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 146 matching lines @@
       __ LoadRoot(kScratchRegister, Heap::kUndefinedValueRootIndex);
       __ movq(Operand(rsp, receiver_offset), kScratchRegister);
       __ 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 (info()->IsStub()) {
-      __ Push(Smi::FromInt(StackFrame::STUB));
+    if (FLAG_optimize_for_size && FLAG_age_code && !info()->IsStub()) {
+        // Pre-age the code.
+      __ Call(isolate()->builtins()->MarkCodeAsExecutedOnce(),
+             RelocInfo::CODE_AGE_SEQUENCE);
+      for (int i = Assembler::kShortCallInstructionLength;
+           i < kNoCodeAgeSequenceLength;
+           i++) {
+        __ nop();
+      }
     } else {
-      __ push(rdi);  // Callee's JS function.
+      __ push(rbp);  // Caller's frame pointer.
+      __ movq(rbp, rsp);
+      __ 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();
   if (slots > 0) {
     if (FLAG_debug_code) {
       __ subq(rsp, Immediate(slots * kPointerSize));
 #ifdef _MSC_VER
@@ skipping 5327 matching lines @@
                                FixedArray::kHeaderSize - kPointerSize));
   __ bind(&done);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64