Function core_arch::x86::_mm256_testz_pd

pub unsafe fn _mm256_testz_pd(a: __m256d, b: __m256d) -> i32

This is supported on x86 and target feature avx only.

Computes the bitwise AND of 256 bits (representing double-precision (64-bit) floating-point elements) in a and b, producing an intermediate 256-bit value, and set ZF to 1 if the sign bit of each 64-bit element in the intermediate value is zero, otherwise set ZF to 0. Compute the bitwise NOT of a and then AND with b, producing an intermediate value, and set CF to 1 if the sign bit of each 64-bit element in the intermediate value is zero, otherwise set CF to 0. Return the ZF value.

Intel's documentation