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Split non-CAS atomic support off into target_has_atomic_load_store #65214
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A small note on the code: in some places I do |
N.B. I wouldn't mind this as an internal refactoring but I don't think we should expose |
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r=me on the code changes here, although I'm travleing this week so I'm not abreast of the conversation happening in the thread. If it's reached consensus this is the way to go feel free to send it through bors! Otherwise I'll check in when I'm back next week to catch up on the thread |
@bors r=alexcrichton |
📌 Commit dfe76a1 has been approved by |
⌛ Testing commit dfe76a1 with merge e45bc382e7333fd3fcc3da15d147faaf89062ea7... |
Split non-CAS atomic support off into target_has_atomic_load_store This PR implements my proposed changes in rust-lang#32976 (comment) by removing `target_has_atomic = "cas"` and splitting `target_has_atomic` into two separate `cfg`s: * `target_has_atomic = 8/16/32/64/128`: This indicates the largest width that the target can atomically CAS (which implies support for all atomic operations). * ` target_has_atomic_load_store = 8/16/32/64/128`: This indicates the largest width that the target can support loading or storing atomically (but may not support CAS). cc rust-lang#32976 r? @alexcrichton
@bors retry rolled up. |
⌛ Testing commit dfe76a1 with merge 0c36b2a3c2faf937a78f91b104515ff4b79bd6a1... |
Split non-CAS atomic support off into target_has_atomic_load_store This PR implements my proposed changes in rust-lang#32976 (comment) by removing `target_has_atomic = "cas"` and splitting `target_has_atomic` into two separate `cfg`s: * `target_has_atomic = 8/16/32/64/128`: This indicates the largest width that the target can atomically CAS (which implies support for all atomic operations). * ` target_has_atomic_load_store = 8/16/32/64/128`: This indicates the largest width that the target can support loading or storing atomically (but may not support CAS). cc rust-lang#32976 r? @alexcrichton
@bors retry rolled up. |
Rollup of 10 pull requests Successful merges: - #65214 (Split non-CAS atomic support off into target_has_atomic_load_store) - #65246 (vxWorks: implement get_path() and get_mode() for File fmt::Debug) - #65312 (improve performance of signed saturating_mul) - #65336 (Fix typo in task::Waker) - #65346 (nounwind tests and cleanup) - #65347 (Fix #[unwind(abort)] with Rust ABI) - #65366 (Implement Error::source on IntoStringError + Remove superfluous cause impls) - #65369 (Don't discard value names when using address or memory sanitizer) - #65370 (Add `dyn` to `Any` documentation) - #65373 (Fix typo in docs for `Rc`) Failed merges: r? @ghost
428: Fix breakage with nightly feature r=jeehoonkang a=taiki-e `target_has_atomic = "cas"` was removed in rust-lang/rust#65214. Fixes rust-lang/rust#65424 Co-authored-by: Taiki Endo <[email protected]>
428: Fix breakage with nightly feature r=jeehoonkang a=taiki-e `target_has_atomic = "cas"` was removed in rust-lang/rust#65214. Fixes rust-lang/rust#65424 Fixes #412 Co-authored-by: Taiki Endo <[email protected]>
428: Fix build failure on nightly and the minimum version r=jeehoonkang a=taiki-e `target_has_atomic = "cas"` was removed in rust-lang/rust#65214. Fixes rust-lang/rust#65424 Fixes #412 Co-authored-by: Taiki Endo <[email protected]>
428: Fix build failure on nightly and the minimum version r=jeehoonkang a=taiki-e `target_has_atomic = "cas"` was removed in rust-lang/rust#65214. Fixes rust-lang/rust#65424 Fixes #412 Co-authored-by: Taiki Endo <[email protected]>
#[stable(feature = "unwind_safe_atomic_refs", since = "1.14.0")] | ||
impl RefUnwindSafe for atomic::AtomicUsize {} | ||
#[cfg(target_has_atomic = "8")] | ||
#[cfg(target_hastarget_has_atomic_load_store_atomic = "8")] |
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copypaste error?
