# Function _mm_reduce_sh

Source

    pub fn _mm_reduce_sh(a: __m128h, b: __m128h, const IMM8: i32) -> __m128h

🔬This is a nightly-only experimental API. (`stdarch_x86_avx512_f16` #127213)
Available on (x86 or x86-64) and target feature `avx512fp16` and x86 only.
Expand description

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, 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:

- `_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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