* @param b1 Block of state 1
* @param b2 Block of state 2
* @return if the blocks are known to be matching
* @param b1 Block of state 1
* @param b2 Block of state 2
* @return if the blocks are known to be matching
* @param b1 Block of state 1
* @param f1 Fragment of state 1
* @param b2 Block of state 2
* @param b1 Block of state 1
* @param f1 Fragment of state 1
* @param b2 Block of state 2