Function core::arch::x86_64::_mm_test_all_ones

pub unsafe fn _mm_test_all_ones(a: __m128i) -> i32

This is supported on x86-64 and target feature sse4.1 only.

Tests whether the specified bits in a 128-bit integer vector are all ones.

Argument:

• a - A 128-bit integer vector containing the bits to be tested.

Returns:

• 1 - if the bits specified in the operand are all set to 1,
• 0 - otherwise.

Intel's documentation