Replace SSE optimization of Color32A_D565

src/core/SkBlitRow_D16.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBlitRow.h"
 #include "SkColorPriv.h"
 #include "SkDither.h"
@@ skipping 198 matching lines @@
     unsigned g = SkGetPackedG32(c);
     unsigned b = SkGetPackedB32(c);
     return (g << 24) | (r << 13) | (b << 2);
 }
 
 static void Color32A_D565(uint16_t dst[], SkPMColor src, int count, int x, int y) {
     SkASSERT(count > 0);
     uint32_t src_expand = pmcolor_to_expand16(src);
     unsigned scale = SkAlpha255To256(0xFF - SkGetPackedA32(src)) >> 3;
     do {
-        uint32_t dst_expand = SkExpand_rgb_16(*dst) * scale;
-        *dst = SkCompact_rgb_16((src_expand + dst_expand) >> 5);
+        *dst = SkBlend32_RGB16(src_expand, *dst, scale);
         dst += 1;
     } while (--count != 0);
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 ///////////////////////////////////////////////////////////////////////////////
 
 static const SkBlitRow::Proc16 gDefault_565_Procs[] = {
     // no dither
     S32_D565_Opaque,
@@ skipping 31 matching lines @@
     Color32A_D565,
     Color32A_D565,
 #endif
 };
 
 SkBlitRow::ColorProc16 SkBlitRow::ColorFactory16(unsigned flags) {
     SkASSERT((flags & ~kFlags16_Mask) == 0);
     // just so we don't crash
     flags &= kFlags16_Mask;
     // we ignore both kGlobalAlpha_Flag and kSrcPixelAlpha_Flag, so shift down
-    // since this factory is only used for transparent source alphas
+    // no need for the additional code specializing on opaque alpha at this time
     flags >>= 2;
 
     SkASSERT(flags < SK_ARRAY_COUNT(gDefault_565_ColorProcs));
 
     SkBlitRow::ColorProc16 proc = PlatformColorFactory565(flags);
     if (NULL == proc) {
         proc = gDefault_565_ColorProcs[flags];
     }
     return proc;
 }