Bug 1129871 - Favor passing tiles by ref rather than copy part 1. r=BenWa

gfx/layers/TiledLayerBuffer.h

@@ -544,8 +544,8 @@ TiledLayerBuffer<Derived, Tile>::Update(const nsIntRegion& newValidRegion,
       // in which case it's up to the derived class's ValidateTile()
       // implementation to allocate a new tile before drawing
       nsIntPoint tileOrigin(tileStartX, tileStartY);
-      newTile = AsDerived().ValidateTile(newTile, nsIntPoint(tileStartX, tileStartY),
-                                         tileDrawRegion);
+      AsDerived().ValidateTile(newTile, nsIntPoint(tileStartX, tileStartY),
+                               tileDrawRegion);
       NS_ASSERTION(!newTile.IsPlaceholderTile(), "Unexpected placeholder tile - failed to allocate?");
 #ifdef GFX_TILEDLAYER_PREF_WARNINGS
       printf_stderr("Store Validate tile %i, %i -> %i\n", tileStartX, tileStartY, index);

gfx/layers/client/TiledContentClient.cpp

@@ -1059,7 +1059,7 @@ ClientTiledLayerBuffer::PostValidate(const nsIntRegion& aPaintRegion)
 }
 
 void
-ClientTiledLayerBuffer::UnlockTile(TileClient aTile)
+ClientTiledLayerBuffer::UnlockTile(TileClient& aTile)
 {
   // We locked the back buffer, and flipped so we now need to unlock the front
   if (aTile.mFrontBuffer && aTile.mFrontBuffer->IsLocked()) {
@@ -1078,8 +1078,8 @@ ClientTiledLayerBuffer::UnlockTile(TileClient aTile)
   }
 }
 
-TileClient
-ClientTiledLayerBuffer::ValidateTile(TileClient aTile,
+void
+ClientTiledLayerBuffer::ValidateTile(TileClient& aTile,
                                     const nsIntPoint& aTileOrigin,
                                     const nsIntRegion& aDirtyRegion)
 {
@@ -1120,27 +1120,24 @@ ClientTiledLayerBuffer::ValidateTile(TileClient aTile,
 
   if (!backBuffer) {
     NS_WARNING("Failed to allocate a tile TextureClient");
-    aTile.DiscardBackBuffer();
-    aTile.DiscardFrontBuffer();
-    return TileClient();
+    aTile.Release();
+    return;
   }
 
   // the back buffer may have been already locked in ValidateBackBufferFromFront
   if (!backBuffer->IsLocked()) {
     if (!backBuffer->Lock(OpenMode::OPEN_READ_WRITE)) {
       NS_WARNING("Failed to lock a tile TextureClient");
-      aTile.DiscardBackBuffer();
-      aTile.DiscardFrontBuffer();
-      return TileClient();
+    aTile.Release();
+    return;
     }
   }
 
   if (backBufferOnWhite && !backBufferOnWhite->IsLocked()) {
     if (!backBufferOnWhite->Lock(OpenMode::OPEN_READ_WRITE)) {
       NS_WARNING("Failed to lock tile TextureClient for updating.");
-      aTile.DiscardBackBuffer();
-      aTile.DiscardFrontBuffer();
-      return TileClient();
+      aTile.Release();
+      return;
     }
   }
 
@@ -1148,15 +1145,13 @@ ClientTiledLayerBuffer::ValidateTile(TileClient aTile,
     if (createdTextureClient) {
       if (!mCompositableClient->AddTextureClient(backBuffer)) {
         NS_WARNING("Failed to add tile TextureClient.");
-        aTile.DiscardFrontBuffer();
-        aTile.DiscardBackBuffer();
-        return aTile;
+        aTile.Release();
+        return;
       }
       if (backBufferOnWhite && !mCompositableClient->AddTextureClient(backBufferOnWhite)) {
         NS_WARNING("Failed to add tile TextureClient.");
-        aTile.DiscardFrontBuffer();
-        aTile.DiscardBackBuffer();
-        return aTile;
+        aTile.Release();
+        return;
       }
     }
 
