BYOC backend Build Error

Development
#1

After implement my BYOC codegen, I call relay.build it returns me error like this

File "../src/target/stackvm/codegen_stackvm.cc", 
TVMError: unknown function call Op(tir.call_pure_extern)

Is there any reason and solution to this?

#2

First, you shouldn’t use stackvm. Use llvm for host codegen.

unknown function call Op(tir.call_pure_extern) means you have some backend-specific intrinsic functions our codegen doesn’t know about. You can dump the intrinsic name.

#3

I follow the instructions at here Bring Your Own Codegen To TVM — tvm 0.9.dev182+ge718f5a8a documentation to add the backend codegen for myop, this is code in my codegen.cc

runtime::Module MyopCompiler(const ObjectRef& ref) {
  MyopCodegen myop;
  return myop.CreateCSourceModule(ref);
}

TVM_REGISTER_GLOBAL("relay.ext.myop").set_body_typed(myopCompiler);

at the python side for building my network with only one layer (myop), here are my code

input1 = relay.var('data', shape=(),dtype='float32')
myop = relay.nn.myop(input1)
args = relay.analysis.free_vars(myop)
net = relay.Function(args, myop)

mod = tvm.IRModule.from_expr(net)
mod = relay.transform.InferType()(mod)

lib = relay.build(mod, target, params)

is there any step that I was missing? should I use relay.compile instead of relay.build?

when I print tvm.get_global_func("relay.ext.myop", True) it can return me something like

<tvm.runtime.packed_func.PackedFunc object at 0x7fabe521dc00>