prep work for using timely dataflow with NLL
Two major changes:
**Two-phase borrows are overhauled.** We no longer have two bits per borrow. Instead, we track -- for each borrow -- an (optional) "activation point". Then, for each point P where the borrow is in scope, we check where P falls relative to the activation point. If P is between the reservation point and the activation point, then this is the "reservation" phase of the borrow, else the borrow is considered active. This is simpler and means that the dataflow doesn't have to care about 2-phase at all, at last not yet.
**We no longer support using the MIR borrow checker without NLL.** It is going to be increasingly untenable to support lexical mode as we go forward, I think, and also of increasingly little value. This also exposed a few bugs in NLL mode due to increased testing.
r? @pnkfelix
cc @bobtwinkles
Implement Chalk lowering rule Normalize-From-Impl
This extends the Chalk lowering pass with the "Normalize-From-Impl" rule for generating program clauses from a trait definition as part of #49177.
r? @nikomatsakis
Previously, we were emittinng analysis data for all tasks, including `doc`. That meant we got two sets of save-analysis data, one from the normal build and one from the docs. That means indexing with the RLS took twice as long and made downloads larger and build times longer.
cc https://github.com/rust-lang-nursery/rls/issues/826
Stabilize x86/x86_64 SIMD
This commit stabilizes the SIMD in Rust for the x86/x86_64 platforms. Notably
this commit is stabilizing:
* The `std::arch::{x86, x86_64}` modules and the intrinsics contained inside.
* The `is_x86_feature_detected!` macro in the standard library
* The `#[target_feature(enable = "...")]` attribute
* The `#[cfg(target_feature = "...")]` matcher
Stabilization of the module and intrinsics were primarily done in
rust-lang-nursery/stdsimd#414 and the two attribute stabilizations are done in
this commit. The standard library is also tweaked a bit with the new way that
stdsimd is integrated.
Note that other architectures like `std::arch::arm` are not stabilized as part
of this commit, they will likely stabilize in the future after they've been
implemented and fleshed out. Similarly the `std::simd` module is also not being
stabilized in this commit, only `std::arch`. Finally, nothing related to `__m64`
is stabilized in this commit either (MMX), only SSE and up types and intrinsics
are stabilized.
Closes#29717Closes#44839Closes#48556
`String::replace_range` was previously called `String::splice`, so this
note was necessary to differentiate it from the `Vec` method. Now that
it's renamed, this note no longer seems necessary.
std: Minimize size of panicking on wasm
This commit applies a few code size optimizations for the wasm target to
the standard library, namely around panics. We notably know that in most
configurations it's impossible for us to print anything in
wasm32-unknown-unknown so we can skip larger portions of panicking that
are otherwise simply informative. This allows us to get quite a nice
size reduction.
Finally we can also tweak where the allocation happens for the
`Box<Any>` that we panic with. By only allocating once unwinding starts
we can reduce the size of a panicking wasm module from 44k to 350 bytes.
Rollup of 8 pull requests
Successful merges:
- #49555 (Inline most of the code paths for conversions with boxed slices)
- #49606 (Prevent broken pipes causing ICEs)
- #49646 (Use box syntax instead of Box::new in Mutex::remutex on Windows)
- #49647 (Remove `underscore_lifetimes` and `match_default_bindings` from active feature list)
- #49931 (Fix incorrect span in `&mut` suggestion)
- #49959 (rustbuild: allow building tools with debuginfo)
- #49965 (Remove warning about f64->f32 cast being potential UB)
- #49994 (Remove unnecessary indentation in rustdoc book codeblock.)
Failed merges:
Remove warning about f64->f32 cast being potential UB
As discussed in #15536, the LLVM documentation incorrect described overflowing f64->f32 casts as being undefined behavior. LLVM never treated them as such, and the documentation has been adjusted in https://reviews.llvm.org/rL329065. As such, this warning can now be removed.
Closes#49622.
