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Re: [patch,gomp-4_0-branch] openacc parallel reduction part 1
- From: Cesar Philippidis <cesar_philippidis at mentor dot com>
- To: Thomas Schwinge <thomas at codesourcery dot com>
- Cc: "gcc-patches at gcc dot gnu dot org" <gcc-patches at gcc dot gnu dot org>
- Date: Tue, 8 Jul 2014 07:28:24 -0700
- Subject: Re: [patch,gomp-4_0-branch] openacc parallel reduction part 1
- Authentication-results: sourceware.org; auth=none
- References: <53B9D780 dot 4040904 at mentor dot com> <87zjglsdc8 dot fsf at schwinge dot name>
On 07/07/2014 02:55 AM, Thomas Schwinge wrote:
> On Sun, 6 Jul 2014 16:10:56 -0700, Cesar Philippidis <cesar_philippidis@mentor.com> wrote:
>> This patch is the first step to enabling parallel reductions in openacc.
>
> Thanks!
>
>> As mentioned earlier, this patch isn't complete yet. For starters, parts
>> of it depends on our internal ptx backend. I've temporarily remapped the
>> ptx dependencies to their openmp equivalent, but without a proper
>> openacc runtime this infrastructure won't do much.
>
> For the curious: we're working on preparing our implementation of the
> OpenACC Runtime Library for upstream submission; if only the weeks had
> more days...
>
>> Thomas, is this patch OK for gomp-4_0-branch?
>
> I still :-( haven't managed to allocate the time for a proper review, but
> given this doesn't regress any existing test cases, it's fine to commit,
> and then we can take it from there.
>
> A few minor comments:
>
>> 2014-07-06 Cesar Philippidis <cesar@codesourcery.com>
>> Thomas Schwinge <thomas@codesourcery.com>
>
> By the way, on gomp-4_0-branch, ChangeLog snippets go into the respective
> ChangeLog.gomp files.
>
>> --- a/gcc/c/c-parser.c
>> +++ b/gcc/c/c-parser.c
>> @@ -11706,7 +11710,8 @@ c_parser_oacc_kernels (location_t loc, c_parser *parser, char *p_name)
>> */
>>
>> #define OACC_LOOP_CLAUSE_MASK \
>> - (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_NONE)
>> + ( (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_COLLAPSE) \
>
> Not yet. ;-)
>
>> + | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_REDUCTION))
>
>> --- a/gcc/fortran/types.def
>> +++ b/gcc/fortran/types.def
>> @@ -86,6 +86,7 @@ DEF_FUNCTION_TYPE_1 (BT_FN_UINT_UINT, BT_UINT, BT_UINT)
>> DEF_FUNCTION_TYPE_1 (BT_FN_PTR_PTR, BT_PTR, BT_PTR)
>> DEF_FUNCTION_TYPE_1 (BT_FN_VOID_INT, BT_VOID, BT_INT)
>> DEF_FUNCTION_TYPE_1 (BT_FN_BOOL_INT, BT_BOOL, BT_INT)
>> +DEF_FUNCTION_TYPE_1 (BT_FN_INT_INT, BT_INT, BT_INT)
>
> That one's not actually needed, because...
>
>> --- a/gcc/omp-builtins.def
>> +++ b/gcc/omp-builtins.def
>> @@ -236,3 +236,6 @@ DEF_GOMP_BUILTIN (BUILT_IN_GOMP_TARGET_UPDATE, "GOMP_target_update",
>> BT_FN_VOID_INT_PTR_SIZE_PTR_PTR_PTR, ATTR_NOTHROW_LIST)
>> DEF_GOMP_BUILTIN (BUILT_IN_GOMP_TEAMS, "GOMP_teams",
>> BT_FN_VOID_UINT_UINT, ATTR_NOTHROW_LIST)
>> +
>> +DEF_GOMP_BUILTIN (BUILT_IN_OMP_SET_NUM_THREADS, "omp_set_num_threads",
>> + BT_FN_INT_INT, ATTR_CONST_NOTHROW_LEAF_LIST)
>
> ... it's actually Âvoid omp_set_num_threads (int)Â, so BT_FN_VOID_INT.
> As this is only temporary code, please add a FIXME comment here. Hmm,
> and I wonder, given this is using DEF_*GOMP*_BUILTIN, does this actually
> do the right thing if -openmp is not specified?
Thanks for catching those problems! I've committed this updated version
of the patch.
Cesar
2014-07-08 Cesar Philippidis <cesar@codesourcery.com>
Thomas Schwinge <thomas@codesourcery.com>
gcc/
* omp-low.c (omp_get_id): New function.
(lookup_reduction): New function.
(maybe_lookup_reduction): New function.
(build_outer_var_ref): Remove openacc assert.
(new_omp_context): Preserve ctx->reduction_map.
(scan_sharing_clauses): Handle OMP_CLAUSE_REDUCTION.
(scan_oacc_offload): Initialize ctx->reduction_map.
(lower_reduction_clauses): Handle OpenACC reductions.
(omp_gimple_assign_with_ops): New function.
(initialize_reduction_data): New function.
(finalize_reduction_data): New function.
(process_reduction_data): New function.
(lower_oacc_offload): Handle reductions.
* gcc/omp-builtins.def (BUILT_IN_OMP_SET_NUM_THREADS): New.
gcc/c/
* c-parser.c (c_parser_oacc_all_clauses): Handle
PRAGMA_OMP_CLAUSE_REDUCTION.
(OACC_LOOP_CLAUSE_MASK, OACC_PARALLEL_CLAUSE_MASK): Add
PRAGMA_OMP_CLAUSE_REDUCTION.
gcc/testsuite/
* gcc/testsuite/c-c++-common/goacc/reduction-1.c: New test.
* gcc/testsuite/c-c++-common/goacc/reduction-2.c: New test.
* gcc/testsuite/c-c++-common/goacc/reduction-3.c: New test.
