RFR: JDK-8321975: Print when add_reserved_region fails even in product mode

[David Holmes]

On Wed, 13 Dec 2023 11:58:40 GMT, Johan Sjölen <jsjolen at openjdk.org> wrote:

> Hi,
> 
> We recently had a user e-mail hotspot-dev about a JVM crash which hit `ShouldNotReachHere` in `add_reserved_region`. As the logging is disabled in product builds the user couldn't supply us with all of the available information, quite unfortunate for us. I propose that we print the region information unconditionally and print the stacks also.

Seems reasonable as long as all the associated `print_on` logic is available in product builds too.

Thanks

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Marked as reviewed by dholmes (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/17086#pullrequestreview-1783200441