diff --git a/libavcodec/aarch64/me_cmp_neon.S b/libavcodec/aarch64/me_cmp_neon.S index 0ae23d8922..89546869fb 100644 --- a/libavcodec/aarch64/me_cmp_neon.S +++ b/libavcodec/aarch64/me_cmp_neon.S @@ -124,6 +124,9 @@ function ff_pix_abs16_xy2_neon, export=1 add v26.8h, v30.8h, v2.8h // add up 0..7, using pix2 + pix2+1 values from pix3 above add v27.8h, v31.8h, v3.8h // add up 8..15, using pix2 + pix2+1 values from pix3 above + uabdl v24.8h, v1.8b, v23.8b // absolute difference 0..7, i=0 + uabdl2 v23.8h, v1.16b, v23.16b // absolute difference 8..15, i=0 + ld1 {v21.16b}, [x5], x3 // load pix3 ld1 {v20.16b}, [x1], x3 // load pix1 @@ -137,6 +140,9 @@ function ff_pix_abs16_xy2_neon, export=1 rshrn v28.8b, v28.8h, #2 // shift right 2 0..7 (rounding shift right) rshrn2 v28.16b, v29.8h, #2 // shift right 2 8..15 + uabal v24.8h, v16.8b, v26.8b // absolute difference 0..7, i=1 + uabal2 v23.8h, v16.16b, v26.16b // absolute difference 8..15, i=1 + uaddl v2.8h, v21.8b, v22.8b // pix3 + pix3+1 0..7 uaddl2 v3.8h, v21.16b, v22.16b // pix3 + pix3+1 8..15 add v30.8h, v4.8h, v2.8h // add up 0..7, using pix2 + pix2+1 values from pix3 above @@ -144,33 +150,17 @@ function ff_pix_abs16_xy2_neon, export=1 rshrn v30.8b, v30.8h, #2 // shift right 2 0..7 (rounding shift right) rshrn2 v30.16b, v31.8h, #2 // shift right 2 8..15 - // Averages are now stored in these registers: - // v23, v16, v28, v30 - // pix1 values in these registers: - // v1, v16, v17, v20 - // available: - // v4, v5, v7, v18, v19, v24, v25, v27, v29, v31 + uabal v24.8h, v17.8b, v28.8b // absolute difference 0..7, i=2 + uabal2 v23.8h, v17.16b, v28.16b // absolute difference 8..15, i=2 sub w4, w4, #4 // h -= 4 - // Using absolute-difference instructions instead of absolute-difference-accumulate allows - // us to keep the results in 16b vectors instead of widening values with twice the instructions. - // This approach also has fewer data dependencies, allowing better instruction level parallelism. - uabd v4.16b, v1.16b, v23.16b // absolute difference 0..15, i=0 - uabd v5.16b, v16.16b, v26.16b // absolute difference 0..15, i=1 - uabd v6.16b, v17.16b, v28.16b // absolute difference 0..15, i=2 - uabd v7.16b, v20.16b, v30.16b // absolute difference 0..15, i=3 + uabal v24.8h, v20.8b, v30.8b // absolute difference 0..7, i=3 + uabal2 v23.8h, v20.16b, v30.16b // absolute difference 8..15, i=3 cmp w4, #4 // loop if h >= 4 - // Now add up all the values in each vector, v4-v7 with widening adds - uaddl v19.8h, v4.8b, v5.8b - uaddl2 v18.8h, v4.16b, v5.16b - uaddl v4.8h, v6.8b, v7.8b - uaddl2 v5.8h, v6.16b, v7.16b - add v4.8h, v4.8h, v5.8h - add v4.8h, v4.8h, v18.8h - add v4.8h, v4.8h, v19.8h + add v4.8h, v23.8h, v24.8h uaddlv s4, v4.8h // finish adding up accumulated values add d0, d0, d4 // add the value to the top level accumulator