Part 1 Proposal for JDK-8264594

leerho leerho at
Fri May 28 21:37:57 UTC 2021


Again sorry about the delay.

Attached is a template proposal for the MemoryCopy class.

I can't complete this without your proposed new copyFrom(...) method in
MemorySegment. As it is written, it should work, but without the byte swap

I can complete the rest of the primitives like this template, if you would
like with javadocs.  I could also start writing tests, but without the

Let me know what would be most helpful.



On Thu, May 20, 2021 at 11:36 AM leerho <leerho at> wrote:

> Of course!
> On Thu, May 20, 2021 at 9:42 AM Maurizio Cimadamore <
> maurizio.cimadamore at> wrote:
>> On 20/05/2021 17:13, leerho wrote:
>> I am not sure if the *dstSegSlice* requires the *srcCopyLen*. I would
>> hope that it is smart enough to realize that the input length is smaller
>> than the given offset minus the segment size.
>> asSlice has an overload that just takes an offset and infers the
>> resulting size from there.
>> But that doesn't seem what you want here - as you want the slice to have
>> a specific size (the size of the input array).
>> MemorySegment::copyFrom wants the two segments to have the same size, so
>> I think you need that.
>> In terms of performance, there's no difference between asSlice(offset)
>> and asSlice(offset, size) - you have to create a new segment anyway.
>> Maurizio

More information about the panama-dev mailing list