Dave,
Actually, 1800-2009 section 9.2.2.4 Sequential logic always_ff procedure says
"Variables on the left-hand side of assignments within an always_ff procedure,
including variables from the contents of a called function, shall not be written to by any other process.
Thus, the
“data_reg <= data_reg<< 1; // THIS DOESN’T WORK: data_reg is always 0.” is illegal.
Ben Cohen, Design and verification expert (310) 997-2187
http://www.systemverilog.us/ ben@systemverilog.us
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