__lasx_xvssran_h_w
LASX intrinsic · group: Shift
Synopsis
__m256i __lasx_xvssran_h_w (__m256i a, __m256i b)
#include <lasxintrin.h>
Instruction: xvssran.h.w xr, xr, xr
CPU Flags: LASX
Description
Arithmetic right shift each signed 32-bit element in a by the corresponding element of b modulo 32, saturate the result to signed 16-bit, write it into the lower half of each 128-bit lane of dst, and zero the upper half.
Operation
for (int i = 0; i < 8; i++) {
if (i < 4) {
s32 temp = (s32)a.word[i] >> (b.word[i] & 31);
dst.half[i] = clamp<s32>(temp, -32768, 32767);
} else {
dst.half[i] = 0;
}
}
for (int i = 8; i < 16; i++) {
if (i < 12) {
s32 temp = (s32)a.word[i - 4] >> (b.word[i - 4] & 31);
dst.half[i] = clamp<s32>(temp, -32768, 32767);
} else {
dst.half[i] = 0;
}
}
Tested on real machine.
Latency and Throughput
| CPU | µarch | Latency | Throughput (IPC) |
|---|---|---|---|
| 3C5000 | LA464 | 4 | 1 |
| 3A6000 | LA664 | 4 | 2 |
| 3C6000 | LA664 | 4 | 2 |