Commit Graph

133258 Commits

Author SHA1 Message Date
bors
603ab5bd6e Auto merge of #79064 - ehuss:rustbook-logs, r=Mark-Simulacrum
Fix displaying errors when rustbook tests fail.

This ensures that output from mdbook is displayed when running the rustbook wrapper. I believe this was a regression as a result of #69115 where it was changed from running `rustdoc` directly to using rustbook.
2020-11-15 15:39:58 +00:00
bors
5fab31e5dd Auto merge of #79070 - jonas-schievink:rollup-wacn2b8, r=jonas-schievink
Rollup of 13 pull requests

Successful merges:

 - #77802 (Allow making `RUSTC_BOOTSTRAP` conditional on the crate name)
 - #79004 (Add `--color` support to bootstrap)
 - #79005 (cleanup: Remove `ParseSess::injected_crate_name`)
 - #79016 (Make `_` an expression, to discard values in destructuring assignments)
 - #79019 (astconv: extract closures into a separate trait)
 - #79026 (Implement BTreeMap::retain and BTreeSet::retain)
 - #79031 (Validate that locals have a corresponding `LocalDecl`)
 - #79034 (rustc_resolve: Make `macro_rules` scope chain compression lazy)
 - #79036 (Move Steal to rustc_data_structures.)
 - #79041 (Rename clean::{ItemEnum -> ItemKind}, clean::Item::{inner -> kind})
 - #79058 (Move likely/unlikely argument outside of invisible unsafe block)
 - #79059 (Print 'checking cranelift artifacts' to easily separate it from other artifacts)
 - #79063 (Update rustfmt to v1.4.26)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
2020-11-15 13:19:05 +00:00
Jonas Schievink
568354f01f
Rollup merge of #79063 - calebcartwright:update-rustfmt, r=Mark-Simulacrum
Update rustfmt to v1.4.26
2020-11-15 13:40:07 +01:00
Jonas Schievink
c8ac745040
Rollup merge of #79059 - jyn514:cranelift, r=Mark-Simulacrum
Print 'checking cranelift artifacts' to easily separate it from other artifacts

Before:

```
Checking rustdoc artifacts (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-gnu)
    Checking rustdoc v0.0.0 (/home/joshua/rustc/src/librustdoc)
    Checking rustdoc-tool v0.0.0 (/home/joshua/rustc/src/tools/rustdoc)
    Finished release [optimized] target(s) in 2.08s
    Checking regalloc v0.0.31
    Checking gimli v0.22.0
    Checking object v0.21.1
    Checking cranelift-codegen v0.67.0 (https://github.com/bytecodealliance/wasmtime/?branch=main#44cbdece)
    Checking cranelift-module v0.67.0 (https://github.com/bytecodealliance/wasmtime/?branch=main#44cbdece)
    Checking cranelift-native v0.67.0 (https://github.com/bytecodealliance/wasmtime/?branch=main#44cbdece)
    Checking cranelift-frontend v0.67.0 (https://github.com/bytecodealliance/wasmtime/?branch=main#44cbdece)
    Checking cranelift-object v0.67.0 (https://github.com/bytecodealliance/wasmtime/?branch=main#44cbdece)
    Checking cranelift-simplejit v0.67.0 (https://github.com/bytecodealliance/wasmtime/?branch=main#44cbdece)
    Checking rustc_codegen_cranelift v0.1.0 (/home/joshua/rustc/compiler/rustc_codegen_cranelift)
    Finished release [optimized] target(s) in 10.55s

```

After:

```
Checking rustdoc artifacts (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-gnu)
    Checking rustdoc v0.0.0 (/home/joshua/rustc/src/librustdoc)
    Checking rustdoc-tool v0.0.0 (/home/joshua/rustc/src/tools/rustdoc)
    Finished release [optimized] target(s) in 2.08s
Checking cranelift artifacts (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-gnu)
    Checking cranelift-codegen v0.67.0 (https://github.com/bytecodealliance/wasmtime/?branch=main#44cbdece)
```

r? `@bjorn3`
`@bors` delegate=bjorn3
2020-11-15 13:40:05 +01:00
Jonas Schievink
ae1916b3b4
Rollup merge of #79058 - dtolnay:likelymacro, r=Mark-Simulacrum
Move likely/unlikely argument outside of invisible unsafe block

