RFR: Fix overflow of integer

[Symious]

This ticket is to fix the overflow issue of Integer, which is causing the `measureRight` benchmark to fail.

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Commit messages:
 - Fix overflow of integer

Changes: https://git.openjdk.org/jmh/pull/167/files
  Webrev: https://webrevs.openjdk.org/?repo=jmh&pr=167&range=00
  Stats: 2 lines in 2 files changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jmh/pull/167.diff
  Fetch: git fetch https://git.openjdk.org/jmh.git pull/167/head:pull/167

PR: https://git.openjdk.org/jmh/pull/167