how does loop unroll work in hdl coder?

these are matlab resource report generated --more hardware is without loop unroll & less hardware is with loop unroll

Answer 1

[Kiran Kintali]

These HDL Coder documentation files should explain the behavior.

https://www.mathworks.com/help/hdlcoder/ref/coder.hdl.loopspec.html

https://www.mathworks.com/help/hdlcoder/ug/loop-best-practices-for-hdl-code-generation.html

The coder.hdl.loopspec('unroll') pragma transforms loops by creating multiples copies of the loop body in the RTL design, which allows some or all loop iterations to occur in parallel.

coder.hdl.loopspec('stream') generates a single instance of the loop body in the HDL code and generates additional state machine logic necessary to share the loop body.