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Oops #65663
Rollup of 7 pull requests Successful merges: - #62330 (Change untagged_unions to not allow union fields with drop) - #65092 (make is_power_of_two a const function) - #65621 (miri: add write_bytes method to Memory doing bounds-checks and supporting iterators) - #65647 (Remove unnecessary trait bounds and derivations) - #65653 (keep the root dir clean from debugging) - #65660 (Rename `ConstValue::Infer(InferConst::Canonical(..))` to `ConstValue::Bound(..)`) - #65663 (Fix typo from #65214) Failed merges: r? @ghost
16: Update crossbeam-epoch requirement from 0.7.0 to 0.8.0 r=bossmc a=dependabot-preview[bot] Updates the requirements on [crossbeam-epoch](https://github.com/crossbeam-rs/crossbeam) to permit the latest version. <details> <summary>Changelog</summary> *Sourced from [crossbeam-epoch's changelog](https://github.com/crossbeam-rs/crossbeam/blob/master/CHANGELOG.md).* > # Version 0.7.3 > > - Fix breakage with nightly feature due to [rust-lang/rust#65214](https://github-redirect.dependabot.com/rust-lang/rust/issues/65214). > - Bump `crossbeam-channel` to `0.4`. > - Bump `crossbeam-epoch` to `0.8`. > - Bump `crossbeam-queue` to `0.2`. > - Bump `crossbeam-utils` to `0.7`. > > # Version 0.7.2 > > - Bump `crossbeam-channel` to `0.3.9`. > - Bump `crossbeam-epoch` to `0.7.2`. > - Bump `crossbeam-utils` to `0.6.6`. > > # Version 0.7.1 > > - Bump `crossbeam-utils` to `0.6.5`. > > # Version 0.7.0 > > - Remove `ArcCell`, `MsQueue`, and `TreiberStack`. > - Change the interface of `ShardedLock` to match `RwLock`. > - Add `SegQueue::len()`. > - Rename `SegQueue::try_pop()` to `SegQueue::pop()`. > - Change the return type of `SegQueue::pop()` to `Result`. > - Introduce `ArrayQueue`. > - Update dependencies. > > # Version 0.6.0 > > - Update dependencies. > > # Version 0.5.0 > > - Update `crossbeam-channel` to 0.3. > - Update `crossbeam-utils` to 0.6. > - Add `AtomicCell`, `SharedLock`, and `WaitGroup`. > > # Version 0.4.1 > > - Fix a double-free bug in `MsQueue` and `SegQueue`. > > # Version 0.4 > > - Switch to the new implementation of epoch-based reclamation in > [`crossbeam-epoch`](https://github.com/crossbeam-rs/crossbeam-epoch), fixing numerous bugs in the > old implementation. Its API is changed in a backward-incompatible way. > - Switch to the new implementation of `CachePadded` and scoped thread in > [`crossbeam-utils`](https://github.com/crossbeam-rs/crossbeam-utils). The scoped thread API is > changed in a backward-incompatible way. ></tr></table> ... (truncated) </details> <details> <summary>Commits</summary> - [`28ad2b7`](crossbeam-rs/crossbeam@28ad2b7) Update versions in readmes - [`c98fea1`](crossbeam-rs/crossbeam@c98fea1) Merge [#444](https://github-redirect.dependabot.com/crossbeam-rs/crossbeam/issues/444) - [`d953f49`](crossbeam-rs/crossbeam@d953f49) Add compatibility section to readme - [`c76f145`](crossbeam-rs/crossbeam@c76f145) Prepare for the next release - [`99762ee`](crossbeam-rs/crossbeam@99762ee) Merge [#442](https://github-redirect.dependabot.com/crossbeam-rs/crossbeam/issues/442) - [`ebb6b5f`](crossbeam-rs/crossbeam@ebb6b5f) Do not perform superfluous bounds checks on drop - [`d2ab7a5`](crossbeam-rs/crossbeam@d2ab7a5) Update LICENSE-APACHE - [`f54db88`](crossbeam-rs/crossbeam@f54db88) Merge [#437](https://github-redirect.dependabot.com/crossbeam-rs/crossbeam/issues/437) - [`caa52c4`](crossbeam-rs/crossbeam@caa52c4) Merge [#436](https://github-redirect.dependabot.com/crossbeam-rs/crossbeam/issues/436) - [`af68803`](crossbeam-rs/crossbeam@af68803) Merge [#438](https://github-redirect.dependabot.com/crossbeam-rs/crossbeam/issues/438) - Additional commits viewable in [compare view](crossbeam-rs/crossbeam@crossbeam-epoch-0.7.0...crossbeam-epoch-0.8.0) </details> <br /> Dependabot will resolve any conflicts with this PR as long as you don't alter it yourself. 