RFR(L): 8077838: Recent developments for ppc.

[Lindenmaier, Goetz]

Thanks, Vladimir!

Best regards,
  Goetz.

-----Original Message-----
From: Vladimir Kozlov [mailto:vladimir.kozlov at oracle.com] 
Sent: Donnerstag, 23. April 2015 16:40
To: Lindenmaier, Goetz; hotspot-dev at openjdk.java.net
Subject: Re: RFR(L): 8077838: Recent developments for ppc.

Thank you for explaining. Last webrev looks fine.

Vladimir

On 4/23/15 7:37 AM, Lindenmaier, Goetz wrote:
> Hi Vladimir,
>
> Yes, the ldarx and stdcx are a pair.  The store is only executed
> if the memory didn't change since the load was done.
> Else a condition is set.
> The condition is used to repeat the sequence.
>
> Best regards,
>    Goetz.
>
> http://www-01.ibm.com/support/knowledgecenter/ssw_aix_53/com.ibm.aix.aixassem/doc/alangref/ldarx.htm%23i806971708sls
> http://www-01.ibm.com/support/knowledgecenter/ssw_aix_53/com.ibm.aix.aixassem/doc/alangref/stdcx_dot.htm%23i807971239sls?lang=en
>
>
> -----Original Message-----
> From: Vladimir Kozlov [mailto:vladimir.kozlov at oracle.com]
> Sent: Donnerstag, 23. April 2015 16:24
> To: Lindenmaier, Goetz; hotspot-dev at openjdk.java.net
> Subject: Re: RFR(L): 8077838: Recent developments for ppc.
>
> On 4/23/15 1:27 AM, Lindenmaier, Goetz wrote:
>> Hi Vladimir,
>>
>> thanks for the review!
>>
>> These methods actually do an atomic update of a memory location, so the name
>> really describes what is happening.
>
> May be I need some PPC education. There are several instructions and branch. Is that some kind of transaction?
>
> Thanks,
> Vladimir
>
>>
>> I'll remove the change to  interpreter_ppc.cpp and runtime_ppc.cpp.
>>
>> Best regards,
>>     Goetz
>>
>> -----Original Message-----
>> From: hotspot-dev [mailto:hotspot-dev-bounces at openjdk.java.net] On Behalf Of Vladimir Kozlov
>> Sent: Donnerstag, 23. April 2015 01:16
>> To: hotspot-dev at openjdk.java.net
>> Subject: Re: RFR(L): 8077838: Recent developments for ppc.
>>
>> Why call methods 'atomic': atomic_inc_ptr() and atomic_ori_int()?
>>
>> Do you really need to change runtime_ppc.cpp only to remove empty line?
>>
>> Looks fine otherwise.
>>
>> Vladimir
>>
>> On 4/22/15 2:34 AM, Lindenmaier, Goetz wrote:
>>> Hi,
>>>
>>> this change contains recent changes in the ppc directory mostly made by SAP.
>>> It's a ppc-only change.
>>> http://cr.openjdk.java.net/~goetz/webrevs/8077838-ppc/webrev.01/
>>>
>>>     - Recognition of Power 8 processors (by Tiago Sturmer Daitx).
>>>     - Support for more new Power 8 instructions.
>>>     - Support for transactional memory. This is implemented but not yet tested
>>>       thoroughly due to limitiations of the OS support. Not enabled.
>>>     - java.lang.math.*Exact intrinsics
>>>     - Some C2 optimizations and fixes:
>>>       * Handling of flag registers. Some instructions would lead to uncompilable
>>>         methods due to not allocatable register patterns.
>>>       * Free some integer registers to use them for allocation. Handle compressed
>>>         oops base as constant.
>>>       * Unscaled class compression.
>>>     - Type profiling fixes.
>>>
>>> Please review this change.
>>>
>>> Best regards,
>>>      Goetz.
>>>
>>>