RFR: JDK-8301354: Modernize utilities/breakpoint.hpp [v3]

[Justin King]

On Mon, 30 Jan 2023 15:16:40 GMT, Justin King <jcking at openjdk.org> wrote:

>> Cleanup `utilities/breakpoint.hpp` by utilizing compiler intrinsics when available, or normal signals for AIX/XLC.
>
> Justin King has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Fix reference to unqualified breakpoint
>   
>   Signed-off-by: Justin King <jcking at google.com>

Converting back to draft while I investigate some things.

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PR: https://git.openjdk.org/jdk/pull/12296