RFR: 8234906: [TESTBUG] TestDivZeroCheckControl fails for client VMs due to Unrecognized VM option LoopUnrollLimit

[Vladimir Kozlov]

You don't need to duplicate @bug (it was C2 bug anyway). And don't need to check  & !vm.graal.enabled for C2 case (see 
explanation below)

 > Could you elaborate how the two flags are related? I though, if graal is
 > used as a JIT, both `vm.graal.enabled` and `vm.compiler2.enabled` are set
 > to true. Is that correct? I don't have a setup with graal, so I can not
 > test this.

When we enable Graal JIT it is used instead of C2. They are mutually exclusive.
Compiler.isC2Enabled() (which sets vm.compiler2.enabled [1]) returns false when isGraalEnabled() returns true [2].

Regards,
Vladimir

[1] http://hg.openjdk.java.net/jdk/jdk/file/138b0f3fe18c/test/jtreg-ext/requires/VMProps.java#l117
[2] http://hg.openjdk.java.net/jdk/jdk/file/138b0f3fe18c/test/lib/sun/hotspot/code/Compiler.java#l80


On 12/3/19 4:22 AM, christoph.goettschkes at microdoc.com wrote:
> Hi Vladimir,
> 
> could you have a look at my updated webrev regarding this failing test?
> https://cr.openjdk.java.net/~cgo/8234906/webrev.01/
> 
> See my inline comments in the mail below.
> 
> Thanks,
> Christpoh
> 
> "hotspot-compiler-dev" <hotspot-compiler-dev-bounces at openjdk.java.net>
> wrote on 2019-11-28 13:44:05:
> 
>> From: christoph.goettschkes at microdoc.com
>> To: Vladimir Kozlov <vladimir.kozlov at oracle.com>
>> Cc: hotspot-compiler-dev at openjdk.java.net
>> Date: 2019-11-28 13:46
>> Subject: Re: RFR: 8234906: [TESTBUG] TestDivZeroCheckControl fails for
>> client VMs due to Unrecognized VM option LoopUnrollLimit
>> Sent by: "hotspot-compiler-dev"
> <hotspot-compiler-dev-bounces at openjdk.java.net>
>>
>> Hi Vladimir,
>>
>> Vladimir Kozlov <vladimir.kozlov at oracle.com> wrote on 2019-11-27
> 20:54:02:
>>
>>> From: Vladimir Kozlov <vladimir.kozlov at oracle.com>
>>> To: christoph.goettschkes at microdoc.com,
>> hotspot-compiler-dev at openjdk.java.net
>>> Date: 2019-11-27 20:54
>>> Subject: Re: RFR: 8234906: [TESTBUG] TestDivZeroCheckControl fails for
> 
>>> client VMs due to Unrecognized VM option LoopUnrollLimit
>>>
>>> Hi Christoph
>>>
>>> I was about suggest IgnoreUnrecognizedVMOptions flag but remembered
>>> discussion about 8231954 fix.
>>
>> Yes, I try to avoid "IgnoreUnrecognizedVMOptions" because of our
> previous
>> discussion. I also think that it doesn't make sense to execute tests in
> VM
>> configurations for which they are not written for. Most of the compiler
>> tests simply have "IgnoreUnrecognizedVMOptions" and probably waste a
> good
>> amount of time in certain VM configurations.
>>
>>> But I think the test should be run with Graal - it does have OSR
>>> compilation and we need to test it.
>>
>> Sure. I disabled it, because I thought that the flag "LoopUnrollLimit"
> is
>> required to trigger the faulty behavior, but I don't know much about
>> optimization in the graal JIT.
>>
>>>
>>> We can do it by splitting test runs (duplicate @test block with
>>> different run flags) to have 2 tests with different
>>> flags and conditions. See [1].
>>>
>>> For existing @run block we use `@requires vm.compiler2.enabled` and
> for
>>> new without LoopUnrollLimit - `vm.graal.enabled`.
>>
>> I did the following:
>>
>> https://cr.openjdk.java.net/~cgo/8234906/webrev.01/
>>
>> Could you elaborate how the two flags are related? I though, if graal is
> 
>> used as a JIT, both `vm.graal.enabled` and `vm.compiler2.enabled` are
> set
>> to true. Is that correct? I don't have a setup with graal, so I can not
>> test this.
>>
>> Thanks,
>> Christoph
>>
>