* gcc/testsuite/c-c++-common/goacc/reduction-4.c: New test.
diff --git a/gcc/c/c-parser.c b/gcc/c/c-parser.c
index 03852b4..6a9271f 100644
--- a/gcc/c/c-parser.c
+++ b/gcc/c/c-parser.c
@@ -11332,6 +11332,10 @@ c_parser_oacc_all_clauses (c_parser *parser, omp_clause_mask mask,
clauses = c_parser_oacc_data_clause (parser, c_kind, clauses);
c_name = "present_or_create";
break;
+ case PRAGMA_OMP_CLAUSE_REDUCTION:
+ clauses = c_parser_omp_clause_reduction (parser, clauses);
+ c_name = "reduction";
+ break;
case PRAGMA_OMP_CLAUSE_SELF:
clauses = c_parser_oacc_data_clause (parser, c_kind, clauses);
c_name = "self";
@@ -11706,7 +11710,7 @@ c_parser_oacc_kernels (location_t loc, c_parser *parser, char *p_name)
*/
#define OACC_LOOP_CLAUSE_MASK \
- (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_NONE)
+ (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_REDUCTION)
static tree
c_parser_oacc_loop (location_t loc, c_parser *parser, char *p_name)
@@ -11746,6 +11750,7 @@ c_parser_oacc_loop (location_t loc, c_parser *parser, char *p_name)
| (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_PRESENT_OR_COPYIN) \
| (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_PRESENT_OR_COPYOUT) \
| (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_PRESENT_OR_CREATE) \
+ | (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_REDUCTION) \
| (OMP_CLAUSE_MASK_1 << PRAGMA_OMP_CLAUSE_VECTOR_LENGTH) )
static tree
diff --git a/gcc/omp-builtins.def b/gcc/omp-builtins.def
index 08b825c..698dc79 100644
--- a/gcc/omp-builtins.def
+++ b/gcc/omp-builtins.def
@@ -236,3 +236,6 @@ DEF_GOMP_BUILTIN (BUILT_IN_GOMP_TARGET_UPDATE, "GOMP_target_update",
BT_FN_VOID_INT_PTR_SIZE_PTR_PTR_PTR, ATTR_NOTHROW_LIST)
DEF_GOMP_BUILTIN (BUILT_IN_GOMP_TEAMS, "GOMP_teams",
BT_FN_VOID_UINT_UINT, ATTR_NOTHROW_LIST)
+
+DEF_GOMP_BUILTIN (BUILT_IN_OMP_SET_NUM_THREADS, "omp_set_num_threads",
+ BT_FN_VOID_INT, ATTR_CONST_NOTHROW_LEAF_LIST)
diff --git a/gcc/omp-low.c b/gcc/omp-low.c
index cd27b76..219d5fe 100644
--- a/gcc/omp-low.c
+++ b/gcc/omp-low.c
@@ -158,6 +158,11 @@ typedef struct omp_context
construct. In the case of a parallel, this is in the child function. */
tree block_vars;
+ /* A map of reduction pointer variables. For accelerators, each
+ reduction variable is replaced with an array. Each thread, in turn,
+ is assigned to a slot on that array. */
+ splay_tree reduction_map;
+
/* Label to which GOMP_cancel{,llation_point} and explicit and implicit
barriers should jump to during omplower pass. */
tree cancel_label;
@@ -221,6 +226,17 @@ static tree scan_omp_1_op (tree *, int *, void *);
*handled_ops_p = false; \
break;
+/* Helper function to get the reduction array name */
+static const char *
+omp_get_id (tree node)
+{
+ const char *id = IDENTIFIER_POINTER (DECL_NAME (node));
+ int len = strlen ("omp$") + strlen (id);
+ char *temp_name = (char *)alloca (len+1);
+ snprintf (temp_name, len+1, "gfc$%s", id);
+ return IDENTIFIER_POINTER(get_identifier (temp_name));
+}
+
/* Holds a decl for __OPENMP_TARGET__. */
static GTY(()) tree offload_symbol_decl;
@@ -873,6 +889,17 @@ lookup_sfield (tree var, omp_context *ctx)
}
static inline tree
+lookup_reduction (const char *id, omp_context *ctx)
+{
+ gcc_assert (is_gimple_omp_oacc_specifically (ctx->stmt));
+
+ splay_tree_node n;
+ n = splay_tree_lookup (ctx->reduction_map,
+ (splay_tree_key) id);
+ return (tree) n->value;
+}
+
+static inline tree
maybe_lookup_field (tree var, omp_context *ctx)
{
splay_tree_node n;
@@ -880,6 +907,17 @@ maybe_lookup_field (tree var, omp_context *ctx)
return n ? (tree) n->value : NULL_TREE;
}
+static inline tree
+maybe_lookup_reduction (tree var, omp_context *ctx)
+{
+ gcc_assert (is_gimple_omp_oacc_specifically (ctx->stmt));
+
+ splay_tree_node n;
+ n = splay_tree_lookup (ctx->reduction_map,
+ (splay_tree_key) var);
+ return n ?(tree) n->value : NULL_TREE;
+}
+
/* Return true if DECL should be copied by pointer. SHARED_CTX is
the parallel context if DECL is to be shared. */
@@ -1036,8 +1074,6 @@ build_receiver_ref (tree var, bool by_ref, omp_context *ctx)
static tree
build_outer_var_ref (tree var, omp_context *ctx)
{
- gcc_assert (!is_gimple_omp_oacc_specifically (ctx->stmt));
-
tree x;
if (is_global_var (maybe_lookup_decl_in_outer_ctx (var, ctx)))
@@ -1379,6 +1415,8 @@ new_omp_context (gimple stmt, omp_context *outer_ctx)
ctx->cb = outer_ctx->cb;
ctx->cb.block = NULL;
ctx->depth = outer_ctx->depth + 1;
+ /* FIXME: handle reductions recursively. */
+ ctx->reduction_map = outer_ctx->reduction_map;
}
else
{
@@ -1392,6 +1430,7 @@ new_omp_context (gimple stmt, omp_context *outer_ctx)
ctx->cb.eh_lp_nr = 0;
ctx->cb.transform_call_graph_edges = CB_CGE_MOVE;
ctx->depth = 1;
+ //TODO ctx->reduction_map = TODO;
}
ctx->cb.decl_map = pointer_map_create ();
@@ -1588,7 +1627,6 @@ scan_sharing_clauses (tree clauses, omp_context *ctx)
/* FALLTHRU */
case OMP_CLAUSE_FIRSTPRIVATE:
- case OMP_CLAUSE_REDUCTION:
