On Wed, Aug 26, 2015 at 04:56:23PM +0200, Richard Biener wrote:
> >> How do you declare those?
> >
> > Something like this:
> >
> > #pragma omp declare simd inbranch
> > int foo(int*);
>
> The 'inbranch' is the thing that matters? And all of foo is then
> implicitely predicated?
If it is
#pragma omp declare simd notinbranch,
then only the non-predicated version is emitted and thus it is usable only
in vectorized loops inside of non-conditional contexts.
If it is
#pragma omp declare simd inbranch,
then only the predicated version is emitted, there is an extra argument
(either V*QI if I remember well, or for AVX-512 short/int/long bitmask),
if the caller wants to use it in non-conditional contexts, it just passes
all ones mask. For
#pragma omp declare simd
(neither inbranch nor notinbranch), two versions are emitted, one predicated
and one non-predicated.
Jakub
