re PR tree-optimization/87328 (ICE in do_rpo_vn, at tree-ssa-sccvn.c:6566)

2018-09-17  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/87328
	* tree-ssa-sccvn.c (process_bb): Remove assertion about not
	visiting unexecutable backedges when not iterating.
	(do_rpo_vn): Mark all edges not executable even when not
	iterating.

	* gcc.dg/torture/pr87328.c: New testcase.

From-SVN: r264369

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index f653d66..585056e 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@
+2018-09-17  Richard Biener  <rguenther@suse.de>
+
+       PR tree-optimization/87328
+       * tree-ssa-sccvn.c (process_bb): Remove assertion about not
+       visiting unexecutable backedges when not iterating.
+       (do_rpo_vn): Mark all edges not executable even when not
+       iterating.
+
 2018-09-17  Martin Jambor  <mjambor@suse.cz>
 
        PR c/63886

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 4fd1ff9..5cce863 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2018-09-17  Richard Biener  <rguenther@suse.de>
+
+       PR tree-optimization/87328
+       * gcc.dg/torture/pr87328.c: New testcase.
+
 2018-09-17  Martin Jambor  <mjambor@suse.cz>
 
        PR c/63886

diff --git a/gcc/testsuite/gcc.dg/torture/pr87328.c b/gcc/testsuite/gcc.dg/torture/pr87328.c
new file mode 100644 (file)
index 0000000..50e1cdf
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr87328.c
@@ -0,0 +1,25 @@
+/* { dg-do compile } */
+/* { dg-additional-options "-fno-tree-ccp -fno-tree-forwprop" } */
+
+void
+tp (void)
+{
+  int qt;
+
+  qt = 0;
+  if (qt != 0)
+    {
+      if (0)
+       {
+h5:
+         qt = 0;
+         while (qt < 1)
+           {
+           }
+       }
+
+      ++qt;
+    }
+
+  goto h5;
+}

diff --git a/gcc/tree-ssa-sccvn.c b/gcc/tree-ssa-sccvn.c
index a9e4d34..a49e7f6 100644 (file)
--- a/gcc/tree-ssa-sccvn.c
+++ b/gcc/tree-ssa-sccvn.c
@@ -5978,7 +5978,6 @@ process_bb (rpo_elim &avail, basic_block bb,
                fprintf (dump_file,
                         "marking outgoing edge %d -> %d executable\n",
                         e->src->index, e->dest->index);
-             gcc_checking_assert (iterate || !(e->flags & EDGE_DFS_BACK));
              e->flags |= EDGE_EXECUTABLE;
              e->dest->flags |= BB_EXECUTABLE;
            }
@@ -6125,7 +6124,6 @@ process_bb (rpo_elim &avail, basic_block bb,
                         "marking known outgoing %sedge %d -> %d executable\n",
                         e->flags & EDGE_DFS_BACK ? "back-" : "",
                         e->src->index, e->dest->index);
-             gcc_checking_assert (iterate || !(e->flags & EDGE_DFS_BACK));
              e->flags |= EDGE_EXECUTABLE;
              e->dest->flags |= BB_EXECUTABLE;
            }
@@ -6148,7 +6146,6 @@ process_bb (rpo_elim &avail, basic_block bb,
                    fprintf (dump_file,
                             "marking outgoing edge %d -> %d executable\n",
                             e->src->index, e->dest->index);
-                 gcc_checking_assert (iterate || !(e->flags & EDGE_DFS_BACK));
                  e->flags |= EDGE_EXECUTABLE;
                  e->dest->flags |= BB_EXECUTABLE;
                }
@@ -6390,10 +6387,7 @@ do_rpo_vn (function *fn, edge entry, bitmap exit_bbs,
        {
          if (e->flags & EDGE_DFS_BACK)
            has_backedges = true;
-         if (! iterate && (e->flags & EDGE_DFS_BACK))
-           e->flags |= EDGE_EXECUTABLE;
-         else
-           e->flags &= ~EDGE_EXECUTABLE;
+         e->flags &= ~EDGE_EXECUTABLE;
          if (e == entry)
            continue;
          if (bb_to_rpo[e->src->index] > i)