armmov.d
LBT intrinsic · group: ARM Misc
Synopsis
Instruction: armmov.d rj
CPU Flags: LBT
Description
ARM-style move (with flag update): conditionally test the 64-bit value in rj and update ARMFLAGS (N, Z). Only ARMFLAGS (LBT4) is updated; the GPR is not modified.
Operation
if (arm_cond_holds(ARMFLAGS, cond)) {
uint64_t r = a;
ARMFLAGS.N = (r >> 63) & 1;
ARMFLAGS.Z = r == 0;
}
Tested on real machine.
Latency and Throughput
| CPU | µarch | Latency | Throughput (IPC) |
|---|---|---|---|
| 3C5000 | LA464 | 2 | 0.5(1/2) |
| 3C6000 | LA664 | 2 | 0.5(1/2) |