Add SkBlendARGB32_SSE2() to clean up code

Related nanobench results:
before:
maxrss  loops   min     median  mean    max     stddev  samples         config  bench
  10M   2       31.9µs  32.4µs  33.3µs  38.7µs  6%      █▄▂▂▂▁▂▁▁▁      8888    bitmap_BGRA_8888_A_scale_bicubic
  10M   13      43.8µs  51.8µs  49.6µs  57.9µs  11%     ▁▁▁▁▂▆▇▆▅█      8888    bitmap_BGRA_8888_A_scale_bilerp
  10M   13      23.7µs  24.3µs  26µs    32.7µs  13%     ▅█▆▁▁▁▁▂▁▁      8888    bitmap_Index_8_A
  10M   4       1.68µs  1.7µs   4.09µs  25.4µs  183%    █▁▁▁▁▁▁▁▁▁      8888    text_16_AA_88
  10M   144     1.76µs  1.77µs  1.78µs  1.81µs  1%      █▂▇▂▅▁▁▁▁▁      8888    text_16_AA_FF
  10M   10      4.7µs   5.34µs  5.61µs  8.63µs  21%     █▂▂▃▂▁▁▁▁▄      8888    rotated_rects_aa_alternating_transparent_and_opaque_src
  10M   50      4.44µs  4.47µs  4.5µs   4.71µs  2%      █▅▃▂▂▂▁▁▁▁      8888    rotated_rects_aa_changing_opaque_src
  10M   51      4.39µs  4.78µs  5.21µs  6.62µs  17%     ▁▆▆▇▁▁█▁▂▂      8888    rotated_rects_aa_same_opaque_src
  10M   50      4.47µs  5.79µs  5.43µs  6.14µs  11%     ▄▂▁▃▇▇▆▇▇█      8888    rotated_rects_aa_alternating_transparent_and_opaque_srcover
  10M   30      4.35µs  6.06µs  5.84µs  7.63µs  16%     ▅▅▅▄▅▅▄█▁▁      8888    rotated_rects_aa_changing_transparent_srcover
  10M   44      4.31µs  4.51µs  4.76µs  6.25µs  13%     ▄▂▂▁█▃▁▃▁▁      8888    rotated_rects_aa_changing_opaque_srcover
  10M   46      4.36µs  4.42µs  4.75µs  6.19µs  14%     ▆█▃▁▁▁▁▁▁▁      8888    rotated_rects_aa_same_transparent_srcover
  10M   47      4.29µs  4.35µs  4.44µs  5.15µs  6%      ▃▂▂▁▁█▁▁▁▁      8888    rotated_rects_aa_same_opaque_srcover
  10M   3       39.1µs  39.2µs  50.7µs  153µs   71%     █▁▁▁▁▁▁▁▁▁      8888    rectori
  10M   1       2.3ms   2.31ms  2.35ms  2.74ms  6%      ▁▁▁▁▁▁▁▁█▂      8888    maskcolor
  10M   1       2.33ms  2.34ms  2.53ms  3.14ms  11%     ▁▁▁▁▁▁▅█▄▄      8888    maskopaque
  10M   11      15µs    15.3µs  15.7µs  18.3µs  7%      ▅▃▂▂▁▁▁▁█▁      8888    rrects_3_stroke_4
  10M   46      3.99µs  4.07µs  4.14µs  4.54µs  4%      █▅▅▃▂▂▁▁▁▁      8888    rrects_3
  10M   16      15.6µs  15.9µs  16.1µs  17.5µs  4%      █▄▃▂▂▂▁▂▁▁      8888    ovals_3_stroke_4
  10M   40      5.09µs  5.18µs  5.23µs  5.67µs  3%      █▅▃▂▂▁▃▁▁▁      8888    ovals_3
  10M   231     1.92µs  1.93µs  1.94µs  2µs     1%      █▃▂▁▃▁▁▁▁▁      8888    zeroradroundrect
  10M   924     3.88µs  3.93µs  4.11µs  4.95µs  9%      ▁█▆▃▁▁▁▁▁▁      8888    arbroundrect
  10M   8       8.11µs  8.47µs  8.48µs  8.85µs  3%      █▅▇▄▄▂▁▄▄▆      8888    merge_large
  10M   14      6.71µs  6.92µs  6.96µs  7.46µs  3%      ▃▆▁█▃▃▃▂▂▁      8888    merge_small
  11M   2       225µs   227µs   229µs   233µs   1%      ███▃▇▂▃▁▃▂      8888    displacement_full_large
  16M   1       381µs   401µs   401µs   421µs   3%      ▅▅▅█▆▄▄▃▃▁      8888    displacement_alpha_large
  19M   1       507µs   508µs   509µs   512µs   0%      █▃▂▆▂▂▃▂▃▁      8888    displacement_zero_large
  19M   19      9µs     9.11µs  9.15µs  9.67µs  2%      ▄▂▂▂█▂▁▁▁▂      8888    displacement_full_small
  19M   5       54.2µs  54.5µs  54.9µs  58µs    2%      █▃▂▂▁▁▃▁▁▁      8888    blurroundrect_WH[100x100]_cr[90]
  20M   1       229µs   230µs   231µs   240µs   2%      █▄▃▂▂▁▁▁▁▂      8888    GM_varied_text_clipped_no_lcd
  20M   1       267µs   269µs   270µs   279µs   1%      █▄▃▂▂▂▂▂▁▁      8888    GM_varied_text_ignorable_clip_no_lcd
  22M   1       1.95ms  1.97ms  2.03ms  2.46ms  8%      ▁▁▁▁▁▁▁▂█▃      8888    GM_convex_poly_clip

