# Simple recursive fibonacci implementation, roughly equivalent to:
#
#  int fibonacci (int arg)
#  {
#     if (arg < 2)
#       return arg
#     return fibonacci (arg-1) + fibonacci (arg-2)
#  }

# Initial state:
# stack: [arg]

# 0:
DUP
# stack: [arg, arg]

# 1:
PUSH_CONST 2
# stack: [arg, arg, 2]

# 2:
BINARY_COMPARE_LT
# stack: [arg, (arg < 2)]

# 3:
JUMP_ABS_IF_TRUE 13
# stack: [arg]

# 4:
DUP
# stack: [arg, arg]

# 5:
PUSH_CONST  1
# stack: [arg, arg, 1]

# 6:
BINARY_SUBTRACT
# stack: [arg,  (arg - 1)

# 7:
RECURSE
# stack: [arg, fib(arg - 1)]

# 8:
ROT
# stack: [fib(arg - 1), arg]

# 9:
PUSH_CONST  2
# stack: [fib(arg - 1), arg, 2]

# 10:
BINARY_SUBTRACT
# stack: [fib(arg - 1), arg,  (arg - 2)

# 11:
RECURSE
# stack: [fib(arg - 1), fib(arg - 1)]

# 12:
BINARY_ADD
# stack: [fib(arg - 1) + fib(arg - 1)]

# 13:
RETURN