if (is_gimple_omp_oacc_specifically (ctx->stmt))
{
sorry ("clause not supported yet");
@@ -1596,6 +1634,7 @@ scan_sharing_clauses (tree clauses, omp_context *ctx)
}
case OMP_CLAUSE_LINEAR:
gcc_assert (!is_gimple_omp_oacc_specifically (ctx->stmt));
+ case OMP_CLAUSE_REDUCTION:
decl = OMP_CLAUSE_DECL (c);
do_private:
if (is_variable_sized (decl))
@@ -1621,6 +1660,28 @@ scan_sharing_clauses (tree clauses, omp_context *ctx)
install_var_field (decl, by_ref, 3, ctx);
}
install_var_local (decl, ctx);
+ //TODO
+ if (is_gimple_omp_oacc_specifically (ctx->stmt))
+ {
+ if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION)
+ {
+ /* Create a decl for the reduction array. */
+ tree var = OMP_CLAUSE_DECL (c);
+ tree ptype = build_pointer_type (TREE_TYPE (var));
+ tree array = create_tmp_var (ptype, omp_get_id (var));
+ omp_context *c = (ctx->field_map ? ctx : ctx->outer);
+ install_var_field (array, true, 3, c);
+ install_var_local (array, c);
+
+ /* Insert it into the current context. */
+ splay_tree_insert (ctx->reduction_map,
+ (splay_tree_key) omp_get_id(var),
+ (splay_tree_value) array);
+ splay_tree_insert (ctx->reduction_map,
+ (splay_tree_key) array,
+ (splay_tree_value) array);
+ }
+ }
break;
case OMP_CLAUSE__LOOPTEMP_:
@@ -1658,10 +1719,7 @@ scan_sharing_clauses (tree clauses, omp_context *ctx)
case OMP_CLAUSE_NUM_WORKERS:
case OMP_CLAUSE_VECTOR_LENGTH:
if (ctx->outer)
- {
- gcc_assert (!is_gimple_omp_oacc_specifically (ctx->stmt));
scan_omp_op (&OMP_CLAUSE_OPERAND (c, 0), ctx->outer);
- }
break;
case OMP_CLAUSE_TO:
@@ -1750,7 +1808,16 @@ scan_sharing_clauses (tree clauses, omp_context *ctx)
&& TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
install_var_field (decl, true, 7, ctx);
else
- install_var_field (decl, true, 3, ctx);
+ {
+ if (!is_gimple_omp_oacc_specifically (ctx->stmt))
+ install_var_field (decl, true, 3, ctx);
+ else
+ {
+ /* decl goes heres. */
+ omp_context *c = (ctx->field_map ? ctx : ctx->outer);
+ install_var_field (decl, true, 3, c);
+ }
+ }
if (is_gimple_omp_offloaded (ctx->stmt))
install_var_local (decl, ctx);
}
@@ -1844,7 +1911,6 @@ scan_sharing_clauses (tree clauses, omp_context *ctx)
/* FALLTHRU */
case OMP_CLAUSE_FIRSTPRIVATE:
- case OMP_CLAUSE_REDUCTION:
if (is_gimple_omp_oacc_specifically (ctx->stmt))
{
sorry ("clause not supported yet");
@@ -1852,6 +1918,7 @@ scan_sharing_clauses (tree clauses, omp_context *ctx)
}
case OMP_CLAUSE_LINEAR:
gcc_assert (!is_gimple_omp_oacc_specifically (ctx->stmt));
+ case OMP_CLAUSE_REDUCTION:
case OMP_CLAUSE_PRIVATE:
decl = OMP_CLAUSE_DECL (c);
if (is_variable_sized (decl))
@@ -2161,6 +2228,7 @@ scan_oacc_offload (gimple stmt, omp_context *outer_ctx)
DECL_NAMELESS (name) = 1;
TYPE_NAME (ctx->record_type) = name;
create_omp_child_function (ctx, false);
+ ctx->reduction_map = splay_tree_new (splay_tree_compare_pointers, 0, 0);
gimple_omp_set_child_fn (stmt, ctx->cb.dst_fn);
@@ -4211,6 +4279,8 @@ lower_reduction_clauses (tree clauses, gimple_seq *stmt_seqp, omp_context *ctx)
if (count == 1)
{
+ if (!is_gimple_omp_oacc_specifically (ctx->stmt))
+ {
tree addr = build_fold_addr_expr_loc (clause_loc, ref);
addr = save_expr (addr);
@@ -4219,6 +4289,117 @@ lower_reduction_clauses (tree clauses, gimple_seq *stmt_seqp, omp_context *ctx)
x = build2 (OMP_ATOMIC, void_type_node, addr, x);
gimplify_and_add (x, stmt_seqp);
return;
+ }
+ else
+ {
+ /* The atomic add at the end of the sum creates unnecessary
+ write contention on accelerators. To work around that,
+ create an array or vector_length and assign an element to
+ each thread. Later, in lower_omp_for (for openacc), the
+ values of array will be combined. */
+
+ tree t = NULL_TREE, array, nthreads;
+
+ /* First ensure that the current tid is less than vector_length. */
+ tree exit_label = create_artificial_label (UNKNOWN_LOCATION);
+ tree reduction_label = create_artificial_label (UNKNOWN_LOCATION);
+
+ /* Get the current thread id. */
+ tree call = builtin_decl_explicit (BUILT_IN_OMP_GET_THREAD_NUM);
+ gimple stmt = gimple_build_call (call, 1, integer_zero_node);
+ tree fntype = gimple_call_fntype (stmt);
+ tree tid = create_tmp_var (TREE_TYPE (fntype), NULL);
+ gimple_call_set_lhs (stmt, tid);
+ gimple_seq_add_stmt (stmt_seqp, stmt);
+
+ /* Find the total number of threads. A reduction clause
+ only appears inside a loop construction or a combined
+ parallel and loop construct. */
+ tree c;
+
+ if (gimple_code (ctx->stmt) == GIMPLE_OMP_FOR)
+ c = gimple_oacc_parallel_clauses (ctx->outer->stmt);
+ else
+ c = gimple_oacc_parallel_clauses (ctx->stmt);
+
+ t = find_omp_clause (c, OMP_CLAUSE_VECTOR_LENGTH);
+
+ if (t)
+ {
+ t = fold_convert_loc (OMP_CLAUSE_LOCATION (t),
+ integer_type_node,
+ OMP_CLAUSE_VECTOR_LENGTH_EXPR (t));
+ }
+
+ if (!t)
+ t = integer_one_node;
+
+ /* Extract the number of threads. */
+ nthreads = create_tmp_var (sizetype, NULL);
+ gimplify_assign (nthreads, fold_build1 (NOP_EXPR, sizetype, t),
+ stmt_seqp);
