introduce native api to access RuntimeExecutor

packages/react-native/React/Base/RCTRuntimeExecutorModule.h

@@ -0,0 +1,18 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+@class RCTRuntimeExecutor;
+
+/**
+ * Have your module conform to this protocol to access the RuntimeExecutor.
+ * Only available in the bridgeless runtime.
+ */
+@protocol RCTRuntimeExecutorModule <NSObject>
+
+@property (nonatomic, nullable, readwrite) RCTRuntimeExecutor *runtimeExecutor;
+
+@end

packages/react-native/ReactCommon/react/nativemodule/core/platform/ios/ReactCommon/RCTRuntimeExecutor.h

@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#import <ReactCommon/RuntimeExecutor.h>
+#import <jsi/jsi.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+typedef void (^RCTJSIRuntimeHandlingBlock)(facebook::jsi::Runtime &runtime);
+
+@interface RCTRuntimeExecutor : NSObject
+
+- (instancetype)init NS_UNAVAILABLE;
+
+/**
+ Initializes an object that wraps ways to access the RuntimeExecutor.
+
+ @param runtimeExecutor The instance of RuntimeExecutor.
+ */
+- (instancetype)initWithRuntimeExecutor:(facebook::react::RuntimeExecutor)runtimeExecutor NS_DESIGNATED_INITIALIZER;
+
+- (void)execute:(RCTJSIRuntimeHandlingBlock)block;
+
+@end
+
+NS_ASSUME_NONNULL_END

packages/react-native/ReactCommon/react/nativemodule/core/platform/ios/ReactCommon/RCTRuntimeExecutor.mm

@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#import "RCTRuntimeExecutor.h"
+
+@implementation RCTRuntimeExecutor {
+  facebook::react::RuntimeExecutor _runtimeExecutor;
+}
+
+#pragma mark - Initializer
+
+- (instancetype)initWithRuntimeExecutor:(facebook::react::RuntimeExecutor)runtimeExecutor
+{
+  if (self = [super init]) {
+    _runtimeExecutor = runtimeExecutor;
+  }
+
+  return self;
+}
+
+#pragma mark - Public API
+
+- (void)execute:(RCTJSIRuntimeHandlingBlock)block
+{
+  if (_runtimeExecutor) {
+    _runtimeExecutor([=](facebook::jsi::Runtime &runtime) { block(runtime); });
+  }
+}
+
+@end

packages/react-native/ReactCommon/react/nativemodule/core/platform/ios/ReactCommon/RCTTurboModuleManager.h

@@ -15,8 +15,11 @@
 #import <React/RCTTurboModuleRegistry.h>
 #import <ReactCommon/RuntimeExecutor.h>
 #import <ReactCommon/TurboModuleBinding.h>
+
 #import "RCTTurboModule.h"
 
+@class RCTTurboModuleManager;
+
 @protocol RCTTurboModuleManagerDelegate <NSObject>
 
 /**
@@ -52,6 +55,12 @@
 
 @end
 
+@protocol RCTTurboModuleManagerRuntimeHandler <NSObject>
+
+- (facebook::react::RuntimeExecutor)runtimeExecutorForTurboModuleManager:(RCTTurboModuleManager *)turboModuleManager;
+
+@end
+
 @interface RCTTurboModuleManager : NSObject <RCTTurboModuleRegistry>
 
 - (instancetype)initWithBridge:(RCTBridge *)bridge
@@ -67,4 +76,6 @@
 
 - (void)invalidate;
 
+@property (nonatomic, weak, readwrite) id<RCTTurboModuleManagerRuntimeHandler> runtimeHandler;
+
 @end

packages/react-native/ReactCommon/react/nativemodule/core/platform/ios/ReactCommon/RCTTurboModuleManager.mm

@@ -7,6 +7,7 @@
 
 #import "RCTTurboModuleManager.h"
 #import "RCTInteropTurboModule.h"
+#import "RCTRuntimeExecutor.h"
 
 #import <atomic>
 #import <cassert>
@@ -24,8 +25,8 @@
 #import <React/RCTLog.h>
 #import <React/RCTModuleData.h>
 #import <React/RCTPerformanceLogger.h>
+#import <React/RCTRuntimeExecutorModule.h>
 #import <React/RCTUtils.h>
-#import <ReactCommon/RuntimeExecutor.h>
 #import <ReactCommon/TurboCxxModule.h>
 #import <ReactCommon/TurboModulePerfLogger.h>
 #import <ReactCommon/TurboModuleUtils.h>
@@ -676,6 +677,13 @@ - (BOOL)_shouldCreateObjCModule:(Class)moduleClass
     }
   }
 
+  // This is a more performant alternative for conformsToProtocol:@protocol(RCTRuntimeExecutorModule)
+  if ([module respondsToSelector:@selector(setRuntimeExecutor:)]) {
+    RCTRuntimeExecutor *runtimeExecutor = [[RCTRuntimeExecutor alloc]
+        initWithRuntimeExecutor:[_runtimeHandler runtimeExecutorForTurboModuleManager:self]];
+    [(id<RCTRuntimeExecutorModule>)module setRuntimeExecutor:runtimeExecutor];
+  }
+
   /**
    * Some modules need their own queues, but don't provide any, so we need to create it for them.
    * These modules typically have the following:

packages/react-native/ReactCommon/react/runtime/platform/ios/ReactCommon/RCTInstance.mm

@@ -63,7 +63,7 @@ void RCTInstanceSetRuntimeDiagnosticFlags(NSString *flags)
   sRuntimeDiagnosticFlags = [flags copy];
 }
 
-@interface RCTInstance () <RCTTurboModuleManagerDelegate>
+@interface RCTInstance () <RCTTurboModuleManagerDelegate, RCTTurboModuleManagerRuntimeHandler>
 @end
 
 @implementation RCTInstance {
@@ -208,6 +208,17 @@ - (Class)getModuleClassFromName:(const char *)name
   return nullptr;
 }
 
+#pragma mark - RCTTurboModuleManagerRuntimeHandler
+
+- (RuntimeExecutor)runtimeExecutorForTurboModuleManager:(RCTTurboModuleManager *)turboModuleManager
+{
+  if (_valid) {
+    return _reactInstance->getBufferedRuntimeExecutor();
+  }
+
+  return nullptr;
+}
+
 #pragma mark - Private
 
 - (void)_start
@@ -259,6 +270,7 @@ - (void)_start
       bridgeModuleDecorator:_bridgeModuleDecorator
                    delegate:self
                   jsInvoker:std::make_shared<BridgelessJSCallInvoker>(bufferedRuntimeExecutor)];
+  _turboModuleManager.runtimeHandler = self;
 
 #if RCT_DEV
   /**