js_parser: restore SIMD block comment skipping via Highway

scripts/verify-baseline-static/allowlist-aarch64.txt

@@ -5,7 +5,7 @@
 
 # ----------------------------------------------------------------------------
 # Bun's Highway SVE/SVE2 targets. Gate: hwy::SupportedTargets via getauxval(AT_HWCAP).
-# (80 symbols)
+# (84 symbols)
 # ----------------------------------------------------------------------------
 _ZN3bun10N_SVE2_12810MemMemImplEPKhmS2_m                                      [SVE]
 _ZN3bun10N_SVE2_12815CopyU16ToU8ImplEPKtmPh                                   [SVE]
@@ -26,6 +26,7 @@ _ZN3bun10N_SVE2_12836ContainsNewlineOrNonASCIIOrQuoteImplEPKhm                [S
 _ZN3bun10N_SVE2_12838IndexOfNewlineOrNonASCIIOrHashOrAtImplEPKhm              [SVE]
 _ZN3bun10N_SVE2_12846IndexOfInterestingCharacterInStringLiteralImplEPKhmh     [SVE]
 _ZN3bun10N_SVE2_12846IndexOfNeedsEscapeForJavaScriptStringImplQuoteEPKhmh     [SVE]
+_ZN3bun10N_SVE2_12849IndexOfInterestingCharacterInMultilineCommentImplEPKhm   [SVE]
 _ZN3bun10N_SVE2_12849IndexOfNeedsEscapeForJavaScriptStringImplBacktickEPKhmh  [SVE]
 _ZN3bun5N_SVE10MemMemImplEPKhmS2_m                                            [SVE]
 _ZN3bun5N_SVE15CopyU16ToU8ImplEPKtmPh                                         [SVE]
@@ -46,6 +47,7 @@ _ZN3bun5N_SVE36ContainsNewlineOrNonASCIIOrQuoteImplEPKhm                      [S
 _ZN3bun5N_SVE38IndexOfNewlineOrNonASCIIOrHashOrAtImplEPKhm                    [SVE]
 _ZN3bun5N_SVE46IndexOfInterestingCharacterInStringLiteralImplEPKhmh           [SVE]
 _ZN3bun5N_SVE46IndexOfNeedsEscapeForJavaScriptStringImplQuoteEPKhmh           [SVE]
+_ZN3bun5N_SVE49IndexOfInterestingCharacterInMultilineCommentImplEPKhm         [SVE]
 _ZN3bun5N_SVE49IndexOfNeedsEscapeForJavaScriptStringImplBacktickEPKhmh        [SVE]
 _ZN3bun6N_SVE210MemMemImplEPKhmS2_m                                           [SVE]
 _ZN3bun6N_SVE215CopyU16ToU8ImplEPKtmPh                                        [SVE]
@@ -66,6 +68,7 @@ _ZN3bun6N_SVE236ContainsNewlineOrNonASCIIOrQuoteImplEPKhm                     [S
 _ZN3bun6N_SVE238IndexOfNewlineOrNonASCIIOrHashOrAtImplEPKhm                   [SVE]
 _ZN3bun6N_SVE246IndexOfInterestingCharacterInStringLiteralImplEPKhmh          [SVE]
 _ZN3bun6N_SVE246IndexOfNeedsEscapeForJavaScriptStringImplQuoteEPKhmh          [SVE]
+_ZN3bun6N_SVE249IndexOfInterestingCharacterInMultilineCommentImplEPKhm        [SVE]
 _ZN3bun6N_SVE249IndexOfNeedsEscapeForJavaScriptStringImplBacktickEPKhmh       [SVE]
 _ZN3bun9N_SVE_25610MemMemImplEPKhmS2_m                                        [SVE]
 _ZN3bun9N_SVE_25615CopyU16ToU8ImplEPKtmPh                                     [SVE]
@@ -86,6 +89,7 @@ _ZN3bun9N_SVE_25636ContainsNewlineOrNonASCIIOrQuoteImplEPKhm                  [S
 _ZN3bun9N_SVE_25638IndexOfNewlineOrNonASCIIOrHashOrAtImplEPKhm                [SVE]
 _ZN3bun9N_SVE_25646IndexOfInterestingCharacterInStringLiteralImplEPKhmh       [SVE]
 _ZN3bun9N_SVE_25646IndexOfNeedsEscapeForJavaScriptStringImplQuoteEPKhmh       [SVE]
+_ZN3bun9N_SVE_25649IndexOfInterestingCharacterInMultilineCommentImplEPKhm     [SVE]
 _ZN3bun9N_SVE_25649IndexOfNeedsEscapeForJavaScriptStringImplBacktickEPKhmh    [SVE]
 
