Function _mm_mask_reduce_sh

#[target_feature(enable = "avx512fp16")]
pub fn _mm_mask_reduce_sh(src: __m128h, k: __mmask8, a: __m128h, b: __m128h, IMM8: i32) -> __m128h

Extract the reduced argument of the lower half-precision (16-bit) floating-point element in b by the number of bits specified by imm8, store the result in the lower element of dst using writemask k (the element is copied from src when mask bit 0 is not set), and copy the upper 7 packed elements from a to the upper elements of dst.

Rounding is done according to the imm8 parameter, which can be one of:

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