RFR: 8307683: Loop Predication wrongly hoists IfNodes without a range check pattern as range check [v2]

[Christian Hagedorn]

On Tue, 30 May 2023 08:44:23 GMT, Severin Gehwolf <sgehwolf at openjdk.org> wrote:

>> Christian Hagedorn has updated the pull request incrementally with two additional commits since the last revision:
>> 
>>  - fix assertion
>>  - new fix with bailout for "if iv <u limit then trap"
>
> This fails the `[compiler/loopopts/TestSkeletonPredicateNegation` test with:
> 
> 
> #
> # A fatal error has been detected by the Java Runtime Environment:
> #
> #  Internal Error (/home/runner/work/jdk/jdk/src/hotspot/share/opto/loopPredicate.cpp:848), pid=32813, tid=32828
> #  assert(!iff->is_RangeCheck()) failed: can only be IfNode because RangeCheckNodes always have trap on false projection
> #
> # JRE version: OpenJDK Runtime Environment (21.0) (fastdebug build 21-internal-chhagedorn-229583b7613867127e42baca158773bcf9c08c73)
> # Java VM: OpenJDK 64-Bit Server VM (fastdebug 21-internal-chhagedorn-229583b7613867127e42baca158773bcf9c08c73, mixed mode, tiered, compressed oops, compressed class ptrs, g1 gc, linux-amd64)
> # Problematic frame:
> # V  [libjvm.so+0x1298438]  IdealLoopTree::is_range_check_if(IfProjNode*, PhaseIdealLoop*, BasicType, Node*, Node*&, Node*&, long&) const+0x278
> #
> # CreateCoredumpOnCrash turned off, no core file dumped
> #
> # An error report file with more information is saved as:
> # /home/runner/work/jdk/jdk/build/run-test-prebuilt/test-support/jtreg_test_hotspot_jtreg_tier1_compiler/scratch/hs_err_pid32813.log
> #
> # Compiler replay data is saved as:
> # /home/runner/work/jdk/jdk/build/run-test-prebuilt/test-support/jtreg_test_hotspot_jtreg_tier1_compiler/scratch/replay_pid32813.log
> #
> # If you would like to submit a bug report, please visit:
> #   https://bugreport.java.com/bugreport/crash.jsp
> #
> result: Error. Agent communication error: java.io.EOFException; check console log for any additional details
> 
> 
> which seems related?

Thanks @jerboaa for reporting that. I've seen that in my testing over the weekend as well. I'm looking into it.

-------------

PR Comment: https://git.openjdk.org/jdk/pull/14156#issuecomment-1568040332