Investigate flaky test-arm-math-exp-regress-1376

https://ci.nodejs.org/job/node-test-commit-linux/8423/nodes=ubuntu1604_docker_alpine34-64/console

```console
not ok 1 parallel/test-arm-math-exp-regress-1376
  ---
  duration_ms: 0.240
  severity: crashed
  stack: |-
    oh no!
    exit code: CRASHED (Signal: 11)
```
