Refactor Neon implementations of variance functions Factor out common code into width-specific helper functions of the form variance_<w>xh_neon. An alternative (faster) Armv8.4-A dot- product implementation of each helper function will be added in a subsequent patch. Change-Id: Ib81ed5d9903de98c932b08b5628897e5f79eeb5f
diff --git a/aom_dsp/arm/mem_neon.h b/aom_dsp/arm/mem_neon.h index 9f79ec5..e7872d9 100644 --- a/aom_dsp/arm/mem_neon.h +++ b/aom_dsp/arm/mem_neon.h
@@ -316,6 +316,17 @@ *s3 = vld1q_s16(s); } +// Load 2 sets of 4 bytes when alignment is not guaranteed. +static INLINE uint8x8_t load_unaligned_u8(const uint8_t *buf, int stride) { + uint32_t a; + memcpy(&a, buf, 4); + buf += stride; + uint32x2_t a_u32 = vdup_n_u32(a); + memcpy(&a, buf, 4); + a_u32 = vset_lane_u32(a, a_u32, 1); + return vreinterpret_u8_u32(a_u32); +} + // Load 4 sets of 4 bytes when alignment is not guaranteed. static INLINE uint8x16_t load_unaligned_u8q(const uint8_t *buf, int stride) { uint32_t a;
diff --git a/aom_dsp/arm/variance_neon.c b/aom_dsp/arm/variance_neon.c index 3378491..1b6c43a 100644 --- a/aom_dsp/arm/variance_neon.c +++ b/aom_dsp/arm/variance_neon.c
@@ -13,291 +13,243 @@ #include "config/aom_dsp_rtcd.h" #include "config/aom_config.h" +#include "aom_dsp/arm/mem_neon.h" #include "aom_dsp/arm/sum_neon.h" #include "aom/aom_integer.h" #include "aom_ports/mem.h" -// w * h must be less than 2048 or local variable v_sum may overflow. -static void variance_neon_w8(const uint8_t *a, int a_stride, const uint8_t *b, - int b_stride, int w, int h, uint32_t *sse, - int *sum) { - int i, j; - int16x8_t v_sum = vdupq_n_s16(0); - int32x4_t v_sse_lo = vdupq_n_s32(0); - int32x4_t v_sse_hi = vdupq_n_s32(0); +static INLINE void variance_4xh_neon(const uint8_t *src, int src_stride, + const uint8_t *ref, int ref_stride, int h, + uint32_t *sse, int *sum) { + int16x8_t sum_s16 = vdupq_n_s16(0); + int32x4_t sse_s32 = vdupq_n_s32(0); - for (i = 0; i < h; ++i) { - for (j = 0; j < w; j += 8) { - const uint8x8_t v_a = vld1_u8(&a[j]); - const uint8x8_t v_b = vld1_u8(&b[j]); - const uint16x8_t v_diff = vsubl_u8(v_a, v_b); - const int16x8_t sv_diff = vreinterpretq_s16_u16(v_diff); - v_sum = vaddq_s16(v_sum, sv_diff); - v_sse_lo = - vmlal_s16(v_sse_lo, vget_low_s16(sv_diff), vget_low_s16(sv_diff)); - v_sse_hi = - vmlal_s16(v_sse_hi, vget_high_s16(sv_diff), vget_high_s16(sv_diff)); - } - a += a_stride; - b += b_stride; + // Number of rows we can process before 'sum_s16' overflows: + // 32767 / 255 ~= 128, but we use an 8-wide accumulator; so 256 4-wide rows. + assert(h <= 256); + + int i = 0; + do { + uint8x8_t s = load_unaligned_u8(src, src_stride); + uint8x8_t r = load_unaligned_u8(ref, ref_stride); + int16x8_t diff = vreinterpretq_s16_u16(vsubl_u8(s, r)); + + sum_s16 = vaddq_s16(sum_s16, diff); + + sse_s32 = vmlal_s16(sse_s32, vget_low_s16(diff), vget_low_s16(diff)); + sse_s32 = vmlal_s16(sse_s32, vget_high_s16(diff), vget_high_s16(diff)); + + src += 2 * src_stride; + ref += 2 * ref_stride; + i += 2; + } while (i < h); + + *sum = horizontal_add_s16x8(sum_s16); + *sse = (uint32_t)horizontal_add_s32x4(sse_s32); +} + +static INLINE void variance_8xh_neon(const uint8_t *src, int src_stride, + const