Use SharedBuffer!=() in CachedResource::tryReplaceEncodedData()

cdumez · cdumez · commit c141f2bb77e2 · 2021-06-11T23:36:33.000Z
https://bugs.webkit.org/show_bug.cgi?id=226943 Reviewed by Geoff Garen. Use SharedBuffer!=() in CachedResource::tryReplaceEncodedData() instead of duplicating its logic. SharedBuffer!=() is also potentially more efficient since it doesn't requires combining the SharedBuffers' data segments. * loader/cache/CachedResource.cpp: (WebCore::CachedResource::tryReplaceEncodedData): Canonical link: https://commits.webkit.org/238750@main git-svn-id: https://svn.webkit.org/repository/webkit/trunk@278793 268f45cc-cd09-0410-ab3c-d52691b4dbfc
diff --git a/Source/WebCore/ChangeLog b/Source/WebCore/ChangeLog
@@ -1,3 +1,17 @@
+2021-06-11  Chris Dumez  <cdumez@apple.com>
+
+        Use SharedBuffer!=() in CachedResource::tryReplaceEncodedData()
+        https://bugs.webkit.org/show_bug.cgi?id=226943
+
+        Reviewed by Geoff Garen.
+
+        Use SharedBuffer!=() in CachedResource::tryReplaceEncodedData() instead of duplicating its logic.
+        SharedBuffer!=() is also potentially more efficient since it doesn't requires combining the
+        SharedBuffers' data segments.
+
+        * loader/cache/CachedResource.cpp:
+        (WebCore::CachedResource::tryReplaceEncodedData):
+
 2021-06-11  Imanol Fernandez  <ifernandez@igalia.com>
 
         Implement Encode/Decode templates for WebXR InputSources
diff --git a/Source/WebCore/loader/cache/CachedResource.cpp b/Source/WebCore/loader/cache/CachedResource.cpp
@@ -914,10 +914,10 @@ void CachedResource::tryReplaceEncodedData(SharedBuffer& newBuffer)
     if (!mayTryReplaceEncodedData())
         return;
 
-    // We have to do the memcmp because we can't tell if the replacement file backed data is for the
-    // same resource or if we made a second request with the same URL which gave us a different
-    // resource. We have seen this happen for cached POST resources.
-    if (m_data->size() != newBuffer.size() || memcmp(m_data->data(), newBuffer.data(), m_data->size()))
+    // We have to compare the buffers because we can't tell if the replacement file backed data is for the
+    // same resource or if we made a second request with the same URL which gave us a different resource.
+    // We have seen this happen for cached POST resources.
+    if (*m_data != newBuffer)
         return;
 
     m_data->clear();
