Function core_arch::x86::_mm_fnmadd_sd

pub unsafe fn _mm_fnmadd_sd(a: __m128d, b: __m128d, c: __m128d) -> __m128d

This is supported on x86 and target feature fma only.

Multiplies the lower double-precision (64-bit) floating-point elements in a and b, and add the negated intermediate result to the lower element in c. Store the result in the lower element of the returned value, and copy the upper element from a to the upper elements of the result.

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