re PR rtl-optimization/83962 (ICE: verify_flow_info failed (too many outgoing…

re PR rtl-optimization/83962 (ICE: verify_flow_info failed (too many outgoing branch edges from bb 8))

       PR rtl-optimization/83962

       * sel-sched-ir.c (tidy_control_flow): Correct the order in which we call
       tidy_fallthru_edge and tidy_control_flow.

       * gcc.dg/pr83962.c: New test.

From-SVN: r259229

gcc/ChangeLog

 2018-04-09  Andrey Belevantsev  <abel@ispras.ru>
 
+	PR rtl-optimization/83962
+
+	* sel-sched-ir.c (tidy_control_flow): Correct the order in which we call
+	tidy_fallthru_edge and tidy_control_flow.
+
+2018-04-09  Andrey Belevantsev  <abel@ispras.ru>
+
 	PR rtl-optimization/83530
 
 	* sel-sched.c (force_next_insn): New global variable.

gcc/sel-sched-ir.c

@@ -3839,9 +3839,13 @@ tidy_control_flow (basic_block xbb, bool full_tidying)
       && INSN_SCHED_TIMES (BB_END (xbb)) == 0
       && !IN_CURRENT_FENCE_P (BB_END (xbb)))
     {
-      if (sel_remove_insn (BB_END (xbb), false, false))
-        return true;
+      /* We used to call sel_remove_insn here that can trigger tidy_control_flow
+         before we fix up the fallthru edge.  Correct that ordering by
+	 explicitly doing the latter before the former.  */
+      clear_expr (INSN_EXPR (BB_END (xbb)));
       tidy_fallthru_edge (EDGE_SUCC (xbb, 0));
+      if (tidy_control_flow (xbb, false))
+	return true;
     }
 
   first = sel_bb_head (xbb);

gcc/testsuite/ChangeLog

 2018-04-09  Andrey Belevantsev  <abel@ispras.ru>
 
+	PR rtl-optimization/83962
+	* gcc.dg/pr83962.c: New test.
+
+2018-04-09  Andrey Belevantsev  <abel@ispras.ru>
+
 	PR rtl-optimization/83530
 	* gcc.dg/pr83530.c: New test.
 

gcc/testsuite/gcc.dg/pr83962.c

+/* { dg-do compile { target powerpc*-*-* ia64-*-* i?86-*-* x86_64-*-* } } */
+/* { dg-options "-std=gnu99 -O1 -fselective-scheduling2 -fschedule-insns2 -fcse-follow-jumps -fno-ssa-phiopt -fno-guess-branch-probability" } */
+unsigned int ca;
+
+void
+v6 (long long unsigned int as, int p9)
+{
+  while (p9 < 1)
+    as = (as != ca) || (as > 1);
+}