Artifacts in YUV420 conversion

[Senryoku]

Video playback using YUV420 hardware conversion shows weird (mostly) green artifacts. Seems to only appear when there's movement.

Does the software launch a conversion then starts streaming data in RAM, counting on the processing/transfer time? I'm currently processing all macro blocks immediately, should I process them one by one with some delay? Or maybe it's decompressing and there are floating point issues?

It goes away when using the interpreter.

Mostly still image:

Moving up:

[Senryoku]

Forcing mov.w @Rm+, Rn to fallback to the interpreter modifies the issue. This might indicate an issue with this instruction, or an issue with the register cache.

[Senryoku]

Forcing a fallback (and a cache flush) for all of them fixes the issue:

movb_atRmInc_Rn
movw_atRmInc_Rn
movl_atRmInc_Rn

movb_Rm_atRnDec
movw_Rm_atRnDec
movl_Rm_atRnDec

movb_atDispRm_R0
movw_atDispRm_R0
movl_atDispRm_Rn

movb_R0_atDispRm
movw_R0_atDispRm
movl_Rm_atDispRn

[Senryoku]

Using interpreter_fallback_cached as a fallback modifies the issue in the same way as a full fallback of mov.w @Rm+, Rn (flushing all cached values) without eliminating it completely, suggesting that this is indeed a cache issue in another instruction :(