Ping.
> I've noticed while re-reading that this patch incorrectly handled SIMT case
> in lower_lastprivate_clauses. The code was changed to look for variables
> with "omp simt private" attribute, and was left under
> 'simduid && DECL_HAS_VALUE_EXPR_P (new_var)' condition. This effectively
> constrained processing to privatized (i.e. addressable) variables, as
> non-addressable variables now have neither the value-expr nor the attribute.
>
> This wasn't caught in testing, as apparently all testcases that have target
> simd loops with linear/lastprivate clauses also have the corresponding
> variables
> mentioned in target map clause, which makes them addressable (is that
> necessary?),
> and I didn't think to check something like that manually.
>
> The following patch fixes it by adjusting the if's in
> lower_lastprivate_clauses;
> alternatively it may be possible to keep that code as-is, and instead set up
> value-expr and "omp simt private" attributes for all formally private
> variables,
> not just addressable ones, but to me that sounds less preferable. OK for
> trunk?
>
> I think it's possible to improve test coverage for NVPTX by running all OpenMP
> testcases via nvptx-none-run (it'll need some changes, but shouldn't be hard).
>
> gcc/
> * omp-low.c (lower_lastprivate_clauses): Correct handling of linear and
> lastprivate clauses in SIMT case.
>
> libgomp/
> * testsuite/libgomp.c/target-36.c: New testcase.
>
> Thanks.
> Alexander
>
> diff --git a/gcc/omp-low.c b/gcc/omp-low.c
> index 253dc85..02b681c 100644
> --- a/gcc/omp-low.c
> +++ b/gcc/omp-low.c
> @@ -4768,11 +4768,10 @@ lower_lastprivate_clauses (tree clauses, tree
> predicate, gimple_seq *stmt_list,
> TREE_NO_WARNING (new_var) = 1;
> }
>
> - if (simduid && DECL_HAS_VALUE_EXPR_P (new_var))
> + if (!maybe_simt && simduid && DECL_HAS_VALUE_EXPR_P (new_var))
> {
> tree val = DECL_VALUE_EXPR (new_var);
> - if (!maybe_simt
> - && TREE_CODE (val) == ARRAY_REF
> + if (TREE_CODE (val) == ARRAY_REF
> && VAR_P (TREE_OPERAND (val, 0))
> && lookup_attribute ("omp simd array",
> DECL_ATTRIBUTES (TREE_OPERAND (val,
> @@ -4792,26 +4791,26 @@ lower_lastprivate_clauses (tree clauses, tree
> predicate, gimple_seq *stmt_list,
> TREE_OPERAND (val, 0), lastlane,
> NULL_TREE, NULL_TREE);
> }
> - else if (maybe_simt
> - && VAR_P (val)
> - && lookup_attribute ("omp simt private",
> - DECL_ATTRIBUTES (val)))
> + }
> + else if (maybe_simt)
> + {
> + tree val = (DECL_HAS_VALUE_EXPR_P (new_var)
> + ? DECL_VALUE_EXPR (new_var)
> + : new_var);
> + if (simtlast == NULL)
> {
> - if (simtlast == NULL)
> - {
> - simtlast = create_tmp_var (unsigned_type_node);
> - gcall *g = gimple_build_call_internal
> - (IFN_GOMP_SIMT_LAST_LANE, 1, simtcond);
> - gimple_call_set_lhs (g, simtlast);
> - gimple_seq_add_stmt (stmt_list, g);
> - }
> - x = build_call_expr_internal_loc
> - (UNKNOWN_LOCATION, IFN_GOMP_SIMT_XCHG_IDX,
> - TREE_TYPE (val), 2, val, simtlast);
> - new_var = unshare_expr (new_var);
> - gimplify_assign (new_var, x, stmt_list);
> - new_var = unshare_expr (new_var);
> + simtlast = create_tmp_var (unsigned_type_node);
> + gcall *g = gimple_build_call_internal
> + (IFN_GOMP_SIMT_LAST_LANE, 1, simtcond);
> + gimple_call_set_lhs (g, simtlast);
> + gimple_seq_add_stmt (stmt_list, g);
> }
> + x = build_call_expr_internal_loc
> + (UNKNOWN_LOCATION, IFN_GOMP_SIMT_XCHG_IDX,
> + TREE_TYPE (val), 2, val, simtlast);
> + new_var = unshare_expr (new_var);
> + gimplify_assign (new_var, x, stmt_list);
> + new_var = unshare_expr (new_var);
> }
>
> if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE
> diff --git a/libgomp/testsuite/libgomp.c/target-36.c
> b/libgomp/testsuite/libgomp.c/target-36.c
> new file mode 100644
> index 0000000..6925a2a
> --- /dev/null
> +++ b/libgomp/testsuite/libgomp.c/target-36.c
> @@ -0,0 +1,18 @@
> +int
> +main ()
> +{
> + int ah, bh, n = 1024;
> +#pragma omp target map(from: ah, bh)
> + {
> + int a, b;
> +#pragma omp simd lastprivate(b)
> + for (a = 0; a < n; a++)
> + {
> + b = a + n + 1;
> + asm volatile ("" : "+r"(b));
> + }
> + ah = a, bh = b;
> + }
> + if (ah != n || bh != 2 * n)
> + __builtin_abort ();
> +}
>
