1 // Copyright 2015 Google Inc. All Rights Reserved. 2 // 3 // Use of this source code is governed by a BSD-style license 4 // that can be found in the COPYING file in the root of the source 5 // tree. An additional intellectual property rights grant can be found 6 // in the file PATENTS. All contributing project authors may 7 // be found in the AUTHORS file in the root of the source tree. 8 // ----------------------------------------------------------------------------- 9 // 10 // SSE2 Rescaling functions 11 // 12 // Author: Skal (pascal.massimino (at) gmail.com) 13 14 #include "src/dsp/dsp.h" 15 16 #if defined(WEBP_USE_SSE2) && !defined(WEBP_REDUCE_SIZE) 17 #include <emmintrin.h> 18 19 #include <assert.h> 20 #include "src/utils/rescaler_utils.h" 21 #include "src/utils/utils.h" 22 23 //------------------------------------------------------------------------------ 24 // Implementations of critical functions ImportRow / ExportRow 25 26 #define ROUNDER (WEBP_RESCALER_ONE >> 1) 27 #define MULT_FIX(x, y) (((uint64_t)(x) * (y) + ROUNDER) >> WEBP_RESCALER_RFIX) 28 #define MULT_FIX_FLOOR(x, y) (((uint64_t)(x) * (y)) >> WEBP_RESCALER_RFIX) 29 30 // input: 8 bytes ABCDEFGH -> output: A0E0B0F0C0G0D0H0 31 static void LoadTwoPixels_SSE2(const uint8_t* const src, __m128i* out) { 32 const __m128i zero = _mm_setzero_si128(); 33 const __m128i A = _mm_loadl_epi64((const __m128i*)(src)); // ABCDEFGH 34 const __m128i B = _mm_unpacklo_epi8(A, zero); // A0B0C0D0E0F0G0H0 35 const __m128i C = _mm_srli_si128(B, 8); // E0F0G0H0 36 *out = _mm_unpacklo_epi16(B, C); 37 } 38 39 // input: 8 bytes ABCDEFGH -> output: A0B0C0D0E0F0G0H0 40 static void LoadEightPixels_SSE2(const uint8_t* const src, __m128i* out) { 41 const __m128i zero = _mm_setzero_si128(); 42 const __m128i A = _mm_loadl_epi64((const __m128i*)(src)); // ABCDEFGH 43 *out = _mm_unpacklo_epi8(A, zero); 44 } 45 46 static void RescalerImportRowExpand_SSE2(WebPRescaler* const wrk, 47 const uint8_t* src) { 48 rescaler_t* frow = wrk->frow; 49 const rescaler_t* const frow_end = frow + wrk->dst_width * wrk->num_channels; 50 const int x_add = wrk->x_add; 51 int accum = x_add; 52 __m128i cur_pixels; 53 54 // SSE2 implementation only works with 16b signed arithmetic at max. 55 if (wrk->src_width < 8 || accum >= (1 << 15)) { 56 WebPRescalerImportRowExpand_C(wrk, src); 57 return; 58 } 59 60 assert(!WebPRescalerInputDone(wrk)); 61 assert(wrk->x_expand); 62 if (wrk->num_channels == 4) { 63 LoadTwoPixels_SSE2(src, &cur_pixels); 64 src += 4; 65 while (1) { 66 const __m128i mult = _mm_set1_epi32(((x_add - accum) << 16) | accum); 67 const __m128i out = _mm_madd_epi16(cur_pixels, mult); 68 _mm_storeu_si128((__m128i*)frow, out); 69 frow += 4; 70 if (frow >= frow_end) break; 71 accum -= wrk->x_sub; 72 if (accum < 0) { 73 LoadTwoPixels_SSE2(src, &cur_pixels); 74 src += 4; 75 