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Diffstat (limited to 'third_party/aom/av1/common/x86/cfl_avx2.c')
| -rw-r--r-- | third_party/aom/av1/common/x86/cfl_avx2.c | 491 |
1 files changed, 491 insertions, 0 deletions
diff --git a/third_party/aom/av1/common/x86/cfl_avx2.c b/third_party/aom/av1/common/x86/cfl_avx2.c new file mode 100644 index 000000000..a8bfdcce6 --- /dev/null +++ b/third_party/aom/av1/common/x86/cfl_avx2.c @@ -0,0 +1,491 @@ +/* + * Copyright (c) 2017, Alliance for Open Media. All rights reserved + * + * This source code is subject to the terms of the BSD 2 Clause License and + * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License + * was not distributed with this source code in the LICENSE file, you can + * obtain it at www.aomedia.org/license/software. If the Alliance for Open + * Media Patent License 1.0 was not distributed with this source code in the + * PATENTS file, you can obtain it at www.aomedia.org/license/patent. + */ +#include <immintrin.h> + +#include "config/av1_rtcd.h" + +#include "av1/common/cfl.h" + +#include "av1/common/x86/cfl_simd.h" + +#define CFL_GET_SUBSAMPLE_FUNCTION_AVX2(sub, bd) \ + CFL_SUBSAMPLE(avx2, sub, bd, 32, 32) \ + CFL_SUBSAMPLE(avx2, sub, bd, 32, 16) \ + CFL_SUBSAMPLE(avx2, sub, bd, 32, 8) \ + cfl_subsample_##bd##_fn cfl_get_luma_subsampling_##sub##_##bd##_avx2( \ + TX_SIZE tx_size) { \ + static const cfl_subsample_##bd##_fn subfn_##sub[TX_SIZES_ALL] = { \ + subsample_##bd##_##sub##_4x4_ssse3, /* 4x4 */ \ + subsample_##bd##_##sub##_8x8_ssse3, /* 8x8 */ \ + subsample_##bd##_##sub##_16x16_ssse3, /* 16x16 */ \ + subsample_##bd##_##sub##_32x32_avx2, /* 32x32 */ \ + cfl_subsample_##bd##_null, /* 64x64 (invalid CFL size) */ \ + subsample_##bd##_##sub##_4x8_ssse3, /* 4x8 */ \ + subsample_##bd##_##sub##_8x4_ssse3, /* 8x4 */ \ + subsample_##bd##_##sub##_8x16_ssse3, /* 8x16 */ \ + subsample_##bd##_##sub##_16x8_ssse3, /* 16x8 */ \ + subsample_##bd##_##sub##_16x32_ssse3, /* 16x32 */ \ + subsample_##bd##_##sub##_32x16_avx2, /* 32x16 */ \ + cfl_subsample_##bd##_null, /* 32x64 (invalid CFL size) */ \ + cfl_subsample_##bd##_null, /* 64x32 (invalid CFL size) */ \ + subsample_##bd##_##sub##_4x16_ssse3, /* 4x16 */ \ + subsample_##bd##_##sub##_16x4_ssse3, /* 16x4 */ \ + subsample_##bd##_##sub##_8x32_ssse3, /* 8x32 */ \ + subsample_##bd##_##sub##_32x8_avx2, /* 32x8 */ \ + cfl_subsample_##bd##_null, /* 16x64 (invalid CFL size) */ \ + cfl_subsample_##bd##_null, /* 64x16 (invalid CFL size) */ \ + }; \ + return subfn_##sub[tx_size]; \ + } + +/** + * Adds 4 pixels (in a 2x2 grid) and multiplies them by 2. Resulting in a more + * precise version of a box filter 4:2:0 pixel subsampling in Q3. + * + * The CfL prediction buffer is always of size CFL_BUF_SQUARE. However, the + * active area is specified using width and height. + * + * Note: We don't need to worry about going over the active area, as long as we + * stay inside the CfL prediction buffer. + * + * Note: For 4:2:0 luma subsampling, the width will never be greater than 16. + */ +static void cfl_luma_subsampling_420_lbd_avx2(const uint8_t *input, + int input_stride, + uint16_t *pred_buf_q3, int width, + int