1 /*
2 * Copyright 2014 The Android Open Source Project
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8 #ifndef SkColor_opts_SSE2_DEFINED
9 #define SkColor_opts_SSE2_DEFINED
10
11 #include <emmintrin.h>
12
13 #define ASSERT_EQ(a,b) SkASSERT(0xffff == _mm_movemask_epi8(_mm_cmpeq_epi8((a), (b))))
14
15 // Because no _mm_mul_epi32() in SSE2, we emulate it here.
16 // Multiplies 4 32-bit integers from a by 4 32-bit intergers from b.
17 // The 4 multiplication results should be represented within 32-bit
18 // integers, otherwise they would be overflow.
Multiply32_SSE2(const __m128i & a,const __m128i & b)19 static inline __m128i Multiply32_SSE2(const __m128i& a, const __m128i& b) {
20 // Calculate results of a0 * b0 and a2 * b2.
21 __m128i r1 = _mm_mul_epu32(a, b);
22 // Calculate results of a1 * b1 and a3 * b3.
23 __m128i r2 = _mm_mul_epu32(_mm_srli_si128(a, 4), _mm_srli_si128(b, 4));
24 // Shuffle results to [63..0] and interleave the results.
25 __m128i r = _mm_unpacklo_epi32(_mm_shuffle_epi32(r1, _MM_SHUFFLE(0,0,2,0)),
26 _mm_shuffle_epi32(r2, _MM_SHUFFLE(0,0,2,0)));
27 return r;
28 }
29
SkAlpha255To256_SSE2(const __m128i & alpha)30 static inline __m128i SkAlpha255To256_SSE2(const __m128i& alpha) {
31 return _mm_add_epi32(alpha, _mm_set1_epi32(1));
32 }
33
34 // See #define SkAlphaMulAlpha(a, b) SkMulDiv255Round(a, b) in SkXfermode.cpp.
SkAlphaMulAlpha_SSE2(const __m128i & a,const __m128i & b)35 static inline __m128i SkAlphaMulAlpha_SSE2(const __m128i& a,
36 const __m128i& b) {
37 __m128i prod = _mm_mullo_epi16(a, b);
38 prod = _mm_add_epi32(prod, _mm_set1_epi32(128));
39 prod = _mm_add_epi32(prod, _mm_srli_epi32(prod, 8));
40 prod = _mm_srli_epi32(prod, 8);
41
42 return prod;
43 }
44
45 // Portable version SkAlphaMulQ is in SkColorPriv.h.
SkAlphaMulQ_SSE2(const __m128i & c,const __m128i & scale)46 static inline __m128i SkAlphaMulQ_SSE2(const __m128i& c, const __m128i& scale) {
47 const __m128i mask = _mm_set1_epi32(0xFF00FF);
48 __m128i s = _mm_or_si128(_mm_slli_epi32(scale, 16), scale);
49
50 // uint32_t rb = ((c & mask) * scale) >> 8
51 __m128i rb = _mm_and_si128(mask, c);
52 rb = _mm_mullo_epi16(rb, s);
53 rb = _mm_srli_epi16(rb, 8);
54
55 // uint32_t ag = ((c >> 8) & mask) * scale
56 __m128i ag = _mm_srli_epi16(c, 8);
57 ASSERT_EQ(ag, _mm_and_si128(mask, ag)); // ag = _mm_srli_epi16(c, 8) did this for us.
58 ag = _mm_mullo_epi16(ag, s);
59
60 // (rb & mask) | (ag & ~mask)
61 ASSERT_EQ(rb, _mm_and_si128(mask, rb)); // rb = _mm_srli_epi16(rb, 8) did this for us.
62 ag = _mm_andnot_si128(mask, ag);
63 return _mm_or_si128(rb, ag);
64 }
65
66 // Fast path for SkAlphaMulQ_SSE2 with a constant scale factor.
SkAlphaMulQ_SSE2(const __m128i & c,const unsigned scale)67 static inline __m128i SkAlphaMulQ_SSE2(const __m128i& c, const unsigned scale) {
68 const __m128i mask = _mm_set1_epi32(0xFF00FF);
69 __m128i s = _mm_set1_epi16(scale << 8); // Move scale factor to upper byte of word.
70
71 // With mulhi, red and blue values are already in the right place and
72 // don't need to be divided by 256.
73 __m128i rb = _mm_and_si128(mask, c);
74 rb = _mm_mulhi_epu16(rb, s);
75
76 __m128i ag = _mm_andnot_si128(mask, c);
77 ag = _mm_mulhi_epu16(ag, s); // Alpha and green values are in the higher byte of each word.