accum += x_add; 76 } 77 } 78 } else { 79 int left; 80 const uint8_t* const src_limit = src + wrk->src_width - 8; 81 LoadEightPixels_SSE2(src, &cur_pixels); 82 src += 7; 83 left = 7; 84 while (1) { 85 const __m128i mult = _mm_cvtsi32_si128(((x_add - accum) << 16) | accum); 86 const __m128i out = _mm_madd_epi16(cur_pixels, mult); 87 assert(sizeof(*frow) == sizeof(uint32_t)); 88 WebPUint32ToMem((uint8_t*)frow, _mm_cvtsi128_si32(out)); 89 frow += 1; 90 if (frow >= frow_end) break; 91 accum -= wrk->x_sub; 92 if (accum < 0) { 93 if (--left) { 94 cur_pixels = _mm_srli_si128(cur_pixels, 2); 95 } else if (src <= src_limit) { 96 LoadEightPixels_SSE2(src, &cur_pixels); 97 src += 7; 98 left = 7; 99 } else { // tail 100 cur_pixels = _mm_srli_si128(cur_pixels, 2); 101 cur_pixels = _mm_insert_epi16(cur_pixels, src[1], 1); 102 src += 1; 103 left = 1; 104 } 105 accum += x_add; 106 } 107 } 108 } 109 assert(accum == 0); 110 } 111 112 static void RescalerImportRowShrink_SSE2(WebPRescaler* const wrk, 113 const uint8_t* src) { 114 const int x_sub = wrk->x_sub; 115 int accum = 0; 116 const __m128i zero = _mm_setzero_si128(); 117 const __m128i mult0 = _mm_set1_epi16(x_sub); 118 const __m128i mult1 = _mm_set1_epi32(wrk->fx_scale); 119 const __m128i rounder = _mm_set_epi32(0, ROUNDER, 0, ROUNDER); 120 __m128i sum = zero; 121 rescaler_t* frow = wrk->frow; 122 const rescaler_t* const frow_end = wrk->frow + 4 * wrk->dst_width; 123 124 if (wrk->num_channels != 4 || wrk->x_add > (x_sub << 7)) { 125 WebPRescalerImportRowShrink_C(wrk, src); 126 return; 127 } 128 assert(!WebPRescalerInputDone(wrk)); 129 assert(!wrk->x_expand); 130 131 for (; frow < frow_end; frow += 4) { 132 __m128i base = zero; 133 accum += wrk->x_add; 134 while (accum > 0) { 135 const __m128i A = _mm_cvtsi32_si128(WebPMemToUint32(src)); 136 src += 4; 137 base = _mm_unpacklo_epi8(A, zero); 138 // To avoid overflow, we need: base * x_add / x_sub < 32768 139 // => x_add < x_sub << 7. That's a 1/128 reduction ratio limit. 140 sum = _mm_add_epi16(sum, base); 141 accum -= x_sub; 142 } 143 { // Emit next horizontal pixel. 144 const __m128i mult = _mm_set1_epi16(-accum); 145 const __m128i frac0 = _mm_mullo_epi16(base, mult); // 16b x 16b -> 32b 146 const __m128i frac1 = _mm_mulhi_epu16(base, mult); 147 const __m128i frac = _mm_unpacklo_epi16(frac0, frac1); // frac is 32b 148 const __m128i A0 = _mm_mullo_epi16(sum, mult0); 149 const __m128i A1 = _mm_mulhi_epu16(sum, mult0); 150 const __m128i B0 = _mm_unpacklo_epi16(A0, A1); // sum * x_sub 151 const __m128i frow_out = _mm_sub_epi32(B0, frac); // sum * x_sub - frac 152 const __m128i D0 = _mm_srli_epi64(frac, 32); 153 const __m128i D1 = _mm_mul_epu32(frac, mult1); // 32b x 16b -> 64b 154 const __m128i D2 = _mm_mul_epu32(D0, mult1); 155 const __m128i E1 = _mm_add_epi64(D1, rounder); 156 const __m128i E2 = _mm_add_epi64(D2, rounder); 157 const __m128i F1 = _mm_shuffle_epi32(E1, 1 | (3 << 2)); 158 const __m128i F2 = _mm_shuffle_epi32(E2, 1 | (3 << 2)); 159 const __m128i G = _mm_unpacklo_epi32(F1, F2); 160 sum = _mm_packs_epi32(G, zero); 161 _mm_storeu_si128((__m128i*)frow, frow_out); 162 } 163 } 164 assert(accum == 0); 165 } 166 167 //------------------------------------------------------------------------------ 168 // Row export 169 170 // load *src as epi64, multiply by mult and store result in [out0 ... out3] 171 static WEBP_INLINE void LoadDispatchAndMult_SSE2(const rescaler_t* const src, 172 const __m128i* const mult, 173 __m128i* const out0, 174 __m128i* const out1, 175 __m128i* const out2, 176 __m128i* const out3) { 177 const __m128i A0 = _mm_loadu_si128((const __m128i*)(src + 0)); 178 const __m128i A1 = _mm_loadu_si128((const __m128i*)(src + 4)); 179 const __m128i A2 = _mm_srli_epi64(A0, 32); 180 const __m128i A3 = _mm_srli_epi64(A1, 32); 181 if (mult != NULL) { 182 *out0 = _mm_mul_epu32(A0, *mult); 183 *out1 = _mm_mul_epu32(A1, *mult); 184 *out2 = _mm_mul_epu32(A2, *mult); 185 *out3 = _mm_mul_epu32(A3, *mult); 186 } else { 187 *out0 = A0; 188 *out1 = A1; 189 *out2 = A2; 190 *out3 = A3; 191 } 192 } 193 194 static WEBP_INLINE void ProcessRow_SSE2(const __m128i* const A0, 195 const __m128i* const A1, 196 const __m128i* const A2, 197 const __m128i* const A3, 198 const __m128i* const mult, 199 uint8_t* const dst) { 200 const __m128i rounder = _mm_set_epi32(0, ROUNDER, 0, ROUNDER); 201 const __m128i mask = _mm_set_epi32(0xffffffffu, 0, 0xffffffffu, 0); 202 const __m128i B0 = _mm_mul_epu32(*A0, *mult); 203 const __m128i B1 = _mm_mul_epu32(*A1, *mult); 204 const __m128i B2 = _mm_mul_epu32(*A2, *mult); 205 const __m128i B3 = _mm_mul_epu32(*A3, *mult); 206 const __m128i C0 = _mm_add_epi64(B0, rounder); 207 const __m128i C1 = _mm_add_epi64(B1, rounder); 208 const __m128i C2 = _mm_add_epi64(B2, rounder); 209 const __m128i C3 = _mm_add_epi64(B3, rounder); 210 const __m128i D0 = _mm_srli_epi64(C0, WEBP_RESCALER_RFIX); 211 const __m128i D1 = _mm_srli_epi64(C1, WEBP_RESCALER_RFIX); 212 #if (WEBP_RESCALER_RFIX < 32) 213 const __m128i D2 = 214 _mm_and_si128(_mm_slli_epi64(C2, 32 - WEBP_RESCALER_RFIX), mask); 215 const __m128i D3 = 216 _mm_and_si128(_mm_slli_epi64(C3, 32 - WEBP_RESCALER_RFIX), mask); 217 #else 218 const __m128i D2 = _mm_and_si128(C2, mask); 219 const __m128i D3 = _mm_and_si128(C3, mask); 220 #endif 221 const __m128i E0 = _mm_or_si128(D0, D2); 222 const __m128i E1 = _mm_or_si128(D1, D3); 223 const __m128i F = _mm_packs_epi32(E0, E1); 224 const __m128i G = _mm_packus_epi16(F, F); 225 _mm_storel_epi64((__m128i*)dst, G); 226 } 227 228 static void RescalerExportRowExpand_SSE2(WebPRescaler* const wrk) { 229 int x_out; 230 uint8_t* const dst = wrk->dst; 231 rescaler_t* const irow = wrk->irow; 232 