Function core::arch::x86_64::_mm_cmpestra

pub unsafe fn _mm_cmpestra(
    a: __m128i, 
    la: i32, 
    b: __m128i, 
    lb: i32, 
    imm8: i32
) -> i32

This is supported on x86-64 and target feature sse4.2 only.

Compares packed strings in a and b with lengths la and lb using the control in imm8, and return 1 if b did not contain a null character and the resulting mask was zero, and 0 otherwise.

Intel's documentation