vnc: 0.948
risc-v: 0.937
device: 0.931
socket: 0.857
graphic: 0.827
network: 0.820
PID: 0.809
register: 0.729
files: 0.719
permissions: 0.668
VMM: 0.601
architecture: 0.599
ppc: 0.584
performance: 0.583
kernel: 0.583
TCG: 0.572
arm: 0.571
debug: 0.558
mistranslation: 0.532
virtual: 0.532
x86: 0.524
boot: 0.487
hypervisor: 0.486
semantic: 0.476
i386: 0.475
KVM: 0.423
peripherals: 0.378
user-level: 0.295
assembly: 0.275

RVV vfncvt.rtz.x.f.w Assertion failed
Description of problem:
when execute 
``` 
vsetvli        t0,       x0,         e16,      m1
vfncvt.rtz.x.f.w v0, v4
```
report error:

qemu-riscv64: ../target/riscv/translate.c:212: decode_save_opc: Assertion \`ctx->insn_start != NULL' failed. Segmentation fault (core dumped)
Steps to reproduce:
1. write the code
2. compile
3. excute
Additional information: