Auto merge of #108116 - Dylan-DPC:rollup-h3n2vxl, r=Dylan-DPC

Rollup of 6 pull requests

Successful merges:

 - #106372 (Use id-based thread parking on SOLID)
 - #108050 (Fix index out of bounds ICE in `point_at_expr_source_of_inferred_type`)
 - #108084 (Constify `RangeBounds`, `RangeX::contains` and `RangeX::is_empty` (where applicable).)
 - #108101 (don't clone types that are copy)
 - #108102 (simplify some refs)
 - #108103 (be nice and don't slice)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
This commit is contained in:
bors 2023-02-16 07:15:13 +00:00
commit 4b34c7b766
17 changed files with 174 additions and 234 deletions

View File

@ -1970,7 +1970,7 @@ pub fn associated_path_to_ty(
) = &qself.kind {
// If the path segment already has type params, we want to overwrite
// them.
match &path.segments[..] {
match &path.segments {
// `segment` is the previous to last element on the path,
// which would normally be the `enum` itself, while the last
// `_` `PathSegment` corresponds to the variant.
@ -2670,7 +2670,7 @@ pub fn res_to_ty(
// `Self` in trait or type alias.
assert_eq!(opt_self_ty, None);
self.prohibit_generics(path.segments.iter(), |err| {
if let [hir::PathSegment { args: Some(args), ident, .. }] = &path.segments[..] {
if let [hir::PathSegment { args: Some(args), ident, .. }] = &path.segments {
err.span_suggestion_verbose(
ident.span.shrink_to_hi().to(args.span_ext),
"the `Self` type doesn't accept type parameters",

View File

@ -298,6 +298,12 @@ fn visit_expr(&mut self, ex: &'v hir::Expr<'v>) {
// call's arguments and we can provide a more explicit span.
let sig = self.tcx.fn_sig(def_id).subst_identity();
let def_self_ty = sig.input(0).skip_binder();
let param_tys = sig.inputs().skip_binder().iter().skip(1);
// If there's an arity mismatch, pointing out the call as the source of an inference
// can be misleading, so we skip it.
if param_tys.len() != args.len() {
continue;
}
let rcvr_ty = self.node_ty(rcvr.hir_id);
// Get the evaluated type *after* calling the method call, so that the influence
// of the arguments can be reflected in the receiver type. The receiver
@ -323,13 +329,12 @@ fn visit_expr(&mut self, ex: &'v hir::Expr<'v>) {
let mut param_found = FxHashMap::default();
if self.can_eq(self.param_env, ty, found) {
// We only point at the first place where the found type was inferred.
for (i, param_ty) in sig.inputs().skip_binder().iter().skip(1).enumerate() {
for (param_ty, arg) in param_tys.zip(args) {
if def_self_ty.contains(*param_ty) && let ty::Param(_) = param_ty.kind() {
// We found an argument that references a type parameter in `Self`,
// so we assume that this is the argument that caused the found
// type, which we know already because of `can_eq` above was first
// inferred in this method call.
let arg = &args[i];
let arg_ty = self.node_ty(arg.hir_id);
if !arg.span.overlaps(mismatch_span) {
err.span_label(

View File

@ -517,8 +517,7 @@ fn method_autoderef_steps<'tcx>(
.by_ref()
.map(|(ty, d)| {
let step = CandidateStep {
self_ty: infcx
.make_query_response_ignoring_pending_obligations(inference_vars.clone(), ty),
self_ty: infcx.make_query_response_ignoring_pending_obligations(inference_vars, ty),
autoderefs: d,
from_unsafe_deref: reached_raw_pointer,
unsize: false,

View File

@ -125,7 +125,7 @@ fn add_kind(&mut self, kind: &ty::TyKind<'_>) {
self.bound_computation(ts, |flags, ts| flags.add_tys(ts));
}
&ty::GeneratorWitnessMIR(_, ref substs) => {
ty::GeneratorWitnessMIR(_, substs) => {
let should_remove_further_specializable =
!self.flags.contains(TypeFlags::STILL_FURTHER_SPECIALIZABLE);
self.add_substs(substs);

