RFR: 8347009: Speed ​​up parseInt and parseLong [v14]

[Shaojin Wen]

> This is an optimization for decimal Integer.parseInt and Long.parseLong, which improves performance by about 10%. The optimization includes:
> 1. Improve performance by parsing 2 numbers at a time, which has performance improvements for numbers with length >= 3.
> 2. It uses charAt(0) for the first number. Assuming that the optimization can eliminate boundary checks, this will be more friendly to parsing numbers with length 1.
> 3. It removes the reliance on the Character.digit method and eliminates the reliance on the CharacterDataLatin1#DIGITS cache array, which avoids performance degradation caused by cache misses.

Shaojin Wen has updated the pull request incrementally with two additional commits since the last revision:

 - Update src/java.base/share/classes/java/lang/Long.java
   
   Co-authored-by: Raffaello Giulietti <raffaello.giulietti at oracle.com>
 - Update src/java.base/share/classes/java/lang/Integer.java
   
   Co-authored-by: Raffaello Giulietti <raffaello.giulietti at oracle.com>

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/22919/files
  - new: https://git.openjdk.org/jdk/pull/22919/files/1fb40bb9..40b9fafa

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=22919&range=13
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=22919&range=12-13

  Stats: 2 lines in 2 files changed: 2 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/22919.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/22919/head:pull/22919

PR: https://git.openjdk.org/jdk/pull/22919