1/* 2 * Copyright (c) 2017 The WebM project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11#include <arm_neon.h> 12 13#include "./vpx_config.h" 14#include "./vpx_dsp_rtcd.h" 15#include "vpx_dsp/txfm_common.h" 16#include "vpx_dsp/arm/mem_neon.h" 17#include "vpx_dsp/arm/transpose_neon.h" 18 19// Some builds of gcc 4.9.2 and .3 have trouble with some of the inline 20// functions. 21#if !defined(__clang__) && !defined(__ANDROID__) && defined(__GNUC__) && \ 22 __GNUC__ == 4 && __GNUC_MINOR__ == 9 && __GNUC_PATCHLEVEL__ < 4 23 24void vpx_fdct16x16_neon(const int16_t *input, tran_low_t *output, int stride) { 25 vpx_fdct16x16_c(input, output, stride); 26} 27 28#else 29 30static INLINE void load(const int16_t *a, int stride, int16x8_t *b /*[16]*/) { 31 b[0] = vld1q_s16(a); 32 a += stride; 33 b[1] = vld1q_s16(a); 34 a += stride; 35 b[2] = vld1q_s16(a); 36 a += stride; 37 b[3] = vld1q_s16(a); 38 a += stride; 39 b[4] = vld1q_s16(a); 40 a += stride; 41 b[5] = vld1q_s16(a); 42 a += stride; 43 b[6] = vld1q_s16(a); 44 a += stride; 45 b[7] = vld1q_s16(a); 46 a += stride; 47 b[8] = vld1q_s16(a); 48 a += stride; 49 b[9] = vld1q_s16(a); 50 a += stride; 51 b[10] = vld1q_s16(a); 52 a += stride; 53 b[11] = vld1q_s16(a); 54 a += stride; 55 b[12] = vld1q_s16(a); 56 a += stride; 57 b[13] = vld1q_s16(a); 58 a += stride; 59 b[14] = vld1q_s16(a); 60 a += stride; 61 b[15] = vld1q_s16(a); 62} 63 64// Store 8 16x8 values, assuming stride == 16. 65static INLINE void store(tran_low_t *a, const int16x8_t *b /*[8]*/) { 66 store_s16q_to_tran_low(a, b[0]); 67 a += 16; 68 store_s16q_to_tran_low(a, b[1]); 69 a += 16; 70 store_s16q_to_tran_low(a, b[2]); 71 a += 16; 72 store_s16q_to_tran_low(a, b[3]); 73 a += 16; 74 store_s16q_to_tran_low(a, b[4]); 75 a += 16; 76 store_s16q_to_tran_low(a, b[5]); 77 a += 16; 78 store_s16q_to_tran_low(a, b[6]); 79 a += 16; 80 store_s16q_to_tran_low(a, b[7]); 81} 82 83// Load step of each pass. Add and subtract clear across the input, requiring 84// all 16 values to be loaded. For the first pass it also multiplies by 4. 85 86// To maybe reduce register usage this could be combined with the load() step to 87// get the first 4 and last 4 values, cross those, then load the middle 8 values 88// and cross them. 89static INLINE void cross_input(const int16x8_t *a /*[16]*/, 90 int16x8_t *b /*[16]*/, const int pass) { 91 if (pass == 0) { 92 b[0] = vshlq_n_s16(vaddq_s16(a[0], a[15]), 2); 93 b[1] = vshlq_n_s16(vaddq_s16(a[1], a[14]), 2); 94 b[2] = vshlq_n_s16(vaddq_s16(a[2], a[13]), 2); 95 b[3] = vshlq_n_s16(vaddq_s16(a[3], a[12]), 2); 96 b[4] = vshlq_n_s16(vaddq_s16(a[4], a[11]), 2); 97 b[5] = vshlq_n_s16(vaddq_s16(a[5], a[10]), 2); 98 b[6] = vshlq_n_s16(vaddq_s16(a[6], a[9]), 2); 99 b[7] = vshlq_n_s16(vaddq_s16(a[7], a[8]), 2); 100 101 b[8] = vshlq_n_s16(vsubq_s16(a[7], a[8]), 2); 102 b[9] = vshlq_n_s16(vsubq_s16(a[6], a[9]), 2); 103 b[10] = vshlq_n_s16(vsubq_s16(a[5], a[10]), 2); 104 b[11] = vshlq_n_s16(vsubq_s16(a[4], a[11]), 2); 105 