diff options
author | Ronald S. Bultje <rsbultje@gmail.com> | 2015-10-23 11:11:53 -0400 |
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committer | Ronald S. Bultje <rsbultje@gmail.com> | 2015-10-24 14:34:50 -0400 |
commit | 52f84d82bdf1851ecfcc412c1719e5f6f3396209 (patch) | |
tree | 63451deab3c0da41c136f6eb249f04c973ad1e79 | |
parent | 683462911db5ba1b17c32c523cdefe921f5aaf17 (diff) | |
download | ffmpeg-52f84d82bdf1851ecfcc412c1719e5f6f3396209.tar.gz |
videodsp: don't overread edges in vfix3 emu_edge.
Fixes trac ticket 3226. Also see Andreas' analysis in
https://bugs.debian.org/801745, which was very helpful.
-rw-r--r-- | libavcodec/x86/videodsp.asm | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/libavcodec/x86/videodsp.asm b/libavcodec/x86/videodsp.asm index 25d43640ab..48f5ac0ce6 100644 --- a/libavcodec/x86/videodsp.asm +++ b/libavcodec/x86/videodsp.asm @@ -194,8 +194,12 @@ hvar_fn %elif (%2-%%off) == 2 mov valw, [srcq+%2-2] %elifidn %1, body - mov vald, [srcq+%2-3] -%else + mov valb, [srcq+%2-1] + sal vald, 16 + mov valw, [srcq+%2-3] +%elifidn %1, bottom + movd mm %+ %%mmx_idx, [srcq+%2-4] +%else ; top movd mm %+ %%mmx_idx, [srcq+%2-3] %endif %endif ; (%2-%%off) >= 1 @@ -251,12 +255,15 @@ hvar_fn mov [dstq+%2-2], valw %elifidn %1, body mov [dstq+%2-3], valw - shr vald, 16 + sar vald, 16 mov [dstq+%2-1], valb %else movd vald, mm %+ %%mmx_idx +%ifidn %1, bottom + sar vald, 8 +%endif mov [dstq+%2-3], valw - shr vald, 16 + sar vald, 16 mov [dstq+%2-1], valb %endif %endif ; (%2-%%off) >= 1 |