perf(atoms): Replace string-cache with hstr (#8126)

**Description:** `hstr` is an alternative for `string-cache` which does not support static strings and does not use a global mutex. **Related issue:** - Closes #4946. - Closes #7974.
2024-10-04 04:07:18 +03:00 · 2023-11-07 09:51:43 +09:00 · 2023-11-07 09:51:43 +09:00 · aa22746d03
commit aa22746d03
parent d1c6d6ea7b
11 changed files with 138 additions and 140 deletions
--- a/Cargo.lock
+++ b/Cargo.lock
@ -1037,12 +1037,12 @@ dependencies = [

 [[package]]
 name = "dashmap"
-version = "5.4.0"
+version = "5.5.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "907076dfda823b0b36d2a1bb5f90c96660a5bbcd7729e10727f07858f22c4edc"
+checksum = "978747c1d849a7d2ee5e8adc0159961c48fb7e5db2f06af6723b80123bb53856"
 dependencies = [
 "cfg-if",
- "hashbrown 0.12.3",
+ "hashbrown 0.14.1",
 "lock_api",
 "once_cell",
 "parking_lot_core",
@ -1634,6 +1634,20 @@ version = "0.4.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7f24254aa9a54b5c858eaee2f5bccdb46aaf0e486a595ed5fd8f86ba55232a70"

+[[package]]
+name = "hstr"
+version = "0.2.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d5700a2810cdc52f9a306f40c88031fac8d480f3d51ef38b9ca9ff5b8d4f3814"
+dependencies = [
+ "dashmap",
+ "new_debug_unreachable",
+ "once_cell",
+ "phf 0.11.2",
+ "rustc-hash",
+ "smallvec",
+]
+
 [[package]]
 name = "http"
 version = "0.2.9"
@ -3471,9 +3485,9 @@ checksum = "03b634d87b960ab1a38c4fe143b508576f075e7c978bfad18217645ebfdfa2ec"

 [[package]]
 name = "smallvec"
-version = "1.10.0"
+version = "1.11.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a507befe795404456341dfab10cef66ead4c041f62b8b11bbb92bffe5d0953e0"
+checksum = "942b4a808e05215192e39f4ab80813e599068285906cc91aa64f923db842bd5a"

 [[package]]
 name = "smartstring"
@ -3771,13 +3785,11 @@ name = "swc_atoms"
 version = "0.6.0"
 dependencies = [
 "bytecheck",
+ "hstr",
 "once_cell",
 "rkyv",
 "rustc-hash",
 "serde",
- "string_cache",
- "string_cache_codegen",
- "triomphe",
 ]

 [[package]]
@ -5870,16 +5882,6 @@ dependencies = [
 "tracing-log",
 ]

