[jdk19] RFR: 8289069: Very slow C1 arraycopy jcstress tests after JDK-8279886 [v2]

[Igor Veresov]

> I used `BlockBegin::number_of_blocks()` to size the bitmaps, however that is a total number of blocks. Since `mark_loops()` is called after every inlining (for every inlinee - no need to reanalyze the whole method), the bitmaps get progressively larger, and have to be zeroed. That makes the complexity quadratic. The solution is to appropriately size the bitmaps and keep the whole thing linear. Tests look good.

Igor Veresov has updated the pull request incrementally with one additional commit since the last revision:

  Fix a typo

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Changes:
  - all: https://git.openjdk.org/jdk19/pull/72/files
  - new: https://git.openjdk.org/jdk19/pull/72/files/6f20dec2..8abfae6e

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk19&pr=72&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk19&pr=72&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk19/pull/72.diff
  Fetch: git fetch https://git.openjdk.org/jdk19 pull/72/head:pull/72

PR: https://git.openjdk.org/jdk19/pull/72