C2 crash in PhaseIdealLoop::build_loop_late_post_work

[Christian Hagedorn]

Hi Martin

Thanks for the pointer! I will have a look at that.

Best regards,
Christian

On 27.10.20 16:28, Doerr, Martin wrote:
> Hi Christian,
> 
> thanks for your reply.
> 
> Interesting. Another issue related to JDK-8249749 was recently fixed:
> 8251994: VM crashed running TestComplexAddrExpr.java test with -XX:UseAVX=X
> https://bugs.openjdk.java.net/browse/JDK-8251994
> Maybe it helps for this, too.
> 
> I don’t have a fast reproducer atm.
> 
> Best regards,
> Martin
> 
> 
>> -----Original Message-----
>> From: Christian Hagedorn <christian.hagedorn at oracle.com>
>> Sent: Dienstag, 27. Oktober 2020 13:03
>> To: Doerr, Martin <martin.doerr at sap.com>; 'hotspot-compiler-
>> dev at openjdk.java.net' <hotspot-compiler-dev at openjdk.java.net>
>> Subject: Re: C2 crash in PhaseIdealLoop::build_loop_late_post_work
>>
>> Hi Martin
>>
>> Yes, this is a known problem (see JDK-8251925). We also see it failing
>> with only this benchmark, often in log-regression. I played around with
>> different settings by just running log-regression, for example, which
>> did not seem to trigger it, though. Do you have a fast reproducer?
>>
>> It started to fail after JDK-8249749 which, however, just seem to have
>> revealed the problem.
>>
>> Best regards,
>> Christian
>>
>> On 27.10.20 12:07, Doerr, Martin wrote:
>>> Hi,
>>>
>>> we observe C2 crashes on all x86_64 platforms when running Renaissance
>> Benchmark "log-regression" since 2020-08-10.
>>> (hg was at "8250848: [aarch64] nativeGotJump_at() missing call to verify()."
>> when we've seen it first.)
>>>
>>>
>>> #  EXCEPTION_ACCESS_VIOLATION (0xc0000005) at
>> pc=0x00007ffd594e9322, pid=1439804, tid=1516348
>>>
>>> #
>>>
>>> # JRE version: OpenJDK Runtime Environment (16.0.0.1) (build 16.0.0.1-
>> internal+0-adhoc.openjdk.jdk-dev)
>>>
>>> # Java VM: OpenJDK 64-Bit Server VM (16.0.0.1-internal+0-
>> adhoc.openjdk.jdk-dev, mixed mode, sharing, tiered, compressed oops, g1
>> gc, windows-amd64)
>>>
>>> # Problematic frame:
>>>
>>> # V  [jvm.dll+0x559322]
>> PhaseIdealLoop::build_loop_late_post_work+0x212
>>>
>>>
>>>
>>> Host: Intel(R) Xeon(R) CPU E7-8880 v4 @ 2.20GHz, 8 cores, 15G,  Windows
>> Server 2016 , 64 bit Build 14393 (10.0.14393.3630)
>>>
>>> Time: Sat Oct 24 19:40:57 2020 W. Europe Daylight Time elapsed time:
>> 16.016253 seconds (0d 0h 0m 16s)
>>>
>>>
>>> V  [jvm.dll+0x559322]  PhaseIdealLoop::build_loop_late_post_work+0x212
>> (loopnode.cpp:5312)
>>>
>>> V  [jvm.dll+0x5590b4]  PhaseIdealLoop::build_loop_late+0x214
>> (loopnode.cpp:5159)
>>>
>>> V  [jvm.dll+0x558418]  PhaseIdealLoop::build_and_optimize+0x7b8
>> (loopnode.cpp:3874)
>>>
>>> V  [jvm.dll+0x21410a]  Compile::optimize_loops+0x15a  (compile.cpp:1960)
>>>
>>> V  [jvm.dll+0x20d900]  Compile::Optimize+0xf90  (compile.cpp:2184)
>>>
>>> V  [jvm.dll+0x20b105]  Compile::Compile+0xba5  (compile.cpp:735)
>>>
>>> V  [jvm.dll+0x19de6b]  C2Compiler::compile_method+0xab
>> (c2compiler.cpp:104)
>>>
>>> Is this a known problem?
>>>
>>> Best regards,
>>> Martin
>>>