[FFmpeg-devel] [PATCH 4/4] lavc/aarch64: clean-up sao band 8x8 function formatting

[J. Dekker]

Signed-off-by: J. Dekker <jdek at itanimul.li>
---
 libavcodec/aarch64/hevcdsp_sao_neon.S | 103 +++++++++++---------------
 1 file changed, 44 insertions(+), 59 deletions(-)

diff --git a/libavcodec/aarch64/hevcdsp_sao_neon.S b/libavcodec/aarch64/hevcdsp_sao_neon.S
index 263747149f..c2519da7f5 100644
--- a/libavcodec/aarch64/hevcdsp_sao_neon.S
+++ b/libavcodec/aarch64/hevcdsp_sao_neon.S
@@ -3,7 +3,7 @@
  *
  * AArch64 NEON optimised SAO functions for HEVC decoding
  *
- * Copyright (c) 2020 Josh Dekker <josh at itanimul.li>
+ * Copyright (c) 2020-2021  J. Dekker <jdek at itanimul.li>
  *
  * This file is part of FFmpeg.
  *
@@ -29,64 +29,49 @@
 //                      int16_t *sao_offset_val, int sao_left_class,
 //                      int width, int height)
 function ff_hevc_sao_band_filter_8x8_8_neon, export=1
-        sub             sp,  sp, #64
-        stp            xzr, xzr, [sp]
-        stp            xzr, xzr, [sp, #16]
-        stp            xzr, xzr, [sp, #32]
-        stp            xzr, xzr, [sp, #48]
-        mov             w8,  #4
-        sxtw            x6,  w6
-0:
-        ldrsh           x9, [x4,  x8, lsl #1] // x9 = sao_offset_val[k+1]
-        subs            w8,  w8,  #1
-        add            w10,  w8,  w5 // x10 = k + sao_left_class
-        and            w10, w10, #0x1F
-        strh            w9, [sp, x10, lsl #1]
-        bne             0b
-        ld1            {v16.16b-v19.16b}, [sp], #64
-        movi           v20.8h,   #1
-        sub             x2,  x2, x6 // stride_dst - width
-        sub             x3,  x3, x6 // stride_src - width
-1:      // beginning of line
-        mov             x8,  x6
-2:
-        // Simple layout for accessing 16bit values
-        // with 8bit LUT.
-        //
-        //   00  01  02  03  04  05  06  07
-        // +----------------------------------->
-        // |xDE#xAD|xCA#xFE|xBE#xEF|xFE#xED|....
-        // +----------------------------------->
-        //    i-0     i-1     i-2     i-3
-        // dst[x] = av_clip_pixel(src[x] + offset_table[src[x] >> shift]);
-        ld1            {v2.8b}, [x1], #8
-        // load src[x]
-        uxtl            v0.8h,  v2.8b
-        // >> shift
-        ushr            v2.8h,  v0.8h, #3 // BIT_DEPTH - 3
-        // x2 (access lower short)
-        shl             v1.8h,  v2.8h, #1 // low (x2, accessing short)
-        // +1 access upper short
-        add             v3.8h,  v1.8h, v20.8h
-        // shift insert index to upper byte
-        sli             v1.8h,  v3.8h, #8
-        // table
-        tbx            v2.16b, {v16.16b-v19.16b}, v1.16b
-        // src[x] + table
-        add             v1.8h,  v0.8h, v2.8h
-        // clip + narrow
-        sqxtun          v4.8b,  v1.8h
-        // store
-        st1            {v4.8b}, [x0], #8
-        // done 8 pixels
-        subs            w8, w8,  #8
-        bne             2b
-        // finished line
-        subs            w7, w7,  #1
-        add             x0, x0,  x2 // dst += stride_dst
-        add             x1, x1,  x3 // src += stride_src
-        bne             1b
-        ret
+       sub             sp,  sp, #64
+       stp            xzr, xzr, [sp]
+       stp            xzr, xzr, [sp, #16]
+       stp            xzr, xzr, [sp, #32]
+       stp            xzr, xzr, [sp, #48]
+       mov             w8,  #4
+       sxtw            x6,  w6
+0:     ldrsh           x9, [x4,  x8, lsl #1]      // sao_offset_val[k+1]
+       subs            w8,  w8,  #1
+       add            w10,  w8,  w5               // k + sao_left_class
+       and            w10, w10, #0x1F
+       strh            w9, [sp, x10, lsl #1]
+       bne             0b
+       ld1            {v16.16b-v19.16b}, [sp], #64
+       movi           v20.8h,   #1
+       sub             x2,  x2, x6                // stride_dst - width
+       sub             x3,  x3, x6                // stride_src - width
+1:     mov             x8,  x6                    // beginning of line
+2:     // Simple layout for accessing 16bit values
+       // with 8bit LUT.
+       //
+       //   00  01  02  03  04  05  06  07
+       // +----------------------------------->
+       // |xDE#xAD|xCA#xFE|xBE#xEF|xFE#xED|....
+       // +----------------------------------->
+       //    i-0     i-1     i-2     i-3
+       ld1            {v2.8b}, [x1], #8           // dst[x] = av_clip_pixel(src[x] + offset_table[src[x] >> shift]);
+       uxtl            v0.8h,  v2.8b              // load src[x]
+       ushr            v2.8h,  v0.8h, #3          // >> BIT_DEPTH - 3
+       shl             v1.8h,  v2.8h, #1          // low (x2, accessing short)
+       add             v3.8h,  v1.8h, v20.8h      // +1 access upper short
+       sli             v1.8h,  v3.8h, #8          // shift insert index to upper byte
+       tbx            v2.16b, {v16.16b-v19.16b}, v1.16b // table
+       add             v1.8h,  v0.8h, v2.8h       // src[x] + table
+       sqxtun          v4.8b,  v1.8h              // clip + narrow
+       st1            {v4.8b}, [x0], #8           // store
+       subs            w8, w8,  #8                // done 8 pixels
+       bne             2b
+       subs            w7, w7,  #1                // finished line, prep. new
+       add             x0, x0,  x2                // dst += stride_dst
+       add             x1, x1,  x3                // src += stride_src
+       bne             1b
+       ret
 endfunc
 
 // ASSUMES STRIDE_SRC = 192
-- 
2.30.1 (Apple Git-130)