Bug 820132 - Measure imgFrame::mOptSurface's size where possible, instead of calculating it. r=joedrew.

--HG--
extra : rebase_source : da7616356429242e924a09df1124b1dbab13ad60

gfx/thebes/gfxASurface.h

@@ -199,6 +199,14 @@ public:
 
     virtual size_t SizeOfExcludingThis(nsMallocSizeOfFun aMallocSizeOf) const;
     virtual size_t SizeOfIncludingThis(nsMallocSizeOfFun aMallocSizeOf) const;
+    // gfxASurface has many sub-classes.  This method indicates if a sub-class
+    // is capable of measuring its own size accurately.  If not, the caller
+    // must fall back to a computed size.  (Note that gfxASurface can actually
+    // measure itself, but we must |return false| here because it serves as the
+    // (conservative) default for all the sub-classes.  Therefore, this
+    // function should only be called on a |gfxASurface*| that actually points
+    // to a sub-class of gfxASurface.)
+    virtual bool SizeOfIsMeasured() const { return false; }
 
     /**
      * The memory used by this surface (as reported by KnownMemoryUsed()) can

gfx/thebes/gfxImageSurface.cpp

@@ -190,6 +190,12 @@ gfxImageSurface::SizeOfIncludingThis(nsMallocSizeOfFun aMallocSizeOf) const
     return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
 }
 
+bool
+gfxImageSurface::SizeOfIsMeasured() const
+{
+    return true;
+}
+
 // helper function for the CopyFrom methods
 static void
 CopyForStride(unsigned char* aDest, unsigned char* aSrc, const gfxIntSize& aSize, long aDestStride, long aSrcStride)

gfx/thebes/gfxImageSurface.h

@@ -98,6 +98,7 @@ public:
         MOZ_OVERRIDE;
     virtual size_t SizeOfIncludingThis(nsMallocSizeOfFun aMallocSizeOf) const
         MOZ_OVERRIDE;
+    virtual bool SizeOfIsMeasured() const MOZ_OVERRIDE;
 
 protected:
     gfxImageSurface();

image/src/imgFrame.cpp

@@ -1,6 +1,6 @@
-/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
- *
- * This Source Code Form is subject to the terms of the Mozilla Public
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
@@ -813,7 +813,6 @@ imgFrame::SizeOfExcludingThisWithComputedFallbackIfHeap(gfxASurface::MemoryLocat
     n += n2;
   }
 
-  // XXX: should pass aMallocSizeOf here.  See bug 723827.
 #ifdef USE_WIN_SURFACE
   if (mWinSurface && aLocation == mWinSurface->GetMemoryLocation()) {
     n += mWinSurface->KnownMemoryUsed();
@@ -836,7 +835,16 @@ imgFrame::SizeOfExcludingThisWithComputedFallbackIfHeap(gfxASurface::MemoryLocat
   }
 
   if (mOptSurface && aLocation == mOptSurface->GetMemoryLocation()) {
-    n += mOptSurface->KnownMemoryUsed();
+    size_t n2 = 0;
+    if (aLocation == gfxASurface::MEMORY_IN_PROCESS_HEAP &&
+        mOptSurface->SizeOfIsMeasured()) {
+      // HEAP: measure (but only if the sub-class is capable of measuring)
+      n2 = mOptSurface->SizeOfIncludingThis(aMallocSizeOf);
+    }
+    if (n2 == 0) {  // non-HEAP or computed fallback for HEAP
+      n2 = mOptSurface->KnownMemoryUsed();
+    }
+    n += n2;
   }
 
   return n;