+ stmt = gimple_build_assign_with_ops (MINUS_EXPR, nthreads, nthreads,
+ fold_build1 (NOP_EXPR, sizetype,
+ integer_one_node));
+ gimple_seq_add_stmt (stmt_seqp, stmt);
+
+ /* If tid >= nthreads, goto exit_label. */
+ t = create_tmp_var (sizetype, NULL);
+ gimplify_assign (t, fold_build1 (NOP_EXPR, sizetype, tid),
+ stmt_seqp);
+ stmt = gimple_build_cond (GT_EXPR, t, nthreads, exit_label,
+ reduction_label);
+ gimple_seq_add_stmt (stmt_seqp, stmt);
+
+ /* Place the reduction_label here. */
+
+ gimple_seq_add_stmt (stmt_seqp,
+ gimple_build_label (reduction_label));
+
+ /* Now insert the partial reductions into the array. */
+
+ /* Create an array for the reduction variable and install it
+ in the parent scope. */
+ tree ptype = build_pointer_type (TREE_TYPE (var));
+
+ t = lookup_reduction (omp_get_id (var), ctx);
+ t = build_receiver_ref (t, false, ctx->outer);
+
+ array = create_tmp_var (ptype, NULL);
+ gimplify_assign (array, t, stmt_seqp);
+
+ tree ptr = create_tmp_var (TREE_TYPE (array), NULL);
+
+ /* Find the reduction array. */
+
+ /* testing a unary conversion. */
+ tree offset = create_tmp_var (sizetype, NULL);
+ gimplify_assign (offset, TYPE_SIZE_UNIT (TREE_TYPE (var)),
+ stmt_seqp);
+ t = create_tmp_var (sizetype, NULL);
+ gimplify_assign (t, unshare_expr (fold_build1 (NOP_EXPR, sizetype,
+ tid)),
+ stmt_seqp);
+ stmt = gimple_build_assign_with_ops (MULT_EXPR, offset, offset, t);
+ gimple_seq_add_stmt (stmt_seqp, stmt);
+
+ /* Offset expression. Does the POINTER_PLUS_EXPR take care
+ of adding sizeof(var) to the array? */
+ ptr = create_tmp_var (ptype, NULL);
+ stmt = gimple_build_assign_with_ops (POINTER_PLUS_EXPR,
+ unshare_expr(ptr),
+ array, offset);
+ gimple_seq_add_stmt (stmt_seqp, stmt);
+
+ /* Move the local sum to gfc$sum[i]. */
+ x = unshare_expr (build_simple_mem_ref (ptr));
+ stmt = gimplify_assign (x, new_var, stmt_seqp);
+
+ /* Place exit label here. */
+ gimple_seq_add_stmt (stmt_seqp, gimple_build_label (exit_label));
+
+ return;
+ }
}
if (OMP_CLAUSE_REDUCTION_PLACEHOLDER (c))
@@ -9138,6 +9319,410 @@ make_pass_expand_omp (gcc::context *ctxt)
return new pass_expand_omp (ctxt);
}
+/* Helper function to preform, potentially COMPLEX_TYPE, operation and
+ convert it to gimple. */
+static void
+omp_gimple_assign_with_ops (tree_code op, tree dest, tree src, gimple_seq *seq)
+{
+ gimple stmt;
+
+ if (TREE_CODE (TREE_TYPE (dest)) != COMPLEX_TYPE)
+ {
+ stmt = gimple_build_assign_with_ops (op, dest, dest, src);
+ gimple_seq_add_stmt (seq, stmt);
+ return;
+ }
+
+ tree t = create_tmp_var (TREE_TYPE (TREE_TYPE (dest)), NULL);
+ tree rdest = fold_build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (dest)), dest);
+ gimplify_assign (t, rdest, seq);
+ rdest = t;
+
+ t = create_tmp_var (TREE_TYPE (TREE_TYPE (dest)), NULL);
+ tree idest = fold_build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (dest)), dest);
+ gimplify_assign (t, idest, seq);
+ idest = t;
+
+ t = create_tmp_var (TREE_TYPE (TREE_TYPE (src)), NULL);
+ tree rsrc = fold_build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (src)), src);
+ gimplify_assign (t, rsrc, seq);
+ rsrc = t;
+
+ t = create_tmp_var (TREE_TYPE (TREE_TYPE (src)), NULL);
+ tree isrc = fold_build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (src)), src);
+ gimplify_assign (t, isrc, seq);
+ isrc = t;
+
+ tree r = create_tmp_var (TREE_TYPE (TREE_TYPE (dest)), NULL);
+ tree i = create_tmp_var (TREE_TYPE (TREE_TYPE (dest)), NULL);
+ tree result;
+
+ gcc_assert (op == PLUS_EXPR || op == MULT_EXPR);
+
+ if (op == PLUS_EXPR)
+ {
+ stmt = gimple_build_assign_with_ops (op, r, rdest, rsrc);
+ gimple_seq_add_stmt (seq, stmt);
+
+ stmt = gimple_build_assign_with_ops (op, i, idest, isrc);
+ gimple_seq_add_stmt (seq, stmt);
+ }
+ else if (op == MULT_EXPR)
+ {
+ /* Let x = a + ib = dest, y = c + id = src.
+ x * y = (ac - bd) + i(ad + bc) */
+ tree ac = create_tmp_var (TREE_TYPE (TREE_TYPE (dest)), NULL);
+ tree bd = create_tmp_var (TREE_TYPE (TREE_TYPE (dest)), NULL);
+ tree ad = create_tmp_var (TREE_TYPE (TREE_TYPE (dest)), NULL);
+ tree bc = create_tmp_var (TREE_TYPE (TREE_TYPE (dest)), NULL);
+
+ stmt = gimple_build_assign_with_ops (MULT_EXPR, ac, rdest, rsrc);
+ gimple_seq_add_stmt (seq, stmt);
+
+ stmt = gimple_build_assign_with_ops (MULT_EXPR, bd, idest, isrc);
+ gimple_seq_add_stmt (seq, stmt);
+
+ stmt = gimple_build_assign_with_ops (MINUS_EXPR, r, ac, bd);
+ gimple_seq_add_stmt (seq, stmt);
+
+ stmt = gimple_build_assign_with_ops (MULT_EXPR, ad, rdest, isrc);
+ gimple_seq_add_stmt (seq, stmt);
+
+ stmt = gimple_build_assign_with_ops (MULT_EXPR, bd, idest, rsrc);
+ gimple_seq_add_stmt (seq, stmt);
+
+ stmt = gimple_build_assign_with_ops (PLUS_EXPR, i, ad, bc);
+ gimple_seq_add_stmt (seq, stmt);
+ }
+
+ result = build2 (COMPLEX_EXPR, TREE_TYPE (dest), r, i);
+ gimplify_assign (dest, result, seq);
+}
+
+/* Helper function to initialize local data for the reduction arrays.
