Split hardware mapping from `fifo.ys` into `fifo_map.ys`. Reduces size of `fifo.out` log and allows separate yosys calls in the makefile.
Some tidy up and minor changes in `fifo.ys` for better discussion.
Filled out note on `clean` (changed from `opt_clean`) and introduced `;;`.
Highlighted `$memrd` and added a paragraph about it.
More detail on the flatten and merging of `fifo_reader` block.
Brief discussion on the changes from `$memrd` to `$memrd_v2`.
Split coarse grain representation into 4 parts, loosely: fsm/opt, other optimizations/techmap/memory_dff, DSPs, alumacc/memory -nomap.
Split hardware mapping into subsections as well: memory blocks (map_ram and map_ffram), arithmetic (map_gates), FFs (map_ffs), LUTs (map_luts and briefly abc), and other (map_cells and a note on hilomap and iopadmap).
Also add `-T` flag to Yosys call to remove footer from log output.
Fifo code based on SBY quick start.
Instead of showing the full design we are (currently) focusing on a single output (rdata), using `%ci*` to get the subcircuit it relies on.