---
I could not find any existing test checking for this warning. Should I be adding a test for the absence of the warning instead?
rustbuild: allow building tools with debuginfo
Debugging information for the extended tools is currently disabled for
concerns about the size. This patch adds `--enable-debuginfo-tools` to
let one opt into having that debuginfo.
This is useful for debugging the tools in distro packages. We always
strip debuginfo into separate packages anyway, so the extra size is not
a concern in regular use.
Use box syntax instead of Box::new in Mutex::remutex on Windows
The Box::new(mem::uninitialized()) pattern actually actively copies
uninitialized bytes from the stack into the box, which is a waste of
time. Using the box syntax instead avoids the useless copy.
Prevent broken pipes causing ICEs
As the private `std::io::print_to` panics if there is an I/O error, which is used by `println!`, the compiler would ICE if one attempted to use a broken pipe (e.g. `rustc --help | false`). This introduces a new (private) macro `try_println!` which allows us to avoid this.
As a side note, it seems this macro might be useful publicly (and actually there seems to be [a crate specifically for this purpose](https://crates.io/crates/try_print/)), though that can probably be left for a future discussion.
One slight alternative approach would be to simply early exit without an error (i.e. exit code `0`), which [this comment](https://github.com/rust-lang/rust/issues/34376#issuecomment-377822526) suggests is the usual approach. I've opted not to take that approach initially, because I think it's more helpful to know when there is a broken pipe.
Fixes#34376.
Inline most of the code paths for conversions with boxed slices
This helps with the specific problem described in #49541, obviously without making any large change to how inlining works in the general case.
Everything involved in the conversions is made `#[inline]`, except for the `<Vec<T>>::into_boxed_slice` entry point which is made `#[inline(always)]` after checking that duplicating the function mentioned in the issue prevented its inlining if I only annotate it with
`#[inline]`.
For the record, that function was:
```rust
pub fn foo() -> Box<[u8]> {
vec![0].into_boxed_slice()
}
```
To help the inliner's job, we also hoist a `self.capacity() != self.len` check in `<Vec<T>>::shrink_to_fit` and mark it as `#[inline]` too.
Move Range*::contains to a single default impl on RangeBounds
Per the ongoing discussion in #32311.
This is my first PR to Rust (woo!), so I don't know if this requires an amendment to the original range_contains RFC, or not, or if we can just do a psuedo-RFC here. While this may no longer follow the explicit decision made in that RFC, I believe this better follows its spirit by adding the new contains method to all Ranges. It also allows users to be generic over all ranges and use this method without writing it themselves (my personal desired use case).
This also somewhat answers the unanswered question about Wrapping ranges in the above issue by instead just punting it to the question of what those types should return for start() & end(), or if they should implement RangeArgument at all. Those types could also implement their own contains method without implementing this trait, in which case the question remains the same.
This does add a new contains method to types that already implemented RangeArgument but not contains. These types are RangeFull, (Bound<T>, Bound<T>), (Bound<&'a T>, Bound<&'a T>). No tests have been added for these types yet. No inherent method has been added either.
r? @alexcrichton
This commit stabilizes the SIMD in Rust for the x86/x86_64 platforms. Notably
this commit is stabilizing:
* The `std::arch::{x86, x86_64}` modules and the intrinsics contained inside.
* The `is_x86_feature_detected!` macro in the standard library
* The `#[target_feature(enable = "...")]` attribute
* The `#[cfg(target_feature = "...")]` matcher
Stabilization of the module and intrinsics were primarily done in
rust-lang-nursery/stdsimd#414 and the two attribute stabilizations are done in
this commit. The standard library is also tweaked a bit with the new way that
stdsimd is integrated.
Note that other architectures like `std::arch::arm` are not stabilized as part
of this commit, they will likely stabilize in the future after they've been
implemented and fleshed out. Similarly the `std::simd` module is also not being
stabilized in this commit, only `std::arch`. Finally, nothing related to `__m64`
is stabilized in this commit either (MMX), only SSE and up types and intrinsics
are stabilized.
Closes#29717Closes#44839Closes#48556
