Commit Graph

472 Commits

Author SHA1 Message Date
Jonas Schievink
6522868664
Rollup merge of #77251 - dtolnay:drop, r=Aaron1011
Bypass const_item_mutation if const's type has Drop impl

Follow-up to #75573. This PR disables the const_item_mutation lint in cases that the const has a Drop impl which observes the mutation.

```rust
struct Log { msg: &'static str }
const LOG: Log = Log { msg: "" };
impl Drop for Log {
    fn drop(&mut self) { println!("{}", self.msg); }
}

LOG.msg = "wow";  // prints "wow"
```

r? @Aaron1011
2020-10-03 00:31:12 +02:00
bors
8876ffc923 Auto merge of #77462 - jonas-schievink:rollup-m0rqdh5, r=jonas-schievink
Rollup of 12 pull requests

Successful merges:

 - #76101 (Update RELEASES.md for 1.47.0)
 - #76739 (resolve: prohibit anon const non-static lifetimes)
 - #76811 (Doc alias name restriction)
 - #77405 (Add tracking issue of iter_advance_by feature)
 - #77409 (Add example for iter chain struct)
 - #77415 (Better error message for `async` blocks in a const-context)
 - #77423 (Add `-Zprecise-enum-drop-elaboration`)
 - #77432 (Use posix_spawn on musl targets)
 - #77441 (Fix AVR stack corruption bug)
 - #77442 (Clean up on example doc fixes for ptr::copy)
 - #77444 (Fix span for incorrect pattern field and add label)
 - #77453 (Stop running macOS builds on Azure Pipelines)

Failed merges:

r? `@ghost`
2020-10-02 19:42:07 +00:00
Jonas Schievink
1e3c7e214a
Rollup merge of #77423 - ecstatic-morse:discriminant-switch-effect-config, r=pnkfelix
Add `-Zprecise-enum-drop-elaboration`

Its purpose is to assist in debugging #77382 and #74551. Passing `-Zprecise-enum-drop-elaboration=no` will turn off the added precision that seems to be causing issues on some platforms. This assumes that we can reproduce #77382 on the latest master. I should have done this earlier. Oh well.

cc @cuviper
r? @pnkfelix
2020-10-02 20:27:09 +02:00
Jonas Schievink
cac5352e33
Rollup merge of #77415 - ecstatic-morse:const-checking-async-block, r=oli-obk
Better error message for `async` blocks in a const-context

Improves the error message for the case in #77361.

r? @oli-obk
2020-10-02 20:27:08 +02:00
Jonas Schievink
acc150b2e9 validate: skip debuginfo 2020-10-02 16:50:29 +02:00
Jonas Schievink
c1a431edc3 validate: storage must be allocated on local use 2020-10-02 16:11:47 +02:00
Wesley Wiser
f9d7720be7 Disable the SimplifyArmIdentity mir-opt
The optimization still has some bugs that need to be worked out
such as #77359.

We can try re-enabling this again after the known issues are resolved.
2020-10-01 20:29:53 -04:00
David Tolnay
804d159c62
Fixme with link for re-enabling const mutation lint for Drop consts 2020-10-01 13:41:43 -07:00
Dylan MacKenzie
6691d11234 Add -Zprecise-enum-drop-elaboration
Its purpose is to assist in debugging #77382 and #74551.
2020-10-01 11:31:43 -07:00
Dylan MacKenzie
77e6c56ab6 Unify &mut and &raw mut const-checking errors 2020-10-01 11:04:33 -07:00
Dylan MacKenzie
50e0c0d97b Give better const-checking error for async blocks 2020-10-01 10:11:58 -07:00
bors
9cba260df0 Auto merge of #74839 - alarsyo:multiple_return_terminators, r=oli-obk
Implement multiple return terminator optimization

Closes #72022
2020-10-01 09:52:58 +00:00
Antoine Martin
f54bfac074 Implement multiple return terminators optimization 2020-10-01 10:06:37 +02:00
bors
fc42fb8e70 Auto merge of #77354 - ecstatic-morse:const-checking-moar-errors, r=oli-obk
Overhaul const-checking diagnostics

The primary purpose of this PR was to remove `NonConstOp::STOPS_CONST_CHECKING`, which causes any additional errors found by the const-checker to be silenced. I used this flag to preserve diagnostic parity with `qualify_min_const_fn.rs`, which has since been removed.

However, simply removing the flag caused a deluge of errors in some cases, since an error would be emitted any time a local or temporary had a wrong type. To remedy this, I added an alternative system (`DiagnosticImportance`) to silence additional error messages that were likely to distract the user from the underlying issue. When an error of the highest importance occurs, all less important errors are silenced. When no error of the highest importance occurs, all less important errors are emitted after checking is complete. Following the suggestions from the important error is usually enough to fix the less important errors, so this should lead to better UX most of the time.

There's also some unrelated diagnostics improvements in this PR isolated in their own commits. Splitting them out would be possible, but a bit of a pain. This isn't as tidy as some of my other PRs, but it should *only* affect diagnostics, never whether or not something passes const-checking. Note that there are a few trivial exceptions to this, like banning `Yield` in all const-contexts, not just `const fn`.

As always, meant to be reviewed commit-by-commit.

r? `@oli-obk`
2020-10-01 07:38:47 +00:00
Oliver Scherer
8f9472cc9e Only mention that a stack frame is being popped when starting to do so 2020-10-01 08:32:24 +02:00
David Tolnay
75c2fdf34a
Warn on method call mutating const, even if it has destructor 2020-09-30 22:19:45 -07:00
David Tolnay
41baa090ad
Skip dropck::check_drop_impl in is_const_item_without_destructor
adt_destructor by default also validates the Drop impl using
dropck::check_drop_impl, which contains an expect_local(). This
leads to ICE in check_const_item_mutation if the const's type is
not a local type.

    thread 'rustc' panicked at 'DefId::expect_local: `DefId(5:4805 ~ alloc[d7e9]::vec::{impl#50})` isn't local', compiler/rustc_span/src/def_id.rs:174:43
    stack backtrace:
       0: rust_begin_unwind
       1: rustc_span::def_id::DefId::expect_local::{{closure}}
       2: rustc_typeck::check::dropck::check_drop_impl
       3: rustc_middle::ty::util::<impl rustc_middle::ty::context::TyCtxt>::calculate_dtor::{{closure}}
       4: rustc_middle::ty::trait_def::<impl rustc_middle::ty::context::TyCtxt>::for_each_relevant_impl
       5: rustc_middle::ty::util::<impl rustc_middle::ty::context::TyCtxt>::calculate_dtor
       6: rustc_typeck::check::adt_destructor
       7: rustc_middle::ty::query::<impl rustc_query_system::query::config::QueryAccessors<rustc_middle::ty::context::TyCtxt> for rustc_middle::ty::query::queries::adt_destructor>::compute
       8: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl
       9: rustc_query_system::query::plumbing::get_query_impl
      10: rustc_mir::transform::check_const_item_mutation::ConstMutationChecker::is_const_item_without_destructor
2020-09-30 21:58:13 -07:00
David Tolnay
bb760b53bf
Simplify defid destructor check 2020-09-30 21:45:56 -07:00
David Tolnay
0dfe7b6434
Add justification of the destructor filter 2020-09-30 21:45:56 -07:00
David Tolnay
17db1cb5d5
Bypass const_item_mutation if const's type has Drop impl 2020-09-30 21:45:56 -07:00
Dylan DPC
cc1513b860
Rollup merge of #77360 - oli-obk:zst_const_pat_regression, r=RalfJung
References to ZSTs may be at arbitrary aligned addresses

fixes #77320

r? @RalfJung
2020-10-01 02:13:48 +02:00
Dylan DPC
849e5636ea
Rollup merge of #77343 - varkor:rustc_args_required_const-validation, r=lcnr
Validate `rustc_args_required_const`

Fixes https://github.com/rust-lang/rust/issues/74608.
2020-10-01 02:13:44 +02:00
Dylan DPC
73258f87ea
Rollup merge of #77324 - Aaron1011:fix/const-item-mutation-ptr, r=petrochenkov
Don't fire `const_item_mutation` lint on writes through a pointer

