From: Richard Biener <rguenther@suse.de>
Date: Tue, 5 Nov 2013 15:08:43 +0000 (+0000)
Subject: re PR tree-optimization/58955 (wrong code at -O3 on x86_64-linux-gnu)
X-Git-Tag: releases/gcc-4.9.0~3029
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=d8f4f4db4b6ff7e9ee02ca396093af282318ec9c;p=thirdparty%2Fgcc.git

re PR tree-optimization/58955 (wrong code at -O3 on x86_64-linux-gnu)

2013-11-05  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/58955
	* tree-loop-distribution.c (pg_add_dependence_edges): Fix
	edge direction.

	* gcc.dg/torture/pr58955-1.c: New testcase.
	* gcc.dg/torture/pr58955-2.c: Likewise.

From-SVN: r204398
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 938d62b7dd5b..ce16f50cf2ff 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2013-11-05  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/58955
+	* tree-loop-distribution.c (pg_add_dependence_edges): Fix
+	edge direction.
+
 2013-11-05  Bill Schmidt  <wschmidt@linux.vnet.ibm.com>
 
 	* config/rs6000/vector.md (vec_pack_sfix_trunc_v2df): Adjust for
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 21864c690c7c..07e418d4ff19 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2013-11-05  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/58955
+	* gcc.dg/torture/pr58955-1.c: New testcase.
+	* gcc.dg/torture/pr58955-2.c: Likewise.
+
 2013-11-05  H.J. Lu  <hongjiu.lu@intel.com>
 
 	PR middle-end/58981
diff --git a/gcc/testsuite/gcc.dg/torture/pr58955-1.c b/gcc/testsuite/gcc.dg/torture/pr58955-1.c
new file mode 100644
index 000000000000..a79f42f0b38b
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr58955-1.c
@@ -0,0 +1,20 @@
+/* { dg-do run } */
+
+extern void abort (void);
+
+int a, b, c, d[4] = { 0, 0, 0, 1 };
+
+int
+main ()
+{
+  for (; a < 4; a++)
+    {
+      int e = d[a];
+      for (c = 1; c < 1; c++);
+      b = e;
+      d[a] = 0;
+    }
+  if (b != 1)
+    abort ();
+  return 0;
+}
diff --git a/gcc/testsuite/gcc.dg/torture/pr58955-2.c b/gcc/testsuite/gcc.dg/torture/pr58955-2.c
new file mode 100644
index 000000000000..a43860e9b020
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr58955-2.c
@@ -0,0 +1,18 @@
+/* { dg-do run } */
+
+extern void abort (void);
+
+int a, b[10];
+
+int
+main ()
+{
+  for (; a < 2; a++)
+    {
+      b[a] = 1;
+      b[a + 1] = 0;
+    }
+  if (b[1] != 1)
+    abort ();
+  return 0;
+}
diff --git a/gcc/tree-loop-distribution.c b/gcc/tree-loop-distribution.c
index 79884bf42726..4f9b848847a9 100644
--- a/gcc/tree-loop-distribution.c
+++ b/gcc/tree-loop-distribution.c
@@ -1324,7 +1324,7 @@ pg_add_dependence_edges (struct graph *rdg, vec<loop_p> loops, int dir,
   for (int ii = 0; drs1.iterate (ii, &dr1); ++ii)
     for (int jj = 0; drs2.iterate (jj, &dr2); ++jj)
       {
-	int this_dir = 1;
+	int this_dir = -1;
 	ddr_p ddr;
 	/* Re-shuffle data-refs to be in dominator order.  */
 	if (rdg_vertex_for_stmt (rdg, DR_STMT (dr1))