Commit Graph

163 Commits

Author SHA1 Message Date
bors
e99a89c7c0 Auto merge of #73210 - wesleywiser:consts_in_debuginfo, r=oli-obk
[mir-opt] Allow debuginfo to be generated for a constant or a Place

Prior to this commit, debuginfo was always generated by mapping a name
to a Place. This has the side-effect that `SimplifyLocals` cannot remove
locals that are only used for debuginfo because their other uses have
been const-propagated.

To allow these locals to be removed, we now allow debuginfo to point to
a constant value. The `ConstProp` pass detects when debuginfo points to
a local with a known constant value and replaces it with the value. This
allows the later `SimplifyLocals` pass to remove the local.
2020-12-15 08:46:00 +00:00
Yuki Okushi
1b81f08d4c
Rollup merge of #79940 - matthiaskrgr:cl15ppy, r=Dylan-DPC
fix more clippy::complexity findings

fix clippy::unnecessary_filter_map
use if let Some(x) = ..  instead of ...map(|x|) to conditionally run fns that return () (clippy::option_map_unit_fn)
fix clippy::{needless_bool, manual_unwrap_or}
don't clone types that are copy (clippy::clone_on_copy)
don't convert types into identical types with .into() (clippy::useless_conversion)
use strip_prefix over slicing (clippy::manual_strip)

r? ``@Dylan-DPC``
2020-12-13 11:05:36 +09:00
bors
5bd9b60333 Auto merge of #79553 - sexxi-goose:mir_min_cap_writeback, r=nikomatsakis
Capture precise paths in THIR and MIR

This PR allows THIR and MIR to use the result of the new capture analysis to actually capture precise paths

To achieve we:
- Writeback min capture results to TypeckResults
- Move handling upvars to PlaceBuilder in mir_build
- Lower precise paths in THIR build by reading min_captures
- Search for ancestors in min_capture when trying to build a MIR place which starts off of an upvar

Closes: https://github.com/rust-lang/project-rfc-2229/issues/10

Partly implements: rust-lang/project-rfc-2229#18

Work that remains (not in this PR):
- [ ] [Known bugs when feature gate is enabled](https://github.com/rust-lang/project-rfc-2229/projects/1?card_filter_query=label%3Abug)
- [ ] Use min_capure_map for
  - [ ] Liveness analysis
  - [ ] rustc_mir/interpret/validity.rs
  - [ ] regionck
- [ ] rust-lang/project-rfc-2229#8
- [ ] remove closure_captures and upvar_capture_map

r? `@ghost`
2020-12-12 00:23:29 +00:00
Matthias Krüger
5833f74a9c use if let Some(x) = .. instead of ...map(|x|) to conditionally run fns that return () (clippy::option_map_unit_fn) 2020-12-11 23:02:19 +01:00
Aman Arora
e2efdd156b Use precise places when lowering Closures in THIR
- Closures now use closure_min_captures to figure out captured paths
- Build upvar_mutbls using closure_min_captures
- Change logic in limit_capture_mutability to differentiate b/w
  capturing parent's local variable or capturing a variable that is
  captured by the parent (in case of nested closure) using PlaceBase.

Co-authored-by: Roxane Fruytier <roxane.fruytier@hotmail.com>
2020-12-09 22:34:15 -05:00
Aman Arora
6a1d0699a4 Use Places for captures in MIR
- Use closure_min_capture maps to capture precise paths
- PlaceBuilder now searches for ancestors in min_capture list
- Add API to `Ty` to allow access to the n-th element in a
  tuple in O(1) time.

Co-authored-by: Roxane Fruytier <roxane.fruytier@hotmail.com>
2020-12-09 22:33:33 -05:00
oli
84fe7cf24e Also generate StorageDead in constants 2020-12-09 10:59:10 +00:00
Wesley Wiser
01aec8d185 [mir-opt] Allow debuginfo to be generated for a constant or a Place
Prior to this commit, debuginfo was always generated by mapping a name
to a Place. This has the side-effect that `SimplifyLocals` cannot remove
locals that are only used for debuginfo because their other uses have
been const-propagated.

To allow these locals to be removed, we now allow debuginfo to point to
a constant value. The `ConstProp` pass detects when debuginfo points to
a local with a known constant value and replaces it with the value. This
allows the later `SimplifyLocals` pass to remove the local.
2020-12-06 20:48:25 -05:00
Aman Arora
d9523622ff Move handling UpvarRef to PlaceBuilder
- This allows us to delay figuring out the index of a capture
  in the closure structure when all projections to atleast form
  a capture have been applied to the builder

