RFR: 8142984: Zero: fast accessors should handle both getters and setters [v2]

[Andrew John Hughes]

On Wed, 28 Oct 2020 09:56:31 GMT, Aleksey Shipilev <shade at openjdk.org> wrote:

>> It started as removing the TODO item in `abstractInterpreter.cpp`. Zero is the only implementation that treats `accessor` to mean `getter`, which makes the awkward choice in the entry selection. After going back and forth (including trying to remove the fast accessor methods altogether in [JDK-8255066](https://bugs.openjdk.java.net/browse/JDK-8255066)), I settled on implementing the fast Zero `setter`-s too, plus renaming and whipping the existing `getter` code in shape. The end result seems to be more straight-forward than it was before.
>> 
>> On the plus side, it improves `make bootcycle-images` in release mode from ~47m40s to ~46m50s, because we are saving time doing the `normal_entry` for setters.
>> 
>> The "normal", non-Zero template interpreter is not affected, because it does not have any specializations for `accessor`, `getter` or `setter`, and instead just doing the normal entry.
>> 
>> Testing:
>>   - [x] Linux x86_64 {fastdebug, release} Zero `make bootcycle-images`
>>   - [x] Linux aarch64 {fastdebug, release} Zero `make bootcycle-images`
>>   - [x] Linux x86_64 Zero release jcstress
>>   - [x] Linux aarch64 Zero release jcstress
>
> Aleksey Shipilev has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains one commit:
> 
>   8142984: Zero: fast accessors should handle both getters and setters

Looks good to me.

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Marked as reviewed by andrew (Reviewer).

PR: https://git.openjdk.java.net/jdk/pull/728