[MIPS] Add remaining parts for building tests for MIPS

tests/barebones/barebones.h

Index: tests/barebones/barebones.h
diff --git a/tests/barebones/barebones.h b/tests/barebones/barebones.h
index a955bebb005742ee75a751afe898e3ea8da4ff33..e99cc111e25b242a469874ec856b9ca0a0ba3b75 100644
--- a/tests/barebones/barebones.h
+++ b/tests/barebones/barebones.h
@@ -1,7 +1,7 @@
 /*
- * Copyright 2010 The Native Client Authors. All rights reserved.
- * Use of this source code is governed by a BSD-style license that can
- * be found in the LICENSE file.
+ * Copyright (c) 2010 The Native Client Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
  */
 
 /*
@@ -34,6 +34,13 @@ typedef void (*TYPE_nacl_exit) (int status);
 #define THIS_IS_ALWAYS_FALSE_FOR_SMALL_NUMBERS(n) \
   (n * n - 1 != (n + 1) * (n - 1))
 
+
+#if defined(__mips__)
+# define NACL_STACK_ALIGN_MASK      (0x7)

[Roland McGrath, 2013/02/13 19:28:39]

We want this to be consistent across machines at 16.
Even if there is no special benefit on mips to a 16-byte aligned stack, we want
to reduce the differences between machines.

[Mark Seaborn, 2013/02/13 22:14:09]

Right.  While we don't need MIPS to over-align in generated code, and PNaCl
bitcode specifically shouldn't need to know about stack alignment, there's no
need to complicate the tests with ifdefs for smaller alignments when larger
alignments will do.

[petarj, 2013/02/14 18:04:14]

The return value specified in barebones_stack_alignment16.c as 
(55 + ((int)__builtin_dwarf_cfa() & NACL_STACK_ALIGN_MASK))

will be different for MIPS if we leave the same stack alignment, and
the test will fail.

[petarj, 2013/03/05 17:50:04]

I will revert this part of the change and remove
barebones_stack_alignment16.c in a separate change.

+#else
+# define NACL_STACK_ALIGN_MASK      (0xf)
+#endif
+
 int mystrlen(const char* s) {
   int count = 0;
   while (*s++) ++count;