dst_ptr += 8 * dst_stride;
}
}
+
+// sum += x;
+// sumsq += x * y;
+static void accumulate_sum_sumsq(const int16x4_t x, const int32x4_t xy,
+ int16x4_t *const sum, int32x4_t *const sumsq) {
+ const int16x4_t zero = vdup_n_s16(0);
+ const int32x4_t zeroq = vdupq_n_s32(0);
+
+ // Add in the first set because vext doesn't work with '0'.
+ *sum = vadd_s16(*sum, x);
+ *sumsq = vaddq_s32(*sumsq, xy);
+
+ // Shift x and xy to the right and sum. vext requires an immediate.
+ *sum = vadd_s16(*sum, vext_s16(zero, x, 1));
+ *sumsq = vaddq_s32(*sumsq, vextq_s32(zeroq, xy, 1));
+
+ *sum = vadd_s16(*sum, vext_s16(zero, x, 2));
+ *sumsq = vaddq_s32(*sumsq, vextq_s32(zeroq, xy, 2));
+
+ *sum = vadd_s16(*sum, vext_s16(zero, x, 3));
+ *sumsq = vaddq_s32(*sumsq, vextq_s32(zeroq, xy, 3));
+}
+
+// Generate mask based on (sumsq * 15 - sum * sum < flimit)
+static uint16x4_t calculate_mask(const int16x4_t sum, const int32x4_t sumsq,
+ const int32x4_t f, const int32x4_t fifteen) {
+ const int32x4_t a = vmulq_s32(sumsq, fifteen);
+ const int32x4_t b = vmlsl_s16(a, sum, sum);
+ const uint32x4_t mask32 = vcltq_s32(b, f);
+ return vmovn_u32(mask32);
+}
+
+static uint8x8_t combine_mask(const int16x4_t sum_low, const int16x4_t sum_high,
+ const int32x4_t sumsq_low,
+ const int32x4_t sumsq_high, const int32x4_t f) {
+ const int32x4_t fifteen = vdupq_n_s32(15);
+ const uint16x4_t mask16_low = calculate_mask(sum_low, sumsq_low, f, fifteen);
+ const uint16x4_t mask16_high =
+ calculate_mask(sum_high, sumsq_high, f, fifteen);
+ return vmovn_u16(vcombine_u16(mask16_low, mask16_high));
+}
+
+// Apply filter of (8 + sum + s[c]) >> 4.
+static uint8x8_t filter_pixels(const int16x8_t sum, const uint8x8_t s) {
+ const int16x8_t s16 = vreinterpretq_s16_u16(vmovl_u8(s));
+ const int16x8_t sum_s = vaddq_s16(sum, s16);
+
+ return vqrshrun_n_s16(sum_s, 4);
+}
+
+void vpx_mbpost_proc_across_ip_neon(uint8_t *src, int pitch, int rows, int cols,
+ int flimit) {
+ int row, col;
+ const int32x4_t f = vdupq_n_s32(flimit);
+
+ assert(cols % 8 == 0);
+
+ for (row = 0; row < rows; ++row) {
+ // Sum the first 8 elements, which are extended from s[0].
+ // sumsq gets primed with +16.
+ int sumsq = src[0] * src[0] * 9 + 16;
+ int sum = src[0] * 9;
+
+ uint8x8_t left_context, s, right_context;
+ int16x4_t sum_low, sum_high;
+ int32x4_t sumsq_low, sumsq_high;
+
+ // Sum (+square) the next 6 elements.
+ // Skip [0] because it's included above.
+ for (col = 1; col <= 6; ++col) {
+ sumsq += src[col] * src[col];
+ sum += src[col];
+ }
+
+ // Prime the sums. Later the loop uses the _high values to prime the new
+ // vectors.
+ sumsq_high = vdupq_n_s32(sumsq);
+ sum_high = vdup_n_s16(sum);
+
+ // Manually extend the left border.
+ left_context = vdup_n_u8(src[0]);
+
+ for (col = 0; col < cols; col += 8) {
+ uint8x8_t mask, output;
+ int16x8_t x, y;
+ int32x4_t xy_low, xy_high;
+
+ s = vld1_u8(src + col);
+
+ if (col + 8 == cols) {
+ // Last row. Extend border.
+ right_context = vdup_n_u8(src[col + 7]);
+ } else {
+ right_context = vld1_u8(src + col + 7);
+ }
+
+ x = vreinterpretq_s16_u16(vsubl_u8(right_context, left_context));
+ y = vreinterpretq_s16_u16(vaddl_u8(right_context, left_context));
+ xy_low = vmull_s16(vget_low_s16(x), vget_low_s16(y));
+ xy_high = vmull_s16(vget_high_s16(x), vget_high_s16(y));
+
+ // Catch up to the last sum'd value.
+ sum_low = vdup_lane_s16(sum_high, 3);
+ sumsq_low = vdupq_lane_s32(vget_high_s32(sumsq_high), 1);
+
+ accumulate_sum_sumsq(vget_low_s16(x), xy_low, &sum_low, &sumsq_low);
+
+ // Need to do this sequentially because we need the max value from
+ // sum_low.
+ sum_high = vdup_lane_s16(sum_low, 3);
+ sumsq_high = vdupq_lane_s32(vget_high_s32(sumsq_low), 1);
+
+ accumulate_sum_sumsq(vget_high_s16(x), xy_high, &sum_high, &sumsq_high);
+
+ mask = combine_mask(sum_low, sum_high, sumsq_low, sumsq_high, f);
+
+ output = filter_pixels(vcombine_s16(sum_low, sum_high), s);
+ output = vbsl_u8(mask, output, s);
+
+ vst1_u8(src + col, output);
+
+ left_context = s;
+ }
+
+ src += pitch;
+ }
+}
projects / libvpx / commitdiff