Fixes #77321
2020-10-01 02:13:43 +02:00
Jonas Schievink
248d6bf1e2
Rollup merge of #77037 - matthiaskrgr:cl42ppy, r=Dylan-DPC
more tiny clippy cleanups

commits stand alone and can be reviewed one by one
2020-09-30 20:56:05 +02:00
Dylan MacKenzie
1301f43119 Remove E0019, use E0015 for inline assembly in a const 2020-09-30 11:29:25 -07:00
Dylan MacKenzie
0c26144b1a Better span for attribute suggestions
`def_span` has the same issues as `body.span`, so do it this way instead.
2020-09-30 11:29:16 -07:00
varkor
609786dbd8 Validate rustc_args_required_const 2020-09-30 11:59:44 +01:00
Oliver Scherer
ce6c25da58 References to ZSTs may be at arbitrary aligned addresses 2020-09-30 10:40:49 +02:00
Dylan MacKenzie
1513904c1c Remove default build_error impl
Now all structured errors must have their own error code
2020-09-29 21:17:48 -07:00
Dylan MacKenzie
287993c961 Remove machinery for halting error output 2020-09-29 19:20:33 -07:00
Dylan MacKenzie
e02ea835a7 Don't stop const-checking after erroneous trait bound 2020-09-29 19:20:33 -07:00
Dylan MacKenzie
37f37dc5ba Emit multiple function pointer errors from const-checker 2020-09-29 19:20:33 -07:00
Dylan MacKenzie
b400871b9c Don't emit duplicate errors for the return place 2020-09-29 19:20:33 -07:00
Dylan MacKenzie
5b3145574e Priority levels 2020-09-29 19:20:33 -07:00
Dylan MacKenzie
a23297f5c0 Bless mut tests 2020-09-29 19:20:33 -07:00
Dylan MacKenzie
b518ccb4c3 Give MutDeref a real error message 2020-09-29 19:20:33 -07:00
Dylan MacKenzie
de35c4293d Remove ops::non_const
This helper function was meant to reduce code duplication between
const-checking pre- and post-drop-elaboration. Most of the functionality
is only relevant for the pre-drop-elaboration pass.
2020-09-29 19:20:33 -07:00
Dylan MacKenzie
ce50939952 Fix "unstable in stable" error
The "otherwise" note is printed before the suggestion currently.
2020-09-29 19:20:33 -07:00
Dylan MacKenzie
782a595d7c Return a DiagnosticBuilder from structured errors
This ensures that `emit_error` will actually cause compilation to fail.
2020-09-29 19:20:33 -07:00
Dylan MacKenzie
20e07e7b8e Forbid generator-specific MIR in all const-contexts 2020-09-29 19:20:33 -07:00
Dylan MacKenzie
c38aca0502 delay_span_bug if const-checking an async function
This errors during AST lowering. Any errors we emit here are just noise.
2020-09-29 19:20:33 -07:00
Dylan MacKenzie
25c7753eee Continue after impl Trait in const fn 2020-09-29 19:13:11 -07:00
Dylan MacKenzie
325b7d42ec Continue const-checking after errors when easy
This doesn't change any UI test output
2020-09-29 17:38:28 -07:00
Aaron Hill
c6107c53d7
Don't fire const_item_mutation lint on writes through a pointer
Fixes #77321
2020-09-28 23:51:57 -04:00
Oliver Scherer
43c181bac4 Use tracing spans to trace the entire MIR interp stack 2020-09-28 20:07:57 +02:00
bors
fc2daaae61 Auto merge of #77302 - RalfJung:rollup-n8gg3v6, r=RalfJung
Rollup of 7 pull requests

Successful merges:

 - #76454 (UI to unit test for those using Cell/RefCell/UnsafeCell)
 - #76474 (Add option to pass a custom codegen backend from a driver)
 - #76711 (diag: improve closure/generic parameter mismatch)
 - #77170 (Remove `#[rustc_allow_const_fn_ptr]` and add `#![feature(const_fn_fn_ptr_basics)]`)
 - #77194 (Add doc alias for iterator fold)
 - #77288 (fix building libstd for Miri on macOS)
 - #77295 (Update unstable-book: Fix ABNF in inline assembly docs)

Failed merges:

r? `@ghost`
2020-09-28 18:02:45 +00:00
Ralf Jung
85a59d40f1
Rollup merge of #77170 - ecstatic-morse:const-fn-ptr, r=oli-obk
Remove `#[rustc_allow_const_fn_ptr]` and add `#![feature(const_fn_fn_ptr_basics)]`

`rustc_allow_const_fn_ptr` was a hack to work around the lack of an escape hatch for the "min `const fn`" checks in const-stable functions. Now that we have co-opted `allow_internal_unstable` for this purpose, we no longer need a bespoke attribute.

Now this functionality is gated under `const_fn_fn_ptr_basics` (how concise!), and `#[allow_internal_unstable(const_fn_fn_ptr_basics)]` replaces `#[rustc_allow_const_fn_ptr]`. `const_fn_fn_ptr_basics` allows function pointer types to appear in the arguments and locals of a `const fn` as well as function pointer casts to be performed inside a `const fn`. Both of these were allowed in constants and statics already. Notably, this does **not** allow users to invoke function pointers in a const context. Presumably, we will use a nicer name for that (`const_fn_ptr`?).

r? @oli-obk
2020-09-28 18:39:44 +02:00
bors
d62d3f7fa9 Auto merge of #76899 - wesleywiser:experimental_unsound_mir_opts_flag, r=oli-obk
[mir-opt] Introduce a new flag to enable experimental/unsound mir opts

This implements part of https://github.com/rust-lang/compiler-team/issues/319. The exact name of this flag was not decided as part of that MCP and some people expressed that it should include "unsound" in some way.

I've chosen to use `enable-experimental-unsound-mir-opts` as the name. While long, I don't think that matters too much as really it will only be used by some mir-opt tests. If you object or have a better name, please leave a comment!

r? `@oli-obk`
cc `@rust-lang/wg-mir-opt` `@RalfJung`
2020-09-28 15:32:27 +00:00
bors
535d27ac9a Auto merge of #77236 - matthewjasper:defer-typeof-impl-trait, r=davidtwco
Compute underlying type of impl trait types later in compilation

Also change a `bug!` to `delay_span_bug`
Closes #74018
2020-09-28 12:47:23 +00:00
Wesley Wiser
b9d0ea95c8 [mir-opt] Introduce a new flag to enable experimental/unsound mir opts 2020-09-27 19:21:01 -04:00
bors
c0b15cc6ed Auto merge of #77242 - ecstatic-morse:dataflow-switch-int, r=jonas-schievink
Replace `discriminant_switch_effect` with more general version

#68528 added a new edge-specific effect for `SwitchInt` terminators, `discriminant_switch_effect`, to the dataflow framework. While this accomplished the short-term goal of making drop elaboration more precise, it wasn't really useful in other contexts: It only supported `SwitchInt`s on the discriminant of an `enum` and did not allow effects to be applied along the "otherwise" branch. In const-propagation, for example, arbitrary edge-specific effects for the targets of a `SwitchInt` can be used to remember the value a `match` scrutinee must have in each arm.

This PR replaces `discriminant_switch_effect` with a more general `switch_int_edge_effects` method. The new method has a slightly different interface from the other edge-specific effect methods (e.g. `call_return_effect`). This divergence is explained in the new method's documentation, and reading the changes to the various dataflow impls as well as `direction.rs` should further clarify things. This PR should not change behavior.
2020-09-27 21:54:49 +00:00
Dylan MacKenzie
3cbd17fcc6 Remove rustc_allow_const_fn_ptr
This was a hack to work around the lack of an escape hatch for the "min
`const fn`" checks in const-stable functions. Now that we have co-opted
`allow_internal_unstable` for this purpose, we no longer need the
bespoke attribute.
2020-09-27 10:46:41 -07:00
Dylan MacKenzie
1ff143191c Add a feature gate for basic function pointer use in const fn 2020-09-27 10:46:41 -07:00
Jonas Schievink
9f086fcb00
Rollup merge of #77203 - ecstatic-morse:const-stability-attr-checks, r=oli-obk
Check for missing const-stability attributes in `rustc_passes`

Currently, this happens as a side effect of `is_min_const_fn`, which is non-obvious. Also adds a test for this case, since we didn't seem to have one before.
2020-09-27 18:37:21 +02:00
Dylan MacKenzie
c0cd1b0a26 Remove intra-doc link 2020-09-26 17:29:55 -07:00
Jonas Schievink
aa35c527fd
Rollup merge of #77231 - oli-obk:clippy_const_fn, r=Manishearth
Move helper function for `missing_const_for_fn` out of rustc to clippy

cc @rust-lang/clippy @ecstatic-morse #76618

r? @Manishearth

I also removed all support for suggesting a function could be `const fn` when that would require feature gates to actually work.

This means we'll now have to maintain this ourselves in clippy, but that's how most lints work anyway, so...
2020-09-27 01:53:27 +02:00
Jonas Schievink
6b8fb3fbd8
Rollup merge of #77107 - bugadani:perf, r=oli-obk
Enable const propagation into operands at mir_opt_level=2

Feature was added in #74507 but gated with `mir_opt_level>=3` because of compile time regressions. Let's see whether the LLVM 11 update solves that.