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155: Bump crossbeam-channel from 0.3.9 to 0.4.0 r=pitkley a=dependabot-preview[bot] [//]: # (dependabot-start)⚠️ **Dependabot is rebasing this PR**⚠️ If you make any changes to it yourself then they will take precedence over the rebase. --- [//]: # (dependabot-end) Bumps [crossbeam-channel](https://github.com/crossbeam-rs/crossbeam) from 0.3.9 to 0.4.0. <details> <summary>Changelog</summary> *Sourced from [crossbeam-channel's changelog](https://github.com/crossbeam-rs/crossbeam/blob/master/CHANGELOG.md).* > # Version 0.7.3 > > - Fix breakage with nightly feature due to [rust-lang/rust#65214](https://github-redirect.dependabot.com/rust-lang/rust/issues/65214). > - Bump `crossbeam-channel` to `0.4`. > - Bump `crossbeam-epoch` to `0.8`. > - Bump `crossbeam-queue` to `0.2`. > - Bump `crossbeam-utils` to `0.7`. > > # Version 0.7.2 > > - Bump `crossbeam-channel` to `0.3.9`. > - Bump `crossbeam-epoch` to `0.7.2`. > - Bump `crossbeam-utils` to `0.6.6`. > > # Version 0.7.1 > > - Bump `crossbeam-utils` to `0.6.5`. > > # Version 0.7.0 > > - Remove `ArcCell`, `MsQueue`, and `TreiberStack`. > - Change the interface of `ShardedLock` to match `RwLock`. > - Add `SegQueue::len()`. > - Rename `SegQueue::try_pop()` to `SegQueue::pop()`. > - Change the return type of `SegQueue::pop()` to `Result`. > - Introduce `ArrayQueue`. > - Update dependencies. > > # Version 0.6.0 > > - Update dependencies. > > # Version 0.5.0 > > - Update `crossbeam-channel` to 0.3. > - Update `crossbeam-utils` to 0.6. > - Add `AtomicCell`, `SharedLock`, and `WaitGroup`. > > # Version 0.4.1 > > - Fix a double-free bug in `MsQueue` and `SegQueue`. > > # Version 0.4 > > - Switch to the new implementation of epoch-based reclamation in > [`crossbeam-epoch`](https://github.com/crossbeam-rs/crossbeam-epoch), fixing numerous bugs in the > old implementation. Its API is changed in a backward-incompatible way. > - Switch to the new implementation of `CachePadded` and scoped thread in > [`crossbeam-utils`](https://github.com/crossbeam-rs/crossbeam-utils). The scoped thread API is > changed in a backward-incompatible way. ></tr></table> ... (truncated) </details> <details> <summary>Commits</summary> - [`28ad2b7`](crossbeam-rs/crossbeam@28ad2b7) Update versions in readmes - [`c98fea1`](crossbeam-rs/crossbeam@c98fea1) Merge [#444](https://github-redirect.dependabot.com/crossbeam-rs/crossbeam/issues/444) - [`d953f49`](crossbeam-rs/crossbeam@d953f49) Add compatibility section to readme - [`c76f145`](crossbeam-rs/crossbeam@c76f145) Prepare for the next release - [`99762ee`](crossbeam-rs/crossbeam@99762ee) Merge [#442](https://github-redirect.dependabot.com/crossbeam-rs/crossbeam/issues/442) - [`ebb6b5f`](crossbeam-rs/crossbeam@ebb6b5f) Do not perform superfluous bounds checks on drop - [`d2ab7a5`](crossbeam-rs/crossbeam@d2ab7a5) Update LICENSE-APACHE - [`f54db88`](crossbeam-rs/crossbeam@f54db88) Merge [#437](https://github-redirect.dependabot.com/crossbeam-rs/crossbeam/issues/437) - [`caa52c4`](crossbeam-rs/crossbeam@caa52c4) Merge [#436](https://github-redirect.dependabot.com/crossbeam-rs/crossbeam/issues/436) - [`af68803`](crossbeam-rs/crossbeam@af68803) Merge [#438](https://github-redirect.dependabot.com/crossbeam-rs/crossbeam/issues/438) - Additional commits viewable in [compare view](crossbeam-rs/crossbeam@crossbeam-channel-0.3.9...crossbeam-channel-0.4.0) </details> <br /> [![Dependabot compatibility score](https://api.dependabot.com/badges/compatibility_score?dependency-name=crossbeam-channel&package-manager=cargo&previous-version=0.3.9&new-version=0.4.0)](https://dependabot.com/compatibility-score.html?dependency-name=crossbeam-channel&package-manager=cargo&previous-version=0.3.9&new-version=0.4.0) Dependabot will resolve any conflicts with this PR as long as you don't alter it yourself. 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155: Bump crossbeam-channel from 0.3.9 to 0.4.0 r=pitkley a=dependabot-preview[bot] Bumps [crossbeam-channel](https://github.com/crossbeam-rs/crossbeam) from 0.3.9 to 0.4.0. <details> <summary>Changelog</summary> *Sourced from [crossbeam-channel's changelog](https://github.com/crossbeam-rs/crossbeam/blob/master/CHANGELOG.md).