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.

PR-URL: #44252
Refs: #44014
Refs: #37476
Reviewed-By: Chengzhong Wu <legendecas@gmail.com>

Author: joyeecheung

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"
@@ -429,6 +430,8 @@ void IsolateData::CreateProperties() {
 #undef V
 
   // TODO(legendecas): eagerly create per isolate templates.
+  set_contextify_global_template(
+      contextify::ContextifyContext::CreateGlobalTemplate(isolate_));
 }
 
 IsolateData::IsolateData(Isolate* isolate,
@@ -497,13 +500,19 @@ 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

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)                                   \

src/node_context_data.h

@@ -32,11 +32,15 @@ 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 {
@@ -46,6 +50,7 @@ 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,
 };