RFR: 8350006: IGV: show memory slices as type information [v4]

[Damon Fenacci]

On Tue, 18 Feb 2025 12:13:45 GMT, Roberto Castañeda Lozano <rcastanedalo at openjdk.org> wrote:

>> This changeset extends the "Show types" filter in IGV to show the memory slice corresponding to each memory node. This information can be useful e.g. in the ongoing investigation of [JDK-8333393](https://bugs.openjdk.org/browse/JDK-8333393). Here is an example of a memory subgraph with the extended "Show types" filter enabled:
>> 
>> ![example](https://github.com/user-attachments/assets/1810a257-c6d6-4b6e-9638-5bbef1c48717)
>> 
>> #### Testing
>> 
>> - tier1 (windows-x64, linux-x64, linux-aarch64, and macosx-x64; release and debug mode).
>> 
>> - Tested IGV manually on a few selected graphs. Tested automatically that displaying thousands of graphs with the "Show types" filter enabled does not trigger any assertion failure (by enabling assertions, instrumenting IGV to display parsed graphs eagerly, and running `java -Xbatch -XX:-TieredCompilation -XX:PrintIdealGraphLevel=3`).
>
> Roberto Castañeda Lozano has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Remove redundant 'alias_field' property

Thanks a lot for the improvement @robcasloz. Like @dlunde I had a few concerns about `dump_spec` being parsed (but testing it a bit didn't seem to reveal any issue). BTW this looks like a good improvement in the direction of making `dump_spec` a bit more understandable (or not needing `dump_spec` in the first place)

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Marked as reviewed by dfenacci (Committer).

PR Review: https://git.openjdk.org/jdk/pull/23621#pullrequestreview-2626098856