As the [perf results](https://github.com/rust-lang/rust/pull/77107#issuecomment-697668154) show, enabling this optimization results in a lot less regression as before.

cc @oli-obk

r? @ghost
2020-09-27 01:53:16 +02:00
Dylan MacKenzie
2364b58b87 Update dataflow impls to reflect new interface 2020-09-26 15:15:06 -07:00
Dylan MacKenzie
43e6ef876f Update engine to use new interface 2020-09-26 15:15:06 -07:00
Dylan MacKenzie
4c5f9f742c Replace discriminant_switch_effect with more general version
...that allows arbitrary effects on each edge of a `SwitchInt`
terminator.
2020-09-26 14:50:47 -07:00
Matthew Jasper
ef83742b2b Delay bug for non-universal regions in member constraints 2020-09-26 17:16:25 +01:00
Oliver Scherer
1b843896c8 Move qualify_min_const_fn out of rustc into clippy 2020-09-26 16:08:24 +02:00
Ralf Jung
9e02642fb3
Rollup merge of #77211 - est31:remove_unused_allow, r=oli-obk
Remove unused #[allow(...)] statements from compiler/
2020-09-26 12:58:34 +02:00
Ralf Jung
3b544e73ae
Rollup merge of #77122 - ecstatic-morse:const-fn-arithmetic, r=RalfJung,oli-obk
Add `#![feature(const_fn_floating_point_arithmetic)]`

cc #76618

This is a template for splitting up `const_fn` into granular feature gates. I think this will make it easier, both for us and for users, to track stabilization of each individual feature. We don't *have* to do this, however. We could also keep stabilizing things out from under `const_fn`.

cc @rust-lang/wg-const-eval
r? @oli-obk
2020-09-26 12:58:20 +02:00
Ralf Jung
ac8169dc10
Rollup merge of #77093 - lcnr:const-generics-infer-warning, r=varkor
merge `need_type_info_err(_const)`

I hoped that this would automatically solve #76737 but it doesn't quite seem like it

fixes #77092

r? @varkor
2020-09-26 12:58:17 +02:00
Bastian Kauschke
32195ac8f4 rename functions 2020-09-26 10:28:15 +02:00
bors
fd15e6180d Auto merge of #70743 - oli-obk:eager_const_to_pat_conversion, r=eddyb
Fully destructure constants into patterns

r? `@varkor`

as discussed in https://rust-lang.zulipchat.com/#narrow/stream/131828-t-compiler/topic/constants.20in.20patterns/near/192789924

we should probably crater it once reviewed
2020-09-26 06:44:28 +00:00
est31
12187b7f86 Remove unused #[allow(...)] statements from compiler/ 2020-09-26 01:25:55 +02:00
marmeladema
75130b06bf Avoid calling Symbol::interner in compute_codegen_unit_name 2020-09-25 22:46:15 +01:00
marmeladema
657ecdb75e Rename DefPathData::get_name() to DefPathData::name() 2020-09-25 22:46:15 +01:00
marmeladema
9f50c49117 Implement Display for DisambiguatedDefPathData and DefPathData 2020-09-25 22:46:15 +01:00
marmeladema
f1878d19fa Move from {{closure}}#0 syntax to {closure#0} for (def) path components 2020-09-25 22:46:14 +01:00
Dylan MacKenzie
76c6f2dc3f No need to call is_min_const_fn for side-effects 2020-09-25 14:31:32 -07:00
Dylan MacKenzie
11bfc60a4b Change error in fn_queries to delay_span_bug
This should be caught by the new check in `rustc_passes`. At some point,
this function will be removed entirely.
2020-09-25 14:31:32 -07:00
bors
c6e4db620a Auto merge of #77198 - jonas-schievink:rollup-i59i41h, r=jonas-schievink
Rollup of 15 pull requests

Successful merges:

 - #76932 (Relax promises about condition variable.)
 - #76973 (Unstably allow assume intrinsic in const contexts)
 - #77005 (BtreeMap: refactoring around edges)
 - #77066 (Fix dest prop miscompilation around references)
 - #77073 (dead_code: look at trait impls even if they don't contain items)
 - #77086 (Include libunwind in the rust-src component.)
 - #77097 (Make [].as_[mut_]ptr_range() (unstably) const.)
 - #77106 (clarify that `changelog-seen = 1` goes to the beginning of config.toml)
 - #77120 (Add `--keep-stage-std` to `x.py` for keeping only standard library artifacts)
 - #77126 (Invalidate local LLVM cache less often)
 - #77146 (Install std for non-host targets)
 - #77155 (remove enum name from ImplSource variants)
 - #77176 (Removing erroneous semicolon in transmute documentation)
 - #77183 (Allow multiple allow_internal_unstable attributes)
 - #77189 (Remove extra space from vec drawing)

Failed merges:

r? `@ghost`
2020-09-25 19:35:33 +00:00
Jonas Schievink
e739468f97
Rollup merge of #77155 - lcnr:ImplSource, r=ecstatic-morse
remove enum name from ImplSource variants

This is quite a lot cleaner in my opinion.
2020-09-25 19:42:48 +02:00
Jonas Schievink
452aa759b7
Rollup merge of #77066 - jonas-schievink:dest-prop-borrow, r=oli-obk
Fix dest prop miscompilation around references

Closes https://github.com/rust-lang/rust/issues/77002
2020-09-25 19:42:33 +02:00
Jonas Schievink
1b8c939a8d
Rollup merge of #76973 - lzutao:unstably-const-assume, r=oli-obk
Unstably allow assume intrinsic in const contexts

Not sure much about this usage because there are concerns
about [blocking  optimization][1] and [slowing down LLVM][2] when using `assme` intrinsic
in inline functions.
But since Oli suggested in https://github.com/rust-lang/rust/issues/76960#issuecomment-695772221,
here we are.

[1]: https://github.com/rust-lang/rust/pull/54995#issuecomment-429302709
[2]: https://github.com/rust-lang/rust/issues/49572#issuecomment-589615423
2020-09-25 19:42:29 +02:00
Dylan MacKenzie
2049052cb9 Put floating point arithmetic behind its own feature gate
This refactors handling of `Rvalue::{Unary,Binary}Op` in the
const-checker. Now we `span_bug` if there's an unexpected type in a
primitive operation. This also allows unary negation on
`char` values through the const-checker because it makes the code a bit
cleaner. `char` does not actually support these operations, and if it
did, we could evaluate them at compile-time.
2020-09-25 10:37:52 -07:00
Dylan MacKenzie
0d2521aaf7 Add const_fn_floating_point_arithmetic 2020-09-25 10:37:52 -07:00
bors
10ef7f9ebf Auto merge of #77157 - tmiasko:simplify-cfg-dup, r=jonas-schievink
Remove duplicated SimplifyCfg pass
2020-09-25 17:27:52 +00:00
bors
9d74efe32e Auto merge of #76844 - simonvandel:fix-76803, r=wesleywiser
Fix #76803 miscompilation

Fixes #76803
Seems like it was an oversight that the discriminant value being set was not compared to the target value from the SwitchInt, as a comment says this is a requirement for the optimization to be sound.

r? `@wesleywiser` since you are probably familiar with the optimization and made #76837 to workaround the bug
2020-09-25 04:17:03 +00:00
Jonas Schievink
8515efb193
Rollup merge of #77165 - simonvandel:do-not-fire-on-drop-and-replace, r=oli-obk
Followup to #76673

Resolves https://github.com/rust-lang/rust/pull/76673#discussion_r494426303
r? @tmiasko
2020-09-25 02:29:52 +02:00
Jonas Schievink
b8d158b0f8
Rollup merge of #77160 - ecstatic-morse:const-fn-transmute-suggestion, r=oli-obk
Suggest `const_fn_transmute`, not `const_fn`

More fallout from #76850 in the vein of #77134. The fix is the same. I looked through the structured errors file and didn't see any more of this kind of diagnostics bug.

r? @oli-obk
2020-09-25 02:29:49 +02:00
Jonas Schievink
473ae229f0
Rollup merge of #77136 - ecstatic-morse:issue-77134, r=oli-obk
Suggest `const_mut_refs`, not `const_fn` for mutable references in `const fn`

Resolves #77134.

Prior to #76850, most uses of `&mut` in `const fn` ~~required~~ involved two feature gates, `const_mut_refs` and `const_fn`. The first allowed all mutable borrows of locals. The second allowed only locals, arguments and return values whose types contained `&mut`. I switched the second check to the `const_mut_refs` gate. However, I forgot update the error message with the new suggestion.

Alternatively, we could revert to having two different feature gates for this. OP's code never borrows anything mutably, so it didn't need `const_mut_refs` in the past, only `const_fn`. I'd prefer to keep everything under a single gate, however.

r? @oli-obk
2020-09-25 02:29:47 +02:00
Jonas Schievink
d766c239bd
Rollup merge of #76724 - ecstatic-morse:dataflow-pass-names, r=lcnr
Allow a unique name to be assigned to dataflow graphviz output

Previously, if the same analysis were invoked multiple times in a single compilation session, the graphviz output for later runs would overwrite that of previous runs. Allow callers to add a unique identifier to each run so this can be avoided.
2020-09-25 02:29:31 +02:00
Bastian Kauschke
ff7009a4d2 nit 2020-09-24 22:03:39 +02:00
Bastian Kauschke
e5430e5306 the two hardest things in programming, names and... 2020-09-24 22:01:46 +02:00
Dylan MacKenzie
ebf024bba8 Suggest const_fn_transmute instead of const_fn 2020-09-24 12:07:41 -07:00
Simon Vandel Sillesen
7dec440340 Resolve https://github.com/rust-lang/rust/pull/76673#discussion_r494426303 2020-09-24 21:02:53 +02:00
Bastian Kauschke
1857184cd1 remove enum name from ImplSource variants 2020-09-24 19:22:36 +02:00
Matthias Krüger
d7a5c574b1 use std::mem::take(x) instead of std::mem::replace(x, Default::default()) (clippy::mem_replace_with_default) 2020-09-24 13:38:08 +02:00
Matthias Krüger
2ad46acd7f EarlyOtherwiseBranch::run_pass(): don't convert Place to Place (clippy::useless_conversion) 2020-09-24 13:38:07 +02:00
bors
5562bb6d74 Auto merge of #76748 - tmiasko:no-op-jumps, r=matthewjasper
Fix underflow when calculating the number of no-op jumps folded

When removing unwinds to no-op blocks and folding jumps to no-op blocks,
remove the unwind target first. Otherwise we cannot determine if target
has been already folded or not.

