Optimize Neon vertical Wiener convolve for 5-tap filters Wiener convolution filters can be either 5 or 7 taps. The current Neon implementation pads 5-tap filters with zeros to treat them as 7-tap filters. This patch adds a Neon path specialised for 5-tap vertical Wiener filters, avoiding the redundant work of using the 7-tap path with a 5-tap filter. Change-Id: If53c96828551789ac20751f6d73f3caaecd82971
diff --git a/av1/common/arm/wiener_convolve_neon.c b/av1/common/arm/wiener_convolve_neon.c index e4a59a1..6440c16 100644 --- a/av1/common/arm/wiener_convolve_neon.c +++ b/av1/common/arm/wiener_convolve_neon.c
@@ -129,6 +129,77 @@ } while (--h != 0); } +static INLINE uint8x8_t wiener_convolve5_8_2d_v( + const int16x8_t s0, const int16x8_t s1, const int16x8_t s2, + const int16x8_t s3, const int16x8_t s4, const int16x4_t y_filter, + const int32x4_t round_vec) { + // Since the Wiener filter is symmetric about the middle tap (tap 2) add + // mirrored source elements before multiplying by filter coefficients. + int16x8_t s04 = vaddq_s16(s0, s4); + int16x8_t s13 = vaddq_s16(s1, s3); + + int32x4_t sum_lo = vmlal_lane_s16(round_vec, vget_low_s16(s04), y_filter, 1); + sum_lo = vmlal_lane_s16(sum_lo, vget_low_s16(s13), y_filter, 2); + sum_lo = vmlal_lane_s16(sum_lo, vget_low_s16(s2), y_filter, 3); + + int32x4_t sum_hi = vmlal_lane_s16(round_vec, vget_high_s16(s04), y_filter, 1); + sum_hi = vmlal_lane_s16(sum_hi, vget_high_s16(s13), y_filter, 2); + sum_hi = vmlal_lane_s16(sum_hi, vget_high_s16(s2), y_filter, 3); + + int16x4_t res_lo = vshrn_n_s32(sum_lo, 2 * FILTER_BITS - WIENER_ROUND0_BITS); + int16x4_t res_hi = vshrn_n_s32(sum_hi, 2 * FILTER_BITS - WIENER_ROUND0_BITS); + + return vqmovun_s16(vcombine_s16(res_lo, res_hi)); +} + +static INLINE void convolve_add_src_vert_5tap_neon( + const uint16_t *src, ptrdiff_t src_stride, uint8_t *dst, + ptrdiff_t dst_stride, int w, int h, const int16x4_t y_filter, + const int32x4_t round_vec) { + do { + const int16_t *s = (int16_t *)src; + uint8_t *d = dst; + int height = h; + + while (height > 3) { + int16x8_t s0, s1, s2, s3, s4, s5, s6, s7; + load_s16_8x8(s, src_stride, &s0, &s1, &s2, &s3, &s4, &s5, &s6, &s7); + + uint8x8_t d0 = + wiener_convolve5_8_2d_v(s0, s1, s2, s3, s4, y_filter, round_vec); + uint8x8_t d1 = + wiener_convolve5_8_2d_v(s1, s2, s3, s4, s5, y_filter, round_vec); + uint8x8_t d2 = + wiener_convolve5_8_2d_v(s2, s3, s4, s5, s6, y_filter, round_vec); + uint8x8_t d3 = + wiener_convolve5_8_2d_v(s3, s4, s5, s6, s7, y_filter, round_vec); + + store_u8_8x4(d, dst_stride, d0, d1, d2, d3); + + s += 4 * src_stride; + d += 4 * dst_stride; + height -= 4; + } + + while (height-- != 0) { + int16x8_t s0, s1, s2, s3, s4; + load_s16_8x5(s, src_stride, &s0, &s1, &s2, &s3, &s4); + + uint8x8_t d0 = + wiener_convolve5_8_2d_v(s0, s1, s2, s3, s4, y_filter, round_vec); + + vst1_u8(d, d0); + + d += dst_stride; + s += src_stride; + } + + src += 8; + dst += 8; + w -= 8; + } while (w != 0); +} + static INLINE uint8x8_t wiener_convolve7_8_2d_v( const int16x8_t s0, const int16x8_t s1, const int16x8_t s2, const int16x8_t s3, const int16x8_t s4, const int16x8_t s5, @@ -155,18 +226,10 @@ return vqmovun_s16(vcombine_s16(res_lo, res_hi)); } -static INLINE void convolve_add_src_vert_hip_neon( +static INLINE void convolve_add_src_vert_7tap_neon( const uint16_t *src, ptrdiff_t src_stride, uint8_t *dst, - ptrdiff_t dst_stride, const int16_t *y_filter_ptr, int w, int h) { - const int bd = 8; - const int32x4_t round_vec = - vdupq_n_s32((1 << (2 * FILTER_BITS - WIENER_ROUND0_BITS - 1)) - - (1 << (bd + (2 * FILTER_BITS - WIENER_ROUND0_BITS) - 1))); - - int16x4_t y_filter = vld1_s16(y_filter_ptr); - // Add 128 to tap 3. (Needed for rounding.) - y_filter = vadd_s16(y_filter, vcreate_s16((1ULL << FILTER_BITS) << 48)); - + ptrdiff_t dst_stride, int w, int h, const int16x4_t y_filter, + const int32x4_t round_vec) { do { const int16_t *s = (int16_t *)src; uint8_t *d = dst; @@ -244,22 +307,29 @@ im_block[(MAX_SB_SIZE + WIENER_WIN - 1) * MAX_SB_SIZE]); const int x_filter_taps = get_wiener_filter_taps(x_filter); + const int y_filter_taps = get_wiener_filter_taps(y_filter); int16x4_t x_filter_s16 = vld1_s16(x_filter); + int16x4_t y_filter_s16 = vld1_s16(y_filter); // Add 128 to tap 3. (Needed for rounding.) x_filter_s16 = vadd_s16(x_filter_s16, vcreate_s16(128ULL << 48)); + y_filter_s16 = vadd_s16(y_filter_s16, vcreate_s16(128ULL << 48)); const int im_stride = MAX_SB_SIZE; - const int im_h = h + WIENER_WIN - 1; - const int horiz_offset = WIENER_HALFWIN; - const int vert_offset = WIENER_HALFWIN * (int)src_stride; + const int im_h = h + y_filter_taps - 1; + const int horiz_offset = x_filter_taps / 2; + const int vert_offset = (y_filter_taps / 2) * (int)src_stride; const int bd = 8; - const int32x4_t horiz_round_vec = vdupq_n_s32(1 << (bd + FILTER_BITS - 1)); const uint16x8_t im_max_val = vdupq_n_u16((1 << (bd + 1 + FILTER_BITS - WIENER_ROUND0_BITS)) - 1); + const int32x4_t horiz_round_vec = vdupq_n_s32(1 << (bd + FILTER_BITS - 1)); + + const int32x4_t vert_round_vec = + vdupq_n_s32((1 << (2 * FILTER_BITS - WIENER_ROUND0_BITS - 1)) - + (1 << (bd + (2 * FILTER_BITS - WIENER_ROUND0_BITS) - 1))); if (x_filter_taps == WIENER_WIN_REDUCED) { - convolve_add_src_horiz_5tap_neon(src - horiz_offset - vert_offset + 1, + convolve_add_src_horiz_5tap_neon(src - horiz_offset - vert_offset, src_stride, im_block, im_stride, w, im_h, x_filter_s16, horiz_round_vec, im_max_val); } else { @@ -268,6 +338,11 @@ x_filter_s16, horiz_round_vec, im_max_val); } - convolve_add_src_vert_hip_neon(im_block, im_stride, dst, dst_stride, y_filter, - w, h); + if (y_filter_taps == WIENER_WIN_REDUCED) { + convolve_add_src_vert_5tap_neon(im_block, im_stride, dst, dst_stride, w, h, + y_filter_s16, vert_round_vec); + } else { + convolve_add_src_vert_7tap_neon(im_block, im_stride, dst, dst_stride, w, h, + y_filter_s16, vert_round_vec); + } }