RFR (S): 8191681: Unsafe accesses should use field_offset_to_byte_offset()

[Erik Österlund]

Hi Andrew,

On 2017-11-24 18:44, Andrew Haley wrote:
> On 24/11/17 14:45, Erik Österlund wrote:
>> Before the Access API, there was a no-op conversion function in
>> unsafe.cpp for getting the byte offset of a field offset from unsafe as
>> a jlong. Now, the field offsets *are* byte offsets, so the conversion
>> did not do anything. But I guess it could be useful nevertheless for
>> abstraction purposes.
> This came up when I was working on Unsafe, and I think it's really a
> bit of nonsense.  These days the byte offsets might even be absolute
> addresses, and the speculation that one day we might change our minds
> is rather pointless.  I could find the discussion from that thread if
> you're interested.
>

Thank you for your feedback. I would not mind dropping these changes in 
favour of simply assuming that Unsafe works with byte offsets only. My 
Access API changes introduced that assumption in this file by dodging 
the no-op conversion. Then I was asked to remove the assumption by 
re-introducing code performing the no-op conversion of field offsets to 
byte offsets. Personally I do not have a preference whether to perform 
or not perform this no-op conversion.

Thanks,
/Erik