Function core::arch::x86_64::_mm_cmpestri

1.27.0 · source ·
pub unsafe fn _mm_cmpestri(
    a: __m128i,
    la: i32,
    b: __m128i,
    lb: i32,
    const IMM8: i32
) -> i32
Available on (x86 or x86-64) and target feature sse4.2 and x86-64 only.
Expand description

Compares packed strings a and b with lengths la and lb using the control in IMM8 and return the generated index. Similar to _mm_cmpistri with the exception that _mm_cmpistri implicitly determines the length of a and b.

§Control modes

The control specified by IMM8 may be one or more of the following.

§Data size and signedness

§Comparison options

§Result polarity

§Bit returned


#[cfg(target_arch = "x86")]
use std::arch::x86::*;
#[cfg(target_arch = "x86_64")]
use std::arch::x86_64::*;

// The string we want to find a substring in
let haystack = b"Split \r\n\t line  ";

// The string we want to search for with some
// extra bytes we do not want to search for.
let needle = b"\r\n\t ignore this ";

let a = _mm_loadu_si128(needle.as_ptr() as *const _);
let b = _mm_loadu_si128(haystack.as_ptr() as *const _);

// Note: We explicitly specify we only want to search `b` for the
// first 3 characters of a.
let idx = _mm_cmpestri(a, 3, b, 15, _SIDD_CMP_EQUAL_ORDERED);

assert_eq!(idx, 6);

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