@@ -1172,9 +1167,9 @@ ClientTiledLayerBuffer::ValidateTile(TileClient aTile,
     }
     moz2DTile.mTileOrigin = gfx::IntPoint(aTileOrigin.x, aTileOrigin.y);
     if (!dt || (backBufferOnWhite && !dtOnWhite)) {
-      aTile.DiscardFrontBuffer();
-      aTile.DiscardBackBuffer();
-      return aTile;
+      NS_WARNING("Failed to get a DrawTarget from a tile");
+      aTile.Release();
+      return;
     }
 
     mMoz2DTiles.push_back(moz2DTile);
@@ -1207,7 +1202,7 @@ ClientTiledLayerBuffer::ValidateTile(TileClient aTile,
 
     aTile.Flip();
 
-    return aTile;
+    return;
   }
 
   // Single paint buffer case:
@@ -1291,9 +1286,8 @@ ClientTiledLayerBuffer::ValidateTile(TileClient aTile,
   if (createdTextureClient) {
     if (!mCompositableClient->AddTextureClient(backBuffer)) {
       NS_WARNING("Failed to add tile TextureClient.");
-      aTile.DiscardFrontBuffer();
-      aTile.DiscardBackBuffer();
-      return aTile;
+      aTile.Release();
+      return;
     }
   }
 
@@ -1307,8 +1301,6 @@ ClientTiledLayerBuffer::ValidateTile(TileClient aTile,
     // TextureClient around unnecessarily, so discard the back-buffer.
     aTile.DiscardBackBuffer();
   }
-
-  return aTile;
 }
 
 /**

gfx/layers/client/TiledContentClient.h

@@ -440,15 +440,15 @@ public:
   SurfaceDescriptorTiles GetSurfaceDescriptorTiles();
 
 protected:
-  TileClient ValidateTile(TileClient aTile,
-                          const nsIntPoint& aTileRect,
-                          const nsIntRegion& dirtyRect);
+  void ValidateTile(TileClient& aTile,
+                    const nsIntPoint& aTileRect,
+                    const nsIntRegion& dirtyRect);
 
   void PostValidate(const nsIntRegion& aPaintRegion);
 
-  void UnlockTile(TileClient aTile);
+  void UnlockTile(TileClient& aTile);
 
-  void ReleaseTile(TileClient aTile) { aTile.Release(); }
+  void ReleaseTile(TileClient& aTile) { aTile.Release(); }
 
   void SwapTiles(TileClient& aTileA, TileClient& aTileB) { std::swap(aTileA, aTileB); }
 

gfx/layers/composite/TiledContentHost.cpp

@@ -168,14 +168,14 @@ TiledLayerBufferComposite::Upload()
   ClearPaintedRegion();
 }
 
-TileHost
-TiledLayerBufferComposite::ValidateTile(TileHost aTile,
+void
+TiledLayerBufferComposite::ValidateTile(TileHost& aTile,
                                         const nsIntPoint& aTileOrigin,
                                         const nsIntRegion& aDirtyRect)
 {
   if (aTile.IsPlaceholderTile()) {
     NS_WARNING("Placeholder tile encountered in painted region");
-    return aTile;
+    return;
   }
 
 #ifdef GFX_TILEDLAYER_PREF_WARNINGS
@@ -205,7 +205,6 @@ TiledLayerBufferComposite::ValidateTile(TileHost aTile,
     printf_stderr("Tile Time to upload %i\n", PR_IntervalNow() - start);
   }
 #endif
-  return aTile;
 }
 
 void

gfx/layers/composite/TiledContentHost.h

@@ -164,9 +164,9 @@ public:
   static void RecycleCallback(TextureHost* textureHost, void* aClosure);
 
 protected:
-  TileHost ValidateTile(TileHost aTile,
-                        const nsIntPoint& aTileRect,
-                        const nsIntRegion& dirtyRect);
+  void ValidateTile(TileHost& aTile,
+                    const nsIntPoint& aTileRect,
+                    const nsIntRegion& dirtyRect);
 
   // do nothing, the desctructor in the texture host takes care of releasing resources
   void ReleaseTile(TileHost aTile) {}