Changeset 135862 in webkit

Timestamp:

Nov 27, 2012 7:50:07 AM (11 years ago)

Author:

haraken@chromium.org

Message:

[V8] Remove V8StringResource::m_string
​https://bugs.webkit.org/show_bug.cgi?id=103367

Reviewed by Adam Barth.

This patch cleans up V8StringResource and removes V8StringResource::m_string.
This patch won't change performance. (This patch just adds one redundant IsString()
check and one IsInt32() check.) I confirmed no performance regression in micro benchmarks
(​https://bugs.webkit.org/attachment.cgi?id=176178).

No tests. No change in behavior.

• bindings/v8/V8Binding.cpp:

(WebCore::v8NonStringValueToWebCoreString):

• bindings/v8/V8StringResource.cpp:

(WebCore::int32ToWebCoreStringFast):
(WebCore::String):
(WebCore::AtomicString):
(WebCore):

• bindings/v8/V8StringResource.h:

(WebCore::V8StringResource::V8StringResource):
(WebCore::V8StringResource::prepareBase):
(WebCore::V8StringResource::toString):
(V8StringResource):
(WebCore::::prepare):

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• bindings/v8/V8Binding.cpp (modified) (1 diff)
• bindings/v8/V8StringResource.cpp (modified) (3 diffs)
• bindings/v8/V8StringResource.h (modified) (6 diffs)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2012-11-27  Kentaro Hara  <haraken@chromium.org>
+
+        [V8] Remove V8StringResource::m_string
+        https://bugs.webkit.org/show_bug.cgi?id=103367
+
+        Reviewed by Adam Barth.
+
+        This patch cleans up V8StringResource and removes V8StringResource::m_string.
+        This patch won't change performance. (This patch just adds one redundant IsString()
+        check and one IsInt32() check.) I confirmed no performance regression in micro benchmarks
+        (https://bugs.webkit.org/attachment.cgi?id=176178).
+
+        No tests. No change in behavior.
+
+        * bindings/v8/V8Binding.cpp:
+        (WebCore::v8NonStringValueToWebCoreString):
+        * bindings/v8/V8StringResource.cpp:
+        (WebCore::int32ToWebCoreStringFast):
+        (WebCore::String):
+        (WebCore::AtomicString):
+        (WebCore):
+        * bindings/v8/V8StringResource.h:
+        (WebCore::V8StringResource::V8StringResource):
+        (WebCore::V8StringResource::prepareBase):
+        (WebCore::V8StringResource::toString):
+        (V8StringResource):
+        (WebCore::::prepare):
+
 2012-11-27  Alec Flett  <alecflett@chromium.org>
 

trunk/Source/WebCore/bindings/v8/V8Binding.cpp

@@ -101 +101 @@
     ASSERT(!object->IsString());
     if (object->IsInt32())
-        return int32ToWebCoreString(object->Int32Value());
+        return int32ToWebCoreString<String>(object->Int32Value());
 
     v8::TryCatch block;

trunk/Source/WebCore/bindings/v8/V8StringResource.cpp

@@ -191 +191 @@
     // Most numbers used are <= 100. Even if they aren't used there's very little cost in using the space.
     const int kLowNumbers = 100;
+
+    // FIXME: Store lowNumbers in V8PerIsolateData so that workers can also use them.
     DEFINE_STATIC_LOCAL(Vector<AtomicString>, lowNumbers, (kLowNumbers + 1));
     String webCoreString;
@@ -205 +207 @@
 }
 
-String int32ToWebCoreString(int value)
+template<> String int32ToWebCoreString<String>(int value)
 {
     // If we are on the main thread (this should always true for non-workers), call the faster one.
@@ -213 +215 @@
 }
 
+template<> AtomicString int32ToWebCoreString<AtomicString>(int value)
+{
+    return AtomicString(int32ToWebCoreString<String>(value));
+}
+
 } // namespace WebCore

trunk/Source/WebCore/bindings/v8/V8StringResource.h

@@ -143 +143 @@
 template <typename StringType>
 StringType v8StringToWebCoreString(v8::Handle<v8::String>, ExternalMode);
-String int32ToWebCoreString(int value);
+template <typename StringType>
+StringType int32ToWebCoreString(int value);
 
 // V8StringResource is an adapter class that converts V8 values to Strings
@@ -159 +160 @@
         : m_v8Object(object)
         , m_mode(Externalize)
-        , m_string()
     {
     }
@@ -170 +170 @@
     bool prepareBase()
     {
-        if (m_v8Object.IsEmpty())
+        ASSERT(!m_v8Object.IsEmpty());
+        if (LIKELY(m_v8Object->IsString() || m_v8Object->IsInt32()))
             return true;
-
-        if (LIKELY(m_v8Object->IsString()))
-            return true;
-
-        if (LIKELY(m_v8Object->IsInt32())) {
-            setString(int32ToWebCoreString(m_v8Object->Int32Value()));
-            return true;
-        }
 
         m_mode = DoNotExternalize;
@@ -192 +185 @@
     }
 
-    void setString(const String& string)
-    {
-        m_string = string;
-        m_v8Object.Clear(); // To signal that String is ready.
-    }
-
     template <class StringType>
     StringType toString()
     {
-        if (LIKELY(!m_v8Object.IsEmpty()))
-            return v8StringToWebCoreString<StringType>(m_v8Object.As<v8::String>(), m_mode);
-
-        return StringType(m_string);
+        if (m_v8Object.IsEmpty())
+            return StringType();
+        if (m_v8Object->IsInt32())
+            return int32ToWebCoreString<StringType>(m_v8Object->Int32Value());
+        ASSERT(m_v8Object->IsString());
+        return v8StringToWebCoreString<StringType>(m_v8Object.As<v8::String>(), m_mode);
     }
 
     v8::Local<v8::Value> m_v8Object;
     ExternalMode m_mode;
-    String m_string;
 };
 
 template<> inline bool V8StringResource<DefaultMode>::prepare()
 {
+    if (m_v8Object.IsEmpty())
+        return true;
     return prepareBase();
 }
@@ -220 +210 @@
 {
     if (m_v8Object.IsEmpty() || m_v8Object->IsNull()) {
-        setString(String());
+        m_v8Object.Clear();
         return true;
     }
@@ -229 +219 @@
 {
     if (m_v8Object.IsEmpty() || m_v8Object->IsNull() || m_v8Object->IsUndefined()) {
-        setString(String());
+        m_v8Object.Clear();
         return true;
     }