diff --git a/compiler/rustc_data_structures/src/lib.rs b/compiler/rustc_data_structures/src/lib.rs
index 9ded10e9c26..d0f2a4148d3 100644
--- a/compiler/rustc_data_structures/src/lib.rs
+++ b/compiler/rustc_data_structures/src/lib.rs
@@ -101,8 +101,7 @@ macro_rules! unlikely {
 pub mod work_queue;
 pub use atomic_ref::AtomicRef;
 pub mod frozen;
-pub mod mini_map;
-pub mod mini_set;
+pub mod sso;
 pub mod tagged_ptr;
 pub mod temp_dir;
 pub mod unhash;
diff --git a/compiler/rustc_data_structures/src/mini_map.rs b/compiler/rustc_data_structures/src/sso/map.rs
similarity index 79%
rename from compiler/rustc_data_structures/src/mini_map.rs
rename to compiler/rustc_data_structures/src/sso/map.rs
index cd3e949d383..c253e9d6616 100644
--- a/compiler/rustc_data_structures/src/mini_map.rs
+++ b/compiler/rustc_data_structures/src/sso/map.rs
@@ -8,21 +8,21 @@
 ///
 /// Stores elements in a small array up to a certain length
 /// and switches to `HashMap` when that length is exceeded.
-pub enum MiniMap<K, V> {
+pub enum SsoHashMap<K, V> {
     Array(ArrayVec<[(K, V); 8]>),
     Map(FxHashMap<K, V>),
 }
 
-impl<K: Eq + Hash, V> MiniMap<K, V> {
-    /// Creates an empty `MiniMap`.
+impl<K: Eq + Hash, V> SsoHashMap<K, V> {
+    /// Creates an empty `SsoHashMap`.
     pub fn new() -> Self {
-        MiniMap::Array(ArrayVec::new())
+        SsoHashMap::Array(ArrayVec::new())
     }
 
     /// Inserts or updates value in the map.
     pub fn insert(&mut self, key: K, value: V) {
         match self {
-            MiniMap::Array(array) => {
+            SsoHashMap::Array(array) => {
                 for pair in array.iter_mut() {
                     if pair.0 == key {
                         pair.1 = value;
@@ -33,10 +33,10 @@ pub fn insert(&mut self, key: K, value: V) {
                     let mut map: FxHashMap<K, V> = array.drain(..).collect();
                     let (key, value) = error.element();
                     map.insert(key, value);
-                    *self = MiniMap::Map(map);
+                    *self = SsoHashMap::Map(map);
                 }
             }
-            MiniMap::Map(map) => {
+            SsoHashMap::Map(map) => {
                 map.insert(key, value);
             }
         }
@@ -45,7 +45,7 @@ pub fn insert(&mut self, key: K, value: V) {
     /// Return value by key if any.
     pub fn get(&self, key: &K) -> Option<&V> {
         match self {
-            MiniMap::Array(array) => {
+            SsoHashMap::Array(array) => {
                 for pair in array {
                     if pair.0 == *key {
                         return Some(&pair.1);
@@ -53,7 +53,7 @@ pub fn get(&self, key: &K) -> Option<&V> {
                 }
                 return None;
             }
-            MiniMap::Map(map) => {
+            SsoHashMap::Map(map) => {
                 return map.get(key);
             }
         }
diff --git a/compiler/rustc_data_structures/src/sso/mod.rs b/compiler/rustc_data_structures/src/sso/mod.rs
new file mode 100644
index 00000000000..ef634b9adce
--- /dev/null
+++ b/compiler/rustc_data_structures/src/sso/mod.rs
@@ -0,0 +1,5 @@
+mod map;
+mod set;
+
+pub use map::SsoHashMap;
+pub use set::SsoHashSet;
diff --git a/compiler/rustc_data_structures/src/mini_set.rs b/compiler/rustc_data_structures/src/sso/set.rs
similarity index 77%
rename from compiler/rustc_data_structures/src/mini_set.rs
rename to compiler/rustc_data_structures/src/sso/set.rs
index 9d45af723de..b403c9dcc33 100644
--- a/compiler/rustc_data_structures/src/mini_set.rs
+++ b/compiler/rustc_data_structures/src/sso/set.rs
@@ -5,15 +5,15 @@
 ///
 /// Stores elements in a small array up to a certain length
 /// and switches to `HashSet` when that length is exceeded.
-pub enum MiniSet<T> {
+pub enum SsoHashSet<T> {
     Array(ArrayVec<[T; 8]>),
     Set(FxHashSet<T>),
 }
 