Co-authored-by: Roxane Fruytier <roxane.fruytier@hotmail.com>
2020-12-06 18:30:23 -05:00
Tomasz Miąsko
91fe548825 Retain assembly operands span when lowering AST to HIR 2020-12-06 20:48:08 +01:00
Matthew Jasper
4fef39113a Avoid leaking block expression values 2020-12-04 23:07:46 +00:00
Matthew Jasper
7f3e8551dd Use record_operands_moved more aggresively 2020-12-04 22:22:52 +00:00
Matthew Jasper
b766abc88f Simplify unscheduling of drops after moves 2020-12-04 22:19:28 +00:00
Nadrieril
793c40e0bd Inline is_covered_by 2020-12-04 01:45:34 +00:00
Nadrieril
bdd2bdb53b Don't store ty and span in IntRange
We prefer to grab `ty` and `span` from `pcx`. This makes it consistent
with other constructors.
2020-11-28 22:07:15 +00:00
Nadrieril
d8983655c1 Correctly detect usize/isize range overlaps 2020-11-28 21:23:38 +00:00
Nadrieril
941c6ac1a2 Rename _match to usefulness 2020-11-27 18:43:28 +00:00
Nadrieril
2de0475826 Rename pat_constructor to Constructor::from_pat 2020-11-27 18:22:19 +00:00
Nadrieril
ba3c419a43 Move the definitions of the two Ctxts to the top 2020-11-27 18:22:19 +00:00
Nadrieril
2184a1444c Extract everything related to pattern deconstruction to a new module 2020-11-27 18:22:17 +00:00
Nadrieril
3715f1ed00 No need to expose Matrix internals 2020-11-27 18:20:30 +00:00
Nadrieril
d447bdff9b Disentangle Fields and PatStack 2020-11-27 18:20:30 +00:00
Nadrieril
b59792128c Move Constructor::apply to Fields 2020-11-27 18:20:30 +00:00
Jonas Schievink
815d96111d
Rollup merge of #79421 - camelid:_match-docs-fmt, r=petrochenkov
Fix docs formatting for `thir::pattern::_match`

They were being rendered all on one line.
2020-11-26 13:39:18 +01:00
Camelid
c5c70d4017 Fix docs formatting for thir::pattern::_match
A list was being rendered all on one line and there were other
formatting issues as well.
2020-11-25 13:23:06 -08:00
Camelid
82dc99ba7a Use the name "auto traits" everywhere in the compiler
Goodbye, OIBIT!
2020-11-24 16:25:43 -08:00
bors
c643dd2ec8 Auto merge of #79243 - Nadrieril:consolidate-tests, r=varkor
Consolidate exhaustiveness-related tests

I hunted for tests that only exercised the match exhaustiveness algorithm and regrouped them. I also improved integer-range tests since I had found them lacking while hacking around.
The interest is mainly so that one can pass `--test-args patterns` and catch most relevant tests.

r? `@varkor`
`@rustbot` modify labels: +A-exhaustiveness-checking
2020-11-22 18:29:38 +00:00
Nadrieril
82bf5b61cd Regroup many usefulness-related test in the same folder 2020-11-19 19:52:54 +00:00
Dylan DPC
5c7d530b5e
Rollup merge of #79149 - sexxi-goose:upvar_ref, r=nikomatsakis
Move capture lowering from THIR to MIR

This allows us to:
- Handle precise Places captured by a closure directly in MIR. Handling
  captures in MIR is easier since we can rely on/ tweak PlaceBuilder to
  generate `mir::Place`s that resemble how we store captures (`hir::Place`).

- Handle `let _ = x` case when feature `capture_disjoint_fields`
  is enabled directly in MIR. This is required to be done in MIR since
  patterns are desugared in MIR.

Closes: rust-lang/project-rfc-2229#25

r? ```@nikomatsakis```
2020-11-19 16:26:39 +01:00
bors
8256379832 Auto merge of #78995 - Nadrieril:clean-empty-match, r=varkor
Handle empty matches cleanly in exhaustiveness checking

This removes the special-casing of empty matches that was done in `check_match`. This fixes most of https://github.com/rust-lang/rust/issues/55123.
Somewhat unrelatedly, I also made `_match.rs` more self-contained, because I think it's cleaner.

r? `@varkor`
`@rustbot` modify labels: +A-exhaustiveness-checking
2020-11-18 21:24:40 +00:00
Aman Arora
9f70e782f7 Remove THIR::ExprKind::SelfRef
ExprKind::SelfRef was used to express accessing `self` in
the desugared Closure/Generator struct when lowering captures in THIR.

Since we handle captures in MIR now, we don't need `ExprKind::Self`.
2020-11-17 17:49:42 -05:00
Aman Arora
7faebe57b2 Move capture lowering from THIR to MIR
This allows us to:
- Handle precise Places captured by a closure directly in MIR. Handling
captures in MIR is easier since we can rely on/ tweak PlaceBuilder to
generate `mir::Place`s that resemble how we store captures (`hir::Place`).
- Allows us to handle `let _ = x` case when feature `capture_disjoint_fields`
is enabled directly in MIR. This is required to be done in MIR since
patterns are desugared in MIR.
2020-11-17 17:49:42 -05:00
Mara Bos
b6f52410bb
Rollup merge of #79072 - oli-obk:byte_str_pat, r=estebank
Fix exhaustiveness in case a byte string literal is used at slice type

fixes #79048
2020-11-17 16:13:53 +01:00
oli
a1cdf722f4 Fix exhaustiveness in case a byte string literal is used at slice type 2020-11-17 09:07:23 +00:00
bors
b5c37e86ff Auto merge of #78801 - sexxi-goose:min_capture, r=nikomatsakis
RFC-2229: Implement Precise Capture Analysis

