Optimize CMYK->RGBA (BGRA) transform for jpeg decodes

src/codec/SkSwizzler.cpp

Index: src/codec/SkSwizzler.cpp
diff --git a/src/codec/SkSwizzler.cpp b/src/codec/SkSwizzler.cpp
index debcd45c207048b5e96279a7ed5001e0695628cb..f9f212072e53e4bb2565e87aadb6fdff0213c1e6 100644
--- a/src/codec/SkSwizzler.cpp
+++ b/src/codec/SkSwizzler.cpp
@@ -592,6 +592,21 @@ static void swizzle_cmyk_to_n32(
     }
 }
 
+static void fast_swizzle_cmyk_to_n32(
+        void* dst, const uint8_t* src, int width, int bpp, int deltaSrc, int offset,
+        const SkPMColor ctable[]) {
+
+    // This function must not be called if we are sampling.  If we are not
+    // sampling, deltaSrc should equal bpp.
+    SkASSERT(deltaSrc == bpp);
+
+#ifdef SK_PMCOLOR_IS_RGBA
+    SkOpts::inverted_CMYK_to_RGB1((uint32_t*) dst, src + offset, width);
+#else
+    SkOpts::inverted_CMYK_to_BGR1((uint32_t*) dst, src + offset, width);
+#endif
+}
+
 static void swizzle_cmyk_to_565(
         void* SK_RESTRICT dstRow, const uint8_t* SK_RESTRICT src, int dstWidth,
         int bpp, int deltaSrc, int offset, const SkPMColor ctable[]) {
@@ -811,6 +826,7 @@ SkSwizzler* SkSwizzler::CreateSwizzler(SkSwizzler::SrcConfig sc,
                     break;
                 case kRGB_565_SkColorType:
                     proc = &swizzle_rgb_to_565;
+                    break;
                 default:
                     break;
             }
@@ -844,6 +860,7 @@ SkSwizzler* SkSwizzler::CreateSwizzler(SkSwizzler::SrcConfig sc,
             switch (dstInfo.colorType()) {
                 case kN32_SkColorType:
                     proc = &swizzle_cmyk_to_n32;
+                    fastProc = &fast_swizzle_cmyk_to_n32;
                     break;
                 case kRGB_565_SkColorType:
                     proc = &swizzle_cmyk_to_565;