The previous `likely!`/`unlikely!` macros were unsound because it permits the caller's expr to contain arbitrary unsafe code.

```rust
pub fn huh() -> bool {
    likely!(std::ptr::read(&() as *const () as *const bool))
}
```

**Before:** compiles cleanly.
**After:**

```console
error[E0133]: call to unsafe function is unsafe and requires unsafe function or block
   |
70 |     likely!(std::ptr::read(&() as *const () as *const bool))
   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ call to unsafe function
   |
   = note: consult the function's documentation for information on how to avoid undefined behavior
```
2020-11-15 13:40:03 +01:00
Jonas Schievink
bc9ef6cf72
Rollup merge of #79041 - jyn514:inner-to-kind, r=petrochenkov
Rename clean::{ItemEnum -> ItemKind}, clean::Item::{inner -> kind}

r? ````@petrochenkov````
cc ````@GuillaumeGomez````

Follow-up to https://github.com/rust-lang/rust/pull/77820#discussion_r502931757.
2020-11-15 13:40:01 +01:00
Jonas Schievink
ce775bc4f6
Rollup merge of #79036 - cjgillot:steal, r=oli-obk
Move Steal to rustc_data_structures.
2020-11-15 13:39:59 +01:00
Jonas Schievink
b0178f4cc7
Rollup merge of #79034 - petrochenkov:mrscopes3, r=eddyb
rustc_resolve: Make `macro_rules` scope chain compression lazy

As suggested in https://github.com/rust-lang/rust/pull/78826#issuecomment-723420664.
2020-11-15 13:39:57 +01:00
Jonas Schievink
9c6d3c0940
Rollup merge of #79031 - camelid:mir-validate-local-decl, r=jonas-schievink
Validate that locals have a corresponding `LocalDecl`

Fixes #73356.
2020-11-15 13:39:56 +01:00
Jonas Schievink
aa685e2024
Rollup merge of #79026 - mbrubeck:btree_retain, r=m-ou-se
Implement BTreeMap::retain and BTreeSet::retain

Adds new methods `BTreeMap::retain` and `BTreeSet::retain`.  These are implemented on top of `drain_filter` (#70530).

The API of these methods is identical to `HashMap::retain` and `HashSet::retain`, which were implemented in #39560 and stabilized in #36648.  The docs and tests are also copied from HashMap/HashSet.

The new methods are unstable, behind the `btree_retain` feature gate, with tracking issue #79025.  See also rust-lang/rfcs#1338.
2020-11-15 13:39:54 +01:00
Jonas Schievink
00396cb23a
Rollup merge of #79019 - lcnr:generic-arg-validation, r=petrochenkov
astconv: extract closures into a separate trait

Am currently looking into completely removing `check_generic_arg_count` and `create_substs_for_generic_args` was somewhat difficult to understand for me so I moved these closures into a trait.

This should not have changed the behavior of any of these methods
2020-11-15 13:39:50 +01:00
Jonas Schievink
f66af28641
Rollup merge of #79016 - fanzier:underscore-expressions, r=petrochenkov
Make `_` an expression, to discard values in destructuring assignments

This is the third and final step towards implementing destructuring assignment (RFC: rust-lang/rfcs#2909, tracking issue: #71126). This PR is the third and final part of #71156, which was split up to allow for easier review.

With this PR, an underscore `_` is parsed as an expression but is allowed *only* on the left-hand side of a destructuring assignment. There it simply discards a value, similarly to the wildcard `_` in patterns. For instance,
```rust
(a, _) = (1, 2)
```
will simply assign 1 to `a` and discard the 2. Note that for consistency,
```
_ = foo
```
is also allowed and equivalent to just `foo`.

Thanks to ````@varkor```` who helped with the implementation, particularly around pre-expansion gating.

r? ````@petrochenkov````
2020-11-15 13:39:48 +01:00
Jonas Schievink
f32191f78f
Rollup merge of #79005 - petrochenkov:noinjected, r=davidtwco
cleanup: Remove `ParseSess::injected_crate_name`

Its only remaining use is in pretty-printing where the necessary information can be easily re-computed.
2020-11-15 13:39:46 +01:00
Jonas Schievink
e0c378a673
Rollup merge of #79004 - jyn514:bacon, r=Mark-Simulacrum
Add `--color` support to bootstrap

