An apparatus and method for synchronizing parallel processors utilizing a lookahead synchronization circuit is provided by the present invention. A five gate logic circuit is formed as a cell and this cell can serve as a node in a tree logic operation circuit. The tree is capable of realizing a variety of fetch-and-operation, priority and operation-and-broadcast primitives and the cell can serve in a carry circuit of a binary adder. The tree may be pruned at any point and the circuit will continue to function for those nodes remaining in the tree. Processing elements are attached to leaf nodes of the tree. The present invention is capable of realizing the fetch-and-exclusive-OR, fetch-and-add, fetch-and-AND, fetch-and-OR, fixed priority sch...