and pad with cry. When it decoded cry, it printed a "TO DO" message.
http://bitsavers.org/pdf/mit/tx-0/memos/M-5001-19_macros_Apr60.pdf
derives a simple algorithm for cry. Implement that, remove the test
for cry from the pad code, and reformat the debug messages.
The same change appears in sim_instr and sim_opr_orig.