RFR: JDK-8256725: Metaspace: better blocktree and binlist asserts [v4]

[Richard Reingruber]

On Mon, 23 Nov 2020 14:17:11 GMT, Thomas Stuefe <stuefe at openjdk.org> wrote:

>> Hi,
>> 
>> may I have reviews please for this small change. 
>> 
>> To analyze JDK-8256572, I'd like to see more information in asserts for binlist and blocktree.
>> 
>> This patch:
>> 
>> - beefs up assertion messages when verifying binlist and blocktree
>> - adds a canary to the blocktree node to detect overwriters
>> - improves the blocktree printing
>> - adds a gtest death test to test the overwrite detection.
>> 
>> Thanks!
>
> Thomas Stuefe has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Review feedback Richard+Leo

Looks good.

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Marked as reviewed by rrich (Committer).

PR: https://git.openjdk.java.net/jdk/pull/1339