ScriptController: Expose methods to compile a script and execute a compiled script.

third_party/WebKit/Source/bindings/core/v8/ScriptController.cpp

Index: third_party/WebKit/Source/bindings/core/v8/ScriptController.cpp
diff --git a/third_party/WebKit/Source/bindings/core/v8/ScriptController.cpp b/third_party/WebKit/Source/bindings/core/v8/ScriptController.cpp
index d6d58c058eb92b026696323618b1204c090df3ac..a8ab942a5d98d7afe42822de60cf834b67e032c0 100644
--- a/third_party/WebKit/Source/bindings/core/v8/ScriptController.cpp
+++ b/third_party/WebKit/Source/bindings/core/v8/ScriptController.cpp
@@ -32,6 +32,7 @@
 
 #include "bindings/core/v8/ScriptController.h"
 
+#include "bindings/core/v8/CompiledScript.h"
 #include "bindings/core/v8/ScriptSourceCode.h"
 #include "bindings/core/v8/ScriptValue.h"
 #include "bindings/core/v8/V8Binding.h"
@@ -93,6 +94,32 @@ void ScriptController::updateSecurityOrigin(SecurityOrigin* securityOrigin) {
   m_windowProxyManager->updateSecurityOrigin(securityOrigin);
 }
 
+namespace {
+
+V8CacheOptions cacheOptions(const ScriptResource* resource,
+                            const Settings* settings) {
+  V8CacheOptions v8CacheOptions(V8CacheOptionsDefault);
+  if (settings)
+    v8CacheOptions = settings->v8CacheOptions();
+  if (resource && !resource->response().cacheStorageCacheName().isNull()) {
+    switch (settings->v8CacheStrategiesForCacheStorage()) {
+      case V8CacheStrategiesForCacheStorage::None:
+        v8CacheOptions = V8CacheOptionsNone;
+        break;
+      case V8CacheStrategiesForCacheStorage::Normal:
+        v8CacheOptions = V8CacheOptionsCode;
+        break;
+      case V8CacheStrategiesForCacheStorage::Default:
+      case V8CacheStrategiesForCacheStorage::Aggressive:
+        v8CacheOptions = V8CacheOptionsAlways;
+        break;
+    }
+  }
+  return v8CacheOptions;
+}
+
+}  // namespace
+
 v8::Local<v8::Value> ScriptController::executeScriptAndReturnValue(
     v8::Local<v8::Context> context,
     const ScriptSourceCode& source,
@@ -105,24 +132,8 @@ v8::Local<v8::Value> ScriptController::executeScriptAndReturnValue(
 
   v8::Local<v8::Value> result;
   {
-    V8CacheOptions v8CacheOptions(V8CacheOptionsDefault);
-    if (frame()->settings())
-      v8CacheOptions = frame()->settings()->v8CacheOptions();
-    if (source.resource() &&
-        !source.resource()->response().cacheStorageCacheName().isNull()) {
-      switch (frame()->settings()->v8CacheStrategiesForCacheStorage()) {
-        case V8CacheStrategiesForCacheStorage::None:
-          v8CacheOptions = V8CacheOptionsNone;
-          break;
-        case V8CacheStrategiesForCacheStorage::Normal:
-          v8CacheOptions = V8CacheOptionsCode;
-          break;
-        case V8CacheStrategiesForCacheStorage::Default:
-        case V8CacheStrategiesForCacheStorage::Aggressive:
-          v8CacheOptions = V8CacheOptionsAlways;
-          break;
-      }
-    }
+    V8CacheOptions v8CacheOptions =
+        cacheOptions(source.resource(), frame()->settings());
 
     // Isolate exceptions that occur when compiling and executing
     // the code. These exceptions should not interfere with
@@ -150,6 +161,54 @@ v8::Local<v8::Value> ScriptController::executeScriptAndReturnValue(
   return result;
 }
 
+CompiledScript* ScriptController::compileScriptInMainWorld(
+    const ScriptSourceCode& source,
+    AccessControlStatus accessControlStatus) {
+  V8CacheOptions v8CacheOptions =
+      cacheOptions(source.resource(), frame()->settings());
+
+  v8::HandleScope handleScope(isolate());
+  v8::TryCatch tryCatch(isolate());
+  tryCatch.SetVerbose(true);
+
+  v8::Local<v8::Script> script;
+  if (!v8Call(V8ScriptRunner::compileScript(
+                  source, isolate(), accessControlStatus, v8CacheOptions),
+              script, tryCatch)) {
+    return nullptr;
+  }
+
+  TRACE_EVENT_INSTANT1(TRACE_DISABLED_BY_DEFAULT("devtools.timeline"),
+                       "UpdateCounters", TRACE_EVENT_SCOPE_THREAD, "data",
+                       InspectorUpdateCountersEvent::data());
+  return new CompiledScript(isolate(), script, source);
+}
+
+void ScriptController::executeScriptInMainWorld(
+    const CompiledScript& compiledScript) {
+  TRACE_EVENT1("devtools.timeline", "EvaluateScript", "data",
+               InspectorEvaluateScriptEvent::data(
+                   frame(), compiledScript.url().getString(),
+                   compiledScript.startPosition()));

[haraken, 2016/12/12 00:53:57]

Shall we introduce two trace events: "CompileScript" and "RunScript"?

- compileScript uses "CompileScript"
- executeScript uses "RunScript"
- executeScriptAndReturnValue uses "CompileScript" and "RunScript"

[jbroman, 2016/12/13 15:53:21]

I'm not opposed in principle, but these string constants are written into the
devtools timeline model code. It does already have a compile event, triggering
off "v8.compile" (which, along with "v8.run", already exists in V8ScriptRunner).
I admit to not being entirely sure why we have this separate event given that
v8.compile and v8.run both exist in the devtools.timeline category.

+  InspectorInstrumentation::NativeBreakpoint nativeBreakpoint(
+      frame()->document(), "scriptFirstStatement", false);
+
+  v8::HandleScope handleScope(isolate());
+  v8::TryCatch tryCatch(isolate());
+  tryCatch.SetVerbose(true);
+
+  v8::Local<v8::Value> result;
+  if (!v8Call(
+          V8ScriptRunner::runCompiledScript(
+              isolate(), compiledScript.script(isolate()), frame()->document()),
+          result, tryCatch))
+    return;
+
+  TRACE_EVENT_INSTANT1(TRACE_DISABLED_BY_DEFAULT("devtools.timeline"),
+                       "UpdateCounters", TRACE_EVENT_SCOPE_THREAD, "data",
+                       InspectorUpdateCountersEvent::data());

[haraken, 2016/12/12 00:53:57]

I don't fully understand this trace event. Is it expected to be called on both
compileScript and executeScript? Before this CL, it was called only once for
each compile & execution step.

[jbroman, 2016/12/13 15:53:21]

From what I can tell, it makes a note of the heap size, JS listener count,
document and node count. Since the script compile may increase the heap size
(and execution certainly can), it seems reasonable to update these in the
devtools timeline at both times.

+}
+
 bool ScriptController::initializeMainWorld() {
   if (m_windowProxyManager->mainWorldProxy()->isContextInitialized())
     return false;