Consider an invalid instruction the end of a function trace#11
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KallDrexx merged 1 commit intoApfelTeeSaft:mainfrom Oct 12, 2025
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When tracing a function, previously we were throwing an exception if we encountered an invalid / unknown op code. This is needed because we don't know how many bytes the instruction contains and thus can't accurately predict where the next instruction would be. However, some roms (like super mario bros) use an always taken branch instruction to save bytes instead of a jump. In this case the next byte after the branch is an invalid op code that will never actually be hit. So this change makes it so that invalid operations act as an end of function markers, but throw a warning in the console. That allows unconditional/always branches to work, and for games that actually use these unofficial op codes they are able to get hints in the debug window.
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When tracing a function, previously we were throwing an exception if we encountered an invalid / unknown op code. This is needed because we don't know how many bytes the instruction contains and thus can't accurately predict where the next instruction would be.
However, some roms (like super mario bros) use an always taken branch instruction to save bytes instead of a jump. In this case the next byte after the branch is an invalid op code that will never actually be hit.
So this change makes it so that invalid operations act as an end of function markers, but throw a warning in the console. That allows unconditional/always branches to work, and for games that actually use these unofficial op codes they are able to get hints in the debug window.