height) { + (void)width; // Forever 32 + const __m256i twos = _mm256_set1_epi8(2); // Thirty two twos + const int luma_stride = input_stride << 1; + __m256i *row = (__m256i *)pred_buf_q3; + const __m256i *row_end = row + (height >> 1) * CFL_BUF_LINE_I256; + do { + __m256i top = _mm256_loadu_si256((__m256i *)input); + __m256i bot = _mm256_loadu_si256((__m256i *)(input + input_stride)); + + __m256i top_16x16 = _mm256_maddubs_epi16(top, twos); + __m256i bot_16x16 = _mm256_maddubs_epi16(bot, twos); + __m256i sum_16x16 = _mm256_add_epi16(top_16x16, bot_16x16); + + _mm256_storeu_si256(row, sum_16x16); + + input += luma_stride; + } while ((row += CFL_BUF_LINE_I256) < row_end); +} + +CFL_GET_SUBSAMPLE_FUNCTION_AVX2(420, lbd) + +/** + * Adds 2 pixels (in a 2x1 grid) and multiplies them by 4. Resulting in a more + * precise version of a box filter 4:2:2 pixel subsampling in Q3. + * + * The CfL prediction buffer is always of size CFL_BUF_SQUARE. However, the + * active area is specified using width and height. + * + * Note: We don't need to worry about going over the active area, as long as we + * stay inside the CfL prediction buffer. + */ +static void cfl_luma_subsampling_422_lbd_avx2(const uint8_t *input, + int input_stride, + uint16_t *pred_buf_q3, int width, + int height) { + (void)width; // Forever 32 + const __m256i fours = _mm256_set1_epi8(4); // Thirty two fours + __m256i *row = (__m256i *)pred_buf_q3; + const __m256i *row_end = row + height * CFL_BUF_LINE_I256; + do { + __m256i top = _mm256_loadu_si256((__m256i *)input); + __m256i top_16x16 = _mm256_maddubs_epi16(top, fours); + _mm256_storeu_si256(row, top_16x16); + input += input_stride; + } while ((row += CFL_BUF_LINE_I256) < row_end); +} + +CFL_GET_SUBSAMPLE_FUNCTION_AVX2(422, lbd) + +/** + * Multiplies the pixels by 8 (scaling in Q3). The AVX2 subsampling is only + * performed on block of width 32. + * + * The CfL prediction buffer is always of size CFL_BUF_SQUARE. However, the + * active area is specified using width and height. + * + * Note: We don't need to worry about going over the active area, as long as we + * stay inside the CfL prediction buffer. + */ +static void cfl_luma_subsampling_444_lbd_avx2(const uint8_t *input, + int input_stride, + uint16_t *pred_buf_q3, int width, + int height) { + (void)width; // Forever 32 + __m256i *row = (__m256i *)pred_buf_q3; + const __m256i *row_end = row + height * CFL_BUF_LINE_I256; + const __m256i zeros = _mm256_setzero_si256(); + do { + __m256i top = _mm256_loadu_si256((__m256i *)input); + top = _mm256_permute4x64_epi64(top, _MM_SHUFFLE(3, 1, 2, 0)); + + __m256i row_lo = _mm256_unpacklo_epi8(top, zeros); + row_lo = _mm256_slli_epi16(row_lo, 3); + __m256i row_hi = _mm256_unpackhi_epi8(top, zeros); + row_hi = _mm256_slli_epi16(row_hi, 3); + + _mm256_storeu_si256(row, row_lo); + _mm256_storeu_si256(row + 1, row_hi); + + input += input_stride; + } while ((row += CFL_BUF_LINE_I256) < row_end); +} + +CFL_GET_SUBSAMPLE_FUNCTION_AVX2(444, lbd) + +/** + * Adds 4 pixels (in a 2x2 grid) and multiplies them by 2. Resulting in a more + * precise version of a box filter 4:2:0 pixel subsampling in Q3. + * + * The CfL prediction buffer is always