RFR: 8362893: Improve performance for MemorySegment::getString

[Per Minborg]

On Mon, 28 Jul 2025 05:02:45 GMT, Shaojin Wen <swen at openjdk.org> wrote:

> This optimization is not only needed within the JDK core library, but also by developers of basic class libraries and applications. This should be done by the C2 optimizer.

I suggest that we file a separate PR for C2 to fix all issues of this type and then continue with this PR as proposed.

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PR Comment: https://git.openjdk.org/jdk/pull/26493#issuecomment-3132227714