View File

@ -92,7 +92,7 @@ fn complete(&self, key: K, value: V, index: DepNodeIndex) -> Self::Stored {
let mut lock = self.cache.lock();
// We may be overwriting another value. This is all right, since the dep-graph
// will check that the fingerprint matches.
lock.insert(key, (value.clone(), index));
lock.insert(key, (value, index));
value
}
@ -153,7 +153,7 @@ fn lookup(&self, _key: &()) -> Option<(V, DepNodeIndex)> {
#[inline]
fn complete(&self, _key: (), value: V, index: DepNodeIndex) -> Self::Stored {
*self.cache.lock() = Some((value.clone(), index));
*self.cache.lock() = Some((value, index));
value
}
@ -283,7 +283,7 @@ fn complete(&self, key: K, value: V, index: DepNodeIndex) -> Self::Stored {
let mut lock = self.cache.get_shard_by_hash(key.index() as u64).lock();
#[cfg(not(parallel_compiler))]
let mut lock = self.cache.lock();
lock.insert(key, (value.clone(), index));
lock.insert(key, (value, index));
value
}

View File

@ -547,7 +547,7 @@ fn try_merge_responses(
response.value.certainty == Certainty::Yes
&& response.has_no_inference_or_external_constraints()
}) {
return Ok(response.clone());
return Ok(*response);
}
let certainty = candidates.iter().fold(Certainty::AMBIGUOUS, |certainty, response| {

View File

@ -599,7 +599,7 @@ fn virtual_call_violation_for_method<'tcx>(
return false;
}
contains_illegal_self_type_reference(tcx, trait_def_id, pred.clone())
contains_illegal_self_type_reference(tcx, trait_def_id, pred)
}) {
return Some(MethodViolationCode::WhereClauseReferencesSelf);
}

View File

@ -336,7 +336,7 @@ fn eq(&self, other: &TyKind<I>) -> bool {
a_d == b_d && a_s == b_s && a_m == b_m
}
(GeneratorWitness(a_g), GeneratorWitness(b_g)) => a_g == b_g,
(&GeneratorWitnessMIR(ref a_d, ref a_s), &GeneratorWitnessMIR(ref b_d, ref b_s)) => {
(GeneratorWitnessMIR(a_d, a_s), GeneratorWitnessMIR(b_d, b_s)) => {
a_d == b_d && a_s == b_s
}
(Tuple(a_t), Tuple(b_t)) => a_t == b_t,
@ -397,8 +397,8 @@ fn cmp(&self, other: &TyKind<I>) -> Ordering {
}
(GeneratorWitness(a_g), GeneratorWitness(b_g)) => a_g.cmp(b_g),
(
&GeneratorWitnessMIR(ref a_d, ref a_s),
&GeneratorWitnessMIR(ref b_d, ref b_s),
GeneratorWitnessMIR(a_d, a_s),
GeneratorWitnessMIR(b_d, b_s),
) => match Ord::cmp(a_d, b_d) {
Ordering::Equal => Ord::cmp(a_s, b_s),
cmp => cmp,

View File

@ -1491,9 +1491,10 @@ fn ne(&self, other: &&B) -> bool {
}
}
#[stable(feature = "rust1", since = "1.0.0")]
impl<A: ?Sized, B: ?Sized> PartialOrd<&B> for &A
#[rustc_const_unstable(feature = "const_cmp", issue = "92391")]
impl<A: ?Sized, B: ?Sized> const PartialOrd<&B> for &A
where
A: PartialOrd<B>,
A: ~const PartialOrd<B>,
{
#[inline]
fn partial_cmp(&self, other: &&B) -> Option<Ordering> {

