Avoid single expensive test in 530-checker-loops.

Rationale:
All tests run in "no time", except one instance
that iterates over full iteration space before
going OOB. Protect that instance with a HEAVY
boolean to avoid timing out in interpretation mode.

Impact on interpreted runtime:

1m6.936s   ->   0m0.031s

Change-Id: I413939b683c76b7be0f1259da8533d4b069eac6d