[External] : Re: SuperWord loop optimization lost after method inlining
Vladimir Kozlov
vladimir.kozlov at oracle.com
Sat Feb 20 01:38:39 UTC 2021
BTW, I filed bug to collect information:
https://bugs.openjdk.java.net/browse/JDK-8262067
This is very weird case which I can't reproduce with small test. It reminds me one case (Loop did not transform into
Counted loop) which was fixed in JDK 11.0.3:
https://bugs.openjdk.java.net/browse/JDK-8211451
Thanks,
Vladimir K
On 2/19/21 12:06 PM, Vladimir Kozlov wrote:
> I need an other file C:\Users\NicolasHeutte\AppData\Local\Temp\\hs_c10212_pid15016.log created from second C2 compiler
> thread. It should have data for standalone ArrayFloatToArrayFloatVectorBinding::plus() method compilation. To see what
> is going on I have to compare these data.
>
> Thanks,
> Vladimir K
>
> On 2/19/21 8:54 AM, Nicolas Heutte wrote:
>> Hello Vladimir,
>>
>> I've added the requested log to the shared folder
>> (https://drive.google.com/drive/folders/1UczOggtTYp6TZ0QnBiwMxwdTBl3zuvqF?usp=sharing
>> <https://urldefense.com/v3/__https://drive.google.com/drive/folders/1UczOggtTYp6TZ0QnBiwMxwdTBl3zuvqF?usp=sharing__;!!GqivPVa7Brio!IeK3TGC8Qf5eu0KH3LEkt26TEAWCirLIkTuJ2iAAmTkfBK4_Vnnr6gkOuOydizE_lFhl4g$>).
>> I've also tried disabling the strip mining optimization as you suggested, but there was no significant performance
>> change.
>>
>> Best regards,
>> Nicolas Heutte
>>
>> On Wed, Feb 17, 2021 at 9:05 PM Vladimir Kozlov <vladimir.kozlov at oracle.com <mailto:vladimir.kozlov at oracle.com>> wrote:
>>
>> Unfortunately it is still not the file I am looking for.
>>
>> First, remove -XX:+PrintAssembly flag from command line. I have already files with assembler code.
>>
>> Second, I see link to the file I am looking for:
>> <thread_logfile thread='16812' filename='C:\Users\NicolasHeutte\AppData\Local\Temp\\hs_c16812_pid15016.log'/>
>>
>> If you still have it, please send it. If application stopped before normal exit that file is not merged into
>> hotspot_pid<PID>.log file.
>>
>> If you don't have it - do an other run with -XX:CICompilerCount=1 to use only one C2 compiler thread with Tiered
>> off. It
>> will simplify ordering of log.
>>
>> You can also do an other experiment without collecting log. Run app with next flags to disable loop strip minning
>> optimization: -XX:-UseCountedLoopSafepoints -XX:LoopStripMiningIter=0
>>
>> Thanks,
>> Vladimir K
>>
>> On 2/17/21 2:34 AM, Nicolas Heutte wrote:
>> > Hi Vladimir,
>> >
>> > I have rerun the test with the appropriate options, the obtained logs are in this folder:
>> > https://drive.google.com/drive/folders/1UczOggtTYp6TZ0QnBiwMxwdTBl3zuvqF?usp=sharing
>>
>> <https://urldefense.com/v3/__https://drive.google.com/drive/folders/1UczOggtTYp6TZ0QnBiwMxwdTBl3zuvqF?usp=sharing__;!!GqivPVa7Brio!IeK3TGC8Qf5eu0KH3LEkt26TEAWCirLIkTuJ2iAAmTkfBK4_Vnnr6gkOuOydizE_lFhl4g$>
>>
>>
>> >
>>
>> <https://urldefense.com/v3/__https://drive.google.com/drive/folders/1UczOggtTYp6TZ0QnBiwMxwdTBl3zuvqF?usp=sharing__;!!GqivPVa7Brio!PBl1ZdyC5xtmVS0QG3dxZxEen0D1LP-mBM0KnvmRVbQXpL_VPOQ9OD-pVGBqNvvSUuoKhQ$
>>
>>
>> <https://urldefense.com/v3/__https://drive.google.com/drive/folders/1UczOggtTYp6TZ0QnBiwMxwdTBl3zuvqF?usp=sharing__;!!GqivPVa7Brio!PBl1ZdyC5xtmVS0QG3dxZxEen0D1LP-mBM0KnvmRVbQXpL_VPOQ9OD-pVGBqNvvSUuoKhQ$>>
>>
>> >
>> > Best regards,
>> > Nicolas Heutte
>> >
>> > On Tue, Feb 16, 2021 at 11:35 PM Vladimir Kozlov <vladimir.kozlov at oracle.com <mailto:vladimir.kozlov at oracle.com>
>> <mailto:vladimir.kozlov at oracle.com <mailto:vladimir.kozlov at oracle.com>>> wrote:
>> >
>> > Hi Nicolas,
>> >
>> > The file you shared has only assembler code. Yes, it shows that when
>> ArrayFloatToArrayFloatVectorBinding::plus() is
>> > inlined into AVector::plus() it is not vectorized.
