RFR: 8322077: Add Ideal transformation: (~a) | (~b) => ~(a & b) [v13]

[Tobias Hartmann]

On Wed, 10 Jan 2024 16:57:47 GMT, Zhiqiang Zang <duke at openjdk.org> wrote:

>> 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.
>
> Zhiqiang Zang has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains 34 commits:
> 
>  - Merge branch 'master' of https://github.com/openjdk/jdk into ornode-PNewDeMorganLawOrToAnd
>  - update copyright dates.
>  - Merge branch 'andnode-PNewDeMorganLawAndToOr' into ornode-PNewDeMorganLawOrToAnd
>  - Revert "move the two helper functions to member functions of the node class."
>    
>    This reverts commit 7a962d69ac687c0476e54cd004037f2ebb0800ba.
>  - Revert "update copyright dates."
>    
>    This reverts commit 3665de2f3d38b4fce3ba968ec6247dd2576ecc32.
>  - Revert "move make_not back to AddNode because it cannot compile for architecture arm, s390x, ppc64le."
>    
>    This reverts commit 4ee8b089b6f119b1692dcd2c512d249d92734697.
>  - Revert "adapt changes from the dependent pr."
>    
>    This reverts commit 0c8d10776fe55a28ea9f60160b4f6f57aabad5ab.
>  - Revert "adapt to new changes from the dependant pr."
>    
>    This reverts commit b21e242b306d9cf01e1ba84ebba47ef5b471d98e.
>  - adapt to new changes from the dependant pr.
>  - Merge branch 'andnode-PNewDeMorganLawAndToOr' into ornode-PNewDeMorganLawOrToAnd
>  - ... and 24 more: https://git.openjdk.org/jdk/compare/b86c3b7a...f908668b

All tests passed, this is good to go.

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PR Comment: https://git.openjdk.org/jdk/pull/16334#issuecomment-1889393797