Function `_mm256_dp_ps`

#[target_feature(enable = "avx")]
pub fn _mm256_dp_ps(a: __m256, b: __m256, IMM8: i32) -> __m256

Conditionally multiplies the packed single-precision (32-bit) floating-point elements in a and b using the high 4 bits in imm8, sum the four products, and conditionally return the sum using the low 4 bits of imm8.

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