[all-commits] [llvm/llvm-project] 829146: [InstCombine] change 'not' match for bitwise select

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  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 829146164f23701f9c5975fadb10ff2d4d100cdc
      https://github.com/llvm/llvm-project/commit/829146164f23701f9c5975fadb10ff2d4d100cdc
  Author: Sanjay Patel <spatel at rotateright.com>
  Date:   2021-11-02 (Tue, 02 Nov 2021)

  Changed paths:
    M llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
    M llvm/test/Transforms/InstCombine/logical-select-inseltpoison.ll
    M llvm/test/Transforms/InstCombine/logical-select.ll

  Log Message:
  -----------
  [InstCombine] change 'not' match for bitwise select

The tests diffs are logically equivalent, and so this is
generally NFC, but this makes the code match the code
comment.

It should also be more efficient. If we choose the 'not'
operand (rather than the 'not' instruction) as the select
condition, then we don't have to invert the select
condition/operands as a subsequent transform.