RFR 8209626: [JVMCI] Use implicit exception table for dispatch and printing

[Vladimir Kozlov]

Hi Tom,

Can you add comment to next new code that it is to support old JVMCI? Otherwise it is confusing because in JDK repo we 
will not have the issue:

getDeclaredMethod("implicitExceptionTable");

In jvmci/jvmciRuntime.hpp spacing is not aligned with the rest of arguments.

The rest seems fine.  what testing you did with new code?

Thanks,
Vladimir

On 5/30/19 11:27 AM, Tom Rodriguez wrote:
> I have updated this webrev to include fixes to AOT to properly capture the implicit exception table and record the 
> offset for it in the AOT binary.  It required minor Graal changes which I will push upstream separately.  Please rereview.
> 
> tom
> 
> Tom Rodriguez wrote on 12/12/18 11:22 PM:
>>
>>
>> Vladimir Kozlov wrote on 12/12/18 2:29 PM:
>>> On 12/12/18 1:06 PM, Tom Rodriguez wrote:
>>>> They all look like preexisting failures to me.  The CheckGraalIntrinsics one you mentioned in chat and 
>>>
>>> yes
>>>
>>>> compiler/aot/DeoptimizationTest.java which seems to have been failing at least intermittently for a while.  What do 
>>>> you think?
>>>
>>> SIGFPE is new. And I think your changes in sharedRuntime.cpp may affected execution of AOT methods because they are 
>>> marked as compiled by Graal (compiler_jvmci):
>>>
>>> http://hg.openjdk.java.net/jdk/jdk/file/9e28eff3d40f/src/hotspot/share/aot/aotCompiledMethod.hpp#l131 
>>
>>
>> Yes I think I need to move some code around to properly support AOT. I'll send out an updated webrev soon but I think 
>> we can defer this one until jdk 13.
>>
>> tom
>>
>>>
>>>
>>> Vladimir
>>>
>>>>
>>>> It does make me wonder if AOT needs any extra support to use the implicit exception table.  I would assume we'd be 
>>>> seeing problems if that was the case but don't really know.
>>>>
>>>> tom
>>>>
>>>> Vladimir Kozlov wrote on 12/12/18 11:12 AM:
>>>>> Tom,
>>>>>
>>>>> Some tests failed.
>>>>>
>>>>> Thanks,
>>>>> Vladimir
>>>>>
>>>>> On 12/12/18 10:42 AM, Tom Rodriguez wrote:
>>>>>> http://cr.openjdk.java.net/~never/8209626/webrev
>>>>>> https://bugs.openjdk.java.net/browse/JDK-8209626
>>>>>>
>>>>>> Graal handles implicit exceptions by deoptimizing and that's currently done in a way that's hard to understand 
>>>>>> from the PrintNMethods output. Basically there's just an extra PcDesc at the implicit check location and the 
>>>>>> runtime assumes that a fault with a PcDesc underneath it an implicit check.  This changes JVMCI to use the 
>>>>>> implicit exception table to mark these locations specially which simplifies the dispatching and 
>>>>>> printing.  The new print output looks like this:
>>>>>>
>>>>>>    0x0000000120f053a0: mov    DWORD PTR [rsp-0x14000],eax
>>>>>>    0x0000000120f053a7: sub    rsp,0x18
>>>>>>    0x0000000120f053ab: mov    QWORD PTR [rsp+0x10],rbp ;*aload_0 {reexecute=1 rethrow=0 return_oop=0}
>>>>>>                                                              ; - java.lang.StringLatin1::equals at 0 (line 94)
>>>>>>
>>>>>>    0x0000000120f053b0: mov    eax,DWORD PTR [rsi+0xc]        ; implicit exception: deoptimizes
>>>>>>                                                              ; ImmutableOopMap{rdx=Oop rsi=Oop }
>>>>>> ;*aload_0 {reexecute=1 rethrow=0 return_oop=0}
>>>>>>                                                              ; - java.lang.StringLatin1::equals at 0 (line 94)
>>>>>>
>>>>>>    0x0000000120f053b3: mov    r10d,DWORD PTR [rdx+0xc]       ; implicit exception: deoptimizes
>>>>>>                                                              ; ImmutableOopMap{rdx=Oop rsi=Oop }
>>>>>>
>>>>>> The scope information is still printed in the normal original location. This has been in use with JVMCI 8 for 
>>>>>> several months.
>>>>>>
>>>>>> tom