 

scripts/verify-baseline-static/allowlist-x64-windows.txt

@@ -437,7 +437,7 @@ ctiMasmProbeTrampolineAVX  [AVX]
 
 # ----------------------------------------------------------------------------
 # Highway. MSVC-mangled bun::N_AVX* names.
-# (120 symbols)
+# (126 symbols)
 # ----------------------------------------------------------------------------
 bun::N_AVX10_2::ContainsNewlineOrNonASCIIOrQuoteImpl                 [AVX, AVX512BW, AVX512F]
 bun::N_AVX10_2::CopyAsciiPrefixImpl                                  [AVX, AVX512BW, AVX512F, AVX512VL]
@@ -449,6 +449,7 @@ bun::N_AVX10_2::FirstNonAscii16Impl                                  [AVX, AVX51
 bun::N_AVX10_2::FirstNonAscii8Impl                                   [AVX, AVX512BW]
 bun::N_AVX10_2::IndexOfAnyCharImpl                                   [AVX, AVX512BW, AVX512F, AVX512VL, AVX512_FP16]
 bun::N_AVX10_2::IndexOfCharImpl                                      [AVX, AVX512BW, BMI2]
+bun::N_AVX10_2::IndexOfInterestingCharacterInMultilineCommentImpl    [AVX, AVX512BW, AVX512F]
 bun::N_AVX10_2::IndexOfInterestingCharacterInStringLiteralImpl       [AVX, AVX512BW, AVX512F]
 bun::N_AVX10_2::IndexOfNeedsEscapeForJavaScriptStringImplBacktick    [AVX, AVX512BW, AVX512F]
 bun::N_AVX10_2::IndexOfNeedsEscapeForJavaScriptStringImplQuote       [AVX, AVX512BW, AVX512F]
@@ -469,6 +470,7 @@ bun::N_AVX2::FirstNonAscii16Impl                                     [AVX, AVX2,
 bun::N_AVX2::FirstNonAscii8Impl                                      [AVX, AVX2]
 bun::N_AVX2::IndexOfAnyCharImpl                                      [AVX, AVX2]
 bun::N_AVX2::IndexOfCharImpl                                         [AVX, AVX2]
+bun::N_AVX2::IndexOfInterestingCharacterInMultilineCommentImpl       [AVX, AVX2]
 bun::N_AVX2::IndexOfInterestingCharacterInStringLiteralImpl          [AVX, AVX2]
 bun::N_AVX2::IndexOfNeedsEscapeForJavaScriptStringImplBacktick       [AVX, AVX2]
 bun::N_AVX2::IndexOfNeedsEscapeForJavaScriptStringImplQuote          [AVX, AVX2]
@@ -489,6 +491,7 @@ bun::N_AVX3::FirstNonAscii16Impl                                     [AVX, AVX51
 bun::N_AVX3::FirstNonAscii8Impl                                      [AVX, AVX512BW]
 bun::N_AVX3::IndexOfAnyCharImpl                                      [AVX, AVX512BW, AVX512F, AVX512VL]
 bun::N_AVX3::IndexOfCharImpl                                         [AVX, AVX512BW, BMI2]
+bun::N_AVX3::IndexOfInterestingCharacterInMultilineCommentImpl       [AVX, AVX512BW, AVX512F]
 bun::N_AVX3::IndexOfInterestingCharacterInStringLiteralImpl          [AVX, AVX512BW, AVX512F]
