Request for reviews (M): 6677625: Move platform specific flags from globals.hpp to globals_<arch>.hpp

[Coleen Phillimore]

On 8/21/2012 9:29 PM, David Holmes wrote:
> I'm happy with moving the macros to the top of globals.hpp if that 
> simplifies things.

Yes, I agree.  This change looks great otherwise!

Thanks,
Coleen

>
> Thanks,
> David
>
> On 22/08/2012 11:22 AM, Vladimir Kozlov wrote:
>> David Holmes wrote:
>>> On 22/08/2012 8:47 AM, Vladimir Kozlov wrote:
>>>> David Holmes wrote:
>>>>> I see a lot of changes that aren't obviously pd flags. Is there some
>>>>> other refactoring going on here?
>>>>
>>>> In addition to flags which were used only on one platforms some C2
>>>> specific flags were moved into opto/c2_globals.hpp. And some unused
>>>> flags were removed.
>>>
>>> Ok. But the change in src/share/vm/opto/runtime.cpp seems unrelated to
>>> this work.
>>
>> It is C2 runtime (wrappers for calls into VM runtime).
>> That code was always dead and never used (from some early stage of C2
>> development). It was only a placed where
>> UpdateHotSpotCompilerFileOnError flag was used. So we remove the flag
>> and the code.
>>
>>>
>>> I also think the macros for globals were better placed in globals.hpp
>>> rather than being moved to macros.hpp.
>>
>> The problem was that these macros were defined at the bottom of
>> globals.hpp so they can't be used in platform specific *.hpp which are
>> included at the beginning of globals.hpp. But we can still keep
>> definitions in globals.hpp if we move them to the top instead of
>> #include "utilities/macros.hpp".
>>
>> What do you think?
>>
>>>>> What happens with these changes? Unrecognized VM option? That could
>>>>> break people's scripts.
>>>>
>>>> Yes, they will be unrecognized. There is flag to avoid that and our 
>>>> SQE
>>>> is using it already: -XX:+IgnoreUnrecognizedVMOptions
>>>>
>>>> And we [re]moved flags which should not be used by general public, 
>>>> they
>>>> are our internal flags.
>>>
>>> Well I didn't catalog all those changed but you know that the above is
>>> not true in general. -XX flags are used a lot in places they
>>> "shouldn't". :( Hopefully the PD ones are less likely to be used.
>>
>> I agree with your about -XX general flags. We tried to not touch those.
>>
>>>
>>> Overall I don't understand the form of this change. I would expect all
>>> the platform specific stuff to be in the hpp files included by the
>>> shared cpp file. All these new cpp files seem somewhat redundant to me.
>>
>> You are right.
>>
>> We followed C2_FLAGS definitions and started with X86_FLAGS/SPARC_FLAGS.
>> But then we realized that ARCH_FLAGS could be general since it should be
>> present on all platforms. And next step, as you said, we may be able
>> also move MATERIALIZE code into globals.cpp instead of creating new
>> platform specific .cpp files.
>>
>> I will ask Tao to try it.
>>
>>> And what does an ARCH_PD_ flag mean? I couldn't see any examples of
>>> them. Something different between x86-solaris and x86-linux for 
>>> example?
>>>
>>> And why do we bracket things with identical comments eg:
>>
>> We can remove all that if you agree to move macros definitions to the
>> top of globals.hpp.
>>
>> Thanks,
>> Vladimir
>>
>>>
>>> ! /* all DECLARE_*_FLAG 's are defined in utilities/macros.hpp */
>>> RUNTIME_FLAGS(DECLARE_DEVELOPER_FLAG, DECLARE_PD_DEVELOPER_FLAG, ...
>>>
>>> RUNTIME_OS_FLAGS(DECLARE_DEVELOPER_FLAG, DECLARE_PD_DEVELOPER_FLAG, ...
>>> + /* all DECLARE_*_FLAG 's are defined in utilities/macros.hpp */
>>>
>>>
>>> David
>>> -----
>>>
>>>>
>>>> Thanks,
>>>> Vladimir
>>>>
>>>>>
>>>>> David
>>>>>
>>>>> On 22/08/2012 7:23 AM, Christian Thalinger wrote:
>>>>>> http://cr.openjdk.java.net/~twisti/6677625/
>>>>>>
>>>>>> 6677625: Move platform specific flags from globals.hpp to
>>>>>> globals_<arch>.hpp
>>>>>> Reviewed-by:
>>>>>> Contributed-by: Tao Mao<tao.mao at oracle.com>
>>>>>>
>>>>>> Add new definition RUNTIME_PD_FLAGS and move platform specific flags
>>>>>> from
>>>>>> globals.hpp to globals_<arch>.hpp.
>>>>>>
>>>>>> src/cpu/sparc/vm/globals_sparc.cpp
>>>>>> src/cpu/sparc/vm/globals_sparc.hpp
>>>>>> src/cpu/x86/vm/globals_x86.cpp
>>>>>> src/cpu/x86/vm/globals_x86.hpp
>>>>>> src/cpu/zero/vm/globals_zero.cpp
>>>>>> src/cpu/zero/vm/globals_zero.hpp
>>>>>> src/share/vm/c1/c1_globals.hpp
>>>>>> src/share/vm/opto/c2_globals.cpp
>>>>>> src/share/vm/opto/c2_globals.hpp
>>>>>> src/share/vm/opto/runtime.cpp
>>>>>> src/share/vm/runtime/globals.cpp
>>>>>> src/share/vm/runtime/globals_extension.hpp
>>>>>> src/share/vm/runtime/globals.hpp
>>>>>> src/share/vm/utilities/macros.hpp
>>>>>>