Hi! OK to commit (something like) the following? Should something be added to the "News" section on <https://gcc.gnu.org/> itself? (I don't know the policy for that. We didn't suggest that for GCC 5, because at that time we described the support as a "preliminary implementation of the OpenACC 2.0a specification"; now it's much more complete and usable.)
Index: htdocs/gcc-6/changes.html =================================================================== RCS file: /cvs/gcc/wwwdocs/htdocs/gcc-6/changes.html,v retrieving revision 1.74 diff -u -p -r1.74 changes.html --- htdocs/gcc-6/changes.html 19 Apr 2016 11:13:02 -0000 1.74 +++ htdocs/gcc-6/changes.html 21 Apr 2016 16:10:49 -0000 @@ -124,6 +124,52 @@ For more information, see the <!-- .................................................................. --> <h2 id="languages">New Languages and Language specific improvements</h2> +<!-- <ul> + <li> -->Compared to GCC 5, the GCC 6 release series includes a much improved + implementation of the <a href="http://www.openacc.org/";>OpenACC 2.0a + specification</a>. Highlights are: + <ul> + <li>In addition to single-threaded host-fallback execution, offloading is + supported for nvptx (Nvidia GPUs) on x86_64 and PowerPC 64-bit + little-endian GNU/Linux host systems. For nvptx offloading, with the + OpenACC parallel construct, the execution model allows for an arbitrary + number of gangs, up to 32 workers, and 32 vectors.</li> + <li>Initial support for parallelized execution of OpenACC kernels + constructs: + <ul> + <li>Parallelization of a kernels region is switched on + by <code>-fopenacc</code> combined with <code>-O2</code> or + higher.</li> + <li>Code will be offloaded onto multiple gangs, but executes with + just one worker, and a vector length of 1.</li> + <li>Directives inside a kernels region are not supported.</li> + <li>Loops with reductions can be parallelized.</li> + <li>Only kernels regions with one loop nest are parallelized.</li> + <li>Only the outer-most loop of a loop nest can be parallelized.</li> + <li>Loop nests containing sibling loops are not parallelized.</li> + </ul> + Typically, using the OpenACC parallel construct will give much better + performance, compared to the initial support of the OpenACC kernels + construct. + <li>The <code>device_type</code> clause is not supported. + The <code>bind</code> and <code>nohost</code> clauses are not + supported. The <code>host_data</code> directive is not supported in + Fortran.</li> + <li>Nested parallelism (cf. CUDA dynamic parallelism) is not + supported.</li> + <li>Usage of OpenACC constructs inside multithreaded contexts (such as + created by OpenMP, or pthread programming) is not supported.</li> + <li>If a call to the <code>acc_on_device</code> function has a + compile-time constant argument, the function call evaluates to a + compile-time constant value only for C and C++ but not for + Fortran.</li> + </ul> + See the <a href="https://gcc.gnu.org/wiki/OpenACC";>OpenACC</a> + and <a href="https://gcc.gnu.org/wiki/Offloading";>Offloading</a> wiki pages + for further information. + <!-- </li> +</ul> --> + <!-- <h3 id="ada">Ada</h3> --> <h3 id="c-family">C family</h3> Grüße Thomas
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