RFR: 8358534: Bailout in Conv2B::Ideal when type of cmp input is not supported

[Tobias Hartmann]

On Wed, 4 Jun 2025 06:45:50 GMT, Emanuel Peter <epeter at openjdk.org> wrote:

>> `Conv2BNode::ideal` segfaults in release builds when the type of `in(1)` is not INT or PTR. Creating a small test case to reproduce the issue is being a bit challenging so this PR only address the issue by bailing out of the method if the input type is unsupported. This other ticket https://bugs.openjdk.org/browse/JDK-8357885 will address creating a regression test for the problem.
>> 
>> Tested with JTREG tier1-3 and Renaissance on Linux x64.
>
> src/hotspot/share/opto/convertnode.cpp line 86:
> 
>> 84:         return nullptr;
>> 85:       }
>> 86: 
> 
> @JohnTortugo Would it not have been better to put this check inside the `else` branch?

I agree, the `return nullptr;` should have been added below the assert in the else branch, no check required.

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PR Review Comment: https://git.openjdk.org/jdk/pull/25627#discussion_r2125814466