re PR tree-optimization/81354 (Segmentation fault in SSA Strength Reduction using...

[gcc]

2017-08-08  Bill Schmidt  <wschmidt@linux.vnet.ibm.com>

	PR tree-optimization/81354
	* gimple-ssa-strength-reduction.c (create_add_on_incoming_edge):
	Insert on edges rather than explicitly creating landing pads.
	(analyze_candidates_and_replace): Commit edge inserts.

[gcc/testsuite]

2017-08-08  Bill Schmidt  <wschmidt@linux.vnet.ibm.com>

	PR tree-optimization/81354
	* g++.dg/torture/pr81354.C: New file.

From-SVN: r250955

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index b0a59d55164ee26c96a3ef25c9456398a2ee3615..6051e8f50689c088f536522db707514e8ef7425f 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2017-08-08  Bill Schmidt  <wschmidt@linux.vnet.ibm.com>
+
+       PR tree-optimization/81354
+       * g++.dg/torture/pr81354.C: New file.
+
 2017-08-08  Richard Biener  <rguenther@suse.de>
 
        PR middle-end/81719

diff --git a/gcc/gimple-ssa-strength-reduction.c b/gcc/gimple-ssa-strength-reduction.c
index 00c304447002321e6d399003a933f2a953e80ba1..780e07914f6a971c5e02fd705100d356ae2a8ff4 100644 (file)
--- a/gcc/gimple-ssa-strength-reduction.c
+++ b/gcc/gimple-ssa-strength-reduction.c
@@ -2224,8 +2224,6 @@ create_add_on_incoming_edge (slsr_cand_t c, tree basis_name,
                             widest_int increment, edge e, location_t loc,
                             bool known_stride)
 {
-  basic_block insert_bb;
-  gimple_stmt_iterator gsi;
   tree lhs, basis_type;
   gassign *new_stmt, *cast_stmt = NULL;
 
@@ -2294,39 +2292,25 @@ create_add_on_incoming_edge (slsr_cand_t c, tree basis_name,
       }
     }
 
-  insert_bb = single_succ_p (e->src) ? e->src : split_edge (e);
-  gsi = gsi_last_bb (insert_bb);
-
-  if (!gsi_end_p (gsi) && stmt_ends_bb_p (gsi_stmt (gsi)))
+  if (cast_stmt)
     {
-      gsi_insert_before (&gsi, new_stmt, GSI_SAME_STMT);
-      if (cast_stmt)
-       {
-         gsi_insert_before (&gsi, cast_stmt, GSI_SAME_STMT);
-         gimple_set_location (cast_stmt, loc);
-       }
-    }
-  else
-    {
-      if (cast_stmt)
-       {
-         gsi_insert_after (&gsi, cast_stmt, GSI_NEW_STMT);
-         gimple_set_location (cast_stmt, loc);
-       }
-      gsi_insert_after (&gsi, new_stmt, GSI_NEW_STMT);
+      gimple_set_location (cast_stmt, loc);
+      gsi_insert_on_edge (e, cast_stmt);
     }
 
   gimple_set_location (new_stmt, loc);
+  gsi_insert_on_edge (e, new_stmt);
 
   if (dump_file && (dump_flags & TDF_DETAILS))
     {
       if (cast_stmt)
        {
-         fprintf (dump_file, "Inserting cast in block %d: ",
-                  insert_bb->index);
+         fprintf (dump_file, "Inserting cast on edge %d->%d: ",
+                  e->src->index, e->dest->index);
          print_gimple_stmt (dump_file, cast_stmt, 0);
        }
-      fprintf (dump_file, "Inserting in block %d: ", insert_bb->index);
+      fprintf (dump_file, "Inserting on edge %d->%d: ", e->src->index,
+              e->dest->index);
       print_gimple_stmt (dump_file, new_stmt, 0);
     }
 
@@ -3770,6 +3754,10 @@ analyze_candidates_and_replace (void)
          free (incr_vec);
        }
     }
+
+  /* For conditional candidates, we may have uncommitted insertions
+     on edges to clean up.  */
+  gsi_commit_edge_inserts ();
 }
 
 namespace {

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 1fec0ec1152c3178358d9550c5040051cef5e423..e2d081d8e267009e75e8b0a34cf2e4a7cb4af4bf 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2017-08-08  Bill Schmidt  <wschmidt@linux.vnet.ibm.com>
+
+       PR tree-optimization/81354
+       * g++.dg/torture/pr81354.C: New file.
+
 2017-08-08  Richard Biener  <rguenther@suse.de>
 
        PR middle-end/81719

diff --git a/gcc/testsuite/g++.dg/torture/pr81354.C b/gcc/testsuite/g++.dg/torture/pr81354.C
new file mode 100644 (file)
index 0000000..b3ba8f0
--- /dev/null
+++ b/gcc/testsuite/g++.dg/torture/pr81354.C
@@ -0,0 +1,24 @@
+// PR81354 reported this test as crashing in a limited range of revisions.
+// { dg-do compile }
+
+struct T { double a; double b; };
+
+void foo(T Ad[], int As[2])
+{
+  int j;
+  int i;
+  int Bs[2] = {0,0};
+  T Bd[16];
+
+  for (j = 0; j < 4; j++) {
+    for (i = 0; i + 1 <= j + 1; i++) {
+      Ad[i + As[0] * j] = Bd[i + Bs[0] * j];
+    }
+
+    i = j + 1;  // <- comment out this line and it does not crash
+    for (; i + 1 < 5; i++) {
+      Ad[i + As[0] * j].a = 0.0;
+      Ad[i + As[0] * j].b = 0.0;
+    }
+  }
+}