Post RTL synthesis we have a netlist and can use Rent for wire lengths provided sufficient hierarchy exists (perhaps five or more levels). We can either use the natural hierarchy of the RTL input design or we can apply a clustering/clique finding algorithms to determine a rough placement floorplan without doing a full place and route.
Pre RTL synthesis we can readily collect the following certainties (and hence the static power (ignoring drive strength selection))
module CTR16( input mainclk, input din, input cen, output o); reg [3:0] count, oldcount; // D-types always @(posedge mainclk) begin if (cen) count <= count + 1; // ALU if (din) oldcount <= count; // Wiring end assign o = count[3] ^ count[1]; // Combinational endmodule
But the following dynamic quantities require heuristic estimates:
38: (C) 2008-17, DJ Greaves, University of Cambridge, Computer Laboratory. |