 bun::N_AVX3::IndexOfNeedsEscapeForJavaScriptStringImplBacktick       [AVX, AVX512BW, AVX512F]
 bun::N_AVX3::IndexOfNeedsEscapeForJavaScriptStringImplQuote          [AVX, AVX512BW, AVX512F]
@@ -509,6 +512,7 @@ bun::N_AVX3_DL::FirstNonAscii16Impl                                  [AVX, AVX51
 bun::N_AVX3_DL::FirstNonAscii8Impl                                   [AVX, AVX512BW]
 bun::N_AVX3_DL::IndexOfAnyCharImpl                                   [AVX, AVX512BW, AVX512F, AVX512VL]
 bun::N_AVX3_DL::IndexOfCharImpl                                      [AVX, AVX512BW, BMI2]
+bun::N_AVX3_DL::IndexOfInterestingCharacterInMultilineCommentImpl    [AVX, AVX512BW, AVX512F]
 bun::N_AVX3_DL::IndexOfInterestingCharacterInStringLiteralImpl       [AVX, AVX512BW, AVX512F]
 bun::N_AVX3_DL::IndexOfNeedsEscapeForJavaScriptStringImplBacktick    [AVX, AVX512BW, AVX512F]
 bun::N_AVX3_DL::IndexOfNeedsEscapeForJavaScriptStringImplQuote       [AVX, AVX512BW, AVX512F]
@@ -529,6 +533,7 @@ bun::N_AVX3_SPR::FirstNonAscii16Impl                                 [AVX, AVX51
 bun::N_AVX3_SPR::FirstNonAscii8Impl                                  [AVX, AVX512BW]
 bun::N_AVX3_SPR::IndexOfAnyCharImpl                                  [AVX, AVX512BW, AVX512F, AVX512VL, AVX512_FP16]
 bun::N_AVX3_SPR::IndexOfCharImpl                                     [AVX, AVX512BW, BMI2]
+bun::N_AVX3_SPR::IndexOfInterestingCharacterInMultilineCommentImpl   [AVX, AVX512BW, AVX512F]
 bun::N_AVX3_SPR::IndexOfInterestingCharacterInStringLiteralImpl      [AVX, AVX512BW, AVX512F]
 bun::N_AVX3_SPR::IndexOfNeedsEscapeForJavaScriptStringImplBacktick   [AVX, AVX512BW, AVX512F]
 bun::N_AVX3_SPR::IndexOfNeedsEscapeForJavaScriptStringImplQuote      [AVX, AVX512BW, AVX512F]
@@ -549,6 +554,7 @@ bun::N_AVX3_ZEN4::FirstNonAscii16Impl                                [AVX, AVX51
 bun::N_AVX3_ZEN4::FirstNonAscii8Impl                                 [AVX, AVX512BW]
 bun::N_AVX3_ZEN4::IndexOfAnyCharImpl                                 [AVX, AVX512BW, AVX512F, AVX512VL]
 bun::N_AVX3_ZEN4::IndexOfCharImpl                                    [AVX, AVX512BW, BMI2]
+bun::N_AVX3_ZEN4::IndexOfInterestingCharacterInMultilineCommentImpl  [AVX, AVX512BW, AVX512F]
 bun::N_AVX3_ZEN4::IndexOfInterestingCharacterInStringLiteralImpl     [AVX, AVX512BW, AVX512F]
 bun::N_AVX3_ZEN4::IndexOfNeedsEscapeForJavaScriptStringImplBacktick  [AVX, AVX512BW, AVX512F]
 bun::N_AVX3_ZEN4::IndexOfNeedsEscapeForJavaScriptStringImplQuote     [AVX, AVX512BW, AVX512F]