Previous implementation incorrectly assumed that all resume targets had
been folded already, occasionally resulting in an underflow:

```
remove_noop_landing_pads: removed 18446744073709551613 jumps and 3 landing pads
```
2020-09-24 05:57:06 +00:00
Dylan MacKenzie
a320ef751b Suggest const_mut_refs for mutable references in const fn 2020-09-23 21:04:07 -07:00
Tomasz Miąsko
a09d607844 Remove duplicated SimplifyCfg pass 2020-09-24 00:00:00 +00:00
bors
c35177582b Auto merge of #77102 - Dylan-DPC:rollup-2jfrg3u, r=Dylan-DPC
Rollup of 9 pull requests

Successful merges:

 - #76898 (Record `tcx.def_span` instead of `item.span` in crate metadata)
 - #76939 (emit errors during AbstractConst building)
 - #76965 (Add cfg(target_has_atomic_equal_alignment) and use it for Atomic::from_mut.)
 - #76993 (Changing the alloc() to accept &self instead of &mut self)
 - #76994 (fix small typo in docs and comments)
 - #77017 (Add missing examples on Vec iter types)
 - #77042 (Improve documentation for ToSocketAddrs)
 - #77047 (Miri: more informative deallocation error messages)
 - #77055 (Add #[track_caller] to more panicking Cell functions)

Failed merges:

r? `@ghost`
2020-09-23 22:34:44 +00:00
bors
8b4085359a Auto merge of #76673 - simonvandel:remove-unneeded-drops, r=oli-obk
MIR pass to remove unneeded drops on types not needing drop

This is heavily dependent on MIR inlining running to actually see the drop statement.

Do we want to special case replacing a call to std::mem::drop with a goto aswell?
2020-09-23 20:13:47 +00:00
Dániel Buga
90c7731f6c Enable const prop into operands at mir_opt_level=2 2020-09-23 19:03:10 +02:00
Dylan DPC
f8dec3d054
Rollup merge of #77047 - RalfJung:miri-dealloc, r=oli-obk
Miri: more informative deallocation error messages

Make sure we show the affected AllocId.

r? @oli-obk
2020-09-23 14:54:13 +02:00
Dylan DPC
bcdbe79f0c
Rollup merge of #76994 - yuk1ty:fix-small-typo, r=estebank
fix small typo in docs and comments

Fixed `the the` to `the`, as far as I found.
2020-09-23 14:54:07 +02:00
bors
feca2c229e Auto merge of #76659 - simonvandel:76432, r=oli-obk
SimplifyComparisonIntegral: fix miscompilation

Fixes #76432
Only insert StorageDeads if we actually removed one.
Fixes an issue where we added StorageDead to a place with no StorageLive

r? `@oli-obk`
2020-09-23 08:23:00 +00:00
Bastian Kauschke
45d92b43e3 merge need_type_info_err(_const) 2020-09-23 09:24:58 +02:00
Simon Vandel Sillesen
b6f51d6d6a cleanup cfg after optimization 2020-09-22 23:09:07 +02:00
Simon Vandel Sillesen
f472303a93 The optimization should also apply for DropAndReplace 2020-09-22 23:09:07 +02:00
Simon Vandel Sillesen
d3338dcf4d Get LocalDefId from source instead of passing in 2020-09-22 23:09:07 +02:00
Simon Vandel Sillesen
b4bdaa14f2 Suggestion from review
Co-authored-by: Andreas Jonson <andjo403@users.noreply.github.com>
2020-09-22 23:09:07 +02:00
Simon Vandel Sillesen
290dca1781 MIR pass to remove unneeded drops on types not needing drop
This is heavily dependent on MIR inlining running to actually see the drop statement
2020-09-22 23:09:07 +02:00
Jonas Schievink
4b6a4821b7 Fix dest prop miscompilation around references 2020-09-22 20:19:00 +02:00
Dylan MacKenzie
186d148b4c Use correct feature gate for unsizing casts 2020-09-22 10:22:50 -07:00
Dylan MacKenzie
08e3822d9a Replace missing comment 2020-09-22 10:05:58 -07:00
Dylan MacKenzie
d60e204e0a Use the same name everywhere for is_const_stable_const_fn 2020-09-22 10:05:58 -07:00
Dylan MacKenzie
3569bb6323 Update const-checker to replicate qualify_min_const_fn 2020-09-22 10:05:58 -07:00
Dylan MacKenzie
5ee5429e00 Add structured errors for qualify_min_const_fn checks 2020-09-22 10:05:58 -07:00
Dylan MacKenzie
bfc10a89c3 Allow errors to abort const checking when emitted
This is a hack for parity with `qualify_min_const_fn`, which only
emitted a single error.
2020-09-22 10:05:58 -07:00
Dylan MacKenzie
7fb9587a3c Return true if check_const emits an error 2020-09-22 10:05:58 -07:00
Dylan MacKenzie
a173c5c1b3 Add const-stability helpers 2020-09-22 10:05:58 -07:00
Dylan MacKenzie
3dd28c78c3 Useful derives on ops::Status 2020-09-22 10:05:58 -07:00
Ralf Jung
731113b8ee Miri: more informative deallocation error messages 2020-09-22 09:05:12 +02:00
ecstatic-morse
dcf4d1f2be
Rollup merge of #76888 - matthiaskrgr:clippy_single_match_2, r=Dylan-DPC
use if let instead of single match arm expressions

use if let instead of single match arm expressions to compact code and reduce nesting (clippy::single_match)
2020-09-21 20:40:55 -07:00
ecstatic-morse
60b99015e9
Rollup merge of #76807 - ecstatic-morse:const-checking-staged-api, r=oli-obk
Use const-checking to forbid use of unstable features in const-stable functions

First step towards #76618.

Currently this code isn't ever hit because `qualify_min_const_fn` runs first and catches pretty much everything. One exception is `const_precise_live_drops`, which does not use the newly added code since it runs as part of a separate pass.

Also contains some unrelated refactoring, which is split into separate commits.

r? @oli-obk
2020-09-21 20:40:53 -07:00
ecstatic-morse
30f1bab7e6
Rollup merge of #76581 - lcnr:bound-too-generic, r=eddyb
do not ICE on bound variables, return `TooGeneric` instead

fixes #73260, fixes #74634, fixes #76595

r? @nikomatsakis
2020-09-21 20:40:47 -07:00
Simon Vandel Sillesen
2bb3844820 Add optimization to avoid load of address 2020-09-21 22:08:27 +02:00
bors
e0bf356f9e Auto merge of #74040 - lcnr:const-occurs-check, r=nikomatsakis
fix unification of const variables

r? `@nikomatsakis` `@varkor` `@eddyb` let's just ping everyone here 😅
2020-09-21 12:52:09 +00:00
Bastian Kauschke
39245400c5 fix InterpCx resolve 2020-09-21 12:09:08 +02:00
yuk1ty
16047d46a1 fix typo in docs and comments 2020-09-21 12:14:28 +09:00
Kornel Lesiński
34d3c7df80 Let user see the full type of type-length limit error 2020-09-21 00:39:58 +01:00
bors
2e0edc0f28 Auto merge of #75119 - simonvandel:early-otherwise, r=oli-obk
New MIR optimization pass to reduce branches on match of tuples of enums

Fixes #68867 by adding a new pass that turns something like
```rust
let x: Option<()>;
let y: Option<()>;
match (x,y) {
    (Some(_), Some(_)) => {0},
    _ => {1}
}
```
into something like
```rust
let x: Option<()>;
let y: Option<()>;
let discriminant_x = // get discriminant of x
let discriminant_y = // get discriminant of x
if discriminant_x != discriminant_y {1} else {0}
```

The opt-diffs still have the old basic blocks like
```
bb3: {
          _8 = discriminant((*(_4.1: &ViewportPercentageLength))); // scope 0 at $DIR/early-otherwise-branch-68867.rs:21:21: 21:30
          switchInt(move _8) -> [1_isize: bb7, otherwise: bb2]; // scope 0 at $DIR/early-otherwise-branch-68867.rs:21:21: 21:30
      }

      bb4: {
          _9 = discriminant((*(_4.1: &ViewportPercentageLength))); // scope 0 at $DIR/early-otherwise-branch-68867.rs:22:23: 22:34
          switchInt(move _9) -> [2_isize: bb8, otherwise: bb2]; // scope 0 at $DIR/early-otherwise-branch-68867.rs:22:23: 22:34
      }

      bb5: {
          _10 = discriminant((*(_4.1: &ViewportPercentageLength))); // scope 0 at $DIR/early-otherwise-branch-68867.rs:23:23: 23:34
          switchInt(move _10) -> [3_isize: bb9, otherwise: bb2]; // scope 0 at $DIR/early-otherwise-branch-68867.rs:23:23: 23:34
      }
```

These do get removed on later passes. I'm not sure if I should include those passes in the test to make it clear?
2020-09-20 17:54:44 +00:00
Lzu Tao
4387480dea Add unstably const support for assume intrinsic 2020-09-20 14:00:40 +00:00
Ralf Jung
8405d50e12
Rollup merge of #76890 - matthiaskrgr:matches_simpl, r=lcnr
use matches!() macro for simple if let conditions
2020-09-20 15:52:01 +02:00
Lzu Tao
3e08354fb0 Correct file path after some restructures in compiler 2020-09-20 13:48:16 +00:00
Simon Vandel Sillesen
e25738f529 enable on mir-opt-level=1 to test perf 2020-09-20 14:45:47 +02:00
Simon Vandel Sillesen
27068cbfdc add cleanup of cfg 2020-09-20 14:45:47 +02:00
Simon Vandel Sillesen
118aae2af1 insert storageDead for not equal temp 2020-09-20 14:45:47 +02:00
Simon Vandel Sillesen
2530274023 correct comment 2020-09-20 14:45:46 +02:00
Simon Vandel Sillesen
5cc93950ac Update src/librustc_mir/transform/early_otherwise_branch.rs
Co-authored-by: Laurențiu Nicola <lnicola@users.noreply.github.com>
2020-09-20 14:45:46 +02:00
Simon Vandel Sillesen
5fb32c2e33 New MIR optimization pass to reduce branches on match of tuples of enums 2020-09-20 14:45:46 +02:00
Oliver Scherer
b2532a8730 Implement destructuring for all aggregates and for references 2020-09-20 13:28:18 +02:00
bors
41507ed0d5 Auto merge of #76964 - RalfJung:rollup-ybn06fs, r=RalfJung
Rollup of 15 pull requests

