Did you do some standard debugging? Get a callstack of the crash, look at the logs, etc.
As you can see the regression test for memval_simple passes though it only runs the "nzcv" simple app. If you find corner cases not properly handled please consider contributing a better regression test.
http://139.178.82.61:8080/job/DynamoRIO-AArch64-Precommit/1577/consoleFull
171: Test command: /var/lib/jenkins/workspace/DynamoRIO-AArch64-Precommit/build/build_debug-internal-64/bin64/drrun "-s" "90" "-quiet" "-debug" "-killpg" "-stderr_mask" "0xC" "-dumpcore_mask" "0" "-code_api" "-c" "/var/lib/jenkins/workspace/DynamoRIO-AArch64-Precommit/build/build_debug-internal-64/api/samples/../bin/libmemval_simple.so" "--" "/var/lib/jenkins/workspace/DynamoRIO-AArch64-Precommit/build/build_debug-internal-64/suite/tests/bin/common.nzcv"
158/304 Test #171: code_api|sample.memval_simple ................................... Passed 0.33 sec