Hi,

I.

This patch allows parallelization of an outer loop in an openacc kernels 
region.

The testcase is based on autopar/outer-1.c.


II.

We rely on pass_lim to move the *.omp_data_i loads out of the loop nest. 
For the test-case, pass_lim was managing to move the load out of the 
inner loop, but not the outer loop, because the load was classified as 
'MOVE_PRESERVE_EXECUTION'. By marking the *.omp_data_i load 
non-trapping, it's now classified as 'MOVE_POSSIBLE', and moved out of 
the loop nest.


III.

The 'loops_state_set (LOOPS_NEED_FIXUP)' is a somewhat blunt and 
temporary fix for the oacc kernels variant of PR66846 - parloops does 
not always mark loops for fixup if needed.

The original PR needs an added verify_loop_structure to trigger the 
problem. Normally the problem is hidden by the fact that the first pass 
that runs on the new function is pass_fixup_cfg, which happens to fixup 
the loops (The loops are fixed up because TODO_cleanup_cfg is set during 
pass_fixup_cfg, because the function contains an ECF_CONST function: 
__builtin_omp_get_num_threads).

For the oacc kernels variant, the problem triggers without adding 
verify_loop_structure. During pass_ipa_inline, we call 
loop_optimizer_init, which (given that LOOPS_NEED_FIXUP is not set) 
verifies the loop structure, which fails. Pass_fixup_cfg is not run 
inbetween the discovery of the new function and pass_ipa_inline.


IV.

I've committed this patch to gomp-4_0-branch.

Bootstrapped and reg-tested on x86_64. Build and reg-tested on setup 
with nvidia accelerator.

Thanks,
- Tom