Successful merges:

 - #76722 (Test and fix Send and Sync traits of BTreeMap artefacts)
 - #76766 (Extract some intrinsics out of rustc_codegen_llvm)
 - #76800 (Don't generate bootstrap usage unless it's needed)
 - #76809 (simplfy condition in ItemLowerer::with_trait_impl_ref())
 - #76815 (Fix wording in mir doc)
 - #76818 (Don't compile regex at every function call.)
 - #76821 (Remove redundant nightly features)
 - #76823 (black_box: silence unused_mut warning when building with cfg(miri))
 - #76825 (use `array_windows` instead of `windows` in the compiler)
 - #76827 (fix array_windows docs)
 - #76828 (use strip_prefix over starts_with and manual slicing based on pattern length (clippy::manual_strip))
 - #76840 (Move to intra doc links in core/src/future)
 - #76845 (Use intra docs links in core::{ascii, option, str, pattern, hash::map})
 - #76853 (Use intra-doc links in library/core/src/task/wake.rs)
 - #76871 (support panic=abort in Miri)

Failed merges:

r? `@ghost`
2020-09-20 11:02:36 +00:00
Oliver Scherer
34c62e0abc Add a query for dereferencing constants of reference type 2020-09-20 12:42:44 +02:00
Ralf Jung
bfa1904765
Rollup merge of #76828 - matthiaskrgr:clippy_manual_strip, r=lcnr
use strip_prefix over starts_with and manual slicing based on pattern length (clippy::manual_strip)
2020-09-20 12:08:29 +02:00
Ralf Jung
50d56bc774
Rollup merge of #76825 - lcnr:array-windows-apply, r=varkor
use `array_windows` instead of `windows` in the compiler

I do think these changes are beautiful, but do have to admit that using type inference for the window length
can easily be confusing. This seems like a general issue with const generics, where inferring constants adds an additional
complexity which users have to learn and keep in mind.
2020-09-20 12:08:26 +02:00
Ralf Jung
4322e1b92d
Rollup merge of #76821 - est31:remove_redundant_nightly_features, r=oli-obk,Mark-Simulacrum
Remove redundant nightly features

Removes a bunch of redundant/outdated nightly features. The first commit removes a `core_intrinsics` use for which a stable wrapper has been provided since. The second commit replaces the `const_generics` feature with `min_const_generics` which might get stabilized this year. The third commit is the result of a trial/error run of removing every single feature and then adding it back if compile failed. A bunch of unused features are the result that the third commit removes.
2020-09-20 12:08:22 +02:00
Ralf Jung
3268e33199
Rollup merge of #76818 - hbina:dont_compile_regex_all_the_time, r=ecstatic-morse
Don't compile regex at every function call.

Use `SyncOnceCell` to only compile it once.
I believe this still adds some kind of locking mechanism?

Related issue: https://github.com/rust-lang/rust/issues/76817
2020-09-20 12:08:20 +02:00
Matthias Krüger
c690c82ad4 use if let instead of single match arm expressions to compact code and reduce nesting (clippy::single_match) 2020-09-20 11:42:52 +02:00
bors
5e449b9adf Auto merge of #74949 - oli-obk:validate_const_eval_raw, r=RalfJung
Validate constants during `const_eval_raw`

This PR implements the groundwork for https://github.com/rust-lang/rust/issues/72396

* constants are now validated during `const_eval_raw`
* to prevent cycle errors, we do not validate references to statics anymore beyond the fact that they are not dangling
* the `const_eval` query ICEs if used on `static` items
* as a side effect promoteds are now evaluated to `ConstValue::Scalar` again (since they are just a reference to the actual promoted allocation in most cases).
2020-09-20 08:58:32 +00:00
Bastian Kauschke
2a00dda902 miri: correctly deal with ConstKind::Bound 2020-09-20 08:22:35 +02:00
bors
10b3595ba6 Auto merge of #76411 - RalfJung:promote-in-const-fn, r=ecstatic-morse
Some promotion cleanup

Based on top of both https://github.com/rust-lang/rust/pull/75502 and https://github.com/rust-lang/rust/pull/75585, this does some cleanup of the promotion code. The last 2 commits are new.

* Remove the remaining cases where `const fn` is treated different from `fn`. This means no longer promoting ptr-to-int casts, raw ptr operations, and union field accesses in `const fn` -- or anywhere, for that matter. These are all unstable in const-context so this should not break any stable code. Fixes https://github.com/rust-lang/rust/issues/75586.
* ~~Promote references to statics even outside statics (i.e., in functions) for consistency.~~
* Promote `&mut []` everywhere, not just in non-`const` functions, for consistency.
* Explain why we do not promote deref's of statics outside statics. ~~(This is the only remaining direct user of `const_kind`.)~~

This can only land once the other two PRs land; I am mostly putting this up already because I couldn't wait ;) and to get some feedback from `@rust-lang/wg-const-eval` .
2020-09-20 06:20:16 +00:00
Bastian Kauschke
3435683fd5 use array_windows instead of windows in the compiler 2020-09-20 08:11:05 +02:00
bors
a3bc0e752f Auto merge of #75346 - davidtwco:issue-69925-polymorphic-instancedef-fnptrshim, r=nikomatsakis
shim: monomorphic `FnPtrShim`s during construction

Fixes #69925.

This PR adjusts MIR shim construction so that substitutions are applied to function pointer shims during construction, rather than during codegen (as determined by `substs_for_mir_body`).

r? `@eddyb`
2020-09-20 04:15:43 +00:00
bors
255a4c58f5 Auto merge of #72632 - jonas-schievink:dest-prop, r=oli-obk
Implement a generic Destination Propagation optimization on MIR

This takes the work that was originally started by `@eddyb` in https://github.com/rust-lang/rust/pull/47954, and then explored by me in https://github.com/rust-lang/rust/pull/71003, and implements it in a general (ie. not limited to acyclic CFGs) and dataflow-driven way (so that no additional infrastructure in rustc is needed).

The pass is configured to run at `mir-opt-level=2` and higher only. To enable it by default, some followup work on it is still needed:
* Performance needs to be evaluated. I did some light optimization work and tested against `tuple-stress`, which caused trouble in my last attempt, but didn't go much in depth here.
  * We can also enable the pass only at `opt-level=2` and higher, if it is too slow to run in debug mode, but fine when optimizations run anyways.
* Debuginfo needs to be fixed after locals are merged. I did not look into what is required for this.
* Live ranges of locals (aka `StorageLive` and `StorageDead`) are currently deleted. We either need to decide that this is fine, or if not, merge the variable's live ranges (or remove these statements entirely – https://github.com/rust-lang/rust/issues/68622).

Some benchmarks of the pass were done in https://github.com/rust-lang/rust/pull/72635.
2020-09-20 01:38:26 +00:00
Simon Vandel Sillesen
a875c7a1ea Add assertion for len of vecs 2020-09-19 23:22:54 +02:00
Ralf Jung
9216eb8258 fix some comments 2020-09-19 22:14:17 +02:00
Ralf Jung
7b99c8e1cf never promote non-const operations; revert STATIC promotion change 2020-09-19 22:14:17 +02:00
Ralf Jung
7febd5a257 fix doc comment 2020-09-19 22:14:17 +02:00
Ralf Jung
4d1ef03c9e cleanup promotion const_kind checks
in particular allow a few more promotions for consistency when they were already allowed in other contexts
2020-09-19 22:14:17 +02:00
Simon Vandel Sillesen
738ed9b5ec Fix #76803
Check that the variant index matches the target value from the SwitchInt we came from
2020-09-19 15:40:15 +02:00
Ralf Jung
4831523ac4
Rollup merge of #76757 - matthiaskrgr:clippy_try_into, r=lcnr
don't convert types to the same type with try_into (clippy::useless_conversion)
2020-09-19 11:47:52 +02:00
Ralf Jung
f62ba52f5c
Rollup merge of #75502 - ecstatic-morse:implicit-promotion-in-const-fn, r=RalfJung
Use implicit (not explicit) rules for promotability by default in `const fn`

For crater run. See https://github.com/rust-lang/const-eval/pull/54#discussion_r469995552.

