RFR: 8370666: VectorAPI: Add clear comments for vector relative code in c2 [v4]

[Emanuel Peter]

On Mon, 19 Jan 2026 03:17:19 GMT, Xiaohong Gong <xgong at openjdk.org> wrote:

>> The VectorMask implementation in Vector API involves complex interactions between types, nodes, and platform-specific
>> features, making the related code in HotSpot difficult to understand and review.
>> 
>> This patch adds comprehensive comments for vector mask related types, nodes, and methods in C2 to improve code clarity and
>> maintainability.
>> 
>> Note: This patch only adds comments; no functional changes are made.
>
> Xiaohong Gong has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Update comments in vectornode.hpp

Marked as reviewed by epeter (Reviewer).

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PR Review: https://git.openjdk.org/jdk/pull/29130#pullrequestreview-3676825832