[lworld] RFR: 8376135: [lworld] Add JIT support for NULLABLE_NON_ATOMIC_FLAT layout [v4]

[Tobias Hartmann]

On Wed, 28 Jan 2026 13:07:54 GMT, Quan Anh Mai <qamai at openjdk.org> wrote:

>> src/hotspot/share/opto/inlinetypenode.hpp line 71:
>> 
>>> 69: 
>>> 70:   // Initialize the inline type fields with the inputs or outputs of a MultiNode
>>> 71:   void initialize_fields(GraphKit* kit, MultiNode* multi, uint& base_input, bool in, bool no_null_marker, Node* null_check_region, GrowableArray<ciType*>& visited);
>> 
>> Any particular reason that you renamed this? If so, the corresponding argument of  `InlineTypeNode::make_from_multi` should be renamed as well. Could we use something like `has_null_marker` instead to avoid the double negation (`!no_null_marker`)?
>
> The reason I decided to rename it is because it is kind of misleading, `null_free` only means the immediate field is null-free, the object can still be `null`. I am working on a patch to try cleaning up other places, too. `InlineTypeNode::make_from_multi` is correct in its parameter name `null_free`, because it is at the top level. Since all other similar variables in this file is in one direction, I think keeping it consistent would help reduce confusion.

That makes sense, thanks for the details!

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PR Review Comment: https://git.openjdk.org/valhalla/pull/1970#discussion_r2736647307