Xfermode: SSE2 implementation of multiply_modeproc

src/opts/SkColor_opts_SSE2.h

Index: src/opts/SkColor_opts_SSE2.h
diff --git a/src/opts/SkColor_opts_SSE2.h b/src/opts/SkColor_opts_SSE2.h
index 13a5be5655631d1c1dcd365f72435c1df97b8c68..24ab6f73c8da13653fecf560f7ca8b4fdd08103f 100644
--- a/src/opts/SkColor_opts_SSE2.h
+++ b/src/opts/SkColor_opts_SSE2.h
@@ -10,7 +10,39 @@
 
 #include <emmintrin.h>
 
-static inline __m128i SkMul16ShiftRound_SSE(__m128i a, __m128i b, int shift) {
+// See #define SkAlphaMulAlpha(a, b)  SkMulDiv255Round(a, b) in SkXfermode.cpp.
+static inline __m128i SkAlphaMulAlpha_SSE2(const __m128i& a,
+                                           const __m128i& b) {
+    __m128i prod = _mm_mullo_epi16(a, b);
+    prod = _mm_add_epi32(prod, _mm_set1_epi32(128));
+    prod = _mm_add_epi32(prod, _mm_srli_epi32(prod, 8));
+    prod = _mm_srli_epi32(prod, 8);
+
+    return prod;
+}
+
+static inline __m128i SkGetPackedA32_SSE2(const __m128i& src) {
+    __m128i a = _mm_slli_epi32(src, (24 - SK_A32_SHIFT));
+    return _mm_srli_epi32(a, 24);
+}
+
+static inline __m128i SkGetPackedR32_SSE2(const __m128i& src) {
+    __m128i r = _mm_slli_epi32(src, (24 - SK_R32_SHIFT));
+    return _mm_srli_epi32(r, 24);
+}
+
+static inline __m128i SkGetPackedG32_SSE2(const __m128i& src) {
+    __m128i g = _mm_slli_epi32(src, (24 - SK_G32_SHIFT));
+    return _mm_srli_epi32(g, 24);
+}
+
+static inline __m128i SkGetPackedB32_SSE2(const __m128i& src) {
+    __m128i b = _mm_slli_epi32(src, (24 - SK_B32_SHIFT));
+    return _mm_srli_epi32(b, 24);
+}
+
+static inline __m128i SkMul16ShiftRound_SSE2(const __m128i& a,
+                                             const __m128i& b, int shift) {
     __m128i prod = _mm_mullo_epi16(a, b);
     prod = _mm_add_epi16(prod, _mm_set1_epi16(1 << (shift - 1)));
     prod = _mm_add_epi16(prod, _mm_srli_epi16(prod, shift));
@@ -19,13 +51,96 @@ static inline __m128i SkMul16ShiftRound_SSE(__m128i a, __m128i b, int shift) {
     return prod;
 }
 
