pub unsafe fn _mm_mask_sub_round_ss<const ROUNDING: i32>(
    src: __m128,
    k: u8,
    a: __m128,
    b: __m128
) -> __m128
🔬 This is a nightly-only experimental API. (stdsimd)
This is supported on x86-64 and target feature avx512f only.
Expand description

Subtract the lower single-precision (32-bit) floating-point element in b from the lower single-precision (32-bit) floating-point element in a, 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 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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