after:
maxrss	loops	min	median	mean	max	stddev	samples   	config	bench
  10M	2	31.5µs	32.3µs	32.8µs	37.2µs	5%	█▄▃▂▂▂▁▁▁▁	8888	bitmap_BGRA_8888_A_scale_bicubic
  10M	13	43.9µs	44µs	44.1µs	44.9µs	1%	█▂▁▁▁▆▁▁▁▂	8888	bitmap_BGRA_8888_A_scale_bilerp
  10M	19	22.7µs	23.3µs	25.6µs	32.4µs	14%	▁▁▁▁▁▅▆▁▅█	8888	bitmap_Index_8_A
  10M	5	1.79µs	1.97µs	3.85µs	21.1µs	158%	█▁▁▁▁▁▁▁▁▁	8888	text_16_AA_88
  10M	141	1.83µs	1.83µs	1.85µs	1.93µs	2%	▅▁▁█▁▁▁▁▁▁	8888	text_16_AA_FF
  10M	10	4.65µs	4.92µs	5.06µs	6.56µs	11%	█▃▃▂▂▂▁▁▁▁	8888	rotated_rects_aa_alternating_transparent_and_opaque_src
  10M	51	4.35µs	4.48µs	4.83µs	6.68µs	17%	▂▁▁▁▁▁▁▂▆█	8888	rotated_rects_aa_changing_opaque_src
  10M	51	4.38µs	4.79µs	4.85µs	5.84µs	11%	▁█▁▃▃▁▄▁▄▇	8888	rotated_rects_aa_same_opaque_src
  10M	32	5.58µs	6.24µs	6.1µs	6.39µs	5%	█▂█▆▁▇▄▅▇▇	8888	rotated_rects_aa_alternating_transparent_and_opaque_srcover
  10M	42	4.28µs	5.59µs	5.11µs	6.01µs	15%	▂▂█▇█▂▁▆▁▇	8888	rotated_rects_aa_changing_transparent_srcover
  10M	48	4.24µs	4.33µs	4.58µs	6.46µs	15%	▁▁▁▁▁█▃▂▁▁	8888	rotated_rects_aa_changing_opaque_srcover
  10M	48	4.28µs	4.3µs	4.4µs	5.12µs	6%	▂▂▁▁▁▁▁▁▁█	8888	rotated_rects_aa_same_transparent_srcover
  10M	46	4.24µs	4.29µs	4.66µs	7.11µs	20%	▁▁▁▁▁▁▁▁▃█	8888	rotated_rects_aa_same_opaque_srcover
  10M	3	39.3µs	39.4µs	51.4µs	154µs	70%	█▁▁▁▁▁▁▁▁▁	8888	rectori
  10M	1	2.32ms	2.43ms	2.53ms	3.14ms	11%	▁▁▁▁▂▄█▃▅▁	8888	maskcolor
  10M	1	2.33ms	2.37ms	2.54ms	3.21ms	12%	▁▁▁▁▁▂█▅▆▁	8888	maskopaque
  10M	10	15.3µs	15.6µs	15.8µs	17.2µs	4%	█▅▃▂▂▂▁▁▁▁	8888	rrects_3_stroke_4
  10M	46	4.03µs	4.09µs	4.15µs	4.47µs	4%	█▄▆▂▂▂▁▁▁▁	8888	rrects_3
  10M	15	15.9µs	16.2µs	16.3µs	17.8µs	4%	█▄▃▂▂▂▁▁▁▁	8888	ovals_3_stroke_4
  10M	40	5.14µs	5.26µs	5.29µs	5.72µs	3%	█▅▃▂▂▁▂▂▁▁	8888	ovals_3
  10M	222	1.91µs	1.99µs	2.21µs	2.91µs	19%	▂▁▁▁▁▁▂▇▇█	8888	zeroradroundrect
  10M	462	3.9µs	3.96µs	4.23µs	5.22µs	12%	▆▄█▁▂▁▁▁▁▁	8888	arbroundrect
  10M	8	8.2µs	8.59µs	8.62µs	8.97µs	3%	▆▄█▄▅▃▁▆▄█	8888	merge_large
  10M	14	6.73µs	6.88µs	6.86µs	7.08µs	2%	▄█▁▂▄▂▅▄▂▅	8888	merge_small
  11M	2	221µs	234µs	237µs	263µs	5%	▄▃▃▃▄▃▂▁▇█	8888	displacement_full_large
  16M	1	387µs	416µs	427µs	471µs	7%	▇█▁▃▃▁▃▃▇▆	8888	displacement_alpha_large
  19M	1	512µs	521µs	528µs	594µs	5%	█▂▂▂▁▁▂▃▁▁	8888	displacement_zero_large
  19M	18	9.06µs	9.12µs	9.13µs	9.23µs	1%	█▃▃▃▄▃▆▁▅▅	8888	displacement_full_small
  19M	5	55.6µs	55.9µs	56.5µs	59.5µs	2%	█▃▂▁▁▁▁▁▅▁	8888	blurroundrect_WH[100x100]_cr[90]
  20M	1	229µs	233µs	235µs	254µs	3%	█▄▃▂▂▁▁▂▁▁	8888	GM_varied_text_clipped_no_lcd
  20M	1	270µs	271µs	272µs	278µs	1%	█▄▃▂▂▂▁▂▁▇	8888	GM_varied_text_ignorable_clip_no_lcd
  22M	1	1.96ms	2ms	2.06ms	2.45ms	7%	▂▂▁▁▁▁▁▃█▄	8888	GM_convex_poly_clip