78 ag = _mm_andnot_si128(mask, ag);
79
80 return _mm_or_si128(rb, ag);
81 }
82
83 // Portable version SkFastFourByteInterp256 is in SkColorPriv.h.
SkFastFourByteInterp256_SSE2(const __m128i & src,const __m128i & dst,const unsigned src_scale)84 static inline __m128i SkFastFourByteInterp256_SSE2(const __m128i& src, const __m128i& dst, const unsigned src_scale) {
85 // Computes dst + (((src - dst)*src_scale)>>8)
86 const __m128i mask = _mm_set1_epi32(0x00FF00FF);
87
88 // Unpack the 16x8-bit source into 2 8x16-bit splayed halves.
89 __m128i src_rb = _mm_and_si128(mask, src);
90 __m128i src_ag = _mm_srli_epi16(src, 8);
91 __m128i dst_rb = _mm_and_si128(mask, dst);
92 __m128i dst_ag = _mm_srli_epi16(dst, 8);
93
94 // Compute scaled differences.
95 __m128i diff_rb = _mm_sub_epi16(src_rb, dst_rb);
96 __m128i diff_ag = _mm_sub_epi16(src_ag, dst_ag);
97 __m128i s = _mm_set1_epi16(src_scale);
98 diff_rb = _mm_mullo_epi16(diff_rb, s);
99 diff_ag = _mm_mullo_epi16(diff_ag, s);
100
101 // Pack the differences back together.
102 diff_rb = _mm_srli_epi16(diff_rb, 8);
103 diff_ag = _mm_andnot_si128(mask, diff_ag);
104 __m128i diff = _mm_or_si128(diff_rb, diff_ag);
105
106 // Add difference to destination.
107 return _mm_add_epi8(dst, diff);
108 }
109
110 // Portable version SkPMLerp is in SkColorPriv.h
SkPMLerp_SSE2(const __m128i & src,const __m128i & dst,const unsigned scale)111 static inline __m128i SkPMLerp_SSE2(const __m128i& src, const __m128i& dst, const unsigned scale) {
112 return SkFastFourByteInterp256_SSE2(src, dst, scale);
113 }
114
SkGetPackedA32_SSE2(const __m128i & src)115 static inline __m128i SkGetPackedA32_SSE2(const __m128i& src) {
116 #if SK_A32_SHIFT == 24 // It's very common (universal?) that alpha is the top byte.
117 return _mm_srli_epi32(src, 24); // You'd hope the compiler would remove the left shift then,
118 #else // but I've seen Clang just do a dumb left shift of zero. :(
119 __m128i a = _mm_slli_epi32(src, (24 - SK_A32_SHIFT));
120 return _mm_srli_epi32(a, 24);
121 #endif
122 }
123
SkGetPackedR32_SSE2(const __m128i & src)124 static inline __m128i SkGetPackedR32_SSE2(const __m128i& src) {
125 __m128i r = _mm_slli_epi32(src, (24 - SK_R32_SHIFT));
126 return _mm_srli_epi32(r, 24);
127 }
128
SkGetPackedG32_SSE2(const __m128i & src)129 static inline __m128i SkGetPackedG32_SSE2(const __m128i& src) {
130 __m128i g = _mm_slli_epi32(src, (24 - SK_G32_SHIFT));
131 return _mm_srli_epi32(g, 24);
132 }
133
SkGetPackedB32_SSE2(const __m128i & src)134 static inline __m128i SkGetPackedB32_SSE2(const __m128i& src) {
135 __m128i b = _mm_slli_epi32(src, (24 - SK_B32_SHIFT));
136 return _mm_srli_epi32(b, 24);
137 }
138
SkMul16ShiftRound_SSE2(const __m128i & a,const __m128i & b,int shift)139 static inline __m128i SkMul16ShiftRound_SSE2(const __m128i& a,
140 const __m128i& b, int shift) {
141 __m128i prod = _mm_mullo_epi16(a, b);
142 prod = _mm_add_epi16(prod, _mm_set1_epi16(1 << (shift - 1)));
143 prod = _mm_add_epi16(prod, _mm_srli_epi16(prod, shift));
