OP mentions "playing around with variable-length integer encodings."
`(63 - nlz) / 7` presumably tells you how many bytes you need to read for the varint. The length could be signaled by the number of leading zeros in the first byte (nlz), and each subsequent byte could set a high continuation bit (à la UTF-8 and protobuf varints), thus providing 7 bits of information per byte.
I'm totally speculating but this is generally what I'd expect from the expression `(63 - nlz) / 7` in the context of varints. Continuation bits and leading-zero-counters are redundant but this wouldn't be the first time I've seen something encode redundant information.
`(63 - nlz) / 7` presumably tells you how many bytes you need to read for the varint. The length could be signaled by the number of leading zeros in the first byte (nlz), and each subsequent byte could set a high continuation bit (à la UTF-8 and protobuf varints), thus providing 7 bits of information per byte.
I'm totally speculating but this is generally what I'd expect from the expression `(63 - nlz) / 7` in the context of varints. Continuation bits and leading-zero-counters are redundant but this wouldn't be the first time I've seen something encode redundant information.