Function core::arch::x86_64::_mm_fnmadd_round_ss

pub unsafe fn _mm_fnmadd_round_ss<const ROUNDING: i32>(
    a: __m128, 
    b: __m128, 
    c: __m128
) -> __m128

🔬 This is a nightly-only experimental API. (stdsimd #48556)

This is supported on x86-64 and target feature avx512f only.

Multiply the lower single-precision (32-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 dst, and copy the upper 3 packed elements from a to the upper elements of dst.

Rounding is done according to the rounding[3:0] parameter, which can be one of:
(_MM_FROUND_TO_NEAREST_INT |_MM_FROUND_NO_EXC) // round to nearest, and suppress exceptions
(_MM_FROUND_TO_NEG_INF |_MM_FROUND_NO_EXC) // round down, and suppress exceptions
(_MM_FROUND_TO_POS_INF |_MM_FROUND_NO_EXC) // round up, and suppress exceptions
(_MM_FROUND_TO_ZERO |_MM_FROUND_NO_EXC) // truncate, and suppress exceptions
_MM_FROUND_CUR_DIRECTION // use MXCSR.RC; see _MM_SET_ROUNDING_MODE

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