pub unsafe fn _mm_mask_roundscale_pd(
    src: __m128d,
    k: __mmask8,
    a: __m128d,
    const IMM8: i32
) -> __m128d
🔬 This is a nightly-only experimental API. (stdsimd #48556)
Available on x86 and target feature avx512f,avx512vl only.
Expand description

Round packed double-precision (64-bit) floating-point elements in a to the number of fraction bits specified by imm8, and store the results in dst using writemask k (elements are copied from src when the corresponding mask bit is not set).
Rounding is done according to the imm8[2:0] 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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