Moved text decoding to the parser thread

Source/core/html/parser/HTMLDocumentParser.cpp

Index: Source/core/html/parser/HTMLDocumentParser.cpp
diff --git a/Source/core/html/parser/HTMLDocumentParser.cpp b/Source/core/html/parser/HTMLDocumentParser.cpp
index f3a7f49f75121a265fcd27f833d2356e1963e752..5b95cbb4d237bf43af0849ae5b4a032f2ce8aa54 100644
--- a/Source/core/html/parser/HTMLDocumentParser.cpp
+++ b/Source/core/html/parser/HTMLDocumentParser.cpp
@@ -42,6 +42,7 @@
 #include "core/html/parser/HTMLTreeBuilder.h"
 #include "core/inspector/InspectorInstrumentation.h"
 #include "core/frame/Frame.h"
+#include "platform/SharedBuffer.h"
 #include "platform/TraceEvent.h"
 #include "wtf/Functional.h"
 
@@ -319,6 +320,10 @@ void HTMLDocumentParser::didReceiveParsedChunkFromBackgroundParser(PassOwnPtr<Pa
     m_speculations.append(chunk);
     pumpPendingSpeculations();
 }
+void HTMLDocumentParser::didReceiveEncodingDataFromBackgroundParser(const DocumentEncodingData& data)

[abarth-chromium, 2013/11/18 06:57:10]

Missing a blank line above this line.

[oystein (OOO til 10th of July), 2013/11/18 22:18:42]

Done.

+{
+    document()->setEncodingData(data);
+}
 
 void HTMLDocumentParser::validateSpeculations(PassOwnPtr<ParsedChunk> chunk)
 {
@@ -675,7 +680,8 @@ void HTMLDocumentParser::startBackgroundParser()
 
     ASSERT(config->xssAuditor->isSafeToSendToAnotherThread());
     ASSERT(config->preloadScanner->isSafeToSendToAnotherThread());
-    HTMLParserThread::shared()->postTask(bind(&BackgroundHTMLParser::create, reference.release(), config.release()));
+    OwnPtr<TextResourceDecoder> decoder = adoptDecoder();
+    HTMLParserThread::shared()->postTask(bind(&BackgroundHTMLParser::create, reference.release(), config.release(), decoder.release()));
 }
 
 void HTMLDocumentParser::stopBackgroundParser()
@@ -693,19 +699,9 @@ void HTMLDocumentParser::append(PassRefPtr<StringImpl> inputSource)
     if (isStopped())
         return;
 
-    if (shouldUseThreading()) {
-        if (!m_haveBackgroundParser)
-            startBackgroundParser();
-
-        ASSERT(inputSource->hasOneRef());
-        TRACE_EVENT1("net", "HTMLDocumentParser::append", "size", inputSource->length());

[eseidel, 2013/11/18 20:07:40]

We've lost this trace event now.  I'm not sure that matters.

[oystein (OOO til 10th of July), 2013/11/18 22:18:42]

Added to appendBytes() now, just in case.

-        // NOTE: Important that the String temporary is destroyed before we post the task
-        // otherwise the String could call deref() on a StringImpl now owned by the background parser.
-        // We would like to ASSERT(closure.arg3()->hasOneRef()) but sadly the args are private.
-        Closure closure = bind(&BackgroundHTMLParser::append, m_backgroundParser, String(inputSource));
-        HTMLParserThread::shared()->postTask(closure);
-        return;
-    }
+    // We should never reach this point if we're using a parser thread,
+    // as appendBytes() will directly ship the data to the thread.
+    ASSERT(!shouldUseThreading());
 
     // pumpTokenizer can cause this parser to be detached from the Document,
     // but we need to ensure it isn't deleted yet.
@@ -971,4 +967,32 @@ void HTMLDocumentParser::resumeScheduledTasks()
         m_parserScheduler->resume();
 }
 
+void HTMLDocumentParser::appendBytes(const char* data, size_t length)
+{
+    if (!length || isDetached())
+        return;
+
+    if (shouldUseThreading()) {
+        if (!m_haveBackgroundParser)
+            startBackgroundParser();
+
+        HTMLParserThread::shared()->postTask(bind(&BackgroundHTMLParser::appendBytes, m_backgroundParser, SharedBuffer::create(data, length)));

[abarth-chromium, 2013/11/18 06:57:10]

Why a SharedBuffer and not just a Vector?  It's too bad we're introducing this
extra copy.

[oystein (OOO til 10th of July), 2013/11/18 22:18:42]

I didn't see any other buffer classes when I looked; Vector definitely makes
sense. Done.

This copy just replaces the one done in HTMLDocumentParser::append() (if I'm
reading it right) , but would still be nice to avoid. Maybe the appendBytes()
could be switched to passing around a SharedBuffer argument instead, but I don't
know the full consequences of that.

+        return;
+    }
+
+    DecodedDataDocumentParser::appendBytes(data, length);
+}
+
+void HTMLDocumentParser::flush()
+{
+    // If we've got no decoder, we never received any data.
+    if (isDetached() || needsDecoder())
+        return;
+
+    if (m_haveBackgroundParser)
+        HTMLParserThread::shared()->postTask(bind(&BackgroundHTMLParser::flush, m_backgroundParser));
+    else
+        DecodedDataDocumentParser::flush();
+}
+
 }