RFR: 8369448: C2 SuperWord: refactor VTransform to do move_unordered_reduction_out_of_loop during VTransform::optimize [v2]

[Emanuel Peter]

On Thu, 9 Oct 2025 15:40:41 GMT, Vladimir Kozlov <kvn at openjdk.org> wrote:

>> Can we use  something like `bottom_type()->isa_float() != nullptr || bottom_type()->isa_double() != nullptr` here to check for strict order?
>
> May be use it for assert to make sure we did not miss listing some new vector nodes in this switch in a future.

@vnkozlov I like the idea with an assert on default, so that is what I changed it to now. That way, we won't forget any cases in the future.

`bottom_type()->isa_float() != nullptr || bottom_type()->isa_double() != nullptr`: that does not work (on its own), because float/double min/max do NOT require strict order and can be optimized/reassociated.

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PR Review Comment: https://git.openjdk.org/jdk/pull/27704#discussion_r2418022949