 
   July 1, 1994                                                        SIS(1)
 
   buffer_opt [-l #] [-f #] [-c] [-d] [-T] [-L] [-v #] [-D] node-list
 
     Builds fanout trees for the nodes in the node-list.  If no nodes are
     specified selects the nodes to be buffered in order to improve perfor-
     mance of the entire network. The network is assumed to be mapped.
 
     The -l # option specifies the number of fanouts which a node can have so
     as to be eligible for buffering. The default is 2, hence any multi-
     fanout node is a candidate for buffering.
 
     The -f # option specifies the transformations to use. Set the three
     least significant bits indicate the use (value == 1) of the transforma-
     tions. xx1 to use the repower transformation, x1x to use an unbalanced
     transformation and 1xx to use the balanced distribution of signals. More
     than one transformation can be set active. Thus to allow the algorithm
     full flexibility use the value = 7 (111 in binary notation) which is
     also the default.
 
     The -c option specifies that one pass be carried out.  The default is to
     iterate till no improvement is achieved.
 
     The -d option allows the complex gates to be decomposed into smaller
     ones so as to increase drive capability. By default the complex gates
     are retained.
 
     The -L option traverses the network from outputs to inputs ensuring that
     for every node, the gate that implements it does not drive a load
     greater than the max_load limit specified for that gate. THIS OPTION IS
     NOT YET IMPLEMENTED.
 
     The -T option displays the circuit performance as the iterations pro-
     gress. If the required times at the outputs are not specified the cir-
     cuit delay is shown, else the minimum slack value is displayed.
 
     The -v #,-D option are for debugging. The -v # option is the most ver-
     bose and the amount of verbosity can be increased by letting the argu-
     ment for -v range from 1 to 100.
 
                                                                            1
