Jakub,
this patch implements firstprivate support for openacc.  This is pretty straight 
forwards -- they're just regular auto variables, but with an initialization 
value from the host.

The gimplify.c implementation is somewhat different to gomp4 branch, as I've 
added new bits to enum omp_region_type, rather than add 2 new fields to 
omp_region_ctx.  The new enums use bits already defined in omp_region_type:

+  ORT_ACC = 0x40,  /* An OpenACC region.  */
+  ORT_ACC_DATA = ORT_ACC | ORT_TARGET_DATA, /* Data construct.  */
+  ORT_ACC_PARALLEL = ORT_ACC | ORT_TARGET,  /* Parallel construct */
+  ORT_ACC_KERNELS  = ORT_ACC | ORT_TARGET | 0x80,  /* Kernels construct.  */

On gomp4 we were already setting those bits, but then setting the new fields to 
indicate 'openacc'.  Many places in gimplify.c where we check for '== 
ORT_TARGET_DATA' or ORT_TARGET get changed to '& ORT_TARGET_DATA' etc.

On gomp4 for things like an openacc loop we were setting ORT_WORKSHARE, so 
nearly all checks for == ORT_WORKSHARE get an additional '|| X == ORT_ACC'.

Although this patch doesn't make use of the difference between ORT_ACC_KERNELS 
and ORT_ACC_PARALLEL, the default handling patch will -- they have different 
behaviours.

I think the gimpify.c changes are then obvious from that, but let me know.

in omp-low the changes are to remove 'sorry' and build the initializer exprs in 
lower_omp_target.

As you can see this fixes a few xfails.

I'll post the default handling patch, which is much more localized.

nathan