[TEST] Test a hashbrown branch with backward shift deletion

Cargo.lock

@@ -1627,7 +1627,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1033caf0b349c518623b5396bfb2cf0bddf44f0306d543a250e5743297aafd10"
 dependencies = [
  "fnv",
- "hashbrown",
+ "hashbrown 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "indexmap",
  "stable_deref_trait",
 ]
@@ -1688,6 +1688,14 @@ dependencies = [
  "serde_core",
 ]
 
+[[package]]
+name = "hashbrown"
+version = "0.17.1"
+source = "git+https://github.com/Zoxc/hashbrown.git?branch=linear-probes#dc5066465f34332634fadf2abb0da9d095da2348"
+dependencies = [
+ "foldhash 0.2.0",
+]
+
 [[package]]
 name = "heck"
 version = "0.5.0"
@@ -1977,7 +1985,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d466e9454f08e4a911e14806c24e16fba1b4c121d1ea474396f396069cf949d9"
 dependencies = [
  "equivalent",
- "hashbrown",
+ "hashbrown 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde",
  "serde_core",
 ]
@@ -2783,7 +2791,7 @@ checksum = "2e5a6c098c7a3b6547378093f5cc30bc54fd361ce711e05293a5cc589562739b"
 dependencies = [
  "crc32fast",
  "flate2",
- "hashbrown",
+ "hashbrown 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "indexmap",
  "memchr",
  "ruzstd",
@@ -3456,7 +3464,7 @@ checksum = "d9776093b7ca170454ab1406954f7b7d97a57c51dc6c0642957fb2ef25c2d399"
 dependencies = [
  "bytecheck",
  "bytes",
- "hashbrown",
+ "hashbrown 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "indexmap",
  "munge",
  "ptr_meta",
@@ -3915,7 +3923,7 @@ dependencies = [
  "either",
  "elsa",
  "ena",
- "hashbrown",
+ "hashbrown 0.17.1 (git+https://github.com/Zoxc/hashbrown.git?branch=linear-probes)",
  "indexmap",
  "jobserver",
  "libc",
@@ -4760,6 +4768,7 @@ dependencies = [
 name = "rustc_serialize"
 version = "0.0.0"
 dependencies = [
+ "hashbrown 0.17.1 (git+https://github.com/Zoxc/hashbrown.git?branch=linear-probes)",
  "indexmap",
  "rustc_hashes",
  "rustc_macros",
@@ -4983,6 +4992,7 @@ dependencies = [
  "bitflags",
  "derive-where",
  "ena",
+ "hashbrown 0.17.1 (git+https://github.com/Zoxc/hashbrown.git?branch=linear-probes)",
  "indexmap",
  "rustc-hash 2.1.1",
  "rustc_abi",
@@ -5718,7 +5728,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b5938a79ecf9cb8198d525ddb37cd8841f66ab98073f6a123af7ed7cdcbb73ae"
 dependencies = [
  "gimli 0.34.0",
- "hashbrown",
+ "hashbrown 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "itertools",
  "object 0.39.1",
  "tracing",
@@ -6464,7 +6474,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d92fc335fb6d48f46bda1d8b26b69e28320c15ac3272208333833d6e217e2b4a"
 dependencies = [
  "bitflags",
- "hashbrown",
+ "hashbrown 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "indexmap",
  "semver",
  "serde",
@@ -6883,7 +6893,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6f815340f0bb65d9775ae21e56b503b496683557b9b627b195d2766c25fb24ae"
 dependencies = [
  "anyhow",
- "hashbrown",
+ "hashbrown 0.17.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "id-arena",
  "indexmap",
  "log",