scripts/verify-baseline-static/allowlist-x64.txt

@@ -459,7 +459,7 @@ ctiMasmProbeTrampolineAVX  [AVX]
 
 # ----------------------------------------------------------------------------
 # Bun's Highway SIMD. Gate: HWY_DYNAMIC_DISPATCH via hwy::SupportedTargets.
-# (120 symbols)
+# (126 symbols)
 # ----------------------------------------------------------------------------
 _ZN3bun10N_AVX3_SPR10MemMemImplEPKhmS2_m                                       [AVX, AVX512BW, AVX512F, BMI1]
 _ZN3bun10N_AVX3_SPR15CopyU16ToU8ImplEPKtmPh                                    [AVX, AVX512BW, AVX512F, AVX512VL, AVX512_VBMI]
@@ -480,6 +480,7 @@ _ZN3bun10N_AVX3_SPR36ContainsNewlineOrNonASCIIOrQuoteImplEPKhm                 [
 _ZN3bun10N_AVX3_SPR38IndexOfNewlineOrNonASCIIOrHashOrAtImplEPKhm               [AVX, AVX512BW, AVX512F]
 _ZN3bun10N_AVX3_SPR46IndexOfInterestingCharacterInStringLiteralImplEPKhmh      [AVX, AVX512BW, AVX512F]
 _ZN3bun10N_AVX3_SPR46IndexOfNeedsEscapeForJavaScriptStringImplQuoteEPKhmh      [AVX, AVX512BW, AVX512F]
+_ZN3bun10N_AVX3_SPR49IndexOfInterestingCharacterInMultilineCommentImplEPKhm    [AVX, AVX512BW, AVX512F]
 _ZN3bun10N_AVX3_SPR49IndexOfNeedsEscapeForJavaScriptStringImplBacktickEPKhmh   [AVX, AVX512BW, AVX512F]
 _ZN3bun11N_AVX3_ZEN410MemMemImplEPKhmS2_m                                      [AVX, AVX512BW, AVX512F, BMI1]
 _ZN3bun11N_AVX3_ZEN415CopyU16ToU8ImplEPKtmPh                                   [AVX, AVX512BW, AVX512F, AVX512VL, AVX512_VBMI]
@@ -500,6 +501,7 @@ _ZN3bun11N_AVX3_ZEN436ContainsNewlineOrNonASCIIOrQuoteImplEPKhm                [
 _ZN3bun11N_AVX3_ZEN438IndexOfNewlineOrNonASCIIOrHashOrAtImplEPKhm              [AVX, AVX512BW, AVX512F]
 _ZN3bun11N_AVX3_ZEN446IndexOfInterestingCharacterInStringLiteralImplEPKhmh     [AVX, AVX512BW, AVX512F]
 _ZN3bun11N_AVX3_ZEN446IndexOfNeedsEscapeForJavaScriptStringImplQuoteEPKhmh     [AVX, AVX512BW, AVX512F]
+_ZN3bun11N_AVX3_ZEN449IndexOfInterestingCharacterInMultilineCommentImplEPKhm   [AVX, AVX512BW, AVX512F]
 _ZN3bun11N_AVX3_ZEN449IndexOfNeedsEscapeForJavaScriptStringImplBacktickEPKhmh  [AVX, AVX512BW, AVX512F]
 _ZN3bun6N_AVX210MemMemImplEPKhmS2_m                                            [AVX, AVX2]
 _ZN3bun6N_AVX215CopyU16ToU8ImplEPKtmPh                                         [AVX, AVX2]
@@ -520,6 +522,7 @@ _ZN3bun6N_AVX236ContainsNewlineOrNonASCIIOrQuoteImplEPKhm                      [
 _ZN3bun6N_AVX238IndexOfNewlineOrNonASCIIOrHashOrAtImplEPKhm                    [AVX, AVX2]
 _ZN3bun6N_AVX246IndexOfInterestingCharacterInStringLiteralImplEPKhmh           [AVX, AVX2]
 _ZN3bun6N_AVX246IndexOfNeedsEscapeForJavaScriptStringImplQuoteEPKhmh           [AVX, AVX2]
+_ZN3bun6N_AVX249IndexOfInterestingCharacterInMultilineCommentImplEPKhm         [AVX, AVX2]
