RFR: 8374889: C2 VectorAPI: must handle impossible combination of signed cast from float [v2]

[John R Rose]

On Wed, 14 Jan 2026 03:35:01 GMT, Quan Anh Mai <qamai at openjdk.org> wrote:

>> src/hotspot/share/opto/vectorIntrinsics.cpp line 2345:
>> 
>>> 2343:       HaltNode* halt = new HaltNode(control(), frameptr(), ss.as_string(C->comp_arena())
>>> 2344:                                                            PRODUCT_ONLY(COMMA /*reachable*/false));
>>> 2345:       _gvn.set_type_bottom(halt);
>> 
>> We create HaltNodes in several places, and all seem to be slightly different.  But it seems that more call sites use transform() instead of set_type_bottom().
>
> It seems there is an opportunity to create a method `GraphKit::halt(const char* reason)` that can be called by these places.

Yes.  I recommend doing this cleanup in this PR.
Unless we think there is a risk that gvn.transform and set_type_bottom will have different effects?
I think they amount to the same thing for a halt node.

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PR Review Comment: https://git.openjdk.org/jdk/pull/29169#discussion_r2688817256