compiler/rustc_ast_lowering/src/asm.rs

@@ -1,7 +1,6 @@
-use std::collections::hash_map::Entry;
-
 use rustc_ast::*;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet, FxIndexMap};
+use rustc_data_structures::hash_map::Entry;
 use rustc_errors::msg;
 use rustc_hir as hir;
 use rustc_hir::def::{DefKind, Res};
@@ -452,7 +451,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                     overlapping_with.push(reg);
                 });
                 let output_used =
-                    overlapping_with.iter().any(|reg| used_output_regs.contains_key(&reg));
+                    overlapping_with.iter().any(|reg| used_output_regs.contains_key(reg));
 
                 if !output_used {
                     operands.push((

compiler/rustc_borrowck/src/borrow_set.rs

@@ -1,8 +1,8 @@
-use std::collections::hash_map::Entry;
 use std::fmt;
 use std::ops::Index;
 
 use rustc_data_structures::fx::{FxHashMap, FxIndexMap, FxIndexSet};
+use rustc_data_structures::hash_map::Entry;
 use rustc_hir::Mutability;
 use rustc_index::IndexVec;
 use rustc_index::bit_set::DenseBitSet;
@@ -102,7 +102,7 @@ impl<'tcx> BorrowSet<'tcx> {
 
     // Public method to support Creusot.
     pub fn activations_at_location(&self, location: &Location) -> &[BorrowIndex] {
-        self.activation_map.get(&location).map_or(&[], |activations| &activations[..])
+        self.activation_map.get(location).map_or(&[], |activations| &activations[..])
     }
 
     // Public method to support Creusot.

compiler/rustc_codegen_cranelift/src/pretty_clif.rs

@@ -124,7 +124,7 @@ impl CommentWriter {
     ) {
         debug_assert!(self.enabled);
 
-        use std::collections::hash_map::Entry;
+        use rustc_data_structures::hash_map::Entry;
         match self.entity_comments.entry(entity.into()) {
             Entry::Occupied(mut occ) => {
                 occ.get_mut().push('\n');
@@ -143,7 +143,7 @@ impl CommentWriter {
     ) {
         debug_assert!(self.enabled);
 
-        use std::collections::hash_map::Entry;
+        use rustc_data_structures::hash_map::Entry;
         match self.inst_post_comments.entry(entity) {
             Entry::Occupied(mut occ) => {
                 occ.get_mut().push('\n');
@@ -210,7 +210,7 @@ impl FuncWriter for &'_ CommentWriter {
         inst: Inst,
         indent: usize,
     ) -> fmt::Result {
-        if let Some(comment) = self.entity_comments.get(&inst.into()) {
+        if let Some(comment) = self.entity_comments.get::<AnyEntity>(&inst.into()) {
             writeln!(w, "; {}", comment.replace('\n', "\n; "))?;
         }
         PlainWriter.write_instruction(w, func, aliases, inst, indent)?;

compiler/rustc_codegen_ssa/src/back/symbol_export.rs

@@ -1,9 +1,8 @@
-use std::collections::hash_map::Entry::*;
-
 use rustc_abi::{CanonAbi, X86Call};
 use rustc_ast::expand::allocator::{AllocatorKind, NO_ALLOC_SHIM_IS_UNSTABLE, global_fn_name};
 use rustc_crate_store::CrateDepKind;
 use rustc_data_structures::fx::FxHashSet;
+use rustc_data_structures::hash_map::Entry::*;
 use rustc_data_structures::unord::UnordMap;
 use rustc_hir as hir;
 use rustc_hir::def::DefKind;

compiler/rustc_codegen_ssa/src/mir/debuginfo.rs

@@ -1,9 +1,9 @@
-use std::collections::hash_map::Entry;
 use std::marker::PhantomData;
 use std::ops::Range;
 
 use rustc_abi::{BackendRepr, FieldIdx, FieldsShape, Size, VariantIdx};
 use rustc_data_structures::fx::FxHashMap;
+use rustc_data_structures::hash_map::Entry;
 use rustc_index::IndexVec;
 use rustc_index::bit_set::DenseBitSet;
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags;