+ The reduction arrays need to be placed inside the calling function
+ for accelerators, or else the host won't be able to preform the final
+ reduction. FIXME: This function assumes that there are
+ vector_length threads in total. */
+
+static void
+initialize_reduction_data (tree clauses, tree nthreads, gimple_seq *stmt_seqp,
+ omp_context *ctx)
+{
+ gcc_assert (is_gimple_omp_oacc_specifically (ctx->stmt));
+
+ tree c, t, oc;
+ gimple stmt;
+ omp_context *octx;
+ tree (*gimple_omp_clauses) (const_gimple);
+ void (*gimple_omp_set_clauses) (gimple, tree);
+
+ /* Find the innermost PARALLEL openmp context. FIXME: OpenACC kernels
+ may require extra care unless they are converted to openmp for loops. */
+
+ if (gimple_code (ctx->stmt) == GIMPLE_OACC_PARALLEL)
+ octx = ctx;
+ else
+ octx = ctx->outer;
+
+ gimple_omp_clauses = gimple_oacc_parallel_clauses;
+ gimple_omp_set_clauses = gimple_oacc_parallel_set_clauses;
+
+ /* Extract the clauses. */
+ oc = gimple_omp_clauses (octx->stmt);
+
+ /* Find the last outer clause. */
+ for (; oc && OMP_CLAUSE_CHAIN (oc); oc = OMP_CLAUSE_CHAIN (oc))
+ ;
+
+ /* Allocate arrays for each reduction variable. */
+ for (c = clauses; c; c = OMP_CLAUSE_CHAIN (c))
+ {
+ if (OMP_CLAUSE_CODE (c) != OMP_CLAUSE_REDUCTION)
+ continue;
+
+ tree var = OMP_CLAUSE_DECL (c);
+ tree array = lookup_reduction (omp_get_id (var), ctx);
+ tree size, call;
+
+ /* Calculate size of the reduction array. */
+ t = create_tmp_var (TREE_TYPE (nthreads), NULL);
+ stmt = gimple_build_assign_with_ops (MULT_EXPR, t, nthreads,
+ fold_convert (TREE_TYPE (nthreads),
+ TYPE_SIZE_UNIT (TREE_TYPE (var))));
+ gimple_seq_add_stmt (stmt_seqp, stmt);
+
+ size = create_tmp_var (sizetype, NULL);
+ gimplify_assign (size, fold_build1 (NOP_EXPR, sizetype, t), stmt_seqp);
+
+ /* Now allocate memory for it. FIXME: Allocating memory for the
+ reduction array may be unnecessary once the final reduction is able
+ to be preformed on the accelerator. Instead of allocating memory on
+ the host side, it could just be allocated on the accelerator. */
+ call = unshare_expr (builtin_decl_explicit (BUILT_IN_ALLOCA));
+ stmt = gimple_build_call (call, 1, size);
+ gimple_call_set_lhs (stmt, array);
+ gimple_seq_add_stmt (stmt_seqp, stmt);
+
+ /* Map this array into the accelerator. */
+
+ /* Add the reduction array to the list of clauses. */
+ /* FIXME: Currently, these variables must be placed in the outer
+ most clause so that copy-out works. */
+ tree x = array;
+ t = build_omp_clause (gimple_location (ctx->stmt), OMP_CLAUSE_MAP);
+ OMP_CLAUSE_MAP_KIND (t) = OMP_CLAUSE_MAP_FORCE_FROM;
+ OMP_CLAUSE_DECL (t) = x;
+ OMP_CLAUSE_CHAIN (t) = NULL;
+ if (oc)
+ OMP_CLAUSE_CHAIN (oc) = t;
+ else
+ gimple_omp_set_clauses (octx->stmt, t);
+ OMP_CLAUSE_SIZE (t) = size;
+ oc = t;
+ }
+}
+
+/* Helper function to finalize local data for the reduction arrays. The
+ reduction array needs to be reduced to the original reduction variable.
+ FIXME: This function assumes that there are vector_length threads in
+ total. Also, it assumes that there are at least vector_length iterations
+ in the for loop. */
+
+static void
+finalize_reduction_data (tree clauses, tree nthreads, gimple_seq *stmt_seqp,
+ omp_context *ctx)
+{
+ gcc_assert (is_gimple_omp_oacc_specifically (ctx->stmt));
+
+ tree c, var, array, loop_header, loop_body, loop_exit;
+ gimple stmt;
+
+ /* Create for loop.