uint8_t *ref, int ref_stride, int h, + uint32_t *sse, int *sum) { + int16x8_t sum_s16 = vdupq_n_s16(0); + int32x4_t sse_s32[2] = { vdupq_n_s32(0), vdupq_n_s32(0) }; + + // Number of rows we can process before 'sum_s16' overflows: + // 32767 / 255 ~= 128 + assert(h <= 128); + + int i = 0; + do { + uint8x8_t s = vld1_u8(src); + uint8x8_t r = vld1_u8(ref); + int16x8_t diff = vreinterpretq_s16_u16(vsubl_u8(s, r)); + + sum_s16 = vaddq_s16(sum_s16, diff); + + sse_s32[0] = vmlal_s16(sse_s32[0], vget_low_s16(diff), vget_low_s16(diff)); + sse_s32[1] = + vmlal_s16(sse_s32[1], vget_high_s16(diff), vget_high_s16(diff)); + + src += src_stride; + ref += ref_stride; + i++; + } while (i < h); + + *sum = horizontal_add_s16x8(sum_s16); + *sse = (uint32_t)horizontal_add_s32x4(vaddq_s32(sse_s32[0], sse_s32[1])); +} + +static INLINE void variance_16xh_neon(const uint8_t *src, int src_stride, + const uint8_t *ref, int ref_stride, int h, + uint32_t *sse, int *sum) { + int16x8_t sum_s16[2] = { vdupq_n_s16(0), vdupq_n_s16(0) }; + int32x4_t sse_s32[2] = { vdupq_n_s32(0), vdupq_n_s32(0) }; + + // Number of rows we can process before 'sum_s16' accumulators overflow: + // 32767 / 255 ~= 128, so 128 16-wide rows. + assert(h <= 128); + + int i = 0; + do { + uint8x16_t s = vld1q_u8(src); + uint8x16_t r = vld1q_u8(ref); + + int16x8_t diff_l = + vreinterpretq_s16_u16(vsubl_u8(vget_low_u8(s), vget_low_u8(r))); + int16x8_t diff_h = + vreinterpretq_s16_u16(vsubl_u8(vget_high_u8(s), vget_high_u8(r))); + + sum_s16[0] = vaddq_s16(sum_s16[0], diff_l); + sum_s16[1] = vaddq_s16(sum_s16[1], diff_h); + + sse_s32[0] = + vmlal_s16(sse_s32[0], vget_low_s16(diff_l), vget_low_s16(diff_l)); + sse_s32[1] = + vmlal_s16(sse_s32[1], vget_high_s16(diff_l), vget_high_s16(diff_l)); + sse_s32[0] = + vmlal_s16(sse_s32[0], vget_low_s16(diff_h), vget_low_s16(diff_h)); + sse_s32[1] = + vmlal_s16(sse_s32[1], vget_high_s16(diff_h), vget_high_s16(diff_h)); + + src += src_stride; + ref += ref_stride; + i++; + } while (i < h); + + *sum = horizontal_add_s16x8(vaddq_s16(sum_s16[0], sum_s16[1])); + *sse = (uint32_t)horizontal_add_s32x4(vaddq_s32(sse_s32[0], sse_s32[1])); +} + +static INLINE void variance_large_neon(const uint8_t *src, int src_stride, + const uint8_t *ref, int ref_stride, + int w, int h, int h_limit, uint32_t *sse, + int *sum) { + int32x4_t sum_s32 = vdupq_n_s32(0); + int32x4_t sse_s32[2] = { vdupq_n_s32(0), vdupq_n_s32(0) }; + + // 'h_limit' is the number of 'w'-width rows we can process before our 16-bit + // accumulator overflows. After hitting this limit we accumulate into 32-bit + // elements. + int h_tmp = h > h_limit ? h_limit : h; + + int i = 0; + do { + int16x8_t sum_s16[2] = { vdupq_n_s16(0), vdupq_n_s16(0) }; + do { + int j = 0; + do { + uint8x16_t s = vld1q_u8(src + j); + uint8x16_t r = vld1q_u8(ref + j); + + int16x8_t diff_l = + vreinterpretq_s16_u16(vsubl_u8(vget_low_u8(s), vget_low_u8(r))); + int16x8_t diff_h = + vreinterpretq_s16_u16(vsubl_u8(vget_high_u8(s), vget_high_u8(r))); + + sum_s16[0] = vaddq_s16(sum_s16[0], diff_l); + sum_s16[1] = vaddq_s16(sum_s16[1], diff_h); + + sse_s32[0] = + vmlal_s16(sse_s32[0], vget_low_s16(diff_l), vget_low_s16(diff_l)); + sse_s32[1] = + vmlal_s16(sse_s32[1], vget_high_s16(diff_l), vget_high_s16(diff_l)); + sse_s32[0] = + vmlal_s16(sse_s32[0], vget_low_s16(diff_h), vget_low_s16(diff_h)); + sse_s32[1] = + vmlal_s16(sse_s32[1], vget_high_s16(diff_h), vget_high_s16(diff_h)); + + j += 16; + } while (j < w); + + src += src_stride; + ref += ref_stride; + i++; + } while (i < h_tmp); + + sum_s32 = vpadalq_s16(sum_s32, sum_s16[0]); + sum_s32 = vpadalq_s16(sum_s32, sum_s16[1]); + + h_tmp += h_limit; + } while (i < h); + + *sum = horizontal_add_s32x4(sum_s32); + *sse = (uint32_t)horizontal_add_s32x4(vaddq_s32(sse_s32[0], sse_s32[1])); +} + +static INLINE void variance_32xh_neon(const uint8_t *src, int src_stride, + const uint8_t *ref, int ref_stride, int h, + uint32_t *sse, int *sum) { + variance_large_neon(src, src_stride, ref, ref_stride, 32, h, 64, sse, sum); +} + +static INLINE void variance_64xh_neon(const uint8_t *src, int src_stride, + const uint8_t *ref, int ref_stride, int h, + uint32_t *sse, int *sum) { + variance_large_neon(src, src_stride, ref, ref_stride, 64, h, 32, sse, sum); +} + +static INLINE void variance_128xh_neon(const uint8_t *src, int src_stride, + const uint8_t *ref, int ref_stride, + int h, uint32_t *sse, int *sum) { + variance_large_neon(src, src_stride, ref, ref_stride, 128, h, 16, sse, sum); +} + +#define VARIANCE_WXH_NEON(w, h, shift) \ + unsigned int aom_variance##w##x##h##_neon( \ + const uint8_t *src, int src_stride, const uint8_t *ref, int ref_stride, \ + unsigned int *sse) { \ + int sum; \ + variance_##w##xh_neon(src, src_stride, ref, ref_stride, h, sse, &sum); \ + return *sse - (uint32_t)(((int64_t)sum * sum) >> shift); \ } - *sum = horizontal_add_s16x8(v_sum); - *sse = (unsigned int)horizontal_add_s32x4(vaddq_s32(v_sse_lo, v_sse_hi)); +VARIANCE_WXH_NEON(4, 4, 4) +VARIANCE_WXH_NEON(4, 8, 5) + +VARIANCE_WXH_NEON(8, 4, 5) +VARIANCE_WXH_NEON(8, 8, 6) +VARIANCE_WXH_NEON(8, 16, 7) + +VARIANCE_WXH_NEON(16, 8, 7) +VARIANCE_WXH_NEON(16, 16, 8) +VARIANCE_WXH_NEON(16, 32, 9) + +VARIANCE_WXH_NEON(32, 16, 9) +VARIANCE_WXH_NEON(32, 32, 10) +VARIANCE_WXH_NEON(32, 64, 11) + +VARIANCE_WXH_NEON(64, 32, 11) +VARIANCE_WXH_NEON(64, 64, 12) +VARIANCE_WXH_NEON(64, 128, 13) + +VARIANCE_WXH_NEON(128, 64, 13) +VARIANCE_WXH_NEON(128, 128, 14) + +#undef VARIANCE_WXH_NEON + +void aom_get8x8var_neon(const uint8_t *src, int src_stride, const uint8_t *ref, + int ref_stride, unsigned int *sse, int *sum) { + variance_8xh_neon(src, src_stride, ref, ref_stride, 8, sse, sum); } -void aom_get8x8var_neon(const uint8_t *a, int a_stride, const uint8_t *b, - int b_stride, unsigned int *sse, int *sum) { - variance_neon_w8(a, a_stride, b, b_stride, 8, 8, sse, sum); -} - -void aom_get16x16var_neon(const uint8_t *a, int a_stride, const uint8_t *b, - int b_stride, unsigned int *sse, int *sum) { - variance_neon_w8(a, a_stride, b, b_stride, 16, 16, sse, sum); +void aom_get16x16var_neon(const uint8_t *src, int src_stride, + const uint8_t *ref, int ref_stride, unsigned int *sse, + int *sum) { + variance_16xh_neon(src, src_stride, ref, ref_stride, 16, sse, sum); } // TODO(yunqingwang): Perform variance of two/four 8x8 blocks similar to that of // AVX2. -void aom_get_sse_sum_8x8_quad_neon(const uint8_t *a, int a_stride, - const