When running under external utilities which wrap x.py, it can be convenient to force color support on.
2020-11-15 13:39:45 +01:00
Jonas Schievink
8825942e86
Rollup merge of #77802 - jyn514:bootstrap-specific, r=nikomatsakis
Allow making `RUSTC_BOOTSTRAP` conditional on the crate name

Motivation: This came up in the [Zulip stream](https://rust-lang.zulipchat.com/#narrow/stream/233931-t-compiler.2Fmajor-changes/topic/Require.20users.20to.20confirm.20they.20know.20RUSTC_.E2.80.A6.20compiler-team.23350/near/208403962) for https://github.com/rust-lang/compiler-team/issues/350.
See also https://github.com/rust-lang/cargo/pull/6608#issuecomment-458546258; this implements https://github.com/rust-lang/cargo/issues/6627.
The goal is for this to eventually allow prohibiting setting `RUSTC_BOOTSTRAP` in build.rs (https://github.com/rust-lang/cargo/issues/7088).

## User-facing changes

- `RUSTC_BOOTSTRAP=1` still works; there is no current plan to remove this.
- Things like `RUSTC_BOOTSTRAP=0` no longer activate nightly features. In practice this shouldn't be a big deal, since `RUSTC_BOOTSTRAP` is the opposite of stable and everyone uses `RUSTC_BOOTSTRAP=1` anyway.
- `RUSTC_BOOTSTRAP=x` will enable nightly features only for crate `x`.
- `RUSTC_BOOTSTRAP=x,y` will enable nightly features only for crates `x` and `y`.

## Implementation changes

The main change is that `UnstableOptions::from_environment` now requires
an (optional) crate name. If the crate name is unknown (`None`), then the new feature is not available and you still have to use `RUSTC_BOOTSTRAP=1`. In practice this means the feature is only available for `--crate-name`, not for `#![crate_name]`; I'm interested in supporting the second but I'm not sure how.

Other major changes:

- Added `Session::is_nightly_build()`, which uses the `crate_name` of
the session
- Added `nightly_options::match_is_nightly_build`, a convenience method
for looking up `--crate-name` from CLI arguments.
`Session::is_nightly_build()`should be preferred where possible, since
it will take into account `#![crate_name]` (I think).
- Added `unstable_features` to `rustdoc::RenderOptions`

I'm not sure whether this counts as T-compiler or T-lang; _technically_ RUSTC_BOOTSTRAP is an implementation detail, but it's been used so much it seems like this counts as a language change too.

r? `@joshtriplett`
cc `@Mark-Simulacrum` `@hsivonen`
2020-11-15 13:39:43 +01:00
bors
0468845924 Auto merge of #78472 - hermitcore:builtins, r=Mark-Simulacrum
add options to use optimized and mangled compiler builtins

In principle the compiler builtin features are also offered to alloc and std.
2020-11-15 10:37:11 +00:00
Stefan Lankes
6de51252e0
add options to use optimized and mangled compiler builtins 2020-11-15 08:23:31 +01:00
bors
75042566d1 Auto merge of #79065 - Dylan-DPC:rollup-gag1drk, r=Dylan-DPC
Rollup of 15 pull requests

Successful merges:

 - #78352 (Do not call `unwrap` with `signatures` option enabled)
 - #78590 (refactor: removing alloc::collections::vec_deque ignore-tidy-filelength)
 - #78848 (Bump minimal supported LLVM version to 9)
 - #78856 (Explicitly checking for or-pattern before test)
 - #78948 (test: add `()=()=()=...` to weird-exprs.rs)
 - #78962 (Add a test for r# identifiers)
 - #78963 (Added some unit tests as requested)
 - #78966 (Never inline C variadics, cold functions, functions with incompatible attributes ...)
 - #78968 (Include llvm-as in llvm-tools-preview component)
 - #78969 (Normalize function type during validation)
 - #78980 (Fix rustc_ast_pretty print_qpath resulting in invalid macro input)
 - #78986 (Avoid installing external LLVM dylibs)
 - #78988 (Fix an intrinsic invocation on threaded wasm)
 - #78993 (rustc_target: Fix dash vs underscore mismatches in option names)
 - #79013 (Clean up outdated `use_once_payload` pretty printer comment)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
2020-11-15 02:21:18 +00:00
Dylan DPC
96515ccc7a
Rollup merge of #79013 - jryans:cleanup-use-once-pretty-comment, r=Mark-Simulacrum
Clean up outdated `use_once_payload` pretty printer comment