144 prod = _mm_srli_epi16(prod, shift);
145
146 return prod;
147 }
148
SkPackRGB16_SSE2(const __m128i & r,const __m128i & g,const __m128i & b)149 static inline __m128i SkPackRGB16_SSE2(const __m128i& r,
150 const __m128i& g, const __m128i& b) {
151 __m128i dr = _mm_slli_epi16(r, SK_R16_SHIFT);
152 __m128i dg = _mm_slli_epi16(g, SK_G16_SHIFT);
153 __m128i db = _mm_slli_epi16(b, SK_B16_SHIFT);
154
155 __m128i c = _mm_or_si128(dr, dg);
156 return _mm_or_si128(c, db);
157 }
158
SkPackARGB32_SSE2(const __m128i & a,const __m128i & r,const __m128i & g,const __m128i & b)159 static inline __m128i SkPackARGB32_SSE2(const __m128i& a, const __m128i& r,
160 const __m128i& g, const __m128i& b) {
161 __m128i da = _mm_slli_epi32(a, SK_A32_SHIFT);
162 __m128i dr = _mm_slli_epi32(r, SK_R32_SHIFT);
163 __m128i dg = _mm_slli_epi32(g, SK_G32_SHIFT);
164 __m128i db = _mm_slli_epi32(b, SK_B32_SHIFT);
165
166 __m128i c = _mm_or_si128(da, dr);
167 c = _mm_or_si128(c, dg);
168 return _mm_or_si128(c, db);
169 }
170
SkPacked16ToR32_SSE2(const __m128i & src)171 static inline __m128i SkPacked16ToR32_SSE2(const __m128i& src) {
172 __m128i r = _mm_srli_epi32(src, SK_R16_SHIFT);
173 r = _mm_and_si128(r, _mm_set1_epi32(SK_R16_MASK));
174 r = _mm_or_si128(_mm_slli_epi32(r, (8 - SK_R16_BITS)),
175 _mm_srli_epi32(r, (2 * SK_R16_BITS - 8)));
176
177 return r;
178 }
179
SkPacked16ToG32_SSE2(const __m128i & src)180 static inline __m128i SkPacked16ToG32_SSE2(const __m128i& src) {
181 __m128i g = _mm_srli_epi32(src, SK_G16_SHIFT);
182 g = _mm_and_si128(g, _mm_set1_epi32(SK_G16_MASK));
183 g = _mm_or_si128(_mm_slli_epi32(g, (8 - SK_G16_BITS)),
184 _mm_srli_epi32(g, (2 * SK_G16_BITS - 8)));
185
186 return g;
187 }
188
SkPacked16ToB32_SSE2(const __m128i & src)189 static inline __m128i SkPacked16ToB32_SSE2(const __m128i& src) {
190 __m128i b = _mm_srli_epi32(src, SK_B16_SHIFT);
191 b = _mm_and_si128(b, _mm_set1_epi32(SK_B16_MASK));
192 b = _mm_or_si128(_mm_slli_epi32(b, (8 - SK_B16_BITS)),
193 _mm_srli_epi32(b, (2 * SK_B16_BITS - 8)));
194
195 return b;
196 }
197
SkPixel16ToPixel32_SSE2(const __m128i & src)198 static inline __m128i SkPixel16ToPixel32_SSE2(const __m128i& src) {
199 __m128i r = SkPacked16ToR32_SSE2(src);
200 __m128i g = SkPacked16ToG32_SSE2(src);
201 __m128i b = SkPacked16ToB32_SSE2(src);
202
203 return SkPackARGB32_SSE2(_mm_set1_epi32(0xFF), r, g, b);
204 }
205
SkPixel32ToPixel16_ToU16_SSE2(const __m128i & src_pixel1,const __m128i & src_pixel2)206 static inline __m128i SkPixel32ToPixel16_ToU16_SSE2(const __m128i& src_pixel1,
207 const __m128i& src_pixel2) {
208 // Calculate result r.
209 __m128i r1 = _mm_srli_epi32(src_pixel1,
210 SK_R32_SHIFT + (8 - SK_R16_BITS));
211 r1 = _mm_and_si128(r1, _mm_set1_epi32(SK_R16_MASK));
212 __m128i r2 = _mm_srli_epi32(src_pixel2,
213 SK_R32_SHIFT + (8 - SK_R16_BITS));
214 r2 = _mm_and_si128(r2, _mm_set1_epi32(SK_R16_MASK));
215 __m128i r = _mm_packs_epi32(r1, r2);
216
217 // Calculate result g.
