[BUG] Antares Max Recursion Depth Exceeded

[Niupple]

When trying to generate kernel by the IR of:

- einstein_v2(" output0[N, F, HO, WO] +=! input0[N, C, -0 + HO + KH, -0 + WO + KW] * input1[F, C, KH, KW] where HO in 1080, WO in 1920;  ", input_dict={ "input0" : { "dtype" : "float32", "shape" : [1, 48, 1080, 1920]} ,  "input1" : { "dtype" : "float32", "shape" : [16, 48, 1, 1]} }) ## @: plan/convfwd_nchw_v1

Antares terminated with the error info:

Traceback (most recent call last):
  File "./antares/antares_compiler.py", line 664, in <module>
    main_compute()
  File "./antares/antares_compiler.py", line 377, in main_compute
    task = autotvm.task.create("template_op", args=(), target=tvm_target)
  File "/opt/tvm/python/tvm/autotvm/task/task.py", line 457, in create
    sch, _ = ret.func(*args)
  File "/opt/tvm/python/tvm/autotvm/task/task.py", line 236, in __call__
    return self.fcustomized(*args, **kwargs)
  File "/antares/lang/generic.py", line 185, in get_template_op
    exec('import tvm; from tvm import topi; ' + program, globals())
  File "<string>", line 1, in <module>
  File "/antares/lang/generic.py", line 24, in einstein_v2
    ir = einstein_v2.emit_tvm_ir(exprss, input_dict, extra_outputs)
  File "/antares/lang/einstein_v2.py", line 473, in emit_tvm_ir
    return emit_tvm_ir_v2(exprss, input_dict, extra_outputs)
  File "/antares/lang/einstein_v2.py", line 389, in emit_tvm_ir_v2
    ast = parse_to_ast(s, inputs)
  File "/antares/lang/einstein_v2.py", line 262, in parse_to_ast
    _root = eval(rval)
  File "<string>", line 1, in <module>
  File "/antares/lang/einstein_v2.py", line 114, in __radd__
    return other.__radd__(self)
  File "/antares/lang/einstein_v2.py", line 114, in __radd__
    return other.__radd__(self)
  File "/antares/lang/einstein_v2.py", line 114, in __radd__
    return other.__radd__(self)
  [Previous line repeated 9979 more times]
  File "/antares/lang/einstein_v2.py", line 113, in __radd__
    other = OpTensor.parse(other)
RecursionError: maximum recursion depth exceeded

[ghostplant]

Thanks, it is fixed in PR(#109).