ffmpeg | branch: master | Rémi Denis-Courmont <r...@remlab.net> | Thu Jun 27 22:00:05 2024 +0300| [b818dff8d8e16f0831a379a5cdc15e813474a841] | committer: Rémi Denis-Courmont
lavc/vc1dsp: fix potential overflow in R-V V inv_trans_4 Judging by the coefficients, the last round of add/sub can overflow to 17 bits with a very small probability just as with the 8-point transform. This is not observed under FATE, but better safe than sorry. > http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=b818dff8d8e16f0831a379a5cdc15e813474a841 --- libavcodec/riscv/vc1dsp_rvv.S | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) diff --git a/libavcodec/riscv/vc1dsp_rvv.S b/libavcodec/riscv/vc1dsp_rvv.S index 0e89e29a1d..9d85377cec 100644 --- a/libavcodec/riscv/vc1dsp_rvv.S +++ b/libavcodec/riscv/vc1dsp_rvv.S @@ -202,13 +202,14 @@ func ff_vc1_inv_trans_4_rvv, zve32x vmul.vx v20, v1, t2 vadd.vv v26, v14, v16 # t3 vsub.vv v27, v18, v20 # t4 - vadd.vv v0, v24, v26 - vsub.vv v1, v25, v27 - vadd.vv v2, v25, v27 - vsub.vv v3, v24, v26 - .irp n,0,1,2,3 - vssra.vx v\n, v\n, t1 # + 4 >> 3 or + 64 >> 7 - .endr + vwadd.vv v8, v24, v26 + vwsub.vv v10, v25, v27 + vwadd.vv v12, v25, v27 + vwsub.vv v14, v24, v26 + vnclip.wx v0, v8, t1 + vnclip.wx v1, v10, t1 + vnclip.wx v2, v12, t1 + vnclip.wx v3, v14, t1 jr t0 endfunc _______________________________________________ ffmpeg-cvslog mailing list ffmpeg-cvslog@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-cvslog To unsubscribe, visit link above, or email ffmpeg-cvslog-requ...@ffmpeg.org with subject "unsubscribe".