of size CFL_BUF_SQUARE. However, the + * active area is specified using width and height. + * + * Note: We don't need to worry about going over the active area, as long as we + * stay inside the CfL prediction buffer. + * + * Note: For 4:2:0 luma subsampling, the width will never be greater than 16. + */ +static void cfl_luma_subsampling_420_hbd_avx2(const uint16_t *input, + int input_stride, + uint16_t *pred_buf_q3, int width, + int height) { + (void)width; // Forever 32 + const int luma_stride = input_stride << 1; + __m256i *row = (__m256i *)pred_buf_q3; + const __m256i *row_end = row + (height >> 1) * CFL_BUF_LINE_I256; + do { + __m256i top = _mm256_loadu_si256((__m256i *)input); + __m256i bot = _mm256_loadu_si256((__m256i *)(input + input_stride)); + __m256i sum = _mm256_add_epi16(top, bot); + + __m256i top_1 = _mm256_loadu_si256((__m256i *)(input + 16)); + __m256i bot_1 = _mm256_loadu_si256((__m256i *)(input + 16 + input_stride)); + __m256i sum_1 = _mm256_add_epi16(top_1, bot_1); + + __m256i hsum = _mm256_hadd_epi16(sum, sum_1); + hsum = _mm256_permute4x64_epi64(hsum, _MM_SHUFFLE(3, 1, 2, 0)); + hsum = _mm256_add_epi16(hsum, hsum); + + _mm256_storeu_si256(row, hsum); + + input += luma_stride; + } while ((row += CFL_BUF_LINE_I256) < row_end); +} + +CFL_GET_SUBSAMPLE_FUNCTION_AVX2(420, hbd) + +/** + * Adds 2 pixels (in a 2x1 grid) and multiplies them by 4. Resulting in a more + * precise version of a box filter 4:2:2 pixel subsampling in Q3. + * + * The CfL prediction buffer is always of size CFL_BUF_SQUARE. However, the + * active area is specified using width and height. + * + * Note: We don't need to worry about going over the active area, as long as we + * stay inside the CfL prediction buffer. + * + */ +static void cfl_luma_subsampling_422_hbd_avx2(const uint16_t *input, + int input_stride, + uint16_t *pred_buf_q3, int width, + int height) { + (void)width; // Forever 32 + __m256i *row = (__m256i *)pred_buf_q3; + const __m256i *row_end = row + height * CFL_BUF_LINE_I256; + do { + __m256i top = _mm256_loadu_si256((__m256i *)input); + __m256i top_1 = _mm256_loadu_si256((__m256i *)(input + 16)); + __m256i hsum = _mm256_hadd_epi16(top, top_1); + hsum = _mm256_permute4x64_epi64(hsum, _MM_SHUFFLE(3, 1, 2, 0)); + hsum = _mm256_slli_epi16(hsum, 2); + + _mm256_storeu_si256(row, hsum); + + input += input_stride; + } while ((row += CFL_BUF_LINE_I256) < row_end); +} + +CFL_GET_SUBSAMPLE_FUNCTION_AVX2(422, hbd) + +static void cfl_luma_subsampling_444_hbd_avx2(const uint16_t *input, + int input_stride, + uint16_t *pred_buf_q3, int width, + int height) { + (void)width; // Forever 32 + __m256i *row = (__m256i *)pred_buf_q3; + const __m256i *row_end = row + height * CFL_BUF_LINE_I256; + do { + __m256i top = _mm256_loadu_si256((__m256i *)input); + __m256i top_1 = _mm256_loadu_si256((__m256i *)(input + 16)); + _mm256_storeu_si256(row, _mm256_slli_epi16(top, 3)); + _mm256_storeu_si256(row + 1, _mm256_slli_epi16(top_1, 3)); + input += input_stride; + } while ((row += CFL_BUF_LINE_I256) < row_end); +} + +CFL_GET_SUBSAMPLE_FUNCTION_AVX2(444, hbd) + +static INLINE __m256i predict_unclipped(const __m256i *input, __m256i alpha_q12, + __m256i