re PR rtl-optimization/90026 (ICE: verify_flow_info failed (error: missing barrier after block 2))

	PR rtl-optimization/90026
	* cfgcleanup.c (try_optimize_cfg): When removing empty bb with no
	successors, look for BARRIERs inside of the whole BB_FOOTER chain
	rather than just at the start of it.  If e->src BB_FOOTER is not NULL
	in cfglayout mode, use emit_barrier_after_bb.

	* g++.dg/opt/pr90026.C: New test.

From-SVN: r270304

gcc/ChangeLog

+2019-04-12  Jakub Jelinek  <jakub@redhat.com>
+
+	PR rtl-optimization/90026
+	* cfgcleanup.c (try_optimize_cfg): When removing empty bb with no
+	successors, look for BARRIERs inside of the whole BB_FOOTER chain
+	rather than just at the start of it.  If e->src BB_FOOTER is not NULL
+	in cfglayout mode, use emit_barrier_after_bb.
+
 2018-04-11  Steve Ellcey  <sellcey@marvell.com>
 
 	PR rtl-optimization/87763

gcc/cfgcleanup.c

@@ -2712,23 +2712,23 @@ try_optimize_cfg (int mode)
 
 		      if (current_ir_type () == IR_RTL_CFGLAYOUT)
 			{
-			  if (BB_FOOTER (b)
-			      && BARRIER_P (BB_FOOTER (b)))
+			  rtx_insn *insn;
+			  for (insn = BB_FOOTER (b);
+			       insn; insn = NEXT_INSN (insn))
+			    if (BARRIER_P (insn))
+			      break;
+			  if (insn)
 			    FOR_EACH_EDGE (e, ei, b->preds)
-			      if ((e->flags & EDGE_FALLTHRU)
-				  && BB_FOOTER (e->src) == NULL)
+			      if ((e->flags & EDGE_FALLTHRU))
 				{
-				  if (BB_FOOTER (b))
+				  if (BB_FOOTER (b)
+				      && BB_FOOTER (e->src) == NULL)
 				    {
 				      BB_FOOTER (e->src) = BB_FOOTER (b);
 				      BB_FOOTER (b) = NULL;
 				    }
 				  else
-				    {
-				      start_sequence ();
-				      BB_FOOTER (e->src) = emit_barrier ();
-				      end_sequence ();
-				    }
+				    emit_barrier_after_bb (e->src);
 				}
 			}
 		      else

gcc/testsuite/ChangeLog

+2019-04-12  Jakub Jelinek  <jakub@redhat.com>
+
+	PR rtl-optimization/90026
+	* g++.dg/opt/pr90026.C: New test.
+
 2018-04-11  Steve Ellcey  <sellcey@marvell.com>
 
 	PR rtl-optimization/87763

gcc/testsuite/g++.dg/opt/pr90026.C

+// PR rtl-optimization/90026
+// { dg-do compile }
+// { dg-options "-fnon-call-exceptions -ftracer -O2 -w" }
+
+typedef __SIZE_TYPE__ size_t;
+struct S { int *b; ~S () { delete b; } };
+void bar ();
+char c[sizeof (int)];
+
+void *
+operator new (size_t, void *)
+{
+  __builtin_unreachable ();
+}
+
+void
+foo ()
+{
+  S a;
+  if (a.b)
+    a.b = new int ();
+  bar ();
+  new (c) int ();
+}