vm: make ContextifyContext template context-independent

Instead of creating an object template for every ContextifyContext, we now create one object template that can be reused by all contexts. The native pointer can be obtained through an embdder pointer field in the creation context of the receiver in the interceptors, because the interceptors are only meant to be invoked on the global object of the contextified contexts. This makes the ContextifyContext template context-independent and therefore snapshotable.
nodejs · Aug 17, 2022 · 1731a9f · 1731a9f
1 parent 12cc783
commit 1731a9f
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Showing 6 changed files with 164 additions and 113 deletions.
diff --git a/src/env.cc b/src/env.cc
@@ -6,6 +6,7 @@
 #include "memory_tracker-inl.h"
 #include "node_buffer.h"
 #include "node_context_data.h"
+#include "node_contextify.h"
 #include "node_errors.h"
 #include "node_internals.h"
 #include "node_options-inl.h"
@@ -444,6 +445,8 @@ void IsolateData::CreateProperties() {
 #undef V
 
   // TODO(legendecas): eagerly create per isolate templates.
+  set_contextify_global_template(
+      contextify::ContextifyContext::CreateGlobalTemplate(isolate_));
 }
 
 IsolateData::IsolateData(Isolate* isolate,
@@ -512,13 +515,19 @@ void TrackingTraceStateObserver::UpdateTraceCategoryState() {
 
 void Environment::AssignToContext(Local<v8::Context> context,
                                   const ContextInfo& info) {
-  ContextEmbedderTag::TagNodeContext(context);
   context->SetAlignedPointerInEmbedderData(ContextEmbedderIndex::kEnvironment,
                                            this);
   // Used to retrieve bindings
   context->SetAlignedPointerInEmbedderData(
       ContextEmbedderIndex::kBindingListIndex, &(this->bindings_));
 
+  // ContextifyContexts will update this to a pointer to the native object.
+  context->SetAlignedPointerInEmbedderData(
+      ContextEmbedderIndex::kContextifyContext, nullptr);
+
+  // This must not be done before other context fields are initialized.
+  ContextEmbedderTag::TagNodeContext(context);
+
 #if HAVE_INSPECTOR
   inspector_agent()->ContextCreated(context, info);
 #endif  // HAVE_INSPECTOR
@@ -769,6 +778,8 @@ void Environment::InitializeMainContext(Local<Context> context,
                                         const EnvSerializeInfo* env_info) {
   context_.Reset(context->GetIsolate(), context);
   AssignToContext(context, ContextInfo(""));
+  context->SetAlignedPointerInEmbedderData(
+      ContextEmbedderIndex::kContextifyContext, nullptr);
   if (env_info != nullptr) {
     DeserializeProperties(env_info);
   } else {

diff --git a/src/env.h b/src/env.h
@@ -349,6 +349,7 @@ class NoArrayBufferZeroFillScope {
   V(nistcurve_string, "nistCurve")                                             \
   V(node_string, "node")                                                       \
   V(nsname_string, "nsname")                                                   \
+  V(object_string, "Object")                                                   \
   V(ocsp_request_string, "OCSPRequest")                                        \
   V(oncertcb_string, "oncertcb")                                               \
   V(onchange_string, "onchange")                                               \
@@ -477,6 +478,7 @@ class NoArrayBufferZeroFillScope {
   V(binding_data_ctor_template, v8::FunctionTemplate)                          \
   V(blob_constructor_template, v8::FunctionTemplate)                           \
   V(blocklist_constructor_template, v8::FunctionTemplate)                      \
+  V(contextify_global_template, v8::ObjectTemplate)                            \
   V(compiled_fn_entry_template, v8::ObjectTemplate)                            \
   V(dir_instance_template, v8::ObjectTemplate)                                 \
   V(fd_constructor_template, v8::ObjectTemplate)                               \
@@ -560,7 +562,6 @@ class NoArrayBufferZeroFillScope {
   V(primordials_safe_weak_set_prototype_object, v8::Object)                    \
   V(promise_hook_handler, v8::Function)                                        \
   V(promise_reject_callback, v8::Function)                                     \
-  V(script_data_constructor_function, v8::Function)                            \
   V(snapshot_serialize_callback, v8::Function)                                 \
   V(snapshot_deserialize_callback, v8::Function)                               \
   V(snapshot_deserialize_main, v8::Function)                                   \

diff --git a/src/node_context_data.h b/src/node_context_data.h
@@ -29,11 +29,15 @@ namespace node {
 #define NODE_CONTEXT_ALLOW_CODE_GENERATION_FROM_STRINGS_INDEX 36
 #endif
 
+#ifndef NODE_CONTEXT_CONTEXTIFY_CONTEXT_INDEX
+#define NODE_CONTEXT_CONTEXTIFY_CONTEXT_INDEX 37
+#endif
+
 // NODE_CONTEXT_TAG must be greater than any embedder indexes so that a single
 // check on the number of embedder data fields can assure the presence of all
 // embedder indexes.
 #ifndef NODE_CONTEXT_TAG
-#define NODE_CONTEXT_TAG 37
+#define NODE_CONTEXT_TAG 38
 #endif
 
 enum ContextEmbedderIndex {
@@ -43,6 +47,7 @@ enum ContextEmbedderIndex {
   kBindingListIndex = NODE_BINDING_LIST_INDEX,
   kAllowCodeGenerationFromStrings =
       NODE_CONTEXT_ALLOW_CODE_GENERATION_FROM_STRINGS_INDEX,
+  kContextifyContext = NODE_CONTEXT_CONTEXTIFY_CONTEXT_INDEX,
   kContextTag = NODE_CONTEXT_TAG,
 };