__lasx_xvpcnt_b
LASX intrinsic · group: Bitwise Operations
Synopsis
__m256i __lasx_xvpcnt_b (__m256i a)
#include <lasxintrin.h>
Instruction: xvpcnt.b xr, xr
CPU Flags: LASX
Description
Count the number of ones (population, popcount) in 8-bit elements in a.
Examples
__m256i __lasx_xvpcnt_b(__m256i{ 0x1122334455667788, 0x99aabbccddeeff00, 0xabcdef1212341234, 0xaabbaabbddeeddee})
= 0x0202040204040602 0x0404060406060800 0x0505070202030203 0x0406040606060606
Operation
for (int i = 0; i < 32; i++) {
dst.byte[i] = popcount(a.byte[i]);
}
Tested on real machine.
Latency and Throughput
| CPU | µarch | Latency | Throughput (IPC) |
|---|---|---|---|
| 3C5000 | LA464 | 2 | 2 |
| 3A6000 | LA664 | 2 | 2 |
| 3C6000 | LA664 | 2 | 2 |