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Originally Posted by Mrs Beanbag
True. There is TRAPcc though...
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I recall you that TRAPcc doesn't work on 68000.
Quote:
Originally Posted by Mrs Beanbag
But they COULD have maintained exception behaviour on odd addresses the same as before, while allowing non-longword-aligned addresses. They don't *need* to anymore, and as such it might not be very meaningful. But they could have, for the sake of backwards compatibility, if they'd thought it was a legitimate thing to do on purpose.
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Sure they could have built a cpu that supports
some misaligned accesses. However it would have looked ridiculous, and very confusing (i even dare to say total crazy).
They did the right choice and it's good for coding flexibility, code density, and even sometimes performance. It was really worth the limited compatibility issue.
It's always a matter of trade-offs. Inability of the 68000 to do misaligned accesses was a real pain. Not many programs trigger address errors on purpose ; in fact i haven't found any. So the change is ok. On the other hand, even a very small compatibility threat for just a near useless branch hint bit, isn't worth.