>> >
>> > But I asked for an other file (hotspot_pid<PID>.log) which is generated when you run app with
>> > -XX:+UnlockDiagnosticVMOptions -XX:+LogCompilation flags. It should start with:
>> >
>> > <?xml version='1.0' encoding='UTF-8'?>
>> > <hotspot_log version='160 1' process='2302014' time_ms='1613514688748'>
>> > <vm_version>
>> > <name>
>> > Java HotSpot(TM) 64-Bit Server VM
>> > </name>
>> > <release>
>> > 11.0.9+7-LTS
>> > </release>
>> >
>> > Thanks,
>> > Vladimir K
>> >
>> > On 2/15/21 5:19 AM, Nicolas Heutte wrote:
>> > > Hi Vladimir,
>> > >
>> > > I've tried disabling tiered compilation, as you requested. It seems that the inlining was performed
>> slightly
>> > > differently, but the issue remains. As you can see in this excerpt, the main loop isn't properly
>> vectorized:
>> > >
>> > > 0x00000254b0d4bf54: cmp %r11d,%r8d
>> > > 0x00000254b0d4bf57: jae 0x00000254b0d4c19e
>> > > 0x00000254b0d4bf5d: vmovss 0x10(%rcx,%r8,4),%xmm9 ;*faload {reexecute=0 rethrow=0 return_oop=0}
>> > > ; -
>> > > com.qfs.vector.binding.impl.ArrayFloatToArrayFloatVectorBinding::plus at 54 (line 41)
>> > > ; - com.qfs.vector.impl.AVector::plus at 17 (line 204)
>> > > ; - com.qfs.agg.impl.SumVectorAggregationBinding::plus at 2
>> (line 103)
>> > > ; -
>> > > com.qfs.agg.impl.SumVectorAggregationBinding::safeVectorAggregate at 70 (line 66)
>> > > ; -
>> com.qfs.agg.impl.AVectorAggregationBinding::safeAggregate at 27
>> > (line 118)
>> > >
>> > > 0x00000254b0d4bf64: cmp %ebx,%r8d
>> > > 0x00000254b0d4bf67: jae 0x00000254b0d4c1ec
>> > > 0x00000254b0d4bf6d: vaddss 0x10(%rdi,%r8,4),%xmm9,%xmm9
>> > > 0x00000254b0d4bf74: vmovss %xmm9,0x10(%rcx,%r8,4) ;*fastore {reexecute=0 rethrow=0 return_oop=0}
>> > > ; -
>> > > com.qfs.vector.binding.impl.ArrayFloatToArrayFloatVectorBinding::plus at 61 (line 41)
>> > > ; - com.qfs.vector.impl.AVector::plus at 17 (line 204)
>> > > ; - com.qfs.agg.impl.SumVectorAggregationBinding::plus at 2
>> (line 103)
>> > > ; -
>> > > com.qfs.agg.impl.SumVectorAggregationBinding::safeVectorAggregate at 70 (line 66)
>> > > ; -
>> com.qfs.agg.impl.AVectorAggregationBinding::safeAggregate at 27
>> > (line 118)
>> > >
>> > > 0x00000254b0d4bf7b: inc %r8d ;*iinc {reexecute=0 rethrow=0 return_oop=0}
>> > > ; -
>> > > com.qfs.vector.binding.impl.ArrayFloatToArrayFloatVectorBinding::plus at 62 (line 40)
>> > > ; - com.qfs.vector.impl.AVector::plus at 17 (line 204)
>> > > ; - com.qfs.agg.impl.SumVectorAggregationBinding::plus at 2
>> (line 103)
>> > > ; -
>> > > com.qfs.agg.impl.SumVectorAggregationBinding::safeVectorAggregate at 70 (line 66)
>> > > ; -
>> com.qfs.agg.impl.AVectorAggregationBinding::safeAggregate at 27
>> > (line 118)
>> > >
>> > > 0x00000254b0d4bf7e: cmp %r9d,%r8d