-[[package]]
-name = "triomphe"
-version = "0.1.8"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f1ee9bd9239c339d714d657fac840c6d2a4f9c45f4f9ec7b0975113458be78db"
-dependencies = [
- "serde",
- "stable_deref_trait",
-]
-
 [[package]]
 name = "try-lock"
 version = "0.2.4"
--- a/crates/swc_atoms/Cargo.toml
+++ b/crates/swc_atoms/Cargo.toml
@ -1,6 +1,5 @@
 [package]
 authors       = ["강동윤 <kdy1997.dev@gmail.com>"]
-build         = "build.rs"
 description   = "Atoms for the swc project."
 documentation = "https://rustdoc.swc.rs/swc_atoms/"
 edition       = "2021"
@ -19,6 +18,7 @@ rkyv-impl = ["__rkyv", "rkyv", "bytecheck"]
 [dependencies]
 # bytecheck version should be in sync with rkyv version. Do not bump individually.
 bytecheck = { version = "0.6.10", optional = true }
+hstr = "0.2.3"
 once_cell = "1"
 rkyv = { package = "rkyv", version = "=0.7.42", optional = true, features = [
  "strict",
@ -26,9 +26,3 @@ rkyv = { package = "rkyv", version = "=0.7.42", optional = true, features = [
 ] }
 rustc-hash = "1.1.0"
 serde = "1"
-string_cache = "0.8.7"
-triomphe = "0.1.8"
-
-
-[build-dependencies]
-string_cache_codegen = "0.5.2"
--- a/crates/swc_atoms/build.rs
+++ b/crates/swc_atoms/build.rs
@ -1,29 +0,0 @@
-use std::{env, path::Path};
-
-fn main() {
-    let strs = include_str!("words.txt")
-        .lines()
-        .map(|l| l.trim())
-        .collect::<Vec<_>>();
-    gen("internal_word", "InternalWord", &strs);
-}
-
-fn gen(mac_name: &str, type_name: &str, atoms: &[&str]) {
-    string_cache_codegen::AtomType::new(type_name, &format!("{}!", mac_name))
-        .atoms(atoms)
-        .with_atom_doc(
-            "
-[JsWord] is an interned string.
-
-This type should be used instead of [String] for values, because lots of
-values are duplicated. For example, if an identifier is named `myVariable`,
-there will be lots of identifier usages with the value `myVariable`.
-
-This type
-  - makes equality comparison faster.
-  - reduces memory usage.
-            ",
-        )
-        .write_to_file(&Path::new(&env::var("OUT_DIR").unwrap()).join(format!("{}.rs", mac_name)))
-        .unwrap();
-}
--- a/crates/swc_atoms/src/lib.rs
+++ b/crates/swc_atoms/src/lib.rs
@ -26,7 +26,7 @@ pub use self::{atom as js_word, Atom as JsWord};
 #[derive(Clone, Default)]
 #[cfg_attr(feature = "rkyv-impl", derive(rkyv::bytecheck::CheckBytes))]
 #[cfg_attr(feature = "rkyv-impl", repr(C))]
-pub struct Atom(string_cache::Atom<InternalWordStaticSet>);
+pub struct Atom(hstr::Atom);

 /// Safety: We do not perform slicing of single [Atom] from multiple threads.
 /// In other words, typically [Atom] is created in a single thread (and in the
@ -39,11 +39,11 @@ unsafe impl Sync for Atom {}

 impl Atom {
    /// Creates a new [Atom] from a string.
-    pub fn new<S>(s: S) -> Self
+    pub fn new<'i, S>(s: S) -> Self
    where
-        S: AsRef<str>,
+        S: Into<Cow<'i, str>>,
    {
-        Atom(s.as_ref().into())
+        Atom(hstr::Atom::from(s.into()))
    }

    #[inline]
@ -52,9 +52,6 @@ impl Atom {
    }
 }

-/// API wrappers for [tendril].
-impl Atom {}
-
 impl Deref for Atom {
    type Target = str;

@ -236,9 +233,17 @@ where
 #[doc(hidden)]
 pub type CahcedAtom = Lazy<Atom>;

-include!(concat!(env!("OUT_DIR"), "/internal_word.rs"));
-
 /// This should be used as a key for hash maps and hash sets.
 ///
 /// This will be replaced with [Atom] in the future.
-pub type StaticString = String;
+pub type StaticString = Atom;
+
+#[derive(Default)]
+pub struct AtomStore(hstr::AtomStore);
+
+impl AtomStore {
+    #[inline]
+    pub fn atom<'a>(&mut self, s: impl Into<Cow<'a, str>>) -> Atom {
+        Atom(self.0.atom(s))
+    }
+}
--- a/crates/swc_css_minifier/src/compressor/color.rs
+++ b/crates/swc_css_minifier/src/compressor/color.rs
@ -351,12 +351,12 @@ impl Compressor {
                value,
                span,
                ..
-            })) => match &*value.to_ascii_lowercase() {
-                "transparent" => {
+            })) => match value.to_ascii_lowercase() {
+                ref s if *s == "transparent" => {
                    *color = make_color!(*span, 0.0_f64, 0.0_f64, 0.0_f64, 0.0_f64);
                }
                name => {
-                    if let Some(value) = NAMED_COLORS.get(name) {
+                    if let Some(value) = NAMED_COLORS.get(&name) {
                        *color = make_color!(
                            *span,
                            value.rgb[0] as f64,
--- a/crates/swc_css_prefixer/src/prefixer.rs
+++ b/crates/swc_css_prefixer/src/prefixer.rs
@ -5,7 +5,7 @@ use std::mem::take;

