General Description: If the shift register is described with separate signals for each register flip-flop, the "shreg_extract" attribute only works if it is set for all those signals. (A future enhancement will allow users to set the property on only one of the signals.)
NOTE: This problem is fixed in the 4.1i software release.
Attach the shreg_extract attribute to every signal.
: attribute shreg_extract : string; attribute shreg_extract of d1, d2, d3, d4, d5, d6, d7, d8 : signal is "no"; : : process(clk) begin if (clk'event and clk='1') then