Fix clobber removal in parloops

2016-01-23  Tom de Vries  <tom@codesourcery.com>

	PR tree-optimization/69426
	* tree-parloops.c (eliminate_local_variables_stmt): Handle vdef of
	removed clobber.

	* gcc.dg/autopar/pr69426.c: New test.

From-SVN: r232767

gcc/ChangeLog

@@ -1,3 +1,9 @@
+2016-01-23  Tom de Vries  <tom@codesourcery.com>
+
+	PR tree-optimization/69426
+	* tree-parloops.c (eliminate_local_variables_stmt): Handle vdef of
+	removed clobber.
+
 2016-01-23  Jakub Jelinek  <jakub@redhat.com>
 
 	* tree-ssanames.c (release_free_names_and_compact_live_names): Replace

gcc/testsuite/ChangeLog

@@ -1,3 +1,8 @@
+2016-01-23  Tom de Vries  <tom@codesourcery.com>
+
+	PR tree-optimization/69426
+	* gcc.dg/autopar/pr69426.c: New test.
+
 2016-01-23  Martin Sebor  <msebor@redhat.com>
 
 	PR c++/58109

gcc/testsuite/gcc.dg/autopar/pr69426.c

@@ -0,0 +1,19 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -ftree-parallelize-loops=2" } */
+
+int iq;
+
+void
+mr(void)
+{
+  unsigned int i8;
+
+  for (i8 = 0; i8 != 1; i8 += 3) {
+    void *f0[] = { f0 };
+    int hv;
+
+    for (; hv < 1; ++hv)
+      iq = 0;
+  }
+  ++iq;
+}

gcc/tree-parloops.c

@@ -725,6 +725,7 @@ eliminate_local_variables_stmt (edge entry, gimple_stmt_iterator *gsi,
     }
   else if (gimple_clobber_p (stmt))
     {
+      unlink_stmt_vdef (stmt);
       stmt = gimple_build_nop ();
       gsi_replace (gsi, stmt, false);
       dta.changed = true;