__lsx_vsubwod_d_w

LSX intrinsic · group: Integer Computation

Synopsis

__m128i __lsx_vsubwod_d_w (__m128i a, __m128i b)
#include <lsxintrin.h>
Instruction: vsubwod.d.w vr, vr, vr
CPU Flags: LSX

Description

Subtract the odd-positioned signed 32-bit elements in b from the corresponding elements in a, extending both to 64-bit, and save the 64-bit result in dst.

Operation

for (int i = 0; i < 2; i++) {
  dst.dword[i] = (s64)(s32)a.word[2 * i + 1] - (s64)(s32)b.word[2 * i + 1];
}

// Expands to:

if (0) {
  dst.dword[0] = ((s64)((s32)a.word[1])) - ((s64)((s32)b.word[1]));
  dst.dword[1] = ((s64)((s32)a.word[3])) - ((s64)((s32)b.word[3]));
}

Tested on real machine.

Latency and Throughput

CPU µarch Latency Throughput (IPC)
3C5000 LA464 2 2
3A6000 LA664 2 2
3C6000 LA664 2 2
2K1000LA LA264 2 1
2K3000 LA364E 2 1

All intrinsics in alphabetical order