[interpreter] Move temporary register allocator into own file.

test/cctest/interpreter/test-bytecode-generator.cc

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #include "src/compiler.h"
 #include "src/interpreter/bytecode-array-iterator.h"
 #include "src/interpreter/bytecode-generator.h"
 #include "src/interpreter/interpreter.h"
@@ skipping 7258 matching lines @@
     std::string script = std::string(function_prologue) +
                          std::string(snippets[i].code_snippet) +
                          std::string(function_epilogue);
     Handle<BytecodeArray> bytecode_array =
         helper.MakeBytecode(script.c_str(), "*", "f");
     CheckBytecodeArrayEqual(snippets[i], bytecode_array);
   }
 }
 
 TEST(WideRegisters) {
-  InitializedHandleScope handle_scope;
-  BytecodeGeneratorHelper helper;
-
   // Prepare prologue that creates frame for lots of registers.
   std::ostringstream os;
   for (size_t i = 0; i < 157; ++i) {
     os << "var x" << i << ";\n";
   }
   std::string prologue(os.str());
 
   ExpectedSnippet<int> snippets[] = {
       {"x0 = x127;\n"
        "return x0;\n",
@@ skipping 194 matching lines @@
            B(Ldar), R(125),                                          //
            B(Star), R(125),                                          //
            B(MovWide), R16(125), R16(162),                           //
            B(CallRuntimeWide), U16(Runtime::kAdd), R16(161), U8(2),  //
            B(Star), R(1),                                            //
            B(CallRuntime), U16(Runtime::kTheHole), R(0), U8(0),      //
            B(Ldar), R(1),                                            //
            B(Return),                                                //
        }}};
 
+  InitializedHandleScope handle_scope;
+  BytecodeGeneratorHelper helper;
+
   for (size_t i = 0; i < arraysize(snippets); ++i) {
     std::string body = prologue + snippets[i].code_snippet;
     Handle<BytecodeArray> bytecode_array =
         helper.MakeBytecodeForFunctionBody(body.c_str());
     CheckBytecodeArrayEqual(snippets[i], bytecode_array);
   }
 }
 
 TEST(DoExpression) {
   bool old_flag = FLAG_harmony_do_expressions;
@@ skipping 53 matching lines @@
     Handle<BytecodeArray> bytecode_array =
         helper.MakeBytecodeForFunctionBody(snippets[i].code_snippet);
     CheckBytecodeArrayEqual(snippets[i], bytecode_array);
   }
   FLAG_harmony_do_expressions = old_flag;
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8