perf(es/parser): Optimize next_token (#10654)

Author: bvanjoi

.changeset/four-camels-sneeze.md

@@ -0,0 +1,6 @@
+---
+swc_core: patch
+swc_ecma_lexer: patch
+---
+
+less compute in next token

crates/swc_common/src/input.rs

@@ -56,6 +56,7 @@ impl<'a> StringInput<'a> {
  self.orig_start
  }
 
+ #[inline(always)]
  pub fn end_pos(&self) -> BytePos {
  self.orig_end
  }

crates/swc_ecma_lexer/src/lexer/state.rs

@@ -759,15 +759,11 @@ impl Lexer<'_> {
  *start = self.input.cur_pos();
  };
 
- match self.input.cur() {
- Some(..) => {}
+ if self.input.last_pos() == self.input.end_pos() {
  // End of input.
- None => {
- self.consume_pending_comments();
-
- return Ok(None);
- }
- };
+ self.consume_pending_comments();
+ return Ok(None);
+ }
 
  // println!(
  // "\tContext: ({:?}) {:?}",

crates/swc_ecma_parser/src/lexer/state.rs

@@ -378,15 +378,11 @@ impl Lexer<'_> {
  self.skip_space::<true>();
  *start = self.input.cur_pos();
 
- match self.input.cur() {
- Some(..) => {}
+ if self.input.last_pos() == self.input.end_pos() {
  // End of input.
- None => {
- self.consume_pending_comments();
-
- return Ok(None);
- }
- };
+ self.consume_pending_comments();
+ return Ok(None);
+ }
 
  // println!(
  // "\tContext: ({:?}) {:?}",