RFR: 8324121: SIGFPE in PhaseIdealLoop::extract_long_range_checks

[Roland Westrelin]

Both failures occur because `ABS(scale * stride_con)` overflows (scale
a really large long number). I reworked the test so overflow is no
longer an issue.

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Commit messages:
 - fix & test

Changes: https://git.openjdk.org/jdk/pull/18397/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=18397&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8324121
  Stats: 70 lines in 3 files changed: 61 ins; 0 del; 9 mod
  Patch: https://git.openjdk.org/jdk/pull/18397.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/18397/head:pull/18397

PR: https://git.openjdk.org/jdk/pull/18397