[llvm] [AArch64] Eliminate Common SUBS by Reassociating Non-Constants (PR #123344)

[Marius Kamp via llvm-commits]

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mskamp wrote:

I've added tests for i8, i16, and i64. For i8 and i16, the transformation does not trigger because the operands of the SUBS node are AND nodes whereas the arithmetic operations are performed in 32 bits. Nevertheless, it might be good to have such tests.

https://github.com/llvm/llvm-project/pull/123344