218 __m128i g1 = _mm_srli_epi32(src_pixel1,
219 SK_G32_SHIFT + (8 - SK_G16_BITS));
220 g1 = _mm_and_si128(g1, _mm_set1_epi32(SK_G16_MASK));
221 __m128i g2 = _mm_srli_epi32(src_pixel2,
222 SK_G32_SHIFT + (8 - SK_G16_BITS));
223 g2 = _mm_and_si128(g2, _mm_set1_epi32(SK_G16_MASK));
224 __m128i g = _mm_packs_epi32(g1, g2);
225
226 // Calculate result b.
227 __m128i b1 = _mm_srli_epi32(src_pixel1,
228 SK_B32_SHIFT + (8 - SK_B16_BITS));
229 b1 = _mm_and_si128(b1, _mm_set1_epi32(SK_B16_MASK));
230 __m128i b2 = _mm_srli_epi32(src_pixel2,
231 SK_B32_SHIFT + (8 - SK_B16_BITS));
232 b2 = _mm_and_si128(b2, _mm_set1_epi32(SK_B16_MASK));
233 __m128i b = _mm_packs_epi32(b1, b2);
234
235 // Store 8 16-bit colors in dst.
236 __m128i d_pixel = SkPackRGB16_SSE2(r, g, b);
237
238 return d_pixel;
239 }
240
241 // Portable version is SkPMSrcOver in SkColorPriv.h.
SkPMSrcOver_SSE2(const __m128i & src,const __m128i & dst)242 static inline __m128i SkPMSrcOver_SSE2(const __m128i& src, const __m128i& dst) {
243 return _mm_add_epi32(src,
244 SkAlphaMulQ_SSE2(dst, _mm_sub_epi32(_mm_set1_epi32(256),
245 SkGetPackedA32_SSE2(src))));
246 }
247
248 // Fast path for SkBlendARGB32_SSE2 with a constant alpha factor.
SkBlendARGB32_SSE2(const __m128i & src,const __m128i & dst,const unsigned aa)249 static inline __m128i SkBlendARGB32_SSE2(const __m128i& src, const __m128i& dst,
250 const unsigned aa) {
251 unsigned alpha = SkAlpha255To256(aa);
252 __m128i src_scale = _mm_set1_epi16(alpha);
253 // SkAlphaMulInv256(SkGetPackedA32(src), src_scale)
254 __m128i dst_scale = SkGetPackedA32_SSE2(src);
255 // High words in dst_scale are 0, so it's safe to multiply with 16-bit src_scale.
256 dst_scale = _mm_mullo_epi16(dst_scale, src_scale);
257 dst_scale = _mm_sub_epi32(_mm_set1_epi32(0xFFFF), dst_scale);
258 dst_scale = _mm_add_epi32(dst_scale, _mm_srli_epi32(dst_scale, 8));
259 dst_scale = _mm_srli_epi32(dst_scale, 8);
260 // Duplicate scales into 2x16-bit pattern per pixel.
261 dst_scale = _mm_shufflelo_epi16(dst_scale, _MM_SHUFFLE(2, 2, 0, 0));
262 dst_scale = _mm_shufflehi_epi16(dst_scale, _MM_SHUFFLE(2, 2, 0, 0));
263
264 const __m128i mask = _mm_set1_epi32(0x00FF00FF);
265
266 // Unpack the 16x8-bit source/destination into 2 8x16-bit splayed halves.
267 __m128i src_rb = _mm_and_si128(mask, src);
268 __m128i src_ag = _mm_srli_epi16(src, 8);
269 __m128i dst_rb = _mm_and_si128(mask, dst);
270 __m128i dst_ag = _mm_srli_epi16(dst, 8);
271
272 // Scale them.
273 src_rb = _mm_mullo_epi16(src_rb, src_scale);
274 src_ag = _mm_mullo_epi16(src_ag, src_scale);
275 dst_rb = _mm_mullo_epi16(dst_rb, dst_scale);
276 dst_ag = _mm_mullo_epi16(dst_ag, dst_scale);
277
278 // Add the scaled source and destination.
279 dst_rb = _mm_add_epi16(src_rb, dst_rb);
280 dst_ag = _mm_add_epi16(src_ag, dst_ag);
281
282 // Unsplay the halves back together.
283 dst_rb = _mm_srli_epi16(dst_rb, 8);
284 dst_ag = _mm_andnot_si128(mask, dst_ag);
285 return _mm_or_si128(dst_rb, dst_ag);
286 }
287
288 #undef ASSERT_EQ
289 #endif // SkColor_opts_SSE2_DEFINED
290