SSE2 implementation of memcpy32

src/opts/SkUtils_opts_SSE2.cpp

Index: src/opts/SkUtils_opts_SSE2.cpp
diff --git a/src/opts/SkUtils_opts_SSE2.cpp b/src/opts/SkUtils_opts_SSE2.cpp
index a3c5aa5dfd7f1cf417abda23f10d662d80bf8045..bd2f9b29a44ad612a93b14ee57c16b16d54b1f8f 100644
--- a/src/opts/SkUtils_opts_SSE2.cpp
+++ b/src/opts/SkUtils_opts_SSE2.cpp
@@ -67,3 +67,33 @@ void sk_memset32_SSE2(uint32_t *dst, uint32_t value, int count)
         --count;
     }
 }
+
+void sk_memcpy32_SSE2(uint32_t *dst, const uint32_t *src, int count)
+{
+    if (count >= 16) {
+        while (((size_t)dst) & 0x0F) {
+            *dst++ = *src++;
+            --count;
+        }
+        __m128i *dst128 = reinterpret_cast<__m128i*>(dst);
+        const __m128i *src128 = reinterpret_cast<const __m128i*>(src);
+        while (count >= 16) {
+            __m128i a =  _mm_loadu_si128(src128++);
+            __m128i b =  _mm_loadu_si128(src128++);
+            __m128i c =  _mm_loadu_si128(src128++);
+            __m128i d =  _mm_loadu_si128(src128++);
+
+            _mm_store_si128(dst128++, a);
+            _mm_store_si128(dst128++, b);
+            _mm_store_si128(dst128++, c);
+            _mm_store_si128(dst128++, d);
+            count -= 16;
+        }
+        dst = reinterpret_cast<uint32_t*>(dst128);
+        src = reinterpret_cast<const uint32_t*>(src128);
+    }
+    while (count > 0) {
+        *dst++ = *src++;
+        --count;
+    }
+}