b[12] = vshlq_n_s16(vsubq_s16(a[3], a[12]), 2); 106 b[13] = vshlq_n_s16(vsubq_s16(a[2], a[13]), 2); 107 b[14] = vshlq_n_s16(vsubq_s16(a[1], a[14]), 2); 108 b[15] = vshlq_n_s16(vsubq_s16(a[0], a[15]), 2); 109 } else { 110 b[0] = vaddq_s16(a[0], a[15]); 111 b[1] = vaddq_s16(a[1], a[14]); 112 b[2] = vaddq_s16(a[2], a[13]); 113 b[3] = vaddq_s16(a[3], a[12]); 114 b[4] = vaddq_s16(a[4], a[11]); 115 b[5] = vaddq_s16(a[5], a[10]); 116 b[6] = vaddq_s16(a[6], a[9]); 117 b[7] = vaddq_s16(a[7], a[8]); 118 119 b[8] = vsubq_s16(a[7], a[8]); 120 b[9] = vsubq_s16(a[6], a[9]); 121 b[10] = vsubq_s16(a[5], a[10]); 122 b[11] = vsubq_s16(a[4], a[11]); 123 b[12] = vsubq_s16(a[3], a[12]); 124 b[13] = vsubq_s16(a[2], a[13]); 125 b[14] = vsubq_s16(a[1], a[14]); 126 b[15] = vsubq_s16(a[0], a[15]); 127 } 128} 129 130// Quarter round at the beginning of the second pass. Can't use vrshr (rounding) 131// because this only adds 1, not 1 << 2. 132static INLINE void partial_round_shift(int16x8_t *a /*[16]*/) { 133 const int16x8_t one = vdupq_n_s16(1); 134 a[0] = vshrq_n_s16(vaddq_s16(a[0], one), 2); 135 a[1] = vshrq_n_s16(vaddq_s16(a[1], one), 2); 136 a[2] = vshrq_n_s16(vaddq_s16(a[2], one), 2); 137 a[3] = vshrq_n_s16(vaddq_s16(a[3], one), 2); 138 a[4] = vshrq_n_s16(vaddq_s16(a[4], one), 2); 139 a[5] = vshrq_n_s16(vaddq_s16(a[5], one), 2); 140 a[6] = vshrq_n_s16(vaddq_s16(a[6], one), 2); 141 a[7] = vshrq_n_s16(vaddq_s16(a[7], one), 2); 142 a[8] = vshrq_n_s16(vaddq_s16(a[8], one), 2); 143 a[9] = vshrq_n_s16(vaddq_s16(a[9], one), 2); 144 a[10] = vshrq_n_s16(vaddq_s16(a[10], one), 2); 145 a[11] = vshrq_n_s16(vaddq_s16(a[11], one), 2); 146 a[12] = vshrq_n_s16(vaddq_s16(a[12], one), 2); 147 a[13] = vshrq_n_s16(vaddq_s16(a[13], one), 2); 148 a[14] = vshrq_n_s16(vaddq_s16(a[14], one), 2); 149 a[15] = vshrq_n_s16(vaddq_s16(a[15], one), 2); 150} 151 152// fdct_round_shift((a +/- b) * c) 153static INLINE void butterfly_one_coeff(const int16x8_t a, const int16x8_t b, 154 const tran_high_t c, int16x8_t *add, 155 int16x8_t *sub) { 156 const int32x4_t a0 = vmull_n_s16(vget_low_s16(a), c); 157 const int32x4_t a1 = vmull_n_s16(vget_high_s16(a), c); 158 const int32x4_t sum0 = vmlal_n_s16(a0, vget_low_s16(b), c); 159 const int32x4_t sum1 = vmlal_n_s16(a1, vget_high_s16(b), c); 160 const int32x4_t diff0 = vmlsl_n_s16(a0, vget_low_s16(b), c); 161 const int32x4_t diff1 = vmlsl_n_s16(a1, vget_high_s16(b), c); 162 const int16x4_t rounded0 = vqrshrn_n_s32(sum0, 14); 163 const int16x4_t rounded1 = vqrshrn_n_s32(sum1, 14); 164 const int16x4_t rounded2 = vqrshrn_n_s32(diff0, 14); 165 const int16x4_t rounded3 = vqrshrn_n_s32(diff1, 14); 166 *add = vcombine_s16(rounded0, rounded1); 167 *sub = vcombine_s16(rounded2, rounded3); 168} 169 170// fdct_round_shift(a * c0 +/- b * c1) 171static INLINE void butterfly_two_coeff(const int16x8_t a, const int16x8_t b, 172 const tran_coef_t c0, 173 const tran_coef_t c1, int16x8_t *add, 174 int16x8_t *sub) { 175 const int32x4_t a0 = vmull_n_s16(vget_low_s16(a), c0); 