Hi All

I was building a complex multiplier into my HDL code, and noticed it was
beginning to look like the Xilinx block.

Looking at the documentation of the latter, I notice there is a latency
overhead associated with blocking behaviour. This would appear to be due
to buffering. I offer an unbuffered version here for criticism, it has a
latency overhead, in blocking mode, of zero, but note, is still a piece
of brainstorming, not validated IP.

I created it out of a general curiosity about blocking in a system with
inputs, a pipelined function, and an output. The clock for the
processing engine is enabled only if both inputs have tready asserted.
An input is ready only if the output tready signal is asserted, and all
inputs have valid data. The output tvalid signal is forwarded from one
of the inputs, the logic ensuring that these are all identical. It is
maintained, until acknowledged by an output tready.

Protocol failure will break this block, inputs must have assured tvalid
behaviour.

Best regards
Geoff