RFR(M) JDK-8031819: Remove legacy jdk checks and code

[harold seigel]

Hi Coleen,

Thanks for your comments.  I'll make the change that you (and Dave) suggest.

Harold

On 6/10/2014 2:33 PM, Coleen Phillimore wrote:
>
> On 6/10/14, 1:24 PM, harold seigel wrote:
>> Hi David,
>>
>> Thanks for the comments.  Please see my comments inline.
>>
>> Thanks, Harold
>>
>> On 6/10/2014 2:10 AM, David Holmes wrote:
>>> Hi Harold,
>>>
>>> thread.cpp:
>>>
>>> You don't need the comment regarding the change in method to be 
>>> called as again there is no context that tells you there was a 
>>> different method in an earlier release. So this:
>>>
>>> 1742     // JSR-166: change call from ThreadGroup.uncaughtException to
>>> 1743     // java.lang.Thread.dispatchUncaughtException
>>>
>>> can simply be:
>>>
>>> 1742     // Invoke java.lang.Thread.dispatchUncaughtException
>> Done
>>>
>>> You are still checking if dispatchUncaughtException exists but that 
>>> is not necessary so this block can go:
>>>
>>> 1748  CallInfo callinfo;
>>> 1749  KlassHandle 
>>> thread_klass(THREAD,SystemDictionary::Thread_klass());
>>> 1750  LinkResolver::resolve_virtual_call(callinfo, threadObj, 
>>> recvrKlass, thread_klass,
>>> 1751             vmSymbols::dispatchUncaughtException_name(),
>>> 1752             vmSymbols::throwable_void_signature(),
>>> 1753             KlassHandle(), false, false, THREAD);
>>> 1754  CLEAR_PENDING_EXCEPTION;
>>> 1755  methodHandle method = callinfo.selected_method();
>>> 1756  assert(method.not_null(), "Thread.dispatchUncaughtException() 
>>> not found");
>>>
>> I'll remove all of the above except for line 1749. 'thread_klass' is 
>> needed by the subsequent call to call_virtual().
>>> ---
>>>
>>> A few follow ups on your other responses ...
>>>
>>> On 10/06/2014 1:03 AM, harold seigel wrote:
>>>>>> In classLoader.* is it worth renaming/absorbing the is_rt_jar13 and
>>>>>> related "13" items?
>>>> Good suggestion, but I think that this is a lot of change without a
>>>> significant benefit.
>>>
>>> The benefit is code clarity, as noone will understand what the 13 
>>> indicates. It seems to me that the real_jzentry12 and real_jzfile12 
>>> definitions are now unused. So the "13" variants can just drop the 
>>> 13 and is_rt_jar13 becomes is_rt_jar.
>> I'll rename them and post a new webrev.
>>>
>>>>>> systemDictionary.hpp:
>>>>>>
>>>>>> The check_klass_Opt_Only_JDK* functions seem to be unused and only
>>>>>> generated assertion failures when they were used.
>>>>>>
>>>> I was unsure about this change so I did not remove the
>>>> check_klass_Opt_Only_JDK* functions.
>>>
>>> Unsure in what sense - that they are dead code? They seem as dead as 
>>> other things you are deleting :)
>> The check_klass_Opt_Only_JDK* functions cannot be removed because 
>> they are still being used.  The WK_KLASSES_DO and WK_KLASS_DECLARE 
>> macros define functions such as reflect_ConstantPool_klass() and 
>> reflect_MethodAccessorImpl_klass() that call the 
>> check_klass_Opt_Only_JDK* functions:
>>
>>    #define WK_KLASSES_DO(do_klass)  \
>>                          ...
>>       do_klass(reflect_MethodAccessorImpl_klass,
>>    sun_reflect_MethodAccessorImpl, Opt_Only_JDK14NewRef) \
>>       do_klass(reflect_ConstructorAccessorImpl_klass,
>>    sun_reflect_ConstructorAccessorImpl, Opt_Only_JDK14NewRef) \
>>       do_klass(reflect_ConstantPool_klass,
>>    sun_reflect_ConstantPool,                  Opt_Only_JDK15 ) \
>>       do_klass(reflect_UnsafeStaticFieldAccessorImpl_klass,
>>    sun_reflect_UnsafeStaticFieldAccessorImpl, Opt_Only_JDK15 ) \
>
> I think you can change OPT_Only_JDK14NewRef to "Pre" and 
> Opt_Only_JDK15 to "Opt".  More code to remove!
>
> Coleen
>
>> ...
>>
>>       #define WK_KLASS_DECLARE(name, symbol, option) \
>>         static Klass* name() { return
>> check_klass_##option(_well_known_klasses[WK_KLASS_ENUM_NAME(name)]); } \
>>         static Klass** name##_addr() { \
>>           return
>> &SystemDictionary::_well_known_klasses[SystemDictionary::WK_KLASS_ENUM_NAME(name)]; 
>>
>>    \
>>         }
>>       WK_KLASSES_DO(WK_KLASS_DECLARE);
>>
>>   declares:
>>
>>       static Klass* reflect_MethodAccessorImpl_klass { return
>>    check_klass_Opt_Only_JDK14NewRef(...);  }
>>       static Klass* reflect_ConstructorAccessorImpl_klass { return
>>    check_klass_Opt_Only_JDK14NewRef(...);  }
>>       static Klass* reflect_ConstantPool_klass() { return
>>    check_klass_Opt_Only_JDK15(...); }
>>       static Klass* reflect_UnsafeStaticFieldAccessorImpl_klass() {
>>    return check_klass_Opt_Only_JDK15(...);  }
>>
>>>
>>> Thanks,
>>> David
>>
>