[Interpreter] Implement do expressions.

test/cctest/compiler/test-run-bytecode-graph-builder.cc

Index: test/cctest/compiler/test-run-bytecode-graph-builder.cc
diff --git a/test/cctest/compiler/test-run-bytecode-graph-builder.cc b/test/cctest/compiler/test-run-bytecode-graph-builder.cc
index 9a01eda0e109a6241c9ae63ea0cd517238990dc8..a888d5ccdbe23c8dacadea7912a67fd54cac400d 100644
--- a/test/cctest/compiler/test-run-bytecode-graph-builder.cc
+++ b/test/cctest/compiler/test-run-bytecode-graph-builder.cc
@@ -2426,6 +2426,39 @@ TEST(JumpWithConstantsAndWideConstants) {
   }
 }
 
+TEST(BytecodeGraphBuilderDoExpressions) {
+  bool old_flag = FLAG_harmony_do_expressions;
+  FLAG_harmony_do_expressions = true;
+
+  HandleAndZoneScope scope;
+  Isolate* isolate = scope.main_isolate();
+  Zone* zone = scope.main_zone();
+  Factory* factory = isolate->factory();
+  ExpectedSnippet<0> snippets[] = {
+      {"var a = do {}; return a;", {factory->undefined_value()}},
+      {"var a = do { var x = 100; }; return a;", {factory->undefined_value()}},
+      {"var a = do { var x = 100; }; return a;", {factory->undefined_value()}},
+      {"var a = do { var x = 100; x++; }; return a;",
+       {handle(Smi::FromInt(100), isolate)}},
+      {"var i = 0; for (; i < 5;) { i = do { if (i == 3) { break; }; i + 1; }};"
+       "return i;",
+       {handle(Smi::FromInt(3), isolate)}},
+  };
+
+  for (size_t i = 0; i < arraysize(snippets); i++) {
+    ScopedVector<char> script(1024);
+    SNPrintF(script, "function %s() { %s }\n%s();", kFunctionName,
+             snippets[i].code_snippet, kFunctionName);
+
+    BytecodeGraphTester tester(isolate, zone, script.start());
+    auto callable = tester.GetCallable<>();
+    Handle<Object> return_value = callable().ToHandleChecked();
+    CHECK(return_value->SameValue(*snippets[i].return_value()));
+  }
+
+  FLAG_harmony_do_expressions = old_flag;
+}
+
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8