-impl<T: Eq + Hash> MiniSet<T> {
-    /// Creates an empty `MiniSet`.
+impl<T: Eq + Hash> SsoHashSet<T> {
+    /// Creates an empty `SsoHashSet`.
     pub fn new() -> Self {
-        MiniSet::Array(ArrayVec::new())
+        SsoHashSet::Array(ArrayVec::new())
     }
 
     /// Adds a value to the set.
@@ -23,19 +23,19 @@ pub fn new() -> Self {
     /// If the set did have this value present, false is returned.
     pub fn insert(&mut self, elem: T) -> bool {
         match self {
-            MiniSet::Array(array) => {
+            SsoHashSet::Array(array) => {
                 if array.iter().any(|e| *e == elem) {
                     false
                 } else {
                     if let Err(error) = array.try_push(elem) {
                         let mut set: FxHashSet<T> = array.drain(..).collect();
                         set.insert(error.element());
-                        *self = MiniSet::Set(set);
+                        *self = SsoHashSet::Set(set);
                     }
                     true
                 }
             }
-            MiniSet::Set(set) => set.insert(elem),
+            SsoHashSet::Set(set) => set.insert(elem),
         }
     }
 }
diff --git a/compiler/rustc_infer/src/infer/combine.rs b/compiler/rustc_infer/src/infer/combine.rs
index a540face4f2..6a1715ef818 100644
--- a/compiler/rustc_infer/src/infer/combine.rs
+++ b/compiler/rustc_infer/src/infer/combine.rs
@@ -35,7 +35,7 @@
 use crate::traits::{Obligation, PredicateObligations};
 
 use rustc_ast as ast;
-use rustc_data_structures::mini_map::MiniMap;
+use rustc_data_structures::sso::SsoHashMap;
 use rustc_hir::def_id::DefId;
 use rustc_middle::traits::ObligationCause;
 use rustc_middle::ty::error::TypeError;
@@ -429,7 +429,7 @@ fn generalize(
             needs_wf: false,
             root_ty: ty,
             param_env: self.param_env,
-            cache: MiniMap::new(),
+            cache: SsoHashMap::new(),
         };
 
         let ty = match generalize.relate(ty, ty) {
@@ -490,7 +490,7 @@ struct Generalizer<'cx, 'tcx> {
 
     param_env: ty::ParamEnv<'tcx>,
 
-    cache: MiniMap<Ty<'tcx>, RelateResult<'tcx, Ty<'tcx>>>,
+    cache: SsoHashMap<Ty<'tcx>, RelateResult<'tcx, Ty<'tcx>>>,
 }
 
 /// Result from a generalization operation. This includes
diff --git a/compiler/rustc_infer/src/infer/outlives/verify.rs b/compiler/rustc_infer/src/infer/outlives/verify.rs
index 21b0836563f..07924298c24 100644
--- a/compiler/rustc_infer/src/infer/outlives/verify.rs
+++ b/compiler/rustc_infer/src/infer/outlives/verify.rs
@@ -1,7 +1,7 @@
 use crate::infer::outlives::env::RegionBoundPairs;
 use crate::infer::{GenericKind, VerifyBound};
 use rustc_data_structures::captures::Captures;
-use rustc_data_structures::mini_set::MiniSet;
+use rustc_data_structures::sso::SsoHashSet;
 use rustc_hir::def_id::DefId;
 use rustc_middle::ty::subst::{GenericArg, GenericArgKind, Subst};
 use rustc_middle::ty::{self, Ty, TyCtxt};
@@ -32,7 +32,7 @@ pub fn new(
     /// Returns a "verify bound" that encodes what we know about
     /// `generic` and the regions it outlives.
     pub fn generic_bound(&self, generic: GenericKind<'tcx>) -> VerifyBound<'tcx> {
-        let mut visited = MiniSet::new();
+        let mut visited = SsoHashSet::new();
         match generic {
             GenericKind::Param(param_ty) => self.param_bound(param_ty),
             GenericKind::Projection(projection_ty) => {
@@ -44,7 +44,7 @@ pub fn generic_bound(&self, generic: GenericKind<'tcx>) -> VerifyBound<'tcx> {
     fn type_bound(
         &self,
         ty: Ty<'tcx>,
-        visited: &mut MiniSet<GenericArg<'tcx>>,
+        visited: &mut SsoHashSet<GenericArg<'tcx>>,
     ) -> VerifyBound<'tcx> {
         match *ty.kind() {
             ty::Param(p) => self.param_bound(p),
@@ -148,7 +148,7 @@ pub fn projection_declared_bounds_from_trait(
     pub fn projection_bound(
         &self,
         projection_ty: ty::ProjectionTy<'tcx>,
-        visited: &mut MiniSet<GenericArg<'tcx>>,
+        visited: &mut SsoHashSet<GenericArg<'tcx>>,
     ) -> VerifyBound<'tcx> {
         debug!("projection_bound(projection_ty={:?})", projection_ty);
 