+
+ let var = the original reduction variable
+ let array = reduction variable array
+
+ var = array[0]
+ for (i = 1; i < nthreads; i++)
+ var op= array[i]
+ */
+
+ loop_header = create_artificial_label (UNKNOWN_LOCATION);
+ loop_body = create_artificial_label (UNKNOWN_LOCATION);
+ loop_exit = create_artificial_label (UNKNOWN_LOCATION);
+
+ /* Initialize the reduction variables to be value of the first array
+ element. */
+ for (c = clauses; c; c = OMP_CLAUSE_CHAIN (c))
+ {
+ if (OMP_CLAUSE_CODE (c) != OMP_CLAUSE_REDUCTION)
+ continue;
+
+ tree_code reduction_code = OMP_CLAUSE_REDUCTION_CODE (c);
+
+ /* reduction(-:var) sums up the partial results, so it acts
+ identically to reduction(+:var). */
+ if (reduction_code == MINUS_EXPR)
+ reduction_code = PLUS_EXPR;
+
+ /* Set up reduction variable, var. Becuase it's not gimple register,
+ it needs to be treated as a reference. */
+ var = OMP_CLAUSE_DECL (c);
+
+ tree ptr = lookup_reduction (omp_get_id (OMP_CLAUSE_DECL (c)), ctx);
+
+ /* Extract array[ix] into mem. */
+ tree mem = create_tmp_var (TREE_TYPE (var), NULL);
+ gimplify_assign (mem, build_simple_mem_ref (ptr), stmt_seqp);
+
+ /* Find the original reduction variable. */
+ tree new_var = lookup_decl (var, ctx);
+ tree x = build_outer_var_ref (var, ctx);
+ if (is_reference (var))
+ new_var = build_simple_mem_ref (new_var);
+
+ x = lang_hooks.decls.omp_clause_assign_op (c, var, mem);
+ gimplify_and_add (unshare_expr(x), stmt_seqp);
+ }
+
+ /* Create an index variable and set it to one. */
+ tree ix = create_tmp_var (sizetype, NULL);
+ gimplify_assign (ix, fold_build1 (NOP_EXPR, sizetype, integer_one_node),
+ stmt_seqp);
+
+ /* Insert the loop header label here. */
+ gimple_seq_add_stmt (stmt_seqp, gimple_build_label (loop_header));
+
+ /* Loop if ix >= nthreads. */
+ tree x = create_tmp_var (sizetype, NULL);
+ gimplify_assign (x, fold_build1 (NOP_EXPR, sizetype, nthreads), stmt_seqp);
+ stmt = gimple_build_cond (GE_EXPR, ix, x, loop_exit, loop_body);
+ gimple_seq_add_stmt (stmt_seqp, stmt);
+
+ /* Insert the loop body label here. */
+ gimple_seq_add_stmt (stmt_seqp, gimple_build_label (loop_body));
+
+ /* Collapse each reduction array, one element at a time. */
+ for (c = clauses; c; c = OMP_CLAUSE_CHAIN (c))
+ {
+ if (OMP_CLAUSE_CODE (c) != OMP_CLAUSE_REDUCTION)
+ continue;
+
+ tree_code reduction_code = OMP_CLAUSE_REDUCTION_CODE (c);
+
+ /* reduction(-:var) sums up the partial results, so it acts
+ identically to reduction(+:var). */
+ if (reduction_code == MINUS_EXPR)
+ reduction_code = PLUS_EXPR;
+
+ /* Set up reduction variable var. */
+ var = OMP_CLAUSE_DECL (c);
+
+ array = lookup_reduction (omp_get_id (OMP_CLAUSE_DECL (c)), ctx);
+
+ /* Calculate the array offset. */
+ tree offset = create_tmp_var (sizetype, NULL);
+ gimplify_assign (offset, TYPE_SIZE_UNIT (TREE_TYPE (var)), stmt_seqp);
+ stmt = gimple_build_assign_with_ops (MULT_EXPR, offset, offset, ix);
+ gimple_seq_add_stmt (stmt_seqp, stmt);
+
+ tree ptr = create_tmp_var (TREE_TYPE (array), NULL);
+ stmt = gimple_build_assign_with_ops (POINTER_PLUS_EXPR, ptr, array,
+ offset);
+ gimple_seq_add_stmt (stmt_seqp, stmt);
+
+ /* Extract array[ix] into mem. */
+ tree mem = create_tmp_var (TREE_TYPE (var), NULL);
+ gimplify_assign (mem, build_simple_mem_ref (ptr), stmt_seqp);
+
+ /* Find the original reduction variable. */
+ tree new_var = lookup_decl (var, ctx);
+ tree x = build_outer_var_ref (var, ctx);
+ if (is_reference (var))
+ new_var = build_simple_mem_ref (new_var);
+
+ tree t = create_tmp_var (TREE_TYPE (var), NULL);
+
+ x = lang_hooks.decls.omp_clause_assign_op (c, t, var);
+ gimplify_and_add (unshare_expr(x), stmt_seqp);
+
+ /* var = var op mem */
+ switch (OMP_CLAUSE_REDUCTION_CODE (c))
+ {
+ case TRUTH_ANDIF_EXPR:
+ case TRUTH_ORIF_EXPR:
+ t = fold_build2 (OMP_CLAUSE_REDUCTION_CODE (c), integer_type_node,
+ t, mem);
+ gimplify_and_add (t, stmt_seqp);
+ break;
+ default:
+ /* The lhs isn't a gimple_reg when var is COMPLEX_TYPE. */
+ omp_gimple_assign_with_ops (OMP_CLAUSE_REDUCTION_CODE (c),
+ t, mem, stmt_seqp);
+ }
+
+ t = fold_build1 (NOP_EXPR, TREE_TYPE (var), t);
+ x = lang_hooks.decls.omp_clause_assign_op (c, var, t);
+ gimplify_and_add (unshare_expr(x), stmt_seqp);
+ }
+
+ /* Increment the induction variable. */
+ tree one = fold_build1 (NOP_EXPR, sizetype, integer_one_node);
+ stmt = gimple_build_assign_with_ops (PLUS_EXPR, ix, ix, one);
+ gimple_seq_add_stmt (stmt_seqp, stmt);
+
+ /* Go back to the top of the loop. */
+ gimple_seq_add_stmt (stmt_seqp, gimple_build_goto (loop_header));
+
+ /* Place the loop exit label here. */
+ gimple_seq_add_stmt (stmt_seqp, gimple_build_label (loop_exit));
+}
+
+/* Scan through all of the gimple stmts searching for an OMP_FOR_EXPR, and
+ scan that for reductions. */
+
+static void
+process_reduction_data (gimple_seq *body, gimple_seq *in_stmt_seqp,
+ gimple_seq *out_stmt_seqp, omp_context *ctx)
+{
+ gcc_assert (is_gimple_omp_oacc_specifically (ctx->stmt));
+
+ gimple_stmt_iterator gsi;
+
+ for (gsi = gsi_start (*body); !gsi_end_p (gsi); gsi_next (&gsi))
+ {
+ gimple stmt = gsi_stmt (gsi);
+ tree call;
+
+ switch (gimple_code (stmt))
+ {
+ case GIMPLE_OMP_FOR:
+ tree clauses, nthreads, t;
+
+ clauses = gimple_omp_for_clauses (stmt);
+ ctx = maybe_lookup_ctx (stmt);
+ t = NULL_TREE;
+
+ /* The reduction clause may be nested inside a loop directive.
