Drop Default requirement on ByteValued #274
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Ablu
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stsquad
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Dec 6, 2023
roypat
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Yeah, this makes sense to me, I've thought about it before. Maybe, given that there's been issues with implementing this trait, and we have #246, long term it might make sense for us to just use the zerocopy crate in vm-memory, to replace ByteValued 🤔 Although one would have to check if it can deal with volatile memory
epilys
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Dec 7, 2023
Since zeros are a valid value for any ByteValued type, we can use that instead of relying on a Default implementation (which may not be auto-derivable for some array types). Further optimizations would be possible if we would have access to a pointer value into the source data. Then we could also use ptr::copy_nonoverlapping and avoid pre-initialization altogether. But changing the API just for that seems a bit excessive. Signed-off-by: Erik Schilling <[email protected]>
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Since zeros are a valid value for any ByteValued type, we can use that instead of relying on a Default implementation (which may not be auto-derivable for some array types).
Further optimizations would be possible if we would have access to a pointer value into the source data. Then we could also use ptr::copy_nonoverlapping and avoid pre-initialization altogether. But changing the API just for that seems a bit excessive.
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