 use once_cell::sync::Lazy;
 use preset_env_base::{query::targets_to_versions, version::Version, BrowserData, Versions};
-use swc_atoms::{JsWord, StaticString};
+use swc_atoms::JsWord;
 use swc_common::{collections::AHashMap, EqIgnoreSpan, DUMMY_SP};
 use swc_css_ast::*;
 use swc_css_utils::{
@ -16,9 +16,9 @@ use swc_css_visit::{VisitMut, VisitMutWith};

 use crate::options::Options;

-static PREFIXES_AND_BROWSERS: Lazy<AHashMap<StaticString, [BrowserData<Option<Version>>; 2]>> =
+static PREFIXES_AND_BROWSERS: Lazy<AHashMap<String, [BrowserData<Option<Version>>; 2]>> =
    Lazy::new(|| {
-        let map: AHashMap<StaticString, [BrowserData<Option<Version>>; 2]> =
+        let map: AHashMap<String, [BrowserData<Option<Version>>; 2]> =
            serde_json::from_str(include_str!("../data/prefixes_and_browsers.json"))
                .expect("failed to parse json");

--- a/crates/swc_ecma_parser/src/lexer/jsx.rs
+++ b/crates/swc_ecma_parser/src/lexer/jsx.rs
@ -1,5 +1,4 @@
 use either::Either;
-use swc_atoms::Atom;

 use super::*;
 use crate::token::Token;
@ -48,7 +47,7 @@ impl<'a> Lexer<'a> {
                    });

                    return Ok(Some(Token::JSXText {
-                        raw: Atom::new(out),
+                        raw: self.atoms.borrow_mut().atom(out),
                    }));
                }
                '>' => {
@ -323,9 +322,10 @@ impl<'a> Lexer<'a> {

        raw.push(quote);

+        let mut b = self.atoms.borrow_mut();
        Ok(Token::Str {
-            value: out.into(),
-            raw: Atom::new(raw),
+            value: b.atom(out),
+            raw: b.atom(raw),
        })
    }

@ -350,7 +350,9 @@ impl<'a> Lexer<'a> {
            }
        });

-        Ok(Token::JSXName { name: slice.into() })
+        Ok(Token::JSXName {
+            name: self.atoms.borrow_mut().atom(slice),
+        })
    }
 }

--- a/crates/swc_ecma_parser/src/lexer/mod.rs
+++ b/crates/swc_ecma_parser/src/lexer/mod.rs
@ -5,7 +5,7 @@ use std::{cell::RefCell, char, iter::FusedIterator, rc::Rc};
 use either::Either::{Left, Right};
 use smallvec::{smallvec, SmallVec};
 use smartstring::SmartString;
-use swc_atoms::Atom;
+use swc_atoms::{Atom, AtomStore};
 use swc_common::{comments::Comments, input::StringInput, BytePos, Span};
 use swc_ecma_ast::{op, AssignOp, EsVersion};

@ -132,6 +132,8 @@ pub struct Lexer<'a> {
    module_errors: Rc<RefCell<Vec<Error>>>,

    buf: Rc<RefCell<String>>,
+
+    atoms: Rc<RefCell<AtomStore>>,
 }

 impl FusedIterator for Lexer<'_> {}
@ -157,6 +159,7 @@ impl<'a> Lexer<'a> {
            errors: Default::default(),
            module_errors: Default::default(),
            buf: Rc::new(RefCell::new(String::with_capacity(256))),
+            atoms: Default::default(),
        }
    }