+ Scan for the innermost vector_length clause. */
+ for (omp_context *oc = ctx; oc; oc = oc->outer)
+ {
+ tree c;
+
+ switch (gimple_code (oc->stmt))
+ {
+ case GIMPLE_OACC_PARALLEL:
+ c = gimple_oacc_parallel_clauses (oc->stmt);
+ break;
+ case GIMPLE_OMP_FOR:
+ c = gimple_omp_for_clauses (oc->stmt);
+ break;
+ default:
+ c = NULL_TREE;
+ break;
+ }
+
+ if (c && gimple_code (oc->stmt) == GIMPLE_OACC_PARALLEL)
+ {
+ t = find_omp_clause (c, OMP_CLAUSE_VECTOR_LENGTH);
+ if (t)
+ t = fold_convert_loc (OMP_CLAUSE_LOCATION (t),
+ integer_type_node,
+ OMP_CLAUSE_VECTOR_LENGTH_EXPR (t));
+ break;
+ }
+ }
+
+ if (!t)
+ t = integer_one_node;
+
+ /* Extract the number of threads. */
+ nthreads = create_tmp_var (TREE_TYPE (t), NULL);
+ gimplify_assign (nthreads, t, in_stmt_seqp);
+
+ /* Ensure nthreads >= 1. */
+ stmt = gimple_build_assign_with_ops (MAX_EXPR, nthreads, nthreads,
+ fold_convert(TREE_TYPE (nthreads),
+ integer_one_node));
+ gimple_seq_add_stmt (in_stmt_seqp, stmt);
+
+ /* Set the number of threads. */
+ /* FIXME: This needs to handle accelerators */
+ call = builtin_decl_explicit (BUILT_IN_OMP_SET_NUM_THREADS);
+ stmt = gimple_build_call (call, 1, nthreads);
+ gimple_seq_add_stmt (in_stmt_seqp, stmt);
+
+ initialize_reduction_data (clauses, nthreads, in_stmt_seqp, ctx);
+ finalize_reduction_data (clauses, nthreads, out_stmt_seqp, ctx);
+ break;
+ default:
+ // Scan for other directives which support reduction here.
+ break;
+ }
+ }
+}
+
/* Routines to lower OpenMP directives into OMP-GIMPLE. */
/* Lower the OpenACC offload directive in the current statement
@@ -9150,7 +9735,7 @@ lower_oacc_offload (gimple_stmt_iterator *gsi_p, omp_context *ctx)
tree child_fn, t, c;
gimple stmt = gsi_stmt (*gsi_p);
gimple par_bind, bind;
- gimple_seq par_body, olist, ilist, new_body;
+ gimple_seq par_body, olist, ilist, orlist, irlist, new_body;
location_t loc = gimple_location (stmt);
unsigned int map_cnt = 0;
tree (*gimple_omp_clauses) (const_gimple);
@@ -9176,6 +9761,10 @@ lower_oacc_offload (gimple_stmt_iterator *gsi_p, omp_context *ctx)
push_gimplify_context ();
+ irlist = NULL;
+ orlist = NULL;
+ process_reduction_data (&par_body, &irlist, &orlist, ctx);
+
for (c = clauses; c ; c = OMP_CLAUSE_CHAIN (c))
switch (OMP_CLAUSE_CODE (c))
{
@@ -9330,7 +9919,8 @@ lower_oacc_offload (gimple_stmt_iterator *gsi_p, omp_context *ctx)
avar = build_fold_addr_expr (avar);
gimplify_assign (x, avar, &ilist);
}
- else if (is_gimple_reg (var))
+ else if (is_gimple_reg (var)
+ && !maybe_lookup_reduction (var, ctx))
{
tree avar = create_tmp_var (TREE_TYPE (var), NULL);
mark_addressable (avar);
@@ -9355,7 +9945,8 @@ lower_oacc_offload (gimple_stmt_iterator *gsi_p, omp_context *ctx)
}
else
{
- var = build_fold_addr_expr (var);
+ if (!maybe_lookup_reduction (var, ctx))
+ var = build_fold_addr_expr (var);
gimplify_assign (x, var, &ilist);
}
}
@@ -9439,9 +10030,11 @@ lower_oacc_offload (gimple_stmt_iterator *gsi_p, omp_context *ctx)
bind = gimple_build_bind (NULL, NULL, gimple_bind_block (par_bind));
gsi_replace (gsi_p, bind, true);
+ gimple_bind_add_seq (bind, irlist);
gimple_bind_add_seq (bind, ilist);
gimple_bind_add_stmt (bind, stmt);
gimple_bind_add_seq (bind, olist);
+ gimple_bind_add_seq (bind, orlist);
pop_gimplify_context (NULL);
}
diff --git a/gcc/testsuite/c-c++-common/goacc/reduction-1.c b/gcc/testsuite/c-c++-common/goacc/reduction-1.c
new file mode 100644
index 0000000..cff7d2d
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/goacc/reduction-1.c
@@ -0,0 +1,80 @@
+/* Integer reductions. */
+
+#define vl 32
+
+int
+main(void)
+{
+ const int n = 1000;
+ int i;
+ int result, array[n];
+ int lresult;
+
+ /* '+' reductions. */
+#pragma acc parallel vector_length (vl)
+#pragma acc loop reduction (+:result)
+ for (i = 0; i < n; i++)
+ result += array[i];
+#pragma acc end parallel
+
+ /* '*' reductions. */
+#pragma acc parallel vector_length (vl)
+#pragma acc loop reduction (*:result)
+ for (i = 0; i < n; i++)
+ result *= array[i];
+#pragma acc end parallel
+
+// result = 0;
+// vresult = 0;
+//
+// /* 'max' reductions. */
+// #pragma acc parallel vector_length (vl)
+// #pragma acc loop reduction (+:result)
+// for (i = 0; i < n; i++)
+// result = result > array[i] ? result : array[i];
+// #pragma acc end parallel
+//
+// /* 'min' reductions. */
+// #pragma acc parallel vector_length (vl)
+// #pragma acc loop reduction (+:result)
+// for (i = 0; i < n; i++)
+// result = result < array[i] ? result : array[i];
+// #pragma acc end parallel
+
+ /* '&' reductions. */
+#pragma acc parallel vector_length (vl)
+#pragma acc loop reduction (&:result)
+ for (i = 0; i < n; i++)
+ result &= array[i];
+#pragma acc end parallel
+
+ /* '|' reductions. */
+#pragma acc parallel vector_length (vl)
+#pragma acc loop reduction (|:result)
+ for (i = 0; i < n; i++)
+ result |= array[i];
+#pragma acc end parallel
+
+ /* '^' reductions. */
+#pragma acc parallel vector_length (vl)
+#pragma acc loop reduction (^:result)
+ for (i = 0; i < n; i++)
+ result ^= array[i];
+#pragma acc end parallel
+
+ /* '&&' reductions. */
+#pragma acc parallel vector_length (vl)
+#pragma acc loop reduction (&&:lresult)
+ for (i = 0; i < n; i++)
+ lresult = lresult && (result > array[i]);
