RFR: 8287550: Improve stack bang sp update granularity

[ldaxr]

Align sp to page boundary when set to growth watermark in interpreter.

The performance tests for a JMH case are shown below.
[stack_bang_sp_align.csv](https://github.com/openjdk/jdk/files/8803249/stack_bang_sp_align.csv)

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Commit messages:
 - Enhance interpreter stack bang

Changes: https://git.openjdk.java.net/jdk/pull/8951/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=8951&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8287550
  Stats: 7 lines in 2 files changed: 7 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8951.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8951/head:pull/8951

PR: https://git.openjdk.java.net/jdk/pull/8951