On architectures such as powerpc64 that use extend_integer_width_to in
their C ABI processing, integer parameters shorter than the native
register width will be annotated with the ArgAttribute::SExt or
ArgAttribute::ZExt attribute, and that attribute will be included in the
generated LLVM IR.

In this test, all relevant parameters are `i32`, which will get the
`signext` annotation on the relevant 64-bit architectures. Match both
the annotated and non-annotated case, but enforce that the annotation is
applied consistently.

This commit changes the HIR lowering around `await` so that temporary
lifetimes are extended. Previously, await was lowered as:

```rust
{
    let mut pinned = future;
    loop {
        match ::std::future::poll_with_tls_context(unsafe {
            <::std::pin::Pin>::new_unchecked(&mut pinned)
        }) {
            ::std::task::Poll::Ready(result) => break result,
            ::std::task::Poll::Pending => {}
        }
        yield ();
    }
}
```

With this commit, await is lowered as:

```rust
match future {
    mut pinned => loop {
        match ::std::future::poll_with_tls_context(unsafe {
            <::std::pin::Pin>::new_unchecked(&mut pinned)
        }) {
            ::std::task::Poll::Ready(result) => break result,
            ::std::task::Poll::Pending => {}
        }
        yield ();
    }
}
```

However, this change has the following side-effects:

- All temporaries in future will be considered to live across a
  yield for the purpose of auto-traits.
- Borrowed temporaries in future are likely to be considered to be live
  across the yield for the purpose of the generator transform.

Signed-off-by: David Wood <david@davidtw.co>

…onstantly.

Make `abs`, `wrapping_abs`, `overflowing_abs` const functions

This makes `abs`, `wrapping_abs` and `overflowing_abs` const functions like rust-lang#58044 makes `wrapping_neg` and `overflowing_neg` const functions.

`abs` is made const by returning `(self ^ -1) - -1` = `!self + 1` = `-self` for negative numbers and `(self ^ 0) - 0` = `self` for non-negative numbers. The subexpression `self >> ($BITS - 1)` evaluates to `-1` for negative numbers and `0` otherwise. The subtraction overflows when `self` is `min_value()`, as we would be subtracting `max_value() - -1`; this is when `abs` should overflow.

`wrapping_abs` and `overflowing_abs` make use of `wrapping_sub` and `overflowing_sub` instead of the subtraction operator.

Add Yaah to clippy toolstain notification list

…xcrichton

test/c-variadic: Fix patterns on powerpc64

On architectures such as powerpc64 that use extend_integer_width_to in
their C ABI processing, integer parameters shorter than the native
register width will be annotated with the ArgAttribute::SExt or
ArgAttribute::ZExt attribute, and that attribute will be included in the
generated LLVM IR.

In this test, all relevant parameters are `i32`, which will get the
`signext` annotation on the relevant 64-bit architectures. Match both
the annotated and non-annotated case, but enforce that the annotation is
applied consistently.

…ry-lifetimes, r=matthewjasper

lowering: extend temporary lifetimes around await

Fixes rust-lang#63832.

r? @matthewjasper
cc @nikomatsakis

lldb: avoid mixing "Hit breakpoint" message with other output.

This is to get `src/test/debuginfo/lexical-scopes-in-block-expression.rs` working.
It used to work like a week ago, and the main change that happened was I switched from Python 2 to Python 3 (I don't remember why, but I did get rid of the build dir entirely, and it fixed something else).

The error was:
```
error: line not found in debugger output: [...]$27 = 10
```

Relevant part of the output:
```
print val
(long) $26 = 15
print ten
(long) $27 = 10 Hit breakpoint 15.1: where = a`lexical_scopes_in_block_expression::main::hcdd5c3caa9166e73 + 1223 at lexical-scopes-in-block-expression.rs:504:4, address = 0x00005555555556e7, resolved, hit count = 1
Hit breakpoint 16.1: where = a`lexical_scopes_in_block_expression::main::hcdd5c3caa9166e73 + 631 at lexical-scopes-in-block-expression.rs:510:8, address = 0x0000555555555497, resolved, hit count = 1
```

There are most `print` commands and their outputs before, and more `Hit breakpoint` messages afterwards, so I assume what happens is the `Hit breakpoint` messages should be interleaved but somehow they ended up being buffered after all of the other output.

As a stopgap measure I'm adding a newline before each `Hit breakpoint` so they don't end up on the same line as the last `print` output (which breaks our pattern-matching).

r? @michaelwoerister

…illaumeGomez

Clarify E0507 to note Fn/FnMut relationship to borrowing

Fixes rust-lang#37904.

Changed instant is earlier to instant is later

Fixed the documentation issue from rust-lang#64322

…kernel, r=oli-obk

rustc_mir: buffer -Zdump-mir output instead of pestering the kernel constantly.

This brings `mir-opt` tests from `197s` (over 3 minutes!) to `2.85s`, on my build server.
That's a nice speedup of about `69x` and so it definitely fixes rust-lang#58485, for me.

It's such a beginner mistake I feel like maybe `clippy` should lint against it?
(cc @Manishearth @oli-obk)