Using FxHash* instead of Hash* (microsoft#816)

Using `rustc`'s `FxHashSet` and `FxHashMap` and disabling the use of
`std::collections::Hash(Set|Map)`

```console
Teleport evaluation     time:   [80.908 µs 81.012 µs 81.138 µs]
                        change: [-9.0801% -8.7843% -8.4988%] (p = 0.00 < 0.05)
                        Performance has improved.

Deutsch-Jozsa evaluation
                        time:   [21.520 ms 21.534 ms 21.548 ms]
                        change: [-2.6201% -2.4535% -2.3096%] (p = 0.00 < 0.05)
                        Performance has improved.

Large file parity evaluation
                        time:   [33.821 ms 33.876 ms 33.942 ms]
                        change: [-0.8022% -0.4683% -0.1777%] (p = 0.00 < 0.05)
                        Change within noise threshold.

Large input file        time:   [16.596 ms 16.614 ms 16.632 ms]
                        change: [-6.6542% -6.4932% -6.3307%] (p = 0.00 < 0.05)
                        Performance has improved.

Standard library        time:   [7.3145 ms 7.3215 ms 7.3294 ms]
                        change: [-4.6977% -4.5701% -4.4439%] (p = 0.00 < 0.05)
                        Performance has improved.
```

Author: idavis

Cargo.lock

@@ -46,6 +46,7 @@ num-complex = "0.4"
 num-traits = "0.2"
 indenter = "0.3"
 regex-lite = "0.1"
+rustc-hash = "1.1.0"
 serde = "1.0"
 serde-wasm-bindgen = "0.6"
 wasm-bindgen = "0.2"

Cargo.toml

@@ -0,0 +1,4 @@
+disallowed-types = [
+    { path = "std::collections::HashMap", reason = "use FxHashMap instead" },
+    { path = "std::collections::HashSet", reason = "use FxHashSet instead" },
+]

clippy.toml

@@ -25,6 +25,7 @@ qsc_fir = { path = "../qsc_fir" }
 qsc_hir = { path = "../qsc_hir" }
 qsc_passes = { path = "../qsc_passes" }
 qsc_project = { path = "../qsc_project", features = ["fs"] }
+rustc-hash = { workspace = true }
 thiserror = { workspace = true }
 
 [dev-dependencies]

compiler/qsc/Cargo.toml

@@ -34,7 +34,7 @@ use qsc_frontend::{
     error::WithSource,
 };
 use qsc_passes::PackageType;
-use std::collections::HashSet;
+use rustc_hash::FxHashSet;
 use thiserror::Error;
 
 impl Error {
@@ -561,7 +561,7 @@ pub struct BreakpointSpan {
 }
 
 struct BreakpointCollector<'a> {
-    statements: HashSet<BreakpointSpan>,
+    statements: FxHashSet<BreakpointSpan>,
     sources: &'a SourceMap,
     offset: u32,
     package: &'a Package,
@@ -570,7 +570,7 @@ struct BreakpointCollector<'a> {
 impl<'a> BreakpointCollector<'a> {
     fn new(sources: &'a SourceMap, offset: u32, package: &'a Package) -> Self {
         Self {
-            statements: HashSet::new(),
+            statements: FxHashSet::default(),
             sources,
             offset,
             package,

compiler/qsc/src/interpret/stateful.rs

@@ -17,6 +17,7 @@ qsc_data_structures = { path = "../qsc_data_structures" }
 qsc_fir = { path = "../qsc_fir" }
 qsc_hir = { path = "../qsc_hir" }
 rand =  { workspace = true }
+rustc-hash = { workspace = true }
 thiserror = { workspace = true }
 
 [dev-dependencies]

compiler/qsc_eval/Cargo.toml

@@ -28,8 +28,9 @@ use qsc_fir::fir::{
     PackageId, PatKind, PrimField, Res, SpecBody, SpecGen, StmtKind, StringComponent, UnOp,
 };
 use qsc_fir::fir::{BlockId, ExprId, PatId, StmtId};
+use rustc_hash::FxHashMap;
 use std::{
-    collections::{hash_map::Entry, HashMap},
+    collections::hash_map::Entry,
     fmt::{self, Display, Formatter, Write},
     iter,
     ops::Neg,
@@ -386,7 +387,7 @@ impl Env {
 
