more user-friendly TLDumper

lsq: use reg to keep track of the number of valid entries

roq: use reg to keep track of the number of valid entries

dpq: use reg to keep track of the number of valid entries

Coverage

this greatly accelerates compilation.

Fix source d uncached get bypass

redirect: add RedirectLevel to simplify flush logic

emu: change exit code

This works for linux-hello which never stops.
Now, we can stop emu with sigint and still get a valid coverage result.