RFR: 8303279: C2: crash in SubTypeCheckNode::sub() at IGVN split if [v3]

[Roland Westrelin]

On Tue, 27 Jun 2023 20:14:39 GMT, Vladimir Ivanov <vlivanov at openjdk.org> wrote:

>> Roland Westrelin has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   review
>
> src/hotspot/share/opto/ifnode.cpp line 95:
> 
>> 93:   uint i4;
>> 94:   RegionNode* phi_region = phi->region();
>> 95:   for(i4 = 1; i4 < phi->req(); i4++ ) {
> 
> Missing space: `for (i4`.

Done.

> test/hotspot/jtreg/compiler/splitif/TestCrashAtIGVNSplitIfSubType.java line 28:
> 
>> 26:  * @bug 8303279
>> 27:  * @summary C2 Compiler crash (triggered by Kotlin 1.8.10)
>> 28:  * @run main/othervm -XX:-TieredCompilation -XX:-BackgroundCompilation -XX:-UseOnStackReplacement -XX:+PrintCompilation -XX:CompileOnly=TestCrashAtIGVNSplitIfSubType::test -XX:CompileCommand=quiet -XX:+StressIGVN -XX:StressSeed=598200189 TestCrashAtIGVNSplitIfSubType
> 
> Missing flag: `-XX:+StressIGVN` requires `-XX:+UnlockDiagnosticVMOptions`.

Done.

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PR Review Comment: https://git.openjdk.org/jdk/pull/14678#discussion_r1246232169
PR Review Comment: https://git.openjdk.org/jdk/pull/14678#discussion_r1246232289