compiler/rustc_codegen_ssa/src/target_features.rs

@@ -538,7 +538,7 @@ pub(crate) fn provide(providers: &mut Providers) {
                 // hope that this doesn't cause issues anywhere else in the compiler...
                 let mut result: UnordMap<String, Stability> = Default::default();
                 for (name, stability) in rustc_target::target_features::all_rust_features() {
-                    use std::collections::hash_map::Entry;
+                    use rustc_data_structures::hash_map::Entry;
                     match result.entry(name.to_owned()) {
                         Entry::Vacant(vacant_entry) => {
                             vacant_entry.insert(stability);

compiler/rustc_const_eval/src/interpret/eval_context.rs

@@ -1,9 +1,9 @@
 use std::cell::RefCell;
-use std::collections::hash_map::Entry;
 
 use either::{Left, Right};
 use rustc_abi::{Align, HasDataLayout, Size, TargetDataLayout};
 use rustc_data_structures::fx::FxHashMap;
+use rustc_data_structures::hash_map::Entry;
 use rustc_hir::def_id::DefId;
 use rustc_middle::mir::interpret::{ErrorHandled, InvalidMetaKind, ReportedErrorInfo};
 use rustc_middle::query::TyCtxtAt;

compiler/rustc_data_structures/Cargo.toml

@@ -34,7 +34,8 @@ tracing = "0.1"
 # tidy-alphabetical-end
 
 [dependencies.hashbrown]
-version = "0.17.0"
+git = "https://github.com/Zoxc/hashbrown.git"
+branch = "linear-probes"
 default-features = false
 features = ["nightly"]   # for may_dangle
 

compiler/rustc_data_structures/src/fx.rs

@@ -1,6 +1,14 @@
-pub use rustc_hash::{FxBuildHasher, FxHashMap, FxHashSet, FxHasher};
+pub use rustc_hash::{FxBuildHasher, FxHasher};
 
-pub type StdEntry<'a, K, V> = std::collections::hash_map::Entry<'a, K, V>;
+// These are `hashbrown`'s hash map and set rather than the standard library's, even though the
+// standard library's are themselves a thin wrapper around `hashbrown`. Depending on `hashbrown`
+// directly means the compiler uses the version this workspace resolves, rather than whichever copy
+// happens to be baked into the standard library it is compiled against. [LLM-generated]
+pub type FxHashMap<K, V> = hashbrown::HashMap<K, V, FxBuildHasher>;
+pub type FxHashSet<V> = hashbrown::HashSet<V, FxBuildHasher>;
+
+pub type MapEntry<'a, K, V> = hashbrown::hash_map::Entry<'a, K, V, FxBuildHasher>;
+pub type MapOccupiedError<'a, K, V> = hashbrown::hash_map::OccupiedError<'a, K, V, FxBuildHasher>;
 
 pub type FxIndexMap<K, V> = indexmap::IndexMap<K, V, FxBuildHasher>;
 pub type FxIndexSet<V> = indexmap::IndexSet<V, FxBuildHasher>;
@@ -14,7 +22,7 @@ macro_rules! define_id_collections {
     ($map_name:ident, $set_name:ident, $entry_name:ident, $key:ty) => {
         pub type $map_name<T> = $crate::unord::UnordMap<$key, T>;
         pub type $set_name = $crate::unord::UnordSet<$key>;
-        pub type $entry_name<'a, T> = $crate::fx::StdEntry<'a, $key, T>;
+        pub type $entry_name<'a, T> = $crate::fx::MapEntry<'a, $key, T>;
     };
 }
 

compiler/rustc_data_structures/src/lib.rs

@@ -22,7 +22,6 @@
 #![feature(dropck_eyepatch)]
 #![feature(extend_one)]
 #![feature(file_buffered)]
-#![feature(map_try_insert)]
 #![feature(min_specialization)]
 #![feature(negative_impls)]
 #![feature(nonzero_internals)]
@@ -44,10 +43,10 @@ use std::fmt;
 