View File

@ -96,7 +96,7 @@ fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
}
}
impl<Idx: PartialOrd<Idx>> Range<Idx> {
impl<Idx: ~const PartialOrd<Idx>> Range<Idx> {
/// Returns `true` if `item` is contained in the range.
///
/// # Examples
@ -116,10 +116,11 @@ impl<Idx: PartialOrd<Idx>> Range<Idx> {
/// assert!(!(f32::NAN..1.0).contains(&0.5));
/// ```
#[stable(feature = "range_contains", since = "1.35.0")]
pub fn contains<U>(&self, item: &U) -> bool
#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")]
pub const fn contains<U>(&self, item: &U) -> bool
where
Idx: PartialOrd<U>,
U: ?Sized + PartialOrd<Idx>,
Idx: ~const PartialOrd<U>,
U: ?Sized + ~const PartialOrd<Idx>,
{
<Self as RangeBounds<Idx>>::contains(self, item)
}
@ -142,7 +143,8 @@ pub fn contains<U>(&self, item: &U) -> bool
/// assert!( (f32::NAN..5.0).is_empty());
/// ```
#[stable(feature = "range_is_empty", since = "1.47.0")]
pub fn is_empty(&self) -> bool {
#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")]
pub const fn is_empty(&self) -> bool {
!(self.start < self.end)
}
}
@ -199,7 +201,7 @@ fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
}
}
impl<Idx: PartialOrd<Idx>> RangeFrom<Idx> {
impl<Idx: ~const PartialOrd<Idx>> RangeFrom<Idx> {
/// Returns `true` if `item` is contained in the range.
///
/// # Examples
@ -214,10 +216,11 @@ impl<Idx: PartialOrd<Idx>> RangeFrom<Idx> {
/// assert!(!(f32::NAN..).contains(&0.5));
/// ```
#[stable(feature = "range_contains", since = "1.35.0")]
pub fn contains<U>(&self, item: &U) -> bool
#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")]
pub const fn contains<U>(&self, item: &U) -> bool
where
Idx: PartialOrd<U>,
U: ?Sized + PartialOrd<Idx>,
Idx: ~const PartialOrd<U>,
U: ?Sized + ~const PartialOrd<Idx>,
{
<Self as RangeBounds<Idx>>::contains(self, item)
}
@ -280,7 +283,7 @@ fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
}
}
impl<Idx: PartialOrd<Idx>> RangeTo<Idx> {
impl<Idx: ~const PartialOrd<Idx>> RangeTo<Idx> {
/// Returns `true` if `item` is contained in the range.
///
/// # Examples
@ -295,10 +298,11 @@ impl<Idx: PartialOrd<Idx>> RangeTo<Idx> {
/// assert!(!(..f32::NAN).contains(&0.5));
/// ```
#[stable(feature = "range_contains", since = "1.35.0")]
pub fn contains<U>(&self, item: &U) -> bool
#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")]
pub const fn contains<U>(&self, item: &U) -> bool
where
Idx: PartialOrd<U>,
U: ?Sized + PartialOrd<Idx>,
Idx: ~const PartialOrd<U>,
U: ?Sized + ~const PartialOrd<Idx>,
{
<Self as RangeBounds<Idx>>::contains(self, item)
}
@ -437,7 +441,8 @@ pub const fn end(&self) -> &Idx {
/// ```
#[stable(feature = "inclusive_range_methods", since = "1.27.0")]
#[inline]
pub fn into_inner(self) -> (Idx, Idx) {
#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")]
pub const fn into_inner(self) -> (Idx, Idx) {
(self.start, self.end)
}
}
@ -469,7 +474,7 @@ fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
}
}
impl<Idx: PartialOrd<Idx>> RangeInclusive<Idx> {
impl<Idx: ~const PartialOrd<Idx>> RangeInclusive<Idx> {
/// Returns `true` if `item` is contained in the range.
///
/// # Examples
@ -500,10 +505,11 @@ impl<Idx: PartialOrd<Idx>> RangeInclusive<Idx> {
/// assert!(!r.contains(&3) && !r.contains(&5));
/// ```