 _ZN3bun6N_AVX249IndexOfNeedsEscapeForJavaScriptStringImplBacktickEPKhmh        [AVX, AVX2]
 _ZN3bun6N_AVX310MemMemImplEPKhmS2_m                                            [AVX, AVX512BW, AVX512F, BMI1]
 _ZN3bun6N_AVX315CopyU16ToU8ImplEPKtmPh                                         [AVX, AVX512BW, AVX512F, AVX512VL]
@@ -540,6 +543,7 @@ _ZN3bun6N_AVX336ContainsNewlineOrNonASCIIOrQuoteImplEPKhm                      [
 _ZN3bun6N_AVX338IndexOfNewlineOrNonASCIIOrHashOrAtImplEPKhm                    [AVX, AVX512BW, AVX512F]
 _ZN3bun6N_AVX346IndexOfInterestingCharacterInStringLiteralImplEPKhmh           [AVX, AVX512BW, AVX512F]
 _ZN3bun6N_AVX346IndexOfNeedsEscapeForJavaScriptStringImplQuoteEPKhmh           [AVX, AVX512BW, AVX512F]
+_ZN3bun6N_AVX349IndexOfInterestingCharacterInMultilineCommentImplEPKhm         [AVX, AVX512BW, AVX512F]
 _ZN3bun6N_AVX349IndexOfNeedsEscapeForJavaScriptStringImplBacktickEPKhmh        [AVX, AVX512BW, AVX512F]
 _ZN3bun9N_AVX10_210MemMemImplEPKhmS2_m                                         [AVX, AVX512BW, AVX512F, BMI1]
 _ZN3bun9N_AVX10_215CopyU16ToU8ImplEPKtmPh                                      [AVX, AVX512BW, AVX512F, AVX512VL, AVX512_VBMI]
@@ -560,6 +564,7 @@ _ZN3bun9N_AVX10_236ContainsNewlineOrNonASCIIOrQuoteImplEPKhm                   [
 _ZN3bun9N_AVX10_238IndexOfNewlineOrNonASCIIOrHashOrAtImplEPKhm                 [AVX, AVX512BW, AVX512F]
 _ZN3bun9N_AVX10_246IndexOfInterestingCharacterInStringLiteralImplEPKhmh        [AVX, AVX512BW, AVX512F]
 _ZN3bun9N_AVX10_246IndexOfNeedsEscapeForJavaScriptStringImplQuoteEPKhmh        [AVX, AVX512BW, AVX512F]
+_ZN3bun9N_AVX10_249IndexOfInterestingCharacterInMultilineCommentImplEPKhm      [AVX, AVX512BW, AVX512F]
 _ZN3bun9N_AVX10_249IndexOfNeedsEscapeForJavaScriptStringImplBacktickEPKhmh     [AVX, AVX512BW, AVX512F]
 _ZN3bun9N_AVX3_DL10MemMemImplEPKhmS2_m                                         [AVX, AVX512BW, AVX512F, BMI1]
 _ZN3bun9N_AVX3_DL15CopyU16ToU8ImplEPKtmPh                                      [AVX, AVX512BW, AVX512F, AVX512VL, AVX512_VBMI]
@@ -580,6 +585,7 @@ _ZN3bun9N_AVX3_DL36ContainsNewlineOrNonASCIIOrQuoteImplEPKhm                   [
 _ZN3bun9N_AVX3_DL38IndexOfNewlineOrNonASCIIOrHashOrAtImplEPKhm                 [AVX, AVX512BW, AVX512F]
 _ZN3bun9N_AVX3_DL46IndexOfInterestingCharacterInStringLiteralImplEPKhmh        [AVX, AVX512BW, AVX512F]
 _ZN3bun9N_AVX3_DL46IndexOfNeedsEscapeForJavaScriptStringImplQuoteEPKhmh        [AVX, AVX512BW, AVX512F]
+_ZN3bun9N_AVX3_DL49IndexOfInterestingCharacterInMultilineCommentImplEPKhm      [AVX, AVX512BW, AVX512F]
 _ZN3bun9N_AVX3_DL49IndexOfNeedsEscapeForJavaScriptStringImplBacktickEPKhmh     [AVX, AVX512BW, AVX512F]
 
