awk '
BEGIN	{
	labnum = 0
	}
/^ bne /	{
	/* Normalize operand order */
	a = $2
	b = $3
	if (b > a) {
		a = $3
		b = $2
	}
	if (a == b) {
		/* Unconditional branch? */
		print " li $32, " $4
		print " jr $32"
	} else if (b == "$0,") {
		/* bne 0 is jt */
		print " jt " a " " $4
	} else {
		/* bne a b is really xor jt */
		print " xor $32, " a " " substr(b, 1, length(b)-1)
		print " jt $32, " $4
	}
	next
	}
/^ beq /	{
	/* Normalize operand order */
	a = $2
	b = $3
	if (b > a) {
		a = $3
		b = $2
	}
	if (a == b) {
		/* Unconditional branch? */
		print " li $32, " $4
		print " jr $32"
	} else if (b == "$0,") {
		/* beq 0 is jf */
		print " jf " a " " $4
	} else {
		/* bne a b is really xor jt */
		print " xor $32, " a " " substr(b, 1, length(b)-1)
		print " jf $32, " $4
	}
	next
	}
/^ (j|b) /	{
	if ((substr($2, 1, 1) == "$") && (substr($2, 1, 2) != "$L")) {
		/* Mutant form, really jr */
		print " jr " $2
	} else {
		print " li $32, " $2
		print " jr $32"
	}
	next
	}
/^ jal / {
	print " .ret L_" labnum
	print " la $31, L_" labnum
	print " la $32, " $2
	print "L_" labnum ":"
	++labnum
	next
	}
/^ jalr / {
	print " .ret L_" labnum
	print " la $31, L_" labnum
	print " jr " $2
	print "L_" labnum ":"
	++labnum
	next
	}
/^/	{
	print $0
	}
'