#[stable(feature = "range_contains", since = "1.35.0")]
pub fn contains<U>(&self, item: &U) -> bool
#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")]
pub const fn contains<U>(&self, item: &U) -> bool
where
Idx: PartialOrd<U>,
U: ?Sized + PartialOrd<Idx>,
Idx: ~const PartialOrd<U>,
U: ?Sized + ~const PartialOrd<Idx>,
{
<Self as RangeBounds<Idx>>::contains(self, item)
}
@ -535,8 +541,9 @@ pub fn contains<U>(&self, item: &U) -> bool
/// assert!(r.is_empty());
/// ```
#[stable(feature = "range_is_empty", since = "1.47.0")]
#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")]
#[inline]
pub fn is_empty(&self) -> bool {
pub const fn is_empty(&self) -> bool {
self.exhausted || !(self.start <= self.end)
}
}
@ -598,7 +605,7 @@ fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
}
}
impl<Idx: PartialOrd<Idx>> RangeToInclusive<Idx> {
impl<Idx: ~const PartialOrd<Idx>> RangeToInclusive<Idx> {
/// Returns `true` if `item` is contained in the range.
///
/// # Examples
@ -613,10 +620,11 @@ impl<Idx: PartialOrd<Idx>> RangeToInclusive<Idx> {
/// assert!(!(..=f32::NAN).contains(&0.5));
/// ```
#[stable(feature = "range_contains", since = "1.35.0")]
pub fn contains<U>(&self, item: &U) -> bool
#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")]
pub const fn contains<U>(&self, item: &U) -> bool
where
Idx: PartialOrd<U>,
U: ?Sized + PartialOrd<Idx>,
Idx: ~const PartialOrd<U>,
U: ?Sized + ~const PartialOrd<Idx>,
{
<Self as RangeBounds<Idx>>::contains(self, item)
}
@ -757,6 +765,7 @@ pub fn cloned(self) -> Bound<T> {
/// `RangeBounds` is implemented by Rust's built-in range types, produced
/// by range syntax like `..`, `a..`, `..b`, `..=c`, `d..e`, or `f..=g`.
#[stable(feature = "collections_range", since = "1.28.0")]
#[const_trait]
pub trait RangeBounds<T: ?Sized> {
/// Start index bound.
///
@ -809,8 +818,8 @@ pub trait RangeBounds<T: ?Sized> {
#[stable(feature = "range_contains", since = "1.35.0")]
fn contains<U>(&self, item: &U) -> bool
where
T: PartialOrd<U>,
U: ?Sized + PartialOrd<T>,
T: ~const PartialOrd<U>,
U: ?Sized + ~const PartialOrd<T>,
{
(match self.start_bound() {
Included(start) => start <= item,
@ -827,7 +836,8 @@ fn contains<U>(&self, item: &U) -> bool
use self::Bound::{Excluded, Included, Unbounded};
#[stable(feature = "collections_range", since = "1.28.0")]
impl<T: ?Sized> RangeBounds<T> for RangeFull {
#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")]
impl<T: ?Sized> const RangeBounds<T> for RangeFull {
fn start_bound(&self) -> Bound<&T> {
Unbounded
}
@ -837,7 +847,8 @@ fn end_bound(&self) -> Bound<&T> {
}
#[stable(feature = "collections_range", since = "1.28.0")]
impl<T> RangeBounds<T> for RangeFrom<T> {
#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")]
impl<T> const RangeBounds<T> for RangeFrom<T> {
fn start_bound(&self) -> Bound<&T> {
Included(&self.start)
}
@ -847,7 +858,8 @@ fn end_bound(&self) -> Bound<&T> {
}
#[stable(feature = "collections_range", since = "1.28.0")]
impl<T> RangeBounds<T> for RangeTo<T> {
#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")]
impl<T> const RangeBounds<T> for RangeTo<T> {
fn start_bound(&self) -> Bound<&T> {
Unbounded
}
@ -857,7 +869,8 @@ fn end_bound(&self) -> Bound<&T> {
}
#[stable(feature = "collections_range", since = "1.28.0")]
