re PR middle-end/80764 (ICE at -O3 in both 32-bit and 64-bit modes on…

re PR middle-end/80764 (ICE at -O3 in both 32-bit and 64-bit modes on x86_64-linux-gnu (internal compiler error: in verify_loop_structure, at cfgloop.c:1644))

2017-05-19  Richard Biener  <rguenther@suse.de>

	PR middle-end/80764
	* cfgexpand.c (expand_gimple_cond): Fix loop fixup.

	* gcc.dg/torture/pr80764.c: New testcase.

From-SVN: r248261

gcc/ChangeLog

+2017-05-19  Richard Biener  <rguenther@suse.de>
+
+	PR middle-end/80764
+	* cfgexpand.c (expand_gimple_cond): Fix loop fixup.
+
 2017-05-18  Segher Boessenkool  <segher@kernel.crashing.org>
 
 	* config/rs6000/rs6000.c (struct machine_function): Add field

gcc/cfgexpand.c

@@ -2503,7 +2503,10 @@ expand_gimple_cond (basic_block bb, gcond *stmt)
   false_edge->flags |= EDGE_FALLTHRU;
   new_bb->count = false_edge->count;
   new_bb->frequency = EDGE_FREQUENCY (false_edge);
-  add_bb_to_loop (new_bb, bb->loop_father);
+  add_bb_to_loop (new_bb, dest->loop_father);
+  if (bb->loop_father->latch == bb
+      && bb->loop_father->header == dest)
+    bb->loop_father->latch = new_bb;
   new_edge = make_edge (new_bb, dest, 0);
   new_edge->probability = REG_BR_PROB_BASE;
   new_edge->count = new_bb->count;

gcc/testsuite/ChangeLog

+2017-05-19  Richard Biener  <rguenther@suse.de>
+
+	PR middle-end/80764
+	* gcc.dg/torture/pr80764.c: New testcase.
+
 2017-05-18  Michael Meissner  <meissner@linux.vnet.ibm.com>
 
 	PR target/80510

gcc/testsuite/gcc.dg/torture/pr80764.c

+/* { dg-do compile } */
+
+int b, d, f, h;
+char e;
+int fn1();
+int main() { return fn1(); }
+int fn1(int p1) {
+    for (; d;)
+      for (; e < 3;) {
+	  for (; h;)
+	    b = fn1(0);
+	  return f;
+      }
+}