Enable preaging of code objects when --optimize-for-size.

src/x64/full-codegen-x64.cc

 // Copyright 2012 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 137 matching lines @@
   }
 
   // Open a frame scope to indicate that there is a frame on the stack.  The
   // MANUAL indicates that the scope shouldn't actually generate code to set up
   // the frame (that is done below).
   FrameScope frame_scope(masm_, StackFrame::MANUAL);
 
   info->set_prologue_offset(masm_->pc_offset());
   __ push(rbp);  // Caller's frame pointer.
   __ movq(rbp, rsp);
-  __ push(rsi);  // Callee's context.
+  if (isolate()->is_memory_constrained()) {
+    // This sequence marks pre-aged code.
+    __ push(rsi);  // Callee's context.
+    __ nop();
+  } else {
+    // This sequence marks non-aged code.
+    __ nop();
+    __ push(rsi);  // Callee's context
+  }
   __ push(rdi);  // Callee's JS Function.
   info->AddNoFrameRange(0, masm_->pc_offset());
 
   { Comment cmnt(masm_, "[ Allocate locals");
     int locals_count = info->scope()->num_stack_slots();
     // Generators allocate locals, if any, in context slots.
     ASSERT(!info->function()->is_generator() || locals_count == 0);
     if (locals_count == 1) {
       __ PushRoot(Heap::kUndefinedValueRootIndex);
     } else if (locals_count > 1) {
@@ skipping 4707 matching lines @@
   *context_length = 0;
   return previous_;
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64