SIMD implementation of Convolver for Lanczos filter etc.

skia/ext/convolver.h

Index: skia/ext/convolver.h
diff --git a/skia/ext/convolver.h b/skia/ext/convolver.h
index 04d6fe5c52db2e05218b8973c5e90b944e0b5d8f..e56efa0db85eb975b285fecee7c291ee6b2f6b9c 100644
--- a/skia/ext/convolver.h
+++ b/skia/ext/convolver.h
@@ -98,6 +98,13 @@ class ConvolutionFilter1D {
     return &filter_values_[filter.data_location];
   }
 
+  inline void PaddingForSIMD(int align) {
+    // Padding more coefficients to allow SIMD to load after the last one.
+    // This has to be done after all |AddFilter| calls.
+    for (int i = 0; i < align; ++i)
+      filter_values_.push_back(static_cast<Fixed>(0));
+  }
+
  private:
   struct FilterInstance {
     // Offset within filter_values for this instance of the filter.
@@ -146,7 +153,8 @@ void BGRAConvolve2D(const unsigned char* source_data,
                     const ConvolutionFilter1D& xfilter,
                     const ConvolutionFilter1D& yfilter,
                     int output_byte_row_stride,
-                    unsigned char* output);
+                    unsigned char* output,
+                    bool use_sse2 = false);
 
 }  // namespace skia