Fast path for strict closure creation.

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 1023 matching lines @@
   // Use the fast case closure allocation code that allocates in new
   // space for nested functions that don't need literals cloning. If
   // we're running with the --always-opt or the --prepare-always-opt
   // flag, we need to use the runtime function so that the new function
   // we are creating here gets a chance to have its code optimized and
   // doesn't just get a copy of the existing unoptimized code.
   if (!FLAG_always_opt &&
       !FLAG_prepare_always_opt &&
       !pretenure &&
       scope()->is_function_scope() &&
-      info->num_literals() == 0 &&
-      !info->strict_mode()) {  // Strict mode functions use slow path.
-    FastNewClosureStub stub;
+      info->num_literals() == 0) {
+    FastNewClosureStub stub(info->strict_mode() ? kStrictMode : kNonStrictMode);
     __ Push(info);
     __ CallStub(&stub);
   } else {
     __ push(rsi);
     __ Push(info);
     __ Push(pretenure ? Factory::true_value() : Factory::false_value());
     __ CallRuntime(Runtime::kNewClosure, 3);
   }
   context()->Plug(rax);
 }
@@ skipping 2910 matching lines @@
   __ ret(0);
 }
 
 
 #undef __
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64