>> > > 0x00000254b0d4bf81: jl 0x00000254b0d4bf54 ;*goto {reexecute=0 rethrow=0 return_oop=0}
>> > > ; -
>> > > com.qfs.vector.binding.impl.ArrayFloatToArrayFloatVectorBinding::plus at 65 (line 40)
>> > > ; - com.qfs.vector.impl.AVector::plus at 17 (line 204)
>> > > ; - com.qfs.agg.impl.SumVectorAggregationBinding::plus at 2
>> (line 103)
>> > > ; -
>> > > com.qfs.agg.impl.SumVectorAggregationBinding::safeVectorAggregate at 70 (line 66)
>> > > ; -
>> com.qfs.agg.impl.AVectorAggregationBinding::safeAggregate at 27
>> > (line 118)
>> > >
>> > >
>> > >
>> > > Here is the link to the full log, should you want to take a look at it:
>> > > https://drive.google.com/file/d/1KQU7wI8NjeElFv6RrQmUsUPRMnAefzhb/view?usp=sharing
>>
>> <https://urldefense.com/v3/__https://drive.google.com/file/d/1KQU7wI8NjeElFv6RrQmUsUPRMnAefzhb/view?usp=sharing__;!!GqivPVa7Brio!IeK3TGC8Qf5eu0KH3LEkt26TEAWCirLIkTuJ2iAAmTkfBK4_Vnnr6gkOuOydizGvKpVqaQ$>
>>
>> >
>> <https://urldefense.com/v3/__https://drive.google.com/file/d/1KQU7wI8NjeElFv6RrQmUsUPRMnAefzhb/view?usp=sharing__;!!GqivPVa7Brio!PBl1ZdyC5xtmVS0QG3dxZxEen0D1LP-mBM0KnvmRVbQXpL_VPOQ9OD-pVGBqNvuMpg6inQ$
>> <https://urldefense.com/v3/__https://drive.google.com/file/d/1KQU7wI8NjeElFv6RrQmUsUPRMnAefzhb/view?usp=sharing__;!!GqivPVa7Brio!PBl1ZdyC5xtmVS0QG3dxZxEen0D1LP-mBM0KnvmRVbQXpL_VPOQ9OD-pVGBqNvuMpg6inQ$>>
>>
>> >
>> > >
>> >
>> <https://urldefense.com/v3/__https://drive.google.com/file/d/1KQU7wI8NjeElFv6RrQmUsUPRMnAefzhb/view?usp=sharing__;!!GqivPVa7Brio!PBuP6MfDNWUOTe23SSXA0V5wn_VHjv2sjI8POWRwp6mr0wVdIzFhNoVZANb4FqCYKwzapw$
>> <https://urldefense.com/v3/__https://drive.google.com/file/d/1KQU7wI8NjeElFv6RrQmUsUPRMnAefzhb/view?usp=sharing__;!!GqivPVa7Brio!PBuP6MfDNWUOTe23SSXA0V5wn_VHjv2sjI8POWRwp6mr0wVdIzFhNoVZANb4FqCYKwzapw$>
>>
>> >
>> <https://urldefense.com/v3/__https://drive.google.com/file/d/1KQU7wI8NjeElFv6RrQmUsUPRMnAefzhb/view?usp=sharing__;!!GqivPVa7Brio!PBuP6MfDNWUOTe23SSXA0V5wn_VHjv2sjI8POWRwp6mr0wVdIzFhNoVZANb4FqCYKwzapw$
>> <https://urldefense.com/v3/__https://drive.google.com/file/d/1KQU7wI8NjeElFv6RrQmUsUPRMnAefzhb/view?usp=sharing__;!!GqivPVa7Brio!PBuP6MfDNWUOTe23SSXA0V5wn_VHjv2sjI8POWRwp6mr0wVdIzFhNoVZANb4FqCYKwzapw$>>>
>>
>> > >
>> > > Best regards,
>> > > Nicolas Heutte
>> > >
>> > > On Thu, Feb 11, 2021 at 7:05 PM Vladimir Kozlov <vladimir.kozlov at oracle.com
>> <mailto:vladimir.kozlov at oracle.com> <mailto:vladimir.kozlov at oracle.com <mailto:vladimir.kozlov at oracle.com>>
>> > <mailto:vladimir.kozlov at oracle.com <mailto:vladimir.kozlov at oracle.com> <mailto:vladimir.kozlov at oracle.com
>> <mailto:vladimir.kozlov at oracle.com>>>> wrote:
>> > >
>> > > Changing wide mailing list to JIT compiler only.
