__lsx_vclz_d
LSX intrinsic · group: Bitwise Operations
Synopsis
__m128i __lsx_vclz_d (__m128i a)
#include <lsxintrin.h>
Instruction: vclz.d vr, vr
CPU Flags: LSX
Description
Count leading zeros of 64-bit elements in a.
Examples
__m128i __lsx_vclz_d(__m128i{0x1122334455667788, 0x99aabbccddeeff00})
= 0x0000000000000003 0x0000000000000000
Operation
for (int i = 0; i < 2; i++) {
dst.dword[i] = clz(a.dword[i]);
}
Tested on real machine.
Latency and Throughput
| CPU | µarch | Latency | Throughput (IPC) |
|---|---|---|---|
| 3C5000 | LA464 | 2 | 2 |
| 3A6000 | LA664 | 2 | 4 |
| 3C6000 | LA664 | 2 | 4 |
| 2K1000LA | LA264 | 2 | 1 |
| 2K3000 | LA364E | 1 | 1 |