Hi, 2011/7/3 Måns Rullgård <[email protected]>: > Daniel Kang <[email protected]> writes: > >> 2011/7/3 Måns Rullgård <[email protected]> >> >>> "Ronald S. Bultje" <[email protected]> writes: >>> >>> > Hi, >>> > >>> > 2011/7/3 Måns Rullgård <[email protected]>: >>> >> The AES and DES functions currently require, but do not document it, >>> >> 8-byte alignment for input and output buffers. This is causing the AES >>> >> test to fail on SPARC. >>> >> >>> >> What shall we do about this? I can see two options: >>> >> >>> >> 1. Document the requirement and fix all internal uses to ensure it is >>> >> met (none currently do). >>> >> >>> >> 2. Change the crypto code to allow arbitrarily aligned buffers (easy). >>> > >>> > I prefer 1, but don't strongly object to 2. >>> >>> The performance impact of allowing unaligned buffers should be minimal, >>> so I don't see much reason to place this extra burden on users. >> >> How minimal? Either way is fine with me though. > > I didn't measure it, but most of the time is spent in the actual > algorithm, not in loading and storing data.
Since realigning means copying in some cases (e.g. where data comes from a bytestream), unaligned is fine. Ronald _______________________________________________ libav-devel mailing list [email protected] https://lists.libav.org/mailman/listinfo/libav-devel
