re PR middle-end/30442 (Expanded array initialization can use memset builtin function)

2012-06-05  Richard Guenther  <rguenther@suse.de>

	PR tree-optimization/30442
	* tree-vect-data-refs.c (vect_analyze_data_refs): For basic-block
	vectorization stop analysis at the first stmt we cannot compute
	a data-reference for instead of giving up completely.

	* gcc.dg/vect/bb-slp-30.c: New testcase.

From-SVN: r188235

gcc/ChangeLog

 2012-06-05  Richard Guenther  <rguenther@suse.de>
 
+	PR tree-optimization/30442
+	* tree-vect-data-refs.c (vect_analyze_data_refs): For basic-block
+	vectorization stop analysis at the first stmt we cannot compute
+	a data-reference for instead of giving up completely.
+
+2012-06-05  Richard Guenther  <rguenther@suse.de>
+
 	* tree-loop-distribution.c (struct partition_s): Add has_writes
 	member.
 	(partition_alloc): Initialize it.

gcc/testsuite/ChangeLog

 2012-06-05  Richard Guenther  <rguenther@suse.de>
 
+	PR tree-optimization/30442
+	* gcc.dg/vect/bb-slp-30.c: New testcase.
+
+2012-06-05  Richard Guenther  <rguenther@suse.de>
+
 	PR tree-optimization/53081
 	* gcc.dg/tree-ssa/ldist-19.c: New testcase.
 	* gcc.c-torture/execute/builtins/builtins.exp: Always pass

gcc/testsuite/gcc.dg/vect/bb-slp-30.c

+/* { dg-require-effective-target vect_int } */
+
+int a[32];
+
+void __attribute__((noinline))
+test1(void)
+{
+  a[0] = 1;
+  a[1] = 1;
+  a[2] = 1;
+  a[3] = 1;
+  a[4] = 1;
+  a[5] = 1;
+  a[6] = 1;
+  a[7] = 1;
+  a[8] = 1;
+  a[9] = 1;
+  a[10] = 1;
+  a[11] = 1;
+  a[12] = 1;
+  a[13] = 1;
+  a[14] = 1;
+  a[15] = 1;
+  a[16] = 1;
+  a[17] = 1;
+  a[18] = 1;
+  a[19] = 1;
+  a[20] = 1;
+  a[21] = 1;
+  a[22] = 1;
+  a[23] = 1;
+  a[24] = 1;
+  a[25] = 1;
+  a[26] = 1;
+  a[27] = 1;
+  a[28] = 1;
+  a[29] = 1;
+  a[30] = 1;
+  a[31] = 1;
+  asm ("" : : : "memory");
+  a[21] = 0;
+}
+
+int main() { test1(); return a[21]; }
+
+/* { dg-final { scan-tree-dump-times "basic block vectorized using SLP" 1 "slp" } } */
+/* { dg-final { cleanup-tree-dump "slp" } } */

gcc/tree-vect-data-refs.c

@@ -2844,11 +2844,23 @@ vect_analyze_data_refs (loop_vec_info loop_vinfo,
     }
   else
     {
+      gimple_stmt_iterator gsi;
+
       bb = BB_VINFO_BB (bb_vinfo);
-      res = compute_data_dependences_for_bb (bb, true,
-					     &BB_VINFO_DATAREFS (bb_vinfo),
-					     &BB_VINFO_DDRS (bb_vinfo));
-      if (!res)
+      for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+	{
+	  gimple stmt = gsi_stmt (gsi);
+	  if (!find_data_references_in_stmt (NULL, stmt,
+					     &BB_VINFO_DATAREFS (bb_vinfo)))
+	    {
+	      /* Mark the rest of the basic-block as unvectorizable.  */
+	      for (; !gsi_end_p (gsi); gsi_next (&gsi))
+		STMT_VINFO_VECTORIZABLE (vinfo_for_stmt (stmt)) = false;
+	      break;
+	    }
+	}
+      if (!compute_all_dependences (BB_VINFO_DATAREFS (bb_vinfo),
+				    &BB_VINFO_DDRS (bb_vinfo), NULL, true))
 	{
 	  if (vect_print_dump_info (REPORT_UNVECTORIZED_LOCATIONS))
 	    fprintf (vect_dump, "not vectorized: basic block contains function"