Importing rustc-1.49.0
Bug: 176888219
Change-Id: Ib0805d37e7b485cd420bbff8a8b000cf87e7ede0
diff --git a/compiler/rustc_lexer/src/lib.rs b/compiler/rustc_lexer/src/lib.rs
index d784a86..6539419 100644
--- a/compiler/rustc_lexer/src/lib.rs
+++ b/compiler/rustc_lexer/src/lib.rs
@@ -48,6 +48,7 @@
}
/// Enum representing common lexeme types.
+// perf note: Changing all `usize` to `u32` doesn't change performance. See #77629
#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord)]
pub enum TokenKind {
// Multi-char tokens:
@@ -160,6 +161,7 @@
/// - `r##~"abcde"##`: `InvalidStarter`
/// - `r###"abcde"##`: `NoTerminator { expected: 3, found: 2, possible_terminator_offset: Some(11)`
/// - Too many `#`s (>65535): `TooManyDelimiters`
+// perf note: It doesn't matter that this makes `Token` 36 bytes bigger. See #77629
#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord)]
pub enum RawStrError {
/// Non `#` characters exist between `r` and `"` eg. `r#~"..`
@@ -236,9 +238,10 @@
// Note that this set is stable (ie, it doesn't change with different
// Unicode versions), so it's ok to just hard-code the values.
- match c {
+ matches!(
+ c,
// Usual ASCII suspects
- | '\u{0009}' // \t
+ '\u{0009}' // \t
| '\u{000A}' // \n
| '\u{000B}' // vertical tab
| '\u{000C}' // form feed
@@ -255,9 +258,7 @@
// Dedicated whitespace characters from Unicode
| '\u{2028}' // LINE SEPARATOR
| '\u{2029}' // PARAGRAPH SEPARATOR
- => true,
- _ => false,
- }
+ )
}
/// True if `c` is valid as a first character of an identifier.
@@ -689,7 +690,12 @@
let mut max_hashes = 0;
// Count opening '#' symbols.
- let n_start_hashes = self.eat_while(|c| c == '#');
+ let mut eaten = 0;
+ while self.first() == '#' {
+ eaten += 1;
+ self.bump();
+ }
+ let n_start_hashes = eaten;
// Check that string is started.
match self.bump() {
@@ -724,16 +730,11 @@
// Note that this will not consume extra trailing `#` characters:
// `r###"abcde"####` is lexed as a `RawStr { n_hashes: 3 }`
// followed by a `#` token.
- let mut hashes_left = n_start_hashes;
- let is_closing_hash = |c| {
- if c == '#' && hashes_left != 0 {
- hashes_left -= 1;
- true
- } else {
- false
- }
- };
- let n_end_hashes = self.eat_while(is_closing_hash);
+ let mut n_end_hashes = 0;
+ while self.first() == '#' && n_end_hashes < n_start_hashes {
+ n_end_hashes += 1;
+ self.bump();
+ }
if n_end_hashes == n_start_hashes {
return (n_start_hashes, None);
@@ -807,17 +808,9 @@
}
/// Eats symbols while predicate returns true or until the end of file is reached.
- /// Returns amount of eaten symbols.
- fn eat_while<F>(&mut self, mut predicate: F) -> usize
- where
- F: FnMut(char) -> bool,
- {
- let mut eaten: usize = 0;
+ fn eat_while(&mut self, mut predicate: impl FnMut(char) -> bool) {
while predicate(self.first()) && !self.is_eof() {
- eaten += 1;
self.bump();
}
-
- eaten
}
}
