Allow forcing the use of a simulator from the build script...

src/top.cc

 // Copyright 2006-2008 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 49 matching lines @@
 
 v8::TryCatch* ThreadLocalTop::TryCatchHandler() {
   return TRY_CATCH_FROM_ADDRESS(try_catch_handler_address());
 }
 
 
 void ThreadLocalTop::Initialize() {
   c_entry_fp_ = 0;
   handler_ = 0;
 #ifdef USE_SIMULATOR
+#ifdef V8_TARGET_ARCH_ARM
   simulator_ = assembler::arm::Simulator::current();
-#endif  // USE_SIMULATOR
+#elif V8_TARGET_ARCH_MIPS
+  simulator_ = assembler::mips::Simulator::current();
+#endif
+#endif
 #ifdef ENABLE_LOGGING_AND_PROFILING
   js_entry_sp_ = 0;
 #endif
 #ifdef ENABLE_VMSTATE_TRACKING
   current_vm_state_ = NULL;
 #endif
   try_catch_handler_address_ = NULL;
   context_ = NULL;
   int id = ThreadManager::CurrentId();
   thread_id_ = (id == 0) ? ThreadManager::kInvalidId : id;
@@ skipping 977 matching lines @@
   InitializeThreadLocal();
   return to + sizeof(thread_local_);
 }
 
 
 char* Top::RestoreThread(char* from) {
   memcpy(reinterpret_cast<char*>(&thread_local_), from, sizeof(thread_local_));
   // This might be just paranoia, but it seems to be needed in case a
   // thread_local_ is restored on a separate OS thread.
 #ifdef USE_SIMULATOR
+#ifdef V8_TARGET_ARCH_ARM
   thread_local_.simulator_ = assembler::arm::Simulator::current();
+#elif V8_TARGET_ARCH_MIPS
+  thread_local_.simulator_ = assembler::mips::Simulator::current();
+#endif
 #endif
   return from + sizeof(thread_local_);
 }
 
 
 ExecutionAccess::ExecutionAccess() {
   Top::break_access_->Lock();
 }
 
 
 ExecutionAccess::~ExecutionAccess() {
   Top::break_access_->Unlock();
 }
 
 
 } }  // namespace v8::internal