uint8_t *b, int b_stride, +void aom_get_sse_sum_8x8_quad_neon(const uint8_t *src, int src_stride, + const uint8_t *ref, int ref_stride, unsigned int *sse, int *sum) { // Loop over 4 8x8 blocks. Process one 8x32 block. for (int k = 0; k < 4; k++) { - variance_neon_w8(a + (k * 8), a_stride, b + (k * 8), b_stride, 8, 8, - &sse[k], &sum[k]); + variance_8xh_neon(src + (k * 8), src_stride, ref + (k * 8), ref_stride, 8, + &sse[k], &sum[k]); } } -unsigned int aom_variance8x8_neon(const uint8_t *a, int a_stride, - const uint8_t *b, int b_stride, - unsigned int *sse) { - int sum; - variance_neon_w8(a, a_stride, b, b_stride, 8, 8, sse, &sum); - return *sse - ((sum * sum) >> 6); -} - -unsigned int aom_variance16x16_neon(const uint8_t *a, int a_stride, - const uint8_t *b, int b_stride, - unsigned int *sse) { - int sum; - variance_neon_w8(a, a_stride, b, b_stride, 16, 16, sse, &sum); - return *sse - (((unsigned int)((int64_t)sum * sum)) >> 8); -} - -unsigned int aom_variance32x32_neon(const uint8_t *a, int a_stride, - const uint8_t *b, int b_stride, - unsigned int *sse) { - int sum; - variance_neon_w8(a, a_stride, b, b_stride, 32, 32, sse, &sum); - return *sse - (unsigned int)(((int64_t)sum * sum) >> 10); -} - -unsigned int aom_variance32x64_neon(const uint8_t *a, int a_stride, - const uint8_t *b, int b_stride, - unsigned int *sse) { - int sum1, sum2; - uint32_t sse1, sse2; - variance_neon_w8(a, a_stride, b, b_stride, 32, 32, &sse1, &sum1); - variance_neon_w8(a + (32 * a_stride), a_stride, b + (32 * b_stride), b_stride, - 32, 32, &sse2, &sum2); - *sse = sse1 + sse2; - sum1 += sum2; - return *sse - (unsigned int)(((int64_t)sum1 * sum1) >> 11); -} - -unsigned int aom_variance64x32_neon(const uint8_t *a, int a_stride, - const uint8_t *b, int b_stride, - unsigned int *sse) { - int sum1, sum2; - uint32_t sse1, sse2; - variance_neon_w8(a, a_stride, b, b_stride, 64, 16, &sse1, &sum1); - variance_neon_w8(a + (16 * a_stride), a_stride, b + (16 * b_stride), b_stride, - 64, 16, &sse2, &sum2); - *sse = sse1 + sse2; - sum1 += sum2; - return *sse - (unsigned int)(((int64_t)sum1 * sum1) >> 11); -} - -unsigned int aom_variance64x64_neon(const uint8_t *a, int a_stride, - const uint8_t *b, int b_stride, - unsigned int *sse) { - int sum1, sum2; - uint32_t sse1, sse2; - - variance_neon_w8(a, a_stride, b, b_stride, 64, 16, &sse1, &sum1); - variance_neon_w8(a + (16 * a_stride), a_stride, b + (16 * b_stride), b_stride, - 64, 16, &sse2, &sum2); - sse1 += sse2; - sum1 += sum2; - - variance_neon_w8(a + (16 * 2 * a_stride), a_stride, b + (16 * 2 * b_stride), - b_stride, 64, 16, &sse2, &sum2); - sse1 += sse2; - sum1 += sum2; - - variance_neon_w8(a + (16 * 3 * a_stride), a_stride, b + (16 * 3 * b_stride), - b_stride, 64, 16, &sse2, &sum2); - *sse = sse1 + sse2; - sum1 += sum2; - return *sse - (unsigned int)(((int64_t)sum1 * sum1) >> 12); -} - -unsigned int aom_variance128x128_neon(const uint8_t *a, int a_stride, - const uint8_t *b, int b_stride, - unsigned int *sse) { - int sum1, sum2; - uint32_t sse1, sse2; - sum1 = sse1 = 0; - for (int i = 0; i < 16; i++) { - variance_neon_w8(a + (8 * i * a_stride), a_stride, b + (8 * i * b_stride), - b_stride, 128, 8, &sse2, &sum2); - sse1 += sse2; - sum1 += sum2; - } - - *sse = sse1; - - return *sse - (unsigned int)(((int64_t)sum1 * sum1) >> 14); -} - -unsigned int aom_variance16x8_neon(const unsigned char *src_ptr, - int source_stride, - const unsigned char *ref_ptr, - int recon_stride, unsigned int *sse) { - int i; - int16x4_t d22s16, d23s16, d24s16, d25s16, d26s16, d27s16, d28s16, d29s16; - uint32x2_t d0u32, d10u32; - int64x1_t d0s64, d1s64; - uint8x16_t q0u8, q1u8, q2u8, q3u8; - uint16x8_t q11u16, q12u16, q13u16, q14u16; - int32x4_t q8s32, q9s32, q10s32; - int64x2_t q0s64, q1s64, q5s64; - - q8s32 = vdupq_n_s32(0); - q9s32 = vdupq_n_s32(0); - q10s32 = vdupq_n_s32(0); - - for (i = 0; i < 4; i++) { - q0u8 = vld1q_u8(src_ptr); - src_ptr += source_stride; - q1u8 = vld1q_u8(src_ptr); - src_ptr += source_stride; - __builtin_prefetch(src_ptr); - - q2u8 = vld1q_u8(ref_ptr); - ref_ptr += recon_stride; - q3u8 = vld1q_u8(ref_ptr); - ref_ptr += recon_stride; - __builtin_prefetch(ref_ptr); - - q11u16 = vsubl_u8(vget_low_u8(q0u8), vget_low_u8(q2u8)); - q12u16 = vsubl_u8(vget_high_u8(q0u8), vget_high_u8(q2u8)); - q13u16 = vsubl_u8(vget_low_u8(q1u8), vget_low_u8(q3u8)); - q14u16 = vsubl_u8(vget_high_u8(q1u8), vget_high_u8(q3u8)); - - d22s16 = vreinterpret_s16_u16(vget_low_u16(q11u16)); - d23s16 = vreinterpret_s16_u16(vget_high_u16(q11u16)); - q8s32 = vpadalq_s16(q8s32, vreinterpretq_s16_u16(q11u16)); - q9s32 = vmlal_s16(q9s32, d22s16, d22s16); - q10s32 = vmlal_s16(q10s32, d23s16, d23s16); - - d24s16 = vreinterpret_s16_u16(vget_low_u16(q12u16)); - d25s16 = vreinterpret_s16_u16(vget_high_u16(q12u16)); - q8s32 = vpadalq_s16(q8s32, vreinterpretq_s16_u16(q12u16)); - q9s32 = vmlal_s16(q9s32, d24s16, d24s16); - q10s32 = vmlal_s16(q10s32, d25s16, d25s16); - - d26s16 = vreinterpret_s16_u16(vget_low_u16(q13u16)); - d27s16 = vreinterpret_s16_u16(vget_high_u16(q13u16)); - q8s32 = vpadalq_s16(q8s32, vreinterpretq_s16_u16(q13u16)); - q9s32 = vmlal_s16(q9s32, d26s16, d26s16); - q10s32 = vmlal_s16(q10s32, d27s16, d27s16); - - d28s16 = vreinterpret_s16_u16(vget_low_u16(q14u16)); - d29s16 = vreinterpret_s16_u16(vget_high_u16(q14u16)); - q8s32 = vpadalq_s16(q8s32, vreinterpretq_s16_u16(q14u16)); - q9s32 = vmlal_s16(q9s32, d28s16, d28s16); - q10s32 = vmlal_s16(q10s32, d29s16, d29s16); - } - - q10s32 = vaddq_s32(q10s32, q9s32); - q0s64 = vpaddlq_s32(q8s32); - q1s64 = vpaddlq_s32(q10s32); - - d0s64 = vadd_s64(vget_low_s64(q0s64), vget_high_s64(q0s64)); - d1s64 = vadd_s64(vget_low_s64(q1s64), vget_high_s64(q1s64)); - - q5s64 = vmull_s32(vreinterpret_s32_s64(d0s64), vreinterpret_s32_s64(d0s64)); - vst1_lane_u32((uint32_t *)sse, vreinterpret_u32_s64(d1s64), 0); - - d10u32 = vshr_n_u32(vreinterpret_u32_s64(vget_low_s64(q5s64)), 7); - d0u32 = vsub_u32(vreinterpret_u32_s64(d1s64), d10u32); - - return vget_lane_u32(d0u32, 0); -} - -unsigned int aom_variance8x16_neon(const unsigned char *src_ptr, - int source_stride, - const unsigned char *ref_ptr, - int recon_stride, unsigned int *sse) { - int i; - uint8x8_t d0u8, d2u8, d4u8, d6u8; - int16x4_t d22s16, d23s16, d24s16, d25s16; - uint32x2_t d0u32, d10u32; - int64x1_t d0s64, d1s64; - uint16x8_t q11u16, q12u16; - int32x4_t q8s32, q9s32, q10s32; - int64x2_t q0s64, q1s64, q5s64; - - q8s32 = vdupq_n_s32(0); - q9s32 = vdupq_n_s32(0); - q10s32 = vdupq_n_s32(0); - - for (i = 0; i < 8; i++) { - d0u8 = vld1_u8(src_ptr); - src_ptr += source_stride; - d2u8 = vld1_u8(src_ptr); - src_ptr += source_stride; - __builtin_prefetch(src_ptr); - - d4u8 = vld1_u8(ref_ptr); - ref_ptr += recon_stride; - d6u8 = vld1_u8(ref_ptr); - ref_ptr += recon_stride; - __builtin_prefetch(ref_ptr); - - q11u16 = vsubl_u8(d0u8, d4u8); - q12u16 = vsubl_u8(d2u8, d6u8); - - d22s16 = vreinterpret_s16_u16(vget_low_u16(q11u16)); - d23s16 = vreinterpret_s16_u16(vget_high_u16(q11u16)); - q8s32 = vpadalq_s16(q8s32, vreinterpretq_s16_u16(q11u16)); - q9s32 = vmlal_s16(q9s32, d22s16, d22s16); - q10s32 = vmlal_s16(q10s32, d23s16, d23s16); - - d24s16 = vreinterpret_s16_u16(vget_low_u16(q12u16)); - d25s16 = vreinterpret_s16_u16(vget_high_u16(q12u16)); - q8s32 = vpadalq_s16(q8s32, vreinterpretq_s16_u16(q12u16)); - q9s32 = vmlal_s16(q9s32, d24s16, d24s16); - q10s32 = vmlal_s16(q10s32, d25s16, d25s16); - } - - q10s32 = vaddq_s32(q10s32, q9s32); - q0s64 = vpaddlq_s32(q8s32); - q1s64 = vpaddlq_s32(q10s32); - - d0s64 = vadd_s64(vget_low_s64(q0s64), vget_high_s64(q0s64)); - d1s64 = vadd_s64(vget_low_s64(q1s64), vget_high_s64(q1s64)); - - q5s64 = vmull_s32(vreinterpret_s32_s64(d0s64), vreinterpret_s32_s64(d0s64)); - vst1_lane_u32((uint32_t *)sse, vreinterpret_u32_s64(d1s64), 0); - - d10u32 = vshr_n_u32(vreinterpret_u32_s64(vget_low_s64(q5s64)), 7); - d0u32 = vsub_u32(vreinterpret_u32_s64(d1s64), d10u32); - - return vget_lane_u32(d0u32, 0); -} - unsigned int aom_mse16x16_neon(const unsigned char *src_ptr, int source_stride, const unsigned char *ref_ptr, int recon_stride, unsigned int *sse) { @@ -411,241 +363,3 @@ return vget_lane_u32(vreinterpret_u32_s64(d0s64), 0); } - -// Load 4 sets of 4 bytes when alignment is not guaranteed. -static INLINE uint8x16_t load_unaligned_u8q(const uint8_t *buf, int stride) { - uint32_t a; - uint32x4_t a_u32 = vdupq_n_u32(0); - if (stride == 4) return vld1q_u8(buf); - memcpy(&a, buf, 4); - buf += stride; - a_u32 = vld1q_lane_u32(&a, a_u32, 0); - memcpy(&a, buf, 4); - buf += stride; - a_u32 = vld1q_lane_u32(&a, a_u32, 1); - memcpy(&a, buf, 4); - buf += stride; - a_u32 = vld1q_lane_u32(&a, a_u32, 2); - memcpy(&a, buf, 4); - buf += stride; - a_u32 = vld1q_lane_u32(&a, a_u32, 3); - return vreinterpretq_u8_u32(a_u32); -} - -// The variance helper functions use int16_t for sum. 8 values are accumulated -// and then added (at which point they expand up to int32_t). To avoid overflow, -// there can be no more than 32767 / 255 ~= 128 values accumulated in each -// column. For a 32x32 buffer, this results in 32 / 8 = 4 values per row * 32 -// rows = 128. Asserts have been added to each function to warn against reaching -// this limit. - -// Process a block of width 4 four rows at a time. -static void variance_neon_w4x4(const uint8_t *a, int a_stride, const uint8_t *b, - int b_stride, int h, uint32_t *sse, int *sum) { - const int32x4_t zero = vdupq_n_s32(0); - int16x8_t sum_s16 = vreinterpretq_s16_s32(zero); - int32x4_t sse_s32 = zero; - - // Since width is only 4, sum_s16 only loads a half row per loop. - assert(h <= 256); - - int i; - for (i = 0; i < h; i += 4) { - const uint8x16_t a_u8 = load_unaligned_u8q(a, a_stride); - const uint8x16_t b_u8 = load_unaligned_u8q(b, b_stride); - const int16x8_t diff_lo_s16 = - vreinterpretq_s16_u16(vsubl_u8(vget_low_u8(a_u8), vget_low_u8(b_u8))); - const int16x8_t diff_hi_s16 = - vreinterpretq_s16_u16(vsubl_u8(vget_high_u8(a_u8), vget_high_u8(b_u8))); - - sum_s16 = vaddq_s16(sum_s16, diff_lo_s16); - sum_s16 = vaddq_s16(sum_s16, diff_hi_s16); - - sse_s32 = vmlal_s16(sse_s32, vget_low_s16(diff_lo_s16), - vget_low_s16(diff_lo_s16)); - sse_s32 = vmlal_s16(sse_s32, vget_high_s16(diff_lo_s16), - vget_high_s16(diff_lo_s16)); - - sse_s32 = vmlal_s16(sse_s32, vget_low_s16(diff_hi_s16), - vget_low_s16(diff_hi_s16)); - sse_s32 = vmlal_s16(sse_s32, vget_high_s16(diff_hi_s16), - vget_high_s16(diff_hi_s16)); - - a += 4 * a_stride; - b += 4 * b_stride; - } - - *sum = horizontal_add_s16x8(sum_s16); - *sse = (uint32_t)horizontal_add_s32x4(sse_s32); -} - -// Process a block of any size where the width is divisible by 16. -static void variance_neon_w16(const uint8_t *a, int a_stride, const uint8_t *b, - int b_stride, int w, int h, uint32_t *sse, - int *sum) { - const int32x4_t zero = vdupq_n_s32(0); - int16x8_t sum_s16 = vreinterpretq_s16_s32(zero); - int32x4_t sse_s32 = zero; - - // The loop loads 16 values at a time but doubles them up when accumulating - // into sum_s16. - assert(w / 8 * h <= 128); - - int i, j; - for (i = 0; i < h; ++i) { - for (j = 0; j < w; j += 16) { - const uint8x16_t a_u8 = vld1q_u8(a + j); - const uint8x16_t b_u8 = vld1q_u8(b + j); - - const int16x8_t diff_lo_s16 = - vreinterpretq_s16_u16(vsubl_u8(vget_low_u8(a_u8), vget_low_u8(b_u8))); - const int16x8_t diff_hi_s16 = vreinterpretq_s16_u16( - vsubl_u8(vget_high_u8(a_u8), vget_high_u8(b_u8))); - - sum_s16 = vaddq_s16(sum_s16, diff_lo_s16); - sum_s16 = vaddq_s16(sum_s16, diff_hi_s16); - - sse_s32 = vmlal_s16(sse_s32, vget_low_s16(diff_lo_s16), - vget_low_s16(diff_lo_s16)); - sse_s32 = vmlal_s16(sse_s32, vget_high_s16(diff_lo_s16), - vget_high_s16(diff_lo_s16)); - - sse_s32 = vmlal_s16(sse_s32, vget_low_s16(diff_hi_s16), - vget_low_s16(diff_hi_s16)); - sse_s32 = vmlal_s16(sse_s32, vget_high_s16(diff_hi_s16), - vget_high_s16(diff_hi_s16)); - } - a += a_stride; - b += b_stride; - } - - *sum = horizontal_add_s16x8(sum_s16); - *sse = (uint32_t)horizontal_add_s32x4(sse_s32); -} - -// Process a block of width 8 two rows at a time. -static void variance_neon_w8x2(const uint8_t *a, int a_stride, const uint8_t *b, - int b_stride, int h, uint32_t *sse, int *sum) { - const int32x4_t zero = vdupq_n_s32(0); - int16x8_t sum_s16 = vreinterpretq_s16_s32(zero); - int32x4_t sse_s32 = zero; - - // Each column has it's own accumulator entry in sum_s16. - assert(h <= 128); - - int i = 0; - do { - const uint8x8_t a_0_u8 = vld1_u8(a); - const uint8x8_t a_1_u8 = vld1_u8(a + a_stride); - const uint8x8_t b_0_u8 = vld1_u8(b); - const uint8x8_t b_1_u8 = vld1_u8(b + b_stride); - const int16x8_t diff_0_s16 = - vreinterpretq_s16_u16(vsubl_u8(a_0_u8, b_0_u8)); - const int16x8_t diff_1_s16 = - vreinterpretq_s16_u16(vsubl_u8(a_1_u8, b_1_u8)); - sum_s16 = vaddq_s16(sum_s16, diff_0_s16); - sum_s16 = vaddq_s16(sum_s16, diff_1_s16); - sse_s32 = - vmlal_s16(sse_s32, vget_low_s16(diff_0_s16), vget_low_s16(diff_0_s16)); - sse_s32 = - vmlal_s16(sse_s32, vget_low_s16(diff_1_s16), vget_low_s16(diff_1_s16)); - sse_s32 = vmlal_s16(sse_s32, vget_high_s16(diff_0_s16), - vget_high_s16(diff_0_s16)); - sse_s32 = vmlal_s16(sse_s32, vget_high_s16(diff_1_s16), - vget_high_s16(diff_1_s16)); - a += a_stride + a_stride; - b += b_stride + b_stride; - i += 2; - } while (i < h); - - *sum = horizontal_add_s16x8(sum_s16); - *sse = (uint32_t)horizontal_add_s32x4(sse_s32); -} - -#define VARIANCE_NXM(n, m, shift) \ - unsigned int aom_variance##n##x##m##_neon(const uint8_t *a, int a_stride, \ - const uint8_t *b, int b_stride, \ - unsigned int *sse) { \ - int sum; \ - if (n == 4) \ - variance_neon_w4x4(a, a_stride, b, b_stride, m, sse, &sum); \ - else if (n == 8) \ - variance_neon_w8x2(a, a_stride, b, b_stride, m, sse, &sum); \ - else \ - variance_neon_w16(a, a_stride, b, b_stride, n, m, sse, &sum); \ - if (n * m < 16 * 16) \ - return *sse - ((sum * sum) >> shift); \ - else \ - return *sse - (uint32_t)(((int64_t)sum * sum) >> shift); \ - } - -static void variance_neon_wide_block(const uint8_t *a, int a_stride, - const uint8_t *b, int b_stride, int w, - int h, uint32_t *sse, int *sum) { - const int32x4_t zero = vdupq_n_s32(0); - int32x4_t v_diff = zero; - int64x2_t v_sse = vreinterpretq_s64_s32(zero); - - int s, i, j; - for (s = 0; s < 16; s++) { - int32x4_t sse_s32 = zero; - int16x8_t sum_s16 = vreinterpretq_s16_s32(zero); - for (i = (s * h) >> 4; i < (((s + 1) * h) >> 4); ++i) { - for (j = 0; j < w; j += 16) { - const uint8x16_t a_u8 = vld1q_u8(a + j); - const uint8x16_t b_u8 = vld1q_u8(b + j); - - const int16x8_t diff_lo_s16 = vreinterpretq_s16_u16( - vsubl_u8(vget_low_u8(a_u8), vget_low_u8(b_u8))); - const int16x8_t diff_hi_s16 = vreinterpretq_s16_u16( - vsubl_u8(vget_high_u8(a_u8), vget_high_u8(b_u8))); - - sum_s16 = vaddq_s16(sum_s16, diff_lo_s16); - sum_s16 = vaddq_s16(sum_s16, diff_hi_s16); - - sse_s32 = vmlal_s16(sse_s32, vget_low_s16(diff_lo_s16), - vget_low_s16(diff_lo_s16)); - sse_s32 = vmlal_s16(sse_s32, vget_high_s16(diff_lo_s16), - vget_high_s16(diff_lo_s16)); - sse_s32 = vmlal_s16(sse_s32, vget_low_s16(diff_hi_s16), - vget_low_s16(diff_hi_s16)); - sse_s32 = vmlal_s16(sse_s32, vget_high_s16(diff_hi_s16), - vget_high_s16(diff_hi_s16)); - } - - a += a_stride; - b += b_stride; - } - - v_diff = vpadalq_s16(v_diff, sum_s16); - v_sse = vpadalq_s32(v_sse, sse_s32); - } - int diff = horizontal_add_s32x4(v_diff); -#if defined(__aarch64__) - uint32_t sq = (uint32_t)vaddvq_u64(vreinterpretq_u64_s64(v_sse)); -#else - uint32_t sq = vget_lane_u32( - vreinterpret_u32_s64(vadd_s64(vget_low_s64(v_sse), vget_high_s64(v_sse))), - 0); -#endif - - *sum = diff; - *sse = sq; -} - -#define VARIANCE_NXM_WIDE(W, H) \ - unsigned int aom_variance##W##x##H##_neon(const uint8_t *a, int a_stride, \ - const uint8_t *b, int b_stride, \ - uint32_t *sse) { \ - int sum; \ - variance_neon_wide_block(a, a_stride, b, b_stride, W, H, sse, &sum); \ - return *sse - (uint32_t)(((int64_t)sum * sum) / (W * H)); \ - } - -VARIANCE_NXM(4, 4, 4) -VARIANCE_NXM(4, 8, 5) -VARIANCE_NXM(8, 4, 5) -VARIANCE_NXM(16, 32, 9) -VARIANCE_NXM(32, 16, 9) -VARIANCE_NXM_WIDE(128, 64) -VARIANCE_NXM_WIDE(64, 128)