[jdk17u-dev] RFR: 8274632: Possible pointer overflow in PretouchTask chunk claiming

[Aleksey Shipilev]

Clean backport to improve pre-touching reliability. There is no recorded bugtail for 2 years.

Additional testing:
 - [x] macos-aarch64-server-fastdebug, `hotspot:tier1`

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Commit messages:
 - Backport a914ee72167f642b76b1c1cdddd7ff0698d061cc

Changes: https://git.openjdk.org/jdk17u-dev/pull/2047/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=2047&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8274632
  Stats: 11 lines in 2 files changed: 1 ins; 4 del; 6 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/2047.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/2047/head:pull/2047

PR: https://git.openjdk.org/jdk17u-dev/pull/2047