cc #75586
2020-09-19 11:47:35 +02:00
Oliver Scherer
b8e6883a2f Reflect the "do not call this query directly" mentality in its name 2020-09-19 10:57:14 +02:00
Oliver Scherer
c3c8c981a8 Rustfmt 2020-09-19 10:36:36 +02:00
Oliver Scherer
182ed8544d Address review comments 2020-09-19 10:36:36 +02:00
Oliver Scherer
888afd50d9 Unify the names of const eval queries and their return types 2020-09-19 10:36:36 +02:00
Oliver Scherer
69a6be73e6 Rename const eval queries to reflect the validation changes 2020-09-19 10:36:36 +02:00
Oliver Scherer
dd9702a059 Do not call the const_eval query in mir interpretation except for caching of nulary intrinsics 2020-09-19 10:36:36 +02:00
Oliver Scherer
48f366fced Replace and_then map_err and_then chain with a match 2020-09-19 10:36:36 +02:00
Oliver Scherer
b1bd34df0c turn_into_const is infallible 2020-09-19 10:36:36 +02:00
Oliver Scherer
4397d66d42 Document op_to_const's purpose 2020-09-19 10:36:36 +02:00
Oliver Scherer
2d7ac728e4 Stop using the const_eval query for initializers of statics
As a side effect, we now represent most promoteds as `ConstValue::Scalar` again. This is useful because all implict promoteds are just references anyway and most explicit promoteds are numeric arguments to `asm!` or SIMD instructions.
2020-09-19 10:36:36 +02:00
Oliver Scherer
083f1d7a37 Validate constants during const_eval_raw 2020-09-19 10:36:36 +02:00
Jonas Schievink
2f9271b14c Clarify FIXME 2020-09-18 21:23:01 +02:00
Jonas Schievink
ffd9445812 Return Place by value 2020-09-18 21:23:01 +02:00
Jonas Schievink
682de94e31 Move inner items outside 2020-09-18 21:23:01 +02:00
Jonas Schievink
cd5d7201ad Fix rebase fallout 2020-09-18 21:23:01 +02:00
Jonas Schievink
7af964fecf Limit block count 2020-09-18 21:23:01 +02:00
Jonas Schievink
5728834448 Fix rebase fallout 2020-09-18 21:23:01 +02:00
Jonas Schievink
484db5b08a Properly inherit conflicts when merging locals 2020-09-18 21:23:01 +02:00
Jonas Schievink
934634eacc More logging 2020-09-18 21:23:01 +02:00
Jonas Schievink
88538adf9a Record intra-statement/terminator conflicts
Some MIR statements and terminators have an (undocumented...) invariant
that some of their input and outputs must not overlap. This records
conflicts between locals used in these positions.
2020-09-18 21:23:01 +02:00
Jonas Schievink
ddd6930b54 perf: bail out when there's >500 candidate locals 2020-09-18 21:23:01 +02:00
Jonas Schievink
ab26fb140c perf: only calculate conflicts for candidates 2020-09-18 21:23:01 +02:00
Jonas Schievink
402f863d8a perf: walk liveness backwards in Conflicts::build 2020-09-18 21:23:00 +02:00
Jonas Schievink
812d4bbc8d Fix dataflow assert errors 2020-09-18 21:23:00 +02:00
Jonas Schievink
78ff69ba10 Implement a destination propagation pass 2020-09-18 21:23:00 +02:00
Matthias Krüger
40dddd3305 use matches!() macro for simple if let conditions 2020-09-18 20:28:35 +02:00
bors
9f8ac718f4 Auto merge of #76575 - lcnr:abstract-const, r=oli-obk
compare generic constants using `AbstractConst`s

This is a MVP of rust-lang/compiler-team#340. The changes in this PR should only be relevant if `feature(const_evaluatable_checked)` is enabled.

~~currently based on top of #76559, so blocked on that.~~

r? `@oli-obk` cc `@varkor` `@eddyb`
2020-09-18 16:59:50 +00:00
Bastian Kauschke
d327fa112b initial working state 2020-09-18 16:25:25 +02:00
bors
fdc3405c20 Auto merge of #72412 - VFLashM:issue-72408-nested-closures-exponential, r=tmandry
Issue 72408 nested closures exponential

This fixes #72408.

Nested closures were resulting in exponential compilation time.

This PR is enhancing asymptotic complexity, but also increasing the constant, so I would love to see perf run results.
2020-09-18 14:08:39 +00:00
bors
2c69266c06 Auto merge of #76837 - wesleywiser:disable_consideredequal, r=oli-obk
[mir-opt] Disable the `ConsideredEqual` logic in SimplifyBranchSame opt

The logic is currently broken and we need to disable it to fix a beta
regression (see #76803)

r? `@oli-obk`
2020-09-18 10:54:14 +00:00
Valerii Lashmanov
17d2e3b5d2 Better handling for exponential-sized types in misc places
Mostly to fix ui/issues/issue-37311-type-length-limit/issue-37311.rs.

Most parts of the compiler can handle deeply nested types with a lot
of duplicates just fine, but some parts still attempt to naively
traverse type tree.

Before such problems were caught by type length limit check,
but now these places will have to be changed to handle
duplicated types gracefully.
2020-09-17 20:44:11 -05:00
Dylan MacKenzie
e03f4164d9 Default to implicit (not explicit) rules for promotability in const fn 2020-09-17 08:39:11 -07:00
Wesley Wiser
dbd7226d29 [mir-opt] Disable the ConsideredEqual logic in SimplifyBranchSame opt
The logic is currently broken and we need to disable it to fix a beta
regression (see #76803)
2020-09-17 09:36:50 -04:00
bors
7bdb5dee7b Auto merge of #76634 - RalfJung:miri-guaranteed-eq-ne, r=oli-obk
move guaranteed{ne,eq} implementation to compile-time machine

Currently, Miri needs a special hack to avoid using the core engine implementation of these intrinsics. That seems silly, so let's move them to the CTFE machine, which is the only machine that wants to use them.

I also added a reference to https://github.com/rust-lang/rust/issues/73722 as a warning to anyone who wants to adjust `guaranteed_eq`.
2020-09-17 12:15:57 +00:00
Matthias Krüger
012974da7a use strip_prefix over starts_with and manual slicing based on pattern length (clippy::manual_strip) 2020-09-17 10:13:16 +02:00
est31
ebdea01143 Remove redundant #![feature(...)] 's from compiler/ 2020-09-17 07:58:45 +02:00
Hanif Bin Ariffin
f4a7149f49 Don't compile regex at every function call.
Use `SyncOnceCell` to only compile it once.
I believe this still adds some kind of locking mechanism?
2020-09-17 11:03:08 +08:00
Matthias Krüger
0e3414248a don't lazily evaulate some trivial values for Option::None replacements (clippy::unnecessary_lazy_evaluations) 2020-09-17 01:37:35 +02:00
Dylan MacKenzie
81b3b66487 Error if an unstable const eval feature is used in a stable const fn 2020-09-16 14:17:51 -07:00
Dylan MacKenzie
e4edc161f2 Give name to extra Span in LiveDrop error 2020-09-16 14:17:51 -07:00
Dylan MacKenzie
c3607bd7dd Use helper function for searching allow_internal_unstable 2020-09-16 14:17:51 -07:00
Dylan MacKenzie
ed6c7efd87 Use enum for status of non-const ops 2020-09-16 14:17:51 -07:00
Tyler Mandry
3bf66ae25f
Rollup merge of #76794 - richkadel:graphviz-font, r=ecstatic-morse
Make graphviz font configurable

Alternative to PR #76776.

To change the graphviz output to use an alternative `fontname` value,
add a command line option like: `rustc --graphviz-font=monospace`.

r? @ecstatic-morse
2020-09-16 12:24:30 -07:00
Tyler Mandry
cd766c9d09
Rollup merge of #76775 - ecstatic-morse:dataflow-extra-tab-diff, r=Mark-Simulacrum
Strip a single leading tab when rendering dataflow diffs

The `fmt_diff_with` formatter uses a tab to separate additions from subtractions. Strip it when rendering those diffs on separate lines.

r? @Mark-Simulacrum (since you're speedy)
2020-09-16 12:24:27 -07:00
Tyler Mandry
a6c4d30c7b
Rollup merge of #76756 - matthiaskrgr:cl123ppy, r=Dylan-DPC
fix a couple of stylistic clippy warnings

namely:

clippy::redundant_pattern_matching
clippy::redundant_pattern
clippy::search_is_some
clippy::filter_next
clippy::into_iter_on_ref
clippy::clone_on_copy
clippy::needless_return
2020-09-16 12:24:17 -07:00
Rich Kadel
5c29332ace Make graphviz font configurable
Alternative to PR ##76776.

To change the graphviz output to use an alternative `fontname` value,
add a command line option like: `rustc --graphviz-font=monospace`.
2020-09-16 08:10:06 -07:00
Dylan DPC
2c2f1c239e
Rollup merge of #76694 - wesleywiser:partitioning_cx_trait, r=davidtwco
Introduce a PartitioningCx struct

This contains all the data used by the partitioning algorithm and allows that data to be used at each stage of the partitioning. This is useful for other approaches to partitioning which may want different pieces of the data available at each step.

cc @rust-lang/wg-incr-comp
2020-09-16 12:34:18 +02:00
Dylan MacKenzie
c910e038e8 Strip a single leading tab when rendering dataflow diffs 2020-09-15 18:32:12 -07:00
Tomasz Miąsko
ff1a9e406b Fix underflow when calculating the number of no-op jumps folded
When removing unwinds to no-op blocks and folding jumps to no-op blocks,
remove the unwind target first. Otherwise we cannot determine if target
has been already folded or not.

