2015-03-13  Jakub Jelinek  <jakub@redhat.com>

	PR tree-optimization/65369
	* tree-vect-stmts.c (vectorizable_load) <case dr_explicit_realign>:
	Set bump to vs * TYPE_SIZE_UNIT (elem_type) - 1 instead of
	(vs - 1) * TYPE_SIZE_UNIT (elem_type).

	* gcc.c-torture/execute/pr65369.c: New test.

--- gcc/tree-vect-stmts.c.jj	2015-03-09 08:05:13.000000000 +0100
+++ gcc/tree-vect-stmts.c	2015-03-13 17:27:30.613529768 +0100
@@ -6468,9 +6468,8 @@ vectorizable_load (gimple stmt, gimple_s
 		case dr_explicit_realign:
 		  {
 		    tree ptr, bump;
-		    tree vs_minus_1;
 
-		    vs_minus_1 = size_int (TYPE_VECTOR_SUBPARTS (vectype) - 1);
+		    tree vs = size_int (TYPE_VECTOR_SUBPARTS (vectype));
 
 		    if (compute_in_loop)
 		      msq = vect_setup_realignment (first_stmt, gsi,
@@ -6499,8 +6498,9 @@ vectorizable_load (gimple stmt, gimple_s
 		    vect_finish_stmt_generation (stmt, new_stmt, gsi);
 		    msq = new_temp;
 
-		    bump = size_binop (MULT_EXPR, vs_minus_1,
+		    bump = size_binop (MULT_EXPR, vs,
 				       TYPE_SIZE_UNIT (elem_type));
+		    bump = size_binop (MINUS_EXPR, bump, size_one_node);
 		    ptr = bump_vector_ptr (dataref_ptr, NULL, gsi, stmt, bump);
 		    new_stmt = gimple_build_assign
 				 (NULL_TREE, BIT_AND_EXPR, ptr,
--- gcc/testsuite/gcc.c-torture/execute/pr65369.c.jj	2015-03-13 17:37:10.926175685 +0100
+++ gcc/testsuite/gcc.c-torture/execute/pr65369.c	2015-03-13 17:35:40.000000000 +0100
@@ -0,0 +1,45 @@
+/* PR tree-optimization/65369 */
+
+static const char data[] =
+  "12345678901234567890123456789012345678901234567890"
+  "123456789012345678901234567890";
+
+__attribute__ ((noinline))
+static void foo (const unsigned int *buf)
+{
+  if (__builtin_memcmp (buf, data, 64))
+    __builtin_abort ();
+}
+
+__attribute__ ((noinline))
+static void bar (const unsigned char *block)
+{
+  unsigned int buf[16];
+  __builtin_memcpy (buf +  0, block +  0, 4);
+  __builtin_memcpy (buf +  1, block +  4, 4);
+  __builtin_memcpy (buf +  2, block +  8, 4);
+  __builtin_memcpy (buf +  3, block + 12, 4);
+  __builtin_memcpy (buf +  4, block + 16, 4);
+  __builtin_memcpy (buf +  5, block + 20, 4);
+  __builtin_memcpy (buf +  6, block + 24, 4);
+  __builtin_memcpy (buf +  7, block + 28, 4);
+  __builtin_memcpy (buf +  8, block + 32, 4);
+  __builtin_memcpy (buf +  9, block + 36, 4);
+  __builtin_memcpy (buf + 10, block + 40, 4);
+  __builtin_memcpy (buf + 11, block + 44, 4);
+  __builtin_memcpy (buf + 12, block + 48, 4);
+  __builtin_memcpy (buf + 13, block + 52, 4);
+  __builtin_memcpy (buf + 14, block + 56, 4);
+  __builtin_memcpy (buf + 15, block + 60, 4);
+  foo (buf);
+}
+
+int
+main ()
+{
+  unsigned char input[sizeof data + 16] __attribute__((aligned (16)));
+  __builtin_memset (input, 0, sizeof input);
+  __builtin_memcpy (input + 1, data, sizeof data);
+  bar (input + 1);
+  return 0;
+}