Builtin instruction(without parameter) not work

Clang Frontend
1

Hi,
I want add a intrinsic fun in my backend, But it not work.If I add para to this intrinsic func.It can work.What should I do?
I implement it as follow,

  1. Builtins*.def file,

BUILTIN(__builtin_dsp_idle, “”, “”)

  1. Intrinsincs*,def file,
def int_dsp_idle: GCCBuiltin<"__builtin_dsp_idle">,
  Intrinsic<[], [], [IntrNoMem, IntrNoReturn]>;

3)*Instrinfo.td

let isTerminator = 1 in {
def IDLE : F_Special_0Reg<4,0,0b11110000, (outs), (ins), "idle", [],NOP_Itin>;
}
def: Pat<(int_dsp_idle), (IDLE)>;

But clang can’t identify it.

error: use of unknown builtin ‘__builtin_dsp_idle’ [-Wimplicit-function-declaration]

2

BUILTIN(__builtin_dsp_idle, “v

def int_dsp_idle: GCCBuiltin<"__builtin_dsp_idle">,
  Intrinsic<[], [], []>;

Then it works.
Builtins.def give information about “BUILTIN”