### This PR introduces
- Feature gate for RFC-2229 (incomplete) `capture_disjoint_field`
- Rustc Attribute to print out the capture analysis `rustc_capture_analysis`
- Precise capture analysis

### Description of the analysis
1. If the feature gate is not set then all variables that are not local to the closure will be added to the list of captures. (This is for backcompat)
2. The rest of the analysis is based entirely on how the captured `Place`s are used within the closure. Precise information (i.e. projections) about the `Place` is maintained throughout.
3. To reduce the amount of information we need to keep track of, we do a minimization step. In this step, we determine a list such that no Place within this list represents an ancestor path to another entry in the list.  Check rust-lang/project-rfc-2229#9 for more detailed examples.
4. To keep the compiler functional as before we implement a Bridge between the results of this new analysis to existing data structures used for closure captures. Note the new capture analysis results are only part of MaybeTypeckTables that is the information is only available during typeck-ing.

### Known issues
- Statements like `let _ = x` will make the compiler ICE when used within a closure with the feature enabled. More generally speaking the issue is caused by `let` statements that create no bindings and are init'ed using a Place expression.

### Testing
We removed the code that would handle the case where the feature gate is not set, to enable the feature as default and did a bors try and perf run. More information here: #78762

### Thanks
This has been slowly in the works for a while now.
I want to call out `@Azhng` `@ChrisPardy` `@null-sleep` `@jenniferwills` `@logmosier` `@roxelo` for working on this and the previous PRs that led up to this, `@nikomatsakis` for guiding us.

Closes rust-lang/project-rfc-2229#7
Closes rust-lang/project-rfc-2229#9
Closes rust-lang/project-rfc-2229#6
Closes rust-lang/project-rfc-2229#19

r? `@nikomatsakis`
2020-11-17 03:56:03 +00:00
Bastian Kauschke
2bf93bd852 compiler: fold by value 2020-11-16 22:34:57 +01:00
Nadrieril
36e3409f67 Apply suggestions from code review
Co-authored-by: varkor <github@varkor.com>
2020-11-16 01:00:33 +00:00
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
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
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
Camille GILLOT
41c44b498f Move Steal to rustc_data_structures. 2020-11-14 01:30:56 +01:00
Nadrieril
b9da2b372f Factor out match usefulness computation in check_match
This make `_match` a lot more self-contained
2020-11-12 18:17:42 +00:00
Nadrieril
d5a7ec0929 Unreachable subpatterns are rare
We may as well leave early when we know there's nothing to report.
2020-11-12 17:42:02 +00:00
Nadrieril
b025813f03 Handle empty matches cleanly 2020-11-12 17:41:36 +00:00
Aman Arora
127a6ede1d Use Places to express closure/generator Captures
Co-authored-by: Archer Zhang <archer.xn@gmail.com>
2020-11-10 20:44:47 -05:00
mark
43e4783ce3 address reviewer comments 2020-11-09 12:19:34 -06:00
Dylan DPC
abaa78baeb
Rollup merge of #78748 - fanzier:tuple-assignment, r=petrochenkov
Implement destructuring assignment for tuples

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

Quick summary: This change allows destructuring the LHS of an assignment if it's a (possibly nested) tuple.
It is implemented via a desugaring (AST -> HIR lowering) as follows:
```rust
(a,b) = (1,2)
```
... becomes ...
```rust
{
  let (lhs0,lhs1) = (1,2);
  a = lhs0;
  b = lhs1;
}
```

Thanks to `@varkor` who helped with the implementation, particularly around default binding modes.

r? `@petrochenkov`
2020-11-09 01:13:44 +01:00
mark
459dae94a1 fix #72680 by explicitly checking for or-pattern before test 2020-11-07 23:22:47 -06:00
Joshua Nelson
622c48e4f1 Allow making RUSTC_BOOTSTRAP conditional on the crate name
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`

  There is a user-facing change here: things like `RUSTC_BOOTSTRAP=0` no
  longer active 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.

- Add tests

  Check against `Cheat`, not whether nightly features are allowed.
  Nightly features are always allowed on the nightly channel.

- Only call `is_nightly_build()` once within a function

- Use booleans consistently for rustc_incremental

  Sessions can't be passed through threads, so `read_file` couldn't take a
  session. To be consistent, also take a boolean in `write_file_header`.
2020-11-07 13:45:11 -05:00
Fabian Zaiser
3a7a997323 Implement destructuring assignment for tuples
Co-authored-by: varkor <github@varkor.com>
2020-11-07 13:17:19 +00:00