Simplify pushing function argument for context allocation.

src/x64/full-codegen-x64.cc

 // Copyright 2011 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 4101 matching lines @@
   ASSERT(IsAligned(frame_offset, kPointerSize));
   __ movq(Operand(rbp, frame_offset), value);
 }
 
 
 void FullCodeGenerator::LoadContextField(Register dst, int context_index) {
   __ movq(dst, ContextOperand(rsi, context_index));
 }
 
 
-void FullCodeGenerator::PushFunctionArgumentForContextAllocation() {
+void FullCodeGenerator::PushFunctionArgumentForContextAllocation(
+    Register scratch) {
   Scope* declaration_scope = scope()->DeclarationScope();
   if (declaration_scope->is_global_scope()) {
     // Contexts nested in the global context have a canonical empty function
     // as their closure, not the anonymous closure containing the global
-    // code.  Pass a smi sentinel and let the runtime look up the empty
-    // function.
-    __ Push(Smi::FromInt(0));
+    // code.
+    __ movq(scratch, GlobalObjectOperand());
+    __ movq(scratch, FieldOperand(scratch, GlobalObject::kGlobalContextOffset));
+    __ push(ContextOperand(scratch, Context::CLOSURE_INDEX));
   } else if (declaration_scope->is_eval_scope()) {
     // Contexts created by a call to eval have the same closure as the
     // context calling eval, not the anonymous closure containing the eval
     // code.  Fetch it from the context.
     __ push(ContextOperand(rsi, Context::CLOSURE_INDEX));
   } else {
     ASSERT(declaration_scope->is_function_scope());
     __ push(Operand(rbp, JavaScriptFrameConstants::kFunctionOffset));
   }
 }
@@ skipping 56 matching lines @@
   *context_length = 0;
   return previous_;
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64