Clean up the usage of V8_TARGET_ARCH_${arch} and V8_HOST_ARCH_${arch}

src/platform-win32.cc

 // Copyright 2012 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 129 matching lines @@
 }
 
 
 double ceiling(double x) {
   return ceil(x);
 }
 
 
 static Mutex* limit_mutex = NULL;
 
-#if defined(V8_TARGET_ARCH_IA32)
+#if V8_TARGET_ARCH_IA32
 static void MemMoveWrapper(void* dest, const void* src, size_t size) {
   memmove(dest, src, size);
 }
 
 // Initialize to library version so we can call this at any time during startup.
 static OS::MemMoveFunction memmove_function = &MemMoveWrapper;
 
 // Defined in codegen-ia32.cc.
 OS::MemMoveFunction CreateMemMoveFunction();
 
@@ skipping 412 matching lines @@
   // Return the standard or DST time zone name based on whether daylight
   // saving is in effect at the given time.
   return InDST() ? dst_tz_name_ : std_tz_name_;
 }
 
 
 void OS::PostSetUp() {
   // Math functions depend on CPU features therefore they are initialized after
   // CPU.
   MathSetup();
-#if defined(V8_TARGET_ARCH_IA32)
+#if V8_TARGET_ARCH_IA32
   OS::MemMoveFunction generated_memmove = CreateMemMoveFunction();
   if (generated_memmove != NULL) {
     memmove_function = generated_memmove;
   }
 #endif
 }
 
 
 // Returns the accumulated user time for thread.
 int OS::GetUserTime(uint32_t* secs,  uint32_t* usecs) {
@@ skipping 1387 matching lines @@
   limit_mutex = CreateMutex();
 }
 
 
 void OS::TearDown() {
   delete limit_mutex;
 }
 
 
 } }  // namespace v8::internal