JDK-8300691 - final variables in for loop headers should accept updates

[Maurizio Cimadamore]

I believe in the new patch Archie has, IF means IF (e.g. the variable we 
are snapshotting is declared in the if statement).

But since Liam was using an earlier iteration, it is possible that the 
results here are a bit skewed.

(Thanks Liam!)

Maurizio

On 17/10/2024 18:14, Brian Goetz wrote:
> I'm guessing, too, that many of those IFs really are hiding METHODDEF 
> or FORLOOP?
>
>
> On 10/17/2024 1:12 PM, Liam Miller-Cushon wrote:
>> I analyzed a sample of code using the changes at 08c8b1f3c64. I can 
>> re-analyze with the latest version, but the initial results were:
>>
>>     120 METHODDEF
>>      74 IF
>>      44 FORLOOP
>>      13 WHILELOOP
>>      10 TRY
>>       5 FOREACHLOOP
>>       2 DOLOOP
>>       1 LAMBDA
>>
>>
>> On Thu, Oct 17, 2024 at 8:08 AM Maurizio Cimadamore 
>> <maurizio.cimadamore at oracle.com> wrote:
>>
>>
>>     On 17/10/2024 16:03, Archie Cobbs wrote:
>>>     On Thu, Oct 17, 2024 at 5:34 AM Maurizio Cimadamore
>>>     <maurizio.cimadamore at oracle.com> wrote:
>>>
>>>         Funny to see the FOREACHLOOP popping out. This code is (at
>>>         least) from 17 years ago (!!) and predates any form of
>>>         effectively final analysis - back then even for-each
>>>         required to hoist the variable in a separate |final| one :-)
>>>
>>>
>>>     I was wondering about that as well. I didn't realize that there
>>>     was a point where foreach() already existed and this effectively
>>>     final tweak was added. I don't see a relevant JEP, did it
>>>     predate the JEP process?
>>     Effectively final support was added as part of Java 8 and Project
>>     Lambda. Java 7 also had some bits of effective finality here and
>>     there, but Java 8 is what sealed the deal. Back then we did not
>>     have the JEP process.
>>>
>>>         I realize, the important info is not where the dummy
>>>         variable is declared. It's the declaration of the variable
>>>         it points to in the initializer that matters!
>>>
>>>
>>>     D'oh, yes of course... easy to fix though.
>>     Thanks
>>>
>>>     Here are the new stats - these look more like what one might expect:
>>>
>>>       87 METHODDEF
>>>       11 FORLOOP
>>>        3 TRY
>>>        3 IF
>>>        3 FOREACHLOOP
>>>        3 DOLOOP
>>>        2 WHILELOOP
>>>        1 CASE
>>>
>>>     Now there are 3 FOREACHLOOP's :)
>>
>>     Yowza! For each gained more than the regular loop :-)
>>
>>     Maurizio
>>
>>>
>>>     -Archie
>>>
>>>     -- 
>>>     Archie L. Cobbs
>>
>
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