@ -764,8 +767,10 @@ impl<'a> Lexer<'a> {
    fn read_ident_unknown(&mut self) -> LexResult<Token> {
        debug_assert!(self.cur().is_some());

-        let (word, _) =
-            self.read_word_as_str_with(|s, _, _| Word::Ident(IdentLike::Other(s.into())))?;
+        let atoms = self.atoms.clone();
+        let (word, _) = self.read_word_as_str_with(|s, _, _| {
+            Word::Ident(IdentLike::Other(atoms.borrow_mut().atom(s)))
+        })?;

        Ok(Word(word))
    }
@ -778,6 +783,8 @@ impl<'a> Lexer<'a> {
    ) -> LexResult<Option<Token>> {
        debug_assert!(self.cur().is_some());

+        let atoms = self.atoms.clone();
+
        let start = self.cur_pos();
        let (word, has_escape) = self.read_word_as_str_with(|s, _, can_be_known| {
            if can_be_known {
@ -786,7 +793,7 @@ impl<'a> Lexer<'a> {
                }
            }

-            Word::Ident(IdentLike::Other(s.into()))
+            Word::Ident(IdentLike::Other(atoms.borrow_mut().atom(s)))
        })?;

        // Note: ctx is store in lexer because of this error.
@ -1000,6 +1007,7 @@ impl<'a> Lexer<'a> {

        self.bump(); // '"'

+        let atoms = self.atoms.clone();
        self.with_buf(|l, out| {
            while let Some(c) = {
                // Optimization
@ -1018,9 +1026,10 @@ impl<'a> Lexer<'a> {

                        l.bump();

+                        let mut b = atoms.borrow_mut();
                        return Ok(Token::Str {
-                            value: (&**out).into(),
-                            raw: raw.into(),
+                            value: b.atom(&*out),
+                            raw: b.atom(raw),
                        });
                    }
                    '\\' => {
@ -1052,9 +1061,10 @@ impl<'a> Lexer<'a> {

            l.emit_error(start, SyntaxError::UnterminatedStrLit);

+            let mut b = atoms.borrow_mut();
            Ok(Token::Str {
-                value: (&**out).into(),
-                raw: raw.into(),
+                value: b.atom(&*out),
+                raw: b.atom(raw),
            })
        })
    }
@ -1074,6 +1084,8 @@ impl<'a> Lexer<'a> {

        let (mut escaped, mut in_class) = (false, false);

+        let atoms = self.atoms.clone();
+
        let content = self.with_buf(|l, buf| {
            while let Some(c) = l.cur() {
                // This is ported from babel.
@ -1102,7 +1114,7 @@ impl<'a> Lexer<'a> {
                buf.push(c);
            }

-            Ok(Atom::new(&**buf))
+            Ok(atoms.borrow_mut().atom(&**buf))
        })?;

        // input is terminated without following `/`
@ -1122,9 +1134,9 @@ impl<'a> Lexer<'a> {
        // let flags_start = self.cur_pos();
        let flags = {
            match self.cur() {
-                Some(c) if c.is_ident_start() => {
-                    self.read_word_as_str_with(|s, _, _| s.into()).map(Some)
-                }
+                Some(c) if c.is_ident_start() => self
+                    .read_word_as_str_with(|s, _, _| atoms.borrow_mut().atom(s))
+                    .map(Some),
                _ => Ok(None),
            }
        }?
@ -1145,7 +1157,7 @@ impl<'a> Lexer<'a> {
            self.input.bump();
        }
        let s = self.input.uncons_while(|c| !c.is_line_terminator());
-        Ok(Some(Atom::new(s)))
+        Ok(Some(self.atoms.borrow_mut().atom(s)))
    }

    fn read_tmpl_token(&mut self, start_of_tpl: BytePos) -> LexResult<Token> {
@ -1170,7 +1182,7 @@ impl<'a> Lexer<'a> {
                // TODO: Handle error
                return Ok(Token::Template {
                    cooked: cooked.map(Atom::from),
-                    raw: Atom::new(&*raw),
+                    raw: self.atoms.borrow_mut().atom(&*raw),
                });
            }

