fix x32 handling of Atomic64

src/atomicops.h

 // Copyright 2010 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 40 matching lines @@
 #include "../include/v8.h"
 #include "globals.h"
 
 namespace v8 {
 namespace internal {
 
 typedef int32_t Atomic32;
 #ifdef V8_HOST_ARCH_64_BIT
 // We need to be able to go between Atomic64 and AtomicWord implicitly.  This
 // means Atomic64 and AtomicWord should be the same type on 64-bit.
-#if defined(__APPLE__)
+#if defined(__ILP32__) || defined(__APPLE__)

[Brad Chen (chromium), 2013/03/04 23:27:32]

So, actually trying this in my own build, I'm not sure we actually want
V8_HOST_ARCH_64_BIT for the ILP32 build. Have you thought through this?

Note for example in globals.h:247; this code would have to be fixed too.

 // MacOS is an exception to the implicit conversion rule above,
 // because it uses long for intptr_t.
 typedef int64_t Atomic64;
 #else
 typedef intptr_t Atomic64;
 #endif
 #endif
 
 // Use AtomicWord for a machine-sized pointer.  It will use the Atomic32 or
 // Atomic64 routines below, depending on your architecture.
@@ skipping 92 matching lines @@
 #include "atomicops_internals_x86_gcc.h"
 #elif defined(__GNUC__) && defined(V8_HOST_ARCH_ARM)
 #include "atomicops_internals_arm_gcc.h"
 #elif defined(__GNUC__) && defined(V8_HOST_ARCH_MIPS)
 #include "atomicops_internals_mips_gcc.h"
 #else
 #error "Atomic operations are not supported on your platform"
 #endif
 
 #endif  // V8_ATOMICOPS_H_