On Mon, Jan 24, 2022 at 09:10:38PM -0800, Eric Biggers wrote: > On Mon, Jan 24, 2022 at 08:01:03AM -0800, Keith Busch wrote: > > Since this model reflects inputs and outputs, a helper table and > > function are added to reverse bits of 8 and 64 bit values. > > That's a silly way to do a bit-reflected CRC. The proper way to do it is to > reflect the bytes too, so that the bits and bytes are ordered consistently, so > explicitly reflecting the bits isn't needed. Most CRC-32's are bit-reflected, > and they are usually implemented this way. E.g., see crc32_le() in lib/crc32.c. > > Here's a Python script that shows that the Rocksoft CRC-64 can be computed > without explicitly reversing the bits. It passes the tests from your patch 4: Thanks for the tip! I'll use that for the next version.
