Co-Authored-By: lzutao <taolzu@gmail.com>

Value was renamed to Operand in rust-lang@ad2de8b
ScalarPair to Slice in rust-lang@fe50b4e

Not familiar enough with rustc's source to know if the comment is even still applicable.

These are types that get memcpy'd a lot.

The reduction in `memcpy` calls greatly outweighs the cost of the extra
allocations, for a net performance win.

The reduction in `memcpy` calls outweighs the cost of the extra
allocations, for a net performance win.

use randSecure and randABytes

Sync with rust-lang/rust master branch

It's a large type -- 176 bytes on 64-bit. And it's passed around and
returned from a lot of functions, including within PResult.

This commit boxes it, which reduces memory traffic. In particular,
`PResult` shrinks to 16 bytes in the best case; this reduces instruction
counts by up to 2% on various workloads.

declare EnvKey before use to fix build error

This function is very hot, doesn't get inlined because it's recursive,
and the function calls are significant.

This commit splits it into inlined and uninlined variants, and uses the
inlined variant for the hot call site. This wins several percent on a
few benchmarks.

Co-Authored-By: Robin Kruppe <robin.kruppe@gmail.com>

…es are.

Fix rust-lang#63479.

…ust-lang#63479.

…ment names.

Co-Authored-By: Mazdak Farrokhzad <twingoow@gmail.com>

…alls, r=rkruppe

Added table containing the system calls used by Instant and SystemTime.

# Description
See rust-lang#32626 for a discussion on documenting system calls used by Instant and SystemTime.

## Changes
- Added a table containing the system calls used by each platform.

EDIT: If I can format this table better (due to the large links) please let me know.
I'd also be happy to learn a quick command to generate the docs on my host machine! Currently I am using: `python x.py doc --stage 0 src/libstd` but that gives me some `unrecognized intrinsic` errors. Advice is always welcome :)

closes rust-lang#32626

Fix minor typo in docs.

This comment is prolly refering to the comment in [const_eval_raw_provider](https://github.com/rust-lang/rust/pull/64116/files#diff-e0b58bb6712edaa8595ad7237542c958R616), not itself.

A few cosmetic improvements to code & comments in liballoc and libcore

Factored out from hacking on rustc for work on the REPL.

r? @Centril

…ode, r=zackmdavis

Shrink `ObligationCauseCode`

These commits reduce the size of `ObligationCauseCode` from 56 bytes to 32 bytes on 64-bit. This reduces instruction counts on various benchmarks by up to 1%, due to less `memcpy`ing.

use randSecure and randABytes

r? @alexcrichton

cc @n-salim

…r=zackmdavis

Box `DiagnosticBuilder`.

It's a large type -- 176 bytes on 64-bit. And it's passed around and
returned from a lot of functions, including within `PResult`.

This commit boxes it, which reduces memory traffic. In particular,
`PResult` shrinks to 16 bytes in the best case; this reduces instruction
counts by up to 2% on various workloads. The commit touches a lot of
lines but it's almost all trivial plumbing changes.

Fast path for vec.clear/truncate

For trivial types like `u8`, `vec.truncate()`/`vec.clear()` relies on the optimizer to remove the loop. This means more work in debug builds, and more work for the optimizer.

Avoiding this busywork is exactly what `mem::needs_drop::<T>()` is for.

Fix inconsistent link formatting.

Trim rustc-workspace-hack

Those dependencies seem no longer necessary.
`./x.py test` and `x86_64-gnu-tools` container passed locally so I think this won't hurt.

…xcrichton

 declare EnvKey before use to fix build error

r? @alexcrichton

…as_waiting_from, r=Mark-Simulacrum

Inline `mark_neighbours_as_waiting_from`.

This function is very hot, doesn't get inlined because it's recursive,
and the function calls are significant.

This commit splits it into inlined and uninlined variants, and uses the
inlined variant for the hot call site. This wins several percent on a
few benchmarks.

r? @nikomatsakis

…gify, r=Mark-Simulacrum

Remove raw string literal quotes from error index descriptions

The error index has unnecessary `r##"` and `"##` around the descriptions from rust-lang#63721. Removing the `stringify` call removes them.

r? @Mark-Simulacrum

Add self to .mailmap

typo fix

…tural-match, r=varkor

fn ptr is structural match

Make fn ptr always structural match, regardless of whether the formal parameter types or return type are.

Fix rust-lang#63479.

codegen: use "_N" (like for other locals) instead of "argN", for argument names.

Based on rust-lang#64408 (second commit is new), fixing something I mentioned in rust-lang#64408 (which turned to be an immediate blocker for unifying relevant codepaths).

Closes rust-lang#64408 (by containing it).

r? @rkruppe

fix rust-lang#64430, confusing `owned_box` error message in no_std build

Fixes rust-lang#64430