--- a/crates/swc_ecma_parser/src/lexer/number.rs
+++ b/crates/swc_ecma_parser/src/lexer/number.rs
@ -62,7 +62,10 @@ impl<'a> Lexer<'a> {
            if self.eat(b'n') {
                raw.push('n');

-                return Ok(Either::Right((Box::new(s.into_value()), (&*raw).into())));
+                return Ok(Either::Right((
+                    Box::new(s.into_value()),
+                    self.atoms.borrow_mut().atom(&*raw),
+                )));
            }

            write!(raw_val, "{}", &s.value).unwrap();
@ -81,9 +84,9 @@ impl<'a> Lexer<'a> {
                    // e.g. `000` is octal
                    if start.0 != self.last_pos().0 - 1 {
                        // `-1` is utf 8 length of `0`
-                        return self
-                            .make_legacy_octal(start, 0f64)
-                            .map(|value| Either::Left((value, (&*raw).into())));
+                        return self.make_legacy_octal(start, 0f64).map(|value| {
+                            Either::Left((value, self.atoms.borrow_mut().atom(&*raw)))
+                        });
                    }
                } else {
                    // strict mode hates non-zero decimals starting with zero.
@ -110,9 +113,9 @@ impl<'a> Lexer<'a> {
                                    panic!("failed to parse {} into float using BigInt", val_str)
                                });

-                            return self
-                                .make_legacy_octal(start, val)
-                                .map(|value| Either::Left((value, (&*raw).into())));
+                            return self.make_legacy_octal(start, val).map(|value| {
+                                Either::Left((value, self.atoms.borrow_mut().atom(&*raw)))
+                            });
                        }
                    }
                }
@ -224,7 +227,7 @@ impl<'a> Lexer<'a> {

        self.ensure_not_ident()?;

-        Ok(Either::Left((val, (&*raw_str).into())))
+        Ok(Either::Left((val, self.atoms.borrow_mut().atom(&*raw_str))))
    }

    /// Returns `Left(value)` or `Right(BigInt)`
@ -238,6 +241,7 @@ impl<'a> Lexer<'a> {
        );
        debug_assert_eq!(self.cur(), Some('0'));

+        let atoms = self.atoms.clone();
        self.with_buf(|l, buf| {
            l.bump();

@ -263,12 +267,15 @@ impl<'a> Lexer<'a> {
            if l.eat(b'n') {
                buf.push('n');

-                return Ok(Either::Right((Box::new(s.into_value()), (&**buf).into())));
+                return Ok(Either::Right((
+                    Box::new(s.into_value()),
+                    atoms.borrow_mut().atom(&**buf),
+                )));
            }

            l.ensure_not_ident()?;

-            Ok(Either::Left((val, (&**buf).into())))
+            Ok(Either::Left((val, atoms.borrow_mut().atom(&**buf))))
        })
    }

--- a/crates/swc_ecma_parser/src/lexer/util.rs
+++ b/crates/swc_ecma_parser/src/lexer/util.rs
@ -257,7 +257,7 @@ impl<'a> Lexer<'a> {
            let cmt = Comment {
                kind: CommentKind::Line,
                span: Span::new(start, end, SyntaxContext::empty()),
-                text: s.into(),
+                text: self.atoms.borrow_mut().atom(s),
            };

            if is_for_next {
@ -343,7 +343,7 @@ impl<'a> Lexer<'a> {
            let cmt = Comment {
                kind: CommentKind::Block,
                span: Span::new(start, end, SyntaxContext::empty()),
-                text: s.into(),
+                text: self.atoms.borrow_mut().atom(s),
            };

            let _ = self.input.peek();
--- a/crates/swc_ecma_parser/src/token.rs
+++ b/crates/swc_ecma_parser/src/token.rs
@ -7,7 +7,7 @@ use std::{
 };

 use num_bigint::BigInt as BigIntValue;
-use swc_atoms::{atom, Atom, JsWord};
+use swc_atoms::{atom, Atom, AtomStore, JsWord};
 use swc_common::{Span, Spanned};
 use swc_ecma_ast::{AssignOp, BinaryOp};

