From: marxin <marxin@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Thu, 23 Jun 2016 11:04:35 +0000 (+0000)
Subject: Fix PR middle-end/71619
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=afa7ed877d72f2514673901cbd2c7779f8d4f880;p=thirdparty%2Fgcc.git

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.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@237730 138bc75d-0d04-0410-961f-82ee72b054a4
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 81f1b4d8a55b..850a3caf7365 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+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.
diff --git a/gcc/predict.c b/gcc/predict.c
index 470de8a6e373..d505d9c4cc80 100644
--- a/gcc/predict.c
+++ b/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);
 	}
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 54a1d4755d87..287baf6dcd8b 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+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
diff --git a/gcc/testsuite/gcc.dg/pr71619.c b/gcc/testsuite/gcc.dg/pr71619.c
new file mode 100644
index 000000000000..e1404bc9a9f1
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr71619.c
@@ -0,0 +1,11 @@
+/* PR 71619 */
+
+/* { dg-do compile } */
+/* { dg-options "-O --param=max-predicted-iterations=0" } */
+
+void
+foo ()
+{
+  int count = -10;
+  while (count++);
+}