>> > >
>> > > This deoptimization is normal in Tiered Compilation - it switched from profiling code (level='3')
>> generated by C1
>> > > compiler to new code generated by C2 (level='4') which does loop optimizations.
>> > >
>> > > Thank you for posting inlining information:
>> > >
>> > > @ 17 com.qfs.vector.binding.impl.ArrayFloatToArrayFloatVectorBinding::plus (69 bytes) inline
>> (hot)
>> > > \-> TypeProfile (14054/14054 counts) =
>> com/qfs/vector/binding/impl/ArrayFloatToArrayFloatVectorBinding
>> > >
>> > > I thought before that may be call site is not hot but it is not the case.
>> > >
>> > > You can do an other experiment to collect log with disabled Tiered Compilation (only C2 is used):
>> > -XX:-TieredCompilation
>> > > Also print assembler code (as you did before) for final compilation to see if loop is still not
>> vectorized.
>> > >
>> > > Is it possible to post log file (on GitHub?) for me to look?
>> > >
>> > > Thanks,
>> > > Vladimir K
>> > >
>> > > On 2/11/21 6:28 AM, Nicolas Heutte wrote:
>> > > > Hi Vladimir,
>> > > >
>> > > > Thank you for your help.
>> > > >
>> > > > I'm currently running Java 11.0.9, and I did not use any VM flag of note.
>> > > >
>> > > > I checked the content of the compilation log, and it seems that
>> > ArrayFloatToArrayFloatVectorBinding::plus() was
>> > > > deoptimized in order to allow AVector::plus() to be compiled:
>> > > >
>> > > > <writer thread='11576'/>
>> > > > <task_queued compile_id='17280' method='com.qfs.vector.impl.AVector plus
>> (Lcom/qfs/vector/IVector;)V'
>> > bytes='23'
>> > > > count='916' iicount='916' level='3' stamp='7394.056' comment='tiered' hot_count='896'/>
>> > > > <writer thread='15784'/>
>> > > > <deoptimized thread='15784' reason='constraint' pc='0x00000296d0785b94' compile_id='17257'
>> compiler='c1'
>> > level='3'>
>> > > > <jvms bci='65' method='com.qfs.vector.binding.impl.ArrayFloatToArrayFloatVectorBinding plus
>> > > > (Lcom/qfs/vector/IVector;Lcom/qfs/vector/IVector;)V' bytes='69' count='909' backedge_count='155602'
>> > iicount='910'/>
>> > > > </deoptimized>
>> > > >
>> > > > The last compilation entry for AVector::plus() is:
>> > > >
>> > > > <writer thread='16380'/>
>> > > > <nmethod compile_id='17317' compiler='c2' level='4' entry='0x00000296d6af32c0' size='1960'
>> > > address='0x00000296d6af3110'
>> > > > relocation_offset='376' insts_offset='432' stub_offset='1040' scopes_data_offset='1152'
>> > scopes_pcs_offset='1592'
>> > > > dependencies_offset='1880' nul_chk_table_offset='1896' oops_offset='1064' metadata_offset='1072'
>> > > > method='com.qfs.vector.impl.AVector plus (Lcom/qfs/vector/IVector;)V' bytes='23' count='172425'
>> > iicount='172425'
>> > > > stamp='7394.199'/>
>> > > > <make_not_entrant thread='16380' compile_id='17280' compiler='c1' level='2' stamp='7394.199'/>
>> > > > @ 1 com.qfs.vector.array.impl.ArrayFloatVector::getBindingId (4
>> bytes)
>> > inline
>> > > (hot)
>> > > > \-> TypeProfile (14552/14552 counts) =
>> > com/qfs/vector/array/impl/ArrayFloatVector
>> > > > @ 7 com.qfs.vector.array.impl.ArrayFloatVector::getBindingId (4
>> bytes)
>> > inline
>> > > (hot)
>> > > > \-> TypeProfile (14150/14150 counts) =
