
	sw	$s0, ($sp)	# push $s0 #row
	addi	$sp, $sp, -4
	sw	$s1, ($sp)	# push $s1 #col
	addi	$sp, $sp, -4
	sw	$s2, ($sp)	# push $s2
	addi	$sp, $sp, -4
	sw	$s3, ($sp)	# push $s3

	move	$s0, $a0
	move	$s1, $a1

is_row_init:
	li	$s2, 0		# row = 0
is_row_cond:
	bge	$s2, $s1, is_row_f	# row < n  ||  row >= n
	nop	#[branch delay]

is_col_init:
	li	$s3, 0		# col = 0
is_col_cond:
	bge	$s3, $s1, is_col_f	# col < n  ||  col >= n
	nop	#[branch delay]

	# m[row][col] = *(&m[0][0] + (row * N) + col)
	mul	$t0, $s2, $s1	# % <- row * N
	add	$t0, $t0, $s3	#    + col
	li	$t1, 4
	mul	$t0, $t0, $t1	#    * sizeof(word)
	addu	$t0, $s0, $t0	#    + &m[0][0]

## if m[r][c] != 1
m_if_1:
	bne $t0, 1, row_if_1

## if m[r][c] != 0
m_if_2:
	bnez $t0, row_if_2
	j is_col_step

## if row = col
row_if_1:
	beq $s2, $s3, return_0
	j is_col_step

## if row != col
row_if_2:
	bne $s2, $s3, return_0

is_col_step:
	addi	$s3, $s3, 1	# col++
	j	is_col_cond
	nop	#[branch delay]
is_col_f:

is_row_step:
	addi	$s2, $s2, 1	# row++
	j	is_row_cond
	nop	#[branch delay]
is_row_f:

base:
	li $v0, 1
	j go_back

return_0:
	li $v0, 0
	j go_back

go_back:
	lw	$s3, ($sp)	# pop $s3
	addi	$sp, $sp, 4
	lw	$s2, ($sp)	# pop $s2
	addi	$sp, $sp, 4
	lw	$s1, ($sp)	# pop $s1
	addi	$sp, $sp, 4
	lw	$s0, ($sp)	# pop $s0
	addi	$sp, $sp, 4
	lw	$ra, ($sp)	# pop $ra
	addi	$sp, $sp, 4
	lw	$fp, ($sp)	# pop $fp
	addi	$sp, $sp, 4
	jr	$ra