DO [,] CONCURRENT forall-header is a special loop variant with some extra constraints; in particular, it allows the compiler to run through the loop in any index order.
That's somewhat similar to FORALL (or at least to how FORALL is perceived) but avoids (a) temporaries (which FORALL often requires), (b) is no assignment feature (like FORALL) but a real loop, which allows for more things in the loop. First step is to implement the syntax and map DO CONCURRENT on a normal loop; I have a embryonic patch for this. Next step is to optimize for DO CONCURRENT (possibly thinking of automatic parallelization during -fopenmp/-ftree-parallelize-loops, etc.) Interpretation requests (main reason for opening this PR): http://j3-fortran.org/doc/meeting/192/10-172.txt http://j3-fortran.org/doc/meeting/192/10-173.txt http://j3-fortran.org/doc/meeting/192/10-175.txt http://j3-fortran.org/doc/meeting/192/10-176.txt -- Summary: [F2008] Implement DO CONCURRENT Product: gcc Version: 4.6.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: fortran AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: burnus at gcc dot gnu dot org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44646
