Instead of going byte by byte, copy entire blocks at once and only check
if we need to update the state once per block. This pretty much
eliminates `::update()` from profiles and measurably improves
performance for utilities like `sha256sum`.
PVS-Studio flagged this, as memset can be optimized away by the compiler
in some cases. We obviously don't want that to ever happen so make sure
to always use `explicit_bzero(..)` which can't be optimized away.
SPDX License Identifiers are a more compact / standardized
way of representing file license information.
See: https://spdx.dev/resources/use/#identifiers
This was done with the `ambr` search and replace tool.
ambr --no-parent-ignore --key-from-file --rep-from-file key.txt rep.txt *
Problem:
- `constexpr` functions are additionally decorated with `inline`
keyword. This is redundant since `constexpr` implies `inline`.
Solution:
- Remove redundancies.