>> > com/qfs/vector/array/impl/ArrayFloatVector
>> > > > @ 10 com.qfs.vector.binding.impl.VectorBindings::getBinding (9
>> bytes)
>> > inline (hot)
>> > > > @ 5
>> > > com.qfs.vector.binding.impl.VectorBindings$VectorBindingsProvider::getBinding (22
>> > > > bytes) inline (hot)
>> > > > @ 3
>> > > com.qfs.vector.binding.impl.VectorBindings$VectorBindingsProvider::hasBinding
>> > > > (34 bytes) inline (hot)
>> > > > @ 17
>> > com.qfs.vector.binding.impl.ArrayFloatToArrayFloatVectorBinding::plus (69
>> > > bytes)
>> > > > inline (hot)
>> > > > \-> TypeProfile (14054/14054 counts) =
>> > > > com/qfs/vector/binding/impl/ArrayFloatToArrayFloatVectorBinding
>> > > > @ 12 com.qfs.vector.array.impl.ArrayFloatVector::size (6 bytes)
>> > inline (hot)
>> > > > @ 22 com.qfs.vector.impl.AVector::checkIndex (37 bytes) inline
>> (hot)
>> > > > @ 6 com.qfs.vector.array.impl.ArrayFloatVector::size (6 bytes)
>> > inline (hot)
>> > > > @ 27 com.qfs.vector.array.impl.ArrayFloatVector::getUnderlying
>> (5 bytes)
>> > > accessor
>> > > > @ 34 com.qfs.vector.array.impl.ArrayFloatVector::getUnderlying
>> (5 bytes)
>> > > accessor
>> > > > <writer thread='15896'/>
>> > > >
>> > > > Unfortunately, I do not have access to a debug VM build, so I cannot run the second test you
>> recommend.
>> > > >
>> > > > Best regards,
>> > > > Nicolas Heutte
>> > > >
>> > > > On Wed, Feb 10, 2021 at 7:36 PM Vladimir Kozlov <vladimir.kozlov at oracle.com
>> <mailto:vladimir.kozlov at oracle.com>
>> > <mailto:vladimir.kozlov at oracle.com <mailto:vladimir.kozlov at oracle.com>> <mailto:vladimir.kozlov at oracle.com
>> <mailto:vladimir.kozlov at oracle.com> <mailto:vladimir.kozlov at oracle.com <mailto:vladimir.kozlov at oracle.com>>>
>> > > <mailto:vladimir.kozlov at oracle.com <mailto:vladimir.kozlov at oracle.com>
>> <mailto:vladimir.kozlov at oracle.com <mailto:vladimir.kozlov at oracle.com>> <mailto:vladimir.kozlov at oracle.com
>> <mailto:vladimir.kozlov at oracle.com>
>> > <mailto:vladimir.kozlov at oracle.com <mailto:vladimir.kozlov at oracle.com>>>>> wrote:
>> > > >
>> > > > Hi, Nicolas
>> > > >
>> > > > Looks like, when inlined, the loop from ArrayFloatToArrayFloatVectorBinding::plus() was not
>> optimized
>> > at all:
>> > > it is not
>> > > > unrolled and has range checks. Such loops are not vectorized (you need unrolling and no checks).
>> > > >
>> > > > What Java version you are running? What HotSpot VM flags you are using when running application?
>> > > >
>> > > > Run application with -XX:+LogCompilation and look on compilation data in hotspot_pid<PID>.log
>> file for
>> > caller
>> > > > AVector::plus().
>> > > >
>> > > > VM also has several flags to trace loop optimizations but they are only available in debug VM
>> build.
>> > If you
>> > > have access
>> > > > to such build run with -XX:+PrintCompilation -XX:+TraceLoopOpts flags.
>> > > >
>> > > > Thanks,
>> > > > Vladimir K
>> > > >
>> > > > On 2/10/21 9:24 AM, Nicolas Heutte wrote:
>> > > > > Hi all,
>> > > > >
>> > > > > I am encountering a performance issue caused by the interaction between
>> > > > > method inlining and automatic vectorization.
