0001-Handle-double-reduction-in-parloops.patch
Handle double reduction in parloops
2015-07-13 Tom de Vries<t...@codesourcery.com>
PR tree-optimization/66851
* tree-parloops.c (reduc_stmt_res): New function.
(initialize_reductions, add_field_for_reduction)
(create_phi_for_local_result, create_loads_for_reductions)
(create_stores_for_reduction, build_new_reduction): Handle case that
reduc_stmt is a phi.
(gather_scalar_reductions): Allow double_reduc reductions.
* gcc.dg/autopar/outer-4.c (parloop): Remove superfluous noinline
attribute. Remove xfail on scan for parallelizing outer loop.
(main): Remove.
* testsuite/libgomp.c/outer-4.c: New test.
---
gcc/testsuite/gcc.dg/autopar/outer-4.c | 17 ++++------------
gcc/tree-parloops.c | 37 +++++++++++++++++++++++++---------
libgomp/testsuite/libgomp.c/outer-4.c | 36 +++++++++++++++++++++++++++++++++
3 files changed, 68 insertions(+), 22 deletions(-)
create mode 100644 libgomp/testsuite/libgomp.c/outer-4.c
diff --git a/gcc/testsuite/gcc.dg/autopar/outer-4.c
b/gcc/testsuite/gcc.dg/autopar/outer-4.c
index 6fd37c5..f435080 100644
--- a/gcc/testsuite/gcc.dg/autopar/outer-4.c
+++ b/gcc/testsuite/gcc.dg/autopar/outer-4.c
@@ -6,15 +6,13 @@ void abort (void);
int g_sum=0;
int x[500][500];
-__attribute__((noinline))
-void parloop (int N)
+void
+parloop (int N)
{
int i, j;
int sum;
- /* Double reduction is currently not supported, outer loop is not
- parallelized. Inner reduction is detected, inner loop is
- parallelized. */
+ /* Double reduction is detected, outer loop is parallelized. */
sum = 0;
for (i = 0; i < N; i++)
for (j = 0; j < N; j++)
@@ -23,13 +21,6 @@ void parloop (int N)
g_sum = sum;
}
-int main(void)
-{
- parloop(500);
-
- return 0;
-}
-
-/* { dg-final { scan-tree-dump-times "parallelizing outer loop" 1 "parloops" {
xfail *-*-* } } } */
+/* { dg-final { scan-tree-dump-times "parallelizing outer loop" 1 "parloops" }
} */
/* { dg-final { scan-tree-dump-times "loopfn" 4 "optimized" } } */
diff --git a/gcc/tree-parloops.c b/gcc/tree-parloops.c
index 21ed17b..db7da62 100644
--- a/gcc/tree-parloops.c
+++ b/gcc/tree-parloops.c
@@ -560,6 +560,14 @@ take_address_of (tree obj, tree type, edge entry,
return name;
}
+static tree
+reduc_stmt_res (gimple stmt)
+{
+ return (gimple_code (stmt) == GIMPLE_PHI
+ ? gimple_phi_result (stmt)
+ : gimple_assign_lhs (stmt));
+}
+
/* Callback for htab_traverse. Create the initialization statement
for reduction described in SLOT, and place it at the preheader of
the loop described in DATA. */
@@ -586,7 +594,7 @@ initialize_reductions (reduction_info **slot, struct loop
*loop)
c = build_omp_clause (gimple_location (reduc->reduc_stmt),
OMP_CLAUSE_REDUCTION);
OMP_CLAUSE_REDUCTION_CODE (c) = reduc->reduction_code;
- OMP_CLAUSE_DECL (c) = SSA_NAME_VAR (gimple_assign_lhs (reduc->reduc_stmt));
+ OMP_CLAUSE_DECL (c) = SSA_NAME_VAR (reduc_stmt_res (reduc->reduc_stmt));
init = omp_reduction_init (c, TREE_TYPE (bvar));
reduc->init = init;
@@ -993,7 +1001,7 @@ add_field_for_reduction (reduction_info **slot, tree type)
{
struct reduction_info *const red = *slot;
- tree var = gimple_assign_lhs (red->reduc_stmt);
+ tree var = reduc_stmt_res (red->reduc_stmt);
tree field = build_decl (gimple_location (red->reduc_stmt), FIELD_DECL,
SSA_NAME_IDENTIFIER (var), TREE_TYPE (var));
@@ -1053,12 +1061,12 @@ create_phi_for_local_result (reduction_info **slot,
