On 06/22/15 11:18, Bernd Schmidt wrote:
You can have a hint that it is desirable, but not a hint that it is correct (because passes in between may invalidate that). The OpenACC directives guarantee to the compiler that the program can be transformed into a parallel form. If we lose them early we must then rely on our analysis which may not be strong enough to prove that the loop can be parallelized. If we make these transformations early enough, while we still have the OpenACC directives, we can guarantee that we do exactly what the programmer specified.
How does this differ from openmp's needs to preserve parallelism on a parallel loop? Is it more than the reconvergence issue?
nathan -- Nathan Sidwell
