Function _mm_cvtsd_ss

pub unsafe fn _mm_cvtsd_ss(a: __m128, b: __m128d) -> __m128

Available on (x86 or x86-64) and target feature sse2 and x86 only.

Converts the lower double-precision (64-bit) floating-point element in b to a single-precision (32-bit) floating-point element, store the result in the lower element of the return value, and copies the upper element from a to the upper element the return value.

Intel’s documentation