RFR(S): 8146096 - [TEST BUG] compiler/loopopts/UseCountedLoopSafepoints.java Timeouts
dmitrij.pochepko at oracle.com
Thu Sep 1 14:28:57 UTC 2016
Thank you for attentive review.
> Wow! You wrote "parser" to C2 Ideal graph.
> // now, find SafePoint->CountedLoopEnd edge
> Actually CountedLoopEnd input edge should point to SafePoint. Not
> reverse. You should search from LoopEnd up.
> 115 SafePoint === 112 1 107 1 1 10 110 [[ 116 ]]
> SafePoint !orig=76 !jvms: SimpleTest::testMethod @ bci:21
> 116 CountedLoopEnd === 115 105 [[ 117 118 ]] [lt]
> P=0.500000, C=6633.000000 !orig=97, !jvms: SimpleTest::testMethod
> @ bci:5
> The test is too simple. Without UseCountedLoopSafepoints the loop is
> folded to accum += 100. You need a little more complex.
I've changed increment to combination of different shifts
> Also test should be run only with C2 (Tiered should be off). I don't
> think require vm.opt.TieredStopAtLevel is the same as
Requires expression just help to ensure level 4 is available, because
testMethod specifically compiled on level=4 using WhiteBox
This differs from original test idea to disable tiered compilation and
trigger compilation by running cycle 2 billion times, which made it a
long "stress" test. Now that method compiled via WhiteBox, this test
became much more faster
Please take a look at v03:
> On 8/31/16 12:03 PM, Dmitrij Pochepko wrote:
>> Please take a look at v02.
>> I've rewritten this test. Now it launch vm with
>> -XX:+UseCountedLoopSafepoints (restricting compilation to tested method
>> with single simple counted loop) and checks that output of
>> -XX:+PrintIdeal have edge SafePoint -> CountedLoopEnd
>> Then, launch the same with -XX:-UseCountedLoopSafepoints and checks that
>> there is no such edge.
>> I've tested fix via rbt on all platforms.
>> webrev: http://cr.openjdk.java.net/~dpochepk/8146096/webrev.02/
>> On 29.08.2016 19:28, Vladimir Kozlov wrote:
>>> I am not against marking test as stress but I think the test itself is
>>> not good. It should be rewrote. I added comment to the JBS with
>>> discussion during original 8146096 RFR.
>>> On 8/29/16 7:08 AM, Dmitrij Pochepko wrote:
>>>> please review small fix for 8146096 - [TEST BUG]
>>>> compiler/loopopts/UseCountedLoopSafepoints.java Timeouts
>>>> Test timeouts on slow platforms, so, this fix adds execution control
>>>> with respect to elapsed time. Also, test marked as stress.
>>>> webrev: http://cr.openjdk.java.net/~dpochepk/8146096/webrev.01/
>>>> CR: https://bugs.openjdk.java.net/browse/JDK-8146096
>>>> I've tested this fix on linux-amd64.
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