Change code to not store Sk4* in data structures.

src/core/SkLinearBitmapPipeline.h

Index: src/core/SkLinearBitmapPipeline.h
diff --git a/src/core/SkLinearBitmapPipeline.h b/src/core/SkLinearBitmapPipeline.h
index 3abdb8014aa134503d7694c7c9ba25705572d42e..d8b78ea833777269c50f42532abf33c231be375c 100644
--- a/src/core/SkLinearBitmapPipeline.h
+++ b/src/core/SkLinearBitmapPipeline.h
@@ -84,7 +84,7 @@ public:
 
     private:
         std::function<void (Next*, void*)> fStageCloner;
-        alignas(16) mutable char           fSpace[kSize];
+        mutable char                       fSpace[kSize];
         bool                               fIsInitialized;
     };
 
@@ -113,8 +113,8 @@ public:
         Base& operator*() const { return *(this->get()); }
 
     private:
-        alignas(16) mutable char fSpace[kSize];
-        bool                     fIsInitialized;
+        mutable char fSpace[kSize];
+        bool         fIsInitialized;
 
     };
 
@@ -125,8 +125,8 @@ public:
     class PixelAccessorInterface;
 
     // These values were generated by the assert above in Stage::init{Sink|Stage}.
-    using MatrixStage  = Stage<PointProcessorInterface,    160, PointProcessorInterface>;
-    using TileStage    = Stage<PointProcessorInterface,    160, SampleProcessorInterface>;
+    using MatrixStage  = Stage<PointProcessorInterface,     56, PointProcessorInterface>;
+    using TileStage    = Stage<PointProcessorInterface,     48, SampleProcessorInterface>;
     using SampleStage  = Stage<SampleProcessorInterface,   160, BlendProcessorInterface>;
     using BlenderStage = Stage<BlendProcessorInterface,     48>;
     using Accessor     = PolyMemory<PixelAccessorInterface, 64>;
@@ -147,29 +147,26 @@ class SkEmbeddableLinearPipeline {
 public:
     SkEmbeddableLinearPipeline() { }
     ~SkEmbeddableLinearPipeline() {
-        if (get() != nullptr) {
+        if (inited) {
             get()->~SkLinearBitmapPipeline();
         }
     }
 
     template <typename... Args>
     void init(Args&&... args) {
-        // Ensure that our pipeline is created at a 16 byte aligned address.
-        fPipeline = (SkLinearBitmapPipeline*)SkAlign16((intptr_t)fPipelineStorage);
-        new (fPipeline) SkLinearBitmapPipeline{std::forward<Args>(args)...};
+        new (fPipelineStorage) SkLinearBitmapPipeline{std::forward<Args>(args)...};
+        inited = true;
     }
 
-    SkLinearBitmapPipeline* get()        const { return fPipeline;    }
+    SkLinearBitmapPipeline* get() const {
+        return reinterpret_cast<SkLinearBitmapPipeline*>(fPipelineStorage);
+    }
     SkLinearBitmapPipeline& operator*()  const { return *this->get(); }
     SkLinearBitmapPipeline* operator->() const { return  this->get(); }
 
 private:
-    enum {
-        kActualSize = sizeof(SkLinearBitmapPipeline),
-        kPaddedSize = SkAlignPtr(kActualSize + 12),
-    };
-    void* fPipelineStorage[kPaddedSize / sizeof(void*)];
-    SkLinearBitmapPipeline* fPipeline{nullptr};
+    alignas(SkLinearBitmapPipeline) mutable char fPipelineStorage[sizeof(SkLinearBitmapPipeline)];

[mtklein_C, 2016/11/07 21:48:15]

Does this really need to be mutable?  Isn't it only changed in init()?

[herb_g, 2016/11/08 14:59:34]

It really does. The const on get() makes it so. In unique_ptr get() is const,
but through a pointer to the data. Here the data is in the object and needs to
be mutable to behave like a pointer to memory. 

+    bool inited {false};

[mtklein_C, 2016/11/07 21:48:15]

fInited, or fIsInitialized to be consistent with what you wrote above?

[herb_g, 2016/11/08 14:59:33]

Done.

 };
 
 #endif  // SkLinearBitmapPipeline_DEFINED