Re: OpenACC or OpenMP 4.0 target directives

[Tobias Burnus <burnus at net-b dot de>]

Güray Özen wrote:
> I came across a news about gcc will support OpenACC/OpenMP target
> directive. How can i download this version?

Well, the support is at an early stage, targetting several different 
backends. The work is done by several teams and, hence, not always very 
well coordinated. I think over the next months, it will improve as bits 
get merged into a common branch.

Some first steps to OpenACC support can be found in the GOMP-4_0-branch 
and in the openacc-1_0-branch branch.

The GOMP-4_0-branch bits aren't sufficient for offloading, yet. To my 
knowledge, the only publicly available implementation, which allows 
offloading is the openacc-1_0-branch, cf. 
http://gcc.gnu.org/ml/gcc/2013-10/msg00009.html

To try it, download either of the two branches and build GCC yourself; 
see bottom of http://gcc.gnu.org/wiki/GFortranBinaries#FromSource


> Moreover i'm going to ask question about optimization.

I think the first step is to actually get it working. Otherwise, the 
normal compiler optimizations are applied also to the target sections. I 
could imagine that there will also be some specific optimizations, e.g. 
with regards to copy/copyin/-out by avoiding unnecessary data transfers; 
however, I don't know whether such an optimization is already done in 
any of the branches.

Tobias