impl<T> RangeBounds<T> for Range<T> {
#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")]
impl<T> const RangeBounds<T> for Range<T> {
fn start_bound(&self) -> Bound<&T> {
Included(&self.start)
}
@ -867,7 +880,8 @@ fn end_bound(&self) -> Bound<&T> {
}
#[stable(feature = "collections_range", since = "1.28.0")]
impl<T> RangeBounds<T> for RangeInclusive<T> {
#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")]
impl<T> const RangeBounds<T> for RangeInclusive<T> {
fn start_bound(&self) -> Bound<&T> {
Included(&self.start)
}
@ -883,7 +897,8 @@ fn end_bound(&self) -> Bound<&T> {
}
#[stable(feature = "collections_range", since = "1.28.0")]
impl<T> RangeBounds<T> for RangeToInclusive<T> {
#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")]
impl<T> const RangeBounds<T> for RangeToInclusive<T> {
fn start_bound(&self) -> Bound<&T> {
Unbounded
}
@ -893,7 +908,8 @@ fn end_bound(&self) -> Bound<&T> {
}
#[stable(feature = "collections_range", since = "1.28.0")]
impl<T> RangeBounds<T> for (Bound<T>, Bound<T>) {
#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")]
impl<T> const RangeBounds<T> for (Bound<T>, Bound<T>) {
fn start_bound(&self) -> Bound<&T> {
match *self {
(Included(ref start), _) => Included(start),
@ -912,7 +928,8 @@ fn end_bound(&self) -> Bound<&T> {
}
#[stable(feature = "collections_range", since = "1.28.0")]
impl<'a, T: ?Sized + 'a> RangeBounds<T> for (Bound<&'a T>, Bound<&'a T>) {
#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")]
impl<'a, T: ?Sized + 'a> const RangeBounds<T> for (Bound<&'a T>, Bound<&'a T>) {
fn start_bound(&self) -> Bound<&T> {
self.0
}
@ -923,7 +940,8 @@ fn end_bound(&self) -> Bound<&T> {
}
#[stable(feature = "collections_range", since = "1.28.0")]
impl<T> RangeBounds<T> for RangeFrom<&T> {
#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")]
impl<T> const RangeBounds<T> for RangeFrom<&T> {
fn start_bound(&self) -> Bound<&T> {
Included(self.start)
}
@ -933,7 +951,8 @@ fn end_bound(&self) -> Bound<&T> {
}
#[stable(feature = "collections_range", since = "1.28.0")]
impl<T> RangeBounds<T> for RangeTo<&T> {
#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")]
impl<T> const RangeBounds<T> for RangeTo<&T> {
fn start_bound(&self) -> Bound<&T> {
Unbounded
}
@ -943,7 +962,8 @@ fn end_bound(&self) -> Bound<&T> {
}
#[stable(feature = "collections_range", since = "1.28.0")]
impl<T> RangeBounds<T> for Range<&T> {
#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")]
impl<T> const RangeBounds<T> for Range<&T> {
fn start_bound(&self) -> Bound<&T> {
Included(self.start)
}
@ -953,7 +973,8 @@ fn end_bound(&self) -> Bound<&T> {
}
#[stable(feature = "collections_range", since = "1.28.0")]
impl<T> RangeBounds<T> for RangeInclusive<&T> {
#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")]
impl<T> const RangeBounds<T> for RangeInclusive<&T> {
fn start_bound(&self) -> Bound<&T> {
Included(self.start)
}
@ -963,7 +984,8 @@ fn end_bound(&self) -> Bound<&T> {
}
#[stable(feature = "collections_range", since = "1.28.0")]
impl<T> RangeBounds<T> for RangeToInclusive<&T> {
#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")]
impl<T> const RangeBounds<T> for RangeToInclusive<&T> {
fn start_bound(&self) -> Bound<&T> {
Unbounded
}

