[ReactNative] Add JSC profiler to Dev Menu

Summary:
Add JSC profiler to the dev menu and rename the pre-existent one to systrace.

For now it just outputs to the console, but a better workflow is on the way.

JSCLegacyProfiler/JSCLegacyProfiler.h

@@ -6,20 +6,7 @@
 
 extern "C" {
 
-JSValueRef nativeProfilerStart(
-    JSContextRef ctx,
-    JSObjectRef function,
-    JSObjectRef thisObject,
-    size_t argumentCount,
-    const JSValueRef arguments[],
-    JSValueRef *exception);
-
-JSValueRef nativeProfilerEnd(
-    JSContextRef ctx,
-    JSObjectRef function,
-    JSObjectRef thisObject,
-    size_t argumentCount,
-    const JSValueRef arguments[],
-    JSValueRef *exception);
+void nativeProfilerStart(JSContextRef ctx, const char *title);
+const char *nativeProfilerEnd(JSContextRef ctx, const char *title);
 
 }

JSCLegacyProfiler/JSCLegacyProfiler.mm

@@ -7,6 +7,7 @@
 #include "OpaqueJSString.h"
 #include "JSProfilerPrivate.h"
 #include "JSStringRef.h"
+#include "String.h"
 
 #include <YAJL/yajl_gen.h>
 
@@ -114,48 +115,18 @@ static char *convert_to_json(const JSC::Profile *profile) {
   return json_copy;
 }
 
-static char *JSEndProfilingAndRender(JSContextRef ctx, JSStringRef title)
+static const char *JSEndProfilingAndRender(JSContextRef ctx, const char *title)
 {
     JSC::ExecState *exec = toJS(ctx);
     JSC::LegacyProfiler *profiler = JSC::LegacyProfiler::profiler();
-    RefPtr<JSC::Profile> rawProfile = profiler->stopProfiling(exec, title->string());
+    RefPtr<JSC::Profile> rawProfile = profiler->stopProfiling(exec, WTF::String(title));
     return convert_to_json(rawProfile.get());
 }
 
-JSValueRef nativeProfilerStart(
-    JSContextRef ctx,
-    JSObjectRef function,
-    JSObjectRef thisObject,
-    size_t argumentCount,
-    const JSValueRef arguments[],
-    JSValueRef *exception) {
-  if (argumentCount < 1) {
-    // Could raise an exception here.
-    return JSValueMakeUndefined(ctx);
-  }
-
-  JSStringRef title = JSValueToStringCopy(ctx, arguments[0], NULL);
-  JSStartProfiling(ctx, title);
-  JSStringRelease(title);
-  return JSValueMakeUndefined(ctx);
+void nativeProfilerStart(JSContextRef ctx, const char *title) {
+  JSStartProfiling(ctx, JSStringCreateWithUTF8CString(title));
 }
 
-JSValueRef nativeProfilerEnd(
-    JSContextRef ctx,
-    JSObjectRef function,
-    JSObjectRef thisObject,
-    size_t argumentCount,
-    const JSValueRef arguments[],
-    JSValueRef *exception) {
-  if (argumentCount < 1) {
-    // Could raise an exception here.
-    return JSValueMakeUndefined(ctx);
-  }
-
-  JSStringRef title = JSValueToStringCopy(ctx, arguments[0], NULL);
-  char *rendered = JSEndProfilingAndRender(ctx, title);
-  JSStringRelease(title);
-  JSStringRef profile = JSStringCreateWithUTF8CString(rendered);
-  free(rendered);
-  return JSValueMakeString(ctx, profile);
+const char *nativeProfilerEnd( JSContextRef ctx, const char *title) {
+  return JSEndProfilingAndRender(ctx, title);
 }

JSCLegacyProfiler/Makefile

@@ -110,5 +110,3 @@ armv7:
 		${HEADER_PATHS} \
 		-undefined dynamic_lookup \
 		./JSCLegacyProfiler.mm ./tmp/yajl.a
-
-.PHONY: ios8

React/Executors/RCTContextExecutor.m

@@ -16,6 +16,7 @@
 
 #import "RCTAssert.h"
 #import "RCTDefines.h"
+#import "RCTDevMenu.h"
 #import "RCTLog.h"
 #import "RCTProfile.h"
 #import "RCTPerformanceLogger.h"
@@ -89,6 +90,7 @@ RCT_NOT_IMPLEMENTED(-(instancetype)init)
 }
 
 @synthesize valid = _valid;
+@synthesize bridge = _bridge;
 
 RCT_EXPORT_MODULE()
 
@@ -285,11 +287,18 @@ static JSValueRef RCTNativeTraceEndSection(JSContextRef context, __unused JSObje
 #if RCT_JSC_PROFILER
     void *JSCProfiler = dlopen(RCT_JSC_PROFILER_DYLIB, RTLD_NOW);
     if (JSCProfiler != NULL) {
-      JSObjectCallAsFunctionCallback nativeProfilerStart = dlsym(JSCProfiler, "nativeProfilerStart");
-      JSObjectCallAsFunctionCallback nativeProfilerEnd = dlsym(JSCProfiler, "nativeProfilerEnd");
+      void (*nativeProfilerStart)(JSContextRef, const char *) = (void (*)(JSContextRef, const char *))dlsym(JSCProfiler, "nativeProfilerStart");
+      const char *(*nativeProfilerEnd)(JSContextRef, const char *) = (const char *(*)(JSContextRef, const char *))dlsym(JSCProfiler, "nativeProfilerEnd");
       if (nativeProfilerStart != NULL && nativeProfilerEnd != NULL) {
-        [strongSelf _addNativeHook:nativeProfilerStart withName:"nativeProfilerStart"];
-        [strongSelf _addNativeHook:nativeProfilerEnd withName:"nativeProfilerStop"];
+        __block BOOL isProfiling = NO;
+        [_bridge.devMenu addItem:@"Profile" handler:^{
+          if (isProfiling) {
+            RCTLogInfo(@"%s", nativeProfilerEnd(strongSelf->_context.ctx, "profile"));
+          } else {
+            nativeProfilerStart(strongSelf->_context.ctx, "profile");
+          }
+          isProfiling = !isProfiling;
+        }];
       }
     }
 #endif

React/Modules/RCTDevMenu.m

@@ -314,7 +314,7 @@ RCT_EXPORT_MODULE()
       self.liveReloadEnabled = !_liveReloadEnabled;
     }]];
 
-    NSString *profilingTitle  = RCTProfileIsProfiling() ? @"Stop Profiling" : @"Start Profiling";
+    NSString *profilingTitle  = RCTProfileIsProfiling() ? @"Stop Systrace" : @"Start Systrace";
     [items addObject:[[RCTDevMenuItem alloc] initWithTitle:profilingTitle handler:^{
       self.profilingEnabled = !_profilingEnabled;
     }]];