perf: use v8::Local<v8::Object> as the key in ObjectCache (#43519)

* perf: use v8::Object* as direct keys instead of using hash + a linked list

* refactor: use v8::Local<v8::Object> as the key
This commit is contained in:
Charles Kerr 2024-09-04 22:53:06 -05:00 committed by GitHub
parent 0467790aee
commit 2d868ecb8d
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GPG key ID: B5690EEEBB952194
2 changed files with 25 additions and 34 deletions

View file

@ -12,37 +12,22 @@ namespace electron::api::context_bridge {
ObjectCache::ObjectCache() = default;
ObjectCache::~ObjectCache() = default;
void ObjectCache::CacheProxiedObject(v8::Local<v8::Value> from,
void ObjectCache::CacheProxiedObject(const v8::Local<v8::Value> from,
v8::Local<v8::Value> proxy_value) {
if (from->IsObject() && !from->IsNullOrUndefined()) {
auto obj = from.As<v8::Object>();
int hash = obj->GetIdentityHash();
proxy_map_[hash].emplace_front(from, proxy_value);
}
if (from->IsObject() && !from->IsNullOrUndefined())
proxy_map_.insert_or_assign(from.As<v8::Object>(), proxy_value);
}
v8::MaybeLocal<v8::Value> ObjectCache::GetCachedProxiedObject(
v8::Local<v8::Value> from) const {
const v8::Local<v8::Value> from) const {
if (!from->IsObject() || from->IsNullOrUndefined())
return v8::MaybeLocal<v8::Value>();
return {};
auto obj = from.As<v8::Object>();
int hash = obj->GetIdentityHash();
auto iter = proxy_map_.find(hash);
if (iter == proxy_map_.end())
return v8::MaybeLocal<v8::Value>();
const auto iter = proxy_map_.find(from.As<v8::Object>());
if (iter == proxy_map_.end() || iter->second.IsEmpty())
return {};
auto& list = iter->second;
for (const auto& pair : list) {
auto from_cmp = pair.first;
if (from_cmp == from) {
if (pair.second.IsEmpty())
return v8::MaybeLocal<v8::Value>();
return pair.second;
}
}
return v8::MaybeLocal<v8::Value>();
return iter->second;
}
} // namespace electron::api::context_bridge

View file

@ -5,19 +5,18 @@
#ifndef ELECTRON_SHELL_RENDERER_API_CONTEXT_BRIDGE_OBJECT_CACHE_H_
#define ELECTRON_SHELL_RENDERER_API_CONTEXT_BRIDGE_OBJECT_CACHE_H_
#include <forward_list>
#include <unordered_map>
#include <utility>
#include "content/public/renderer/render_frame.h"
#include "content/public/renderer/render_frame_observer.h"
#include "shell/renderer/electron_render_frame_observer.h"
#include "third_party/blink/public/web/web_local_frame.h"
#include "v8/include/v8-local-handle.h"
#include "v8/include/v8-object.h"
namespace electron::api::context_bridge {
using ObjectCachePair = std::pair<v8::Local<v8::Value>, v8::Local<v8::Value>>;
/**
* NB: This is designed for context_bridge. Beware using it elsewhere!
* Since it's a v8::Local-to-v8::Local cache, be careful to destroy it
* before destroying the HandleScope that keeps the locals alive.
*/
class ObjectCache final {
public:
ObjectCache();
@ -29,8 +28,15 @@ class ObjectCache final {
v8::Local<v8::Value> from) const;
private:
// object_identity ==> [from_value, proxy_value]
std::unordered_map<int, std::forward_list<ObjectCachePair>> proxy_map_;
struct Hash {
std::size_t operator()(const v8::Local<v8::Object>& obj) const {
return obj->GetIdentityHash();
}
};
// from_object ==> proxy_value
std::unordered_map<v8::Local<v8::Object>, v8::Local<v8::Value>, Hash>
proxy_map_;
};
} // namespace electron::api::context_bridge