std: Add `arch` and `simd` modules
This commit imports the `stdsimd` crate into the standard library,
creating an `arch` and `simd` module inside of both libcore and libstd.
Both of these modules are **unstable** and will continue to be so until
RFC 2335 is stabilized.
As a brief recap, the modules are organized as so:
* `arch` contains all current architectures with intrinsics, for example
`std::arch::x86`, `std::arch::x86_64`, `std::arch::arm`, etc. These
modules contain all of the intrinsics defined for the platform, like
`_mm_set1_epi8`.
* In the standard library, the `arch` module also exports a
`is_target_feature_detected` macro which performs runtime detection to
determine whether a target feature is available at runtime.
* The `simd` module contains experimental versions of strongly-typed
lane-aware SIMD primitives, to be fully fleshed out in a future RFC.
The main purpose of this commit is to start pulling in all these
intrinsics and such into the standard library on nightly and allow
testing and such. This'll help allow users to easily kick the tires and
see if intrinsics work as well as allow us to test out all the
infrastructure for moving the intrinsics into the standard library.
Don't produce TOCs for doc markdown files
Currently, we are producing headers for markdown files,
which is generally not what we want. As such, passing this
flag causes them to render normally.
https://doc.rust-lang.org/nightly/book/ is an example page currently where this is done incorrectly.
Backport LLVM fixes for a JumpThreading / assume intrinsic bug
This fixes the original cause of #48116 and restores the assume intrinsic that was removed as a workaround.
r? @alexcrichton
FusedIterator is a marker trait that promises that the implementing
iterator continues to return `None` from `.next()` once it has returned
`None` once (and/or `.next_back()`, if implemented).
The effects of FusedIterator are already widely available through
`.fuse()`, but with stable `FusedIterator`, stable Rust users can
implement this trait for their iterators when appropriate.
Restore the download of rust-mingw
The build might otherwise break due to mixing MinGW object files from rust-std and the local MinGW which might be newer/older than the version used to build rust-std.
Fixes#48272
r? @alexcrichton
Improve --help performance for x.py
Since compiling the bootstrap command doesn't require any submodules,
we can skip updating submodules when a --help command is passed in.
On my machine, this saves 1 minute if the submodules are already
downloaded, and 10 minutes if run on a clean repo.
This commit also adds a message before compiling/downloading anything
when a --help command is passed in, to tell the user WHY --help
takes so long to complete. It also points the user to the bootstrap
README.md for faster help.
Finally, this fixes one warning message that still referenced using
make instead of x.py, even though x.py is now the standard way of
building rust.
Closes#37305
Disable NEON on musl ARMv7
`armv7-unknown-linux-musleabihf` target diverged a bit from `armv7-unknown-linux-gnueabihf` target. This PR re-syncs them.
Fix#47765.
add readme for librustdoc
In the same vein as the other compiler-library readmes, here's one for rustdoc! It's mainly a "how does rustdoc even" blog-post-style writeup, but i wanted to have something in-repo so people could get a sense of what bits did what.
Revert "correct subtle bug in the type variable code"
This reverts commit ccd92c2a4e.
This commit is the source of a major perf regression, and was not
intended to be included in #47861. At some point I must have
accidentally re-added the commit.
Fixes#48660.
r? @nikomatsakis
Replace Rc with Lrc for shared data
This replaces `Rc`s reachable from `TyCtxt` with `Lrc`. This has no effect unless `cfg(parallel_queries)` is set. It also contains a fix for the `Decodable` impl for `Arc`.
r? @nikomatsakis
This commit imports the `stdsimd` crate into the standard library,
creating an `arch` and `simd` module inside of both libcore and libstd.
Both of these modules are **unstable** and will continue to be so until
RFC 2335 is stabilized.
As a brief recap, the modules are organized as so:
* `arch` contains all current architectures with intrinsics, for example
`std::arch::x86`, `std::arch::x86_64`, `std::arch::arm`, etc. These
modules contain all of the intrinsics defined for the platform, like
`_mm_set1_epi8`.
* In the standard library, the `arch` module also exports a
`is_target_feature_detected` macro which performs runtime detection to
determine whether a target feature is available at runtime.
* The `simd` module contains experimental versions of strongly-typed
lane-aware SIMD primitives, to be fully fleshed out in a future RFC.
The main purpose of this commit is to start pulling in all these
intrinsics and such into the standard library on nightly and allow
testing and such. This'll help allow users to easily kick the tires and
see if intrinsics work as well as allow us to test out all the
infrastructure for moving the intrinsics into the standard library.
Currently, we are producing headers for markdown files,
which is generally not what we want. As such, passing this
flag causes them to render normally.
These arguments are passed to the relevant x.py invocation in all cases
anyway. As such, there is no need to separately configure them. x.py
will ignore the configuration when they are passed on the command line
anyway.
This reverts commit ccd92c2a4e.
This commit is the source of a major perf regression, and was not
intended to be included in #47861. At some point I must have
accidentally re-added the commit.
It was an existing solution to tell the user why a --help command
takes a long time to process. However, it would only print if the
stage0 rust compiler needed to be downloaded, it came after
update_submodules (which took a long time), and it was immediately
followed by download messages and loading bars, meaning users could
easily gloss over the message.
This commit also moves the help message out of main(), and instead
puts it at the top of bootstrap(). main() is intended to be minimal,
only handling error messages.