-static inline __m128i SkPackRGB16_SSE(__m128i r, __m128i g, __m128i b) {
-    r = _mm_slli_epi16(r, SK_R16_SHIFT);
-    g = _mm_slli_epi16(g, SK_G16_SHIFT);
-    b = _mm_slli_epi16(b, SK_B16_SHIFT);
+static inline __m128i SkPackRGB16_SSE2(const __m128i& r,
+                                       const __m128i& g, const __m128i& b) {
+    __m128i dr = _mm_slli_epi16(r, SK_R16_SHIFT);
+    __m128i dg = _mm_slli_epi16(g, SK_G16_SHIFT);
+    __m128i db = _mm_slli_epi16(b, SK_B16_SHIFT);
+
+    __m128i c = _mm_or_si128(dr, dg);
+    return _mm_or_si128(c, db);
+}
+
+static inline __m128i SkPackARGB32_SSE2(const __m128i& a, const __m128i& r,
+                                        const __m128i& g, const __m128i& b) {
+    __m128i da = _mm_slli_epi32(a, SK_A32_SHIFT);
+    __m128i dr = _mm_slli_epi32(r, SK_R32_SHIFT);
+    __m128i dg = _mm_slli_epi32(g, SK_G32_SHIFT);
+    __m128i db = _mm_slli_epi32(b, SK_B32_SHIFT);
+
+    __m128i c = _mm_or_si128(da, dr);
+    c = _mm_or_si128(c, dg);
+    return _mm_or_si128(c, db);
+}
+
+static inline __m128i SkPacked16ToR32_SSE2(const __m128i& src) {
+    __m128i r = _mm_srli_epi32(src, SK_R16_SHIFT);
+    r = _mm_and_si128(r, _mm_set1_epi32(SK_R16_MASK));
+    r = _mm_or_si128(_mm_slli_epi32(r, (8 - SK_R16_BITS)),
+                     _mm_srli_epi32(r, (2 * SK_R16_BITS - 8)));
+
+    return r;
+}
+
+static inline __m128i SkPacked16ToG32_SSE2(const __m128i& src) {
+    __m128i g = _mm_srli_epi32(src, SK_G16_SHIFT);
+    g = _mm_and_si128(g, _mm_set1_epi32(SK_G16_MASK));
+    g = _mm_or_si128(_mm_slli_epi32(g, (8 - SK_G16_BITS)),
+                     _mm_srli_epi32(g, (2 * SK_G16_BITS - 8)));
+
+    return g;
+}
+
+static inline __m128i SkPacked16ToB32_SSE2(const __m128i& src) {
+    __m128i b = _mm_srli_epi32(src, SK_B16_SHIFT);
+    b = _mm_and_si128(b, _mm_set1_epi32(SK_B16_MASK));
+    b = _mm_or_si128(_mm_slli_epi32(b, (8 - SK_B16_BITS)),
+                     _mm_srli_epi32(b, (2 * SK_B16_BITS - 8)));
+
+    return b;
+}
+
+static inline __m128i SkPixel16ToPixel32_SSE2(const __m128i& src) {
+    __m128i r = SkPacked16ToR32_SSE2(src);
+    __m128i g = SkPacked16ToG32_SSE2(src);
+    __m128i b = SkPacked16ToB32_SSE2(src);
+
+    return SkPackARGB32_SSE2(_mm_set1_epi32(0xFF), r, g, b);
+}
+
+static inline __m128i SkPixel32ToPixel16_ToU16_SSE2(const __m128i& src_pixel1,
+                                                    const __m128i& src_pixel2) {
+    // Calculate result r.
+    __m128i r1 = _mm_srli_epi32(src_pixel1,
+                                SK_R32_SHIFT + (8 - SK_R16_BITS));
+    r1 = _mm_and_si128(r1, _mm_set1_epi32(SK_R16_MASK));
+    __m128i r2 = _mm_srli_epi32(src_pixel2,
+                                SK_R32_SHIFT + (8 - SK_R16_BITS));
+    r2 = _mm_and_si128(r2, _mm_set1_epi32(SK_R16_MASK));
+    __m128i r = _mm_packs_epi32(r1, r2);
+
+    // Calculate result g.
+    __m128i g1 = _mm_srli_epi32(src_pixel1,
+                                SK_G32_SHIFT + (8 - SK_G16_BITS));
+    g1 = _mm_and_si128(g1, _mm_set1_epi32(SK_G16_MASK));
+    __m128i g2 = _mm_srli_epi32(src_pixel2,
+                                SK_G32_SHIFT + (8 - SK_G16_BITS));
+    g2 = _mm_and_si128(g2, _mm_set1_epi32(SK_G16_MASK));
+    __m128i g = _mm_packs_epi32(g1, g2);
+
+    // Calculate result b.
+    __m128i b1 = _mm_srli_epi32(src_pixel1,
+                                SK_B32_SHIFT + (8 - SK_B16_BITS));
+    b1 = _mm_and_si128(b1, _mm_set1_epi32(SK_B16_MASK));
+    __m128i b2 = _mm_srli_epi32(src_pixel2,
+                                SK_B32_SHIFT + (8 - SK_B16_BITS));
+    b2 = _mm_and_si128(b2, _mm_set1_epi32(SK_B16_MASK));
+    __m128i b = _mm_packs_epi32(b1, b2);
+
+    // Store 8 16-bit colors in dst.
+    __m128i d_pixel = SkPackRGB16_SSE2(r, g, b);
 
-    __m128i c = _mm_or_si128(r, g);
-    return _mm_or_si128(c, b);
+    return d_pixel;
 }
 
-#endif//SkColor_opts_SSE2_DEFINED
+#endif // SkColor_opts_SSE2_DEFINED