* > # Version 0.7.3 > > - Fix breakage with nightly feature due to [rust-lang/rust#65214](https://github-redirect.dependabot.com/rust-lang/rust/issues/65214). > - Bump `crossbeam-channel` to `0.4`. > - Bump `crossbeam-epoch` to `0.8`. > - Bump `crossbeam-queue` to `0.2`. > - Bump `crossbeam-utils` to `0.7`. > > # Version 0.7.2 > > - Bump `crossbeam-channel` to `0.3.9`. > - Bump `crossbeam-epoch` to `0.7.2`. > - Bump `crossbeam-utils` to `0.6.6`. > > # Version 0.7.1 > > - Bump `crossbeam-utils` to `0.6.5`. > > # Version 0.7.0 > > - Remove `ArcCell`, `MsQueue`, and `TreiberStack`. > - Change the interface of `ShardedLock` to match `RwLock`. > - Add `SegQueue::len()`. > - Rename `SegQueue::try_pop()` to `SegQueue::pop()`. > - Change the return type of `SegQueue::pop()` to `Result`. > - Introduce `ArrayQueue`. > - Update dependencies. > > # Version 0.6.0 > > - Update dependencies. > > # Version 0.5.0 > > - Update `crossbeam-channel` to 0.3. > - Update `crossbeam-utils` to 0.6. > - Add `AtomicCell`, `SharedLock`, and `WaitGroup`. > > # Version 0.4.1 > > - Fix a double-free bug in `MsQueue` and `SegQueue`. > > # Version 0.4 > > - Switch to the new implementation of epoch-based reclamation in > [`crossbeam-epoch`](https://github.com/crossbeam-rs/crossbeam-epoch), fixing numerous bugs in the > old implementation. Its API is changed in a backward-incompatible way. > - Switch to the new implementation of `CachePadded` and scoped thread in > [`crossbeam-utils`](https://github.com/crossbeam-rs/crossbeam-utils). The scoped thread API is > changed in a backward-incompatible way. ></tr></table> ... (truncated) </details> <details> <summary>Commits</summary> - [`28ad2b7`](crossbeam-rs/crossbeam@28ad2b7) Update versions in readmes - [`c98fea1`](crossbeam-rs/crossbeam@c98fea1) Merge [#444](https://github-redirect.dependabot.com/crossbeam-rs/crossbeam/issues/444) - [`d953f49`](crossbeam-rs/crossbeam@d953f49) Add compatibility section to readme - [`c76f145`](crossbeam-rs/crossbeam@c76f145) Prepare for the next release - [`99762ee`](crossbeam-rs/crossbeam@99762ee) Merge [#442](https://github-redirect.dependabot.com/crossbeam-rs/crossbeam/issues/442) - [`ebb6b5f`](crossbeam-rs/crossbeam@ebb6b5f) Do not perform superfluous bounds checks on drop - [`d2ab7a5`](crossbeam-rs/crossbeam@d2ab7a5) Update LICENSE-APACHE - [`f54db88`](crossbeam-rs/crossbeam@f54db88) Merge [#437](https://github-redirect.dependabot.com/crossbeam-rs/crossbeam/issues/437) - [`caa52c4`](crossbeam-rs/crossbeam@caa52c4) Merge [#436](https://github-redirect.dependabot.com/crossbeam-rs/crossbeam/issues/436) - [`af68803`](crossbeam-rs/crossbeam@af68803) Merge [#438](https://github-redirect.dependabot.com/crossbeam-rs/crossbeam/issues/438) - Additional commits viewable in [compare view](crossbeam-rs/crossbeam@crossbeam-channel-0.3.9...crossbeam-channel-0.4.0) </details> <br /> [![Dependabot compatibility score](https://api.dependabot.com/badges/compatibility_score?dependency-name=crossbeam-channel&package-manager=cargo&previous-version=0.3.9&new-version=0.4.0)](https://dependabot.com/compatibility-score.html?dependency-name=crossbeam-channel&package-manager=cargo&previous-version=0.3.9&new-version=0.4.0) Dependabot will resolve any conflicts with this PR as long as you don't alter it yourself. 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Profiler: reenable atomics after rust-lang#65214
This PR implements my proposed changes in #32976 (comment) by removing
target_has_atomic = "cas"
and splittingtarget_has_atomic
into two separatecfg
s:target_has_atomic = 8/16/32/64/128
: This indicates the largest width that the target can atomically CAS (which implies support for all atomic operations).target_has_atomic_load_store = 8/16/32/64/128
: This indicates the largest width that the target can support loading or storing atomically (but may not support CAS).cc #32976
r? @alexcrichton