176 const int32x4_t a1 = vmull_n_s16(vget_high_s16(a), c0); 177 const int32x4_t a2 = vmull_n_s16(vget_low_s16(a), c1); 178 const int32x4_t a3 = vmull_n_s16(vget_high_s16(a), c1); 179 const int32x4_t sum0 = vmlal_n_s16(a2, vget_low_s16(b), c0); 180 const int32x4_t sum1 = vmlal_n_s16(a3, vget_high_s16(b), c0); 181 const int32x4_t diff0 = vmlsl_n_s16(a0, vget_low_s16(b), c1); 182 const int32x4_t diff1 = vmlsl_n_s16(a1, vget_high_s16(b), c1); 183 const int16x4_t rounded0 = vqrshrn_n_s32(sum0, 14); 184 const int16x4_t rounded1 = vqrshrn_n_s32(sum1, 14); 185 const int16x4_t rounded2 = vqrshrn_n_s32(diff0, 14); 186 const int16x4_t rounded3 = vqrshrn_n_s32(diff1, 14); 187 *add = vcombine_s16(rounded0, rounded1); 188 *sub = vcombine_s16(rounded2, rounded3); 189} 190 191// Transpose 8x8 to a new location. Don't use transpose_neon.h because those 192// are all in-place. 193static INLINE void transpose_8x8(const int16x8_t *a /*[8]*/, 194 int16x8_t *b /*[8]*/) { 195 // Swap 16 bit elements. 196 const int16x8x2_t c0 = vtrnq_s16(a[0], a[1]); 197 const int16x8x2_t c1 = vtrnq_s16(a[2], a[3]); 198 const int16x8x2_t c2 = vtrnq_s16(a[4], a[5]); 199 const int16x8x2_t c3 = vtrnq_s16(a[6], a[7]); 200 201 // Swap 32 bit elements. 202 const int32x4x2_t d0 = vtrnq_s32(vreinterpretq_s32_s16(c0.val[0]), 203 vreinterpretq_s32_s16(c1.val[0])); 204 const int32x4x2_t d1 = vtrnq_s32(vreinterpretq_s32_s16(c0.val[1]), 205 vreinterpretq_s32_s16(c1.val[1])); 206 const int32x4x2_t d2 = vtrnq_s32(vreinterpretq_s32_s16(c2.val[0]), 207 vreinterpretq_s32_s16(c3.val[0])); 208 const int32x4x2_t d3 = vtrnq_s32(vreinterpretq_s32_s16(c2.val[1]), 209 vreinterpretq_s32_s16(c3.val[1])); 210 211 // Swap 64 bit elements 212 const int16x8x2_t e0 = vpx_vtrnq_s64_to_s16(d0.val[0], d2.val[0]); 213 const int16x8x2_t e1 = vpx_vtrnq_s64_to_s16(d1.val[0], d3.val[0]); 214 const int16x8x2_t e2 = vpx_vtrnq_s64_to_s16(d0.val[1], d2.val[1]); 215 const int16x8x2_t e3 = vpx_vtrnq_s64_to_s16(d1.val[1], d3.val[1]); 216 217 b[0] = e0.val[0]; 218 b[1] = e1.val[0]; 219 b[2] = e2.val[0]; 220 b[3] = e3.val[0]; 221 b[4] = e0.val[1]; 222 b[5] = e1.val[1]; 223 b[6] = e2.val[1]; 224 b[7] = e3.val[1]; 225} 226 227// Main body of fdct16x16. 228static void dct_body(const int16x8_t *in /*[16]*/, int16x8_t *out /*[16]*/) { 229 int16x8_t s[8]; 230 int16x8_t x[4]; 231 int16x8_t step[8]; 232 233 // stage 1 234 // From fwd_txfm.c: Work on the first eight values; fdct8(input, 235 // even_results);" 236 s[0] = vaddq_s16(in[0], in[7]); 237 s[1] = vaddq_s16(in[1], in[6]); 238 s[2] = vaddq_s16(in[2], in[5]); 239 s[3] = vaddq_s16(in[3], in[4]); 240 s[4] = vsubq_s16(in[3], in[4]); 241 s[5] = vsubq_s16(in[2], in[5]); 242 s[6] = vsubq_s16(in[1], in[6]); 243 s[7] = vsubq_s16(in[0], in[7]); 244 245 // fdct4(step, step); 246 x[0] = vaddq_s16(s[0], s[3]); 247 x[1] = vaddq_s16(s[1], s[2]); 248 x[2] = vsubq_s16(s[1], s[2]); 249 x[3] = vsubq_s16(s[0], s[3]); 250 251 // out[0] = fdct_round_shift((x0 + x1) * cospi_16_64) 252 // out[8] = fdct_round_shift((x0 - x1) * cospi_16_64) 253 butterfly_one_coeff(x[0], x[1], cospi_16_64, &out[0], &out[8]); 254 // out[4] = fdct_round_shift(x3 * cospi_8_64 + x2 * cospi_24_64); 255 // out[12] = fdct_round_shift(x3 * cospi_24_64 - x2 * cospi_8_64); 256 butterfly_two_coeff(x[3], x[2], cospi_24_64, cospi_8_64, &out[4], &out[12]); 257 258 // Stage 2 259 // Re-using source s5/s6 260 // s5 = fdct_round_shift((s6 - s5) * cospi_16_64) 261 // s6 = fdct_round_shift((s6 + s5) * cospi_16_64) 262 butterfly_one_coeff(s[6], s[5], cospi_16_64, &s[6], &s[5]); 263 264 // Stage 3 265 x[0] = vaddq_s16(s[4], s[5]); 266 x[1] = vsubq_s16(s[4], s[5]); 267 x[2] = vsubq_s16(s[7], s[6]); 268 x[3] = vaddq_s16(s[7], s[6]); 269 270 // Stage 4 271 // out[2] = fdct_round_shift(x0 * cospi_28_64 + x3 * cospi_4_64) 272 // out[14] = fdct_round_shift(x3 * cospi_28_64 + x0 * -cospi_4_64) 273 butterfly_two_coeff(x[3], x[0], cospi_28_64, cospi_4_64, &out[2], &out[14]); 274 // out[6] = fdct_round_shift(x1 * cospi_12_64 + x2 * cospi_20_64) 275 // out[10] = fdct_round_shift(x2 * cospi_12_64 + x1 * -cospi_20_64) 276 butterfly_two_coeff(x[2], x[1], cospi_12_64, cospi_20_64, &out[10], &out[6]); 277 278 // step 2 279 // From fwd_txfm.c: Work on the next eight values; step1 -> odd_results" 280 // That file distinguished between "in_high" and "step1" but the only 281 // difference is that "in_high" is the first 8 values and "step 1" is the 282 // second. Here, since they are all in one array, "step1" values are += 8. 283 284 // step2[2] = fdct_round_shift((step1[5] - step1[2]) * cospi_16_64) 285 // step2[3] = fdct_round_shift((step1[4] - step1[3]) * cospi_16_64) 286 // step2[4] = fdct_round_shift((step1[4] + step1[3]) * cospi_16_64) 287 // step2[5] = fdct_round_shift((step1[5] + step1[2]) * cospi_16_64) 288 butterfly_one_coeff(in[13], in[10], cospi_16_64, &s[5], &s[2]); 289 butterfly_one_coeff(in[12], in[11], cospi_16_64, &s[4], &s[3]); 290 291 // step 3 292 s[0] = vaddq_s16(in[8], s[3]); 293 s[1] = vaddq_s16(in[9], s[2]); 294 x[0] = vsubq_s16(in[9], s[2]); 295 x[1] = vsubq_s16(in[8], s[3]); 296 x[2] = vsubq_s16(in[15], s[4]); 297 x[3] = vsubq_s16(in[14], s[5]); 298 s[6] = vaddq_s16(in[14], s[5]); 299 s[7] = vaddq_s16(in[15], s[4]); 300 301 // step 4 302 // step2[1] = fdct_round_shift(step3[1] *-cospi_8_64 + step3[6] * cospi_24_64) 303 // step2[6] = fdct_round_shift(step3[1] * cospi_24_64 + step3[6] * cospi_8_64) 304 butterfly_two_coeff(s[6], s[1], cospi_24_64, cospi_8_64, &s[6], &s[1]); 305 306 // step2[2] = fdct_round_shift(step3[2] * cospi_24_64 + step3[5] * cospi_8_64) 307 // step2[5] = fdct_round_shift(step3[2] * cospi_8_64 - step3[5] * cospi_24_64) 308 butterfly_two_coeff(x[0], x[3], cospi_8_64, cospi_24_64, &s[2], &s[5]); 309 310 // step 5 311 step[0] = vaddq_s16(s[0], s[1]); 312 step[1] = vsubq_s16(s[0], s[1]); 313 step[2] = vaddq_s16(x[1], s[2]); 314 step[3] = vsubq_s16(x[1], s[2]); 315 step[4] = vsubq_s16(x[2], s[5]); 316 step[5] = vaddq_s16(x[2], s[5]); 317 