System.arraycopy

[Deneau, Tom]

Christian --

For now just going for functionally correct, will address performance issues in the future.  But yes there are vector instructions that could help even in a single workitem.

Is there already a pure java implementation of System.arrayCopy we could substitute?

I guess we would want to use the logic to do different substitutions based on the type of the array (like in ArrayCopySnippets)?  

any other advice for implementing this?

-- Tom



> -----Original Message-----
> From: Christian Thalinger [mailto:christian.thalinger at oracle.com]
> Sent: Thursday, June 05, 2014 3:45 PM
> To: Deneau, Tom
> Cc: graal-dev at openjdk.java.net
> Subject: Re: System.arraycopy
> 
> Well, I guess the easiest but maybe not most performant way would be to
> have a substitution and implement it in plain Java.
> 
> On the other hand you could rely on vectorization and the power of GPUs
> to produce good, parallel code :-)
> 
> On Jun 5, 2014, at 1:29 PM, Deneau, Tom <tom.deneau at amd.com> wrote:
> 
> > Since we cannot handle "foreign calls" in the hsail backend, what is
> the preferred way to implement System.arraycopy?  Right now, we are
> deferring to the host and so getting an ArrayCopyCallNode which gets
> lowered to a graph containing a ForeignCallNode.
> >
> > I confess to being a little confused with the ArrayCopyNode and
> Snippets, UnsafeArrayCopyNode and Snippets, ArrayCopyCallNode, etc.
> >
> > -- Tom
> >