[FFmpeg-cvslog] lavc/arm: dont assign hevc_qpel functions for non-multiple of 8 widths

[J. Dekker]

ffmpeg | branch: master | J. Dekker <jdek at itanimul.li> | Sat Oct 16 19:35:51 2021 +0200| [22b7c37275c611b5417722d8941844028aed7f25] | committer: J. Dekker

lavc/arm: dont assign hevc_qpel functions for non-multiple of 8 widths

The assembly is written assuming that the width is a multiple of 8.

However the real issue is the functions were errorneously assigned to
the 2, 4, 6 & 12 widths. This behaviour never broke the decoder as
samples which trigger the functions for these widths have not been found
in the wild. This relies on the mappings in ff_hevc_pel_weight[].

Signed-off-by: J. Dekker <jdek at itanimul.li>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=22b7c37275c611b5417722d8941844028aed7f25
---

 libavcodec/arm/hevcdsp_init_neon.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/libavcodec/arm/hevcdsp_init_neon.c b/libavcodec/arm/hevcdsp_init_neon.c
index 201a088dac..112edb5edd 100644
--- a/libavcodec/arm/hevcdsp_init_neon.c
+++ b/libavcodec/arm/hevcdsp_init_neon.c
@@ -270,7 +270,8 @@ av_cold void ff_hevc_dsp_init_neon(HEVCDSPContext *c, const int bit_depth)
         put_hevc_qpel_uw_neon[3][1]      = ff_hevc_put_qpel_uw_h1v3_neon_8;
         put_hevc_qpel_uw_neon[3][2]      = ff_hevc_put_qpel_uw_h2v3_neon_8;
         put_hevc_qpel_uw_neon[3][3]      = ff_hevc_put_qpel_uw_h3v3_neon_8;
-        for (x = 0; x < 10; x++) {
+        for (x = 3; x < 10; x++) {
+            if (x == 4) continue;
             c->put_hevc_qpel[x][1][0]         = ff_hevc_put_qpel_neon_wrapper;
             c->put_hevc_qpel[x][0][1]         = ff_hevc_put_qpel_neon_wrapper;
             c->put_hevc_qpel[x][1][1]         = ff_hevc_put_qpel_neon_wrapper;