RFR: 8376839: GenShen: Improve performance of evacuations into the old generation [v4]

[William Kemper]

> When GenShen evacuates an object into the old generation, it also dirties the card for that object and updates the offsets of the first and last object in the card. In many cases, the same card may dirtied repeatedly and the object starts updated unnecessarily. We can reduce the total amount of work by moving these operations into a separate phase of the cycle which allows them to be batched.

William Kemper has updated the pull request incrementally with one additional commit since the last revision:

  Avoid update call when there is no work to be done

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Changes:
  - all: https://git.openjdk.org/jdk/pull/29511/files
  - new: https://git.openjdk.org/jdk/pull/29511/files/f905138c..e29d3d4e

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=29511&range=03
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=29511&range=02-03

  Stats: 3 lines in 1 file changed: 2 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/29511.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/29511/head:pull/29511

PR: https://git.openjdk.org/jdk/pull/29511