Handle 2 preds for fin_bb in expand_omp_for_static_chunk

2015-09-03  Tom de Vries  <tom@codesourcery.com>

	PR tree-optimization/65637
	* omp-low.c (expand_omp_for_static_chunk): Handle case that fin_bb has 2
	predecessors.

	* gcc.dg/autopar/reduc-4.c: New test.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@227438 138bc75d-0d04-0410-961f-82ee72b054a4

4 files changed, 32 insertions, 9 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index f09f24f6e95..33fc52371d5 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,6 +1,12 @@
 2015-09-03  Tom de Vries  <tom@codesourcery.com>
 
 	PR tree-optimization/65637
+	* omp-low.c (expand_omp_for_static_chunk): Handle case that fin_bb has 2
+	predecessors.
+
+2015-09-03  Tom de Vries  <tom@codesourcery.com>
+
+	PR tree-optimization/65637
 	* omp-low.c (find_phi_with_arg_on_edge): New function.
 	(expand_omp_for_static_chunk): Fix inner loop phi.
 
diff --git a/gcc/omp-low.c b/gcc/omp-low.c
index 22e55f6c3cf..88a5149250b 100644
--- a/gcc/omp-low.c
+++ b/gcc/omp-low.c
@@ -7035,7 +7035,7 @@ expand_omp_for_static_chunk (struct omp_region *region,
       se->probability = REG_BR_PROB_BASE / 2000 - 1;
       if (gimple_in_ssa_p (cfun))
 	{
-	  int dest_idx = find_edge (entry_bb, fin_bb)->dest_idx;
+	  int dest_idx = find_edge (iter_part_bb, fin_bb)->dest_idx;
 	  for (gphi_iterator gpi = gsi_start_phis (fin_bb);
 	       !gsi_end_p (gpi); gsi_next (&gpi))
 	    {
@@ -7316,7 +7316,7 @@ expand_omp_for_static_chunk (struct omp_region *region,
       /* When we redirect the edge from trip_update_bb to iter_part_bb, we
 	 remove arguments of the phi nodes in fin_bb.  We need to create
 	 appropriate phi nodes in iter_part_bb instead.  */
-      se = single_pred_edge (fin_bb);
+      se = find_edge (iter_part_bb, fin_bb);
       re = single_succ_edge (trip_update_bb);
       vec<edge_var_map> *head = redirect_edge_var_map_vector (re);
       ene = single_succ_edge (entry_bb);
@@ -7331,6 +7331,10 @@ expand_omp_for_static_chunk (struct omp_region *region,
 	  phi = psi.phi ();
 	  t = gimple_phi_result (phi);
 	  gcc_assert (t == redirect_edge_var_map_result (vm));
+
+	  if (!single_pred_p (fin_bb))
+	    t = copy_ssa_name (t, phi);
+
 	  nphi = create_phi_node (t, iter_part_bb);
 
 	  t = PHI_ARG_DEF_FROM_EDGE (phi, se);
@@ -7355,16 +7359,20 @@ expand_omp_for_static_chunk (struct omp_region *region,
 	  gcc_assert (inner_loop_phi != NULL);
 	  add_phi_arg (inner_loop_phi, gimple_phi_result (nphi),
 		       find_edge (seq_start_bb, body_bb), locus);
+
+	  if (!single_pred_p (fin_bb))
+	    add_phi_arg (phi, gimple_phi_result (nphi), se, locus);
 	}
       gcc_assert (gsi_end_p (psi) && (head == NULL || i == head->length ()));
       redirect_edge_var_map_clear (re);
-      while (1)
-	{
-	  psi = gsi_start_phis (fin_bb);
-	  if (gsi_end_p (psi))
-	    break;
-	  remove_phi_node (&psi, false);
-	}
+      if (single_pred_p (fin_bb))
+	while (1)
+	  {
+	    psi = gsi_start_phis (fin_bb);
+	    if (gsi_end_p (psi))
+	      break;
+	    remove_phi_node (&psi, false);
+	  }
 
       /* Make phi node for trip.  */
       phi = create_phi_node (trip_main, iter_part_bb);
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index bfb7dd2dfb6..191c22b325d 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,6 +1,11 @@
 2015-09-03  Tom de Vries  <tom@codesourcery.com>
 
 	PR tree-optimization/65637
+	* gcc.dg/autopar/reduc-4.c: New test.
+
+2015-09-03  Tom de Vries  <tom@codesourcery.com>
+
+	PR tree-optimization/65637
 	* gcc.dg/autopar/pr46099-2.c: New test.
 
 2015-09-03  Naveen H.S  <Naveen.Hurugalawadi@caviumnetworks.com>
diff --git a/gcc/testsuite/gcc.dg/autopar/reduc-4.c b/gcc/testsuite/gcc.dg/autopar/reduc-4.c
new file mode 100644
index 00000000000..80b15e2852d
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/autopar/reduc-4.c
@@ -0,0 +1,4 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -ftree-parallelize-loops=4 -fdump-tree-parloops-details -fdump-tree-optimized --param parloops-chunk-size=100" } */
+
+#include "reduc-3.c"