[PATCH] Fix loop-distribution

[Richard Biener]

This fixes the bug Jakub noticed - we fail to distribute all
stores and just drop them (oops).

Bootstrapped and tested on x86_64-unknown-linux-gnu, applied.

Richard.

2013-11-15  Richard Biener  <rguenther@suse.de>

	* tree-loop-distribution.c (tree_loop_distribution): Make sure
	to distribute all stores.

	* gcc.dg/torture/20131115-1.c: New testcase.

Index: gcc/tree-loop-distribution.c
===================================================================
--- gcc/tree-loop-distribution.c	(revision 204787)
+++ gcc/tree-loop-distribution.c	(working copy)
@@ -1723,8 +1723,7 @@ tree_loop_distribution (void)
 	      if (stmt_has_scalar_dependences_outside_loop (loop, stmt))
 		;
 	      /* Otherwise only distribute stores for now.  */
-	      else if (!gimple_assign_single_p (stmt)
-		       || is_gimple_reg (gimple_assign_lhs (stmt)))
+	      else if (!gimple_vdef (stmt))
 		continue;
 
 	      work_list.safe_push (stmt);
Index: gcc/testsuite/gcc.dg/torture/20131115-1.c
===================================================================
--- gcc/testsuite/gcc.dg/torture/20131115-1.c	(revision 0)
+++ gcc/testsuite/gcc.dg/torture/20131115-1.c	(working copy)
@@ -0,0 +1,38 @@
+/* { dg-do run } */
+
+struct S { int i; };
+__attribute__((const, noinline, noclone))
+struct S foo (int x)
+{
+  struct S s;
+  s.i = x;
+  return s;
+}
+
+int a[2048], b[2048], c[2048], d[2048];
+struct S e[2048];
+
+__attribute__((noinline, noclone)) void
+bar (void)
+{
+  int i;
+  for (i = 0; i < 1024; i++)
+    {
+      e[i] = foo (i);
+      a[i+2] = a[i] + a[i+1];
+      b[10] = b[10] + i;
+      c[i] = c[2047 - i];
+      d[i] = d[i + 1];
+    }
+}
+
+int
+main ()
+{
+  int i;
+  bar ();
+  for (i = 0; i < 1024; i++)
+    if (e[i].i != i)
+      __builtin_abort ();
+  return 0;
+}