step[6] = vsubq_s16(s[7], s[6]); 318 step[7] = vaddq_s16(s[7], s[6]); 319 320 // step 6 321 // out[1] = fdct_round_shift(step1[0] * cospi_30_64 + step1[7] * cospi_2_64) 322 // out[9] = fdct_round_shift(step1[1] * cospi_14_64 + step1[6] * cospi_18_64) 323 // out[5] = fdct_round_shift(step1[2] * cospi_22_64 + step1[5] * cospi_10_64) 324 // out[13] = fdct_round_shift(step1[3] * cospi_6_64 + step1[4] * cospi_26_64) 325 // out[3] = fdct_round_shift(step1[3] * -cospi_26_64 + step1[4] * cospi_6_64) 326 // out[11] = fdct_round_shift(step1[2] * -cospi_10_64 + step1[5] * 327 // cospi_22_64) 328 // out[7] = fdct_round_shift(step1[1] * -cospi_18_64 + step1[6] * cospi_14_64) 329 // out[15] = fdct_round_shift(step1[0] * -cospi_2_64 + step1[7] * cospi_30_64) 330 butterfly_two_coeff(step[6], step[1], cospi_14_64, cospi_18_64, &out[9], 331 &out[7]); 332 butterfly_two_coeff(step[7], step[0], cospi_30_64, cospi_2_64, &out[1], 333 &out[15]); 334 butterfly_two_coeff(step[4], step[3], cospi_6_64, cospi_26_64, &out[13], 335 &out[3]); 336 butterfly_two_coeff(step[5], step[2], cospi_22_64, cospi_10_64, &out[5], 337 &out[11]); 338} 339 340void vpx_fdct16x16_neon(const int16_t *input, tran_low_t *output, int stride) { 341 int16x8_t temp0[16]; 342 int16x8_t temp1[16]; 343 int16x8_t temp2[16]; 344 int16x8_t temp3[16]; 345 346 // Left half. 347 load(input, stride, temp0); 348 cross_input(temp0, temp1, 0); 349 dct_body(temp1, temp0); 350 351 // Right half. 352 load(input + 8, stride, temp1); 353 cross_input(temp1, temp2, 0); 354 dct_body(temp2, temp1); 355 356 // Transpose top left and top right quarters into one contiguous location to 357 // process to the top half. 358 transpose_8x8(&temp0[0], &temp2[0]); 359 transpose_8x8(&temp1[0], &temp2[8]); 360 partial_round_shift(temp2); 361 cross_input(temp2, temp3, 1); 362 dct_body(temp3, temp2); 363 transpose_s16_8x8(&temp2[0], &temp2[1], &temp2[2], &temp2[3], &temp2[4], 364 &temp2[5], &temp2[6], &temp2[7]); 365 transpose_s16_8x8(&temp2[8], &temp2[9], &temp2[10], &temp2[11], &temp2[12], 366 &temp2[13], &temp2[14], &temp2[15]); 367 store(output, temp2); 368 store(output + 8, temp2 + 8); 369 output += 8 * 16; 370 371 // Transpose bottom left and bottom right quarters into one contiguous 372 // location to process to the bottom half. 373 transpose_8x8(&temp0[8], &temp1[0]); 374 transpose_s16_8x8(&temp1[8], &temp1[9], &temp1[10], &temp1[11], &temp1[12], 375 &temp1[13], &temp1[14], &temp1[15]); 376 partial_round_shift(temp1); 377 cross_input(temp1, temp0, 1); 378 dct_body(temp0, temp1); 379 transpose_s16_8x8(&temp1[0], &temp1[1], &temp1[2], &temp1[3], &temp1[4], 380 &temp1[5], &temp1[6], &temp1[7]); 381 transpose_s16_8x8(&temp1[8], &temp1[9], &temp1[10], &temp1[11], &temp1[12], 382 &temp1[13], &temp1[14], &temp1[15]); 383 store(output, temp1); 384 store(output + 8, temp1 + 8); 385} 386#endif // !defined(__clang__) && !defined(__ANDROID__) && defined(__GNUC__) && 387 // __GNUC__ == 4 && __GNUC_MINOR__ == 9 && __GNUC_PATCHLEVEL__ < 4 388