src: refactor v8 binding

1. Put the v8 binding data class into a header so we can reuse
  the class definition during deserialization.
2. Put the v8 binding code into node::v8_utils namespace for
  clarity.
3. Move the binding data property initialization into its
  constructor so that we can reuse it during deserialization
4. Reorder the v8 binding initialization so that we don't
  unnecessarily initialize the properties in a loop

PR-URL: https://github.com/nodejs/node/pull/37112
Refs: https://github.com/nodejs/node/pull/36943
Reviewed-By: Juan José Arboleda <soyjuanarbol@gmail.com>

2 files changed, 76 insertions, 60 deletions

diff --git a/src/node_v8.cc b/src/node_v8.cc
index d66b5e03b86..4354e1e1772 100644
--- a/src/node_v8.cc
+++ b/src/node_v8.cc
@@ -19,15 +19,16 @@
 // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 // USE OR OTHER DEALINGS IN THE SOFTWARE.
 
-#include "node.h"
+#include "node_v8.h"
 #include "base_object-inl.h"
 #include "env-inl.h"
 #include "memory_tracker-inl.h"
+#include "node.h"
 #include "util-inl.h"
 #include "v8.h"
 
 namespace node {
-
+namespace v8_utils {
 using v8::Array;
 using v8::Context;
 using v8::FunctionCallbackInfo;
@@ -44,7 +45,6 @@ using v8::Uint32;
 using v8::V8;
 using v8::Value;
 
-
 #define HEAP_STATISTICS_PROPERTIES(V)                                         \
   V(0, total_heap_size, kTotalHeapSizeIndex)                                  \
   V(1, total_heap_size_executable, kTotalHeapSizeExecutableIndex)             \
@@ -63,7 +63,6 @@ static constexpr size_t kHeapStatisticsPropertiesCount =
     HEAP_STATISTICS_PROPERTIES(V);
 #undef V
 
-
 #define HEAP_SPACE_STATISTICS_PROPERTIES(V)                                   \
   V(0, space_size, kSpaceSizeIndex)                                           \
   V(1, space_used_size, kSpaceUsedSizeIndex)                                  \
@@ -85,32 +84,34 @@ static const size_t kHeapCodeStatisticsPropertiesCount =
     HEAP_CODE_STATISTICS_PROPERTIES(V);
 #undef V
 
-class BindingData : public BaseObject {
- public:
-  BindingData(Environment* env, Local<Object> obj)
-      : BaseObject(env, obj),
-        heap_statistics_buffer(env->isolate(), kHeapStatisticsPropertiesCount),
-        heap_space_statistics_buffer(env->isolate(),
-                                     kHeapSpaceStatisticsPropertiesCount),
-        heap_code_statistics_buffer(env->isolate(),
-                                    kHeapCodeStatisticsPropertiesCount) {}
-
-  static constexpr FastStringKey type_name { "v8" };
-
-  AliasedFloat64Array heap_statistics_buffer;
-  AliasedFloat64Array heap_space_statistics_buffer;
-  AliasedFloat64Array heap_code_statistics_buffer;
-
-  void MemoryInfo(MemoryTracker* tracker) const override {
-    tracker->TrackField("heap_statistics_buffer", heap_statistics_buffer);
-    tracker->TrackField("heap_space_statistics_buffer",
-                        heap_space_statistics_buffer);
-    tracker->TrackField("heap_code_statistics_buffer",
-                        heap_code_statistics_buffer);
-  }
-  SET_SELF_SIZE(BindingData)
-  SET_MEMORY_INFO_NAME(BindingData)
-};
+BindingData::BindingData(Environment* env, Local<Object> obj)
+    : BaseObject(env, obj),
+      heap_statistics_buffer(env->isolate(), kHeapStatisticsPropertiesCount),
+      heap_space_statistics_buffer(env->isolate(),
+                                   kHeapSpaceStatisticsPropertiesCount),
+      heap_code_statistics_buffer(env->isolate(),
+                                  kHeapCodeStatisticsPropertiesCount) {
+  obj->Set(env->context(),
+           FIXED_ONE_BYTE_STRING(env->isolate(), "heapStatisticsBuffer"),
+           heap_statistics_buffer.GetJSArray())
+      .Check();
+  obj->Set(env->context(),
+           FIXED_ONE_BYTE_STRING(env->isolate(), "heapCodeStatisticsBuffer"),
+           heap_code_statistics_buffer.GetJSArray())
+      .Check();
+  obj->Set(env->context(),
+           FIXED_ONE_BYTE_STRING(env->isolate(), "heapSpaceStatisticsBuffer"),
+           heap_space_statistics_buffer.GetJSArray())
+      .Check();
+}
+
+void BindingData::MemoryInfo(MemoryTracker* tracker) const {
+  tracker->TrackField("heap_statistics_buffer", heap_statistics_buffer);
+  tracker->TrackField("heap_space_statistics_buffer",
+                      heap_space_statistics_buffer);
+  tracker->TrackField("heap_code_statistics_buffer",
+                      heap_code_statistics_buffer);
+}
 
