Available on x86 and target feature
sse4.1 only.Expand description
Multiplies the packed 32-bit integers in a and b, producing intermediate
64-bit integers, and returns the lowest 32-bit, whatever they might be,
reinterpreted as a signed integer. While pmulld __m128i::splat(2), __m128i::splat(2) returns the obvious __m128i::splat(4), due to wrapping
arithmetic pmulld __m128i::splat(i32::MAX), __m128i::splat(2) would
return a negative number.