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avcodec/x86/hpeldsp: fix crash on AMD K6-3+

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There are instructions pavgb and pavgusb. Both instructions do the same
operation but they have different enconding. Pavgb exists in SSE (or
MMXEXT) instruction set and pavgusb exists in 3D-NOW instruction set.

livavcodec uses the macro PAVGB to select the proper instruction. However,
the function avg_pixels8_xy2 doesn't use this macro, it uses pavgb
directly.

As a consequence, the function avg_pixels8_xy2 crashes on AMD K6-2 and
K6-3 processors, because they have pavgusb, but not pavgb.

This bug seems to be introduced by commit
71155d7b41, "dsputil: x86: Convert mpeg4
qpel and dsputil avg to yasm"

Signed-off-by: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
Mikulas Patocka 2013-11-03 18:00:17 +01:00 committed by Michael Niedermayer
parent 535d58959d
commit 074155360d
1 changed files with 13 additions and 13 deletions
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26
libavcodec/x86/hpeldsp.asm
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@ -423,30 +423,30 @@ cglobal avg_pixels8_xy2, 4,5
mova m6, [pb_1]
lea r4, [r2*2]
mova m0, [r1]
pavgb m0, [r1+1]
PAVGB m0, [r1+1]
.loop:
mova m2, [r1+r4]
mova m1, [r1+r2]
psubusb m2, m6
pavgb m1, [r1+r2+1]
pavgb m2, [r1+r4+1]
PAVGB m1, [r1+r2+1]
PAVGB m2, [r1+r4+1]
add r1, r4
pavgb m0, m1
pavgb m1, m2
pavgb m0, [r0]
pavgb m1, [r0+r2]
PAVGB m0, m1
PAVGB m1, m2
PAVGB m0, [r0]
PAVGB m1, [r0+r2]
mova [r0], m0
mova [r0+r2], m1
mova m1, [r1+r2]
mova m0, [r1+r4]
pavgb m1, [r1+r2+1]
pavgb m0, [r1+r4+1]
PAVGB m1, [r1+r2+1]
PAVGB m0, [r1+r4+1]
add r0, r4
add r1, r4
pavgb m2, m1
pavgb m1, m0
pavgb m2, [r0]
pavgb m1, [r0+r2]
PAVGB m2, m1
PAVGB m1, m0
PAVGB m2, [r0]
PAVGB m1, [r0+r2]
mova [r0], m2
mova [r0+r2], m1
add r0, r4