alpha_sign, __m256i dc_q0) { + __m256i ac_q3 = _mm256_loadu_si256(input); + __m256i ac_sign = _mm256_sign_epi16(alpha_sign, ac_q3); + __m256i scaled_luma_q0 = + _mm256_mulhrs_epi16(_mm256_abs_epi16(ac_q3), alpha_q12); + scaled_luma_q0 = _mm256_sign_epi16(scaled_luma_q0, ac_sign); + return _mm256_add_epi16(scaled_luma_q0, dc_q0); +} + +static INLINE void cfl_predict_lbd_avx2(const int16_t *pred_buf_q3, + uint8_t *dst, int dst_stride, + int alpha_q3, int width, int height) { + (void)width; + const __m256i alpha_sign = _mm256_set1_epi16(alpha_q3); + const __m256i alpha_q12 = _mm256_slli_epi16(_mm256_abs_epi16(alpha_sign), 9); + const __m256i dc_q0 = _mm256_set1_epi16(*dst); + __m256i *row = (__m256i *)pred_buf_q3; + const __m256i *row_end = row + height * CFL_BUF_LINE_I256; + + do { + __m256i res = predict_unclipped(row, alpha_q12, alpha_sign, dc_q0); + __m256i next = predict_unclipped(row + 1, alpha_q12, alpha_sign, dc_q0); + res = _mm256_packus_epi16(res, next); + res = _mm256_permute4x64_epi64(res, _MM_SHUFFLE(3, 1, 2, 0)); + _mm256_storeu_si256((__m256i *)dst, res); + dst += dst_stride; + } while ((row += CFL_BUF_LINE_I256) < row_end); +} + +CFL_PREDICT_X(avx2, 32, 8, lbd); +CFL_PREDICT_X(avx2, 32, 16, lbd); +CFL_PREDICT_X(avx2, 32, 32, lbd); + +cfl_predict_lbd_fn get_predict_lbd_fn_avx2(TX_SIZE tx_size) { + static const cfl_predict_lbd_fn pred[TX_SIZES_ALL] = { + predict_lbd_4x4_ssse3, /* 4x4 */ + predict_lbd_8x8_ssse3, /* 8x8 */ + predict_lbd_16x16_ssse3, /* 16x16 */ + predict_lbd_32x32_avx2, /* 32x32 */ + cfl_predict_lbd_null, /* 64x64 (invalid CFL size) */ + predict_lbd_4x8_ssse3, /* 4x8 */ + predict_lbd_8x4_ssse3, /* 8x4 */ + predict_lbd_8x16_ssse3, /* 8x16 */ + predict_lbd_16x8_ssse3, /* 16x8 */ + predict_lbd_16x32_ssse3, /* 16x32 */ + predict_lbd_32x16_avx2, /* 32x16 */ + cfl_predict_lbd_null, /* 32x64 (invalid CFL size) */ + cfl_predict_lbd_null, /* 64x32 (invalid CFL size) */ + predict_lbd_4x16_ssse3, /* 4x16 */ + predict_lbd_16x4_ssse3, /* 16x4 */ + predict_lbd_8x32_ssse3, /* 8x32 */ + predict_lbd_32x8_avx2, /* 32x8 */ + cfl_predict_lbd_null, /* 16x64 (invalid CFL size) */ + cfl_predict_lbd_null, /* 64x16 (invalid CFL size) */ + }; + // Modulo TX_SIZES_ALL to ensure that an attacker won't be able to index the + // function pointer array out of bounds. + return pred[tx_size % TX_SIZES_ALL]; +} + +static __m256i highbd_max_epi16(int bd) { + const __m256i neg_one = _mm256_set1_epi16(-1); + // (1 << bd) - 1 => -(-1 << bd) -1 => -1 - (-1 << bd) => -1 ^ (-1 << bd) + return _mm256_xor_si256(_mm256_slli_epi16(neg_one, bd), neg_one); +} + +static __m256i highbd_clamp_epi16(__m256i u, __m256i zero, __m256i max) { + return _mm256_max_epi16(_mm256_min_epi16(u, max), zero); +} + +static INLINE void cfl_predict_hbd_avx2(const int16_t *pred_buf_q3, + uint16_t *dst, int dst_stride, + int alpha_q3, int bd, int width, + int height) { + // Use SSSE3 version for smaller widths + assert(width == 16 || width == 32); + const __m256i alpha_sign = _mm256_set1_epi16(alpha_q3); + const __m256i alpha_q12 = _mm256_slli_epi16(_mm256_abs_epi16(alpha_sign), 9); + const __m256i dc_q0 = _mm256_loadu_si256((__m256i *)dst); + const __m256i