@ -504,38 +504,25 @@ pub enum IdentLike {
    Other(JsWord),
 }

+impl From<&'_ str> for IdentLike {
+    fn from(s: &str) -> Self {
+        s.parse::<KnownIdent>()
+            .map(Self::Known)
+            .unwrap_or_else(|_| Self::Other(s.into()))
+    }
+}
+
+impl IdentLike {
+    pub(crate) fn from_str(atoms: &mut AtomStore, s: &str) -> IdentLike {
+        s.parse::<KnownIdent>()
+            .map(Self::Known)
+            .unwrap_or_else(|_| Self::Other(atoms.atom(s)))
+    }
+}
+
 impl Word {
-    pub(crate) fn kind(&self) -> WordKind {
-        match self {
-            Word::Keyword(k) => WordKind::Keyword(*k),
-            Word::Null => WordKind::Null,
-            Word::True => WordKind::True,
-            Word::False => WordKind::False,
-            Word::Ident(IdentLike::Known(i)) => WordKind::Ident(IdentKind::Known(*i)),
-            Word::Ident(IdentLike::Other(..)) => WordKind::Ident(IdentKind::Other),
-        }
-    }
-}
-
-impl WordKind {
-    pub(crate) const fn before_expr(self) -> bool {
-        match self {
-            Self::Keyword(k) => k.before_expr(),
-            _ => false,
-        }
-    }
-
-    pub(crate) const fn starts_expr(self) -> bool {
-        match self {
-            Self::Keyword(k) => k.starts_expr(),
-            _ => true,
-        }
-    }
-}
-
-impl From<&'_ str> for Word {
-    fn from(i: &str) -> Self {
-        match i {
+    pub fn from_str(atoms: &mut AtomStore, s: &str) -> Self {
+        match s {
            "null" => Word::Null,
            "true" => Word::True,
            "false" => Word::False,
@ -574,17 +561,35 @@ impl From<&'_ str> for Word {
            "typeof" => TypeOf.into(),
            "void" => Void.into(),
            "delete" => Delete.into(),
-            _ => Word::Ident(i.into()),
+            _ => Word::Ident(IdentLike::from_str(atoms, s)),
+        }
+    }
+
+    pub(crate) fn kind(&self) -> WordKind {
+        match self {
+            Word::Keyword(k) => WordKind::Keyword(*k),
+            Word::Null => WordKind::Null,
+            Word::True => WordKind::True,
+            Word::False => WordKind::False,
+            Word::Ident(IdentLike::Known(i)) => WordKind::Ident(IdentKind::Known(*i)),
+            Word::Ident(IdentLike::Other(..)) => WordKind::Ident(IdentKind::Other),
        }
    }
 }

-impl From<&'_ str> for IdentLike {
-    #[inline]
-    fn from(s: &str) -> Self {
-        s.parse::<KnownIdent>()
-            .map(Self::Known)
-            .unwrap_or_else(|_| Self::Other(s.into()))
+impl WordKind {
+    pub(crate) const fn before_expr(self) -> bool {
+        match self {
+            Self::Keyword(k) => k.before_expr(),
+            _ => false,
+        }
+    }
+
+    pub(crate) const fn starts_expr(self) -> bool {
+        match self {
+            Self::Keyword(k) => k.starts_expr(),
+            _ => true,
+        }
    }
 }