Implement a direct murmur hash on values that omits type references #5884
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So, obviously it depends what you're hashing. But some quick tests suggest this is in fact a lot faster. Like, If you hash The old |
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Okay, I think this is finally in a mergeable state. |
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This implements a new builtin that does a murmur hash more directly on a value, and omitting several
Referenceoccurrences that are just for type information. The hope is that this will be quicker than serializing to bytes and then hashing the bytes.It's possible that even using the type information could be faster with some of the new machinery, because
References are lifted out when you create aValuenow, and I use that to pass around arrays ofHash64 -> Hash64functions that augment the hash with the reference information. But, I think the way the API is structured doesn't allow it to precompute a small value to add for each reference, and instead it's just a closure that does the full work every time.