[Interpreter] Removes unnecessary jumps and dead code from If and loops.

test/cctest/interpreter/test-interpreter.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.
 
 // TODO(rmcilroy): Remove this define after this flag is turned on globally
 #define V8_IMMINENT_DEPRECATION_WARNINGS
 
 #include "src/v8.h"
 
 #include "src/execution.h"
@@ skipping 2559 matching lines @@
                      "  b = b * 2;\n"
                      "  --a;\n"
                      "} while(a);\n"
                      "return b;\n",
                      handle(Smi::FromInt(2), isolate)),
       std::make_pair("var b = 1;\n"
                      "for ( var a = 10; a > 0; a--) {\n"
                      "  b *= 2;\n"
                      "}\n"
                      "return b;",
-                     factory->NewHeapNumber(1024))};
+                     factory->NewHeapNumber(1024)),
+      std::make_pair("var a = 10; var b = 1;\n"
+                     "while (false) {\n"
+                     "  b = b * 2;\n"
+                     "  a = a - 1;\n"
+                     "}\n"
+                     "return b;\n",
+                     Handle<Object>(Smi::FromInt(1), isolate)),
+      std::make_pair("var a = 10; var b = 1;\n"
+                     "while (true) {\n"
+                     "  b = b * 2;\n"
+                     "  a = a - 1;\n"
+                     "  if (a == 0) break;"
+                     "  continue;"
+                     "}\n"
+                     "return b;\n",
+                     factory->NewHeapNumber(1024)),
+      std::make_pair("var a = 10; var b = 1;\n"
+                     "do {\n"
+                     "  b = b * 2;\n"
+                     "  a = a - 1;\n"
+                     "  if (a == 0) break;"
+                     "} while(true);\n"
+                     "return b;\n",
+                     factory->NewHeapNumber(1024)),
+      std::make_pair("var a = 10; var b = 1;\n"
+                     "do {\n"
+                     "  b = b * 2;\n"
+                     "  a = a - 1;\n"
+                     "  if (a == 0) break;"
+                     "} while(false);\n"
+                     "return b;\n",
+                     Handle<Object>(Smi::FromInt(2), isolate)),
+      std::make_pair("var a = 10; var b = 1;\n"
+                     "for ( a = 1, b = 30; false; ) {\n"
+                     "  b = b * 2;\n"
+                     "}\n"
+                     "return b;\n",
+                     Handle<Object>(Smi::FromInt(30), isolate))};
 
   for (size_t i = 0; i < arraysize(loops); i++) {
     std::string source(InterpreterTester::SourceForBody(loops[i].first));
     InterpreterTester tester(handles.main_isolate(), source.c_str());
     auto callable = tester.GetCallable<>();
 
     Handle<i::Object> return_value = callable().ToHandleChecked();
     CHECK(return_value->SameValue(*loops[i].second));
   }
 }
@@ skipping 265 matching lines @@
     auto callable = tester.GetCallable<>();
 
     Handle<i::Object> return_value = callable().ToHandleChecked();
     CHECK(return_value->SameValue(*switch_ops[i].second));
   }
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8