max = highbd_max_epi16(bd); + + __m256i *row = (__m256i *)pred_buf_q3; + const __m256i *row_end = row + height * CFL_BUF_LINE_I256; + do { + const __m256i res = predict_unclipped(row, alpha_q12, alpha_sign, dc_q0); + _mm256_storeu_si256((__m256i *)dst, + highbd_clamp_epi16(res, _mm256_setzero_si256(), max)); + if (width == 32) { + const __m256i res_1 = + predict_unclipped(row + 1, alpha_q12, alpha_sign, dc_q0); + _mm256_storeu_si256( + (__m256i *)(dst + 16), + highbd_clamp_epi16(res_1, _mm256_setzero_si256(), max)); + } + dst += dst_stride; + } while ((row += CFL_BUF_LINE_I256) < row_end); +} + +CFL_PREDICT_X(avx2, 16, 4, hbd) +CFL_PREDICT_X(avx2, 16, 8, hbd) +CFL_PREDICT_X(avx2, 16, 16, hbd) +CFL_PREDICT_X(avx2, 16, 32, hbd) +CFL_PREDICT_X(avx2, 32, 8, hbd) +CFL_PREDICT_X(avx2, 32, 16, hbd) +CFL_PREDICT_X(avx2, 32, 32, hbd) + +cfl_predict_hbd_fn get_predict_hbd_fn_avx2(TX_SIZE tx_size) { + static const cfl_predict_hbd_fn pred[TX_SIZES_ALL] = { + predict_hbd_4x4_ssse3, /* 4x4 */ + predict_hbd_8x8_ssse3, /* 8x8 */ + predict_hbd_16x16_avx2, /* 16x16 */ + predict_hbd_32x32_avx2, /* 32x32 */ + cfl_predict_hbd_null, /* 64x64 (invalid CFL size) */ + predict_hbd_4x8_ssse3, /* 4x8 */ + predict_hbd_8x4_ssse3, /* 8x4 */ + predict_hbd_8x16_ssse3, /* 8x16 */ + predict_hbd_16x8_avx2, /* 16x8 */ + predict_hbd_16x32_avx2, /* 16x32 */ + predict_hbd_32x16_avx2, /* 32x16 */ + cfl_predict_hbd_null, /* 32x64 (invalid CFL size) */ + cfl_predict_hbd_null, /* 64x32 (invalid CFL size) */ + predict_hbd_4x16_ssse3, /* 4x16 */ + predict_hbd_16x4_avx2, /* 16x4 */ + predict_hbd_8x32_ssse3, /* 8x32 */ + predict_hbd_32x8_avx2, /* 32x8 */ + cfl_predict_hbd_null, /* 16x64 (invalid CFL size) */ + cfl_predict_hbd_null, /* 64x16 (invalid CFL size) */ + }; + // Modulo TX_SIZES_ALL to ensure that an attacker won't be able to index the + // function pointer array out of bounds. + return pred[tx_size % TX_SIZES_ALL]; +} + +// Returns a vector where all the (32-bits) elements are the sum of all the +// lanes in a. +static INLINE __m256i fill_sum_epi32(__m256i a) { + // Given that a == [A, B, C, D, E, F, G, H] + a = _mm256_hadd_epi32(a, a); + // Given that A' == A + B, C' == C + D, E' == E + F, G' == G + H + // a == [A', C', A', C', E', G', E', G'] + a = _mm256_permute4x64_epi64(a, _MM_SHUFFLE(3, 1, 2, 0)); + // a == [A', C', E', G', A', C', E', G'] + a = _mm256_hadd_epi32(a, a); + // Given that A'' == A' + C' and E'' == E' + G' + // a == [A'', E'', A'', E'', A'', E'', A'', E''] + return _mm256_hadd_epi32(a, a); + // Given that A''' == A'' + E'' + // a == [A''', A''', A''', A''', A''', A''', A''', A'''] +} + +static INLINE __m256i _mm256_addl_epi16(__m256i a) { + return _mm256_add_epi32(_mm256_unpacklo_epi16(a, _mm256_setzero_si256()), + _mm256_unpackhi_epi16(a, _mm256_setzero_si256())); +} + +static INLINE void subtract_average_avx2(const uint16_t *src_ptr, + int16_t *dst_ptr, int width, + int height, int round_offset, + int num_pel_log2) { + // Use SSE2 version for smaller widths + assert(width == 16 || width == 32); + + const __m256i *src = (__m256i *)src_ptr; + const __m256i *const end = src + height * CFL_BUF_LINE_I256; + // To maximize usage of the