Function _mm_mask_reduce_ps 

pub fn _mm_mask_reduce_ps(
    src: __m128,
    k: __mmask8,
    a: __m128,
    const IMM8: i32,
) -> __m128

Available on x86-64 and target feature avx512dq and target feature avx512vl only.

Extract the reduced argument of packed single-precision (32-bit) floating-point elements in a by the number of bits specified by imm8, and store the results in dst using writemask k (elements are copied from src to dst if the corresponding mask bit is not set). Rounding is done according to the imm8 parameter, which can be one of:

• _MM_FROUND_TO_NEAREST_INT : round to nearest
• _MM_FROUND_TO_NEG_INF : round down
• _MM_FROUND_TO_POS_INF : round up
• _MM_FROUND_TO_ZERO : truncate
• _MM_FROUND_CUR_DIRECTION : use MXCSR.RC - see _MM_SET_ROUNDING_MODE

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