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This commit adds a new crate for testing that the intrinsics listed in this crate do indeed match the upstream definition of each intrinsic. A pre-downloaded XML description of all Intel intrinsics is checked in which is then parsed in the `stdsimd-verify` crate to verify that everything we write down is matched against the upstream definitions. Currently the checks are pretty loose to get this compiling but a few intrinsics were fixed as a result of this. For example: * `_mm256_extract_epi8` - AVX2 intrinsic erroneously listed under AVX * `_mm256_extract_epi16` - AVX2 intrinsic erroneously listed under AVX * `_mm256_extract_epi32` - AVX2 intrinsic erroneously listed under AVX * `_mm256_extract_epi64` - AVX2 intrinsic erroneously listed under AVX * `_mm_tzcnt_32` - erroneously had `u32` in the name * `_mm_tzcnt_64` - erroneously had `u64` in the name * `_mm_cvtsi64_si128` - erroneously available on 32-bit platforms * `_mm_cvtsi64x_si128` - erroneously available on 32-bit platforms * `_mm_cvtsi128_si64` - erroneously available on 32-bit platforms * `_mm_cvtsi128_si64x` - erroneously available on 32-bit platforms * `_mm_extract_epi64` - erroneously available on 32-bit platforms * `_mm_insert_epi64` - erroneously available on 32-bit platforms * `_mm256_extract_epi16` - erroneously returned i32 instead of i16 * `_mm256_extract_epi8` - erroneously returned i32 instead of i8 * `_mm_shuffle_ps` - the mask argument was erroneously i32 instead of u32 * `_popcnt32` - the signededness of the argument and return were flipped * `_popcnt64` - the signededness of the argument was flipped and the argument was too large bit-wise * `_mm_tzcnt_32` - the return value's sign was flipped * `_mm_tzcnt_64` - the return value's sign was flipped * A good number of intrinsics used `imm8: i8` or `imm8: u8` instead of `imm8: i32` which Intel was using. (we were also internally inconsistent) * A number of intrinsics working with `__m64` were instead working with i64/u64, so they're now corrected to operate with the vector types instead. Currently the verifications performed are: * Each name in Rust is defined in the XML document * The arguments/return values all agree. * The CPUID features listed in the XML document are all enabled in Rust as well. The type matching right now is pretty loose and has a lot of questionable changes. Future commits will touch these up to be more strict and require closer adherence with Intel's own types. Otherwise types like `i32x8` (or any integers with 256 bits) all match up to `__m256i` right now, althoguh this may want to change in the future. Finally we're also not testing the instruction listed in the XML right now. There's a huge number of discrepancies between the instruction listed in the XML and the instruction listed in `assert_instr`, and those'll need to be taken care of in a future commit. Closes #240
stdsimd
Experimental support for SIMD destined to eventually become part of Rust's standard library
This is a work in progress.
- Documentation - i686
- Documentation - x86_64
- Documentation - arm
- Documentation - aarch64
- How to get started
- How to help implement intrinsics
Approach
The main goal is to expose APIs defined by vendors with the least amount of
abstraction possible. On x86, for example, the API should correspond to that
provided by emmintrin.h.
License
stdsimd is primarily distributed under the terms of both the MIT license and
the Apache License (Version 2.0), with portions covered by various BSD-like
licenses.
See LICENSE-APACHE, and LICENSE-MIT for details.