>> > > > >
>> > > > > Our application aggregates arrays intensively using a method named
>> > > > > ArrayFloatToArrayFloatVectorBinding.plus() with the following code:
>> > > > >
>> > > > > for (int i = 0; i < srcLen; ++i) {
>> > > > >
>> > > > > dstArray[i] += srcArray[i];
>> > > > >
>> > > > > }
>> > > > >
>> > > > > When we microbenchmark this method we observe fast performance close to the
>> > > > > practical memory bandwidth and when we print the assembly code we observe
>> > > > > loop unrolling and automatic vectorization with SIMD instructions.
>> > > > >
>> > > > > 0x000001ef4600abf0: vmovdqu 0x10(%r14,%r13,4),%ymm0
>> > > > >
>> > > > > 0x000001ef4600abf7: vaddps 0x10(%rcx,%r13,4),%ymm0,%ymm0
>> > > > >
>> > > > > 0x000001ef4600abfe: vmovdqu %ymm0,0x10(%r14,%r13,4)
>> > > > >
>> > > > > 0x000001ef4600ac05: movslq %r13d,%r11
>> > > > >
>> > > > > 0x000001ef4600ac08: vmovdqu 0x30(%r14,%r11,4),%ymm0
>> > > > >
>> > > > > 0x000001ef4600ac0f: vaddps 0x30(%rcx,%r11,4),%ymm0,%ymm0
>> > > > >
>> > > > > 0x000001ef4600ac16: vmovdqu %ymm0,0x30(%r14,%r11,4)
>> > > > >
>> > > > > 0x000001ef4600ac1d: vmovdqu 0x50(%r14,%r11,4),%ymm0
>> > > > >
>> > > > > 0x000001ef4600ac24: vaddps 0x50(%rcx,%r11,4),%ymm0,%ymm0
>> > > > >
>> > > > > 0x000001ef4600ac2b: vmovdqu %ymm0,0x50(%r14,%r11,4)
>> > > > >
>> > > > > 0x000001ef4600ac32: vmovdqu 0x70(%r14,%r11,4),%ymm0
>> > > > >
>> > > > > 0x000001ef4600ac39: vaddps 0x70(%rcx,%r11,4),%ymm0,%ymm0
>> > > > >
>> > > > > 0x000001ef4600ac40: vmovdqu %ymm0,0x70(%r14,%r11,4)
>> > > > >
>> > > > > 0x000001ef4600ac47: vmovdqu 0x90(%r14,%r11,4),%ymm0
>> > > > >
>> > > > > 0x000001ef4600ac51: vaddps 0x90(%rcx,%r11,4),%ymm0,%ymm0
>> > > > >
>> > > > > 0x000001ef4600ac5b: vmovdqu %ymm0,0x90(%r14,%r11,4)
>> > > > >
>> > > > > 0x000001ef4600ac65: vmovdqu 0xb0(%r14,%r11,4),%ymm0
>> > > > >
>> > > > > 0x000001ef4600ac6f: vaddps 0xb0(%rcx,%r11,4),%ymm0,%ymm0
>> > > > >
>> > > > > 0x000001ef4600ac79: vmovdqu %ymm0,0xb0(%r14,%r11,4)
>> > > > >
>> > > > > 0x000001ef4600ac83: vmovdqu 0xd0(%r14,%r11,4),%ymm0
>> > > > >
>> > > > > 0x000001ef4600ac8d: vaddps 0xd0(%rcx,%r11,4),%ymm0,%ymm0
>> > > > >
>> > > > > 0x000001ef4600ac97: vmovdqu %ymm0,0xd0(%r14,%r11,4)
>> > > > >
>> > > > > 0x000001ef4600aca1: vmovdqu 0xf0(%r14,%r11,4),%ymm0
>> > > > >
>> > > > > 0x000001ef4600acab: vaddps 0xf0(%rcx,%r11,4),%ymm0,%ymm0
>> > > > >
>> > > > > 0x000001ef4600acb5: vmovdqu %ymm0,0xf0(%r14,%r11,4) ;*fastore
>> > > > > {reexecute=0 rethrow=0 return_oop=0}
>> > > > >
>> > > > > ; -
>> > > > > com.qfs.vector.binding.impl.ArrayFloatToArrayFloatVectorBinding::plus at 61
>> > > > > (line 41)
>> > > > >
>> > > > > 0x000001ef4600acbf: add $0x40,%r13d ;*iinc {reexecute=0
>> > > > > rethrow=0 return_oop=0}
>> > > > >
>> > > > > ; -
>> > > > > com.qfs.vector.binding.impl.ArrayFloatToArrayFloatVectorBinding::plus at 62
>> > > > > (line 40)
>> > > > >
>> > > > > 0x000001ef4600acc3: cmp %eax,%r13d
>> > > > >
>> > > > > 0x000001ef4600acc6: jl 0x000001ef4600abf0 ;*goto {reexecute=0