 pub use atomic_ref::AtomicRef;
 pub use ena::{snapshot_vec, undo_log, unify};
-// Re-export `hashbrown::hash_table`, because it's part of our API
-// (via `ShardedHashMap`), and because it lets other compiler crates use the
-// lower-level `HashTable` API without a tricky `hashbrown` dependency.
-pub use hashbrown::hash_table;
+// Re-export `hashbrown`'s map, set and table modules, because they are part of our API
+// (via `FxHashMap`, `FxHashSet` and `ShardedHashMap`), and because it lets other compiler crates
+// use the lower-level `HashTable` API without a tricky `hashbrown` dependency.
+pub use hashbrown::{hash_map, hash_set, hash_table};
 pub use rustc_index::static_assert_size;
 // Re-export some data-structure crates which are part of our public API.
 pub use {either, indexmap, smallvec, thin_vec};

compiler/rustc_data_structures/src/marker.rs

@@ -92,6 +92,8 @@ impl_dyn_send!(
     [crate::tagged_ptr::TaggedRef<'a, P, T> where 'a, P: Sync, T: Send + crate::tagged_ptr::Tag]
     [rustc_arena::TypedArena<T> where T: DynSend]
     [hashbrown::HashTable<T> where T: DynSend]
+    [hashbrown::HashSet<K, S> where K: DynSend, S: DynSend]
+    [hashbrown::HashMap<K, V, S> where K: DynSend, V: DynSend, S: DynSend]
     [indexmap::IndexSet<V, S> where V: DynSend, S: DynSend]
     [indexmap::IndexMap<K, V, S> where K: DynSend, V: DynSend, S: DynSend]
     [thin_vec::ThinVec<T> where T: DynSend]
@@ -178,6 +180,8 @@ impl_dyn_sync!(
     [parking_lot::lock_api::Mutex<R, T> where R: DynSync, T: ?Sized + DynSend]
     [parking_lot::lock_api::RwLock<R, T> where R: DynSync, T: ?Sized + DynSend + DynSync]
     [hashbrown::HashTable<T> where T: DynSync]
+    [hashbrown::HashSet<K, S> where K: DynSync, S: DynSync]
+    [hashbrown::HashMap<K, V, S> where K: DynSync, V: DynSync, S: DynSync]
     [indexmap::IndexSet<V, S> where V: DynSync, S: DynSync]
     [indexmap::IndexMap<K, V, S> where K: DynSync, V: DynSync, S: DynSync]
     [smallvec::SmallVec<A> where A: smallvec::Array + DynSync]

compiler/rustc_data_structures/src/obligation_forest/mod.rs

@@ -70,11 +70,11 @@
 //! aren't needed anymore.
 
 use std::cell::Cell;
-use std::collections::hash_map::Entry;
 use std::fmt::Debug;
 use std::hash;
 use std::marker::PhantomData;
 
+use hashbrown::hash_map::Entry;
 use thin_vec::ThinVec;
 use tracing::debug;
 

compiler/rustc_data_structures/src/profiling.rs

@@ -82,7 +82,6 @@
 //! [mm]: https://github.com/rust-lang/measureme/
 
 use std::borrow::Borrow;
-use std::collections::hash_map::Entry;
 use std::error::Error;
 use std::fmt::Display;
 use std::path::Path;
@@ -91,6 +90,7 @@ use std::sync::atomic::Ordering;
 use std::time::{Duration, Instant};
 use std::{fs, hint, process};
 
+use hashbrown::hash_map::Entry;
 pub use measureme::EventId;
 use measureme::{EventIdBuilder, Profiler, SerializableString, StringId};
 use parking_lot::RwLock;

compiler/rustc_data_structures/src/sync.rs

@@ -22,7 +22,6 @@
 //! |                         |                          | `parking_lot::Mutex<T>`         |
 //! | `RwLock<T>`             | `parking_lot::RwLock<T>` | `parking_lot::RwLock<T>`        |
 
