The intention behind this commit is to reduce the use of Host.h/Host.cpp
in Support, to where it is only necessary.
In this case, the endian-detection and support functionality needed by
these implementations can be provided by `Support/SwapByteOrder.h` in a
cleaner manner.
This patch also changes the byte swap in SHA256.cpp to use the byte swap
function from that header, rather than an inlined implementation.
Differential Revision: https://reviews.llvm.org/D137834
Returning `std::array<uint8_t, N>` is better ergonomics for the hashing functions usage, instead of a `StringRef`:
* When returning `StringRef`, client code is "jumping through hoops" to do string manipulations instead of dealing with fixed array of bytes directly, which is more natural
* Returning `std::array<uint8_t, N>` avoids the need for the hasher classes to keep a field just for the purpose of wrapping it and returning it as a `StringRef`
As part of this patch also:
* Introduce `TruncatedBLAKE3` which is useful for using BLAKE3 as the hasher type for `HashBuilder` with non-default hash sizes.
* Make `MD5Result` inherit from `std::array<uint8_t, 16>` which improves & simplifies its API.
Differential Revision: https://reviews.llvm.org/D123100
Adds an *unaudited* SHA-256 implementation to `llvm/Support`. The ongoing lld-macho effort needs this to emit an adhoc code signature for macho files on macOS Big Sur.
Reviewed By: mehdi_amini
Differential Revision: https://reviews.llvm.org/D96540
