RFR: 8369167: C2: refactor LShiftINode/LShiftLNode Value/Identity/Ideal [v2]

[Roland Westrelin]

> This change refactor code that's similar for LShiftINode and
> LShiftLNode into shared methods. I also added extra test cases to
> cover all transformations.

Roland Westrelin has updated the pull request incrementally with one additional commit since the last revision:

  sort headers

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Changes:
  - all: https://git.openjdk.org/jdk/pull/27725/files
  - new: https://git.openjdk.org/jdk/pull/27725/files/ba8dc6df..05ff54dc

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=27725&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=27725&range=00-01

  Stats: 2 lines in 1 file changed: 1 ins; 1 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/27725.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/27725/head:pull/27725

PR: https://git.openjdk.org/jdk/pull/27725