RFR: 8354767: Test crashed: assert(increase < max_live_nodes_increase_per_iteration) failed: excessive live node increase in single iteration of IGVN: 4470 (should be at most 4000)

[Daniel Lundén]

Certain idealizations introduce more new nodes than expected when adding the new assert in the changeset for [JDK-8351833](https://bugs.openjdk.org/browse/JDK-8351833). The limit checked by the new assert is too optimistic.

### Changeset

Tweak the maximum live node increase per iteration in the main IGVN loop from `NodeLimitFudgeFactor * 2` (4000 by default) to `NodeLimitFudgeFactor * 3` (6000 by default). This change does not only affect the newly added assert in [JDK-8351833](https://bugs.openjdk.org/browse/JDK-8351833), but also the IGVN live node count bailout which is `MaxNodeLimit` minus the maximum live node increase per iteration. That is, the bailout by default is currently at 80000 - 4000 = 76000 live nodes, and 80000 - 6000 = 74000 live nodes after this changeset. In practice, the difference does not matter (see Testing below).

The motivation for just tweaking the limit and keeping the assert added by [JDK-8351833](https://bugs.openjdk.org/browse/JDK-8351833) is that individual IGVN transformations (within a single iteration of the IGVN loop) should, in theory, only affect a local set of nodes in the ideal graph. Therefore, the assert is a good sanity check that various transformations (current ones and whatever we might add in the future) do not scale in the size of the ideal graph (i.e., they are local transformations).

I have not managed to construct a reliable regression test, as triggering the assert is difficult (highly intermittent). Also, the issue is benign (a too optimistic limit).

### Testing

- [GitHub Actions](https://github.com/dlunde/jdk/actions/runs/14594986152)
- `tier1` to `tier4` (and additional Oracle-internal testing) on Windows x64, Linux x64, Linux aarch64, macOS x64, and macOS aarch64.
- Checked IGVN live node count bailouts in DaCapo, Renaissance, SPECjvm, and SPECjbb and observed no bailouts before nor after this changeset.

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Commit messages:
 - Fix issue

Changes: https://git.openjdk.org/jdk/pull/24960/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=24960&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8354767
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/24960.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/24960/head:pull/24960

PR: https://git.openjdk.org/jdk/pull/24960