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45740acd34
Simplify memory ordering intrinsics This changes the names of the atomic intrinsics to always fully include their memory ordering arguments. ```diff - atomic_cxchg + atomic_cxchg_seqcst_seqcst - atomic_cxchg_acqrel + atomic_cxchg_acqrel_release - atomic_cxchg_acqrel_failrelaxed + atomic_cxchg_acqrel_relaxed // And so on. ``` - `seqcst` is no longer implied - The failure ordering on chxchg is no longer implied in some cases, but now always explicitly part of the name. - `release` is no longer shortened to just `rel`. That was especially confusing, since `relaxed` also starts with `rel`. - `acquire` is no longer shortened to just `acq`, such that the names now all match the `std::sync::atomic::Ordering` variants exactly. - This now allows for more combinations on the compare exchange operations, such as `atomic_cxchg_acquire_release`, which is necessary for #68464. - This PR only exposes the new possibilities through unstable intrinsics, but not yet through the stable API. That's for [a separate PR](https://github.com/rust-lang/rust/pull/98383) that requires an FCP. Suffixes for operations with a single memory order: | Order | Before | After | |---------|--------------|------------| | Relaxed | `_relaxed` | `_relaxed` | | Acquire | `_acq` | `_acquire` | | Release | `_rel` | `_release` | | AcqRel | `_acqrel` | `_acqrel` | | SeqCst | (none) | `_seqcst` | Suffixes for compare-and-exchange operations with two memory orderings: | Success | Failure | Before | After | |---------|---------|--------------------------|--------------------| | Relaxed | Relaxed | `_relaxed` | `_relaxed_relaxed` | | Relaxed | Acquire | ❌ | `_relaxed_acquire` | | Relaxed | SeqCst | ❌ | `_relaxed_seqcst` | | Acquire | Relaxed | `_acq_failrelaxed` | `_acquire_relaxed` | | Acquire | Acquire | `_acq` | `_acquire_acquire` | | Acquire | SeqCst | ❌ | `_acquire_seqcst` | | Release | Relaxed | `_rel` | `_release_relaxed` | | Release | Acquire | ❌ | `_release_acquire` | | Release | SeqCst | ❌ | `_release_seqcst` | | AcqRel | Relaxed | `_acqrel_failrelaxed` | `_acqrel_relaxed` | | AcqRel | Acquire | `_acqrel` | `_acqrel_acquire` | | AcqRel | SeqCst | ❌ | `_acqrel_seqcst` | | SeqCst | Relaxed | `_failrelaxed` | `_seqcst_relaxed` | | SeqCst | Acquire | `_failacq` | `_seqcst_acquire` | | SeqCst | SeqCst | (none) | `_seqcst_seqcst` | |
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| Cargo.toml | ||
| README.md | ||
Please read the rustc-dev-guide chapter on Backend Agnostic Codegen.