AVX2 registers, we sum two rows per loop + // iteration + const int step = 2 * CFL_BUF_LINE_I256; + + __m256i sum = _mm256_setzero_si256(); + // For width 32, we use a second sum accumulator to reduce accumulator + // dependencies in the loop. + __m256i sum2; + if (width == 32) sum2 = _mm256_setzero_si256(); + + do { + // Add top row to the bottom row + __m256i l0 = _mm256_add_epi16(_mm256_loadu_si256(src), + _mm256_loadu_si256(src + CFL_BUF_LINE_I256)); + sum = _mm256_add_epi32(sum, _mm256_addl_epi16(l0)); + if (width == 32) { /* Don't worry, this if it gets optimized out. */ + // Add the second part of the top row to the second part of the bottom row + __m256i l1 = + _mm256_add_epi16(_mm256_loadu_si256(src + 1), + _mm256_loadu_si256(src + 1 + CFL_BUF_LINE_I256)); + sum2 = _mm256_add_epi32(sum2, _mm256_addl_epi16(l1)); + } + src += step; + } while (src < end); + // Combine both sum accumulators + if (width == 32) sum = _mm256_add_epi32(sum, sum2); + + __m256i fill = fill_sum_epi32(sum); + + __m256i avg_epi16 = _mm256_srli_epi32( + _mm256_add_epi32(fill, _mm256_set1_epi32(round_offset)), num_pel_log2); + avg_epi16 = _mm256_packs_epi32(avg_epi16, avg_epi16); + + // Store and subtract loop + src = (__m256i *)src_ptr; + __m256i *dst = (__m256i *)dst_ptr; + do { + _mm256_storeu_si256(dst, + _mm256_sub_epi16(_mm256_loadu_si256(src), avg_epi16)); + if (width == 32) { + _mm256_storeu_si256( + dst + 1, _mm256_sub_epi16(_mm256_loadu_si256(src + 1), avg_epi16)); + } + src += CFL_BUF_LINE_I256; + dst += CFL_BUF_LINE_I256; + } while (src < end); +} + +// Declare wrappers for AVX2 sizes +CFL_SUB_AVG_X(avx2, 16, 4, 32, 6) +CFL_SUB_AVG_X(avx2, 16, 8, 64, 7) +CFL_SUB_AVG_X(avx2, 16, 16, 128, 8) +CFL_SUB_AVG_X(avx2, 16, 32, 256, 9) +CFL_SUB_AVG_X(avx2, 32, 8, 128, 8) +CFL_SUB_AVG_X(avx2, 32, 16, 256, 9) +CFL_SUB_AVG_X(avx2, 32, 32, 512, 10) + +// Based on the observation that for small blocks AVX2 does not outperform +// SSE2, we call the SSE2 code for block widths 4 and 8. +cfl_subtract_average_fn get_subtract_average_fn_avx2(TX_SIZE tx_size) { + static const cfl_subtract_average_fn sub_avg[TX_SIZES_ALL] = { + subtract_average_4x4_sse2, /* 4x4 */ + subtract_average_8x8_sse2, /* 8x8 */ + subtract_average_16x16_avx2, /* 16x16 */ + subtract_average_32x32_avx2, /* 32x32 */ + cfl_subtract_average_null, /* 64x64 (invalid CFL size) */ + subtract_average_4x8_sse2, /* 4x8 */ + subtract_average_8x4_sse2, /* 8x4 */ + subtract_average_8x16_sse2, /* 8x16 */ + subtract_average_16x8_avx2, /* 16x8 */ + subtract_average_16x32_avx2, /* 16x32 */ + subtract_average_32x16_avx2, /* 32x16 */ + cfl_subtract_average_null, /* 32x64 (invalid CFL size) */ + cfl_subtract_average_null, /* 64x32 (invalid CFL size) */ + subtract_average_4x16_sse2, /* 4x16 */ + subtract_average_16x4_avx2, /* 16x4 */ + subtract_average_8x32_sse2, /* 8x32 */ + subtract_average_32x8_avx2, /* 32x8 */ + cfl_subtract_average_null, /* 16x64 (invalid CFL size) */ + cfl_subtract_average_null, /* 64x16 (invalid CFL size) */ + }; + // Modulo TX_SIZES_ALL to ensure that an attacker won't be able to + // index the function pointer array out of bounds. + return sub_avg[tx_size % TX_SIZES_ALL]; +} |