Cache current thread in a reserved register and use it in LoadIsolate

runtime/vm/dart_entry.cc

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/dart_entry.h"
 
 #include "vm/class_finalizer.h"
 #include "vm/code_generator.h"
 #include "vm/compiler.h"
 #include "vm/debugger.h"
@@ skipping 87 matching lines @@
   ScopedIsolateStackLimits stack_limit(isolate);
   SuspendLongJumpScope suspend_long_jump_scope(isolate);
 #if defined(USING_SIMULATOR)
 #if defined(ARCH_IS_64_BIT)
   // TODO(zra): Change to intptr_t so we have only one case.
     return bit_copy<RawObject*, int64_t>(Simulator::Current()->Call(
         reinterpret_cast<int64_t>(entrypoint),
         static_cast<int64_t>(code.EntryPoint()),
         reinterpret_cast<int64_t>(&arguments_descriptor),
         reinterpret_cast<int64_t>(&arguments),
-        0));
+        reinterpret_cast<int64_t>(thread)));
 #else
     return bit_copy<RawObject*, int64_t>(Simulator::Current()->Call(
         reinterpret_cast<int32_t>(entrypoint),
         static_cast<int32_t>(code.EntryPoint()),
         reinterpret_cast<int32_t>(&arguments_descriptor),
         reinterpret_cast<int32_t>(&arguments),
-        0));
+        reinterpret_cast<int32_t>(thread)));
 #endif
 #else
     return entrypoint(code.EntryPoint(),
                       arguments_descriptor,
-                      arguments);
+                      arguments,
+                      thread);
 #endif
 }
 
 
 RawObject* DartEntry::InvokeClosure(const Array& arguments) {
   const Array& arguments_descriptor =
       Array::Handle(ArgumentsDescriptor::New(arguments.Length()));
   return InvokeClosure(arguments, arguments_descriptor);
 }
 
@@ skipping 386 matching lines @@
   const Array& args = Array::Handle(Array::New(kNumArguments));
   args.SetAt(0, map);
   args.SetAt(1, key);
   args.SetAt(2, value);
   const Object& result = Object::Handle(DartEntry::InvokeFunction(function,
                                                                   args));
   return result.raw();
 }
 
 }  // namespace dart