>> > > > > rethrow=0 return_oop=0}
>> > > > >
>> > > > > ; -
>> > > > > com.qfs.vector.binding.impl.ArrayFloatToArrayFloatVectorBinding::plus at 65
>> > > > > (line 40)
>> > > > >
>> > > > >
>> > > > >
>> > > > > In the real application, this method is actually inlined in a higher level
>> > > > > method named AVector.plus(). Unfortunately, the inlined version of the
>> > > > > aggregation code is not vectorized anymore:
>> > > > >
>> > > > >
>> > > > >
>> > > > > 0x000001ef460180a0: cmp %ebx,%r11d
>> > > > >
>> > > > > 0x000001ef460180a3: jae 0x000001ef460180e6
>> > > > >
>> > > > > 0x000001ef460180a5: vmovss 0x10(%r8,%r11,4),%xmm1 ;*faload {reexecute=0
>> > > > > rethrow=0 return_oop=0}
>> > > > >
>> > > > > ; -
>> > > > > com.qfs.vector.binding.impl.ArrayFloatToArrayFloatVectorBinding::plus at 54
>> > > > > (line 41)
>> > > > >
>> > > > > ; -
>> > > > > com.qfs.vector.impl.AVector::plus at 17 (line 204)
>> > > > >
>> > > > > 0x000001ef460180ac: cmp %ecx,%r11d
>> > > > >
>> > > > > 0x000001ef460180af: jae 0x000001ef46018104
>> > > > >
>> > > > > 0x000001ef460180b1: vaddss 0x10(%r9,%r11,4),%xmm1,%xmm1
>> > > > >
>> > > > > 0x000001ef460180b8: vmovss %xmm1,0x10(%r8,%r11,4) ;*fastore {reexecute=0
>> > > > > rethrow=0 return_oop=0}
>> > > > >
>> > > > > ; -
>> > > > > com.qfs.vector.binding.impl.ArrayFloatToArrayFloatVectorBinding::plus at 61
>> > > > > (line 41)
>> > > > >
>> > > > > ; -
>> > > > > com.qfs.vector.impl.AVector::plus at 17 (line 204)
>> > > > >
>> > > > > 0x000001ef460180bf: inc %r11d ;*iinc {reexecute=0
>> > > > > rethrow=0 return_oop=0}
>> > > > >
>> > > > > ; -
>> > > > > com.qfs.vector.binding.impl.ArrayFloatToArrayFloatVectorBinding::plus at 62
>> > > > > (line 40)
>> > > > >
>> > > > > ; -
>> > > > > com.qfs.vector.impl.AVector::plus at 17 (line 204)
>> > > > >
>> > > > > 0x000001ef460180c2: cmp %r10d,%r11d
>> > > > >
>> > > > > 0x000001ef460180c5: jl 0x000001ef460180a0 ;*goto {reexecute=0
>> > > > > rethrow=0 return_oop=0}
>> > > > >
>> > > > > ; -
>> > > > > com.qfs.vector.binding.impl.ArrayFloatToArrayFloatVectorBinding::plus at 65
>> > > > > (line 40)
>> > > > >
>> > > > > ; -
>> > > > > com.qfs.vector.impl.AVector::plus at 17 (line 204)
>> > > > >
>> > > > >
>> > > > >
>> > > > > This causes a significant performance drop, compared to a run where we
>> > > > > explicitly disable the inlining and observe automatically vectorized code
>> > > > > again (
>> > > > >
>> -XX:CompileCommand=dontinline,com/qfs/vector/binding/impl/ArrayFloatToArrayFloatVectorBinding.plus
>> > > > > ).
>> > > > >
>> > > > >
>> > > > > How do you guys explain that behavior of the JIT compiler? Is this a known
>> > > > > and tracked issue, could it be fixed in the JVM? Can we do something in the
>> > > > > java code to prevent this from happening?
>> > > > >
>> > > > >
>> > > > > Best regards,
>> > > > >
>> > > > > Nicolas Heutte
>> > > > >
>> > > >
>> > >
>> >
>>
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