RFR: 8358735: GenShen: block_start() may be incorrect after class unloading [v12]

[William Kemper]

On Mon, 10 Nov 2025 23:45:39 GMT, Kelvin Nilsen <kdnilsen at openjdk.org> wrote:

>> When scanning a range of dirty cards within the GenShen remembered set, we need to find the object that spans the beginning of the left-most dirty card.  The existing code is not reliable following class unloading.
>> 
>> The new code uses the marking context when it is available to determine the location of live objects that reside below TAMS within each region.  Above TAMS, all objects are presumed live and parsable.
>
> Kelvin Nilsen has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Add two comments

Marked as reviewed by wkemper (Reviewer).

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PR Review: https://git.openjdk.org/jdk/pull/27353#pullrequestreview-3449555306