re PR tree-optimization/69170 (ICE (segfault) in find_uses_to_rename_use)

2016-01-18  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/69170
	* tree-vect-slp.c (vect_build_slp_tree): Verify we are not
	building a vector from scalar results of a pattern stmt.

	* gcc.dg/torture/pr69170.c: New testcase.

From-SVN: r232496

gcc/ChangeLog

+2016-01-18  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/69170
+	* tree-vect-slp.c (vect_build_slp_tree): Verify we are not
+	building a vector from scalar results of a pattern stmt.
+
 2016-01-18  Jakub Jelinek  <jakub@redhat.com>
 
 	* haifa-sched.c (autopref_multipass_init): Work around

gcc/testsuite/ChangeLog

+2016-01-18  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/69170
+	* gcc.dg/torture/pr69170.c: New testcase.
+
 2016-01-17 John David Anglin  <danglin@gcc.gnu.org>
 
 	* gcc.dg/torture/builtin-integral-1.c: Require c99_runtime.

gcc/testsuite/gcc.dg/torture/pr69170.c

+/* { dg-do compile } */
+
+typedef long sha2_word_t;
+typedef struct {
+    sha2_word_t length_upper, length_lower;
+    char buf[];
+} hash_state;
+int a;
+hash_state b;
+void fn1()
+{
+  a = 0;
+  for (; a < 8; a++)
+    b.buf[a + 1024 / 8] = b.length_upper >> (1 - a) * 5;
+  a = 0;
+  for (; a < 8; a++)
+    b.buf[a + 1024 / 8 + 8] = b.length_lower >> (1 - a) * 5;
+}

gcc/tree-vect-slp.c

@@ -966,7 +966,12 @@ vect_build_slp_tree (vec_info *vinfo,
 	{
 	  /* If we have all children of child built up from scalars then just
 	     throw that away and build it up this node from scalars.  */
-	  if (!SLP_TREE_CHILDREN (child).is_empty ())
+	  if (!SLP_TREE_CHILDREN (child).is_empty ()
+	      /* ???  Rejecting patterns this way doesn't work.  We'd have to
+		 do extra work to cancel the pattern so the uses see the
+		 scalar version.  */
+	      && !is_pattern_stmt_p
+	            (vinfo_for_stmt (SLP_TREE_SCALAR_STMTS (child)[0])))
 	    {
 	      slp_tree grandchild;
 
@@ -1110,7 +1115,12 @@ vect_build_slp_tree (vec_info *vinfo,
 
 	      /* If we have all children of child built up from scalars then
 		 just throw that away and build it up this node from scalars.  */
-	      if (!SLP_TREE_CHILDREN (child).is_empty ())
+	      if (!SLP_TREE_CHILDREN (child).is_empty ()
+		  /* ???  Rejecting patterns this way doesn't work.  We'd have
+		     to do extra work to cancel the pattern so the uses see the
+		     scalar version.  */
+		  && !is_pattern_stmt_p
+			(vinfo_for_stmt (SLP_TREE_SCALAR_STMTS (child)[0])))
 		{
 		  unsigned int j;
 		  slp_tree grandchild;