-use std::collections::HashMap;
 use std::hash::{BuildHasher, Hash};
 
 pub use parking_lot::{
@@ -163,7 +162,7 @@ pub trait HashMapExt<K, V> {
     fn insert_same(&mut self, key: K, value: V);
 }
 
-impl<K: Eq + Hash, V: Eq, S: BuildHasher> HashMapExt<K, V> for HashMap<K, V, S> {
+impl<K: Eq + Hash, V: Eq, S: BuildHasher> HashMapExt<K, V> for hashbrown::HashMap<K, V, S> {
     fn insert_same(&mut self, key: K, value: V) {
         self.entry(key).and_modify(|old| assert!(*old == value)).or_insert(value);
     }

compiler/rustc_data_structures/src/unord.rs

@@ -3,15 +3,14 @@
 //! as required by the query system.
 
 use std::borrow::{Borrow, BorrowMut};
-use std::collections::hash_map::{Entry, OccupiedError};
 use std::hash::Hash;
 use std::iter::{Product, Sum};
 use std::ops::Index;
 
 use rustc_macros::{Decodable_NoContext, Encodable_NoContext};
 
 use crate::fingerprint::Fingerprint;
-use crate::fx::{FxBuildHasher, FxHashMap, FxHashSet};
+use crate::fx::{FxBuildHasher, FxHashMap, FxHashSet, MapEntry, MapOccupiedError};
 use crate::stable_hash::{
     StableCompare, StableHash, StableHashCtxt, StableHasher, ToStableHashKey,
 };
@@ -501,7 +500,7 @@ impl<K: Eq + Hash, V> UnordMap<K, V> {
     }
 
     #[inline]
-    pub fn try_insert(&mut self, k: K, v: V) -> Result<&mut V, OccupiedError<'_, K, V>> {
+    pub fn try_insert(&mut self, k: K, v: V) -> Result<&mut V, MapOccupiedError<'_, K, V>> {
         self.inner.try_insert(k, v)
     }
 
@@ -520,7 +519,7 @@ impl<K: Eq + Hash, V> UnordMap<K, V> {
     }
 
     #[inline]
-    pub fn entry(&mut self, key: K) -> Entry<'_, K, V> {
+    pub fn entry(&mut self, key: K) -> MapEntry<'_, K, V> {
         self.inner.entry(key)
     }
 

compiler/rustc_expand/src/mbe/diagnostics.rs

@@ -293,7 +293,7 @@ impl<'dcx, 'matcher> Tracker<'matcher> for CollectTrackerAndEmitter<'dcx, 'match
             bug!("`Self::prepare()` was not called to initialize context");
         };
 
-        #[expect(
+        #[allow(
             rustc::potential_query_instability,
             reason = "sorting the results deterministically afterwards"
         )]

compiler/rustc_expand/src/mbe/macro_rules.rs

@@ -1,5 +1,4 @@
 use std::borrow::Cow;
-use std::collections::hash_map::Entry;
 use std::sync::Arc;
 use std::{mem, slice};
 
@@ -13,6 +12,7 @@ use rustc_ast_pretty::pprust;
 use rustc_attr_ir::diagnostic::Directive;
 use rustc_attr_ir::{self as attrs, find_attr};
 use rustc_data_structures::fx::{FxHashMap, FxIndexMap};
+use rustc_data_structures::hash_map::Entry;
 use rustc_errors::{Applicability, Diag, ErrorGuaranteed, MultiSpan};
 use rustc_feature::Features;
 use rustc_hir::def::MacroKinds;

compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs

@@ -1,8 +1,8 @@
-use std::collections::hash_map::Entry;
 use std::slice;
 
 use rustc_abi::FieldIdx;
 use rustc_data_structures::fx::FxHashSet;
+use rustc_data_structures::hash_map::Entry;
 use rustc_data_structures::thin_vec::ThinVec;
 use rustc_errors::{
     Applicability, Diag, DiagCtxtHandle, Diagnostic, ErrorGuaranteed, Level, MultiSpan,