const int x_out_max = wrk->dst_width * wrk->num_channels; 233 const rescaler_t* const frow = wrk->frow; 234 const __m128i mult = _mm_set_epi32(0, wrk->fy_scale, 0, wrk->fy_scale); 235 236 assert(!WebPRescalerOutputDone(wrk)); 237 assert(wrk->y_accum <= 0 && wrk->y_sub + wrk->y_accum >= 0); 238 assert(wrk->y_expand); 239 if (wrk->y_accum == 0) { 240 for (x_out = 0; x_out + 8 <= x_out_max; x_out += 8) { 241 __m128i A0, A1, A2, A3; 242 LoadDispatchAndMult_SSE2(frow + x_out, NULL, &A0, &A1, &A2, &A3); 243 ProcessRow_SSE2(&A0, &A1, &A2, &A3, &mult, dst + x_out); 244 } 245 for (; x_out < x_out_max; ++x_out) { 246 const uint32_t J = frow[x_out]; 247 const int v = (int)MULT_FIX(J, wrk->fy_scale); 248 dst[x_out] = (v > 255) ? 255u : (uint8_t)v; 249 } 250 } else { 251 const uint32_t B = WEBP_RESCALER_FRAC(-wrk->y_accum, wrk->y_sub); 252 const uint32_t A = (uint32_t)(WEBP_RESCALER_ONE - B); 253 const __m128i mA = _mm_set_epi32(0, A, 0, A); 254 const __m128i mB = _mm_set_epi32(0, B, 0, B); 255 const __m128i rounder = _mm_set_epi32(0, ROUNDER, 0, ROUNDER); 256 for (x_out = 0; x_out + 8 <= x_out_max; x_out += 8) { 257 __m128i A0, A1, A2, A3, B0, B1, B2, B3; 258 LoadDispatchAndMult_SSE2(frow + x_out, &mA, &A0, &A1, &A2, &A3); 259 LoadDispatchAndMult_SSE2(irow + x_out, &mB, &B0, &B1, &B2, &B3); 260 { 261 const __m128i C0 = _mm_add_epi64(A0, B0); 262 const __m128i C1 = _mm_add_epi64(A1, B1); 263 const __m128i C2 = _mm_add_epi64(A2, B2); 264 const __m128i C3 = _mm_add_epi64(A3, B3); 265 const __m128i D0 = _mm_add_epi64(C0, rounder); 266 const __m128i D1 = _mm_add_epi64(C1, rounder); 267 const __m128i D2 = _mm_add_epi64(C2, rounder); 268 const __m128i D3 = _mm_add_epi64(C3, rounder); 269 const __m128i E0 = _mm_srli_epi64(D0, WEBP_RESCALER_RFIX); 270 const __m128i E1 = _mm_srli_epi64(D1, WEBP_RESCALER_RFIX); 271 const __m128i E2 = _mm_srli_epi64(D2, WEBP_RESCALER_RFIX); 272 const __m128i E3 = _mm_srli_epi64(D3, WEBP_RESCALER_RFIX); 273 ProcessRow_SSE2(&E0, &E1, &E2, &E3, &mult, dst + x_out); 274 } 275 } 276 for (; x_out < x_out_max; ++x_out) { 277 const uint64_t I = (uint64_t)A * frow[x_out] 278 + (uint64_t)B * irow[x_out]; 279 const uint32_t J = (uint32_t)((I + ROUNDER) >> WEBP_RESCALER_RFIX); 280 const int v = (int)MULT_FIX(J, wrk->fy_scale); 281 dst[x_out] = (v > 255) ? 255u : (uint8_t)v; 282 } 283 } 284 } 285 286 static void RescalerExportRowShrink_SSE2(WebPRescaler* const wrk) { 287 int x_out; 288 uint8_t* const dst = wrk->dst; 289 rescaler_t* const irow = wrk->irow; 290 const int x_out_max = wrk->dst_width * wrk->num_channels; 291 const rescaler_t* const frow = wrk->frow; 292 const uint32_t yscale = wrk->fy_scale * (-wrk->y_accum); 293 assert(!WebPRescalerOutputDone(wrk)); 294 assert(wrk->y_accum <= 0); 295 assert(!wrk->y_expand); 296 if (yscale) { 297 const int scale_xy = wrk->fxy_scale; 298 const __m128i mult_xy = _mm_set_epi32(0, scale_xy, 0, scale_xy); 299 const __m128i mult_y = _mm_set_epi32(0, yscale, 0, yscale); 300 for (x_out = 0; x_out + 8 <= x_out_max; x_out += 8) { 301 __m128i A0, A1, A2, A3, B0, B1, B2, B3; 302 LoadDispatchAndMult_SSE2(irow + x_out, NULL, &A0, &A1, &A2, &A3); 303 LoadDispatchAndMult_SSE2(frow + x_out, &mult_y, &B0, &B1, &B2, &B3); 304 { 305 const __m128i D0 = _mm_srli_epi64(B0, WEBP_RESCALER_RFIX); // = frac 306 const __m128i D1 = _mm_srli_epi64(B1, WEBP_RESCALER_RFIX); 307 const __m128i D2 = _mm_srli_epi64(B2, WEBP_RESCALER_RFIX); 308 const __m128i D3 = _mm_srli_epi64(B3, WEBP_RESCALER_RFIX); 309 const __m128i E0 = _mm_sub_epi64(A0, D0); // irow[x] - frac 310 const __m128i E1 = _mm_sub_epi64(A1, D1); 311 const __m128i E2 = _mm_sub_epi64(A2, D2); 312 const __m128i E3 = _mm_sub_epi64(A3, D3); 313 const __m128i F2 = _mm_slli_epi64(D2, 32); 314 const __m128i F3 = _mm_slli_epi64(D3, 32); 315 const __m128i G0 = _mm_or_si128(D0, F2); 316 const __m128i G1 = _mm_or_si128(D1, F3); 317 _mm_storeu_si128((__m128i*)(irow + x_out + 0), G0); 318 _mm_storeu_si128((__m128i*)(irow + x_out + 4), G1); 319 ProcessRow_SSE2(&E0, &E1, &E2, &E3, &mult_xy, dst + x_out); 320 } 321 } 322 for (; x_out < x_out_max; ++x_out) { 323 const uint32_t frac = (int)MULT_FIX_FLOOR(frow[x_out], yscale); 324 const int v = (int)MULT_FIX(irow[x_out] - frac, wrk->fxy_scale); 325 dst[x_out] = (v > 255) ? 255u : (uint8_t)v; 326 irow[x_out] = frac; // new fractional start 327 } 328 } else { 329 const uint32_t scale = wrk->fxy_scale; 330 const __m128i mult = _mm_set_epi32(0, scale, 0, scale); 331 const __m128i zero = _mm_setzero_si128(); 332 for (x_out = 0; x_out + 8 <= x_out_max; x_out += 8) { 333 __m128i A0, A1, A2, A3; 334 LoadDispatchAndMult_SSE2(irow + x_out, NULL, &A0, &A1, &A2, &A3); 335 _mm_storeu_si128((__m128i*)(irow + x_out + 0), zero); 336 _mm_storeu_si128((__m128i*)(irow + x_out + 4), zero); 337 ProcessRow_SSE2(&A0, &A1, &A2, &A3, &mult, dst + x_out); 338 } 339 for (; x_out < x_out_max; ++x_out) { 340 const int v = (int)MULT_FIX(irow[x_out], scale); 341 dst[x_out] = (v > 255) ? 255u : (uint8_t)v; 342 irow[x_out] = 0; 343 } 344 } 345 } 346 347 #undef MULT_FIX_FLOOR 348 #undef MULT_FIX 349 #undef ROUNDER 350 351 //------------------------------------------------------------------------------ 352 353 extern void WebPRescalerDspInitSSE2(void); 354 355 WEBP_TSAN_IGNORE_FUNCTION void WebPRescalerDspInitSSE2(void) { 356 WebPRescalerImportRowExpand = RescalerImportRowExpand_SSE2; 357 WebPRescalerImportRowShrink = RescalerImportRowShrink_SSE2; 358 WebPRescalerExportRowExpand = RescalerExportRowExpand_SSE2; 359 WebPRescalerExportRowShrink = RescalerExportRowShrink_SSE2; 360 } 361 362 #else // !WEBP_USE_SSE2 363 364 WEBP_DSP_INIT_STUB(WebPRescalerDspInitSSE2) 365 366 #endif // WEBP_USE_SSE2 367
