Rewriting MatrixConvolution image filter with SSE and AVX2

src/core/SkOpts.cpp

Index: src/core/SkOpts.cpp
diff --git a/src/core/SkOpts.cpp b/src/core/SkOpts.cpp
index 50659d4590fa95948b02cd1fea2e16afbe274528..102247ed08edfcc3d97f2459dca474519eea91f4 100644
--- a/src/core/SkOpts.cpp
+++ b/src/core/SkOpts.cpp
@@ -19,6 +19,7 @@
 #include "SkSwizzler_opts.h"
 #include "SkTextureCompressor_opts.h"
 #include "SkXfermode_opts.h"
+#include "SkMatrixConvolutionImageFilter_opts.h"
 
 namespace SK_OPTS_NS {
     static void float_to_half(uint16_t dst[], const float src[], int n) {
@@ -106,19 +107,29 @@ namespace SkOpts {
     decltype(half_to_float) half_to_float = sk_default::half_to_float;
     decltype(float_to_half) float_to_half = sk_default::float_to_half;
 
+    decltype(matrix_convolution_image_filter_filter_pixels) matrix_convolution_image_filter_filter_pixels = sk_default::SkMatrixConvolutionImageFilter_filterPixels_none;
+
     // Each Init_foo() is defined in src/opts/SkOpts_foo.cpp.
+    void Init_sse_sse2();
     void Init_ssse3();
     void Init_sse41();
     void Init_sse42() {}
     void Init_avx() {}
-    void Init_avx2() {}
+    void Init_avx2();
     void Init_neon();
 
     static void init() {
         // TODO: Chrome's not linking _sse* opts on iOS simulator builds.  Bug or feature?
     #if defined(SK_CPU_X86) && !defined(SK_BUILD_FOR_IOS)
+
+        // 'opts' target for x86 is already compiled with -msse2. Therefore, MMX, SSE, SSE2
+        // should be supported by every x86 CPU. So, just call Init_sse_sse2 function without
+        // any additional check.
+        Init_sse_sse2();
+
         uint32_t abcd[] = {0,0,0,0};
         cpuid(abcd);
+
         if (abcd[2] & (1<< 9)) { Init_ssse3(); }
         if (abcd[2] & (1<<19)) { Init_sse41(); }
         if (abcd[2] & (1<<20)) { Init_sse42(); }