BUG=skia:

Review URL: https://codereview.chromium.org/754733002

1 files changed, 29 insertions, 0 deletions

diff --git a/src/opts/SkColor_opts_SSE2.h b/src/opts/SkColor_opts_SSE2.h
index c1e41f02ae..c52fc1e876 100644
--- a/src/opts/SkColor_opts_SSE2.h
+++ b/src/opts/SkColor_opts_SSE2.h
@@ -203,5 +203,34 @@ static inline __m128i SkPixel32ToPixel16_ToU16_SSE2(const __m128i& src_pixel1,
     return d_pixel;
 }
 
+// Portable version SkBlendARGB32 is in SkColorPriv.h.
+static inline __m128i SkBlendARGB32_SSE2(const __m128i& src, const __m128i& dst,
+                                         const __m128i& aa) {
+    __m128i src_scale = SkAlpha255To256_SSE2(aa);
+    // SkAlpha255To256(255 - SkAlphaMul(SkGetPackedA32(src), src_scale))
+    __m128i dst_scale = SkGetPackedA32_SSE2(src);
+    dst_scale = _mm_mullo_epi16(dst_scale, src_scale);
+    dst_scale = _mm_srli_epi16(dst_scale, 8);
+    dst_scale = _mm_sub_epi32(_mm_set1_epi32(256), dst_scale);
+
+    __m128i result = SkAlphaMulQ_SSE2(src, src_scale);
+    return _mm_add_epi8(result, SkAlphaMulQ_SSE2(dst, dst_scale));
+}
+
+// Fast path for SkBlendARGB32_SSE2 with a constant alpha factor.
+static inline __m128i SkBlendARGB32_SSE2(const __m128i& src, const __m128i& dst,
+                                         const unsigned aa) {
+    unsigned alpha = SkAlpha255To256(aa);
+    __m128i src_scale = _mm_set1_epi32(alpha);
+    // SkAlpha255To256(255 - SkAlphaMul(SkGetPackedA32(src), src_scale))
+    __m128i dst_scale = SkGetPackedA32_SSE2(src);
+    dst_scale = _mm_mullo_epi16(dst_scale, src_scale);
+    dst_scale = _mm_srli_epi16(dst_scale, 8);
+    dst_scale = _mm_sub_epi32(_mm_set1_epi32(256), dst_scale);
+
+    __m128i result = SkAlphaMulQ_SSE2(src, alpha);
+    return _mm_add_epi8(result, SkAlphaMulQ_SSE2(dst, dst_scale));
+}
+
 #undef ASSERT_EQ
 #endif // SkColor_opts_SSE2_DEFINED