+#pragma acc end parallel
+
+ /* '||' reductions. */
+#pragma acc parallel vector_length (vl)
+#pragma acc loop reduction (||:lresult)
+ for (i = 0; i < n; i++)
+ lresult = lresult || (result > array[i]);
+#pragma acc end parallel
+
+ return 0;
+}
diff --git a/gcc/testsuite/c-c++-common/goacc/reduction-2.c b/gcc/testsuite/c-c++-common/goacc/reduction-2.c
new file mode 100644
index 0000000..9686b37
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/goacc/reduction-2.c
@@ -0,0 +1,56 @@
+/* float reductions. */
+
+#define vl 32
+
+int
+main(void)
+{
+ const int n = 1000;
+ int i;
+ float result, array[n];
+ int lresult;
+
+ /* '+' reductions. */
+#pragma acc parallel vector_length (vl)
+#pragma acc loop reduction (+:result)
+ for (i = 0; i < n; i++)
+ result += array[i];
+#pragma acc end parallel
+
+ /* '*' reductions. */
+#pragma acc parallel vector_length (vl)
+#pragma acc loop reduction (*:result)
+ for (i = 0; i < n; i++)
+ result *= array[i];
+#pragma acc end parallel
+
+// /* 'max' reductions. */
+// #pragma acc parallel vector_length (vl)
+// #pragma acc loop reduction (+:result)
+// for (i = 0; i < n; i++)
+// result = result > array[i] ? result : array[i];
+// #pragma acc end parallel
+//
+// /* 'min' reductions. */
+// #pragma acc parallel vector_length (vl)
+// #pragma acc loop reduction (+:result)
+// for (i = 0; i < n; i++)
+// result = result < array[i] ? result : array[i];
+// #pragma acc end parallel
+
+ /* '&&' reductions. */
+#pragma acc parallel vector_length (vl)
+#pragma acc loop reduction (&&:lresult)
+ for (i = 0; i < n; i++)
+ lresult = lresult && (result > array[i]);
+#pragma acc end parallel
+
+ /* '||' reductions. */
+#pragma acc parallel vector_length (vl)
+#pragma acc loop reduction (||:lresult)
+ for (i = 0; i < n; i++)
+ lresult = lresult || (result > array[i]);
+#pragma acc end parallel
+
+ return 0;
+}
diff --git a/gcc/testsuite/c-c++-common/goacc/reduction-3.c b/gcc/testsuite/c-c++-common/goacc/reduction-3.c
new file mode 100644
index 0000000..c618c4e
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/goacc/reduction-3.c
@@ -0,0 +1,56 @@
+/* double reductions. */
+
+#define vl 32
+
+int
+main(void)
+{
+ const int n = 1000;
+ int i;
+ double result, array[n];
+ int lresult;
+
+ /* '+' reductions. */
+#pragma acc parallel vector_length (vl)
+#pragma acc loop reduction (+:result)
+ for (i = 0; i < n; i++)
+ result += array[i];
+#pragma acc end parallel
+
+ /* '*' reductions. */
+#pragma acc parallel vector_length (vl)
+#pragma acc loop reduction (*:result)
+ for (i = 0; i < n; i++)
+ result *= array[i];
+#pragma acc end parallel
+
+// /* 'max' reductions. */
+// #pragma acc parallel vector_length (vl)
+// #pragma acc loop reduction (+:result)
+// for (i = 0; i < n; i++)
+// result = result > array[i] ? result : array[i];
+// #pragma acc end parallel
+//
+// /* 'min' reductions. */
+// #pragma acc parallel vector_length (vl)
+// #pragma acc loop reduction (+:result)
+// for (i = 0; i < n; i++)
+// result = result < array[i] ? result : array[i];
+// #pragma acc end parallel
+
+ /* '&&' reductions. */
+#pragma acc parallel vector_length (vl)
+#pragma acc loop reduction (&&:lresult)
+ for (i = 0; i < n; i++)
+ lresult = lresult && (result > array[i]);
+#pragma acc end parallel
+
+ /* '||' reductions. */
+#pragma acc parallel vector_length (vl)
+#pragma acc loop reduction (||:lresult)
+ for (i = 0; i < n; i++)
+ lresult = lresult || (result > array[i]);
+#pragma acc end parallel
+
+ return 0;
+}
diff --git a/gcc/testsuite/c-c++-common/goacc/reduction-4.c b/gcc/testsuite/c-c++-common/goacc/reduction-4.c
new file mode 100644
index 0000000..1e032a1
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/goacc/reduction-4.c
@@ -0,0 +1,58 @@
+/* complex reductions. */
+
+#define vl 32
+
+int
+main(void)
+{
+ const int n = 1000;
+ int i;
+ __complex__ double result, array[n];
+ int lresult;
+
+ /* '+' reductions. */
+#pragma acc parallel vector_length (vl)
+#pragma acc loop reduction (+:result)
+ for (i = 0; i < n; i++)
+ result += array[i];
+#pragma acc end parallel
+
+ /* Needs support for complex multiplication. */
+
+// /* '*' reductions. */
+// #pragma acc parallel vector_length (vl)
+// #pragma acc loop reduction (*:result)
+// for (i = 0; i < n; i++)
+// result *= array[i];
+// #pragma acc end parallel
+//
+// /* 'max' reductions. */
+// #pragma acc parallel vector_length (vl)
+// #pragma acc loop reduction (+:result)
+// for (i = 0; i < n; i++)
+// result = result > array[i] ? result : array[i];
+// #pragma acc end parallel
+//
+// /* 'min' reductions. */
+// #pragma acc parallel vector_length (vl)
+// #pragma acc loop reduction (+:result)
+// for (i = 0; i < n; i++)
+// result = result < array[i] ? result : array[i];
+// #pragma acc end parallel
+
+ /* '&&' reductions. */
+#pragma acc parallel vector_length (vl)
+#pragma acc loop reduction (&&:lresult)
+ for (i = 0; i < n; i++)
+ lresult = lresult && (__real__(result) > __real__(array[i]));
+#pragma acc end parallel
+
+ /* '||' reductions. */
+#pragma acc parallel vector_length (vl)
+#pragma acc loop reduction (||:lresult)
+ for (i = 0; i < n; i++)
+ lresult = lresult || (__real__(result) > __real__(array[i]));
+#pragma acc end parallel
+
+ return 0;
+}