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@ -0,0 +1,37 @@
use super::abi;
use super::error::expect_success_aborting;
use super::time::with_tmos;
use crate::time::Duration;
pub type ThreadId = abi::ID;
pub use super::task::current_task_id_aborting as current;
pub fn park(_hint: usize) {
match unsafe { abi::slp_tsk() } {
abi::E_OK | abi::E_RLWAI => {}
err => {
expect_success_aborting(err, &"slp_tsk");
}
}
}
pub fn park_timeout(dur: Duration, _hint: usize) {
match with_tmos(dur, |tmo| unsafe { abi::tslp_tsk(tmo) }) {
abi::E_OK | abi::E_RLWAI | abi::E_TMOUT => {}
err => {
expect_success_aborting(err, &"tslp_tsk");
}
}
}
pub fn unpark(id: ThreadId, _hint: usize) {
match unsafe { abi::wup_tsk(id) } {
// It is allowed to try to wake up a destroyed or unrelated task, so we ignore all
// errors that could result from that situation.
abi::E_OK | abi::E_NOEXS | abi::E_OBJ | abi::E_QOVR => {}
err => {
expect_success_aborting(err, &"wup_tsk");
}
}
}

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@ -1,72 +0,0 @@
use crate::mem::MaybeUninit;
use crate::time::Duration;
use super::{
abi,
error::{expect_success, fail},
time::with_tmos,
};
const CLEAR: abi::FLGPTN = 0;
const RAISED: abi::FLGPTN = 1;
/// A thread parking primitive that is not susceptible to race conditions,
/// but provides no atomic ordering guarantees and allows only one `raise` per wait.
pub struct WaitFlag {
flag: abi::ID,
}
impl WaitFlag {
/// Creates a new wait flag.
pub fn new() -> WaitFlag {
let flag = expect_success(
unsafe {
abi::acre_flg(&abi::T_CFLG {
flgatr: abi::TA_FIFO | abi::TA_WSGL | abi::TA_CLR,
iflgptn: CLEAR,
})
},
&"acre_flg",
);
WaitFlag { flag }
}
/// Wait for the wait flag to be raised.
pub fn wait(&self) {
let mut token = MaybeUninit::uninit();
expect_success(
unsafe { abi::wai_flg(self.flag, RAISED, abi::TWF_ORW, token.as_mut_ptr()) },
&"wai_flg",
);
}
/// Wait for the wait flag to be raised or the timeout to occur.
///
/// Returns whether the flag was raised (`true`) or the operation timed out (`false`).
pub fn wait_timeout(&self, dur: Duration) -> bool {
let mut token = MaybeUninit::uninit();
let res = with_tmos(dur, |tmout| unsafe {
abi::twai_flg(self.flag, RAISED, abi::TWF_ORW, token.as_mut_ptr(), tmout)
});
match res {
abi::E_OK => true,
abi::E_TMOUT => false,
error => fail(error, &"twai_flg"),
}
}
/// Raise the wait flag.
///
/// Calls to this function should be balanced with the number of successful waits.
pub fn raise(&self) {
expect_success(unsafe { abi::set_flg(self.flag, RAISED) }, &"set_flg");
}
}
impl Drop for WaitFlag {
fn drop(&mut self) {
expect_success(unsafe { abi::del_flg(self.flag) }, &"del_flg");
}
}

View File

@ -13,9 +13,9 @@ mod itron {
pub(super) mod spin;
pub(super) mod task;
pub mod thread;
pub mod thread_parking;
pub(super) mod time;
use super::unsupported;
pub mod wait_flag;
}
pub mod alloc;
@ -43,8 +43,8 @@ mod itron {
pub mod memchr;
pub mod thread_local_dtor;
pub mod thread_local_key;
pub use self::itron::thread_parking;
pub mod time;
pub use self::itron::wait_flag;
mod rwlock;

View File

@ -14,12 +14,10 @@
} else if #[cfg(any(
target_os = "netbsd",
all(target_vendor = "fortanix", target_env = "sgx"),
target_os = "solid_asp3",
))] {
mod id;
pub use id::Parker;
} else if #[cfg(target_os = "solid_asp3")] {
mod wait_flag;
pub use wait_flag::Parker;
} else if #[cfg(any(windows, target_family = "unix"))] {
pub use crate::sys::thread_parking::Parker;
} else {

