 
   July 1, 1994                                                        SIS(1)
 
   decomp [-gqd] [node-list]
 
     Decompose all the nodes in the node-list.  If the node-list is not
     specified, all the nodes in the current network will be decomposed.
     Decompostion will factor nodes and make the divisor a new node within
     the network, re-expressing other nodes in terms of this newly introduced
     node.  It is one of the transforms used to break down large functions
     into smaller pieces, usually at the cost of introducing a few more
     literals.
 
     If the -q option (the default) is specified, the quick decomp algorithm
     is used which extracts out an arbitrary kernel successively.  Because of
     the fast algorithm for generating an arbitrary kernel, decomp -q is very
     fast compared with the decomp -g.  In most cases, the result is very
     close.  This command is recommended at the early phase of the optimiza-
     tion.
 
     If the -g option is specified, the good decomp algorithm is used which
     successively extracts out the best kernel until the function is factor
     free, and applies the same algorithm to all the kernels just extracted.
     This operation will give the best algebraic decomposition for the nodes.
     But, since it generates all the kernels at each step, it takes more CPU
     time.  In general, decomp -q should be used in the early stage of the
     optimization. Only at the end of the optimization, should decomp -g be
     used.
 
     If the -d option is specified, the disjoint decomposition is performed.
     Currently, the disjoint decomposition is limited to the following simple
     algorithm:  It partitions the cubes into sets of cubes having disjoint
     variable support, creates one node for each partition, and a node (the
     root of the decomposition) which is the OR of all the partitions.
 
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