 

src/highway/lib.rs

@@ -12,6 +12,11 @@ unsafe extern "C" {
         quote: u8,
     ) -> usize;
 
+    fn highway_index_of_interesting_character_in_multiline_comment(
+        text: *const u8,
+        text_len: usize,
+    ) -> usize;
+
     fn highway_index_of_newline_or_non_ascii(haystack: *const u8, haystack_len: usize) -> usize;
 
     fn highway_index_of_newline_or_non_ascii_or_hash_or_at(
@@ -121,6 +126,41 @@ pub fn index_of_interesting_character_in_string_literal(
     Some(result)
 }
 
+/// Useful for scanning the body of `/* ... */` block comments.
+/// Scans for:
+/// - `*` (potential `*/` terminator)
+/// - `\n`, `\r`
+/// - Non-ASCII characters (so the caller decodes U+2028/U+2029 and other
+///   multi-byte sequences one code point at a time)
+#[inline(always)]
+pub fn index_of_interesting_character_in_multiline_comment(slice: &[u8]) -> Option<usize> {
+    if slice.is_empty() {
+        return None;
+    }
+
+    // SAFETY: slice.ptr/len are a valid readable range.
+    let result = unsafe {
+        highway_index_of_interesting_character_in_multiline_comment(slice.as_ptr(), slice.len())
+    };
+
+    if result == slice.len() {
+        return None;
+    }
+
+    if cfg!(debug_assertions) {
+        let haystack_char = slice[result];
+        if !(haystack_char > 127
+            || haystack_char == b'*'
+            || haystack_char == b'\r'
+            || haystack_char == b'\n')
+        {
+            panic!("Invalid character found in indexOfInterestingCharacterInMultilineComment");
+        }
+    }
+
+    Some(result)
+}
+
 #[inline(always)]
 pub fn index_of_newline_or_non_ascii(haystack: &[u8]) -> Option<usize> {
     debug_assert!(!haystack.is_empty());

src/js_parser/lexer.rs

@@ -2441,25 +2441,14 @@ lexer_impl_header! {
                     )?;
                 }
                 _ => {
-                    if Environment::ENABLE_SIMD {
-                        if self.code_point < 128 {
-                            let remainder = &contents[self.current..];
-                            if remainder.len() >= 512 {
-                                match skip_to_interesting_character_in_multiline_comment(
-                                    remainder,
-                                ) {
-                                    Some(off) => {
-                                        self.current += off as usize;
-                                        self.end = self.current.saturating_sub(1);
-                                        self.step_with(contents);
-                                        continue;
-                                    }
-                                    None => {
-                                        self.step_with(contents);
-                                        continue;
-                                    }
-                                }
-                            }
+                    if self.code_point < 128 {
+                        let remainder = &contents[self.current..];
+                        if remainder.len() >= 512 {
+                            self.current +=
+                                skip_to_interesting_character_in_multiline_comment(remainder);
+                            self.end = self.current.saturating_sub(1);
+                            self.step_with(contents);
+                            continue;
                         }
                     }
 
@@ -4158,29 +4147,14 @@ impl PragmaArg {
     }
 }
 
-fn skip_to_interesting_character_in_multiline_comment(text_: &[u8]) -> Option<u32> {
-    // PERF(port): Zig uses portable @Vector SIMD here. Rust port uses scalar; could
-    // swap to bun_highway or core::simd. Logic preserved (returns offset of first
-    // '*' / '\r' / '\n' / non-ASCII byte, truncated to chunks of `ascii_vector_size`).
-    // TODO(port): SIMD reimplementation
-    let vsize = strings::ASCII_VECTOR_SIZE;
-    let text_end_len = text_.len() & !(vsize - 1);
-    debug_assert!(text_end_len.is_multiple_of(vsize));
-    debug_assert!(text_end_len <= text_.len());
-
-    let mut off: usize = 0;
-    while off < text_end_len {
-        let chunk = &text_[off..off + vsize];
-        for (j, &b) in chunk.iter().enumerate() {
-            if b > 127 || b == b'*' || b == b'\r' || b == b'\n' {
-                debug_assert!(j < vsize);
-                return Some((off + j) as u32);
-            }
-        }
-        off += vsize;
-    }
-
-    Some(off as u32)
+/// Byte offset of the next character `scan_multi_line_comment_body` has to
+/// inspect one code point at a time: the first `*` (potential `*/`
+/// terminator), `\r` / `\n` (newline tracking for ASI), or non-ASCII byte
+/// (U+2028/U+2029 and other multi-byte sequences). Returns `text_.len()` when
+/// the rest of the input has no such byte — the comment is unterminated, so
+/// the caller's next `step()` lands on EOF and reports the error.
+fn skip_to_interesting_character_in_multiline_comment(text_: &[u8]) -> usize {
+    bun_highway::index_of_interesting_character_in_multiline_comment(text_).unwrap_or(text_.len())
 }
 
 fn index_of_interesting_character_in_string_literal(text_: &[u8], quote: u8) -> Option<usize> {