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Further Synthesis Issues

There are many combinational circuits that have the same functionality.

Synthesis tools can accept additional guiding metrics from the user, that affect

(The basic algorithm in the additional material does not consider any guiding metrics.)

Gate libraries have high and low drive power forms of most gates (see later).

The tool will use Quine/McCluskey, Espresso or similar for logic minimisation.

   reg[31:0] y;
   if (e1) y <= e2; 
   else if (e3) y <= e4; 
   else y <= 32'bx;              // Note, assignment of 'x' permits automated logic minimisation.

Can share sub-expressions or re-compute expressions locally.

19: (C) 2008-12, DJ Greaves, University of Cambridge, Computer Laboratory.