vendor/memchr/src/memmem/prefilter/x86/avx.rs

   1 use core::arch::x86_64::__m256i;
   2
   3 use crate::memmem::{
   4     prefilter::{PrefilterFnTy, PrefilterState},
   5     NeedleInfo,
   6 };
   7
   8 // Check that the functions below satisfy the Prefilter function type.
   9 const _: PrefilterFnTy = find;
  10
  11 /// An AVX2 accelerated candidate finder for single-substring search.
  12 ///
  13 /// # Safety
  14 ///
  15 /// Callers must ensure that the avx2 CPU feature is enabled in the current
  16 /// environment.
  17 #[target_feature(enable = "avx2")]
  18 pub(crate) unsafe fn find(
  19     prestate: &mut PrefilterState,
  20     ninfo: &NeedleInfo,
  21     haystack: &[u8],
  22     needle: &[u8],
  23 ) -> Option<usize> {
  24     super::super::genericsimd::find::<__m256i>(
  25         prestate,
  26         ninfo,
  27         haystack,
  28         needle,
  29         super::sse::find,
  30     )
  31 }
  32
  33 #[cfg(test)]
  34 mod tests {
  35     #[test]
  36     #[cfg(not(miri))]
  37     fn prefilter_permutations() {
  38         use crate::memmem::prefilter::tests::PrefilterTest;
  39         if !is_x86_feature_detected!("avx2") {
  40             return;
  41         }
  42         // SAFETY: The safety of super::find only requires that the current
  43         // CPU support AVX2, which we checked above.
  44         unsafe { PrefilterTest::run_all_tests(super::find) };
  45     }
  46 }