re PR middle-end/71619 (ICE: in predict_loops, at predict.c:1772 with…

re PR middle-end/71619 (ICE: in predict_loops, at predict.c:1772 with --param=max-predicted-iterations=0)

Fix PR middle-end/71619

	PR middle-end/71619
	* predict.c (predict_loops): Revert the hunk that was removed
	in r237103.
	* gcc.dg/pr71619.c: New test.

From-SVN: r237730

gcc/ChangeLog

+2016-06-23  Martin Liska  <mliska@suse.cz>
+
+	PR middle-end/71619
+	* predict.c (predict_loops): Revert the hunk that was removed
+	in r237103.
+
 2016-06-23  Jakub Sejdak  <jakub.sejdak@phoesys.com>
 
 	* config.gcc: Add support for arm*-*-phoenix* targets.

gcc/predict.c

@@ -1769,7 +1769,11 @@ predict_loops (void)
 	  else
 	    continue;
 
-	  gcc_checking_assert (nitercst);
+	  /* If the prediction for number of iterations is zero, do not
+	     predict the exit edges.  */
+	  if (nitercst == 0)
+	    continue;
+
 	  probability = RDIV (REG_BR_PROB_BASE, nitercst);
 	  predict_edge (ex, predictor, probability);
 	}

gcc/testsuite/ChangeLog

+2016-06-23  Martin Liska  <mliska@suse.cz>
+
+	* gcc.dg/pr71619.c: New test.
+
 2016-06-23  H.J. Lu  <hongjiu.lu@intel.com>
 
 	PR target/67400

gcc/testsuite/gcc.dg/pr71619.c

+/* PR 71619 */
+
+/* { dg-do compile } */
+/* { dg-options "-O --param=max-predicted-iterations=0" } */
+
+void
+foo ()
+{
+  int count = -10;
+  while (count++);
+}