RFR: 8221477: Inject os/cpu-specific constants into Unsafe from JVM

[coleen.phillimore at oracle.com]

http://cr.openjdk.java.net/~adinn/8221477/webrev.02/src/hotspot/share/classfile/javaClasses.cpp.udiff.html

I was sort of expecting you to use like UNSAFE_CONSTANTS_DO for the 
fields, so that you don't have to add more names to vmSymbols.hpp. And 
that's what the rest of the code does (except CompactStrings). I can 
sort of  understand that it's faster as static_fields_do, and you can 
check for unexpected fields.

+ jint _address_size;
+ jint _page_size;
+ jboolean _big_endian;
+ jboolean _use_unaligned_access;

We've been trying to keep Java types out of the C++ code, and use the 
appropriate C++ types.

+ 
InstanceKlass::cast(SystemDictionary::UnsafeConstants_klass())->do_local_static_fields(&fixup);


The cast is unnecessary.  UnsafeConstants_klass returns an InstanceKlass.

http://cr.openjdk.java.net/~adinn/8221477/webrev.02/src/hotspot/share/classfile/vmSymbols.hpp.udiff.html

I just don't like the field names here. :(

Coleen

On 3/28/19 12:56 PM, Andrew Dinn wrote:
> On 28/03/2019 15:22, Thomas Stüfe wrote:
>>      The second of those was actually intended to be iff. This is a common
>>      abbreviation used by English/US mathematicians and logicians to write
>>      'if and only if' (it is also sometimes written as <=>). Since you didn't
>>      recognize it I guess I really need to write it out in full.
>>
>>
>> Oh, don't worry on my account. I am not a native speaker nor a
>> mathematician. You could leave iff and add [sic] to make everyone
>> curious and start googling "iff" :)
> I changed it nevertheless. It would be remiss to presume readers need be
> conversant with elliptical, English logico-mathematical parlance (I'm
> explaining this in as plain English as I can ... no, wait! ;-).
>
> Anyway, I addressed this and your other concerns in a new webrev.
>
>    JIRA:   https://bugs.openjdk.java.net/browse/JDK-8221477
>    Webrev: http://cr.openjdk.java.net/~adinn/8221477/webrev.02
>
> Input from a second reviewer would be welcome ...
>
> regards,
>
>
> Andrew Dinn
> -----------
> Senior Principal Software Engineer
> Red Hat UK Ltd
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