@@ -186,7 +186,7 @@ pub fn projection_bound(
     fn recursive_bound(
         &self,
         parent: GenericArg<'tcx>,
-        visited: &mut MiniSet<GenericArg<'tcx>>,
+        visited: &mut SsoHashSet<GenericArg<'tcx>>,
     ) -> VerifyBound<'tcx> {
         let mut bounds = parent
             .walk_shallow(visited)
diff --git a/compiler/rustc_middle/src/ty/outlives.rs b/compiler/rustc_middle/src/ty/outlives.rs
index ca992d36e95..4c20141bbe6 100644
--- a/compiler/rustc_middle/src/ty/outlives.rs
+++ b/compiler/rustc_middle/src/ty/outlives.rs
@@ -4,7 +4,7 @@
 
 use crate::ty::subst::{GenericArg, GenericArgKind};
 use crate::ty::{self, Ty, TyCtxt, TypeFoldable};
-use rustc_data_structures::mini_set::MiniSet;
+use rustc_data_structures::sso::SsoHashSet;
 use smallvec::SmallVec;
 
 #[derive(Debug)]
@@ -51,7 +51,7 @@ impl<'tcx> TyCtxt<'tcx> {
     /// Push onto `out` all the things that must outlive `'a` for the condition
     /// `ty0: 'a` to hold. Note that `ty0` must be a **fully resolved type**.
     pub fn push_outlives_components(self, ty0: Ty<'tcx>, out: &mut SmallVec<[Component<'tcx>; 4]>) {
-        let mut visited = MiniSet::new();
+        let mut visited = SsoHashSet::new();
         compute_components(self, ty0, out, &mut visited);
         debug!("components({:?}) = {:?}", ty0, out);
     }
@@ -61,7 +61,7 @@ fn compute_components(
     tcx: TyCtxt<'tcx>,
     ty: Ty<'tcx>,
     out: &mut SmallVec<[Component<'tcx>; 4]>,
-    visited: &mut MiniSet<GenericArg<'tcx>>,
+    visited: &mut SsoHashSet<GenericArg<'tcx>>,
 ) {
     // Descend through the types, looking for the various "base"
     // components and collecting them into `out`. This is not written
@@ -142,7 +142,7 @@ fn compute_components(
                     // OutlivesProjectionComponents.  Continue walking
                     // through and constrain Pi.
                     let mut subcomponents = smallvec![];
-                    let mut subvisited = MiniSet::new();
+                    let mut subvisited = SsoHashSet::new();
                     compute_components_recursive(tcx, ty.into(), &mut subcomponents, &mut subvisited);
                     out.push(Component::EscapingProjection(subcomponents.into_iter().collect()));
                 }
@@ -194,7 +194,7 @@ fn compute_components_recursive(
     tcx: TyCtxt<'tcx>,
     parent: GenericArg<'tcx>,
     out: &mut SmallVec<[Component<'tcx>; 4]>,
-    visited: &mut MiniSet<GenericArg<'tcx>>,
+    visited: &mut SsoHashSet<GenericArg<'tcx>>,
 ) {
     for child in parent.walk_shallow(visited) {
         match child.unpack() {
diff --git a/compiler/rustc_middle/src/ty/print/mod.rs b/compiler/rustc_middle/src/ty/print/mod.rs
index 225ea2399fb..2e00be2395b 100644
--- a/compiler/rustc_middle/src/ty/print/mod.rs
+++ b/compiler/rustc_middle/src/ty/print/mod.rs
@@ -2,7 +2,7 @@
 use crate::ty::{self, DefIdTree, Ty, TyCtxt};
 
 use rustc_data_structures::fx::FxHashSet;
-use rustc_data_structures::mini_set::MiniSet;
+use rustc_data_structures::sso::SsoHashSet;
 use rustc_hir::def_id::{CrateNum, DefId};
 use rustc_hir::definitions::{DefPathData, DisambiguatedDefPathData};
 
@@ -269,7 +269,7 @@ fn default_print_impl_path(
 /// deeply nested tuples that have no DefId.
 fn characteristic_def_id_of_type_cached<'a>(
     ty: Ty<'a>,
-    visited: &mut MiniSet<Ty<'a>>,
+    visited: &mut SsoHashSet<Ty<'a>>,
 ) -> Option<DefId> {
     match *ty.kind() {
         ty::Adt(adt_def, _) => Some(adt_def.did),
@@ -316,7 +316,7 @@ fn characteristic_def_id_of_type_cached<'a>(
     }
 }
 pub fn characteristic_def_id_of_type(ty: Ty<'_>) -> Option<DefId> {
-    characteristic_def_id_of_type_cached(ty, &mut MiniSet::new())
+    characteristic_def_id_of_type_cached(ty, &mut SsoHashSet::new())
 }
 
 impl<'tcx, P: Printer<'tcx>> Print<'tcx, P> for ty::RegionKind {
diff --git a/compiler/rustc_middle/src/ty/walk.rs b/compiler/rustc_middle/src/ty/walk.rs
index 80ade7dda4c..357a0dd65c4 100644
--- a/compiler/rustc_middle/src/ty/walk.rs
+++ b/compiler/rustc_middle/src/ty/walk.rs
@@ -3,7 +3,7 @@
 
 use crate::ty;
 use crate::ty::subst::{GenericArg, GenericArgKind};
-use rustc_data_structures::mini_set::MiniSet;
+use rustc_data_structures::sso::SsoHashSet;
 use smallvec::{self, SmallVec};
 
 // The TypeWalker's stack is hot enough that it's worth going to some effort to
@@ -13,7 +13,7 @@
 pub struct TypeWalker<'tcx> {
     stack: TypeWalkerStack<'tcx>,
     last_subtree: usize,
-    visited: MiniSet<GenericArg<'tcx>>,
+    visited: SsoHashSet<GenericArg<'tcx>>,
 }
 
 /// An iterator for walking the type tree.
@@ -26,7 +26,7 @@ pub struct TypeWalker<'tcx> {
 /// skips any types that are already there.
 impl<'tcx> TypeWalker<'tcx> {
     pub fn new(root: GenericArg<'tcx>) -> Self {
-        Self { stack: smallvec![root], last_subtree: 1, visited: MiniSet::new() }
+        Self { stack: smallvec![root], last_subtree: 1, visited: SsoHashSet::new() }
     }
 
     /// Skips the subtree corresponding to the last type
@@ -87,7 +87,7 @@ pub fn walk(self) -> TypeWalker<'tcx> {
     /// and skips any types that are already there.
     pub fn walk_shallow(
         self,
-        visited: &mut MiniSet<GenericArg<'tcx>>,
+        visited: &mut SsoHashSet<GenericArg<'tcx>>,
     ) -> impl Iterator<Item = GenericArg<'tcx>> {
         let mut stack = SmallVec::new();
         push_inner(&mut stack, self);
diff --git a/compiler/rustc_trait_selection/src/traits/query/normalize.rs b/compiler/rustc_trait_selection/src/traits/query/normalize.rs
index 3dcebbcc244..bdbf45f78a2 100644
--- a/compiler/rustc_trait_selection/src/traits/query/normalize.rs
+++ b/compiler/rustc_trait_selection/src/traits/query/normalize.rs
@@ -7,7 +7,7 @@
 use crate::infer::{InferCtxt, InferOk};
 use crate::traits::error_reporting::InferCtxtExt;
 use crate::traits::{Obligation, ObligationCause, PredicateObligation, Reveal};
-use rustc_data_structures::mini_map::MiniMap;
+use rustc_data_structures::sso::SsoHashMap;
 use rustc_data_structures::stack::ensure_sufficient_stack;
 use rustc_infer::traits::Normalized;
 use rustc_middle::ty::fold::{TypeFoldable, TypeFolder};
@@ -58,7 +58,7 @@ fn normalize<T>(&self, value: &T) -> Result<Normalized<'tcx, T>, NoSolution>
             param_env: self.param_env,
             obligations: vec![],
             error: false,
-            cache: MiniMap::new(),
+            cache: SsoHashMap::new(),
             anon_depth: 0,
         };
 
@@ -87,7 +87,7 @@ struct QueryNormalizer<'cx, 'tcx> {
     cause: &'cx ObligationCause<'tcx>,
     param_env: ty::ParamEnv<'tcx>,
     obligations: Vec<PredicateObligation<'tcx>>,
-    cache: MiniMap<Ty<'tcx>, Ty<'tcx>>,
+    cache: SsoHashMap<Ty<'tcx>, Ty<'tcx>>,
     error: bool,
     anon_depth: usize,
 }