Optimizing pattern matching

We present improvements to the backtracking technique of pattern-matching c ompilation. Several optimizations are introduced, such as commutation of pa tterns, use of exhaustiveness information, and control flow optimization th rough the use of labeled static exceptions and context information. These o ptimizations have been integrated in the Objective-Caml compiler. They have shown good results in increasing the speed of pattern-matching intensive p rograms, without increasing final code size.