I'm adding the i32::MAX test case here because I personally screwed it
up while I was working on
https://github.com/BLAKE3-team/BLAKE3/issues/271. The correct
implementation of the carry bit is the ANDNOT of old high bit (1) and
the new high bit (0). Using XOR instead of ANDNOT gives the correct
answer in the overflow case, but it also reports an incorrect "extra"
overflow when the high bit goes from 0 to 1.
This will let us add big endian testing to CI for our C code. (We were
already doing it for our Rust code.)
This is adapted from test_vectors/cross_test.sh. It works around the
limitation that the `cross` tool can't reach parent directories. It's an
unfortunate hack, but at least it's only for testing. It might've been
less hacky to use symlinks for this somehow, but I worry that would
break things on Windows, and I don't want to have to add workarounds for
my workarounds.
Wire up basic functions and features for SSE2 support using the SSE4.1 version
as a basis without implementing the SSE2 instructions yet.
* Cargo.toml: add no_sse2 feature
* benches/bench.rs: wire SSE2 benchmarks
* build.rs: add SSE2 rust intrinsics and assembly builds
* c/Makefile.testing: add SSE2 C and assembly targets
* c/README.md: add SSE2 to C build instructions
* c/blake3_c_rust_bindings/build.rs: add SSE2 C rust binding builds
* c/blake3_c_rust_bindings/src/lib.rs: add SSE2 C rust bindings
* c/blake3_dispatch.c: add SSE2 C dispatch
* c/blake3_impl.h: add SSE2 C function prototypes
* c/blake3_sse2.c: add SSE2 C intrinsic file starting with SSE4.1 version
* c/blake3_sse2_x86-64_{unix.S,windows_gnu.S,windows_msvc.asm}: add SSE2
assembly files starting with SSE4.1 version
* src/ffi_sse2.rs: add rust implementation using SSE2 C rust bindings
* src/lib.rs: add SSE2 rust intrinsics and SSE2 C rust binding rust SSE2 module
configurations
* src/platform.rs: add SSE2 rust platform detection and dispatch
* src/rust_sse2.rs: add SSE2 rust intrinsic file starting with SSE4.1 version
* tools/instruction_set_support/src/main.rs: add SSE2 feature detection
The biggest change here is that assembly implementations are enabled by
default.
Added features:
- "pure" (Pure Rust, with no C or assembly implementations.)
Removed features:
- "c" (Now basically the default.)
Renamed features;
- "c_prefer_intrinsics" -> "prefer_intrinsics"
- "c_neon" -> "neon"
Unchanged:
- "rayon"
- "std" (Still the only feature on by default.)
If the total number of chunks hashed so far is e.g. 1, and update() is
called with e.g. 8 more chunks, we can't compress all 8 together. We
have to break the input up, to make sure that that 1 lone chunk CV gets
merged with its proper sibling, and that in general the correct layout
of the tree is preserved. What we should do is hash 1-2-4-1 chunks of
input, using increasing powers of 2 (with some cleanup at the end). What
we were doing was 2-2-2-2 chunks. This was the result of a mistaken
optimization that got us stuck with an always-odd number of chunks so
far.
Fixes https://github.com/BLAKE3-team/BLAKE3/issues/69.
This gives the assembly files the same prefix as the intrinsics files which
simplifies building when the build system should pick between the assembly and
the intrinsics files.
One thing I like to test is that, if I hack simd_degree to be higher
than MAX_SIMD_DEGREE, assertions fire. This requires a test case long
enough to exceed that number of chunks.