re PR tree-optimization/48377 (miscompilation at -O3)

	PR tree-optimization/48377
	* tree-vect-data-refs.c (vector_alignment_reachable_p): Set
	is_packed to true even for types with smaller TYPE_ALIGN than
	TYPE_SIZE.

	* gcc.dg/vect/pr48377.c: New test.

From-SVN: r172172

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 14bc365f801c671164636ce8a07fa38d0de28601..d149898ba139af81af20400ac803e27826d25d3d 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2011-04-08  Jakub Jelinek  <jakub@redhat.com>
+
+       PR tree-optimization/48377
+       * tree-vect-data-refs.c (vector_alignment_reachable_p): Set
+       is_packed to true even for types with smaller TYPE_ALIGN than
+       TYPE_SIZE.
+
 2011-04-08  Richard Guenther  <rguenther@suse.de>
 
        PR bootstrap/48513

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 436404b013631a09f692241439d5403c65566b8d..ca8666ad80a8c9e400027b9a764ff2562a23581b 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2011-04-08  Jakub Jelinek  <jakub@redhat.com>
+
+       PR tree-optimization/48377
+       * gcc.dg/vect/pr48377.c: New test.
+
 2011-04-07  Jason Merrill  <jason@redhat.com>
 
        * g++.dg/cpp0x/regress/call1.C: New.

diff --git a/gcc/testsuite/gcc.dg/vect/pr48377.c b/gcc/testsuite/gcc.dg/vect/pr48377.c
new file mode 100644 (file)
index 0000000..e0cde43
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/vect/pr48377.c
@@ -0,0 +1,25 @@
+/* PR tree-optimization/48377 */
+/* { dg-do run } */
+
+typedef unsigned int U __attribute__((__aligned__ (1), __may_alias__));
+
+__attribute__((noinline, noclone)) unsigned int
+foo (const char *s, int len)
+{
+  const U *p = (const U *) s;
+  unsigned int f = len / sizeof (unsigned int), hash = len, i;
+
+  for (i = 0; i < f; ++i)
+    hash += *p++;
+  return hash;
+}
+
+char buf[64] __attribute__((aligned (32)));
+
+int
+main (void)
+{
+  return foo (buf + 1, 26) != 26;
+}
+
+/* { dg-final { cleanup-tree-dump "vect" } } */

diff --git a/gcc/tree-vect-data-refs.c b/gcc/tree-vect-data-refs.c
index 8f411140880f83b00b085c77e6901f06349bf977..760bc41a30f72526465a68d288d6e7d3b4fb3fc5 100644 (file)
--- a/gcc/tree-vect-data-refs.c
+++ b/gcc/tree-vect-data-refs.c
@@ -1,5 +1,5 @@
 /* Data References Analysis and Manipulation Utilities for Vectorization.
-   Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
+   Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
    Free Software Foundation, Inc.
    Contributed by Dorit Naishlos <dorit@il.ibm.com>
    and Ira Rosen <irar@il.ibm.com>
@@ -1110,6 +1110,9 @@ vector_alignment_reachable_p (struct data_reference *dr)
       if (ba)
        is_packed = contains_packed_reference (ba);
 
+      if (compare_tree_int (TYPE_SIZE (type), TYPE_ALIGN (type)) > 0)
+       is_packed = true;
+
       if (vect_print_dump_info (REPORT_DETAILS))
        fprintf (vect_dump, "Unknown misalignment, is_packed = %d",is_packed);
       if (targetm.vectorize.vector_alignment_reachable (type, is_packed))