re PR tree-optimization/87266 (ICE: Segmentation fault (in useless_type_conversion_p, tree_nop_conversion_p, or is_gimple_reg_type))

2018-09-12  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/87266
	* tree-ssa-sccvn.c (do_rpo_vn): Always iterate to not yet
	visited blocks.

	* gcc.dg/torture/pr87266-1.c: New testcase.
	* gcc.dg/torture/pr87266-2.c: Likewise.
	* gcc.dg/torture/pr87266-3.c: Likewise.
	* gcc.dg/torture/pr87266-4.c: Likewise.

From-SVN: r264237

7 files changed, 159 insertions, 1 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 77ef4bb..c96b5eb 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2018-09-12  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/87266
+	* tree-ssa-sccvn.c (do_rpo_vn): Always iterate to not yet
+	visited blocks.
+
 2018-09-12  Andreas Krebbel  <krebbel@linux.ibm.com>
 
 	* config/s390/s390.md (PFPO_RND_MODE_DFP, PFPO_RND_MODE_BFP): New
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index a29d014..5f73cd8 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,11 @@
+2018-09-12  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/87266
+	* gcc.dg/torture/pr87266-1.c: New testcase.
+	* gcc.dg/torture/pr87266-2.c: Likewise.
+	* gcc.dg/torture/pr87266-3.c: Likewise.
+	* gcc.dg/torture/pr87266-4.c: Likewise.
+
 2018-09-12  Andreas Krebbel  <krebbel@linux.ibm.com>
 
 	* gcc.target/s390/dfp_to_bfp_rounding.c: New test.
diff --git a/gcc/testsuite/gcc.dg/torture/pr87266-1.c b/gcc/testsuite/gcc.dg/torture/pr87266-1.c
new file mode 100644
index 0000000..dc0a4a1
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr87266-1.c
@@ -0,0 +1,32 @@
+/* { dg-do compile } */
+/* { dg-additional-options "-fno-tree-ccp -fno-tree-forwprop" } */
+
+void
+iw (int gu, int mq, int r2)
+{
+  int yn = 0;
+
+  while (gu < 1)
+    {
+      for (;;)
+        ;
+
+ bb:;
+      int ay = 0;
+
+      while (ay < 1)
+        ++mq;
+    }
+
+  if (yn != 0)
+    goto up;
+
+  if (0)
+    {
+ up:
+      if (r2 == 0)
+        goto bb;
+    }
+
+  goto up;
+}
diff --git a/gcc/testsuite/gcc.dg/torture/pr87266-2.c b/gcc/testsuite/gcc.dg/torture/pr87266-2.c
new file mode 100644
index 0000000..cf0254f
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr87266-2.c
@@ -0,0 +1,32 @@
+/* { dg-do compile } */
+/* { dg-additional-options "-fno-tree-ccp -fno-tree-forwprop" } */
+
+void
+iw (int gu, int mq, int r2)
+{
+  int yn = 0;
+
+  while (gu < 1)
+    {
+      for (;;)
+        ;
+
+ bb:;
+      int ay = 0;
+
+      while (yn < 1)
+        ++mq;
+    }
+
+  if (yn != 0)
+    goto up;
+
+  if (0)
+    {
+ up:
+      if (r2 == 0)
+        goto bb;
+    }
+
+  goto up;
+}
diff --git a/gcc/testsuite/gcc.dg/torture/pr87266-3.c b/gcc/testsuite/gcc.dg/torture/pr87266-3.c
new file mode 100644
index 0000000..0f3f3ba
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr87266-3.c
@@ -0,0 +1,32 @@
+/* { dg-do compile } */
+/* { dg-additional-options "-fno-tree-ccp -fno-tree-forwprop" } */
+
+void
+iw (int gu, int mq, int r2)
+{
+  int yn = 0;
+
+  while (gu < 1)
+    {
+      int ay = 0;
+
+      for (;;)
+        ;
+
+ bb:
+      while (ay < 1)
+        ++mq;
+    }
+
+  if (yn != 0)
+    goto up;
+
+  if (0)
+    {
+ up:
+      if (r2 == 0)
+        goto bb;
+    }
+
+  goto up;
+}
diff --git a/gcc/testsuite/gcc.dg/torture/pr87266-4.c b/gcc/testsuite/gcc.dg/torture/pr87266-4.c
new file mode 100644
index 0000000..e8d5ff1
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr87266-4.c
@@ -0,0 +1,38 @@
+/* { dg-do compile } */
+/* { dg-additional-options "-fno-tree-dominator-opts -fno-tree-forwprop" } */
+
+unsigned long int
+re (long int j9)
+{
+  if (j9 == 0)
+    return 1;
+
+  return j9;
+}
+
+void
+zq (int bt, int yy)
+{
+  int p3 = 0, go = 4, ez = go;
+
+  while (go != 0)
+    {
+      if (ez + !!bt - re (bt) != 0 && go != 0)
+	{
+	  if (yy != 0)
+	    p3 = yy;
+	}
+      else
+	return;
+
+      go = 2;
+    }
+}
+
+void
+my (unsigned long int n6, int bt, int yy)
+{
+  zq (bt, yy);
+  n6 = n6 == bt;
+  zq (bt, yy);
+}
diff --git a/gcc/tree-ssa-sccvn.c b/gcc/tree-ssa-sccvn.c
index 6fec624..8bf724e 100644
--- a/gcc/tree-ssa-sccvn.c
+++ b/gcc/tree-ssa-sccvn.c
@@ -6471,6 +6471,17 @@ do_rpo_vn (function *fn, edge entry, bitmap exit_bbs,
 		== (EDGE_DFS_BACK|EDGE_EXECUTABLE)
 		&& rpo_state[bb_to_rpo[e->dest->index]].iterate)
 	      {
+		int destidx = bb_to_rpo[e->dest->index];
+		if (!rpo_state[destidx].visited)
+		  {
+		    if (dump_file && (dump_flags & TDF_DETAILS))
+		      fprintf (dump_file, "Unvisited destination %d\n",
+			       e->dest->index);
+		    if (iterate_to == -1
+			|| destidx < iterate_to)
+		      iterate_to = destidx;
+		    continue;
+		  }
 		if (dump_file && (dump_flags & TDF_DETAILS))
 		  fprintf (dump_file, "Looking for changed values of backedge "
 			   "%d->%d destination PHIs\n",
@@ -6497,7 +6508,6 @@ do_rpo_vn (function *fn, edge entry, bitmap exit_bbs,
 			    && dump_file && (dump_flags & TDF_DETAILS))
 			  fprintf (dump_file, "PHI was CSEd and hashtable "
 				   "state (changed)\n");
-			int destidx = bb_to_rpo[e->dest->index];
 			if (iterate_to == -1
 			    || destidx < iterate_to)
 			  iterate_to = destidx;