 // TODO(addaleax): Remove once we're on C++17.
 constexpr FastStringKey BindingData::type_name;
@@ -179,36 +180,12 @@ void Initialize(Local<Object> target,
 
   env->SetMethodNoSideEffect(target, "cachedDataVersionTag",
                              CachedDataVersionTag);
-
-  // Export symbols used by v8.getHeapStatistics()
   env->SetMethod(
       target, "updateHeapStatisticsBuffer", UpdateHeapStatisticsBuffer);
 
-  target
-      ->Set(env->context(),
-            FIXED_ONE_BYTE_STRING(env->isolate(), "heapStatisticsBuffer"),
-            binding_data->heap_statistics_buffer.GetJSArray())
-      .Check();
-
-#define V(i, _, name)                                                         \
-  target->Set(env->context(),                                                 \
-              FIXED_ONE_BYTE_STRING(env->isolate(), #name),                   \
-              Uint32::NewFromUnsigned(env->isolate(), i)).Check();
-
-  HEAP_STATISTICS_PROPERTIES(V)
-
-  // Export symbols used by v8.getHeapCodeStatistics()
   env->SetMethod(
       target, "updateHeapCodeStatisticsBuffer", UpdateHeapCodeStatisticsBuffer);
 
-  target
-      ->Set(env->context(),
-            FIXED_ONE_BYTE_STRING(env->isolate(), "heapCodeStatisticsBuffer"),
-            binding_data->heap_code_statistics_buffer.GetJSArray())
-      .Check();
-
-  HEAP_CODE_STATISTICS_PROPERTIES(V)
-
   size_t number_of_heap_spaces = env->isolate()->NumberOfHeapSpaces();
 
   // Heap space names are extracted once and exposed to JavaScript to
@@ -230,13 +207,15 @@ void Initialize(Local<Object> target,
                  "updateHeapSpaceStatisticsBuffer",
                  UpdateHeapSpaceStatisticsBuffer);
 
-  target
-      ->Set(env->context(),
-            FIXED_ONE_BYTE_STRING(env->isolate(),
-                                  "heapSpaceStatisticsBuffer"),
-            binding_data->heap_space_statistics_buffer.GetJSArray())
+#define V(i, _, name)                                                          \
+  target                                                                       \
+      ->Set(env->context(),                                                    \
+            FIXED_ONE_BYTE_STRING(env->isolate(), #name),                      \
+            Uint32::NewFromUnsigned(env->isolate(), i))                        \
       .Check();
 
+  HEAP_STATISTICS_PROPERTIES(V)
+  HEAP_CODE_STATISTICS_PROPERTIES(V)
   HEAP_SPACE_STATISTICS_PROPERTIES(V)
 #undef V
 
@@ -244,6 +223,7 @@ void Initialize(Local<Object> target,
   env->SetMethod(target, "setFlagsFromString", SetFlagsFromString);
 }
 
+}  // namespace v8_utils
 }  // namespace node
 
-NODE_MODULE_CONTEXT_AWARE_INTERNAL(v8, node::Initialize)
+NODE_MODULE_CONTEXT_AWARE_INTERNAL(v8, node::v8_utils::Initialize)
diff --git a/src/node_v8.h b/src/node_v8.h
new file mode 100644
index 00000000000..745c6580b84
--- /dev/null
+++ b/src/node_v8.h
@@ -0,0 +1,36 @@
+#ifndef SRC_NODE_V8_H_
+#define SRC_NODE_V8_H_
+
+#if defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS
+
+#include "aliased_buffer.h"
+#include "base_object.h"
+#include "util.h"
+#include "v8.h"
+
+namespace node {
+class Environment;
+
+namespace v8_utils {
+class BindingData : public BaseObject {
+ public:
+  BindingData(Environment* env, v8::Local<v8::Object> obj);
+
+  static constexpr FastStringKey type_name{"node::v8::BindingData"};
+
+  AliasedFloat64Array heap_statistics_buffer;
+  AliasedFloat64Array heap_space_statistics_buffer;
+  AliasedFloat64Array heap_code_statistics_buffer;
+
+  void MemoryInfo(MemoryTracker* tracker) const override;
+  SET_SELF_SIZE(BindingData)
+  SET_MEMORY_INFO_NAME(BindingData)
+};
+
+}  // namespace v8_utils
+
+}  // namespace node
+
+#endif  // defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS
+
+#endif  // SRC_NODE_V8_H_