Previous implementation incorrectly assumed that all resume targets had
been folded already, occasionally resulting in an underflow:

remove_noop_landing_pads: removed 18446744073709551613 jumps and 3 landing pads
2020-09-16 00:00:00 +00:00
Dylan DPC
fa4cfeb597
Rollup merge of #75304 - Aaron1011:feature/diag-deref-move-out, r=estebank
Note when a a move/borrow error is caused by a deref coercion

Fixes #73268

When a deref coercion occurs, we may end up with a move error if the
base value has been partially moved out of. However, we do not indicate
anywhere that a deref coercion is occuring, resulting in an error
message with a confusing span.

This PR adds an explicit note to move errors when a deref coercion is
involved. We mention the name of the type that the deref-coercion
resolved to, as well as the `Deref::Target` associated type being used.
2020-09-16 01:30:32 +02:00
Matthias Krüger
f567287f9f don't convert types to the same type with try_into (clippy::useless_conversion) 2020-09-15 22:49:50 +02:00
Matthias Krüger
73d4171ea6 fix a couple of stylistic clippy warnings
namely:

clippy::redundant_pattern_matching
clippy::redundant_pattern
clippy::search_is_some
clippy::filter_next
clippy::into_iter_on_ref
clippy::clone_on_copy
clippy::needless_return
2020-09-15 22:44:54 +02:00
Dylan MacKenzie
0475c365fe Add pass names to some common dataflow analyses 2020-09-14 17:56:39 -07:00
Dylan MacKenzie
8e3ce43de9 Add Engine::pass_name to differentiate dataflow runs 2020-09-14 17:56:21 -07:00
bors
9b4154193e Auto merge of #76541 - matthiaskrgr:unstable_sort, r=davidtwco
use sort_unstable to sort primitive types

It's not important to retain original order if we have &[1, 1, 2, 3] for example.

clippy::stable_sort_primitive
2020-09-14 21:43:17 +00:00
bors
0b65a3d0a6 Auto merge of #76123 - tmiasko:inline-args-storage, r=wesleywiser
inliner: Emit storage markers for introduced arg temporaries

When introducing argument temporaries during inlining, emit storage
marker statements just before the assignment and in the beginning of
the return block.

This ensures that such temporaries will not be considered live across
yield points after inlining inside a generator.

Fixes #71793.
2020-09-14 02:13:02 +00:00
Wesley Wiser
c9686cb31a Introduce a PartitioningCx struct 2020-09-13 21:08:08 -04:00
bors
7402a39447 Auto merge of #76244 - vandenheuvel:remove__paramenv__def_id, r=nikomatsakis
Removing the `def_id` field from hot `ParamEnv` to make it smaller

This PR addresses https://github.com/rust-lang/rust/issues/74865.
2020-09-13 16:28:22 +00:00
Simon Vandel Sillesen
e5447a2222 Fix #76432
Only insert StorageDeads if we actually removed one.
Fixes an issue where we added StorageDead to a place with no StorageLive
2020-09-13 10:47:20 +02:00
bors
498dab0256 Auto merge of #76306 - tmiasko:nrvo-debuginfo, r=ecstatic-morse
NRVO: Allow occurrences of the return place in var debug info

The non-use occurrence of the return place in var debug info does not
currently inhibit NRVO optimization, but it will fail assertion in
`visit_place` when optimization is performed.

Relax assertion check to allow the return place in var debug info.

This case might be impossible to hit in optimization pipelines as of
now, but can be encountered in customized mir-opt-level=2 pipeline with
copy propagation disabled. For example in:

```rust
pub fn b(s: String) -> String {
    a(s)
}

#[inline]
pub fn a(s: String) -> String {
    let x = s;
    let y = x;
    y
}
```
2020-09-13 00:33:04 +00:00
Ralf Jung
c32127675a move guaranteed{ne,eq} implementation to compile-time machine 2020-09-12 10:10:52 +02:00
Andreas Jonson
b8752fff19 update the version of itertools and parking_lot
this is to avoid compiling multiple version of the crates in rustc
2020-09-12 08:26:53 +02:00
Aaron Hill
d18b4bb7a7
Note when a a move/borrow error is caused by a deref coercion
Fixes #73268

When a deref coercion occurs, we may end up with a move error if the
base value has been partially moved out of. However, we do not indicate
anywhere that a deref coercion is occuring, resulting in an error
message with a confusing span.

This PR adds an explicit note to move errors when a deref coercion is
involved. We mention the name of the type that the deref-coercion
resolved to, as well as the `Deref::Target` associated type being used.
2020-09-10 20:56:20 -04:00
Tyler Mandry
c8f9c728c2
Rollup merge of #76567 - matthiaskrgr:clone_on_copy, r=varkor
use push(char) to add chars (single-char &strs) to strings instead of push_str(&str)
2020-09-10 12:20:12 -07:00
Tyler Mandry
94ae5d1866
Rollup merge of #76565 - matthiaskrgr:box_place, r=oli-obk
take reference to Place directly instead of taking reference to Box<Place>

clippy::borrowed_box
2020-09-10 12:20:11 -07:00
Tyler Mandry
2df1487fc9
Rollup merge of #76548 - tmiasko:validate, r=davidtwco
Validate removal of AscribeUserType, FakeRead, and Shallow borrow

Those statements are removed by CleanupNonCodegenStatements pass
in drop lowering phase, and should not occur afterwards.
2020-09-10 12:20:04 -07:00
Matthias Krüger
9bb10cc907 use push(char) instead of push_str(&str) to add single chars to strings
clippy::single-char-push-str
2020-09-10 13:58:41 +02:00
Matthias Krüger
e2a511fe20 use String::from instead of format!() macro to craft string clippy::useless_format 2020-09-10 13:22:51 +02:00
Matthias Krüger
6bfe132067 take reference to Place directly instead of taking reference to Box<Place>
clippy::borrowed_box
2020-09-10 13:08:28 +02:00
bors
88197214b8 Auto merge of #75573 - Aaron1011:feature/const-mutation-lint, r=oli-obk
Add CONST_ITEM_MUTATION lint

Fixes #74053
Fixes #55721

This PR adds a new lint `CONST_ITEM_MUTATION`.
Given an item `const FOO: SomeType = ..`, this lint fires on:

* Attempting to write directly to a field (`FOO.field = some_val`) or
  array entry (`FOO.array_field[0] = val`)
* Taking a mutable reference to the `const` item (`&mut FOO`), including
  through an autoderef `FOO.some_mut_self_method()`

The lint message explains that since each use of a constant creates a
new temporary, the original `const` item will not be modified.
2020-09-10 05:54:26 +00:00
Tyler Mandry
ba6e2b3a31
Rollup merge of #76500 - richkadel:mir-graphviz-dark, r=tmandry
Add -Zgraphviz_dark_mode and monospace font fix

Many developers use a dark theme with editors and IDEs, but this
typically doesn't extend to graphviz output.

When I bring up a MIR graphviz document, the white background is
strikingly bright. This new option changes the colors used for graphviz
output to work better in dark-themed UIs.

<img width="1305" alt="Screen Shot 2020-09-09 at 3 00 31 PM" src="https://user-images.githubusercontent.com/3827298/92659478-4b9bff00-f2ad-11ea-8894-b40d3a873cb9.png">

Also fixed the monospace font for common graphviz renders (e.g., VS Code extensions), as described in https://github.com/rust-lang/rust/pull/76500#issuecomment-689837948

**Before:**
<img width="943" alt="Screen Shot 2020-09-09 at 2 48 44 PM" src="https://user-images.githubusercontent.com/3827298/92658939-47231680-f2ac-11ea-97ac-96727e4dd622.png">

**Now with fix:**
<img width="943" alt="Screen Shot 2020-09-09 at 2 49 02 PM" src="https://user-images.githubusercontent.com/3827298/92658959-51451500-f2ac-11ea-9aae-de982d466d6a.png">
2020-09-09 21:02:35 -07:00
Tomasz Miąsko
00e64ba476 Validate removal of AscribeUserType, FakeRead, and Shallow borrow
Those statements are removed by CleanupNonCodegenStatements pass
in drop lowering phase, and should not occur afterwards.
2020-09-10 00:00:00 +00:00
Tyler Mandry
32714eb6bc
Rollup merge of #76523 - tmiasko:non-use-context-coverage, r=wesleywiser
Remove unused PlaceContext::NonUse(NonUseContext::Coverage)

r? @richkadel / @wesleywiser
2020-09-09 15:06:07 -07:00
Tyler Mandry
bab09684b4
Rollup merge of #76313 - richkadel:mir-spanview-2, r=wesleywiser
Improved the MIR spanview output

* Adds missing "tail" spans (spans that continue beyond the end of
overlapping spans)
* Adds a caret to highlight empty spans associated with MIR elements
that have a position, but otherwise would not be visible.
* Adds visual pointing brackets at the beginning and end of each span

<img width="590" alt="Screen Shot 2020-09-03 at 8 38 08 PM" src="https://user-images.githubusercontent.com/3827298/92202571-25510c00-ee34-11ea-89bc-89eea939476d.png">
<img width="1061" alt="Screen Shot 2020-09-03 at 8 41 04 PM" src="https://user-images.githubusercontent.com/3827298/92202629-49145200-ee34-11ea-8fda-fc6e62c80736.png">
<img width="1113" alt="Screen Shot 2020-09-06 at 5 42 57 PM" src="https://user-images.githubusercontent.com/3827298/92339198-ca085f00-f069-11ea-96d1-c01ced50e2ba.png">
<img width="1692" alt="Screen Shot 2020-09-06 at 5 45 54 PM" src="https://user-images.githubusercontent.com/3827298/92339209-d4c2f400-f069-11ea-94c0-b4d36c200878.png">

r? @tmandry
FYI: @wesleywiser
2020-09-09 15:05:49 -07:00
Matthias Krüger
b4935e0726 use sort_unstable to sort primitive types
It's not important to retain original order if we have &[1, 1, 2, 3] for example.

clippy::stable_sort_primitive
2020-09-10 00:03:58 +02:00
Rich Kadel
f7aee330c7 Also fixed monospace font for d3-graphviz engine
VS code graphviz extensions use d3-graphviz, which supports `Courier`
fontname but does not support `monospace`. This caused graphs to render
poorly because the text sizes were wrong.
2020-09-09 14:49:32 -07:00
Tomasz Miąsko
0016405073 Remove unused PlaceContext::NonUse(NonUseContext::Coverage) 2020-09-09 17:02:19 +02:00
Bram van den Heuvel
7dad29d686 Remove def_id field from ParamEnv 2020-09-09 10:14:31 +02:00
Rich Kadel
c19b2370e4 Add -Zgraphviz_dark_mode
Many developers use a dark theme with editors and IDEs, but this
typically doesn't extend to graphviz output.

