RFR: 8333658: NMT: Use an allocator with 4-byte pointers to save memory in NativeCallStackStorage [v29]

[Johan Sjölen]

On Mon, 24 Jun 2024 11:48:41 GMT, Thomas Stuefe <stuefe at openjdk.org> wrote:

>> Johan Sjölen has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   Correct placement of include guards
>
> test/hotspot/gtest/nmt/test_homogenousObjectArray.cpp line 152:
> 
>> 150:   A::I i3 = alloc.allocate(0);
>> 151:   EXPECT_EQ(p1, &alloc.at(i3));
>> 152: }
> 
> I think for what little the tests do, testing with different list types is overengineered. You could just scrap both LL and LL2, and just use a HOA directly.

I'd like to push back on that. I believe that while the list tests aren't testing that much they do serve as a form of example of how to use the HOA. It's also useful to have this in the form of a test, as opposed to a comment, as breaking changes to the HOA will break the examples, forcing them to be updated.

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/18979#discussion_r1650909660