1 files changed, 142 insertions, 0 deletions
diff --git a/vendor/httparse/src/simd/sse42.rs b/vendor/httparse/src/simd/sse42.rs
new file mode 100644
index 00000000..0fabdfeb
--- /dev/null
+++ b/vendor/httparse/src/simd/sse42.rs
@@ -0,0 +1,142 @@
+use crate::iter::Bytes;
+
+#[target_feature(enable = "sse4.2")]
+pub unsafe fn match_uri_vectored(bytes: &mut Bytes) {
+    while bytes.as_ref().len() >= 16 {
+        let advance = match_url_char_16_sse(bytes.as_ref());
+
+        bytes.advance(advance);
+
+        if advance != 16 {
+            return;
+        }
+    }
+    super::swar::match_uri_vectored(bytes);
+}
+
+#[inline(always)]
+#[allow(non_snake_case)]
+unsafe fn match_url_char_16_sse(buf: &[u8]) -> usize {
+    debug_assert!(buf.len() >= 16);
+
+    #[cfg(target_arch = "x86")]
+    use core::arch::x86::*;
+    #[cfg(target_arch = "x86_64")]
+    use core::arch::x86_64::*;
+
+    let ptr = buf.as_ptr();
+
+    // %x21-%x7e %x80-%xff
+    let DEL: __m128i = _mm_set1_epi8(0x7f);
+    let LOW: __m128i = _mm_set1_epi8(0x21);
+
+    let dat = _mm_lddqu_si128(ptr as *const _);
+    // unsigned comparison dat >= LOW
+    let low = _mm_cmpeq_epi8(_mm_max_epu8(dat, LOW), dat);
+    let del = _mm_cmpeq_epi8(dat, DEL);
+    let bit = _mm_andnot_si128(del, low);
+    let res = _mm_movemask_epi8(bit) as u16;
+
+    // TODO: use .trailing_ones() once MSRV >= 1.46
+    (!res).trailing_zeros() as usize
+}
+
+#[target_feature(enable = "sse4.2")]
+pub unsafe fn match_header_value_vectored(bytes: &mut Bytes) {
+    while bytes.as_ref().len() >= 16 {
+        let advance = match_header_value_char_16_sse(bytes.as_ref());
+        bytes.advance(advance);
+
+       if advance != 16 {
+            return;
+       }
+    }
+    super::swar::match_header_value_vectored(bytes);
+}
+
+#[inline(always)]
+#[allow(non_snake_case)]
+unsafe fn match_header_value_char_16_sse(buf: &[u8]) -> usize {
+    debug_assert!(buf.len() >= 16);
+
+    #[cfg(target_arch = "x86")]
+    use core::arch::x86::*;
+    #[cfg(target_arch = "x86_64")]
+    use core::arch::x86_64::*;
+
+    let ptr = buf.as_ptr();
+
+    // %x09 %x20-%x7e %x80-%xff
+    let TAB: __m128i = _mm_set1_epi8(0x09);
+    let DEL: __m128i = _mm_set1_epi8(0x7f);
+    let LOW: __m128i = _mm_set1_epi8(0x20);
+
+    let dat = _mm_lddqu_si128(ptr as *const _);
+    // unsigned comparison dat >= LOW
+    let low = _mm_cmpeq_epi8(_mm_max_epu8(dat, LOW), dat);
+    let tab = _mm_cmpeq_epi8(dat, TAB);
+    let del = _mm_cmpeq_epi8(dat, DEL);
+    let bit = _mm_andnot_si128(del, _mm_or_si128(low, tab));
+    let res = _mm_movemask_epi8(bit) as u16;
+
+    // TODO: use .trailing_ones() once MSRV >= 1.46
+    (!res).trailing_zeros() as usize
+}
+
+#[test]
+fn sse_code_matches_uri_chars_table() {
+    if !is_x86_feature_detected!("sse4.2") {
+        return;
+    }
+
+    #[allow(clippy::undocumented_unsafe_blocks)]
+    unsafe {
+        assert!(byte_is_allowed(b'_', match_uri_vectored));
+
+        for (b, allowed) in crate::URI_MAP.iter().cloned().enumerate() {
+            assert_eq!(
+                byte_is_allowed(b as u8, match_uri_vectored), allowed,
+                "byte_is_allowed({:?}) should be {:?}", b, allowed,
+            );
+        }
+    }
+}
+
+#[test]
+fn sse_code_matches_header_value_chars_table() {
+    if !is_x86_feature_detected!("sse4.2") {
+        return;
+    }
+
+    #[allow(clippy::undocumented_unsafe_blocks)]
+    unsafe {
+        assert!(byte_is_allowed(b'_', match_header_value_vectored));
+
+        for (b, allowed) in crate::HEADER_VALUE_MAP.iter().cloned().enumerate() {
+            assert_eq!(
+                byte_is_allowed(b as u8, match_header_value_vectored), allowed,
+                "byte_is_allowed({:?}) should be {:?}", b, allowed,
+            );
+        }
+    }
+}
+
+#[allow(clippy::missing_safety_doc)]
+#[cfg(test)]
+unsafe fn byte_is_allowed(byte: u8, f: unsafe fn(bytes: &mut Bytes<'_>)) -> bool {
+    let slice = [
+        b'_', b'_', b'_', b'_',
+        b'_', b'_', b'_', b'_',
+        b'_', b'_', byte, b'_',
+        b'_', b'_', b'_', b'_',
+    ];
+    let mut bytes = Bytes::new(&slice);
+
+    f(&mut bytes);
+
+    match bytes.pos() {
+        16 => true,
+        10 => false,
+        _ => unreachable!(),
+    }
+}