Support multi-byte nop instructions as recommended by

test/cctest/test-disasm-ia32.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 431 matching lines @@
   }
 
   {
     if (CpuFeatures::IsSupported(SSE4_1)) {
       CpuFeatures::Scope scope(SSE4_1);
       __ pextrd(eax, xmm0, 1);
       __ pinsrd(xmm1, eax, 0);
     }
   }
 
+  // Nop instructions
+  for (int i = 0; i < 16; i++) {
+    __ Nop(i);
+  }
+
   __ ret(0);
 
   CodeDesc desc;
   assm.GetCode(&desc);
   Object* code = HEAP->CreateCode(
       desc,
       Code::ComputeFlags(Code::STUB),
       Handle<Object>(HEAP->undefined_value()))->ToObjectChecked();
   CHECK(code->IsCode());
 #ifdef OBJECT_PRINT
   Code::cast(code)->Print();
   byte* begin = Code::cast(code)->instruction_start();
   byte* end = begin + Code::cast(code)->instruction_size();
   disasm::Disassembler::Disassemble(stdout, begin, end);
 #endif
 }
 
 #undef __