Raise Unhandled CPU exception when i use uc->reg_write() to set segment: FS GS

[LakerMoon]

In runpe.py,Func: runpe
uc.reg_write(UC_X86_REG_FS, GDT_FS_IDX << 3)
uc.reg_write(UC_X86_REG_GS, GDT_GS_IDX << 3)

File "C:/Users/yue_hu/Downloads/x86-64-pe-emu-master/x86-64-pe-emu-master/runpe.py", line 483, in main
runpe(args.file, length)
File "C:/Users/yue_hu/Downloads/x86-64-pe-emu-master/x86-64-pe-emu-master/runpe.py", line 334, in runpe
uc.reg_write(UC_X86_REG_FS, GDT_FS_IDX << 3)
File "C:\Python27\lib\site-packages\unicorn\unicorn.py", line 448, in reg_write
raise UcError(status)
unicorn.unicorn.UcError: Unhandled CPU exception (UC_ERR_EXCEPTION)

Process finished with exit code 1

please how can i solve this issues