RFR: 8282162: [vector] Optimize vector negation API

[Jie Fu]

On Tue, 15 Mar 2022 02:47:20 GMT, Xiaohong Gong <xgong at openjdk.org> wrote:

> Note that in terms of Java semantics, negation of floating point values needs to be implemented as subtraction from negative zero rather than positive zero:
> 
> double negate(double arg) {return -0.0 - arg; }
> 
> This is to handle signed zeros correctly.

This seems easy to be broken by an opt enhancement.
Just wondering do we have a jtreg test for this point? @jddarcy 
Thanks.

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PR: https://git.openjdk.java.net/jdk/pull/7782