From: rguenth <rguenth@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Mon, 17 Sep 2018 13:28:04 +0000 (+0000)
Subject: 2018-09-17  Richard Biener  <rguenther@suse.de>
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=dd7ed3c2c6481b6840919c8a26e0006a5b3e60b3;p=thirdparty%2Fgcc.git

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.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@264369 138bc75d-0d04-0410-961f-82ee72b054a4
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index f653d66f2884..585056e5db83 100644
--- 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 4fd1ff928ab6..5cce863e58af 100644
--- 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
index 000000000000..50e1cdfbb56d
--- /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 a9e4d34e31f6..a49e7f674513 100644
--- 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)