_mm_mask_popcnt_epi32
Classification
AVX-512, Bit Manipulation, CPUID Test: AVX512VPOPCNTDQ
Header File
Instruction
VPOPCNTD xmm {k}, xmm
Synopsis
_mm_mask_popcnt_epi32(__m128i src, __mmask8 k, __m128i a);
Description
Count the number of logical 1 bits in packed 32-bit integers in "a", and store the results in "dst" using writemask "k" (elements are copied from "src" when the corresponding mask bit is not set).
Operation
DEFINE POPCNT(a) {
count := 0
DO WHILE a > 0
count += a[0]
a >>= 1
OD
RETURN count
}
FOR j := 0 to 3
i := j*32
IF k[j]
dst[i+31:i] := POPCNT(a[i+31:i])
ELSE
dst[i+31:i] := src[i+31:i]
FI
ENDFOR
dst[MAX:128] := 0