 #[derive(Default)]
 struct Scope {
-    bindings: HashMap<NodeId, Variable>,
+    bindings: FxHashMap<NodeId, Variable>,
     frame_id: usize,
 }
 

compiler/qsc_eval/src/lib.rs

@@ -12,3 +12,4 @@ license.workspace = true
 indenter = { workspace = true }
 num-bigint = { workspace = true }
 qsc_data_structures = { path = "../qsc_data_structures" }
+rustc-hash = { workspace = true }

compiler/qsc_fir/Cargo.toml

@@ -6,7 +6,8 @@ use crate::{
     ty::Scheme,
 };
 use qsc_data_structures::index_map;
-use std::{collections::HashMap, rc::Rc};
+use rustc_hash::FxHashMap;
+use std::rc::Rc;
 
 pub struct Global {
     pub namespace: Rc<str>,
@@ -32,8 +33,8 @@ pub struct Term {
 
 #[derive(Default)]
 pub struct Table {
-    tys: HashMap<Rc<str>, HashMap<Rc<str>, Ty>>,
-    terms: HashMap<Rc<str>, HashMap<Rc<str>, Term>>,
+    tys: FxHashMap<Rc<str>, FxHashMap<Rc<str>, Ty>>,
+    terms: FxHashMap<Rc<str>, FxHashMap<Rc<str>, Term>>,
 }
 
 impl Table {
@@ -50,8 +51,8 @@ impl Table {
 
 impl FromIterator<Global> for Table {
     fn from_iter<T: IntoIterator<Item = Global>>(iter: T) -> Self {
-        let mut tys: HashMap<_, HashMap<_, _>> = HashMap::new();
-        let mut terms: HashMap<_, HashMap<_, _>> = HashMap::new();
+        let mut tys: FxHashMap<_, FxHashMap<_, _>> = FxHashMap::default();
+        let mut terms: FxHashMap<_, FxHashMap<_, _>> = FxHashMap::default();
         for global in iter {
             match global.kind {
                 Kind::Ty(ty) => {

compiler/qsc_fir/src/global.rs

@@ -3,10 +3,10 @@
 
 use indenter::{indented, Indented};
 use qsc_data_structures::span::Span;
+use rustc_hash::FxHashMap;
 
 use crate::fir::{CallableKind, FieldPath, Functor, ItemId, Res};
 use std::{
-    collections::HashMap,
     fmt::{self, Debug, Display, Formatter, Write},
     rc::Rc,
 };
@@ -109,7 +109,7 @@ impl Scheme {
     /// Returns an error if the given arguments do not match the scheme parameters.
     pub fn instantiate(&self, args: &[GenericArg]) -> Result<Arrow, InstantiationError> {
         if args.len() == self.params.len() {
-            let args: HashMap<_, _> = self
+            let args: FxHashMap<_, _> = self
                 .params
                 .iter()
                 .enumerate()

compiler/qsc_fir/src/ty.rs

@@ -17,6 +17,7 @@ qsc_ast = { path = "../qsc_ast" }
 qsc_data_structures = { path = "../qsc_data_structures" }
 qsc_hir = { path = "../qsc_hir" }
 qsc_parse = { path = "../qsc_parse" }
+rustc-hash = { workspace = true }
 thiserror = { workspace = true }
 
 [dev-dependencies]

compiler/qsc_frontend/Cargo.toml

@@ -12,10 +12,8 @@ use qsc_hir::{
     ty::{Arrow, FunctorSetValue, Ty},
     visit::{self, Visitor},
 };
-use std::{
-    collections::{HashMap, HashSet},
-    iter,
-};
+use rustc_hash::{FxHashMap, FxHashSet};
+use std::iter;
 
 pub(super) struct Lambda {
     pub(super) kind: CallableKind,
@@ -30,8 +28,8 @@ pub(super) struct PartialApp {
 }
 
 struct VarFinder {
-    bindings: HashSet<NodeId>,
-    uses: HashSet<NodeId>,
+    bindings: FxHashSet<NodeId>,
+    uses: FxHashSet<NodeId>,
 }
 
 impl VarFinder {
@@ -63,7 +61,7 @@ impl Visitor<'_> for VarFinder {
 }
 
 struct VarReplacer<'a> {
-    substitutions: &'a HashMap<NodeId, NodeId>,
+    substitutions: &'a FxHashMap<NodeId, NodeId>,
 }
 
 impl VarReplacer<'_> {
@@ -91,14 +89,14 @@ pub(super) fn lift(
     span: Span,
 ) -> (Vec<NodeId>, CallableDecl) {
     let mut finder = VarFinder {
-        bindings: HashSet::new(),
-        uses: HashSet::new(),
+        bindings: FxHashSet::default(),
+        uses: FxHashSet::default(),
     };
     finder.visit_pat(&lambda.input);
     finder.visit_expr(&lambda.body);
 
     let free_vars = finder.free_vars();
-    let substitutions: HashMap<_, _> = free_vars
+    let substitutions: FxHashMap<_, _> = free_vars
         .iter()
         .map(|&id| (id, assigner.next_node()))
         .collect();