picorv32_pcpi_div: Compactify logic #216
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Overview
The current version of picorv32_pcpi_div can be compactified a bit:
Results
Current master, synthesized for iCE40:
With "idea 1" implemented:
With "idea 1" and "idea 2" implemented
Pitfalls
Given that formal verification shifts the quotient-mask by 5 positions, I generate the "finish" flag from bit-position 1 of the shift-register (the set bit should be located at positions 31, 26, 21, 16, 11, 6, 1). This is not tested.
The division unit passes the tests done with
make test
, though.