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@ -1,102 +0,0 @@
//! A wait-flag-based thread parker.
//!
//! Some operating systems provide low-level parking primitives like wait counts,
//! event flags or semaphores which are not susceptible to race conditions (meaning
//! the wakeup can occur before the wait operation). To implement the `std` thread
//! parker on top of these primitives, we only have to ensure that parking is fast
//! when the thread token is available, the atomic ordering guarantees are maintained
//! and spurious wakeups are minimized.
//!
//! To achieve this, this parker uses an atomic variable with three states: `EMPTY`,
//! `PARKED` and `NOTIFIED`:
//! * `EMPTY` means the token has not been made available, but the thread is not
//! currently waiting on it.
//! * `PARKED` means the token is not available and the thread is parked.
//! * `NOTIFIED` means the token is available.
//!
//! `park` and `park_timeout` change the state from `EMPTY` to `PARKED` and from
//! `NOTIFIED` to `EMPTY`. If the state was `NOTIFIED`, the thread was unparked and
//! execution can continue without calling into the OS. If the state was `EMPTY`,
//! the token is not available and the thread waits on the primitive (here called
//! "wait flag").
//!
//! `unpark` changes the state to `NOTIFIED`. If the state was `PARKED`, the thread
//! is or will be sleeping on the wait flag, so we raise it.
use crate::pin::Pin;
use crate::sync::atomic::AtomicI8;
use crate::sync::atomic::Ordering::{Acquire, Relaxed, Release};
use crate::sys::wait_flag::WaitFlag;
use crate::time::Duration;
const EMPTY: i8 = 0;
const PARKED: i8 = -1;
const NOTIFIED: i8 = 1;
pub struct Parker {
state: AtomicI8,
wait_flag: WaitFlag,
}
impl Parker {
/// Construct a parker for the current thread. The UNIX parker
/// implementation requires this to happen in-place.
pub unsafe fn new_in_place(parker: *mut Parker) {
parker.write(Parker { state: AtomicI8::new(EMPTY), wait_flag: WaitFlag::new() })
}
// This implementation doesn't require `unsafe` and `Pin`, but other implementations do.
pub unsafe fn park(self: Pin<&Self>) {
match self.state.fetch_sub(1, Acquire) {
// NOTIFIED => EMPTY
NOTIFIED => return,
// EMPTY => PARKED
EMPTY => (),
_ => panic!("inconsistent park state"),
}
// Avoid waking up from spurious wakeups (these are quite likely, see below).
loop {
self.wait_flag.wait();
match self.state.compare_exchange(NOTIFIED, EMPTY, Acquire, Relaxed) {
Ok(_) => return,
Err(PARKED) => (),
Err(_) => panic!("inconsistent park state"),
}
}
}
// This implementation doesn't require `unsafe` and `Pin`, but other implementations do.
pub unsafe fn park_timeout(self: Pin<&Self>, dur: Duration) {
match self.state.fetch_sub(1, Acquire) {
NOTIFIED => return,
EMPTY => (),
_ => panic!("inconsistent park state"),
}
self.wait_flag.wait_timeout(dur);
// Either a wakeup or a timeout occurred. Wakeups may be spurious, as there can be
// a race condition when `unpark` is performed between receiving the timeout and
// resetting the state, resulting in the eventflag being set unnecessarily. `park`
// is protected against this by looping until the token is actually given, but
// here we cannot easily tell.
// Use `swap` to provide acquire ordering.
match self.state.swap(EMPTY, Acquire) {
NOTIFIED => (),
PARKED => (),
_ => panic!("inconsistent park state"),
}
}
// This implementation doesn't require `Pin`, but other implementations do.
pub fn unpark(self: Pin<&Self>) {
let state = self.state.swap(NOTIFIED, Release);
if state == PARKED {
self.wait_flag.raise();
}
}
}

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struct S<A, B>(Option<(A, B)>);
impl<A, B> S<A, B> {
fn infer(&self, a: A, b: B) {}
//~^ NOTE associated function defined here
//~| NOTE
//~| NOTE
}
fn main() {
let s = S(None);
s.infer(0i32);
//~^ ERROR this method takes 2 arguments but 1 argument was supplied
//~| NOTE an argument is missing
//~| HELP provide the argument
let t: S<u32, _> = s;
//~^ ERROR mismatched types
//~| NOTE expected `S<u32, _>`, found `S<i32, _>`
//~| NOTE expected due to this
//~| NOTE expected struct `S<u32, _>`
}

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error[E0061]: this method takes 2 arguments but 1 argument was supplied
--> $DIR/point-at-inference-4.rs:12:7
|
LL | s.infer(0i32);
| ^^^^^------ an argument is missing
|
note: associated function defined here
--> $DIR/point-at-inference-4.rs:4:8
|
LL | fn infer(&self, a: A, b: B) {}
| ^^^^^ ---- ----
help: provide the argument
|
LL | s.infer(0i32, /* b */);
| ~~~~~~~~~~~~~~~
error[E0308]: mismatched types
--> $DIR/point-at-inference-4.rs:16:24
|
LL | let t: S<u32, _> = s;
| --------- ^ expected `S<u32, _>`, found `S<i32, _>`
| |
| expected due to this
|
= note: expected struct `S<u32, _>`
found struct `S<i32, _>`
error: aborting due to 2 previous errors
Some errors have detailed explanations: E0061, E0308.
For more information about an error, try `rustc --explain E0061`.