_mm256_maskz_cmul_pch
Classification
AVX-512, Arithmetic, CPUID Test: AVX512_FP16
Header File
Instruction
VFCMULCPH ymm {z}, ymm, ymm
Synopsis
_mm256_maskz_cmul_pch(__mmask8 k, __m256h a, __m256h b);
Description
Multiply packed complex numbers in "a" by the complex conjugates of packed complex numbers in "b", and store the results in "dst" using zeromask "k" (elements are zeroed out when the corresponding mask bit is not set). Each complex number is composed of two adjacent half-precision (16-bit) floating-point elements, which defines the complex number "complex = vec.fp16[0] + i * vec.fp16[1]", or the complex conjugate "conjugate = vec.fp16[0] - i * vec.fp16[1]".
Operation
FOR i := 0 to 7
IF k[i]
dst.fp16[2*i+0] := (a.fp16[2*i+0] * b.fp16[2*i+0]) + (a.fp16[2*i+1] * b.fp16[2*i+1])
dst.fp16[2*i+1] := (a.fp16[2*i+1] * b.fp16[2*i+0]) - (a.fp16[2*i+0] * b.fp16[2*i+1])
ELSE
dst.fp16[2*i+0] := 0
dst.fp16[2*i+1] := 0
FI
ENDFOR
dst[MAX:256] := 0