Koios Benchmarks Failing With Flat Routing

[nedsels]

With flat routing on, seemingly all koios_medium benchmarks fail. There are always some number of overused nodes.

Steps to Reproduce

I have created a new branch with a new regression test that is identical to regression_tests/vtr_reg_nightly_test4/koios_medium, except it includes --flat_routing on as an argument.

1. Checkout this branch.
2. Navigate to vtr_flow/tasks
3. Run ../scripts/run_vtr_task.py regression_tests/vtr_reg_nightly_test4/koios_medium_flat_routing

vpr should fail with exit code 2.

Your Environment

• VTR revision used: commit 3f2b9e8f2c4acc05cc3ab6884235fd4896777236 (I noticed this bug in earlier commits on the master branch)
• Operating System and version: Ubuntu 18.04.6 LTS (wintermute)
• Compiler version: gcc version 9.4.0 (wintermute)

[vaughnbetz]

This regtest doesn't seem to have the command line option to turn on choke point resolution. Neither do other flat routing tests. @amin1377 : shouldn't it be on?

script_params=-track_memory_usage -crit_path_router_iterations 100 --route_chan_width 300 --flat_routing on