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

src/x64/lithium-codegen-x64.cc

 // Copyright 2013 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 148 matching lines @@
       __ bind(&ok);
     }
   }
 
   info()->set_prologue_offset(masm_->pc_offset());
   if (NeedsEagerFrame()) {
     ASSERT(!frame_is_built_);
     frame_is_built_ = true;
     __ 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
+    }
     if (info()->IsStub()) {
       __ Push(Smi::FromInt(StackFrame::STUB));
     } else {
       __ push(rdi);  // Callee's JS function.
     }
     info()->AddNoFrameRange(0, masm_->pc_offset());
   }
 
   // Reserve space for the stack slots needed by the code.
   int slots = GetStackSlotCount();
@@ skipping 5339 matching lines @@
                                FixedArray::kHeaderSize - kPointerSize));
   __ bind(&done);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64