[MIPS] Add remaining parts for building tests for MIPS

tests/barebones/barebones.h

 /*
- * 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.
  */
 
 /*
  * these were lifted from src/trusted/service_runtime/nacl_config.h
  * NOTE: we cannot include this file here
  * TODO(robertm): make this file available in the sdk
  * http://code.google.com/p/nativeclient/issues/detail?id=386
  */
 
 #ifndef BAREBONES_H_
@@ skipping 12 matching lines @@
 typedef void (*TYPE_nacl_exit) (int status);
 
 #include <bits/nacl_syscalls.h>
 
 
 #define myprint(s) NACL_SYSCALL(write)(1, s, mystrlen(s))
 
 #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;
   return count;
 }
 
 
 void myhextochar(int n, char buffer[9]) {
   int i;
   buffer[8] = 0;
 
   for (i = 0; i < 8; ++i) {
     int nibble = 0xf & (n >> (4 * (7 - i)));
     if (nibble <= 9) {
       buffer[i] = nibble + '0';
     } else {
       buffer[i] = nibble - 10 + 'A';
     }
   }
 }
 
 #endif  /* BAREBONES_H_ */