[interpreter] Add a fast path for dynamic local load

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 <fstream>
 
 #include "src/v8.h"
 
 #include "src/interpreter/bytecode-array-iterator.h"
 #include "src/interpreter/bytecode-generator.h"
@@ skipping 1781 matching lines @@
       "return eval('1;');\n",
   };
 
   CHECK(
       CompareTexts(BuildActual(printer, snippets), LoadGolden("Eval.golden")));
 }
 
 TEST(LookupSlot) {
   InitializedIgnitionHandleScope scope;
   BytecodeExpectationsPrinter printer(CcTest::isolate());
+  printer.set_test_function_name("f");
 
+  // clang-format off
   const char* snippets[] = {
       "eval('var x = 10;'); return x;\n",
 
       "eval('var x = 10;'); return typeof x;\n",
 
       "x = 20; return eval('');\n",
+
+      "var x = 20;\n"
+      "f = function(){\n"
+      "  eval('var x = 10');\n"
+      "  return x;\n"
+      "}\n"
+      "f();\n"
   };
+  // clang-format on
 
   CHECK(CompareTexts(BuildActual(printer, snippets),
                      LoadGolden("LookupSlot.golden")));
 }
 
 TEST(CallLookupSlot) {
   InitializedIgnitionHandleScope scope;
   BytecodeExpectationsPrinter printer(CcTest::isolate());
   const char* snippets[] = {
       "g = function(){}; eval(''); return g();\n",
@@ skipping 364 matching lines @@
       "f();\n",
   };
 
   CHECK(CompareTexts(BuildActual(printer, snippets),
                      LoadGolden("Generators.golden")));
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8