While reading some parts of the pretty printer code, I noticed this old comment
which seemed out of place. The `use_once_payload` this outdated comment mentions
was removed in 2017 in 40f03a1e0d, so this
completes the work by removing the comment.
2020-11-15 03:03:01 +01:00
Dylan DPC
96fc0f4c2f
Rollup merge of #78993 - petrochenkov:specdash, r=oli-obk
rustc_target: Fix dash vs underscore mismatches in option names

Fixes https://github.com/rust-lang/rust/issues/78981 (regression from https://github.com/rust-lang/rust/pull/78875, the old option names used dashes)
2020-11-15 03:02:59 +01:00
Dylan DPC
d57212d49e
Rollup merge of #78988 - alexcrichton:one-more-intrinsic, r=sfackler
Fix an intrinsic invocation on threaded wasm

This looks like it was forgotten to get updated in #74482 and wasm with
threads isn't built on CI so we didn't catch this by accident.
2020-11-15 03:02:57 +01:00
Dylan DPC
e3d52b8051
Rollup merge of #78986 - Mark-Simulacrum:fix-llvm, r=alexcrichton
Avoid installing external LLVM dylibs

If the LLVM was externally provided, then we don't currently copy artifacts into
the sysroot. This is not necessarily the right choice (in particular, it will
require the LLVM dylib to be in the linker's load path at runtime), but the
common use case for external LLVMs is distribution provided LLVMs, and in that
case they're usually in the standard search path (e.g., /usr/lib) and copying
them here is going to cause problems as we may end up with the wrong files and
isn't what distributions want.

This behavior may be revisited in the future though.

Fixes #78932.
2020-11-15 03:02:55 +01:00
Dylan DPC
4fcb617cbe
Rollup merge of #78980 - thiolliere:gui-fix-qpath, r=estebank
Fix rustc_ast_pretty print_qpath resulting in invalid macro input

related https://github.com/rust-lang/rust/issues/76874 (third case)

### Issue:

The input for a procedural macro is incorrect, for the rust code:
```rust

mod m {
    pub trait Tr {
        type Ts: super::Tu;
    }
}

trait Tu {
    fn dummy() { }
}

#[may_proc_macro]
fn foo() {
    <T as m::Tr>::Ts::dummy();
}
```
the macro will get the input:
```rust
fn foo() {
    <T as m::Tr>::dummy();
}
```
Thus `Ts` has disappeared.

### Fix:

This is due to invalid pretty print of qpath. This PR fix it.
2020-11-15 03:02:53 +01:00
Dylan DPC
7e0441dc36
Rollup merge of #78969 - tmiasko:normalize, r=davidtwco
Normalize function type during validation

During inlining, the callee body is normalized and has types revealed,
but some of locals corresponding to the arguments might come from the
caller body which is not. As a result the caller body does not pass
validation without additional normalization.

Closes #78442.
2020-11-15 03:02:51 +01:00
Dylan DPC
3fe2abafe5
Rollup merge of #78968 - zec:add-llvm-as, r=Mark-Simulacrum
Include llvm-as in llvm-tools-preview component

Including `llvm-as` adds the ability to include assembly language fragments that can be inlined using LTO while making sure the correct version of LLVM is always used.
2020-11-15 03:02:49 +01:00
Dylan DPC
6be44ed3b5
Rollup merge of #78966 - tmiasko:inline-never, r=oli-obk
Never inline C variadics, cold functions, functions with incompatible attributes ...

... and fix generator inlining.

Closes #67863.
Closes #78859.
2020-11-15 03:02:48 +01:00
Dylan DPC
335a2554f9
Rollup merge of #78963 - richkadel:llvm-coverage-counters-2.0.4, r=tmandry
Added some unit tests as requested

As discussed in PR #78267, for example:

* https://github.com/rust-lang/rust/pull/78267#discussion_r515404722
* https://github.com/rust-lang/rust/pull/78267#discussion_r515405958

r? ```````@tmandry```````
FYI: ```````@wesleywiser```````

This is pretty much self contained, but depending on feedback and timing, I may have a chance to add a few more unit tests requested against `counters.rs`. I'm looking at those now.
2020-11-15 03:02:46 +01:00
Dylan DPC
50603891dc
Rollup merge of #78962 - poliorcetics:rustdoc-raw-ident-test, r=jyn514
Add a test for r# identifiers