struct loop *loop)
e = EDGE_PRED (store_bb, 1);
else
e = EDGE_PRED (store_bb, 0);
- local_res = copy_ssa_name (gimple_assign_lhs (reduc->reduc_stmt));
+ tree lhs = reduc_stmt_res (reduc->reduc_stmt);
+ local_res = copy_ssa_name (lhs);
locus = gimple_location (reduc->reduc_stmt);
new_phi = create_phi_node (local_res, store_bb);
add_phi_arg (new_phi, reduc->init, e, locus);
- add_phi_arg (new_phi, gimple_assign_lhs (reduc->reduc_stmt),
- FALLTHRU_EDGE (loop->latch), locus);
+ add_phi_arg (new_phi, lhs, FALLTHRU_EDGE (loop->latch), locus);
reduc->new_phi = new_phi;
return 1;
@@ -1151,7 +1159,7 @@ create_loads_for_reductions (reduction_info **slot,
struct clsn_data *clsn_data)
struct reduction_info *const red = *slot;
gimple stmt;
gimple_stmt_iterator gsi;
- tree type = TREE_TYPE (gimple_assign_lhs (red->reduc_stmt));
+ tree type = TREE_TYPE (reduc_stmt_res (red->reduc_stmt));
tree load_struct;
tree name;
tree x;
@@ -1212,7 +1220,7 @@ create_stores_for_reduction (reduction_info **slot,
struct clsn_data *clsn_data)
tree t;
gimple stmt;
gimple_stmt_iterator gsi;
- tree type = TREE_TYPE (gimple_assign_lhs (red->reduc_stmt));
+ tree type = TREE_TYPE (reduc_stmt_res (red->reduc_stmt));
gsi = gsi_last_bb (clsn_data->store_bb);
t = build3 (COMPONENT_REF, type, clsn_data->store, red->field, NULL_TREE);
@@ -2321,6 +2329,7 @@ build_new_reduction (reduction_info_table_type
*reduction_list,
{
reduction_info **slot;
struct reduction_info *new_reduction;
+ enum tree_code reduction_code;
gcc_assert (reduc_stmt);
@@ -2332,12 +2341,22 @@ build_new_reduction (reduction_info_table_type
*reduction_list,
fprintf (dump_file, "\n");
}
+ if (gimple_code (reduc_stmt) == GIMPLE_PHI)
+ {
+ tree op1 = PHI_ARG_DEF (reduc_stmt, 0);
+ gimple def1 = SSA_NAME_DEF_STMT (op1);
+ reduction_code = gimple_assign_rhs_code (def1);
+ }
+
+ else
+ reduction_code = gimple_assign_rhs_code (reduc_stmt);
+
new_reduction = XCNEW (struct reduction_info);
new_reduction->reduc_stmt = reduc_stmt;
new_reduction->reduc_phi = phi;
new_reduction->reduc_version = SSA_NAME_VERSION (gimple_phi_result (phi));
- new_reduction->reduction_code = gimple_assign_rhs_code (reduc_stmt);
+ new_reduction->reduction_code = reduction_code;
slot = reduction_list->find_slot (new_reduction, INSERT);
*slot = new_reduction;
}
@@ -2378,7 +2397,7 @@ gather_scalar_reductions (loop_p loop,
reduction_info_table_type *reduction_list
gimple reduc_stmt = vect_force_simple_reduction (simple_loop_info,
phi, true,
&double_reduc);
- if (reduc_stmt && !double_reduc)
+ if (reduc_stmt)
build_new_reduction (reduction_list, reduc_stmt, phi);
}
}
diff --git a/libgomp/testsuite/libgomp.c/outer-4.c
b/libgomp/testsuite/libgomp.c/outer-4.c
new file mode 100644
index 0000000..f77f634
--- /dev/null
+++ b/libgomp/testsuite/libgomp.c/outer-4.c
@@ -0,0 +1,36 @@
+/* { dg-do run } */
+/* { dg-additional-options "-ftree-parallelize-loops=2" } */
+
+void abort (void);
+
+int g_sum = 1;
+
+int x[500][500];
+
+void __attribute__((noinline,noclone))
+parloop (int N)
+{
+ int i, j;
+ int sum;
+
+ /* Double reduction is detected, outer loop is parallelized. */
+ sum = 0;
+ for (i = 0; i < N; i++)
+ for (j = 0; j < N; j++)
+ sum += x[i][j];
+
+ g_sum = sum;
+}
+
+int
+main (void)
+{
+ x[234][432] = 2;
+
+ parloop (500);
+
+ if (g_sum != 2)
+ abort ();
+
+ return 0;
+}
-- 1.9.1
