Treat a '!' preceding a function literal as eager-compile hint.

test/cctest/parsing/test-parse-decision.cc

+// Copyright 2016 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.
+
+// Test specific cases of the lazy/eager-parse decision.
+//
+// Note that presently most unit tests for parsing are found in
+// cctest/test-parsing.cc.
+
+#include <unordered_map>
+
+#include "include/v8.h"
+#include "src/api.h"
+#include "src/handles-inl.h"
+#include "src/isolate.h"
+#include "src/utils.h"
+
+#include "test/cctest/cctest.h"
+
+using namespace v8::internal;
+
+TEST(EagerlyCompileImmediateUseFunctions) {
+  if (!FLAG_lazy) return;
+  FLAG_min_preparse_length = 0;
+
+  const char src[] =
+      "function normal() { var a; }\n"             // Normal: Should lazy parse.
+      "(function parenthesized() { var b; })()\n"  // Parenthesized: Pre-parse.
+      "!function exclaimed() { var c; }() \n"      // Exclaimed: Pre-parse.
+      "function normal2() { var d; }\n";           // Normal function again.
+
+  Isolate* isolate = CcTest::i_isolate();
+  HandleScope scope(isolate);
+  LocalContext env;
+
+  // Compile src & record the 'compiled' state of all top level functions in
+  // is_compiled.
+  std::unordered_map<std::string, bool> is_compiled;
+  {
+    v8::Local<v8::Script> api_script = v8_compile(src);
+    Handle<JSFunction> toplevel_fn = v8::Utils::OpenHandle(*api_script);
+    Handle<Script> script =
+        handle(Script::cast(toplevel_fn->shared()->script()));
+
+    WeakFixedArray::Iterator iter(script->shared_function_infos());
+    while (SharedFunctionInfo* shared = iter.Next<SharedFunctionInfo>()) {
+      std::unique_ptr<char[]> name = String::cast(shared->name())->ToCString();
+      is_compiled[name.get()] = shared->is_compiled();
+    }
+  }
+
+  DCHECK(is_compiled.find("normal") != is_compiled.end());
+
+  DCHECK(is_compiled["parenthesized"]);
+  DCHECK(is_compiled["exclaimed"]);
+  DCHECK(!is_compiled["normal"]);
+  DCHECK(!is_compiled["normal2"]);
+}