MIPS: Fix big-endian after r21774/r21803.

include/v8.h

Index: include/v8.h
diff --git a/include/v8.h b/include/v8.h
index 2739e070b634cac24804eb2e8813a7d451b13fb0..93fea484f2661f8aa2e7eea74e4c118aeeac7b26 100644
--- a/include/v8.h
+++ b/include/v8.h
@@ -5517,7 +5517,12 @@ class Internals {
   // These values match non-compiler-dependent values defined within
   // the implementation of v8.
   static const int kHeapObjectMapOffset = 0;
+#if defined (__BYTE_ORDER__) && (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)

[mtbrandy, 2014/06/17 17:11:39]

I think this is an argument for making the v8-endian definitions available here 
similar to the v8-os definitions.  Not all platforms define __BYTE_ORDER__.

[danno, 2014/06/18 11:18:41]

This probably means taking the entire contents of src/base/build_config.h and
putting it in v8config.h. Adding Jochen to see how that fits into his master
plan for refactoring base.

[Paul Lind, 2014/06/19 07:31:22]

By loading 16 bit word in this API accessor, but only using the LS 8 bits
(InstanceType), we can take advantage of the endianess, as Danno did in r21774.
And avoid conditional compilation here.

I think it would be good for the future to bring base/build_config.h into
v8config.h, or at least the CPU arch & endianess part of it, but we don't need
to do it for this issue.

+  static const int kMapInstanceTypeOffset =
+      1 * kApiPointerSize + kApiIntSize + 1;
+#else
   static const int kMapInstanceTypeOffset = 1 * kApiPointerSize + kApiIntSize;
+#endif
   static const int kStringResourceOffset = 3 * kApiPointerSize;
 
   static const int kOddballKindOffset = 3 * kApiPointerSize;