I'm not entirely sure I properly ran the test locally (I think so though), waiting for CI to confirm. :)

```````@rustbot``````` modify labels: T-rustdoc

r? ```````@jyn514```````
2020-11-15 03:02:44 +01:00
Dylan DPC
7f7fa9786a
Rollup merge of #78948 - slanterns:master, r=varkor
test: add `()=()=()=...` to weird-exprs.rs

Idea from https://github.com/rust-lang/rust/pull/71156#discussion_r410953972 😄

Builds on nightly since https://github.com/rust-lang/rust/pull/78748 has been merged.
2020-11-15 03:02:42 +01:00
Dylan DPC
a29b68f326
Rollup merge of #78856 - mark-i-m:fix-or-pat-ice, r=matthewjasper
Explicitly checking for or-pattern before test

Fixes https://github.com/rust-lang/rust/issues/72680

cc https://github.com/rust-lang/rust/issues/54883

r? ````@varkor````
2020-11-15 03:02:40 +01:00
Dylan DPC
ae7020fcb4
Rollup merge of #78848 - DevJPM:ci-llvm-9, r=nikic
Bump minimal supported LLVM version to 9

This bumps the minimal tested llvm version to 9.
This should enable supporting newer LLVM features (and CPU extensions).

This was motived by #78361 having to drop features because of LLVM 8 not supporting certain CPU extensions yet.
This was declared relatively uncontroversial on [Zulip](https://rust-lang.zulipchat.com/#narrow/stream/182449-t-compiler.2Fhelp/topic/Min.20Supported.20LLVM.20Upgrade.20Process.3F/near/215957859).

Paging ````@eddyb```` because there was a comment in the [dockerfile](https://github.com/rust-lang/rust/blob/master/src/ci/docker/host-x86_64/x86_64-gnu-llvm-8/Dockerfile#L42) describing a hack (which I don't quite understand) which was also blocked by not having LLVM 9.
2020-11-15 03:02:39 +01:00
Dylan DPC
dbb37fb1ee
Rollup merge of #78590 - DeveloperC286:issue_60302, r=varkor
refactor: removing alloc::collections::vec_deque ignore-tidy-filelength

This PR removes the need for ignore-tidy-filelength for alloc::collections::vec_deque which is part of the issue https://github.com/rust-lang/rust/issues/60302

It is probably easiest to review this PR by looking at it commit by commit rather than looking at the overall diff.
2020-11-15 03:02:37 +01:00
Dylan DPC
dc4d65579c
Rollup merge of #78352 - JohnTitor:issue-75229, r=Dylan-DPC
Do not call `unwrap` with `signatures` option enabled

Fixes #75229
Didn't add a test since I couldn't set `RUST_SAVE_ANALYSIS_CONFIG` even with `rustc-env`.
2020-11-15 03:02:34 +01:00
Eric Huss
5b9e9d018f Fix displaying errors when rustbook tests fail. 2020-11-14 17:37:02 -08:00
Caleb Cartwright
a49848a607 Update rustfmt to v1.4.26 2020-11-14 18:47:34 -06:00
Joshua Nelson
6900dcbc03 Print 'checking cranelift artifacts' to easily separate it from other artifacts
Before:

```
Checking rustdoc artifacts (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-gnu)
    Checking rustdoc v0.0.0 (/home/joshua/rustc/src/librustdoc)
    Checking rustdoc-tool v0.0.0 (/home/joshua/rustc/src/tools/rustdoc)
    Finished release [optimized] target(s) in 2.08s
    Checking regalloc v0.0.31
    Checking gimli v0.22.0
    Checking object v0.21.1
    Checking cranelift-codegen v0.67.0 (https://github.com/bytecodealliance/wasmtime/?branch=main#44cbdece)
    Checking cranelift-module v0.67.0 (https://github.com/bytecodealliance/wasmtime/?branch=main#44cbdece)
    Checking cranelift-native v0.67.0 (https://github.com/bytecodealliance/wasmtime/?branch=main#44cbdece)
    Checking cranelift-frontend v0.67.0 (https://github.com/bytecodealliance/wasmtime/?branch=main#44cbdece)
    Checking cranelift-object v0.67.0 (https://github.com/bytecodealliance/wasmtime/?branch=main#44cbdece)
    Checking cranelift-simplejit v0.67.0 (https://github.com/bytecodealliance/wasmtime/?branch=main#44cbdece)
    Checking rustc_codegen_cranelift v0.1.0 (/home/joshua/rustc/compiler/rustc_codegen_cranelift)
    Finished release [optimized] target(s) in 10.55s

```

After:

```
Checking rustdoc artifacts (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-gnu)
    Checking rustdoc v0.0.0 (/home/joshua/rustc/src/librustdoc)
    Checking rustdoc-tool v0.0.0 (/home/joshua/rustc/src/tools/rustdoc)
    Finished release [optimized] target(s) in 2.08s
Checking cranelift artifacts (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-gnu)
    Checking cranelift-codegen v0.67.0 (https://github.com/bytecodealliance/wasmtime/?branch=main#44cbdece)
```
2020-11-14 17:37:37 -05:00
bors
361c4ea224 Auto merge of #79049 - tmiasko:lower-intrinsics, r=jonas-schievink
Lower intrinsics calls: forget, size_of, unreachable, wrapping_*

This allows constant propagation to evaluate `size_of` and `wrapping_*`,
and unreachable propagation to propagate a call to `unreachable`.

The lowering is performed as a MIR optimization, rather than during MIR
building to preserve the special status of intrinsics with respect to
unsafety checks and promotion.

Currently enabled by default to determine the performance impact (no
significant impact expected). In practice only useful when combined with
inlining since intrinsics are rarely used directly (with exception of
`unreachable` and `discriminant_value` used by built-in derive macros).

Closes #32716.
2020-11-14 22:05:54 +00:00
David Tolnay
afb817054c
Move likely/unlikely argument outside of invisible unsafe block
The previous `likely!`/`unlikely!` macros were unsound because it
permits the caller's expr to contain arbitrary unsafe code.

    pub fn huh() -> bool {
        likely!(std::ptr::read(&() as *const () as *const bool))
    }

Before: compiles cleanly.
After:

    error[E0133]: call to unsafe function is unsafe and requires unsafe function or block
       |
    70 |     likely!(std::ptr::read(&() as *const () as *const bool))
       |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ call to unsafe function
       |
       = note: consult the function's documentation for information on how to avoid undefined behavior
2020-11-14 14:03:57 -08:00
bors
98d66340d6 Auto merge of #78809 - vn-ki:fix-issue-76064, r=oli-obk
add error_occured field to ConstQualifs,

fix #76064

I wasn't sure what `in_return_place` actually did and not sure why it returns `ConstQualifs` while it's sibling functions return `bool`. So I tried to make as minimal changes to the structure as possible. Please point out whether I have to refactor it or not.

r? `@oli-obk`
cc `@RalfJung`
2020-11-14 18:03:17 +00:00
Fabian Zaiser
8cf3564310 Add underscore expressions for destructuring assignments
Co-authored-by: varkor <github@varkor.com>
2020-11-14 13:53:12 +00:00
Who? Me?!
b825ae7d28
Style nit
Co-authored-by: matthewjasper <20113453+matthewjasper@users.noreply.github.com>
2020-11-14 07:20:25 -06:00
bors
30e49a9ead Auto merge of #75272 - the8472:spec-copy, r=KodrAus
specialize io::copy to use copy_file_range, splice or sendfile

Fixes #74426.
Also covers #60689 but only as an optimization instead of an official API.

The specialization only covers std-owned structs so it should avoid the problems with #71091

Currently linux-only but it should be generalizable to other unix systems that have sendfile/sosplice and similar.

There is a bit of optimization potential around the syscall count. Right now it may end up doing more syscalls than the naive copy loop when doing short (<8KiB) copies between file descriptors.

The test case executes the following:

```
[pid 103776] statx(3, "", AT_STATX_SYNC_AS_STAT|AT_EMPTY_PATH, STATX_ALL, {stx_mask=STATX_ALL|STATX_MNT_ID, stx_attributes=0, stx_mode=S_IFREG|0644, stx_size=17, ...}) = 0
[pid 103776] write(4, "wxyz", 4)        = 4
[pid 103776] write(4, "iklmn", 5)       = 5
[pid 103776] copy_file_range(3, NULL, 4, NULL, 5, 0) = 5

```

0-1 `stat` calls to identify the source file type. 0 if the type can be inferred from the struct from which the FD was extracted
𝖬 `write` to drain the `BufReader`/`BufWriter` wrappers. only happen when buffers are present. 𝖬 ≾ number of wrappers present. If there is a write buffer it may absorb the read buffer contents first so only result in a single write. Vectored writes would also be an option but that would require more invasive changes to `BufWriter`.
𝖭 `copy_file_range`/`splice`/`sendfile` until file size, EOF or the byte limit from `Take` is reached. This should generally be *much* more efficient than the read-write loop and also have other benefits such as DMA offload or extent sharing.

## Benchmarks

```

OLD

test io::tests::bench_file_to_file_copy         ... bench:      21,002 ns/iter (+/- 750) = 6240 MB/s    [ext4]
test io::tests::bench_file_to_file_copy         ... bench:      35,704 ns/iter (+/- 1,108) = 3671 MB/s  [btrfs]
test io::tests::bench_file_to_socket_copy       ... bench:      57,002 ns/iter (+/- 4,205) = 2299 MB/s
test io::tests::bench_socket_pipe_socket_copy   ... bench:     142,640 ns/iter (+/- 77,851) = 918 MB/s

NEW

test io::tests::bench_file_to_file_copy         ... bench:      14,745 ns/iter (+/- 519) = 8889 MB/s    [ext4]
test io::tests::bench_file_to_file_copy         ... bench:       6,128 ns/iter (+/- 227) = 21389 MB/s   [btrfs]
test io::tests::bench_file_to_socket_copy       ... bench:      13,767 ns/iter (+/- 3,767) = 9520 MB/s
test io::tests::bench_socket_pipe_socket_copy   ... bench:      26,471 ns/iter (+/- 6,412) = 4951 MB/s
```
2020-11-14 12:01:55 +00:00
bors
66c1309446 Auto merge of #78959 - petrochenkov:likeuefi, r=nagisa
rustc_target: Mark UEFI targets as `is_like_windows`/`is_like_msvc`

And document what `is_like_windows` and `is_like_msvc` actually mean in more detail.

Addresses FIXMEs left from https://github.com/rust-lang/rust/pull/71030.
r? `@nagisa`
2020-11-14 09:11:25 +00:00
Joshua Nelson
03cbee84af Rename ItemEnum -> ItemKind, inner -> kind 2020-11-14 03:46:18 -05:00
bors
1a25580c6c Auto merge of #78951 - petrochenkov:unknown, r=ehuss
rustc_target: Change os and vendor values to "none" and "unknown" for some targets

Closes https://github.com/rust-lang/rust/issues/77730
r? `@ehuss`
2020-11-14 06:44:18 +00:00
bors
50d3c2a3cb Auto merge of #78736 - petrochenkov:lazyenum, r=Aaron1011
rustc_parse: Remove optimization for 0-length streams in `collect_tokens`

The optimization conflates empty token streams with unknown token stream, which is at least suspicious, and doesn't affect performance because 0-length token streams are very rare.

r? `@Aaron1011`
2020-11-14 04:21:56 +00:00
Camille GILLOT
41c44b498f Move Steal to rustc_data_structures. 2020-11-14 01:30:56 +01:00
Tomasz Miąsko
6903273339 Lower intrinsics calls: forget, size_of, unreachable, wrapping_*
This allows constant propagation to evaluate `size_of` and `wrapping_*`,
and unreachable propagation to propagate a call to `unreachable`.

The lowering is performed as a MIR optimization, rather than during MIR
building to preserve the special status of intrinsics with respect to
unsafety checks and promotion.
2020-11-14 00:00:00 +00:00
bors
b63d05a908 Auto merge of #78683 - Nemo157:issue-78673, r=lcnr
Check predicates from blanket trait impls while testing if they apply

fixes #78673
2020-11-13 23:12:01 +00:00
The8472
bbfa92c82d Always handle EOVERFLOW by falling back to the generic copy loop
Previously EOVERFLOW handling was only applied for io::copy specialization
but not for fs::copy sharing the same code.

Additionally we lower the chunk size to 1GB since we have a user report
that older kernels may return EINVAL when passing 0x8000_0000
but smaller values succeed.
2020-11-13 22:38:27 +01:00