When I bring up a MIR graphviz document, the white background is
strikingly bright. This new option changes the colors used for graphviz
output to work better in dark-themed UIs.
2020-09-08 17:19:38 -07:00
bors
5a6b426e34 Auto merge of #76308 - wesleywiser:enable_simplifyarmidentity_mir_opt, r=oli-obk
Enable the SimplifyArmIdentity MIR optimization at mir-opt-level=1

r? `@ghost`
2020-09-08 09:27:23 +00:00
bors
e82584a77d Auto merge of #75585 - RalfJung:demotion, r=oli-obk
Do not promote &mut of a non-ZST ever

Since ~pre-1.0~ 1.36, we have accepted code like this:
```rust
static mut TEST: &'static mut [i32] = {
    let x = &mut [1,2,3];
    x
};
```
I tracked it back to https://github.com/rust-lang/rust/pull/21744, but unfortunately could not find any discussion or RFC that would explain why we thought this was a good idea. And it's not, it breaks all sorts of things -- see https://github.com/rust-lang/rust/issues/75556.

To fix https://github.com/rust-lang/rust/issues/75556, we have to stop promoting non-ZST mutable references no matter the context, which is what this PR does. It's a breaking change.

Notice that this still works, since it does not rely on promotion:
```rust
static mut TEST: &'static mut [i32] = &mut [0,1,2];
```

Cc `@rust-lang/wg-const-eval`
2020-09-08 05:13:42 +00:00
bors
0e2c1281e9 Auto merge of #76044 - ecstatic-morse:dataflow-lattice, r=oli-obk
Support dataflow problems on arbitrary lattices

This PR implements last of the proposed extensions I mentioned in the design meeting for the original dataflow refactor. It extends the current dataflow framework to work with arbitrary lattices, not just `BitSet`s. This is a prerequisite for dataflow-enabled MIR const-propagation. Personally, I am skeptical of the usefulness of doing const-propagation pre-monomorphization, since many useful constants only become known after monomorphization (e.g. `size_of::<T>()`) and users have a natural tendency to hand-optimize the rest. It's probably worth exprimenting with, however, and others have shown interest cc `@rust-lang/wg-mir-opt.`

The `Idx` associated type is moved from `AnalysisDomain` to `GenKillAnalysis` and replaced with an associated `Domain` type that must implement `JoinSemiLattice`. Like before, each `Analysis` defines the "bottom value" for its domain, but can no longer override the dataflow join operator. Analyses that want to use set intersection must now use the `lattice::Dual` newtype. `GenKillAnalysis` impls have an additional requirement that `Self::Domain: BorrowMut<BitSet<Self::Idx>>`, which effectively means that they must use `BitSet<Self::Idx>` or `lattice::Dual<BitSet<Self::Idx>>` as their domain.

Most of these changes were mechanical. However, because a `Domain` is no longer always a powerset of some index type, we can no longer use an `IndexVec<BasicBlock, GenKillSet<A::Idx>>>` to store cached block transfer functions. Instead, we use a boxed `dyn Fn` trait object. I discuss a few alternatives to the current approach in a commit message.

The majority of new lines of code are to preserve existing Graphviz diagrams for those unlucky enough to have to debug dataflow analyses. I find these diagrams incredibly useful when things are going wrong and considered regressing them unacceptable, especially the pretty-printing of `MovePathIndex`s, which are used in many dataflow analyses. This required a parallel `fmt` trait used only for printing dataflow domains, as well as a refactoring of the `graphviz` module now that we cannot expect the domain to be a `BitSet`. Some features did have to be removed, such as the gen/kill display mode (which I didn't use but existed to mirror the output of the old dataflow framework) and line wrapping. Since I had to rewrite much of it anyway, I took the opportunity to switch to a `Visitor` for printing dataflow state diffs instead of using cursors, which are error prone for code that must be generic over both forward and backward analyses. As a side-effect of this change, we no longer have quadratic behavior when writing graphviz diagrams for backward dataflow analyses.

r? `@pnkfelix`
2020-09-07 21:29:43 +00:00
Aaron Hill
f422ef141a
Add CONST_ITEM_MUTATION lint
Fixes #74053
Fixes #55721

This PR adds a new lint `CONST_ITEM_MUTATION`.
Given an item `const FOO: SomeType = ..`, this lint fires on:

* Attempting to write directly to a field (`FOO.field = some_val`) or
  array entry (`FOO.array_field[0] = val`)
* Taking a mutable reference to the `const` item (`&mut FOO`), including
  through an autoderef `FOO.some_mut_self_method()`

The lint message explains that since each use of a constant creates a
new temporary, the original `const` item will not be modified.
2020-09-07 08:44:35 -04:00
Rich Kadel
9046a9343b Improved the MIR spanview output
* Adds missing "tail" spans (spans that continue beyond the end of
overlapping spans)
* Adds a caret to highlight empty spans associated with MIR elements
that have a position, but otherwise would not be visible.
* Adds visual pointing brackets at the beginning and end of each span
2020-09-06 19:04:08 -07:00
Ralf Jung
720293b640 do not premote non-ZST mutable references ever 2020-09-06 14:14:27 +02:00
Simon Vandel Sillesen
9b0fc6202b Generalize to Eq(true, _place) and Eq(_place, true) 2020-09-06 11:51:44 +02:00
Simon Vandel Sillesen
c2693db264 Add peephold optimization that simplifies Ne(_1, false) and Ne(false, _1) into _1
This was observed emitted from the MatchBranchSimplification pass.
2020-09-06 11:51:44 +02:00
Dylan DPC
b4d3873024
Rollup merge of #76263 - tmiasko:inline-codegen-fn-attrs, r=ecstatic-morse
inliner: Check for codegen fn attributes compatibility

* Check for target features compatibility
* Check for no_sanitize attribute compatibility

Fixes #76259.
2020-09-05 16:28:34 +02:00
LeSeulArtichaut
3e14b684dd Change ty.kind to a method 2020-09-04 17:47:51 +02:00
David Wood
f8376b59d1
shim: monomorphic FnPtrShims during construction
This commit adjusts MIR shim construction so that substitutions are
applied to function pointer shims during construction, rather than
during codegen (as determined by `substs_for_mir_body`) - as
substitutions will no longer occur during codegen, function pointer
shims can now be polymorphic without incurring double substitutions.

Signed-off-by: David Wood <david@davidtw.co>
2020-09-04 13:00:49 +01:00
bors
4ffb5c5954 Auto merge of #76004 - richkadel:llvm-coverage-map-gen-6b.5, r=tmandry
Tools, tests, and experimenting with MIR-derived coverage counters

Leverages the new mir_dump output file in HTML+CSS (from #76074) to visualize coverage code regions
and the MIR features that they came from (including overlapping spans).

See example below.

The `run-make-fulldeps/instrument-coverage` test has been refactored to maximize test coverage and reduce code duplication. The new tests support testing with and without `-Clink-dead-code`, so Rust coverage can be tested on MSVC (which, currently, only works with `link-dead-code` _disabled_).

New tests validate coverage region generation and coverage reports with multiple counters per function. Starting with a simple `if-else` branch tests, coverage tests for each additional syntax type can be added by simply dropping in a new Rust sample program.

Includes a basic, MIR-block-based implementation of coverage injection,
available via `-Zexperimental-coverage`. This implementation has known
flaws and omissions, but is simple enough to validate the new tools and
tests.

The existing `-Zinstrument-coverage` option currently enables
function-level coverage only, which at least appears to generate
accurate coverage reports at that level.

Experimental coverage is not accurate at this time. When branch coverage
works as intended, the `-Zexperimental-coverage` option should be
removed.

This PR replaces the bulk of PR #75828, with the remaining parts of
that PR distributed among other separate and indentpent PRs.

This PR depends on two of those other PRs: #76002, #76003 and #76074

Rust compiler MCP rust-lang/compiler-team#278

Relevant issue: #34701 - Implement support for LLVMs code coverage
instrumentation

![Screen-Recording-2020-08-21-at-2](https://user-images.githubusercontent.com/3827298/90972923-ff417880-e4d1-11ea-92bb-8713c6198f6d.gif)

r? @tmandry
FYI: @wesleywiser
2020-09-04 01:31:07 +00:00