RFR: 8322077: Add Ideal transformation: (~a) | (~b) => ~(a & b)

Thu Dec 14 17:38:04 UTC 2023

Hello,

(~a) | (~b) => ~(a & b) is a widely seen pattern, for example it is implemented for LLVM [here](https://github.com/llvm/llvm-project/blob/397f1ce9efb4eea1ee10fe4833f733b8c7abd878/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp#L1617C28-L1617C28); however it is missing in current implementation of hotspot. This pull request adds this transformation and associated tests.

Thanks.

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Commit messages:
 - include new optimization and tests.

Changes: https://git.openjdk.org/jdk/pull/16334/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=16334&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8322077
  Stats: 158 lines in 4 files changed: 158 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/16334.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/16334/head:pull/16334

PR: https://git.openjdk.org/jdk/pull/16334