This commit:
* renames `coresimd` to `core_arch` and `stdsimd` to `std_detect`
* `std_detect` does no longer depend on `core_arch` - it is a freestanding
`no_std` library that only depends on `core` - it is renamed to `std_detect`
* moves the top-level coresimd and stdsimd directories into the appropriate
crates/... directories - this simplifies creating crate.io releases of these crates
* moves the top-level `coresimd` and `stdsimd` sub-directories into their
corresponding crates in `crates/{core_arch, std_detect}`.
This commit implements automatic verification of implement ARM/AArch64
intrinsics. Or it's at least a start! This downloads a snapshot of ARM's
[online documentation][docs] and implements necessary logic to parse
that and use it to verify all the intrinsics. Almost everything
checked out A-OK but a few minor tweaks were needed to the neon
intrinsics and the crc ones needed some renaming.
[docs]: https://developer.arm.com/technologies/neon/intrinsics
With RFC 2325 looking close to being accepted, I took a crack at
reorganizing this repository to being more amenable for inclusion in
libstd/libcore. My current plan is to add stdsimd as a submodule in
rust-lang/rust and then use `#[path]` to include the modules directly
into libstd/libcore.
Before this commit, however, the source code of coresimd/stdsimd
themselves were not quite ready for this. Imports wouldn't compile for
one reason or another, and the organization was also different than the
RFC itself!
In addition to moving a lot of files around, this commit has the
following major changes:
* The `cfg_feature_enabled!` macro is now renamed to
`is_target_feature_detected!`
* The `vendor` module is now called `arch`.
* Under the `arch` module is a suite of modules like `x86`, `x86_64`,
etc. One per `cfg!(target_arch)`.
* The `is_target_feature_detected!` macro was removed from coresimd.
Unfortunately libcore has no ability to export unstable macros, so for
now all feature detection is canonicalized in stdsimd.
The `coresimd` and `stdsimd` crates have been updated to the planned
organization in RFC 2325 as well. The runtime bits saw the largest
amount of refactoring, seeing a good deal of simplification without the
core/std split.
