What does this op amp circuit do?
Most likely, this is intended to provide variable brightness in the LED without dissipating much power. It cannot be a current source, since there is no current sense resistor, which would normally be inserted between the FET source and ground. The amp using pins 12-14 is clearly set up as a comparator, and if it were fed a triangle or sawtooth wave to pin 12 would produce a PWM signal at the gate of the FET, modifying its brightness by turning the pot.

However, the rest of the circuit is incomprehensible, and should not produce anything useful. At the very least, tieing pin 3 to +12 ensures that the output will not change, and neither will the output on pin 7. I also doubt the two resistors in series between pins 9 and 12. 

I suspect you need to go back and have another go at tracing your connections.