__lasx_xvpackod_d

LASX intrinsic · group: Misc

Synopsis

__m256i __lasx_xvpackod_d (__m256i a, __m256i b)
#include <lasxintrin.h>
Instruction: xvpackod.d xr, xr, xr
CPU Flags: LASX

Description

Interleave odd-positioned 64-bit elements of a and b: the element from b is placed at the even output position and the element from a at the following odd position.

Operation

for (int i = 0; i < 4; i++) {
  dst.dword[i] = (i % 2 == 1) ? a.dword[i] : b.dword[i + 1];
}

// Expands to:

if (0) {
  dst.dword[0] = b.dword[1];
  dst.dword[1] = a.dword[1];
  dst.dword[2] = b.dword[3];
  dst.dword[3] = a.dword[3];
}

Tested on real machine.

Latency and Throughput

CPU µarch Latency Throughput (IPC)
3C5000 LA464 1 2
3A6000 LA664 1 4
3C6000 LA664 1 4

All intrinsics in alphabetical order