X64: Fix bugs affecting Win64.

src/execution.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 368 matching lines @@
   postpone_interrupts_nesting_ = 0;
   interrupt_flags_ = 0;
   Heap::SetStackLimit(kIllegalLimit);
 }
 
 
 void StackGuard::ThreadLocal::Initialize() {
   if (initial_climit_ == kIllegalLimit) {
     // Takes the address of the limit variable in order to find out where
     // the top of stack is right now.
-    intptr_t limit = reinterpret_cast<intptr_t>(&limit) - kLimitSize;
+    uintptr_t limit = reinterpret_cast<uintptr_t>(&limit) - kLimitSize;
+    ASSERT(reinterpret_cast<uintptr_t>(&limit) > kLimitSize);
     initial_jslimit_ = SimulatorStack::JsLimitFromCLimit(limit);
     jslimit_ = SimulatorStack::JsLimitFromCLimit(limit);
     initial_climit_ = limit;
     climit_ = limit;
     Heap::SetStackLimit(SimulatorStack::JsLimitFromCLimit(limit));
   }
   nesting_ = 0;
   postpone_interrupts_nesting_ = 0;
   interrupt_flags_ = 0;
 }
@@ skipping 292 matching lines @@
   // All allocation spaces other than NEW_SPACE have the same effect.
   Heap::CollectAllGarbage(false);
   return v8::Undefined();
 }
 
 
 static GCExtension kGCExtension;
 v8::DeclareExtension kGCExtensionDeclaration(&kGCExtension);
 
 } }  // namespace v8::internal