[module] Track script "module code" status

src/compiler.cc

Index: src/compiler.cc
diff --git a/src/compiler.cc b/src/compiler.cc
index 72cdc038ebfdb39e96573e6f49433dd84a292bc7..113c1b398f65fcaba3a4690f05cbebd6c3538838 100644
--- a/src/compiler.cc
+++ b/src/compiler.cc
@@ -1488,7 +1488,7 @@ Handle<SharedFunctionInfo> Compiler::GetSharedFunctionInfoForScript(
     // First check per-isolate compilation cache.
     maybe_result = compilation_cache->LookupScript(
         source, script_name, line_offset, column_offset, resource_options,
-        context, language_mode);
+        context, language_mode, is_module);
     if (maybe_result.is_null() && FLAG_serialize_toplevel &&
         compile_options == ScriptCompiler::kConsumeCodeCache &&
         !isolate->debug()->is_loaded()) {
@@ -1501,7 +1501,8 @@ Handle<SharedFunctionInfo> Compiler::GetSharedFunctionInfoForScript(
       if (CodeSerializer::Deserialize(isolate, *cached_data, source)
               .ToHandle(&result)) {
         // Promote to per-isolate compilation cache.
-        compilation_cache->PutScript(source, context, language_mode, result);
+        compilation_cache->PutScript(source, context, language_mode, is_module,
+                                     result);
         return result;
       }
       // Deserializer failed. Fall through to compile.
@@ -1537,14 +1538,19 @@ Handle<SharedFunctionInfo> Compiler::GetSharedFunctionInfoForScript(
     if (!source_map_url.is_null()) {
       script->set_source_mapping_url(*source_map_url);
     }
+    script->set_is_module(is_module);
 
     // Compile the function and add it to the cache.
     Zone zone(isolate->allocator());
     ParseInfo parse_info(&zone, script);
     CompilationInfo info(&parse_info, Handle<JSFunction>::null());
     if (is_module) {
-      parse_info.set_module();
+      // The ParseInfo constructor unconditionally sets the `is_module` bit
+      // when its script is module code.
+      DCHECK(parse_info.is_module());
     } else {
+      // In the current context of script compilation, the input cannot be eval
+      // code, so the input must be global code.
       parse_info.set_global();
     }
     if (compile_options != ScriptCompiler::kNoCompileOptions) {
@@ -1562,7 +1568,8 @@ Handle<SharedFunctionInfo> Compiler::GetSharedFunctionInfoForScript(
         static_cast<LanguageMode>(parse_info.language_mode() | language_mode));
     result = CompileToplevel(&info);
     if (extension == NULL && !result.is_null()) {
-      compilation_cache->PutScript(source, context, language_mode, result);
+      compilation_cache->PutScript(source, context, language_mode, is_module,
+                                   result);
       if (FLAG_serialize_toplevel &&
           compile_options == ScriptCompiler::kProduceCodeCache) {
         HistogramTimerScope histogram_timer(