RFR: 8329203: Parallel: Investigate Mark-Compact for Full GC to decrease memory usage

[Albert Mingkun Yang]

Refactor Parallel full-gc to use the same algorithm (mark-compact) as Serial and G1 full-GC. This removes the obj-end bitmap. When GC threads are few, the old implementation can be more efficient because it requires fewer heap iterations. The new full-GC implementation, on the other hand, is more scalable because it introduces more phases (`forward_to_new_addr` and `adjust_pointers`) that can partition work effectively.

The diff is rather large, so reading the new code directly from `invoke_no_policy` is probably easier.

Test: tier1-6; some improvement in Dacapo-h2, CacheStresser, but no difference in specjbb2015, specjvm2008.

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Commit messages:
 - pgc-full-gc

Changes: https://git.openjdk.org/jdk/pull/19101/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=19101&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8329203
  Stats: 1532 lines in 9 files changed: 415 ins; 1023 del; 94 mod
  Patch: https://git.openjdk.org/jdk/pull/19101.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/19101/head:pull/19101

PR: https://git.openjdk.org/jdk/pull/19101