RFR: 8357816: Add test from JDK-8350576 [v2]

[SendaoYan]

On Thu, 12 Jun 2025 12:25:55 GMT, Benoît Maillard <duke at openjdk.org> wrote:

>> This PR adds a jtreg test for [JDK-8350576](https://bugs.openjdk.org/browse/JDK-8350576). The test consists of a code sample produced by the fuzzer, and it contains a loop that is supposed to get optimized.
>> 
>> Thanks!
>> 
>> ### Testing
>> 
>> - [x] [GitHub Actions](https://github.com/benoitmaillard/jdk/actions?query=branch%3AJDK-8357816)
>> - [ ] tier1-3, plus some internal testing
>> - [x] Ran the test with a debug build prior to the fix (JDK 25 build 16) and made sure it failed as a sanity check
>> 
>> Shout out to @TobiHartmann for helping out with jtreg
>
> Benoît Maillard has updated the pull request incrementally with one additional commit since the last revision:
> 
>   8357816: Add additional run without flags

Hi, `produced by the fuzzer`

How can I use the fuzzer to produce testcases, is there any manual document

test/hotspot/jtreg/compiler/loopopts/LoopReductionHasControlOrBadInput.java line 29:

> 27:  * @summary Optimization bails out and hits an assert:
> 28:  *          assert(false) failed: reduction has ctrl or bad vector_input
> 29:  * @run main/othervm -XX:CompileCommand=compileonly,compiler.loopopts.LoopReductionHasControlOrBadInput::* -Xbatch -XX:-TieredCompilation compiler.loopopts.LoopReductionHasControlOrBadInput

Should we split this long line to two lines.

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PR Comment: https://git.openjdk.org/jdk/pull/25774#issuecomment-2968753712
PR Review Comment: https://git.openjdk.org/jdk/pull/25774#discussion_r2144062909